src/share/classes/java/io/ObjectOutputStream.java

@@ -33,11 +33,10 @@
 import java.util.Arrays;
 import java.util.List;
 import java.util.concurrent.ConcurrentHashMap;
 import java.util.concurrent.ConcurrentMap;
 import static java.io.ObjectStreamClass.processQueue;
-import java.io.SerialCallbackContext;
 import sun.reflect.misc.ReflectUtil;
 
 /**
  * An ObjectOutputStream writes primitive data types and graphs of Java objects
  * to an OutputStream.  The objects can be read (reconstituted) using an

@@ -456,11 +455,11 @@
         if (curPut == null) {
             SerialCallbackContext ctx = curContext;
             if (ctx == null) {
                 throw new NotActiveException("not in call to writeObject");
             }
-            Object curObj = ctx.getObj();
+            ctx.checkAndSetUsed();
             ObjectStreamClass curDesc = ctx.getDesc();
             curPut = new PutFieldImpl(curDesc);
         }
         return curPut;
     }

@@ -1525,18 +1524,22 @@
         }
 
         desc.checkDefaultSerialize();
 
         int primDataSize = desc.getPrimDataSize();
+        if (primDataSize > 0) {
         if (primVals == null || primVals.length < primDataSize) {
             primVals = new byte[primDataSize];
         }
         desc.getPrimFieldValues(obj, primVals);
         bout.write(primVals, 0, primDataSize, false);
+        }
 
+        int numObjFields = desc.getNumObjFields();
+        if (numObjFields > 0) {
         ObjectStreamField[] fields = desc.getFields(false);
-        Object[] objVals = new Object[desc.getNumObjFields()];
+            Object[] objVals = new Object[numObjFields];
         int numPrimFields = fields.length - objVals.length;
         desc.getObjFieldValues(obj, objVals);
         for (int i = 0; i < objVals.length; i++) {
             if (extendedDebugInfo) {
                 debugInfoStack.push(

@@ -1552,10 +1555,11 @@
                     debugInfoStack.pop();
                 }
             }
         }
     }
+    }
 
     /**
      * Attempts to write to stream fatal IOException that has caused
      * serialization to abort.
      */

@@ -2462,11 +2466,13 @@
          */
         public String toString() {
             StringBuilder buffer = new StringBuilder();
             if (!stack.isEmpty()) {
                 for(int i = stack.size(); i > 0; i-- ) {
-                    buffer.append(stack.get(i-1) + ((i != 1) ? "\n" : ""));
+                    buffer.append(stack.get(i - 1));
+                    if (i != 1)
+                        buffer.append('\n');
                 }
             }
             return buffer.toString();
         }
     }