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Java Source Code / Java Documentation » Net » lucene connector » org.apache.lucene.index 
Source Cross Reference  Class Diagram Java Document (Java Doc) 


java.lang.Object
   org.apache.lucene.index.IndexWriter

IndexWriter
public class IndexWriter (Code)
An IndexWriter creates and maintains an index.

The create argument to the constructor determines whether a new index is created, or whether an existing index is opened. Note that you can open an index with create=true even while readers are using the index. The old readers will continue to search the "point in time" snapshot they had opened, and won't see the newly created index until they re-open. There are also constructors with no create argument which will create a new index if there is not already an index at the provided path and otherwise open the existing index.

In either case, documents are added with addDocument and removed with deleteDocuments. A document can be updated with updateDocument (which just deletes and then adds the entire document). When finished adding, deleting and updating documents, close should be called.

These changes are buffered in memory and periodically flushed to the Directory (during the above method calls). A flush is triggered when there are enough buffered deletes (see IndexWriter.setMaxBufferedDeleteTerms ) or enough added documents since the last flush, whichever is sooner. For the added documents, flushing is triggered either by RAM usage of the documents (see IndexWriter.setRAMBufferSizeMB ) or the number of added documents. The default is to flush when RAM usage hits 16 MB. For best indexing speed you should flush by RAM usage with a large RAM buffer. You can also force a flush by calling IndexWriter.flush . When a flush occurs, both pending deletes and added documents are flushed to the index. A flush may also trigger one or more segment merges which by default run with a background thread so as not to block the addDocument calls (see below for changing the MergeScheduler ).

The optional autoCommit argument to the constructors controls visibility of the changes to IndexReader instances reading the same index. When this is false, changes are not visible until IndexWriter.close() is called. Note that changes will still be flushed to the org.apache.lucene.store.Directory as new files, but are not committed (no new segments_N file is written referencing the new files) until IndexWriter.close is called. If something goes terribly wrong (for example the JVM crashes) before IndexWriter.close() , then the index will reflect none of the changes made (it will remain in its starting state). You can also call IndexWriter.abort() , which closes the writer without committing any changes, and removes any index files that had been flushed but are now unreferenced. This mode is useful for preventing readers from refreshing at a bad time (for example after you've done all your deletes but before you've done your adds). It can also be used to implement simple single-writer transactional semantics ("all or none").

When autoCommit is true then every flush is also a commit ( IndexReader instances will see each flush as changes to the index). This is the default, to match the behavior before 2.2. When running in this mode, be careful not to refresh your readers while optimize or segment merges are taking place as this can tie up substantial disk space.

Regardless of autoCommit, an IndexReader or org.apache.lucene.search.IndexSearcher will only see the index as of the "point in time" that it was opened. Any changes committed to the index after the reader was opened are not visible until the reader is re-opened.

If an index will not have more documents added for a while and optimal search performance is desired, then the optimize method should be called before the index is closed.

Opening an IndexWriter creates a lock file for the directory in use. Trying to open another IndexWriter on the same directory will lead to a LockObtainFailedException . The LockObtainFailedException is also thrown if an IndexReader on the same directory is used to delete documents from the index.

Expert: IndexWriter allows an optional IndexDeletionPolicy implementation to be specified. You can use this to control when prior commits are deleted from the index. The default policy is KeepOnlyLastCommitDeletionPolicy which removes all prior commits as soon as a new commit is done (this matches behavior before 2.2). Creating your own policy can allow you to explicitly keep previous "point in time" commits alive in the index for some time, to allow readers to refresh to the new commit without having the old commit deleted out from under them. This is necessary on filesystems like NFS that do not support "delete on last close" semantics, which Lucene's "point in time" search normally relies on.

Expert: IndexWriter allows you to separately change the MergePolicy and the MergeScheduler . The MergePolicy is invoked whenever there are changes to the segments in the index. Its role is to select which merges to do, if any, and return a MergePolicy.MergeSpecification describing the merges. It also selects merges to do for optimize(). (The default is LogByteSizeMergePolicy . Then, the MergeScheduler is invoked with the requested merges and it decides when and how to run the merges. The default is ConcurrentMergeScheduler .



Field Summary
final public static  intDEFAULT_MAX_BUFFERED_DELETE_TERMS
     Disabled by default (because IndexWriter flushes by RAM usage by default).
final public static  intDEFAULT_MAX_BUFFERED_DOCS
     Disabled by default (because IndexWriter flushes by RAM usage by default).
final public static  intDEFAULT_MAX_FIELD_LENGTH
     Default value is 10,000.
final public static  intDEFAULT_MAX_MERGE_DOCS
    
final public static  intDEFAULT_MERGE_FACTOR
    
final public static  doubleDEFAULT_RAM_BUFFER_SIZE_MB
     Default value is 16 MB (which means flush when buffered docs consume 16 MB RAM).
final public static  intDEFAULT_TERM_INDEX_INTERVAL
     Default value is 128.
final public static  intDISABLE_AUTO_FLUSH
    
final public static  intMAX_TERM_LENGTH
     Absolute hard maximum length for a term.
final public static  StringWRITE_LOCK_NAME
     Name of the write lock in the index.
public static  longWRITE_LOCK_TIMEOUT
     Default value for the write lock timeout (1,000).

Constructor Summary
public  IndexWriter(String path, Analyzer a, boolean create)
     Constructs an IndexWriter for the index in path. Text will be analyzed with a.
public  IndexWriter(File path, Analyzer a, boolean create)
     Constructs an IndexWriter for the index in path. Text will be analyzed with a.
public  IndexWriter(Directory d, Analyzer a, boolean create)
     Constructs an IndexWriter for the index in d. Text will be analyzed with a.
public  IndexWriter(String path, Analyzer a)
     Constructs an IndexWriter for the index in path, first creating it if it does not already exist.
public  IndexWriter(File path, Analyzer a)
     Constructs an IndexWriter for the index in path, first creating it if it does not already exist.
public  IndexWriter(Directory d, Analyzer a)
     Constructs an IndexWriter for the index in d, first creating it if it does not already exist.
public  IndexWriter(Directory d, boolean autoCommit, Analyzer a)
     Constructs an IndexWriter for the index in d, first creating it if it does not already exist.
public  IndexWriter(Directory d, boolean autoCommit, Analyzer a, boolean create)
     Constructs an IndexWriter for the index in d. Text will be analyzed with a.
public  IndexWriter(Directory d, boolean autoCommit, Analyzer a, IndexDeletionPolicy deletionPolicy)
     Expert: constructs an IndexWriter with a custom IndexDeletionPolicy , for the index in d, first creating it if it does not already exist.
public  IndexWriter(Directory d, boolean autoCommit, Analyzer a, boolean create, IndexDeletionPolicy deletionPolicy)
     Expert: constructs an IndexWriter with a custom IndexDeletionPolicy , for the index in d. Text will be analyzed with a.

