| /* |
| * Copyright (c) 2000, 2012, Oracle and/or its affiliates. All rights reserved. |
| * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. |
| * |
| * This code is free software; you can redistribute it and/or modify it |
| * under the terms of the GNU General Public License version 2 only, as |
| * published by the Free Software Foundation. Oracle designates this |
| * particular file as subject to the "Classpath" exception as provided |
| * by Oracle in the LICENSE file that accompanied this code. |
| * |
| * This code 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 General Public License |
| * version 2 for more details (a copy is included in the LICENSE file that |
| * accompanied this code). |
| * |
| * You should have received a copy of the GNU General Public License version |
| * 2 along with this work; if not, write to the Free Software Foundation, |
| * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. |
| * |
| * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA |
| * or visit www.oracle.com if you need additional information or have any |
| * questions. |
| */ |
| package java.beans; |
| |
| import com.sun.beans.decoder.DocumentHandler; |
| |
| import java.io.Closeable; |
| import java.io.InputStream; |
| import java.io.IOException; |
| import java.security.AccessControlContext; |
| import java.security.AccessController; |
| import java.security.PrivilegedAction; |
| |
| import org.xml.sax.InputSource; |
| import org.xml.sax.helpers.DefaultHandler; |
| |
| /** |
| * The {@code XMLDecoder} class is used to read XML documents |
| * created using the {@code XMLEncoder} and is used just like |
| * the {@code ObjectInputStream}. For example, one can use |
| * the following fragment to read the first object defined |
| * in an XML document written by the {@code XMLEncoder} |
| * class: |
| * <pre> |
| * XMLDecoder d = new XMLDecoder( |
| * new BufferedInputStream( |
| * new FileInputStream("Test.xml"))); |
| * Object result = d.readObject(); |
| * d.close(); |
| * </pre> |
| * |
| *<p> |
| * For more information you might also want to check out |
| * <a href="http://www.oracle.com/technetwork/java/persistence3-139471.html"> |
| * Long Term Persistence of JavaBeans Components: XML Schema</a>, |
| * an article in <em>The Swing Connection.</em> |
| * @see XMLEncoder |
| * @see java.io.ObjectInputStream |
| * |
| * @since 1.4 |
| * |
| * @author Philip Milne |
| */ |
| public class XMLDecoder implements AutoCloseable { |
| private final AccessControlContext acc = AccessController.getContext(); |
| private final DocumentHandler handler = new DocumentHandler(); |
| private final InputSource input; |
| private Object owner; |
| private Object[] array; |
| private int index; |
| |
| /** |
| * Creates a new input stream for reading archives |
| * created by the {@code XMLEncoder} class. |
| * |
| * @param in The underlying stream. |
| * |
| * @see XMLEncoder#XMLEncoder(java.io.OutputStream) |
| */ |
| public XMLDecoder(InputStream in) { |
| this(in, null); |
| } |
| |
| /** |
| * Creates a new input stream for reading archives |
| * created by the {@code XMLEncoder} class. |
| * |
| * @param in The underlying stream. |
| * @param owner The owner of this stream. |
| * |
| */ |
| public XMLDecoder(InputStream in, Object owner) { |
| this(in, owner, null); |
| } |
| |
| /** |
| * Creates a new input stream for reading archives |
| * created by the {@code XMLEncoder} class. |
| * |
| * @param in the underlying stream. |
| * @param owner the owner of this stream. |
| * @param exceptionListener the exception handler for the stream; |
| * if {@code null} the default exception listener will be used. |
| */ |
| public XMLDecoder(InputStream in, Object owner, ExceptionListener exceptionListener) { |
| this(in, owner, exceptionListener, null); |
| } |
| |
| /** |
| * Creates a new input stream for reading archives |
| * created by the {@code XMLEncoder} class. |
| * |
| * @param in the underlying stream. {@code null} may be passed without |
| * error, though the resulting XMLDecoder will be useless |
| * @param owner the owner of this stream. {@code null} is a legal |
| * value |
| * @param exceptionListener the exception handler for the stream, or |
| * {@code null} to use the default |
| * @param cl the class loader used for instantiating objects. |
| * {@code null} indicates that the default class loader should |
| * be used |
| * @since 1.5 |
| */ |
| public XMLDecoder(InputStream in, Object owner, |
| ExceptionListener exceptionListener, ClassLoader cl) { |
| this(new InputSource(in), owner, exceptionListener, cl); |
| } |
| |
| |
| /** |
| * Creates a new decoder to parse XML archives |
| * created by the {@code XMLEncoder} class. |
| * If the input source {@code is} is {@code null}, |
| * no exception is thrown and no parsing is performed. |
| * This behavior is similar to behavior of other constructors |
| * that use {@code InputStream} as a parameter. |
