From 9fee0ec4ca0c5b7a334cc29dbb58e76c7a4c736e Mon Sep 17 00:00:00 2001 From: Michiel Van Der Kolk Date: Mon, 11 Jul 2005 15:42:37 +0000 Subject: Songdb java version, source. only 1.5 compatible git-svn-id: svn://svn.rockbox.org/rockbox/trunk@7101 a1c6a512-1295-4272-9138-f99709370657 --- songdbj/javazoom/jl/decoder/JavaLayerUtils.java | 207 ++++++++++++++++++++++++ 1 file changed, 207 insertions(+) create mode 100644 songdbj/javazoom/jl/decoder/JavaLayerUtils.java (limited to 'songdbj/javazoom/jl/decoder/JavaLayerUtils.java') diff --git a/songdbj/javazoom/jl/decoder/JavaLayerUtils.java b/songdbj/javazoom/jl/decoder/JavaLayerUtils.java new file mode 100644 index 0000000..c9ce383 --- /dev/null +++ b/songdbj/javazoom/jl/decoder/JavaLayerUtils.java @@ -0,0 +1,207 @@ +/* + * 11/19/04 1.0 moved to LGPL. + * 12/12/99 Initial version. mdm@techie.com + *----------------------------------------------------------------------- + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU Library General Public License as published + * by the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * This program 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 Library General Public License for more details. + * + * You should have received a copy of the GNU Library General Public + * License along with this program; if not, write to the Free Software + * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. + *---------------------------------------------------------------------- + */ + +package javazoom.jl.decoder; + +import java.io.IOException; +import java.io.InputStream; +import java.io.InvalidClassException; +import java.io.InvalidObjectException; +import java.io.ObjectInputStream; +import java.io.ObjectOutputStream; +import java.io.OutputStream; +import java.lang.reflect.Array; + +/** + * The JavaLayerUtils class is not strictly part of the JavaLayer API. + * It serves to provide useful methods and system-wide hooks. + * + * @author MDM + */ +public class JavaLayerUtils +{ + static private JavaLayerHook hook = null; + + /** + * Deserializes the object contained in the given input stream. + * @param in The input stream to deserialize an object from. + * @param cls The expected class of the deserialized object. + */ + static public Object deserialize(InputStream in, Class cls) + throws IOException + { + if (cls==null) + throw new NullPointerException("cls"); + + Object obj = deserialize(in, cls); + if (!cls.isInstance(obj)) + { + throw new InvalidObjectException("type of deserialized instance not of required class."); + } + + return obj; + } + + /** + * Deserializes an object from the given InputStream. + * The deserialization is delegated to an + * ObjectInputStream instance. + * + * @param in The InputStream to deserialize an object + * from. + * + * @return The object deserialized from the stream. + * @exception IOException is thrown if there was a problem reading + * the underlying stream, or an object could not be deserialized + * from the stream. + * + * @see java.io.ObjectInputStream + */ + static public Object deserialize(InputStream in) + throws IOException + { + if (in==null) + throw new NullPointerException("in"); + + ObjectInputStream objIn = new ObjectInputStream(in); + + Object obj; + + try + { + obj = objIn.readObject(); + } + catch (ClassNotFoundException ex) + { + throw new InvalidClassException(ex.toString()); + } + + return obj; + } + + /** + * Deserializes an array from a given InputStream. + * + * @param in The InputStream to + * deserialize an object from. + * + * @param elemType The class denoting the type of the array + * elements. + * @param length The expected length of the array, or -1 if + * any length is expected. + */ + static public Object deserializeArray(InputStream in, Class elemType, int length) + throws IOException + { + if (elemType==null) + throw new NullPointerException("elemType"); + + if (length<-1) + throw new IllegalArgumentException("length"); + + Object obj = deserialize(in); + + Class cls = obj.getClass(); + + + if (!cls.isArray()) + throw new InvalidObjectException("object is not an array"); + + Class arrayElemType = cls.getComponentType(); + if (arrayElemType!=elemType) + throw new InvalidObjectException("unexpected array component type"); + + if (length != -1) + { + int arrayLength = Array.getLength(obj); + if (arrayLength!=length) + throw new InvalidObjectException("array length mismatch"); + } + + return obj; + } + + static public Object deserializeArrayResource(String name, Class elemType, int length) + throws IOException + { + InputStream str = getResourceAsStream(name); + if (str==null) + throw new IOException("unable to load resource '"+name+"'"); + + Object obj = deserializeArray(str, elemType, length); + + return obj; + } + + static public void serialize(OutputStream out, Object obj) + throws IOException + { + if (out==null) + throw new NullPointerException("out"); + + if (obj==null) + throw new NullPointerException("obj"); + + ObjectOutputStream objOut = new ObjectOutputStream(out); + objOut.writeObject(obj); + + } + + /** + * Sets the system-wide JavaLayer hook. + */ + static synchronized public void setHook(JavaLayerHook hook0) + { + hook = hook0; + } + + static synchronized public JavaLayerHook getHook() + { + return hook; + } + + /** + * Retrieves an InputStream for a named resource. + * + * @param name The name of the resource. This must be a simple + * name, and not a qualified package name. + * + * @return The InputStream for the named resource, or null if + * the resource has not been found. If a hook has been + * provided, its getResourceAsStream() method is called + * to retrieve the resource. + */ + static synchronized public InputStream getResourceAsStream(String name) + { + InputStream is = null; + + if (hook!=null) + { + is = hook.getResourceAsStream(name); + } + else + { + Class cls = JavaLayerUtils.class; + is = cls.getResourceAsStream(name); + } + + return is; + } +} -- cgit v1.1