Method Summary
public  voidabort()
     Close the IndexWriter without committing any of the changes that have occurred since it was opened.
public  voidaddDocument(Document doc)
     Adds a document to this index.
public  voidaddDocument(Document doc, Analyzer analyzer)
     Adds a document to this index, using the provided analyzer instead of the value of IndexWriter.getAnalyzer() .
public synchronized  voidaddIndexes(Directory[] dirs)
     Merges all segments from an array of indexes into this index.

This may be used to parallelize batch indexing.

public synchronized  voidaddIndexes(IndexReader[] readers)
     Merges the provided indexes into this index.

After this completes, the index is optimized.

public synchronized  voidaddIndexesNoOptimize(Directory[] dirs)
     Merges all segments from an array of indexes into this index.

This is similar to addIndexes(Directory[]).

synchronized  voidaddMergeException(MergePolicy.OneMerge merge)
    
public  voidclose()
     Flushes all changes to an index and closes all associated files.

If an Exception is hit during close, eg due to disk full or some other reason, then both the on-disk index and the internal state of the IndexWriter instance will be consistent.

public  voidclose(boolean waitForMerges)
     Closes the index with or without waiting for currently running merges to finish.
public  voiddeleteDocuments(Term term)
     Deletes the document(s) containing term.
public  voiddeleteDocuments(Term[] terms)
     Deletes the document(s) containing any of the terms.
 voiddoAfterFlush()
    
public synchronized  intdocCount()
     Returns the number of documents currently in this index.
final protected  voidensureOpen()
     Used internally to throw an AlreadyClosedException if this IndexWriter has been closed.
protected  voidfinalize()
     Release the write lock, if needed.
final public  voidflush()
     Flush all in-memory buffered updates (adds and deletes) to the Directory.
final protected  voidflush(boolean triggerMerge, boolean flushDocStores)
     Flush all in-memory buffered udpates (adds and deletes) to the Directory.
public  AnalyzergetAnalyzer()
     Returns the analyzer used by this index.
final synchronized  intgetBufferedDeleteTermsSize()
    
public static  PrintStreamgetDefaultInfoStream()
     Returns the current default infoStream for newly instantiated IndexWriters.
public static  longgetDefaultWriteLockTimeout()
     Returns default write lock timeout for newly instantiated IndexWriters.
public  DirectorygetDirectory()
     Returns the Directory used by this index.
final synchronized  intgetDocCount(int i)
    
public  PrintStreamgetInfoStream()
     Returns the current infoStream in use by this writer.
public  intgetMaxBufferedDeleteTerms()
     Returns the number of buffered deleted terms that will trigger a flush if enabled.
public  intgetMaxBufferedDocs()
     Returns the number of buffered added documents that will trigger a flush if enabled.
public  intgetMaxFieldLength()
     Returns the maximum number of terms that will be indexed for a single field in a document.
public  intgetMaxMergeDocs()
    

Returns the largest segment (measured by document count) that may be merged with other segments.

Note that this method is a convenience method: it just calls mergePolicy.getMaxMergeDocs as long as mergePolicy is an instance of LogMergePolicy .

public  intgetMergeFactor()
    

Returns the number of segments that are merged at once and also controls the total number of segments allowed to accumulate in the index.

Note that this method is a convenience method: it just calls mergePolicy.getMergeFactor as long as mergePolicy is an instance of LogMergePolicy .

public  MergePolicygetMergePolicy()
     Expert: returns the current MergePolicy in use by this writer.
public  MergeSchedulergetMergeScheduler()
     Expert: returns the current MergePolicy in use by this writer.
synchronized  MergePolicy.OneMergegetNextMerge()
    
final synchronized  intgetNumBufferedDeleteTerms()
    
final synchronized  intgetNumBufferedDocuments()
    
public  doublegetRAMBufferSizeMB()
     Returns the value set by IndexWriter.setRAMBufferSizeMB if enabled.
final synchronized  intgetSegmentCount()
    
public  SimilaritygetSimilarity()
     Expert: Return the Similarity implementation used by this IndexWriter.
public  intgetTermIndexInterval()
     Expert: Return the interval between indexed terms.
public  booleangetUseCompoundFile()
    

Get the current setting of whether newly flushed segments will use the compound file format.

public  longgetWriteLockTimeout()
     Returns allowed timeout when acquiring the write lock.
final public  voidmaybeMerge()
     Expert: asks the mergePolicy whether any merges are necessary now and if so, runs the requested merges and then iterate (test again if merges are needed) until no more merges are returned by the mergePolicy. Explicit calls to maybeMerge() are usually not necessary.
final  voidmerge(MergePolicy.OneMerge merge)
     Merges the indicated segments, replacing them in the stack with a single segment.
final synchronized  voidmergeFinish(MergePolicy.OneMerge merge)
     Does fininishing for a merge, which is fast but holds the synchronized lock on IndexWriter instance.
final synchronized  voidmergeInit(MergePolicy.OneMerge merge)
     Does initial setup for a merge, which is fast but holds the synchronized lock on IndexWriter instance.
public  voidmessage(String message)
     Prints a message to the infoStream (if non-null), prefixed with the identifying information for this writer and the thread that's calling it.
final  StringnewSegmentName()
    
 SegmentInfonewestSegment()
    
final public synchronized  intnumRamDocs()
     Expert: Return the number of documents whose segments are currently cached in memory.
public  voidoptimize()
     Requests an "optimize" operation on an index, priming the index for the fastest available search.
public  voidoptimize(int maxNumSegments)
     Optimize the index down to <= maxNumSegments.
public  voidoptimize(boolean doWait)
     Just like IndexWriter.optimize() , except you can specify whether the call should block until the optimize completes.
public  voidoptimize(int maxNumSegments, boolean doWait)
     Just like IndexWriter.optimize(int) , except you can specify whether the call should block until the optimize completes.
final public  longramSizeInBytes()
     Expert: Return the total size of all index files currently cached in memory.
final synchronized  booleanregisterMerge(MergePolicy.OneMerge merge)
     Checks whether this merge involves any segments already participating in a merge.
public synchronized  StringsegString()
    
public static  voidsetDefaultInfoStream(PrintStream infoStream)
     If non-null, this will be the default infoStream used by a newly instantiated IndexWriter.
public static  voidsetDefaultWriteLockTimeout(long writeLockTimeout)
     Sets the default (for any instance of IndexWriter) maximum time to wait for a write lock (in milliseconds).
public  voidsetInfoStream(PrintStream infoStream)
     If non-null, information about merges, deletes and a message when maxFieldLength is reached will be printed to this.
public  voidsetMaxBufferedDeleteTerms(int maxBufferedDeleteTerms)
    

