SwitchTouchPointDescriptor.java

/*
 * Cobertura - http://cobertura.sourceforge.net/
 *
 * Copyright (C) 2011 Piotr Tabor
 *
 * Note: This file is dual licensed under the GPL and the Apache
 * Source License (so that it can be used from both the main
 * Cobertura classes and the ant tasks).
 *
 * Cobertura is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published
 * by the Free Software Foundation; either version 2 of the License,
 * or (at your option) any later version.
 *
 * Cobertura 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
 * General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with Cobertura; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307
 * USA
 */

package net.sourceforge.cobertura.instrument.tp;

import net.sourceforge.cobertura.coveragedata.LineData;
import org.objectweb.asm.Label;

import java.util.*;
import java.util.concurrent.atomic.AtomicInteger;

/**
 * Class representing a touch-point connected to a a SWITCH instruction in a source-code
 * <p/>
 * <p>A SWITCH touch-point uses one more counter then distinct number destination labels ({@link #getCountersForLabelsCnt()}).<br/>
 * One 'internal' counterId ({@link #counterId}) is a special identifier of SWITCH statement (used in runtime), but in fact we don't expect any
 * incrementation of the counter. We implemented this to use a counterId because we are storing the value inside 'internal variable' and we need to be sure
 * that the value is connected to the last seen SWITCH statement.<br/>
 * <p/>
 * Or other counterIds represents different branches (different destination labels of the switch).
 * </p>
 * <p/>
 * <p>We also storing a {@link #methodName} and a {@link #methodSignature} (consider to move this fields into {@link TouchPointDescriptor}).
 * Those fields are needed to properly create instance of {@link LineData}. </p>
 *
 * @author piotr.tabor@gmail.com
 */
public class SwitchTouchPointDescriptor extends TouchPointDescriptor {
	private final Label defaultDestinationLabel;
	private final Label[] labels;
	/**
	 * Encoded as: {@link org.objectweb.asm.commons#AnalyzerAdapter#stack}
	 */
	private final String enum_type;

	private Integer counterId;
	private Map<Label, Integer> label2counterId;

	/**
	 * Creates o new switch-touch point.
	 *
	 * @param eventId     - eventId connected to the SWITCH instruction
	 * @param currentLine - line number of the switch
	 * @param def         - internal identifier of a default destination label
	 * @param labels      - table of other destination labels for different values (duplicates allowed)
	 */
	public SwitchTouchPointDescriptor(int eventId, int currentLine, Label def,
			Label[] labels, String enum_type) {
		super(eventId, currentLine);
		this.labels = labels;
		this.defaultDestinationLabel = def;
		this.enum_type = enum_type;
	}

	public Integer getCounterId() {
		return counterId;
	}

	public void setCounterId(Integer counterId) {
		this.counterId = counterId;
	}

	@Override
	public int assignCounters(AtomicInteger idGenerator) {
		counterId = idGenerator.incrementAndGet();
		label2counterId = new HashMap<Label, Integer>();
		int idp = idGenerator.incrementAndGet();
		label2counterId.put(defaultDestinationLabel, idp);
		int i = 0;
		for (Label l : labels) {
			i++;
			idp = idGenerator.incrementAndGet();
			label2counterId.put(l, idp);
		}
		return i + 2;
	}

	public Integer getCounterIdForLabel(Label label) {
		return label2counterId.get(label);
	}

	public Collection<Integer> getCountersForLabels() {
		return label2counterId.values();
	}

	/**
	 * <p>Works before calling 'assignCounters'</p>
	 *
	 * @return Number of distinct destination labels of the SWITCH (It's the same as number of branches supported by the switch).
	 */
	public int getCountersForLabelsCnt() {
		Set<Label> l = new HashSet<Label>(Arrays.asList(labels));
		l.add(defaultDestinationLabel);
		return l.size();
	}

	public String getEnumType() {
		return enum_type;
	}

}