| * |
| * @param is the input source to parse |
| * |
| * @since 1.7 |
| */ |
| public XMLDecoder(InputSource is) { |
| this(is, null, null, null); |
| } |
| |
| /** |
| * Creates a new decoder to parse XML archives |
| * created by the {@code XMLEncoder} class. |
| * |
| * @param is the input source to parse |
| * @param owner the owner of this decoder |
| * @param el the exception handler for the parser, |
| * or {@code null} to use the default exception handler |
| * @param cl the class loader used for instantiating objects, |
| * or {@code null} to use the default class loader |
| * |
| * @since 1.7 |
| */ |
| private XMLDecoder(InputSource is, Object owner, ExceptionListener el, ClassLoader cl) { |
| this.input = is; |
| this.owner = owner; |
| setExceptionListener(el); |
| this.handler.setClassLoader(cl); |
| this.handler.setOwner(this); |
| } |
| |
| /** |
| * This method closes the input stream associated |
| * with this stream. |
| */ |
| public void close() { |
| if (parsingComplete()) { |
| close(this.input.getCharacterStream()); |
| close(this.input.getByteStream()); |
| } |
| } |
| |
| private void close(Closeable in) { |
| if (in != null) { |
| try { |
| in.close(); |
| } |
| catch (IOException e) { |
| getExceptionListener().exceptionThrown(e); |
| } |
| } |
| } |
| |
| private boolean parsingComplete() { |
| if (this.input == null) { |
| return false; |
| } |
| if (this.array == null) { |
| if ((this.acc == null) && (null != System.getSecurityManager())) { |
| throw new SecurityException("AccessControlContext is not set"); |
| } |
| AccessController.doPrivileged(new PrivilegedAction<Void>() { |
| public Void run() { |
| XMLDecoder.this.handler.parse(XMLDecoder.this.input); |
| return null; |
| } |
| }, this.acc); |
| this.array = this.handler.getObjects(); |
| } |
| return true; |
| } |
| |
| /** |
| * Sets the exception handler for this stream to {@code exceptionListener}. |
| * The exception handler is notified when this stream catches recoverable |
| * exceptions. |
| * |
| * @param exceptionListener The exception handler for this stream; |
| * if {@code null} the default exception listener will be used. |
| * |
| * @see #getExceptionListener |
| */ |
| public void setExceptionListener(ExceptionListener exceptionListener) { |
| if (exceptionListener == null) { |
| exceptionListener = Statement.defaultExceptionListener; |
| } |
| this.handler.setExceptionListener(exceptionListener); |
| } |
| |
| /** |
| * Gets the exception handler for this stream. |
| * |
| * @return The exception handler for this stream. |
| * Will return the default exception listener if this has not explicitly been set. |
| * |
| * @see #setExceptionListener |
| */ |
| public ExceptionListener getExceptionListener() { |
| return this.handler.getExceptionListener(); |
| } |
| |
| /** |
| * Reads the next object from the underlying input stream. |
| * |
| * @return the next object read |
| * |
| * @throws ArrayIndexOutOfBoundsException if the stream contains no objects |
| * (or no more objects) |
| * |
| * @see XMLEncoder#writeObject |
| */ |
| public Object readObject() { |
| return (parsingComplete()) |
| ? this.array[this.index++] |
| : null; |
| } |
| |
| /** |
| * Sets the owner of this decoder to {@code owner}. |
| * |
| * @param owner The owner of this decoder. |
| * |
| * @see #getOwner |
| */ |
| public void setOwner(Object owner) { |
| this.owner = owner; |
| } |
| |
| /** |
| * Gets the owner of this decoder. |
| * |
| * @return The owner of this decoder. |
| * |
| * @see #setOwner |
| */ |
| public Object getOwner() { |
| return owner; |
| } |
| |
| /** |
| * Creates a new handler for SAX parser |
| * that can be used to parse embedded XML archives |
| * created by the {@code XMLEncoder} class. |
| * |
| * The {@code owner} should be used if parsed XML document contains |
| * the method call within context of the <java> element. |
| * The {@code null} value may cause illegal parsing in such case. |
| * The same problem may occur, if the {@code owner} class |
| * does not contain expected method to call. See details <a |
| * href="http://www.oracle.com/technetwork/java/persistence3-139471.html"> |
| * here</a>. |
| * |
| * @param owner the owner of the default handler |
| * that can be used as a value of <java> element |
| * @param el the exception handler for the parser, |
| * or {@code null} to use the default exception handler |
| * @param cl the class loader used for instantiating objects, |
| * or {@code null} to use the default class loader |
| * @return an instance of {@code DefaultHandler} for SAX parser |
| * |
| * @since 1.7 |
| */ |
| public static DefaultHandler createHandler(Object owner, ExceptionListener el, ClassLoader cl) { |
| DocumentHandler handler = new DocumentHandler(); |
| handler.setOwner(owner); |
| handler.setExceptionListener(el); |
| handler.setClassLoader(cl); |
| return handler; |
| } |
| } |