/*
* Import.java
* Transform
*
* Copyright (c) 2001-2010 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.LinkedHashMap;
import java.util.Map;
import com.flagstone.transform.coder.Coder;
import com.flagstone.transform.coder.Context;
import com.flagstone.transform.coder.SWFDecoder;
import com.flagstone.transform.coder.SWFEncoder;
import com.flagstone.transform.exception.IllegalArgumentRangeException;
/**
* Import is used to import shapes and other objects from another Flash file
* referenced by a URL.
*
* <p>
* To provide a degree of security the Flash Player will only import files that
* originate from the same domain as the file that it is currently playing. For
* example if the Flash file being shown was loaded from
* www.mydomain.com/flash.swf then the file contains the exported objects must
* reside somewhere at www.mydomain.com. This prevents a malicious Flash file
* from loading files from an unknown third party.
* </p>
*
* <p>
* Since the identifier for an object is only unique within a given Flash file,
* imported objects are referenced by a name assigned when the object is
* exported.
* </p>
*
* @see Export
*/
public final class Import implements MovieTag {
/** Format string used in toString() method. */
private static final String FORMAT = "Import: { url=%s; objects=%s}";
/** The URL referencing the file to import. */
private String url;
/** The table of mapping named objects to unique identifiers. */
private Map<Integer, String> objects;
/** The length of the object, minus the header, when it is encoded. */
private transient int length;
/**
* Creates and initialises an Import object 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 Import(final SWFDecoder coder) throws IOException {
length = coder.readUnsignedShort() & Coder.LENGTH_FIELD;
if (length == Coder.IS_EXTENDED) {
length = coder.readInt();
}
coder.mark();
url = coder.readString();
final int count = coder.readUnsignedShort();
objects = new LinkedHashMap<Integer, String>(count);
for (int i = 0; i < count; i++) {
objects.put(coder.readUnsignedShort(), coder.readString());
}
coder.check(length);
coder.unmark();
}
/**
* Creates an Import object with an empty table.
*/
public Import() {
objects = new LinkedHashMap<Integer, String>();
}
/**
* Creates a Import object that imports an object from the specified file.
*
* @param aUrl
* the URL referencing the file to be imported.
*
* @param map
* the table to add the identifier-name pairs of the objects that
* will be imported.
*/
public Import(final String aUrl, final Map<Integer, String> map) {
setUrl(aUrl);
objects = map;
}
/**
* Creates and initialises an Import object using the values copied
* from another Import object.
*
* @param object
* an Import object from which the values will be
* copied.
*/
public Import(final Import object) {
url = object.url;
objects = new LinkedHashMap<Integer, String>(object.objects);
}
/**
* Adds the identifier and name to the list of objects to be imported.
*
* @param uid
* the identifier of the object to be imported. Must be in the
* range 1..65535.
* @param aString
* the name of the imported object to allow it to be referenced.
* Must not be null or an empty string.
* @return this object.
*/
public Import add(final int uid, final String aString) {
if ((uid < 1) || (uid > Coder.USHORT_MAX)) {
throw new IllegalArgumentRangeException(
1, Coder.USHORT_MAX, uid);
}
if (aString == null || aString.length() == 0) {
throw new IllegalArgumentException();
}
objects.put(uid, aString);
return this;
}
/**
* Get the URL of the file containing the object to be imported. Limited
* security is provided by requiring that the URL must be in the same domain
* or sub-domain as the URL of the movie which contains this object.
*
* @return the URL used to import the objects.
*/
public String getUrl() {
return url;
}
/**
* Get the table of objects to be imported.
*
* @return the mapping of the names of the imported objects to unique
* identifiers in this movie.
*/
public Map<Integer, String> getObjects() {
return objects;
}
/**
* Sets the URL of the file containing the imported objects. The URL must be
* in the same sub-domain and relative to the URL of the file containing the
* Import object.
*
* @param aString
* a URL relative to the URL of the file containing the Import
* object. Must not be null or an empty string.
*/
public void setUrl(final String aString) {
if (aString == null || aString.length() == 0) {
throw new IllegalArgumentException();
}
url = aString;
}
/**
* Sets the table of objects to be imported.
*
* @param aTable
* the table of objects being imported. Must not be null.
*/
public void setObjects(final Map<Integer, String> aTable) {
objects = aTable;
}
/** {@inheritDoc} */
public Import copy() {
return new Import(this);
}
/** {@inheritDoc} */
@Override
public String toString() {
return String.format(FORMAT, url, objects);
}
/** {@inheritDoc} */
public int prepareToEncode(final Context context) {
length = 2 + context.strlen(url);
for (final Integer identifier : objects.keySet()) {
length += 2 + context.strlen(objects.get(identifier));
}
return (length > Coder.HEADER_LIMIT ? Coder.LONG_HEADER
: Coder.SHORT_HEADER) + length;
}
/** {@inheritDoc} */
public void encode(final SWFEncoder coder, final Context context)
throws IOException {
if (length > Coder.HEADER_LIMIT) {
coder.writeShort((MovieTypes.IMPORT
<< Coder.LENGTH_FIELD_SIZE) | Coder.IS_EXTENDED);
coder.writeInt(length);
} else {
coder.writeShort((MovieTypes.IMPORT
<< Coder.LENGTH_FIELD_SIZE) | length);
}
coder.writeString(url);
coder.writeShort(objects.size());
for (final Integer identifier : objects.keySet()) {
coder.writeShort(identifier.intValue());
coder.writeString(objects.get(identifier));
}
}
}