org.eclipse.linuxtools.ctf.core/src/org/eclipse/linuxtools/ctf/core/event/types/VariantDeclaration.java

   1 /*******************************************************************************
   2  * Copyright (c) 2011, 2014 Ericsson, Ecole Polytechnique de Montreal and others
   3  *
   4  * All rights reserved. This program and the accompanying materials are made
   5  * available under the terms of the Eclipse Public License v1.0 which
   6  * accompanies this distribution, and is available at
   7  * http://www.eclipse.org/legal/epl-v10.html
   8  *
   9  * Contributors: Matthew Khouzam - Initial API and implementation
  10  * Contributors: Simon Marchi - Initial API and implementation
  11  *******************************************************************************/
  12
  13 package org.eclipse.linuxtools.ctf.core.event.types;
  14
  15 import java.util.HashMap;
  16 import java.util.Map;
  17
  18 /**
  19  * A CTFC variant declaration.
  20  *
  21  * A variant is similar to a C union, only taking the minimum size of the types,
  22  * it is a compound data type that contains other datatypes in fields. they are
  23  * stored in an hashmap and indexed by names which are strings.
  24  *
  25  * @version 1.0
  26  * @author Matthew Khouzam
  27  * @author Simon Marchi
  28  */
  29 public class VariantDeclaration implements IDeclaration {
  30
  31     // ------------------------------------------------------------------------
  32     // Attributes
  33     // ------------------------------------------------------------------------
  34
  35     private String tag = null;
  36     private static final long alignment = 1;
  37     private final Map<String, IDeclaration> fields = new HashMap<>();
  38
  39     // ------------------------------------------------------------------------
  40     // Constructors
  41     // ------------------------------------------------------------------------
  42
  43     /**
  44      * Constructor
  45      */
  46     public VariantDeclaration() {
  47     }
  48
  49     // ------------------------------------------------------------------------
  50     // Getters/Setters/Predicates
  51     // ------------------------------------------------------------------------
  52
  53     /**
  54      * @return Does the variant have a tag
  55      */
  56     public boolean isTagged() {
  57         return tag != null;
  58     }
  59
  60     /**
  61      * Lookup if a field exists in the variant
  62      * @param fieldTag the field tag name
  63      * @return true = field tag exists
  64      */
  65     public boolean hasField(String fieldTag) {
  66         return fields.containsKey(fieldTag);
  67     }
  68
  69     /**
  70      * Sets the tag in a variant
  71      * @param tag the tag
  72      */
  73     public void setTag(String tag) {
  74         this.tag = tag;
  75     }
  76
  77     /**
  78      * Gets current variant tag
  79      * @return the variant tag.
  80      */
  81     public String getTag() {
  82         return this.tag;
  83     }
  84
  85     /**
  86      * Gets the fields of the variant
  87      * @return the fields of the variant
  88      * @since 2.0
  89      */
  90     public Map<String, IDeclaration> getFields() {
  91         return this.fields;
  92     }
  93
  94     @Override
  95     public long getAlignment() {
  96         return alignment;
  97     }
  98     // ------------------------------------------------------------------------
  99     // Operations
 100     // ------------------------------------------------------------------------
 101
 102     @Override
 103     public VariantDefinition createDefinition(IDefinitionScope definitionScope,
 104             String fieldName) {
 105         return new VariantDefinition(this, definitionScope, fieldName);
 106     }
 107
 108
 109     /**
 110      * Add a field to this CTF Variant
 111      *
 112      * @param fieldTag
 113      *            The tag of the new field
 114      * @param declaration
 115      *            The Declaration of this new field
 116      */
 117     public void addField(String fieldTag, IDeclaration declaration) {
 118         fields.put(fieldTag, declaration);
 119     }
 120
 121     @Override
 122     public String toString() {
 123         /* Only used for debugging */
 124         return "[declaration] variant[" + Integer.toHexString(hashCode()) + ']'; //$NON-NLS-1$
 125     }
 126
 127 }