jurt/com/sun/star/lib/uno/bridges/java_remote/ProxyFactory.java

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  30
  31 package com.sun.star.lib.uno.bridges.java_remote;
  32
  33 import com.sun.star.bridge.XBridge;
  34 import com.sun.star.lib.util.AsynchronousFinalizer;
  35 import com.sun.star.uno.IQueryInterface;
  36 import com.sun.star.uno.Type;
  37 import com.sun.star.uno.UnoRuntime;
  38 import java.lang.reflect.InvocationHandler;
  39 import java.lang.reflect.Method;
  40 import java.lang.reflect.Proxy;
  41
  42 /**
  43  * A factory for proxies specific to the <code>java_remote_bridge</code>.
  44  *
  45  * <p>Eventually, this class should be united with all other proxy classes
  46  * specific to certain bridges (for example, the JNI bridge), resulting in a
  47  * generic proxy class.</p>
  48  */
  49 final class ProxyFactory {
  50     public ProxyFactory(RequestHandler requestHandler, XBridge bridge) {
  51         this.requestHandler = requestHandler;
  52         this.bridge = bridge;
  53     }
  54
  55     public Object create(String oid, Type type) {
  56         return Proxy.newProxyInstance(
  57             getClass().getClassLoader(),
  58             new Class[] { com.sun.star.lib.uno.Proxy.class,
  59                           IQueryInterface.class, type.getZClass() },
  60             new Handler(oid, type));
  61     }
  62
  63     public boolean isProxy(Object obj) {
  64         if (Proxy.isProxyClass(obj.getClass())) {
  65             InvocationHandler h = Proxy.getInvocationHandler(obj);
  66             return h instanceof Handler && ((Handler) h).matches(this);
  67         } else {
  68             return false;
  69         }
  70     }
  71
  72     public static XBridge getBridge(Object obj) {
  73         if (Proxy.isProxyClass(obj.getClass())) {
  74             InvocationHandler h = Proxy.getInvocationHandler(obj);
  75             if (h instanceof Handler) {
  76                 return ((Handler) h).getBridge();
  77             }
  78         }
  79         return null;
  80     }
  81
  82     static int getDebugCount() {
  83         synchronized (debugCountLock) {
  84             return debugCount;
  85         }
  86     }
  87
  88     private static void incrementDebugCount() {
  89         synchronized (debugCountLock) {
  90             ++debugCount;
  91         }
  92     }
  93
  94     private static void decrementDebugCount() {
  95         synchronized (debugCountLock) {
  96             --debugCount;
  97         }
  98     }
  99
 100     private final class Handler implements InvocationHandler {
 101         public Handler(String oid, Type type) {
 102             this.oid = oid;
 103             this.type = type;
 104             incrementDebugCount();
 105         }
 106
 107         public boolean matches(ProxyFactory factory) {
 108             return ProxyFactory.this == factory;
 109         }
 110
 111         public XBridge getBridge() {
 112             return bridge;
 113         }
 114
 115         public Object invoke(Object proxy, Method method, Object[] args)
 116             throws Throwable
 117         {
 118             if (method.equals(METHOD_EQUALS) || method.equals(METHOD_IS_SAME)) {
 119                 return new Boolean(
 120                     args[0] != null
 121                     && oid.equals(UnoRuntime.generateOid(args[0])));
 122             } else if (method.equals(METHOD_HASH_CODE)) {
 123                 return new Integer(oid.hashCode());
 124             } else if (method.equals(METHOD_TO_STRING)) {
 125                 return "[Proxy:" + System.identityHashCode(proxy) + "," + oid
 126                     + "," + type + "]";
 127             } else if (method.equals(METHOD_QUERY_INTERFACE)) {
 128                 // See the comment in java_remote_bridge.mapInterfaceTo for one
 129                 // reason why this implementation must not satisfy a request for
 130                 // a super-interface with a proxy itself:
 131                 return args[0].equals(type) ? proxy
 132                     : request("queryInterface", args);
 133             } else if (method.equals(METHOD_GET_OID)) {
 134                 return oid;
 135             } else {
 136                 return request(method.getName(), args);
 137             }
 138         }
 139
 140         protected void finalize() {
 141             AsynchronousFinalizer.add(new AsynchronousFinalizer.Job() {
 142                     public void run() throws Throwable {
 143                         try {
 144                             request("release", null);
 145                         } finally {
 146                             decrementDebugCount();
 147                         }
 148                     }
 149                 });
 150         }
 151
 152         private Object request(String operation, Object[] args) throws Throwable
 153         {
 154             return requestHandler.sendRequest(oid, type, operation, args);
 155         }
 156
 157         private final String oid;
 158         private final Type type;
 159     }
 160
 161     private static final Method METHOD_EQUALS;
 162     private static final Method METHOD_HASH_CODE;
 163     private static final Method METHOD_TO_STRING;
 164     private static final Method METHOD_QUERY_INTERFACE;
 165     private static final Method METHOD_IS_SAME;
 166     private static final Method METHOD_GET_OID;
 167     static {
 168         try {
 169             METHOD_EQUALS = Object.class.getMethod(
 170                 "equals", new Class[] { Object.class });
 171             METHOD_HASH_CODE = Object.class.getMethod("hashCode", null);
 172             METHOD_TO_STRING = Object.class.getMethod("toString", null);
 173             METHOD_QUERY_INTERFACE = IQueryInterface.class.getMethod(
 174                 "queryInterface", new Class[] { Type.class });
 175             METHOD_IS_SAME = IQueryInterface.class.getMethod(
 176                 "isSame", new Class[] { Object.class });
 177             METHOD_GET_OID = IQueryInterface.class.getMethod("getOid", null);
 178         } catch (NoSuchMethodException e) {
 179             throw new ExceptionInInitializerError(e);
 180         }
 181     }
 182
 183     private static final Object debugCountLock = new Object();
 184     private static int debugCount = 0;
 185
 186     private final RequestHandler requestHandler;
 187     private final XBridge bridge;
 188 }