/*
* Copyright (C) 2001 Mika Riekkinen, Joni Suominen
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
package alt.jiapi.instrumentor;
import java.util.ArrayList;
import java.util.Iterator;
import java.util.List;
import org.apache.log4j.Category;
import alt.jiapi.Instrumentor;
import alt.jiapi.Runtime;
import alt.jiapi.reflect.InstructionList;
/**
* This Instrumentor gets in an InstructionList and
* selects zero or more instructions from end of the instruction list
* given.
*
* @author Mika Riekkinen
* @author Joni Suominen
* @version $Revision: 1.9 $ $Date: 2004/03/15 14:47:53 $
*/
public class TailInstrumentor extends AbstractInstrumentor {
private static Category log = Runtime.getLogCategory(TailInstrumentor.class);
/**
* Number of instructions this Instrumentor applies to.
*/
protected int instructionCount = 0;
/**
* Constructor. Selects zero instructions from the enf of the list.
* Selecting zero instructions acts as a marker to end of the list.
*/
public TailInstrumentor() {
this(0);
}
/**
* This constructor selects zero or more instructions from the end of the
* list.
*
* @param instructionCount number of instructions to select
*/
public TailInstrumentor(int instructionCount) {
log.info("Instruction count " + instructionCount);
if (instructionCount < 0) {
throw new IllegalArgumentException(instructionCount + " < 0");
}
this.instructionCount = instructionCount;
}
/**
* Selects instructionCount instructions from the end of the
* InstructionList given.
*
* @param il InstructionList to consider
* @see #instructionCount
*/
public void instrument(InstructionList il) {
log.info("Instrumenting " + getCurrentClass().getName() + "." +
il.getDeclaringMethod().getName());
InstructionList view;
if (instructionCount > il.size()) {
log.warn("List size exceeded: instructions needed : " +
instructionCount + ", available " + il.size() +
". Using all that is available.");
view = il.createView(0, il.size());
}
else {
view = il.createView(il.size() - instructionCount, il.size());
}
forward(view);
}
}