package org.farng.mp3;
import java.io.IOException;
import java.io.RandomAccessFile;
import java.util.ArrayList;
import java.util.Iterator;
import java.util.List;
import org.farng.mp3.id3.ID3v2_2;
import org.farng.mp3.id3.ID3v2_3;
import org.farng.mp3.id3.ID3v2_4;
import org.farng.mp3.object.AbstractMP3Object;
/**
* This class is contained in the <code>AbstractMP3Fragment</code> and represents the actual data of tags. It contains
* default get/set methods for all data objects. The data is represented as an ArrayList of <code>MP3Object</code>.
* ID3v2 tags have frames. Lyrics3 tags have fields. ID3v1 tags do not have fragments.
*
* @author Eric Farng
* @version $Revision: 2374 $
*/
public abstract class AbstractMP3FragmentBody extends AbstractMP3FileItem {
private static final int SIZE_OBJECT_LIST = 16;
private static final int SIZE_BRIEF_DESCRIPTION = 64;
private static final int SIZE_DESCRIPTION = 256;
/**
* list of <code>MP3Object</code>
*/
private List objectList = new ArrayList(AbstractMP3FragmentBody.SIZE_OBJECT_LIST);
/**
* Creates a new MP3FragmentBody object.
*/
protected AbstractMP3FragmentBody() {
super();
setupObjectList();
}
/**
* Creates a new AbstractMP3FragmentBody object.
*/
protected AbstractMP3FragmentBody(final AbstractMP3FragmentBody copyObject) {
super(copyObject);
final Iterator iterator = copyObject.iterator();
while (iterator.hasNext()) {
final AbstractMP3Object oldObject = (AbstractMP3Object) iterator.next();
final AbstractMP3Object newObject = (AbstractMP3Object) TagUtility.copyObject(oldObject);
objectList.add(newObject);
}
}
/**
* This method calls <code>toString</code> for all it's objects and appends them without any newline characters.
*
* @return brief description string
*/
public String getBriefDescription() {
final StringBuffer stringBuffer = new StringBuffer(AbstractMP3FragmentBody.SIZE_BRIEF_DESCRIPTION);
final Iterator iterator = objectList.listIterator();
while (iterator.hasNext()) {
final AbstractMP3Object object = (AbstractMP3Object) iterator.next();
final String objectToString = object.toString();
if (objectToString != null && objectToString.length() > 0) {
final String identifier = object.getIdentifier();
stringBuffer.append(identifier);
stringBuffer.append("=\"");
stringBuffer.append(objectToString);
stringBuffer.append("\"; ");
}
}
return stringBuffer.toString();
}
/**
* This method calls <code>toString</code> for all it's objects and appends them. It contains new line characters
* and is more suited for display purposes
*
* @return formatted description string
*/
public String getDescription() {
final StringBuffer stringBuffer = new StringBuffer(AbstractMP3FragmentBody.SIZE_DESCRIPTION);
final Iterator iterator = objectList.listIterator();
while (iterator.hasNext()) {
final AbstractMP3Object object = (AbstractMP3Object) iterator.next();
final String identifier = object.getIdentifier();
stringBuffer.append(identifier);
stringBuffer.append(" = ");
final String string = object.toString();
stringBuffer.append(string);
stringBuffer.append(TagConstant.SEPERATOR_LINE);
}
final String toString = stringBuffer.toString();
return toString.trim();
}
public Iterator getObjectListIterator() {
return objectList.listIterator();
}
/**
* Sets the all objects of identifier type to <code>object</code> argument.
*
* @param identifier <code>MP3Object</code> identifier
* @param object new object value
*/
public void setObject(final String identifier, final Object object) {
final Iterator iterator = objectList.listIterator();
while (iterator.hasNext()) {
final AbstractMP3Object abstractMP3Object = (AbstractMP3Object) iterator.next();
final String currentIdentifier = abstractMP3Object.getIdentifier();
if (currentIdentifier.equals(identifier)) {
abstractMP3Object.setValue(object);
}
}
}
/**
* Returns the object of the <code>MP3Object</code> with the specified <code>identifier</code>
*
* @param identifier <code>MP3Object</code> identifier
*
* @return the object of the <code>MP3Object</code> with the specified <code>identifier</code>
*/
public Object getObject(final String identifier) {
Object object = null;
final Iterator iterator = objectList.listIterator();
while (iterator.hasNext()) {
final AbstractMP3Object abstractMP3Object = (AbstractMP3Object) iterator.next();
final String currentIdentifier = abstractMP3Object.getIdentifier();
if (currentIdentifier.equals(identifier)) {
object = abstractMP3Object.getValue();
}
}
return object;
}
/**
* Returns the estimated size in bytes of this object if it was to be written to file. This is not guaranteed to be
* accurate 100% of the time.
*
* @return estimated size in bytes of this object
*/
public int getSize() {
//todo get this working 100% of the time
int size = 0;
final Iterator iterator = objectList.listIterator();
while (iterator.hasNext()) {
final AbstractMP3Object object = (AbstractMP3Object) iterator.next();
size += object.getSize();
}
return size;
}
/**
* Returns true if this instance and its entire <code>MP3Object</code> array list is a subset of the argument. This
* class is a subset if it is the same class as the argument.
*
* @param object object to determine subset of
*
* @return true if this instance and its entire object array list is a subset of the argument.
