# ExecutionData.java

    /*******************************************************************************
     * Copyright (c) 2009, 2013 Mountainminds GmbH & Co. KG and Contributors
     * All rights reserved. This program and the accompanying materials
     * are made available under the terms of the Eclipse Public License v1.0
     * which accompanies this distribution, and is available at
     * http://www.eclipse.org/legal/epl-v10.html
     *
     * Contributors:
     *    Marc R. Hoffmann - initial API and implementation
     *
     *******************************************************************************/
    package org.jacoco.core.data;

    import static java.lang.String.format;

    import java.util.Arrays;

    /**
     * Execution data for a single Java class. While instances are immutable care
     * has to be taken about the probe data array of type <code>boolean[]</code>
     * which can be modified.
     */
    public final class ExecutionData {

    	private final long id;

    	private final String name;

    	private final boolean[] probes;

    	/**
    	 * Creates a new {@link ExecutionData} object with the given probe data.
    	 *
    	 * @param id
    	 *            class identifier
    	 * @param name
    	 *            VM name
    	 * @param probes
    	 *            probe data
    	 */
    	public ExecutionData(final long id, final String name,
    			final boolean[] probes) {
    		this.id = id;
    		this.name = name;
    		this.probes = probes;
    	}

    	/**
    	 * Creates a new {@link ExecutionData} object with the given probe data
    	 * length. All probes are set to <code>false</code>.
    	 *
    	 * @param id
    	 *            class identifier
    	 * @param name
    	 *            VM name
    	 * @param probeCount
    	 *            probe count
    	 */
    	public ExecutionData(final long id, final String name, final int probeCount) {
    		this.id = id;
    		this.name = name;
    		this.probes = new boolean[probeCount];
    	}

    	/**
    	 * Return the unique identifier for this class. The identifier is the CRC64
    	 * checksum of the raw class file definition.
    	 *
    	 * @return class identifier
    	 */
    	public long getId() {
    		return id;
    	}

    	/**
    	 * The VM name of the class.
    	 *
    	 * @return VM name
    	 */
    	public String getName() {
    		return name;
    	}

    	/**
    	 * Returns the execution data probes. A value of <code>true</code> indicates
    	 * that the corresponding probe was executed.
    	 *
    	 * @return probe data
    	 */
    	public boolean[] getProbes() {
    		return probes;
    	}

    	/**
    	 * Sets all probes to <code>false</code>.
    	 */
    	public void reset() {
    		Arrays.fill(probes, false);
    	}

    	/**
    	 * Merges the given execution data into the probe data of this object. I.e.
    	 * a probe entry in this object is marked as executed (<code>true</code>) if
    	 * this probe or the corresponding other probe was executed. So the result
    	 * is
    	 *
    	 * <pre>
    	 * A or B
    	 * </pre>
    	 *
    	 * The probe array of the other object is not modified.
    	 *
    	 * @param other
    	 *            execution data to merge
    	 */
    	public void merge(final ExecutionData other) {
    		merge(other, true);
    	}

    	/**
    	 * Merges the given execution data into the probe data of this object. A
    	 * probe in this object is set to the value of <code>flag</code> if the
    	 * corresponding other probe was executed. For <code>flag==true</code> this
    	 * corresponds to
    	 *
    	 * <pre>
    	 * A or B
    	 * </pre>
    	 *
    	 * For <code>flag==true</code> this can be considered as a subtraction
    	 *
    	 * <pre>
    	 * A and not B
    	 * </pre>
    	 *
    	 * The probe array of the other object is not modified.
    	 *
    	 * @param other
    	 *            execution data to merge
    	 * @param flag
    	 *            merge mode
    	 */
    	public void merge(final ExecutionData other, final boolean flag) {
    		assertCompatibility(other.getId(), other.getName(),
    				other.getProbes().length);
    		final boolean[] otherData = other.getProbes();
    		for (int i = 0; i < probes.length; i++) {
    			if (otherData[i]) {
    				probes[i] = flag;
    			}
    		}
    	}

    	/**
    	 * Asserts that this execution data object is compatible with the given
    	 * parameters. The purpose of this check is to detect a very unlikely class
    	 * id collision.
    	 *
    	 * @param id
    	 *            other class id, must be the same
    	 * @param name
    	 *            other name, must be equal to this name
    	 * @param probecount
    	 *            probe data length, must be the same as for this data
    	 * @throws IllegalStateException
    	 *             if the given parameters do not match this instance
    	 */
    	public void assertCompatibility(final long id, final String name,
    			final int probecount) throws IllegalStateException {
    		if (this.id != id) {
    			throw new IllegalStateException(format(
    					"Different ids (%016x and %016x).", Long.valueOf(this.id),
    					Long.valueOf(id)));
    		}
    		if (!this.name.equals(name)) {
    			throw new IllegalStateException(format(
    					"Different class names %s and %s for id %016x.", this.name,
    					name, Long.valueOf(id)));
    		}
    		if (this.probes.length != probecount) {
    			throw new IllegalStateException(format(
    					"Incompatible execution data for class %s with id %016x.",
    					name, Long.valueOf(id)));
    		}
    	}

    	@Override
    	public String toString() {
    		return String.format("ExecutionData[name=%s, id=%016x]", name,
    				Long.valueOf(id));
    	}
    }