jaxp/src/com/sun/org/apache/bcel/internal/generic/LDC.java
changeset 12457 c348e06f0e82
parent 6 7f561c08de6b
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/jaxp/src/com/sun/org/apache/bcel/internal/generic/LDC.java	Thu Apr 12 08:38:26 2012 -0700
@@ -0,0 +1,175 @@
+/*
+ * reserved comment block
+ * DO NOT REMOVE OR ALTER!
+ */
+package com.sun.org.apache.bcel.internal.generic;
+
+/* ====================================================================
+ * The Apache Software License, Version 1.1
+ *
+ * Copyright (c) 2001 The Apache Software Foundation.  All rights
+ * reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ *
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ *
+ * 3. The end-user documentation included with the redistribution,
+ *    if any, must include the following acknowledgment:
+ *       "This product includes software developed by the
+ *        Apache Software Foundation (http://www.apache.org/)."
+ *    Alternately, this acknowledgment may appear in the software itself,
+ *    if and wherever such third-party acknowledgments normally appear.
+ *
+ * 4. The names "Apache" and "Apache Software Foundation" and
+ *    "Apache BCEL" must not be used to endorse or promote products
+ *    derived from this software without prior written permission. For
+ *    written permission, please contact apache@apache.org.
+ *
+ * 5. Products derived from this software may not be called "Apache",
+ *    "Apache BCEL", nor may "Apache" appear in their name, without
+ *    prior written permission of the Apache Software Foundation.
+ *
+ * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+ * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED.  IN NO EVENT SHALL THE APACHE SOFTWARE FOUNDATION OR
+ * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
+ * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
+ * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+ * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
+ * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ * ====================================================================
+ *
+ * This software consists of voluntary contributions made by many
+ * individuals on behalf of the Apache Software Foundation.  For more
+ * information on the Apache Software Foundation, please see
+ * <http://www.apache.org/>.
+ */
+import java.io.*;
+import com.sun.org.apache.bcel.internal.util.ByteSequence;
+
+/**
+ * LDC - Push item from constant pool.
+ *
+ * <PRE>Stack: ... -&gt; ..., item</PRE>
+ *
+ * @author  <A HREF="mailto:markus.dahm@berlin.de">M. Dahm</A>
+ */
+public class LDC extends CPInstruction
+  implements PushInstruction, ExceptionThrower, TypedInstruction {
+  /**
+   * Empty constructor needed for the Class.newInstance() statement in
+   * Instruction.readInstruction(). Not to be used otherwise.
+   */
+  LDC() {}
+
+  public LDC(int index) {
+    super(com.sun.org.apache.bcel.internal.Constants.LDC_W, index);
+    setSize();
+  }
+
+  // Adjust to proper size
+  protected final void setSize() {
+    if(index <= com.sun.org.apache.bcel.internal.Constants.MAX_BYTE) { // Fits in one byte?
+      opcode = com.sun.org.apache.bcel.internal.Constants.LDC;
+      length = 2;
+    } else {
+      opcode = com.sun.org.apache.bcel.internal.Constants.LDC_W;
+      length = 3;
+    }
+  }
+
+  /**
+   * Dump instruction as byte code to stream out.
+   * @param out Output stream
+   */
+  public void dump(DataOutputStream out) throws IOException {
+    out.writeByte(opcode);
+
+    if(length == 2)
+      out.writeByte(index);
+    else // Applies for LDC_W
+      out.writeShort(index);
+  }
+
+  /**
+   * Set the index to constant pool and adjust size.
+   */
+  public final void setIndex(int index) {
+    super.setIndex(index);
+    setSize();
+  }
+
+  /**
+   * Read needed data (e.g. index) from file.
+   */
+  protected void initFromFile(ByteSequence bytes, boolean wide)
+       throws IOException
+  {
+    length = 2;
+    index  = bytes.readUnsignedByte();
+  }
+
+  public Object getValue(ConstantPoolGen cpg) {
+    com.sun.org.apache.bcel.internal.classfile.Constant c = cpg.getConstantPool().getConstant(index);
+
+    switch(c.getTag()) {
+      case com.sun.org.apache.bcel.internal.Constants.CONSTANT_String:
+        int i = ((com.sun.org.apache.bcel.internal.classfile.ConstantString)c).getStringIndex();
+        c = cpg.getConstantPool().getConstant(i);
+        return ((com.sun.org.apache.bcel.internal.classfile.ConstantUtf8)c).getBytes();
+
+    case com.sun.org.apache.bcel.internal.Constants.CONSTANT_Float:
+        return new Float(((com.sun.org.apache.bcel.internal.classfile.ConstantFloat)c).getBytes());
+
+    case com.sun.org.apache.bcel.internal.Constants.CONSTANT_Integer:
+        return new Integer(((com.sun.org.apache.bcel.internal.classfile.ConstantInteger)c).getBytes());
+
+    default: // Never reached
+      throw new RuntimeException("Unknown or invalid constant type at " + index);
+      }
+  }
+
+  public Type getType(ConstantPoolGen cpg) {
+    switch(cpg.getConstantPool().getConstant(index).getTag()) {
+    case com.sun.org.apache.bcel.internal.Constants.CONSTANT_String:  return Type.STRING;
+    case com.sun.org.apache.bcel.internal.Constants.CONSTANT_Float:   return Type.FLOAT;
+    case com.sun.org.apache.bcel.internal.Constants.CONSTANT_Integer: return Type.INT;
+    default: // Never reached
+      throw new RuntimeException("Unknown or invalid constant type at " + index);
+    }
+  }
+
+  public Class[] getExceptions() {
+    return com.sun.org.apache.bcel.internal.ExceptionConstants.EXCS_STRING_RESOLUTION;
+  }
+
+  /**
+   * Call corresponding visitor method(s). The order is:
+   * Call visitor methods of implemented interfaces first, then
+   * call methods according to the class hierarchy in descending order,
+   * i.e., the most specific visitXXX() call comes last.
+   *
+   * @param v Visitor object
+   */
+  public void accept(Visitor v) {
+    v.visitStackProducer(this);
+    v.visitPushInstruction(this);
+    v.visitExceptionThrower(this);
+    v.visitTypedInstruction(this);
+    v.visitCPInstruction(this);
+    v.visitLDC(this);
+  }
+}