Determines the minimal number of delete terms required before the buffered in-memory delete terms are applied and flushed.

public  voidsetMaxBufferedDocs(int maxBufferedDocs)
     Determines the minimal number of documents required before the buffered in-memory documents are flushed as a new Segment.
public  voidsetMaxFieldLength(int maxFieldLength)
     The maximum number of terms that will be indexed for a single field in a document.
public  voidsetMaxMergeDocs(int maxMergeDocs)
    

Determines the largest segment (measured by document count) that may be merged with other segments. Small values (e.g., less than 10,000) are best for interactive indexing, as this limits the length of pauses while indexing to a few seconds.

public  voidsetMergeFactor(int mergeFactor)
     Determines how often segment indices are merged by addDocument().
public  voidsetMergePolicy(MergePolicy mp)
     Expert: set the merge policy used by this writer.
public  voidsetMergeScheduler(MergeScheduler mergeScheduler)
     Expert: set the merge scheduler used by this writer.
public  voidsetRAMBufferSizeMB(double mb)
     Determines the amount of RAM that may be used for buffering added documents before they are flushed as a new Segment.
public  voidsetSimilarity(Similarity similarity)
     Expert: Set the Similarity implementation used by this IndexWriter.
public  voidsetTermIndexInterval(int interval)
     Expert: Set the interval between indexed terms.
public  voidsetUseCompoundFile(boolean value)
    

Setting to turn on usage of a compound file.

public  voidsetWriteLockTimeout(long writeLockTimeout)
     Sets the maximum time to wait for a write lock (in milliseconds) for this instance of IndexWriter.
public  voidupdateDocument(Term term, Document doc)
     Updates a document by first deleting the document(s) containing term and then adding the new document.
public  voidupdateDocument(Term term, Document doc, Analyzer analyzer)
     Updates a document by first deleting the document(s) containing term and then adding the new document.

Field Detail
DEFAULT_MAX_BUFFERED_DELETE_TERMS
final public static int DEFAULT_MAX_BUFFERED_DELETE_TERMS(Code)
Disabled by default (because IndexWriter flushes by RAM usage by default). Change using IndexWriter.setMaxBufferedDeleteTerms(int) .



DEFAULT_MAX_BUFFERED_DOCS
final public static int DEFAULT_MAX_BUFFERED_DOCS(Code)
Disabled by default (because IndexWriter flushes by RAM usage by default). Change using IndexWriter.setMaxBufferedDocs(int) .



DEFAULT_MAX_FIELD_LENGTH
final public static int DEFAULT_MAX_FIELD_LENGTH(Code)
Default value is 10,000. Change using IndexWriter.setMaxFieldLength(int) .



DEFAULT_MAX_MERGE_DOCS
final public static int DEFAULT_MAX_MERGE_DOCS(Code)

See Also:   LogDocMergePolicy.DEFAULT_MAX_MERGE_DOCS



DEFAULT_MERGE_FACTOR
final public static int DEFAULT_MERGE_FACTOR(Code)

See Also:   LogMergePolicy.DEFAULT_MERGE_FACTOR



DEFAULT_RAM_BUFFER_SIZE_MB
final public static double DEFAULT_RAM_BUFFER_SIZE_MB(Code)
Default value is 16 MB (which means flush when buffered docs consume 16 MB RAM). Change using IndexWriter.setRAMBufferSizeMB .



DEFAULT_TERM_INDEX_INTERVAL
final public static int DEFAULT_TERM_INDEX_INTERVAL(Code)
Default value is 128. Change using IndexWriter.setTermIndexInterval(int) .



DISABLE_AUTO_FLUSH
final public static int DISABLE_AUTO_FLUSH(Code)
Value to denote a flush trigger is disabled



MAX_TERM_LENGTH
final public static int MAX_TERM_LENGTH(Code)
Absolute hard maximum length for a term. If a term arrives from the analyzer longer than this length, it is skipped and a message is printed to infoStream, if set (see IndexWriter.setInfoStream ).



WRITE_LOCK_NAME
final public static String WRITE_LOCK_NAME(Code)
Name of the write lock in the index.



WRITE_LOCK_TIMEOUT
public static long WRITE_LOCK_TIMEOUT(Code)
Default value for the write lock timeout (1,000).
See Also:   IndexWriter.setDefaultWriteLockTimeout




Constructor Detail
IndexWriter
public IndexWriter(String path, Analyzer a, boolean create) throws CorruptIndexException, LockObtainFailedException, IOException(Code)
Constructs an IndexWriter for the index in path. Text will be analyzed with a. If create is true, then a new, empty index will be created in path, replacing the index already there, if any.
Parameters:
  path - the path to the index directory
Parameters:
  a - the analyzer to use
Parameters:
  create - true to create the index or overwritethe existing one; false to append to the existingindex
throws:
  CorruptIndexException - if the index is corrupt
throws:
  LockObtainFailedException - if another writerhas this index open (write.lock could notbe obtained)
throws:
  IOException - if the directory cannot be read/written to, orif it does not exist and create isfalse or if there is any other low-levelIO error



IndexWriter
public IndexWriter(File path, Analyzer a, boolean create) throws CorruptIndexException, LockObtainFailedException, IOException(Code)
Constructs an IndexWriter for the index in path. Text will be analyzed with a. If create is true, then a new, empty index will be created in path, replacing the index already there, if any.
Parameters:
  path - the path to the index directory
Parameters:
  a - the analyzer to use
Parameters:
  create - true to create the index or overwritethe existing one; false to append to the existingindex
throws:
  CorruptIndexException - if the index is corrupt
throws:
  LockObtainFailedException - if another writerhas this index open (write.lock could notbe obtained)
throws:
  IOException - if the directory cannot be read/written to, orif it does not exist and create isfalse or if there is any other low-levelIO error



