ctf: Make events immutable

[deliverable/tracecompass.git] / org.eclipse.linuxtools.ctf.core / src / org / eclipse / linuxtools / ctf / core / event / types / Definition.java

/*******************************************************************************
 * Copyright (c) 2011, 2013 Ericsson, Ecole Polytechnique de Montreal and others
 *
 * 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: Matthew Khouzam - Initial API and implementation
 * Contributors: Simon Marchi - Initial API and implementation
 *******************************************************************************/

package org.eclipse.linuxtools.ctf.core.event.types;

import org.eclipse.jdt.annotation.NonNull;
import org.eclipse.linuxtools.ctf.core.event.scope.IDefinitionScope;
import org.eclipse.linuxtools.ctf.core.event.scope.LexicalScope;

/**
 * A CTF definition
 *
 * A definition is like an object of a declaration class. It fills the
 * declaration with values. <br>
 * An example: <br>
 * int i = 0; <br>
 * <b>int</b> is the declaration.<br>
 * <b>i</b> is the definition.<br>
 * <b>0</b> is the value assigned to the definition, not the declaration.<br>
 *
 * @version 1.0
 * @author Matthew Khouzam
 * @author Simon Marchi
 */
public abstract class Definition {

    // ------------------------------------------------------------------------
    // Attributes
    // ------------------------------------------------------------------------

    private final String fFieldName;

    /** The complete path of this field */
    private final LexicalScope fPath;

    private final IDefinitionScope fDefinitionScope;

    @NonNull
    private final IDeclaration fDeclaration;

    // ------------------------------------------------------------------------
    // Constructors
    // ------------------------------------------------------------------------

    /**
     * Constructor
     *
     * @param declaration
     *            the event declaration
     *
     * @param definitionScope
     *            the definition is in a scope, (normally a struct) what is it?
     * @param fieldName
     *            the name of the definition. (it is a field in the parent
     *            scope)
     * @since 3.0
     */
    public Definition(@NonNull IDeclaration declaration, IDefinitionScope definitionScope, @NonNull String fieldName) {
        fDeclaration = declaration;
        fDefinitionScope = definitionScope;
        fFieldName = fieldName;
        fPath = fDeclaration.getPath(definitionScope, fieldName);
    }

    // ------------------------------------------------------------------------
    // Getters
    // ------------------------------------------------------------------------

    /**
     * Get the field name in its container.
     *
     * @return The field name
     * @since 2.0
     */
    protected String getFieldName() {
        return fFieldName;
    }

    /**
     * Get the complete path of this field.
     *
     * @return The path
     * @since 3.0
     */
    public LexicalScope getScopePath() {
        return fPath;
    }

    /**
     * Get the definition scope in which this definition is found.
     *
     * The complete path of a definition is thus the path of the definition
     * scope DOT the name of the definition (name of the field in its container)
     *
     * @return The definition scope
     * @since 3.0
     */
    protected IDefinitionScope getDefinitionScope() {
        return fDefinitionScope;
    }

    // ------------------------------------------------------------------------
    // Operations
    // ------------------------------------------------------------------------

    /**
     *
     * @return gets the declaration of a datatype
     *
     */
    @NonNull
    public IDeclaration getDeclaration() {
        return fDeclaration;
    }

    @Override
    public String toString() {
        return fPath.toString() + '[' + Integer.toHexString(hashCode()) + ']';
    }
}