plastic/src/external/java/org/apache/tapestry5/internal/plastic/asm/CurrentFrame.java

// ASM: a very small and fast Java bytecode manipulation framework
// Copyright (c) 2000-2011 INRIA, France Telecom
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//    this software without specific prior written permission.
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package org.apache.tapestry5.internal.plastic.asm;

/**
 * Information about the input stack map frame at the "current" instruction of a method. This is
 * implemented as a Frame subclass for a "basic block" containing only one instruction.
 *
 * @author Eric Bruneton
 */
final class CurrentFrame extends Frame {

  CurrentFrame(final Label owner) {
    super(owner);
  }

  /**
   * Sets this CurrentFrame to the input stack map frame of the next "current" instruction, i.e. the
   * instruction just after the given one. It is assumed that the value of this object when this
   * method is called is the stack map frame status just before the given instruction is executed.
   */
  @Override
  void execute(
      final int opcode, final int arg, final Symbol symbolArg, final SymbolTable symbolTable) {
    super.execute(opcode, arg, symbolArg, symbolTable);
    Frame successor = new Frame(null);
    merge(symbolTable, successor, 0);
    copyFrom(successor);
  }
}