IndexWriter
public IndexWriter(Directory d, Analyzer a, boolean create) throws CorruptIndexException, LockObtainFailedException, IOException(Code)
Constructs an IndexWriter for the index in d. Text will be analyzed with a. If create is true, then a new, empty index will be created in d, replacing the index already there, if any.
Parameters:
  d - the index directory
Parameters:
  a - the analyzer to use
Parameters:
  create - true to create the index or overwritethe existing one; false to append to the existingindex
throws:
  CorruptIndexException - if the index is corrupt
throws:
  LockObtainFailedException - if another writerhas this index open (write.lock could notbe obtained)
throws:
  IOException - if the directory cannot be read/written to, orif it does not exist and create isfalse or if there is any other low-levelIO error



IndexWriter
public IndexWriter(String path, Analyzer a) throws CorruptIndexException, LockObtainFailedException, IOException(Code)
Constructs an IndexWriter for the index in path, first creating it if it does not already exist. Text will be analyzed with a.
Parameters:
  path - the path to the index directory
Parameters:
  a - the analyzer to use
throws:
  CorruptIndexException - if the index is corrupt
throws:
  LockObtainFailedException - if another writerhas this index open (write.lock could notbe obtained)
throws:
  IOException - if the directory cannot beread/written to or if there is any other low-levelIO error



IndexWriter
public IndexWriter(File path, Analyzer a) throws CorruptIndexException, LockObtainFailedException, IOException(Code)
Constructs an IndexWriter for the index in path, first creating it if it does not already exist. Text will be analyzed with a.
Parameters:
  path - the path to the index directory
Parameters:
  a - the analyzer to use
throws:
  CorruptIndexException - if the index is corrupt
throws:
  LockObtainFailedException - if another writerhas this index open (write.lock could notbe obtained)
throws:
  IOException - if the directory cannot beread/written to or if there is any other low-levelIO error



IndexWriter
public IndexWriter(Directory d, Analyzer a) throws CorruptIndexException, LockObtainFailedException, IOException(Code)
Constructs an IndexWriter for the index in d, first creating it if it does not already exist. Text will be analyzed with a.
Parameters:
  d - the index directory
Parameters:
  a - the analyzer to use
throws:
  CorruptIndexException - if the index is corrupt
throws:
  LockObtainFailedException - if another writerhas this index open (write.lock could notbe obtained)
throws:
  IOException - if the directory cannot beread/written to or if there is any other low-levelIO error



IndexWriter
public IndexWriter(Directory d, boolean autoCommit, Analyzer a) throws CorruptIndexException, LockObtainFailedException, IOException(Code)
Constructs an IndexWriter for the index in d, first creating it if it does not already exist. Text will be analyzed with a.
Parameters:
  d - the index directory
Parameters:
  autoCommit - see above
Parameters:
  a - the analyzer to use
throws:
  CorruptIndexException - if the index is corrupt
throws:
  LockObtainFailedException - if another writerhas this index open (write.lock could notbe obtained)
throws:
  IOException - if the directory cannot beread/written to or if there is any other low-levelIO error



IndexWriter
public IndexWriter(Directory d, boolean autoCommit, Analyzer a, boolean create) throws CorruptIndexException, LockObtainFailedException, IOException(Code)
Constructs an IndexWriter for the index in d. Text will be analyzed with a. If create is true, then a new, empty index will be created in d, replacing the index already there, if any.
Parameters:
  d - the index directory
Parameters:
  autoCommit - see above
Parameters:
  a - the analyzer to use
Parameters:
  create - true to create the index or overwritethe existing one; false to append to the existingindex
throws:
  CorruptIndexException - if the index is corrupt
throws:
  LockObtainFailedException - if another writerhas this index open (write.lock could notbe obtained)
throws:
  IOException - if the directory cannot be read/written to, orif it does not exist and create isfalse or if there is any other low-levelIO error



IndexWriter
public IndexWriter(Directory d, boolean autoCommit, Analyzer a, IndexDeletionPolicy deletionPolicy) throws CorruptIndexException, LockObtainFailedException, IOException(Code)
Expert: constructs an IndexWriter with a custom IndexDeletionPolicy , for the index in d, first creating it if it does not already exist. Text will be analyzed with a.
Parameters:
  d - the index directory
Parameters:
  autoCommit - see above
Parameters:
  a - the analyzer to use
Parameters:
  deletionPolicy - see above
throws:
  CorruptIndexException - if the index is corrupt
throws:
  LockObtainFailedException - if another writerhas this index open (write.lock could notbe obtained)
throws:
  IOException - if the directory cannot beread/written to or if there is any other low-levelIO error



IndexWriter
public IndexWriter(Directory d, boolean autoCommit, Analyzer a, boolean create, IndexDeletionPolicy deletionPolicy) throws CorruptIndexException, LockObtainFailedException, IOException(Code)
Expert: constructs an IndexWriter with a custom IndexDeletionPolicy , for the index in d. Text will be analyzed with a. If create is true, then a new, empty index will be created in d, replacing the index already there, if any.
Parameters:
  d - the index directory
Parameters:
  autoCommit - see above
Parameters:
  a - the analyzer to use
Parameters:
  create - true to create the index or overwritethe existing one; false to append to the existingindex
Parameters:
  deletionPolicy - see above
throws:
  CorruptIndexException - if the index is corrupt
throws:
  LockObtainFailedException - if another writerhas this index open (write.lock could notbe obtained)
throws:
  IOException - if the directory cannot be read/written to, orif it does not exist and create isfalse or if there is any other low-levelIO error




Method Detail
abort
public void abort() throws IOException(Code)
Close the IndexWriter without committing any of the changes that have occurred since it was opened. This removes any temporary files that had been created, after which the state of the index will be the same as it was when this writer was first opened. This can only be called when this IndexWriter was opened with autoCommit=false.
throws:
  IllegalStateException - if this is called whenthe writer was opened with autoCommit=true.
throws:
  IOException - if there is a low-level IO error



addDocument
public void addDocument(Document doc) throws CorruptIndexException, IOException(Code)
Adds a document to this index. If the document contains more than IndexWriter.setMaxFieldLength(int) terms for a given field, the remainder are discarded.

Note that if an Exception is hit (for example disk full) then the index will be consistent, but this document may not have been added. Furthermore, it's possible the index will have one segment in non-compound format even when using compound files (when a merge has partially succeeded).

