/*
* Copyright 2004 The Apache Software Foundation
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
using System;
using IndexReaderLucene.Net.Index.IndexReader;
using HitsLucene.Net.Search.Hits;
using SearcherLucene.Net.Search.Searcher;
namespace Lucene.Net.Documents{
/// <summary>Documents are the unit of indexing and search.
///
/// A Document is a set of fields. Each field has a name and a textual value.
/// A field may be {@link Field#IsStored() stored} with the document, in which
/// case it is returned with search hits on the document. Thus each document
/// should typically contain one or more stored fields which uniquely identify
/// it.
///
/// <p>Note that fields which are <i>not</i> {@link Field#IsStored() stored} are
/// <i>not</i> available in documents retrieved from the index, e.g. with {@link
/// Hits#Doc(int)}, {@link Searcher#Doc(int)} or {@link
/// IndexReader#Document(int)}.
/// </summary>
[Serializable]
public sealed class Document
{
internal System.Collections.IList fields = System.Collections.ArrayList.Synchronized(new System.Collections.ArrayList(10));
private float boost = 1.0f;
/// <summary>Constructs a new document with no fields. </summary>
public Document()
{
}
/// <summary>Sets a boost factor for hits on any field of this document. This value
/// will be multiplied into the score of all hits on this document.
///
/// <p>Values are multiplied into the value of {@link Field#GetBoost()} of
/// each field in this document. Thus, this method in effect sets a default
/// boost for the fields of this document.
///
/// </summary>
/// <seealso cref="Field.SetBoost(float)">
/// </seealso>
public void SetBoost(float boost)
{
this.boost = boost;
}
/// <summary>Returns the boost factor for hits on any field of this document.
///
/// <p>The default value is 1.0.
///
/// <p>Note: This value is not stored directly with the document in the index.
/// Documents returned from {@link IndexReader#Document(int)} and
/// {@link Hits#Doc(int)} may thus not have the same value present as when
/// this document was indexed.
///
/// </summary>
/// <seealso cref="SetBoost(float)">
/// </seealso>
public float GetBoost()
{
return boost;
}
/// <summary> <p>Adds a field to a document. Several fields may be added with
/// the same name. In this case, if the fields are indexed, their text is
/// treated as though appended for the purposes of search.</p>
/// <p> Note that add like the removeField(s) methods only makes sense
/// prior to adding a document to an index. These methods cannot
/// be used to change the content of an existing index! In order to achieve this,
/// a document has to be deleted from an index and a new changed version of that
/// document has to be added.</p>
/// </summary>
public void Add(Field field)
{
fields.Add(field);
}
/// <summary> <p>Removes field with the specified name from the document.
/// If multiple fields exist with this name, this method removes the first field that has been added.
/// If there is no field with the specified name, the document remains unchanged.</p>
/// <p> Note that the removeField(s) methods like the add method only make sense
/// prior to adding a document to an index. These methods cannot
/// be used to change the content of an existing index! In order to achieve this,
/// a document has to be deleted from an index and a new changed version of that
/// document has to be added.</p>
/// </summary>
public void RemoveField(System.String name)
{
System.Collections.IEnumerator it = fields.GetEnumerator();
while (it.MoveNext())
{
Field field = (Field) it.Current;
if (field.Name().Equals(name))
{
fields.Remove(field);
return ;
}
}
}
/// <summary> <p>Removes all fields with the given name from the document.
/// If there is no field with the specified name, the document remains unchanged.</p>
/// <p> Note that the removeField(s) methods like the add method only make sense
/// prior to adding a document to an index. These methods cannot
/// be used to change the content of an existing index! In order to achieve this,
/// a document has to be deleted from an index and a new changed version of that
/// document has to be added.</p>
/// </summary>
public void RemoveFields(System.String name)
{
System.Collections.IEnumerator it = fields.GetEnumerator();
while (it.MoveNext())
{
Field field = (Field) it.Current;
if (field.Name().Equals(name))
{
fields.Remove(field);
}
}
}
/// <summary>Returns a field with the given name if any exist in this document, or
/// null. If multiple fields exists with this name, this method returns the
/// first value added.
/// </summary>
public Field GetField(System.String name)
{
for (int i = 0; i < fields.Count; i++)
{
Field field = (Field) fields[i];
if (field.Name().Equals(name))
return field;
}
return null;
}
/// <summary>Returns the string value of the field with the given name if any exist in
/// this document, or null. If multiple fields exist with this name, this
/// method returns the first value added. If only binary fields with this name
/// exist, returns null.
