/* * 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. *---------------------------------------------------------------------- */ //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) static public Object deserialize(InputStream in) throws IOException { // if (cls==null) // throw new NullPointerException("cls"); // Object obj = deserialize(in, cls); Object obj = deserialize(in); // 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"); //TODO : need to enable after having objectinputstream /* ObjectInputStream objIn = new ObjectInputStream(in); Object obj; try { obj = objIn.readObject(); } catch (ClassNotFoundException ex) { throw new InvalidClassException(ex.toString()); } return obj; */ return null; } /** * 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, int length) throws IOException { if (length<-1) throw new IllegalArgumentException("length"); Object obj = deserialize(in); return obj; } // 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); // // //SSJava will never throw exceptions as it is so this code is meaningless // /* // 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) static public Object deserializeArrayResource(String name, 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); Object obj = deserializeArray(str, length); return obj; } static public void serialize(OutputStream out, Object obj) throws IOException { //TODO : need to enable after having objectinputstream // 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); } //TODO java reflection // else // { // Class cls = JavaLayerUtils.class; // is = cls.getResourceAsStream(name); // } return is; } }