This method periodically flushes pending documents to the Directory (every IndexWriter.setMaxBufferedDocs ), and also periodically merges segments in the index (every IndexWriter.setMergeFactor flushes). When this occurs, the method will take more time to run (possibly a long time if the index is large), and will require free temporary space in the Directory to do the merging.

The amount of free space required when a merge is triggered is up to 1X the size of all segments being merged, when no readers/searchers are open against the index, and up to 2X the size of all segments being merged when readers/searchers are open against the index (see IndexWriter.optimize() for details). The sequence of primitive merge operations performed is governed by the merge policy.

Note that each term in the document can be no longer than 16383 characters, otherwise an IllegalArgumentException will be thrown.


throws:
  CorruptIndexException - if the index is corrupt
throws:
  IOException - if there is a low-level IO error



addDocument
public void addDocument(Document doc, Analyzer analyzer) throws CorruptIndexException, IOException(Code)
Adds a document to this index, using the provided analyzer instead of the value of IndexWriter.getAnalyzer() . If the document contains more than IndexWriter.setMaxFieldLength(int) terms for a given field, the remainder are discarded.

See IndexWriter.addDocument(Document) for details on index and IndexWriter state after an Exception, and flushing/merging temporary free space requirements.


throws:
  CorruptIndexException - if the index is corrupt
throws:
  IOException - if there is a low-level IO error



addIndexes
public synchronized void addIndexes(Directory[] dirs) throws CorruptIndexException, IOException(Code)
Merges all segments from an array of indexes into this index.

This may be used to parallelize batch indexing. A large document collection can be broken into sub-collections. Each sub-collection can be indexed in parallel, on a different thread, process or machine. The complete index can then be created by merging sub-collection indexes with this method.

NOTE: the index in each Directory must not be changed (opened by a writer) while this method is running. This method does not acquire a write lock in each input Directory, so it is up to the caller to enforce this.

After this completes, the index is optimized.

This method is transactional in how Exceptions are handled: it does not commit a new segments_N file until all indexes are added. This means if an Exception occurs (for example disk full), then either no indexes will have been added or they all will have been.

If an Exception is hit, it's still possible that all indexes were successfully added. This happens when the Exception is hit when trying to build a CFS file. In this case, one segment in the index will be in non-CFS format, even when using compound file format.

Also note that on an Exception, the index may still have been partially or fully optimized even though none of the input indexes were added.

Note that this requires temporary free space in the Directory up to 2X the sum of all input indexes (including the starting index). If readers/searchers are open against the starting index, then temporary free space required will be higher by the size of the starting index (see IndexWriter.optimize() for details).

Once this completes, the final size of the index will be less than the sum of all input index sizes (including the starting index). It could be quite a bit smaller (if there were many pending deletes) or just slightly smaller.

See LUCENE-702 for details.


throws:
  CorruptIndexException - if the index is corrupt
throws:
  IOException - if there is a low-level IO error



addIndexes
public synchronized void addIndexes(IndexReader[] readers) throws CorruptIndexException, IOException(Code)
Merges the provided indexes into this index.

After this completes, the index is optimized.

The provided IndexReaders are not closed.

See IndexWriter.addIndexes(Directory[]) for details on transactional semantics, temporary free space required in the Directory, and non-CFS segments on an Exception.


throws:
  CorruptIndexException - if the index is corrupt
throws:
  IOException - if there is a low-level IO error



addIndexesNoOptimize
public synchronized void addIndexesNoOptimize(Directory[] dirs) throws CorruptIndexException, IOException(Code)
Merges all segments from an array of indexes into this index.

This is similar to addIndexes(Directory[]). However, no optimize() is called either at the beginning or at the end. Instead, merges are carried out as necessary.

NOTE: the index in each Directory must not be changed (opened by a writer) while this method is running. This method does not acquire a write lock in each input Directory, so it is up to the caller to enforce this.

This requires this index not be among those to be added, and the upper bound* of those segment doc counts not exceed maxMergeDocs.

See IndexWriter.addIndexes(Directory[]) for details on transactional semantics, temporary free space required in the Directory, and non-CFS segments on an Exception.


throws:
  CorruptIndexException - if the index is corrupt
throws:
  IOException - if there is a low-level IO error



addMergeException
synchronized void addMergeException(MergePolicy.OneMerge merge)(Code)



close
public void close() throws CorruptIndexException, IOException(Code)
Flushes all changes to an index and closes all associated files.

If an Exception is hit during close, eg due to disk full or some other reason, then both the on-disk index and the internal state of the IndexWriter instance will be consistent. However, the close will not be complete even though part of it (flushing buffered documents) may have succeeded, so the write lock will still be held.

If you can correct the underlying cause (eg free up some disk space) then you can call close() again. Failing that, if you want to force the write lock to be released (dangerous, because you may then lose buffered docs in the IndexWriter instance) then you can do something like this:

 try {
 writer.close();
 } finally {
 if (IndexReader.isLocked(directory)) {
 IndexReader.unlock(directory);
 }
 }
 
after which, you must be certain not to use the writer instance anymore.


throws:
  CorruptIndexException - if the index is corrupt
throws:
  IOException - if there is a low-level IO error



close
public void close(boolean waitForMerges) throws CorruptIndexException, IOException(Code)
Closes the index with or without waiting for currently running merges to finish. This is only meaningful when using a MergeScheduler that runs merges in background threads.
Parameters:
  waitForMerges - if true, this call will blockuntil all merges complete; else, it will ask allrunning merges to abort, wait until those merges havefinished (which should be at most a few seconds), andthen return.



deleteDocuments
public void deleteDocuments(Term term) throws CorruptIndexException, IOException(Code)
Deletes the document(s) containing term.
Parameters:
  term - the term to identify the documents to be deleted
throws:
  CorruptIndexException - if the index is corrupt
throws:
  IOException - if there is a low-level IO error



deleteDocuments
public void deleteDocuments(Term[] terms) throws CorruptIndexException, IOException(Code)
Deletes the document(s) containing any of the terms. All deletes are flushed at the same time.
Parameters:
  terms - array of terms to identify the documentsto be deleted
throws:
  CorruptIndexException - if the index is corrupt
throws:
  IOException - if there is a low-level IO error



doAfterFlush
void doAfterFlush() throws IOException(Code)



docCount
public synchronized int docCount()(Code)
Returns the number of documents currently in this index.



ensureOpen
final protected void ensureOpen() throws AlreadyClosedException(Code)
Used internally to throw an AlreadyClosedException if this IndexWriter has been closed.
throws:
  AlreadyClosedException - if this IndexWriter is



finalize
protected void finalize() throws Throwable(Code)
Release the write lock, if needed.



flush
final public void flush() throws CorruptIndexException, IOException(Code)
Flush all in-memory buffered updates (adds and deletes) to the Directory.