/// </summary>
public System.String Get(System.String name)
{
for (int i = 0; i < fields.Count; i++)
{
Field field = (Field) fields[i];
if (field.Name().Equals(name) && (!field.IsBinary()))
return field.StringValue();
}
return null;
}
/// <summary>Returns an Enumeration of all the fields in a document. </summary>
public System.Collections.IEnumerator Fields()
{
return ((System.Collections.ArrayList) fields).GetEnumerator();
}
/// <summary> Returns an array of {@link Field}s with the given name.
/// This method can return <code>null</code>.
///
/// </summary>
/// <param name="name">the name of the field
/// </param>
/// <returns> a <code>Field[]</code> array
/// </returns>
public Field[] GetFields(System.String name)
{
System.Collections.ArrayList result = new System.Collections.ArrayList();
for (int i = 0; i < fields.Count; i++)
{
Field field = (Field) fields[i];
if (field.Name().Equals(name))
{
result.Add(field);
}
}
if (result.Count == 0)
return null;
return (Field[]) result.ToArray(typeof(Field));
}
/// <summary> Returns an array of values of the field specified as the method parameter.
/// This method can return <code>null</code>.
///
/// </summary>
/// <param name="name">the name of the field
/// </param>
/// <returns> a <code>String[]</code> of field values
/// </returns>
public System.String[] GetValues(System.String name)
{
System.Collections.ArrayList result = new System.Collections.ArrayList();
for (int i = 0; i < fields.Count; i++)
{
Field field = (Field) fields[i];
if (field.Name().Equals(name) && (!field.IsBinary()))
result.Add(field.StringValue());
}
if (result.Count == 0)
return null;
return (System.String[]) (result.ToArray(typeof(System.String)));
}
/// <summary> Returns an array of byte arrays for of the fields that have the name specified
/// as the method parameter. This method will return <code>null</code> if no
/// binary fields with the specified name are available.
///
/// </summary>
/// <param name="name">the name of the field
/// </param>
/// <returns> a <code>byte[][]</code> of binary field values.
/// </returns>
public byte[][] GetBinaryValues(System.String name)
{
System.Collections.IList result = new System.Collections.ArrayList();
for (int i = 0; i < fields.Count; i++)
{
Field field = (Field) fields[i];
if (field.Name().Equals(name) && (field.IsBinary()))
{
byte[] byteArray = field.BinaryValue();
byte[] resultByteArray = new byte[byteArray.Length];
for (int index = 0; index < byteArray.Length; index++)
resultByteArray[index] = (byte) byteArray[index];
result.Add(resultByteArray);
}
}
if (result.Count == 0)
return null;
System.Collections.ICollection c = result;
System.Object[] objects = new byte[result.Count][];
System.Type type = objects.GetType().GetElementType();
System.Object[] objs = (System.Object[]) Array.CreateInstance(type, c.Count );
System.Collections.IEnumerator e = c.GetEnumerator();
int ii = 0;
while (e.MoveNext())
objs[ii++] = e.Current;
// If objects is smaller than c then do not return the new array in the parameter
if (objects.Length >= c.Count)
objs.CopyTo(objects, 0);
return (byte[][]) objs;
}
/// <summary> Returns an array of bytes for the first (or only) field that has the name
/// specified as the method parameter. This method will return <code>null</code>
/// if no binary fields with the specified name are available.
/// There may be non-binary fields with the same name.
///
/// </summary>
/// <param name="name">the name of the field.
/// </param>
/// <returns> a <code>byte[]</code> containing the binary field value.
/// </returns>
public byte[] GetBinaryValue(System.String name)
{
for (int i = 0; i < fields.Count; i++)
{
Field field = (Field) fields[i];
if (field.Name().Equals(name) && (field.IsBinary()))
return field.BinaryValue();
}
return null;
}
/// <summary>Prints the fields of a document for human consumption. </summary>
public override System.String ToString()
{
System.Text.StringBuilder buffer = new System.Text.StringBuilder();
buffer.Append("Document<");
for (int i = 0; i < fields.Count; i++)
{
Field field = (Field) fields[i];
buffer.Append(field.ToString());
if (i != fields.Count - 1)
buffer.Append(" ");
}
buffer.Append(">");
return buffer.ToString();
}
}
}
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