Review Request: CR 7100996 - (spec str) IndexOutOfBoundsException when using a StringBuffer from multiple threads

[Jim Gish]

Hopefully, this will address most, if not all of the suggestions made to 
date.

....Jim

diff -r f37afaa214e9 src/share/classes/java/lang/StringBuffer.java
--- a/src/share/classes/java/lang/StringBuffer.java    Mon Jun 25 
14:22:42 2012 -0400
+++ b/src/share/classes/java/lang/StringBuffer.java    Mon Jun 25 
15:30:57 2012 -0400
@@ -39,40 +39,38 @@
   * that is consistent with the order of the method calls made by each of
   * the individual threads involved.
   * <p>
- * The principal operations on a <code>StringBuffer</code> are the
- * <code>append</code> and <code>insert</code> methods, which are
+ * The principal operations on a {@code StringBuffer} are the
+ * {@code append} and {@code insert} methods, which are
   * overloaded so as to accept data of any type. Each effectively
   * converts a given datum to a string and then appends or inserts the
   * characters of that string to the string buffer. The
- * <code>append</code> method always adds these characters at the end
- * of the buffer; the <code>insert</code> method adds the characters at
+ * {@code append} method always adds these characters at the end
+ * of the buffer; the {@code insert} method adds the characters at
   * a specified point.
   * <p>
- * For example, if <code>z</code> refers to a string buffer object
- * whose current contents are "<code>start</code>", then
- * the method call <code>z.append("le")</code> would cause the string
- * buffer to contain "<code>startle</code>", whereas
- * <code>z.insert(4, "le")</code> would alter the string buffer to
- * contain "<code>starlet</code>".
+ * For example, if {@code z} refers to a string buffer object
+ * whose current contents are "{@code start}", then
+ * the method call {@code z.append("le")} would cause the string
+ * buffer to contain "{@code startle}", whereas
+ * {@code z.insert(4, "le")} would alter the string buffer to
+ * contain "{@code starlet}".
   * <p>
- * In general, if sb refers to an instance of a <code>StringBuffer</code>,
- * then <code>sb.append(x)</code> has the same effect as
- * <code>sb.insert(sb.length(), x)</code>.
+ * In general, if sb refers to an instance of a {@code StringBuffer},
+ * then {@code sb.append(x)} has the same effect as
+ * {@code sb.insert(sb.length(), x)}.
   * <p>
   * Whenever an operation occurs involving a source sequence (such as
- * appending or inserting from a source sequence) this class synchronizes
+ * appending or inserting from a source sequence), this class synchronizes
   * only on the string buffer performing the operation, not on the source.
- * <p>
- * Although {@code StringBuffer} is designed to be safe to use
- * concurrently from multiple threads, if the source data passed
- * to the constructor, i.e. {@code StringBuffer(source)}, or to the
- * {@code append(source)}, or {@code insert(source)} operations
- * is shared across threads, it must be ensured that the operations have
- * a consistent and unchanging view of the source data for the duration
- * of the operation.
+ * {@code StringBuffer} is designed to be safe to use
+ * concurrently from multiple threads, but if the source data passed
+ * to the constructor  or to the {@code append()}, or {@code insert()}
+ * operations is shared across threads, the calling code must be ensure
+ * that the operations have a consistent and unchanging view of the source
+ * data for the duration of the operation.
   * This could be satisfied by the caller holding a lock during the
- * operation's call, or because the source data is
- * immutable, or because the source data is not shared across threads.
+ * operation's call, or by the source data being
+ * immutable, or by the source data not being shared across threads.
   * <p>
   * Every string buffer has a capacity. As long as the length of the
   * character sequence contained in the string buffer does not exceed
@@ -112,8 +110,8 @@
       * the specified initial capacity.
       *
       * @param      capacity  the initial capacity.
-     * @exception  NegativeArraySizeException  if the <code>capacity</code>
-     *               argument is less than <code>0</code>.
+     * @exception  NegativeArraySizeException  if the {@code capacity}
+     *               argument is less than {@code 0}.
       */
      public StringBuffer(int capacity) {
          super(capacity);
@@ -122,10 +120,10 @@
      /**
       * Constructs a string buffer initialized to the contents of the
       * specified string. The initial capacity of the string buffer is
-     * <code>16</code> plus the length of the string argument.
+     * {@code 16} plus the length of the string argument.
       *
       * @param   str   the initial contents of the buffer.
-     * @exception NullPointerException if <code>str</code> is 
<code>null</code>
+     * @exception NullPointerException if {@code str} is {@code null}
       */
      public StringBuffer(String str) {
          super(str.length() + 16);
@@ -134,16 +132,16 @@

      /**
       * Constructs a string buffer that contains the same characters
-     * as the specified <code>CharSequence</code>. The initial capacity of
-     * the string buffer is <code>16</code> plus the length of the
-     * <code>CharSequence</code> argument.
+     * as the specified {@code CharSequence}. The initial capacity of
+     * the string buffer is {@code 16} plus the length of the
+     * {@code CharSequence} argument.
       * <p>
-     * If the length of the specified <code>CharSequence</code> is
+     * If the length of the specified {@code CharSequence} is
       * less than or equal to zero, then an empty buffer of capacity
-     * <code>16</code> is returned.
+     * {@code 16} is returned.
       *
       * @param      seq   the sequence to copy.
-     * @exception NullPointerException if <code>seq</code> is 
<code>null</code>
+     * @exception NullPointerException if {@code seq} is {@code null}
       * @since 1.5
       */
      public StringBuffer(CharSequence seq) {
@@ -264,10 +262,10 @@
       * the new character sequence is equal to the character at index 
<i>k</i>
       * in the old character sequence, if <i>k</i> is less than <i>n</i>;
       * otherwise, it is equal to the character at index <i>k-n</i> in the
-     * argument <code>sb</code>.
+     * argument {@code sb}.
       * <p>
-     * This method synchronizes on <code>this</code> (the destination)
-     * object but does not synchronize on the source (<code>sb</code>).
+     * This method synchronizes on {@code this} (the destination)
+     * object but does not synchronize on the source ({@code sb}).
       *
       * @param   sb   the <tt>StringBuffer</tt> to append.
       * @return  a reference to this object.
@@ -280,10 +278,10 @@


      /**
-     * Appends the specified <code>CharSequence</code> to this
+     * Appends the specified {@code CharSequence} to this
       * sequence.
       * <p>
-     * The characters of the <code>CharSequence</code> argument are 
appended,
+     * The characters of the {@code CharSequence} argument are appended,
       * in order, increasing the length of this sequence by the length 
of the
       * argument.
       *
@@ -291,12 +289,12 @@
       * invocation of this.append(s, 0, s.length());
       *
       * <p>This method synchronizes on this (the destination)
-     * object but does not synchronize on the source (<code>s</code>).
+     * object but does not synchronize on the source ({@code s}).
       *
-     * <p>If <code>s</code> is <code>null</code>, then the four characters
-     * <code>"null"</code> are appended.
+     * <p>If {@code s} is {@code null}, then the four characters
+     * {@code "null"} are appended.
       *
-     * @param   s the <code>CharSequence</code> to append.
+     * @param   s the {@code CharSequence} to append.
       * @return  a reference to this object.
       * @since 1.5
       */