Note: if autoCommit=false, flushed data would still not be visible to readers, until IndexWriter.close is called.
throws:
  CorruptIndexException - if the index is corrupt
throws:
  IOException - if there is a low-level IO error




flush
final protected void flush(boolean triggerMerge, boolean flushDocStores) throws CorruptIndexException, IOException(Code)
Flush all in-memory buffered udpates (adds and deletes) to the Directory.
Parameters:
  triggerMerge - if true, we may merge segments (ifdeletes or docs were flushed) if necessary
Parameters:
  flushDocStores - if false we are allowed to keepdoc stores open to share with the next segment



getAnalyzer
public Analyzer getAnalyzer()(Code)
Returns the analyzer used by this index.



getBufferedDeleteTermsSize
final synchronized int getBufferedDeleteTermsSize()(Code)



getDefaultInfoStream
public static PrintStream getDefaultInfoStream()(Code)
Returns the current default infoStream for newly instantiated IndexWriters.
See Also:   IndexWriter.setDefaultInfoStream



getDefaultWriteLockTimeout
public static long getDefaultWriteLockTimeout()(Code)
Returns default write lock timeout for newly instantiated IndexWriters.
See Also:   IndexWriter.setDefaultWriteLockTimeout



getDirectory
public Directory getDirectory()(Code)
Returns the Directory used by this index.



getDocCount
final synchronized int getDocCount(int i)(Code)



getInfoStream
public PrintStream getInfoStream()(Code)
Returns the current infoStream in use by this writer.
See Also:   IndexWriter.setInfoStream



getMaxBufferedDeleteTerms
public int getMaxBufferedDeleteTerms()(Code)
Returns the number of buffered deleted terms that will trigger a flush if enabled.
See Also:   IndexWriter.setMaxBufferedDeleteTerms



getMaxBufferedDocs
public int getMaxBufferedDocs()(Code)
Returns the number of buffered added documents that will trigger a flush if enabled.
See Also:   IndexWriter.setMaxBufferedDocs



getMaxFieldLength
public int getMaxFieldLength()(Code)
Returns the maximum number of terms that will be indexed for a single field in a document.
See Also:   IndexWriter.setMaxFieldLength



getMaxMergeDocs
public int getMaxMergeDocs()(Code)

Returns the largest segment (measured by document count) that may be merged with other segments.

Note that this method is a convenience method: it just calls mergePolicy.getMaxMergeDocs as long as mergePolicy is an instance of LogMergePolicy . Otherwise an IllegalArgumentException is thrown.


See Also:   IndexWriter.setMaxMergeDocs



getMergeFactor
public int getMergeFactor()(Code)

Returns the number of segments that are merged at once and also controls the total number of segments allowed to accumulate in the index.

Note that this method is a convenience method: it just calls mergePolicy.getMergeFactor as long as mergePolicy is an instance of LogMergePolicy . Otherwise an IllegalArgumentException is thrown.


See Also:   IndexWriter.setMergeFactor



getMergePolicy
public MergePolicy getMergePolicy()(Code)
Expert: returns the current MergePolicy in use by this writer.
See Also:   IndexWriter.setMergePolicy



getMergeScheduler
public MergeScheduler getMergeScheduler()(Code)
Expert: returns the current MergePolicy in use by this writer.
See Also:   IndexWriter.setMergePolicy



getNextMerge
synchronized MergePolicy.OneMerge getNextMerge()(Code)
Expert: the MergeScheduler calls this method to retrieve the next merge requested by the MergePolicy



getNumBufferedDeleteTerms
final synchronized int getNumBufferedDeleteTerms()(Code)



getNumBufferedDocuments
final synchronized int getNumBufferedDocuments()(Code)



getRAMBufferSizeMB
public double getRAMBufferSizeMB()(Code)
Returns the value set by IndexWriter.setRAMBufferSizeMB if enabled.



getSegmentCount
final synchronized int getSegmentCount()(Code)



getSimilarity
public Similarity getSimilarity()(Code)
Expert: Return the Similarity implementation used by this IndexWriter.

This defaults to the current value of Similarity.getDefault .




getTermIndexInterval
public int getTermIndexInterval()(Code)
Expert: Return the interval between indexed terms.
See Also:   IndexWriter.setTermIndexInterval(int)



getUseCompoundFile
public boolean getUseCompoundFile()(Code)

Get the current setting of whether newly flushed segments will use the compound file format. Note that this just returns the value previously set with setUseCompoundFile(boolean), or the default value (true). You cannot use this to query the status of previously flushed segments.

Note that this method is a convenience method: it just calls mergePolicy.getUseCompoundFile as long as mergePolicy is an instance of LogMergePolicy . Otherwise an IllegalArgumentException is thrown.


See Also:   IndexWriter.setUseCompoundFile(boolean)



getWriteLockTimeout
public long getWriteLockTimeout()(Code)
Returns allowed timeout when acquiring the write lock.
See Also:   IndexWriter.setWriteLockTimeout



maybeMerge
final public void maybeMerge() throws CorruptIndexException, IOException(Code)
Expert: asks the mergePolicy whether any merges are necessary now and if so, runs the requested merges and then iterate (test again if merges are needed) until no more merges are returned by the mergePolicy. Explicit calls to maybeMerge() are usually not necessary. The most common case is when merge policy parameters have changed.



merge
final void merge(MergePolicy.OneMerge merge) throws CorruptIndexException, IOException(Code)
Merges the indicated segments, replacing them in the stack with a single segment.



mergeFinish
final synchronized void mergeFinish(MergePolicy.OneMerge merge) throws IOException(Code)
Does fininishing for a merge, which is fast but holds the synchronized lock on IndexWriter instance.



mergeInit
final synchronized void mergeInit(MergePolicy.OneMerge merge) throws IOException(Code)
Does initial setup for a merge, which is fast but holds the synchronized lock on IndexWriter instance.



message
public void message(String message)(Code)
Prints a message to the infoStream (if non-null), prefixed with the identifying information for this writer and the thread that's calling it.



newSegmentName
final String newSegmentName()(Code)



newestSegment
SegmentInfo newestSegment()(Code)



numRamDocs
final public synchronized int numRamDocs()(Code)
Expert: Return the number of documents whose segments are currently cached in memory. Useful when calling flush()



optimize
public void optimize() throws CorruptIndexException, IOException(Code)
Requests an "optimize" operation on an index, priming the index for the fastest available search. Traditionally this has meant merging all segments into a single segment as is done in the default merge policy, but individaul merge policies may implement optimize in different ways.
See Also:   LogMergePolicy.findMergesForOptimize
See Also:   

It is recommended that this method be called upon completion of indexing. In
See Also:   environments with frequent updates, optimize is best done during low volume times, if at all.
See Also:   


See Also:   

See http://www.gossamer-threads.com/lists/lucene/java-dev/47895 for more discussion.


