1 files changed, 142 insertions, 0 deletions
diff --git a/org.eclipse.core.variables/src/org/eclipse/core/internal/variables/ContributedValueVariable.java b/org.eclipse.core.variables/src/org/eclipse/core/internal/variables/ContributedValueVariable.java
new file mode 100644
index 000000000..5a3d23189
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+++ b/org.eclipse.core.variables/src/org/eclipse/core/internal/variables/ContributedValueVariable.java
@@ -0,0 +1,142 @@
+/*******************************************************************************
+ * Copyright (c) 2000, 2006 IBM Corporation 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:
+ *     IBM Corporation - initial API and implementation
+ *******************************************************************************/
+package org.eclipse.core.internal.variables;
+
+import org.eclipse.core.runtime.CoreException;
+import org.eclipse.core.runtime.IConfigurationElement;
+import org.eclipse.core.variables.IValueVariable;
+import org.eclipse.core.variables.IValueVariableInitializer;
+import org.eclipse.core.variables.VariablesPlugin;
+import org.eclipse.osgi.util.NLS;
+
+/**
+ * Implementation of a value variable.
+ */
+public class ContributedValueVariable extends StringVariable implements IValueVariable {
+	
+	/**
+	 * Variable value or <code>null</code> if none 
+	 */
+	private String fValue;
+	
+	/**
+	 * Whether this variable's value has been initialized
+	 */
+	private boolean fInitialized = false;
+	
+	/**
+	 * Whether this variable is read only.  If true, users cannot change the value.
+	 */
+	private boolean fReadOnly;
+	
+	/**
+	 * Constructs a new value variable with the given name, description, read only
+	 * property and associated configuration element.  The value will be initialized
+	 * from the configuration element the first time getValue() is called.
+	 * 
+	 * @param name variable name
+	 * @param description variable description or <code>null</code>
+	 * @param readOnly whether the variable should be a read only variable
+	 * @param configurationElement configuration element
+	 */
+	public ContributedValueVariable(String name, String description, boolean readOnly, IConfigurationElement configurationElement) {
+		super(name, description, configurationElement);
+		fReadOnly = readOnly;
+	}
+	
+	/* (non-Javadoc)
+	 * @see org.eclipse.core.variables.IValueVariable#setValue(java.lang.String)
+	 */
+	public void setValue(String value) {
+		if (!isReadOnly() || !isInitialized()){
+			fValue = value;
+			setInitialized(true);
+			StringVariableManager.getDefault().notifyChanged(this);
+		}
+	}
+	
+	/* (non-Javadoc)
+	 * @see org.eclipse.core.variables.IValueVariable#getValue()
+	 */
+	public String getValue() {
+		if (!isInitialized()) {
+			initialize();
+		}
+		return fValue;
+	}
+
+	/**
+	 * Initialize this variable's value from the configuration element.
+	 */
+	private void initialize() {
+		if (getConfigurationElement() != null) {
+			// check for a explicit value specified in plug-in XML
+			String value = getConfigurationElement().getAttribute("initialValue"); //$NON-NLS-1$
+			if (value == null) {
+				// check for initializer
+				String className = getConfigurationElement().getAttribute("initializerClass"); //$NON-NLS-1$
+				if (className != null) {
+					try {
+						Object object = getConfigurationElement().createExecutableExtension("initializerClass"); //$NON-NLS-1$
+						if (object instanceof IValueVariableInitializer) {
+							IValueVariableInitializer initializer = (IValueVariableInitializer)object;
+							initializer.initialize(this);
+						} else {
+							VariablesPlugin.logMessage(NLS.bind("Unable to initialize variable {0} - initializer must be an instance of IValueVariableInitializer.", new String[]{getName()}), null); //$NON-NLS-1$
+						}
+					} catch (CoreException e) {
+						VariablesPlugin.logMessage(NLS.bind("Unable to initialize variable {0}",new String[]{getName()}), e); //$NON-NLS-1$
+					}
+				}
+			} else {
+				setValue(value);
+			}
+		}
+		setInitialized(true);
+	}
+
+	/**
+	 * Returns whether this variable has been initialized with a value by one of:
+	 * <ul>
+	 * <li><code>setValue(String)</code></li>
+	 * <li>its configuration element's <code>initialValue</code> attribute</li>
+	 * <li>its configuration element's initializer</li>
+	 * </ul>
+	 * @return whether this variable has been initialized with a value
+	 */	
+	protected boolean isInitialized() {
+		return fInitialized;
+	} 
+	
+	/**
+	 * Sets whether this variable has been initialized with a value.
+	 *  
+	 * @param initialized whether this variable has been initialized
+	 */
+	protected void setInitialized(boolean initialized) {
+		fInitialized = initialized;
+	}
+
+	/* (non-Javadoc)
+	 * @see org.eclipse.core.variables.IValueVariable#isReadOnly()
+	 */
+	public boolean isReadOnly() {
+		return fReadOnly;
+	}
+
+	/* (non-Javadoc)
+	 * @see org.eclipse.core.variables.IValueVariable#isContributed()
+	 */
+	public boolean isContributed() {
+		return getConfigurationElement() != null;
+	}
+
+}