lucene/core/src/java/org/apache/lucene/document/Document.java - lucene-solr - Git at Google

 /*
  * Licensed to the Apache Software Foundation (ASF) under one or more
  * contributor license agreements.  See the NOTICE file distributed with
  * this work for additional information regarding copyright ownership.
  * The ASF licenses this file to You 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.
  */
 package org.apache.lucene.document;

 import java.util.*;
 import org.apache.lucene.index.IndexReader; // for javadoc
 import org.apache.lucene.index.IndexableField;
 import org.apache.lucene.search.IndexSearcher; // for javadoc
 import org.apache.lucene.search.ScoreDoc; // for javadoc
 import org.apache.lucene.util.BytesRef;

 /**
  * Documents are the unit of indexing and search.
  *
  * <p>A Document is a set of fields. Each field has a name and a textual value. A field may be
  * {@link org.apache.lucene.index.IndexableFieldType#stored() 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
  * org.apache.lucene.index.IndexableFieldType#stored() stored} are <i>not</i> available in documents
  * retrieved from the index, e.g. with {@link ScoreDoc#doc} or {@link IndexReader#document(int)}.
  */
 public final class Document implements Iterable<IndexableField> {

   private final List<IndexableField> fields = new ArrayList<>();

   /** Constructs a new document with no fields. */
   public Document() {}

   @Override
   public Iterator<IndexableField> iterator() {
     return fields.iterator();
   }

   /**
    * 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>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.
    */
   public final void add(IndexableField field) {
     fields.add(field);
   }

   /**
    * 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>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.
    */
   public final void removeField(String name) {
     Iterator<IndexableField> it = fields.iterator();
     while (it.hasNext()) {
       IndexableField field = it.next();
       if (field.name().equals(name)) {
         it.remove();
         return;
       }
     }
   }

   /**
    * Removes all fields with the given name from the document. If there is no field with the
    * specified name, the document remains unchanged.
    *
    * <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.
    */
   public final void removeFields(String name) {
     Iterator<IndexableField> it = fields.iterator();
     while (it.hasNext()) {
       IndexableField field = it.next();
       if (field.name().equals(name)) {
         it.remove();
       }
     }
   }

   /**
    * Returns an array of byte arrays for of the fields that have the name specified as the method
    * parameter. This method returns an empty array when there are no matching fields. It never
    * returns null.
    *
    * @param name the name of the field
    * @return a <code>BytesRef[]</code> of binary field values
    */
   public final BytesRef[] getBinaryValues(String name) {
     final List<BytesRef> result = new ArrayList<>();
     for (IndexableField field : fields) {
       if (field.name().equals(name)) {
         final BytesRef bytes = field.binaryValue();
         if (bytes != null) {
           result.add(bytes);
         }
       }
     }

     return result.toArray(new BytesRef[result.size()]);
   }

   /**
    * 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.
    *
    * @param name the name of the field.
    * @return a <code>BytesRef</code> containing the binary field value or <code>null</code>
    */
   public final BytesRef getBinaryValue(String name) {
     for (IndexableField field : fields) {
       if (field.name().equals(name)) {
         final BytesRef bytes = field.binaryValue();
         if (bytes != null) {
           return bytes;
         }
       }
     }
     return null;
   }

   /**
    * 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.
    */
   public final IndexableField getField(String name) {
     for (IndexableField field : fields) {
       if (field.name().equals(name)) {
         return field;
       }
     }
     return null;
   }

   /**
    * Returns an array of {@link IndexableField}s with the given name. This method returns an empty
    * array when there are no matching fields. It never returns null.
    *
    * @param name the name of the field
    * @return a <code>Field[]</code> array
    */
   public IndexableField[] getFields(String name) {
     List<IndexableField> result = new ArrayList<>();
     for (IndexableField field : fields) {
       if (field.name().equals(name)) {
         result.add(field);
       }
     }

     return result.toArray(new IndexableField[result.size()]);
   }

   /**
    * Returns a List of all the fields in a document.
    *
    * <p>Note that fields which are <i>not</i> stored are <i>not</i> available in documents retrieved
    * from the index, e.g. {@link IndexSearcher#doc(int)} or {@link IndexReader#document(int)}.
    *
    * @return an immutable <code>List&lt;Field&gt;</code>
    */
   public final List<IndexableField> getFields() {
     return Collections.unmodifiableList(fields);
   }

   private static final String[] NO_STRINGS = new String[0];

