net.sourceforge.phpeclipse.externaltools/src/net/sourceforge/phpdt/externaltools/internal/registry/ExternalToolVariableRegistry.java

   1 package net.sourceforge.phpdt.externaltools.internal.registry;
   2
   3 /**********************************************************************
   4  Copyright (c) 2002 IBM Corp. and others. All rights reserved.
   5  This file is made available under the terms of the Common Public License v1.0
   6  which accompanies this distribution, and is available at
   7  http://www.eclipse.org/legal/cpl-v10.html
   8  �
   9  Contributors:
  10  **********************************************************************/
  11
  12 import java.util.HashMap;
  13
  14 import net.sourceforge.phpdt.externaltools.model.IExternalToolConstants;
  15 import net.sourceforge.phpeclipse.externaltools.ExternalToolsPlugin;
  16
  17 import org.eclipse.core.runtime.IConfigurationElement;
  18 import org.eclipse.core.runtime.IExtension;
  19 import org.eclipse.core.runtime.IExtensionPoint;
  20 import org.eclipse.core.runtime.IExtensionRegistry;
  21 import org.eclipse.core.runtime.Platform;
  22
  23 /**
  24  * General registry reader for external tool variables.
  25  */
  26 public abstract class ExternalToolVariableRegistry {
  27         // Format of the variable extension points
  28         // <extension point="org.eclipse.ui.externalTools.***Variables>
  29         // <variable
  30         // tag={string}
  31         // description={string}
  32         // componentClass={string:IVariableComponent}
  33         // expanderClass={string:IVariable***Expander}>
  34         // </variable>
  35         // </extension>
  36         //
  37
  38         /**
  39          * Element and attribute tags of a variable extension.
  40          */
  41         /* package */static final String TAG_VARIABLE = "variable"; //$NON-NLS-1$
  42
  43         /* package */static final String TAG_TAG = "tag"; //$NON-NLS-1$
  44
  45         /* package */static final String TAG_DESCRIPTION = "description"; //$NON-NLS-1$
  46
  47         /* package */static final String TAG_COMPONENT_CLASS = "componentClass"; //$NON-NLS-1$
  48
  49         /* package */static final String TAG_EXPANDER_CLASS = "expanderClass"; //$NON-NLS-1$
  50
  51         /**
  52          * Table of variables where the key is the variable tag and the value is the
  53          * corresponding variable.
  54          */
  55         private HashMap variables;
  56
  57         /**
  58          * The extension point id to read the variables from
  59          */
  60         private String extensionPointId;
  61
  62         /**
  63          * The /** Creates a new registry and loads the variables.
  64          */
  65         public ExternalToolVariableRegistry(String extensionPointId) {
  66                 super();
  67                 this.extensionPointId = extensionPointId;
  68                 loadVariables();
  69         }
  70
  71         /**
  72          * Returns the variables in the registry
  73          */
  74         protected final void copyVariables(Object[] results) {
  75                 variables.values().toArray(results);
  76         }
  77
  78         /**
  79          * Returns the variable for the specified tag, or <code>null</code> if
  80          * none found.
  81          */
  82         protected final ExternalToolVariable findVariable(String tag) {
  83                 return (ExternalToolVariable) variables.get(tag);
  84         }
  85
  86         /**
  87          * Returns the number of variables in the registry.
  88          */
  89         public final int getVariableCount() {
  90                 return variables.size();
  91         }
  92
  93         /**
  94          * Load the available variables
  95          */
  96         private void loadVariables() {
  97                 variables = new HashMap();
  98                 IExtensionRegistry registry = Platform.getExtensionRegistry();
  99                 // IPluginRegistry registry = Platform.getPluginRegistry();
 100                 IExtensionPoint point = registry.getExtensionPoint(
 101                                 IExternalToolConstants.PLUGIN_ID, extensionPointId);
 102                 if (point != null) {
 103                         IExtension[] extensions = point.getExtensions();
 104                         for (int i = 0; i < extensions.length; i++) {
 105                                 IConfigurationElement[] elements = extensions[i]
 106                                                 .getConfigurationElements();
 107                                 for (int j = 0; j < elements.length; j++) {
 108                                         IConfigurationElement element = elements[j];
 109                                         if (element.getName().equals(TAG_VARIABLE)) {
 110                                                 String tag = element.getAttribute(TAG_TAG);
 111                                                 String description = element
 112                                                                 .getAttribute(TAG_DESCRIPTION);
 113                                                 String className = element
 114                                                                 .getAttribute(TAG_EXPANDER_CLASS);
 115
 116                                                 boolean valid = true;
 117                                                 if (tag == null || tag.length() == 0) {
 118                                                         valid = false;
 119                                                         ExternalToolsPlugin
 120                                                                         .getDefault()
 121                                                                         .log(
 122                                                                                         "Missing tag attribute value for variable element.", null); //$NON-NLS-1$
 123                                                 }
 124                                                 if (description == null || description.length() == 0) {
 125                                                         valid = false;
 126                                                         ExternalToolsPlugin
 127                                                                         .getDefault()
 128                                                                         .log(
 129                                                                                         "Missing description attribute value for variable element.", null); //$NON-NLS-1$
 130                                                 }
 131                                                 if (className == null || className.length() == 0) {
 132                                                         valid = false;
 133                                                         ExternalToolsPlugin
 134                                                                         .getDefault()
 135                                                                         .log(
 136                                                                                         "Missing expander class attribute value for variable element.", null); //$NON-NLS-1$
 137                                                 }
 138
 139                                                 if (valid)
 140                                                         variables.put(tag, newVariable(tag, description,
 141                                                                         element));
 142                                         }
 143                                 }
 144                         }
 145                 }
 146         }
 147
 148         /**
 149          * Creates a new variable from the specified information.
 150          */
 151         protected abstract ExternalToolVariable newVariable(String tag,
 152                         String description, IConfigurationElement element);
 153 }