[Javapathfinder-devel] javapathfinder/env/jvm/gov/nasa/jpf/jvm JPF_java_lang_StringBuffer.java,1.1.1.1,1.2

[pcm <pcm...@us...>]

Update of /cvsroot/javapathfinder/javapathfinder/env/jvm/gov/nasa/jpf/jvm
In directory sc8-pr-cvs1.sourceforge.net:/tmp/cvs-serv23195/env/jvm/gov/nasa/jpf/jvm

Modified Files:
	JPF_java_lang_StringBuffer.java 
Log Message:
Java 1.5 apparently has changed the java.lang.StringBuffer implementation
(the 'shared' hack is gone), so we have to do some evil version branching
in our native peer class


Index: JPF_java_lang_StringBuffer.java
===================================================================
RCS file: /cvsroot/javapathfinder/javapathfinder/env/jvm/gov/nasa/jpf/jvm/JPF_java_lang_StringBuffer.java,v
retrieving revision 1.1.1.1
retrieving revision 1.2
diff -u -d -r1.1.1.1 -r1.2
--- JPF_java_lang_StringBuffer.java	26 Apr 2005 19:43:27 -0000	1.1.1.1
+++ JPF_java_lang_StringBuffer.java	26 Aug 2005 21:30:28 -0000	1.2
@@ -23,8 +23,25 @@
 /**
  * MJI NativePeer class for java.lang.StringBuffer library abstraction
  */
-public class JPF_java_lang_StringBuffer
-{
+public class JPF_java_lang_StringBuffer {
+  
+  static boolean hasSharedField = false; // Java 1.4 has, 1.5 doesn't
+  
+  public static void $clinit (MJIEnv env, int clsObjRef) {
+    // apparently, Java 1.5 has changed the implementation of class
+    // StringBuffer so that it doesn't use the 'shared' state anymore
+    // (which was a performance hack to avoid copying the char array
+    // data when creating String objects from subsequently unmodified
+    // StringBuffers
+    // adding this little extra logic here also serves the purpose of
+    // avoiding a native ObjectStreamClass method which is called during
+    // the static StringBuffer init
+    ClassInfo ci = env.getClassInfo();
+    if (ci.getInstanceField("shared") != null) {
+      hasSharedField = true;
+    }
+  }
+  
   static int appendString (MJIEnv env, int objref, String s) {
     int slen = s.length();
     int aref = env.getReferenceField(objref, "value");
@@ -52,7 +69,9 @@
       env.setReferenceField(objref, "value", arefNew);
     }
     
-    env.setBooleanField(objref, "shared", false);
+    if (hasSharedField) {
+      env.setBooleanField(objref, "shared", false);
+    }
     env.setIntField(objref, "count", n);
     
     return objref;
@@ -128,7 +147,9 @@
       env.setReferenceField(objref, "value", arefNew);
     }
     
-    env.setBooleanField(objref, "shared", false);
+    if (hasSharedField) {
+      env.setBooleanField(objref, "shared", false);
+    }
     env.setIntField(objref, "count", n);
     
     return objref;