   /**
    * Returns an array of values of the field specified as the method parameter. This method returns
    * an empty array when there are no matching fields. It never returns null. For a numeric {@link
    * StoredField} it returns the string value of the number. If you want the actual numeric field
    * instances back, use {@link #getFields}.
    *
    * @param name the name of the field
    * @return a <code>String[]</code> of field values
    */
   public final String[] getValues(String name) {
     List<String> result = new ArrayList<>();
     for (IndexableField field : fields) {
       if (field.name().equals(name) && field.stringValue() != null) {
         result.add(field.stringValue());
       }
     }

     if (result.size() == 0) {
       return NO_STRINGS;
     }

     return result.toArray(new String[result.size()]);
   }

   /**
    * 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. For a numeric {@link StoredField} it
    * returns the string value of the number. If you want the actual numeric field instance back, use
    * {@link #getField}.
    */
   public final String get(String name) {
     for (IndexableField field : fields) {
       if (field.name().equals(name) && field.stringValue() != null) {
         return field.stringValue();
       }
     }
     return null;
   }

   /** Prints the fields of a document for human consumption. */
   @Override
   public final String toString() {
     StringBuilder buffer = new StringBuilder();
     buffer.append("Document<");
     for (int i = 0; i < fields.size(); i++) {
       IndexableField field = fields.get(i);
       buffer.append(field.toString());
       if (i != fields.size() - 1) {
         buffer.append(" ");
       }
     }
     buffer.append(">");
     return buffer.toString();
   }

   /** Removes all the fields from document. */
   public void clear() {
     fields.clear();
   }
 }
	/*
	* Licensed to the Apache Software Foundation (ASF) under one or more
	* contributor license agreements. See the NOTICE file distributed with
	* this work for additional information regarding copyright ownership.
	* The ASF licenses this file to You 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.
	*/
	package org.apache.lucene.document;

	import java.util.*;
	import org.apache.lucene.index.IndexReader; // for javadoc
	import org.apache.lucene.index.IndexableField;
	import org.apache.lucene.search.IndexSearcher; // for javadoc
	import org.apache.lucene.search.ScoreDoc; // for javadoc
	import org.apache.lucene.util.BytesRef;

	/**
	* Documents are the unit of indexing and search.
	*
	* <p>A Document is a set of fields. Each field has a name and a textual value. A field may be
	* {@link org.apache.lucene.index.IndexableFieldType#stored() 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
	* org.apache.lucene.index.IndexableFieldType#stored() stored} are <i>not</i> available in documents
	* retrieved from the index, e.g. with {@link ScoreDoc#doc} or {@link IndexReader#document(int)}.
	*/
	public final class Document implements Iterable<IndexableField> {

	private final List<IndexableField> fields = new ArrayList<>();

	/** Constructs a new document with no fields. */
	public Document() {}

	@Override
	public Iterator<IndexableField> iterator() {
	return fields.iterator();
	}

	/**
	* 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>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.
	*/
	public final void add(IndexableField field) {
	fields.add(field);
	}

	/**
	* 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>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.
	*/
	public final void removeField(String name) {
	Iterator<IndexableField> it = fields.iterator();
	while (it.hasNext()) {
	IndexableField field = it.next();
	if (field.name().equals(name)) {
	it.remove();
	return;
	}
	}
	}

	/**
	* Removes all fields with the given name from the document. If there is no field with the
	* specified name, the document remains unchanged.
	*
	* <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.
	*/
	public final void removeFields(String name) {
	Iterator<IndexableField> it = fields.iterator();
	while (it.hasNext()) {
	IndexableField field = it.next();
	if (field.name().equals(name)) {
	it.remove();
	}
	}
	}