See Also:   

Note that this can require substantial temporary free
See Also:   space in the Directory (see See Also:   href="http://issues.apache.org/jira/browse/LUCENE-764">LUCENE-764
See Also:   for details):


See Also:   

    See Also:   

  • See Also:   

    If no readers/searchers are open against the index,
    See Also:   then free space required is up to 1X the total size of
    See Also:   the starting index. For example, if the starting
    See Also:   index is 10 GB, then you must have up to 10 GB of free
    See Also:   space before calling optimize.


    See Also:   

  • See Also:   

    If readers/searchers are using the index, then free
    See Also:   space required is up to 2X the size of the starting
    See Also:   index. This is because in addition to the 1X used by
    See Also:   optimize, the original 1X of the starting index is
    See Also:   still consuming space in the Directory as the readers
    See Also:   are holding the segments files open. Even on Unix,
    See Also:   where it will appear as if the files are gone ("ls"
    See Also:   won't list them), they still consume storage due to
    See Also:   "delete on last close" semantics.


    See Also:   

    Furthermore, if some but not all readers re-open
    See Also:   while the optimize is underway, this will cause > 2X
    See Also:   temporary space to be consumed as those new readers
    See Also:   will then hold open the partially optimized segments at
    See Also:   that time. It is best not to re-open readers while
    See Also:   optimize is running.


    See Also:   

See Also:   

The actual temporary usage could be much less than
See Also:   these figures (it depends on many factors).


See Also:   

In general, once the optimize completes, the total size of the
See Also:   index will be less than the size of the starting index.
See Also:   It could be quite a bit smaller (if there were many
See Also:   pending deletes) or just slightly smaller.


See Also:   

If an Exception is hit during optimize(), for example
See Also:   due to disk full, the index will not be corrupt and no
See Also:   documents will have been lost. However, it may have
See Also:   been partially optimized (some segments were merged but
See Also:   not all), and it's possible that one of the segments in
See Also:   the index will be in non-compound format even when
See Also:   using compound file format. This will occur when the
See Also:   Exception is hit during conversion of the segment into
See Also:   compound format.


See Also:   

This call will optimize those segments present in
See Also:   the index when the call started. If other threads are
See Also:   still adding documents and flushing segments, those
See Also:   newly created segments will not be optimized unless you
See Also:   call optimize again.


throws:
  CorruptIndexException - if the index is corrupt
throws:
  IOException - if there is a low-level IO error



optimize
public void optimize(int maxNumSegments) throws CorruptIndexException, IOException(Code)
Optimize the index down to <= maxNumSegments. If maxNumSegments==1 then this is the same as IndexWriter.optimize() .
Parameters:
  maxNumSegments - maximum number of segments leftin the index after optimization finishes



optimize
public void optimize(boolean doWait) throws CorruptIndexException, IOException(Code)
Just like IndexWriter.optimize() , except you can specify whether the call should block until the optimize completes. This is only meaningful with a MergeScheduler that is able to run merges in background threads.



optimize
public void optimize(int maxNumSegments, boolean doWait) throws CorruptIndexException, IOException(Code)
Just like IndexWriter.optimize(int) , except you can specify whether the call should block until the optimize completes. This is only meaningful with a MergeScheduler that is able to run merges in background threads.



ramSizeInBytes
final public long ramSizeInBytes()(Code)
Expert: Return the total size of all index files currently cached in memory. Useful for size management with flushRamDocs()



registerMerge
final synchronized boolean registerMerge(MergePolicy.OneMerge merge)(Code)
Checks whether this merge involves any segments already participating in a merge. If not, this merge is "registered", meaning we record that its segments are now participating in a merge, and true is returned. Else (the merge conflicts) false is returned.



segString
public synchronized String segString()(Code)



setDefaultInfoStream
public static void setDefaultInfoStream(PrintStream infoStream)(Code)
If non-null, this will be the default infoStream used by a newly instantiated IndexWriter.
See Also:   IndexWriter.setInfoStream



setDefaultWriteLockTimeout
public static void setDefaultWriteLockTimeout(long writeLockTimeout)(Code)
Sets the default (for any instance of IndexWriter) maximum time to wait for a write lock (in milliseconds).



setInfoStream
public void setInfoStream(PrintStream infoStream)(Code)
If non-null, information about merges, deletes and a message when maxFieldLength is reached will be printed to this.



setMaxBufferedDeleteTerms
public void setMaxBufferedDeleteTerms(int maxBufferedDeleteTerms)(Code)

Determines the minimal number of delete terms required before the buffered in-memory delete terms are applied and flushed. If there are documents buffered in memory at the time, they are merged and a new segment is created.

Disabled by default (writer flushes by RAM usage).


throws:
  IllegalArgumentException - if maxBufferedDeleteTermsis enabled but smaller than 1
See Also:   IndexWriter.setRAMBufferSizeMB



setMaxBufferedDocs
public void setMaxBufferedDocs(int maxBufferedDocs)(Code)
Determines the minimal number of documents required before the buffered in-memory documents are flushed as a new Segment. Large values generally gives faster indexing.

When this is set, the writer will flush every maxBufferedDocs added documents. Pass in IndexWriter.DISABLE_AUTO_FLUSH to prevent triggering a flush due to number of buffered documents. Note that if flushing by RAM usage is also enabled, then the flush will be triggered by whichever comes first.

Disabled by default (writer flushes by RAM usage).


throws:
  IllegalArgumentException - if maxBufferedDocs isenabled but smaller than 2, or it disables maxBufferedDocswhen ramBufferSize is already disabled
See Also:   IndexWriter.setRAMBufferSizeMB



setMaxFieldLength
public void setMaxFieldLength(int maxFieldLength)(Code)
The maximum number of terms that will be indexed for a single field in a document. This limits the amount of memory required for indexing, so that collections with very large files will not crash the indexing process by running out of memory. This setting refers to the number of running terms, not to the number of different terms.

