8300773: Address the inconsistency between the constant array and poo…

…l size

Backport-of: a34f2d3728c077d1dbdfa313f1bf29629fbc32f6

src/java.xml/share/classes/com/sun/org/apache/bcel/internal/classfile/ConstantPool.java

@@ -37,7 +37,7 @@
 
  * @see     Constant
  * @see     com.sun.org.apache.bcel.internal.generic.ConstantPoolGen
- * @LastModified: May 2022
+ * @LastModified: June 2022
  */
 public class ConstantPool implements Cloneable, Node {
 
@@ -228,8 +228,8 @@ public void dump( final DataOutputStream file ) throws IOException {
          * This is a redundant measure as the ConstantPoolGen should have already
          * reported an error back in the situation.
         */
-        int size = constantPool.length < ConstantPoolGen.CONSTANT_POOL_SIZE - 1 ?
-                constantPool.length : ConstantPoolGen.CONSTANT_POOL_SIZE - 1;
+        int size = constantPool.length < ConstantPoolGen.CONSTANT_POOL_SIZE ?
+                constantPool.length : ConstantPoolGen.CONSTANT_POOL_SIZE;
 
         file.writeShort(size);
         for (int i = 1; i < size; i++) {

src/java.xml/share/classes/com/sun/org/apache/bcel/internal/generic/ConstantPoolGen.java

@@ -50,10 +50,10 @@
  * JVM and that Double and Long constants need two slots.
  *
  * @see Constant
- * @LastModified: May 2022
+ * @LastModified: June 2022
  */
 public class ConstantPoolGen {
-    public static final int CONSTANT_POOL_SIZE = 65536;
+    public static final int CONSTANT_POOL_SIZE = 65535;
     private static final int DEFAULT_BUFFER_SIZE = 256;
     private int size;
     private Constant[] constants;
@@ -81,6 +81,19 @@ private static class Index {
      * @param cs array of given constants, new ones will be appended
      */
     public ConstantPoolGen(final Constant[] cs) {
+        /*
+         * To be logically/programmatically correct, the size of the constant pool
+         * shall not exceed the size limit as the code below does a copy and then
+         * walk through the whole array.
+         * This is however, not used by XSLT (or the java.xml implementation),
+         * and only happens when BCELifier is called (see BCELifier).
+        */
+        if (cs.length > CONSTANT_POOL_SIZE) {
+            throw new RuntimeException("The number of constants " + cs.length
+                    + " is over the size limit of the constant pool: "
+                    + CONSTANT_POOL_SIZE);
+        }
+
         final StringBuilder sb = new StringBuilder(DEFAULT_BUFFER_SIZE);
 
         size = Math.min(Math.max(DEFAULT_BUFFER_SIZE, cs.length + 64), CONSTANT_POOL_SIZE);
@@ -215,8 +228,8 @@ protected void adjustSize() {
         // 3 extra spaces are needed as some entries may take 3 slots
         if (index + 3 >= CONSTANT_POOL_SIZE) {
             throw new RuntimeException("The number of constants " + (index + 3)
-                    + " is over the size of the constant pool: "
-                    + (CONSTANT_POOL_SIZE - 1));
+                    + " is over the size limit of the constant pool: "
+                    + CONSTANT_POOL_SIZE);
         }
 
         if (index + 3 >= size) {