	/**
	* Returns an array of byte arrays for of the fields that have the name specified as the method
	* parameter. This method returns an empty array when there are no matching fields. It never
	* returns null.
	*
	* @param name the name of the field
	* @return a <code>BytesRef[]</code> of binary field values
	*/
	public final BytesRef[] getBinaryValues(String name) {
	final List<BytesRef> result = new ArrayList<>();
	for (IndexableField field : fields) {
	if (field.name().equals(name)) {
	final BytesRef bytes = field.binaryValue();
	if (bytes != null) {
	result.add(bytes);
	}
	}
	}

	return result.toArray(new BytesRef[result.size()]);
	}

	/**
	* 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.
	*
	* @param name the name of the field.
	* @return a <code>BytesRef</code> containing the binary field value or <code>null</code>
	*/
	public final BytesRef getBinaryValue(String name) {
	for (IndexableField field : fields) {
	if (field.name().equals(name)) {
	final BytesRef bytes = field.binaryValue();
	if (bytes != null) {
	return bytes;
	}
	}
	}
	return null;
	}

	/**
	* 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.
	*/
	public final IndexableField getField(String name) {
	for (IndexableField field : fields) {
	if (field.name().equals(name)) {
	return field;
	}
	}
	return null;
	}

	/**
	* Returns an array of {@link IndexableField}s with the given name. This method returns an empty
	* array when there are no matching fields. It never returns null.
	*
	* @param name the name of the field
	* @return a <code>Field[]</code> array
	*/
	public IndexableField[] getFields(String name) {
	List<IndexableField> result = new ArrayList<>();
	for (IndexableField field : fields) {
	if (field.name().equals(name)) {
	result.add(field);
	}
	}

	return result.toArray(new IndexableField[result.size()]);
	}

	/**
	* Returns a List of all the fields in a document.
	*
	* <p>Note that fields which are <i>not</i> stored are <i>not</i> available in documents retrieved
	* from the index, e.g. {@link IndexSearcher#doc(int)} or {@link IndexReader#document(int)}.
	*
	* @return an immutable <code>List<Field></code>
	*/
	public final List<IndexableField> getFields() {
	return Collections.unmodifiableList(fields);
	}

	private static final String[] NO_STRINGS = new String[0];

	/**
	* Returns an array of values of the field specified as the method parameter. This method returns
	* an empty array when there are no matching fields. It never returns null. For a numeric {@link
	* StoredField} it returns the string value of the number. If you want the actual numeric field
	* instances back, use {@link #getFields}.
	*
	* @param name the name of the field
	* @return a <code>String[]</code> of field values
	*/
	public final String[] getValues(String name) {
	List<String> result = new ArrayList<>();
	for (IndexableField field : fields) {
	if (field.name().equals(name) && field.stringValue() != null) {
	result.add(field.stringValue());
	}
	}

	if (result.size() == 0) {
	return NO_STRINGS;
	}

	return result.toArray(new String[result.size()]);
	}

	/**
	* 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. For a numeric {@link StoredField} it
	* returns the string value of the number. If you want the actual numeric field instance back, use
	* {@link #getField}.
	*/
	public final String get(String name) {
	for (IndexableField field : fields) {
	if (field.name().equals(name) && field.stringValue() != null) {
	return field.stringValue();
	}
	}
	return null;
	}

	/** Prints the fields of a document for human consumption. */
	@Override
	public final String toString() {
	StringBuilder buffer = new StringBuilder();
	buffer.append("Document<");
	for (int i = 0; i < fields.size(); i++) {
	IndexableField field = fields.get(i);
	buffer.append(field.toString());
	if (i != fields.size() - 1) {
	buffer.append(" ");
	}
	}
	buffer.append(">");
	return buffer.toString();
	}

	/** Removes all the fields from document. */
	public void clear() {
	fields.clear();
	}
	}