/*
* DoABC.java
* Transform
*
* Copyright (c) 2009-2010 Flagstone Software Ltd. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
*
* * Redistributions of source code must retain the above copyright notice,
* this list of conditions and the following disclaimer.
* * Redistributions in binary form must reproduce the above copyright notice,
* this list of conditions and the following disclaimer in the documentation
* and/or other materials provided with the distribution.
* * Neither the name of Flagstone Software Ltd. nor the names of its
* contributors may be used to endorse or promote products derived from this
* software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
* LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*/
package com.flagstone.transform;
import java.io.IOException;
import java.util.Arrays;
import com.flagstone.transform.coder.Coder;
import com.flagstone.transform.coder.Context;
import com.flagstone.transform.coder.SWFDecoder;
import com.flagstone.transform.coder.SWFEncoder;
/**
* DoABC is used to define scripts containing Actionscript 3.0 byte-codes.
*
* <p>
* Execution of the script may be deferred until it is explicitly called using
* the assigned name.
* </p>
*/
public final class DoABC implements MovieTag {
/** Format string used in toString() method. */
private static final String FORMAT = "DoABC: { name=%s; deferred=%d;"
+ " actions=byte<%d> ...}";
/** The name of the script. */
private String name;
/** Is loading deferred until the script is called. */
private int deferred;
/** The encoded actionscript 3 bytes codes. */
private byte[] data;
/** The length of the object, minus the header, when it is encoded. */
private transient int length;
/**
* Creates and initialises an DoABC using values encoded in the Flash
* binary format.
*
* @param coder
* an SWFDecoder object that contains the encoded Flash data.
*
* @throws IOException
* if an error occurs while decoding the data.
*/
public DoABC(final SWFDecoder coder) throws IOException {
length = coder.readUnsignedShort() & Coder.LENGTH_FIELD;
if (length == Coder.IS_EXTENDED) {
length = coder.readInt();
}
coder.mark();
deferred = coder.readInt();
name = coder.readString();
data = coder.readBytes(new byte[length - coder.bytesRead()]);
coder.check(length);
coder.unmark();
}
/**
* Creates a DoABC object with the name and compiled Actionscript 3.0
* byte-codes.
*
* @param scriptName
* the name used to identify the script.
* @param defer
* whether execution of the script is deferred.
* @param script
* the compiled Actionscript 3.0 byte-codes.
*/
public DoABC(final String scriptName, final boolean defer,
final byte[] script) {
setName(scriptName);
setDeferred(defer);
setData(script);
}
/**
* Creates a DoABC initialised with a copy of the data from another object.
*
* @param object
* a DoABC object used to initialize this one.
*/
public DoABC(final DoABC object) {
name = object.name;
deferred = object.deferred;
data = object.data;
}
/**
* Get the name of the script.
*
* @return the name used to call the script.
*/
public String getName() {
return name;
}
/**
* Sets the name of the script.
*
* @param aString
* the name assigned to the script so it can be referred to. Must
* not be null or an empty string.
*/
public void setName(final String aString) {
if (aString == null || aString.length() == 0) {
throw new IllegalArgumentException();
}
name = aString;
}
/**
* Is loading of the script deferred until it is called.
*
* @return true if loading of the script is deferred, false if it is loaded
* immediately.
*/
public boolean isDeferred() {
return (deferred & 1) != 0;
}
/**
* Sets whether execution of the script is deferred.
*
* @param defer
* execution of the script is deferred (true) or executed
* immediately (false).
*/
public void setDeferred(final boolean defer) {
if (defer) {
deferred = 1;
} else {
deferred = 0;
}
}
/**
* Get a copy of the array containing the Actionscript byte-codes.
*
* @return a copy of the encoded actionscript.
*/
public byte[] getData() {
return Arrays.copyOf(data, data.length);
}
/**
* Sets the script containing compiled Actionscript 3.0 byte-codes.
*
* @param bytes
* a list of byte-codes. Must not be null.
*/
public void setData(final byte[] bytes) {
if (bytes == null) {
throw new IllegalArgumentException();
}
data = Arrays.copyOf(bytes, bytes.length);
}
/** {@inheritDoc} */
public DoABC copy() {
return new DoABC(this);
}
@Override
public String toString() {
return String.format(FORMAT, name, deferred, data.length);
}
/** {@inheritDoc} */
public int prepareToEncode(final Context context) {
// CHECKSTYLE:OFF
length = 4 + context.strlen(name) + data.length;
return (length > Coder.HEADER_LIMIT ? Coder.LONG_HEADER
: Coder.SHORT_HEADER) + length;
// CHECKSTYLE:ON
}
/** {@inheritDoc} */
public void encode(final SWFEncoder coder, final Context context)
throws IOException {
if (length > Coder.HEADER_LIMIT) {
coder.writeShort((MovieTypes.DO_ABC
<< Coder.LENGTH_FIELD_SIZE) | Coder.IS_EXTENDED);
coder.writeInt(length);
} else {
coder.writeShort((MovieTypes.DO_ABC
<< Coder.LENGTH_FIELD_SIZE) | length);
}
if (Constants.DEBUG) {
coder.mark();
}
coder.writeInt(deferred);
coder.writeString(name);
coder.writeBytes(data);
if (Constants.DEBUG) {
coder.check(length);
coder.unmark();
}
}
}