/**
* @author : Paul Taylor
* @author : Eric Farng
*
* Version @version:$Id: AbstractFrameBodyTextInfo.java 895 2010-04-15 15:21:45Z paultaylor $
*
* MusicTag Copyright (C)2003,2004
*
* This library is free software; you can redistribute it and/or modify it under the terms of the GNU Lesser
* General Public License as published by the Free Software Foundation; either version 2.1 of the License,
* or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even
* the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
* See the GNU Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public License along with this library; if not,
* you can get a copy from http://www.opensource.org/licenses/lgpl-license.php or write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*
* Description:
*/
package org.jaudiotagger.tag.id3.framebody;
import org.jaudiotagger.logging.ErrorMessage;
import org.jaudiotagger.tag.InvalidTagException;
import org.jaudiotagger.tag.datatype.DataTypes;
import org.jaudiotagger.tag.datatype.NumberHashMap;
import org.jaudiotagger.tag.datatype.TextEncodedStringSizeTerminated;
import org.jaudiotagger.tag.id3.ID3TextEncodingConversion;
import org.jaudiotagger.tag.id3.valuepair.TextEncoding;
import java.io.ByteArrayOutputStream;
import java.nio.ByteBuffer;
/**
* Abstract representation of a Text Frame
* <p/>
* The text information frames are often the most important frames, containing information like artist, album and
* more. There may only be one text information frame of its kind in an tag. In ID3v24 All text information frames
* supports multiple strings, stored as a null separated list, where null is represented by the termination code
* for the character encoding. All text frame identifiers begin with "T". Only text frame identifiers begin with "T",
* with the exception of the "TXXX" frame. All the text information frames have the following format:
* <Header for 'Text information frame', ID: "T000" - "TZZZ",
* excluding "TXXX" described in 4.2.6.>
* Text encoding $xx
* Information <text string(s) according to encoding>
* <p/>
* The list of valid text encodings increased from two in ID3v23 to four in ID3v24
* <p/>
* iTunes incorrectly writes null terminators at the end of every String, even though it only writes one String.
* <p/>
* You can retrieve the first value without the null terminator using {@link #getFirstTextValue}
*/
public abstract class AbstractFrameBodyTextInfo extends AbstractID3v2FrameBody
{
/**
* Creates a new FrameBodyTextInformation datatype. The super.super
* Constructor sets up the Object list for the frame.
*/
protected AbstractFrameBodyTextInfo()
{
super();
setObjectValue(DataTypes.OBJ_TEXT_ENCODING, TextEncoding.ISO_8859_1);
setObjectValue(DataTypes.OBJ_TEXT, "");
}
/**
* Copy Constructor
*
* @param body AbstractFrameBodyTextInformation
*/
protected AbstractFrameBodyTextInfo(AbstractFrameBodyTextInfo body)
{
super(body);
}
/**
* Creates a new FrameBodyTextInformation data type. This is used when user
* wants to create a new frame based on data in a user interface.
*
* @param textEncoding Specifies what encoding should be used to write
* text to file.
* @param text Specifies the text String.
*/
protected AbstractFrameBodyTextInfo(byte textEncoding, String text)
{
super();
setObjectValue(DataTypes.OBJ_TEXT_ENCODING, textEncoding);
setObjectValue(DataTypes.OBJ_TEXT, text);
}
/**
* Creates a new FrameBodyTextInformation data type from file.
* <p/>
* <p>The super.super Constructor sets up the Object list for the frame.
*
* @param byteBuffer
* @param frameSize
* @throws InvalidTagException if unable to create framebody from buffer
*/
protected AbstractFrameBodyTextInfo(ByteBuffer byteBuffer, int frameSize) throws InvalidTagException
{
super(byteBuffer, frameSize);
}
/**
* Set the Full Text String.
* <p/>
* <p>If this String contains null terminator characters these are parsed as value
* separators, allowing you to hold multiple strings within one text frame. This functionality is only
* officially support in ID3v24.
*
* @param text to set
*/
public void setText(String text)
{
if (text == null)
{
throw new IllegalArgumentException(ErrorMessage.GENERAL_INVALID_NULL_ARGUMENT.getMsg());
}
setObjectValue(DataTypes.OBJ_TEXT, text);
}
public String getUserFriendlyValue()
{
return getTextWithoutTrailingNulls();
}
/**
* Retrieve the complete text String as it is held internally.
*
* If multiple values are held these wil be returned, needless trailing nulls will also be returned
*
* @return the text string
*/
public String getText()
{
return (String) getObjectValue(DataTypes.OBJ_TEXT);
}
/**
* Retrieve the complete text String but without any trailing nulls
*
* If multiple values are held these will be returned, needless trailing nulls will not be returned
*
* @return the text string
*/
public String getTextWithoutTrailingNulls()
{
TextEncodedStringSizeTerminated text = (TextEncodedStringSizeTerminated) getObject(DataTypes.OBJ_TEXT);
return text.getValueWithoutTrailingNull();
}
/**
* Get first value
*
* @return value at index 0
*/
public String getFirstTextValue()
{
TextEncodedStringSizeTerminated text = (TextEncodedStringSizeTerminated) getObject(DataTypes.OBJ_TEXT);
return text.getValueAtIndex(0);
}
/**
* Get text value at index
*
* When a multiple values are stored within a single text frame this method allows access to any of the
* individual values.
*
* @param index
* @return value at index
*/
public String getValueAtIndex(int index)
{
TextEncodedStringSizeTerminated text = (TextEncodedStringSizeTerminated) getObject(DataTypes.OBJ_TEXT);
return text.getValueAtIndex(index);
}
/**
* Add additional value to value
*
* @param value at index
*/
public void addTextValue(String value)
{
TextEncodedStringSizeTerminated text = (TextEncodedStringSizeTerminated) getObject(DataTypes.OBJ_TEXT);
text.addValue(value);
}
/**
* @return number of text values, usually one
*/
public int getNumberOfValues()
{
TextEncodedStringSizeTerminated text = (TextEncodedStringSizeTerminated) getObject(DataTypes.OBJ_TEXT);
return text.getNumberOfValues();
}
/**
* Because Text frames have a text encoding we need to check the text
* String does not contain characters that cannot be encoded in
* current encoding before we write data. If there are change the text
* encoding.
*/
public void write(ByteArrayOutputStream tagBuffer)
{
//Ensure valid for type
setTextEncoding(ID3TextEncodingConversion.getTextEncoding(getHeader(), getTextEncoding()));
//Ensure valid for data
if (!((TextEncodedStringSizeTerminated) getObject(DataTypes.OBJ_TEXT)).canBeEncoded())
{
this.setTextEncoding(ID3TextEncodingConversion.getUnicodeTextEncoding(getHeader()));
}
super.write(tagBuffer);
}
/**
* Setup the Object List. All text frames contain a text encoding
* and then a text string.
* <p/>
* TODO:would like to make final but cannot because overridden by FrameBodyTXXX
*/
protected void setupObjectList()
{
objectList.add(new NumberHashMap(DataTypes.OBJ_TEXT_ENCODING, this, TextEncoding.TEXT_ENCODING_FIELD_SIZE));
objectList.add(new TextEncodedStringSizeTerminated(DataTypes.OBJ_TEXT, this));
}
}
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