re PR libgcj/12350 (StringBuffer.substring handles shared flag incorrected.)

2003-09-21  Ralph Loader  <suckfish@ihug.co.nz>

        PR java/12350:
        * java/lang/StringBuffer.java (substring): Fix handling of shared
        flag.

2003-09-21  Ralph Loader  <suckfish@ihug.co.nz>

        PR java/12350
        * libjava.lang/PR12350.java: New file.
        * libjava.lang/PR12350.out: New file.

From-SVN: r71651

libjava/ChangeLog

+2003-09-21  Ralph Loader  <suckfish@ihug.co.nz>
+
+	PR java/12350:
+	* java/lang/StringBuffer.java (substring): Fix handling of shared flag.
+
 2003-09-22  Michael Koch  <konqueror@gmx.de>
 
 	* jni.cc (_Jv_LookupJNIMethod): Remove workaround that should hide a

libjava/java/lang/StringBuffer.java

@@ -564,8 +564,9 @@ public final class StringBuffer implements Serializable, CharSequence
       throw new StringIndexOutOfBoundsException();
     if (len == 0)
       return "";
-    // Share the char[] unless 3/4 empty.
-    shared = (len << 2) >= value.length;
+    // Share unless substring is smaller than 1/4 of the buffer.
+    if ((len << 2) >= value.length)
+      shared = true;
     // Package constructor avoids an array copy.
     return new String(value, beginIndex, len, shared);
   }

libjava/testsuite/ChangeLog

+2003-09-21  Ralph Loader  <suckfish@ihug.co.nz>
+
+	PR java/12350
+	* libjava.lang/PR12350.java: New file.
+	* libjava.lang/PR12350.out: New file.
+
 2003-09-17  Ranjit Mathew  <rmathew@hotmail.com>
 
 	PR java/9577

libjava/testsuite/libjava.lang/PR12350.java

+public class PR12350
+{
+    static public void main (String[] ignored) throws Throwable
+    {
+	StringBuffer b = new StringBuffer ("Good string.  More than 16 chars.");
+
+	// Should cause sharing.
+	String s = b.toString();
+
+	// Take a char by char unshared copy of s.
+	String t = new String (s.toCharArray());
+
+	b.substring (0, 4);	// BUG: Clears shared flag.
+	b.replace (0, 4, "Bad "); // Modifies shared data.
+
+	System.out.println (s);
+	assert s.equals (t);
+    }
+
+}

libjava/testsuite/libjava.lang/PR12350.out

+Good string.  More than 16 chars.