|
| |
|
| java.lang.Object
 java.io.Reader
| Reader | | abstract public class Reader implements Readable,Closeable(Code) | | Reader is an Abstract class for reading Character Streams. Subclasses of
Reader must implement the methods read(char[], int, int) and
close().
See Also: Writer |
| Field Summary | |
| protected Object | lock
The object used to synchronize access to the reader. |
| Constructor Summary | |
| protected | Reader()
Constructs a new character stream Reader using this as the
Object to synchronize critical regions around. | | protected | Reader(Object lock)
Constructs a new character stream Reader using lock as the
Object to synchronize critical regions around. |
| Method Summary | |
| abstract public void | close()
Close this Reader. | | public void | mark(int readLimit)
Set a Mark position in this Reader. | | public boolean | markSupported()
Answers a boolean indicating whether or not this Reader supports mark()
and reset(). | | public int | read()
Reads a single character from this reader and returns the result as an
int. | | public int | read(char buf)
Reads characters from this Reader and stores them in the character array
buf starting at offset 0. | | abstract public int | read(char buf, int offset, int count)
Reads at most count characters from this Reader and stores
them at offset in the character array buf. | | public int | read(CharBuffer target)
Read chars from the Reader and then put them to the target
CharBuffer. | | public boolean | ready()
Answers a boolean indicating whether or not this Reader is
ready to be read without blocking. | | public void | reset()
Reset this Readers position to the last mark() location.
Invocations of read()/skip() will occur from this new
location. | | public long | skip(long count)
Skips count number of characters in this Reader.
Subsequent read()'s will not return these characters
unless reset() is used. |
| lock | | protected Object lock(Code) | | The object used to synchronize access to the reader.
|
| Reader | | protected Reader()(Code) | | Constructs a new character stream Reader using this as the
Object to synchronize critical regions around.
|
| Reader | | protected Reader(Object lock)(Code) | | Constructs a new character stream Reader using lock as the
Object to synchronize critical regions around.
Parameters:
lock - the Object to synchronize critical regionsaround. |
| close | | abstract public void close() throws IOException(Code) | | Close this Reader. This must be implemented by any concrete subclasses.
The implementation should free any resources associated with the Reader.
throws:
IOException - If an error occurs attempting to close this Reader. |
| mark | | public void mark(int readLimit) throws IOException(Code) | | Set a Mark position in this Reader. The parameter readLimit
indicates how many characters can be read before a mark is invalidated.
Sending reset() will reposition the reader back to the marked position
provided readLimit has not been surpassed.
This default implementation simply throws IOException and concrete
subclasses must provide their own implementations.
Parameters:
readLimit - an int representing how many characters must be read beforeinvalidating the mark.
throws:
IOException - If an error occurs attempting mark this Reader. |
| markSupported | | public boolean markSupported()(Code) | | Answers a boolean indicating whether or not this Reader supports mark()
and reset(). This class a default implementation which answers false.
true if mark() and reset() are supported,false otherwise. This implementation returnsfalse. |
| read | | public int read() throws IOException(Code) | | Reads a single character from this reader and returns the result as an
int. The 2 higher-order characters are set to 0. If the end of reader was
encountered then return -1.
the character read or -1 if end of reader.
throws:
IOException - If the Reader is already closed or some other IO erroroccurs. |
| read | | public int read(char buf) throws IOException(Code) | | Reads characters from this Reader and stores them in the character array
buf starting at offset 0. Returns the number of characters
actually read or -1 if the end of reader was encountered.
Parameters:
buf - character array to store the read characters how many characters were successfully read in or else -1 if theend of the reader was detected.
throws:
IOException - If the Reader is already closed or some other IO erroroccurs. |
| read | | abstract public int read(char buf, int offset, int count) throws IOException(Code) | | Reads at most count characters from this Reader and stores
them at offset in the character array buf.
Returns the number of characters actually read or -1 if the end of reader
was encountered.
Parameters:
buf - character array to store the read characters
Parameters:
offset - offset in buf to store the read characters
Parameters:
count - how many characters should be read in how many characters were successfully read in or else -1 if theend of the reader was detected.
throws:
IOException - If the Reader is already closed or some other IO erroroccurs. |
| read | | public int read(CharBuffer target) throws IOException(Code) | | Read chars from the Reader and then put them to the target
CharBuffer. Only put method is called on the target.
Parameters:
target - the destination CharBuffer the actual number of chars put to the target. -1when the Reader has reached the end before the method is called.
throws:
IOException - if any I/O error raises in the procedure
throws:
NullPointerException - if the target CharBuffer is null
throws:
ReadOnlyBufferException - if the target CharBuffer is readonly |
| ready | | public boolean ready() throws IOException(Code) | | Answers a boolean indicating whether or not this Reader is
ready to be read without blocking. If the result is true,
the next read() will not block. If the result is
false this Reader may or may not block when
read() is sent.
true if the receiver will not block whenread() is called, false if unknownor blocking will occur.
throws:
IOException - If the Reader is already closed or some other IO erroroccurs. |
| reset | | public void reset() throws IOException(Code) | | Reset this Readers position to the last mark() location.
Invocations of read()/skip() will occur from this new
location. If this Reader was not marked, the implementation of
reset() is implementation specific. See the comment for
the specific Reader subclass for implementation details. The default
action is to throw IOException.
throws:
IOException - If a problem occurred or the receiver does not supportmark()/reset(). |
| skip | | public long skip(long count) throws IOException(Code) | | Skips count number of characters in this Reader.
Subsequent read()'s will not return these characters
unless reset() is used. This method may perform multiple
reads to read count characters.
Parameters:
count - how many characters should be passed over how many characters were successfully passed over
throws:
IOException - If the Reader is closed when the call is made or if an IOerror occurs during the operation. |
|
|
|