*/
public boolean isSubsetOf(final Object object) {
if (!super.isSubsetOf(object)) {
return false;
}
if (!(object instanceof AbstractMP3FragmentBody)) {
return false;
}
final List superset = ((AbstractMP3FragmentBody) object).objectList;
final int objectListSize = objectList.size();
for (int i = 0; i < objectListSize; i++) {
final AbstractMP3Object abstractMP3Object = (AbstractMP3Object) objectList.get(i);
if (abstractMP3Object.getValue() != null && !superset.contains(abstractMP3Object)) {
return false;
}
}
return true;
}
/**
* Returns true if this object and its entire <code>MP3Object</code> array list equals the argument. This object is
* equal to the argument only if they are the same class.
*
* @param obj object to determine equality of
*
* @return true if this object and its entire <code>MP3Object</code> array list equals the argument.
*/
public boolean equals(final Object obj) {
if (!(obj instanceof AbstractMP3FragmentBody)) {
return false;
}
final AbstractMP3FragmentBody abstractMP3FragmentBody = (AbstractMP3FragmentBody) obj;
if (!objectList.equals(abstractMP3FragmentBody.objectList)) {
return false;
}
return super.equals(obj);
}
/**
* Returns an iterator of the <code>MP3Object</code> object list.
*
* @return iterator of the <code>MP3Object</code> object list.
*/
public Iterator iterator() {
return objectList.iterator();
}
protected void appendToObjectList(final AbstractMP3Object object) {
objectList.add(object);
}
/**
* Read the data from the given file into this object. The file needs to have its file pointer in the correct
* location.
*
* @param file file to read from
*
* @throws IOException on any I/O error
* @throws InvalidTagException if there is any error in the data format.
*/
public void read(final RandomAccessFile file) throws IOException, InvalidTagException {
final int size = readHeader(file);
final byte[] buffer = new byte[size];
file.read(buffer);
final Iterator iterator = objectList.listIterator();
int offset = 0;
while (iterator.hasNext()) {
// sanjay@revasoft.com start bug fix
if (offset > size - 1) {
throw new InvalidTagException("Invalid size for Frame Body");
}
// sanjay@revasoft.com end bug fix
final AbstractMP3Object object = (AbstractMP3Object) iterator.next();
object.readByteArray(buffer, offset);
offset += object.getSize();
}
}
/**
* Calls <code>toString</code> for all <code>MP3Object</code> objects and creates a string with a new line
* character.
*
* @return description string
*/
public String toString() {
final StringBuffer stringBuffer = new StringBuffer(AbstractMP3FragmentBody.SIZE_DESCRIPTION);
final String thisIdentifier = getIdentifier();
stringBuffer.append(thisIdentifier);
stringBuffer.append(TagConstant.SEPERATOR_LINE);
final Iterator iterator = objectList.listIterator();
while (iterator.hasNext()) {
final AbstractMP3Object object = (AbstractMP3Object) iterator.next();
final String objectIdentifier = object.getIdentifier();
stringBuffer.append(objectIdentifier);
stringBuffer.append(" = ");
final String string = object.toString();
stringBuffer.append(string);
stringBuffer.append(TagConstant.SEPERATOR_LINE);
}
return stringBuffer.toString();
}
/**
* Write the contents of this object to the file at the position it is currently at.
*
* @param file destination file
*
* @throws IOException on any I/O error
*/
public void write(final RandomAccessFile file) throws IOException {
final int size = getSize();
writeHeader(file, size);
final Iterator iterator = objectList.listIterator();
while (iterator.hasNext()) {
final AbstractMP3Object object = (AbstractMP3Object) iterator.next();
final byte[] buffer = object.writeByteArray();
file.write(buffer);
}
}
/**
* Reads the header for the fragment body. The header contains things such as the length.
*
* @param file file to read the header from.
*
* @return size of body in bytes as stated in the header.
*
* @throws IOException on any I/O error
* @throws InvalidTagException if there is any error in the data format.
*/
protected abstract int readHeader(RandomAccessFile file) throws IOException, InvalidTagException;
/**
* Create the order of <code>MP3Object</code> objects that this body expects. This method needs to be overwritten.
*/
protected abstract void setupObjectList();
/**
* Write the body header to the file at the current file position.
*
* @param file file to write to
* @param size number of bytes the body contains.
*
* @throws IOException on any I/O error
*/
protected abstract void writeHeader(RandomAccessFile file, int size) throws IOException;
protected static boolean has6ByteHeader() {
final Exception exception = new Exception();
final StackTraceElement[] stackArray = exception.getStackTrace();
final String id3v2_2name = ID3v2_2.class.getName();
final String id3v2_3name = ID3v2_3.class.getName();
final String id3v2_4name = ID3v2_4.class.getName();
boolean has6ByteHeader = false;
boolean withinTag = false;
for (int i = stackArray.length - 1; i >= 0; i--) {
final String className = stackArray[i].getClassName();
if (id3v2_2name.equals(className)) {
has6ByteHeader = true;
withinTag = true;
} else if (id3v2_3name.equals(className)) {
has6ByteHeader = false;
withinTag = true;
} else if (id3v2_4name.equals(className)) {
has6ByteHeader = false;
withinTag = true;
}
}
if (!withinTag) {
throw new UnsupportedOperationException("FragmentBody not called within ID3v2 tag.");
}
return has6ByteHeader;
}
}