Note: this silently truncates large documents, excluding from the index all terms that occur further in the document. If you know your source documents are large, be sure to set this value high enough to accomodate the expected size. If you set it to Integer.MAX_VALUE, then the only limit is your memory, but you should anticipate an OutOfMemoryError.

By default, no more than 10,000 terms will be indexed for a field.




setMaxMergeDocs
public void setMaxMergeDocs(int maxMergeDocs)(Code)

Determines the largest segment (measured by document count) that may be merged with other segments. Small values (e.g., less than 10,000) are best for interactive indexing, as this limits the length of pauses while indexing to a few seconds. Larger values are best for batched indexing and speedier searches.

The default value is Integer.MAX_VALUE .

Note that this method is a convenience method: it just calls mergePolicy.setMaxMergeDocs as long as mergePolicy is an instance of LogMergePolicy . Otherwise an IllegalArgumentException is thrown.

The default merge policy ( LogByteSizeMergePolicy ) also allows you to set this limit by net size (in MB) of the segment, using LogByteSizeMergePolicy.setMaxMergeMB .




setMergeFactor
public void setMergeFactor(int mergeFactor)(Code)
Determines how often segment indices are merged by addDocument(). With smaller values, less RAM is used while indexing, and searches on unoptimized indices are faster, but indexing speed is slower. With larger values, more RAM is used during indexing, and while searches on unoptimized indices are slower, indexing is faster. Thus larger values (> 10) are best for batch index creation, and smaller values (< 10) for indices that are interactively maintained.

Note that this method is a convenience method: it just calls mergePolicy.setMergeFactor as long as mergePolicy is an instance of LogMergePolicy . Otherwise an IllegalArgumentException is thrown.

This must never be less than 2. The default value is 10.




setMergePolicy
public void setMergePolicy(MergePolicy mp)(Code)
Expert: set the merge policy used by this writer.



setMergeScheduler
public void setMergeScheduler(MergeScheduler mergeScheduler) throws CorruptIndexException, IOException(Code)
Expert: set the merge scheduler used by this writer.



setRAMBufferSizeMB
public void setRAMBufferSizeMB(double mb)(Code)
Determines the amount of RAM that may be used for buffering added documents before they are flushed as a new Segment. Generally for faster indexing performance it's best to flush by RAM usage instead of document count and use as large a RAM buffer as you can.

When this is set, the writer will flush whenever buffered documents use this much RAM. Pass in IndexWriter.DISABLE_AUTO_FLUSH to prevent triggering a flush due to RAM usage. Note that if flushing by document count is also enabled, then the flush will be triggered by whichever comes first.

The default value is IndexWriter.DEFAULT_RAM_BUFFER_SIZE_MB .


throws:
  IllegalArgumentException - if ramBufferSize isenabled but non-positive, or it disables ramBufferSizewhen maxBufferedDocs is already disabled



setSimilarity
public void setSimilarity(Similarity similarity)(Code)
Expert: Set the Similarity implementation used by this IndexWriter.
See Also:   Similarity.setDefault(Similarity)



setTermIndexInterval
public void setTermIndexInterval(int interval)(Code)
Expert: Set the interval between indexed terms. Large values cause less memory to be used by IndexReader, but slow random-access to terms. Small values cause more memory to be used by an IndexReader, and speed random-access to terms. This parameter determines the amount of computation required per query term, regardless of the number of documents that contain that term. In particular, it is the maximum number of other terms that must be scanned before a term is located and its frequency and position information may be processed. In a large index with user-entered query terms, query processing time is likely to be dominated not by term lookup but rather by the processing of frequency and positional data. In a small index or when many uncommon query terms are generated (e.g., by wildcard queries) term lookup may become a dominant cost. In particular, numUniqueTerms/interval terms are read into memory by an IndexReader, and, on average, interval/2 terms must be scanned for each random term access.
See Also:   IndexWriter.DEFAULT_TERM_INDEX_INTERVAL



setUseCompoundFile
public void setUseCompoundFile(boolean value)(Code)

Setting to turn on usage of a compound file. When on, multiple files for each segment are merged into a single file when a new segment is flushed.

Note that this method is a convenience method: it just calls mergePolicy.setUseCompoundFile as long as mergePolicy is an instance of LogMergePolicy . Otherwise an IllegalArgumentException is thrown.




setWriteLockTimeout
public void setWriteLockTimeout(long writeLockTimeout)(Code)
Sets the maximum time to wait for a write lock (in milliseconds) for this instance of IndexWriter. @see
See Also:   IndexWriter.setDefaultWriteLockTimeout
See Also:    to change the default value for all instances of IndexWriter.



updateDocument
public void updateDocument(Term term, Document doc) throws CorruptIndexException, IOException(Code)
Updates a document by first deleting the document(s) containing term and then adding the new document. The delete and then add are atomic as seen by a reader on the same index (flush may happen only after the add).
Parameters:
  term - the term to identify the document(s) to bedeleted
Parameters:
  doc - the document to be added
throws:
  CorruptIndexException - if the index is corrupt
throws:
  IOException - if there is a low-level IO error



updateDocument
public void updateDocument(Term term, Document doc, Analyzer analyzer) throws CorruptIndexException, IOException(Code)
Updates a document by first deleting the document(s) containing term and then adding the new document. The delete and then add are atomic as seen by a reader on the same index (flush may happen only after the add).
Parameters:
  term - the term to identify the document(s) to bedeleted
Parameters:
  doc - the document to be added
Parameters:
  analyzer - the analyzer to use when analyzing the document
throws:
  CorruptIndexException - if the index is corrupt
throws:
  IOException - if there is a low-level IO error



Methods inherited from java.lang.Object
native protected Object clone() throws CloneNotSupportedException(Code)(Java Doc)
public boolean equals(Object obj)(Code)(Java Doc)
protected void finalize() throws Throwable(Code)(Java Doc)
final native public Class getClass()(Code)(Java Doc)
native public int hashCode()(Code)(Java Doc)
final native public void notify()(Code)(Java Doc)
final native public void notifyAll()(Code)(Java Doc)
public String toString()(Code)(Java Doc)
final native public void wait(long timeout) throws InterruptedException(Code)(Java Doc)
final public void wait(long timeout, int nanos) throws InterruptedException(Code)(Java Doc)
final public void wait() throws InterruptedException(Code)(Java Doc)

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