Property.java

/*******************************************************************************
 * Copyright (c) 2000, 2013 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
 *     asifrc@terpmail.umd.edu - bug 366337 (https://bugs.eclipse.org/bugs/show_bug.cgi?id=366337)
 *******************************************************************************/
package org.eclipse.ant.core;

import org.eclipse.core.runtime.CoreException;
import org.eclipse.core.variables.VariablesPlugin;

/**
 * Represents a Ant property. Clients may instantiate this class; it is not intended to be subclassed.
 * 
 * @since 2.1
 * @noextend This class is not intended to be subclassed by clients.
 */
public class Property {

	private String name;
	private String value;
	private String className;
	private IAntPropertyValueProvider valueProvider;
	private String pluginLabel;
	private ClassLoader loader;
	private boolean eclipseRuntime = true;

	public Property(String name, String value) {
		this.name = name;
		this.value = value;
	}

	public Property() {
	}

	/**
	 * Gets the name
	 * 
	 * @return Returns a String
	 */
	public String getName() {
		return name;
	}

	/**
	 * Sets the name
	 * 
	 * @param name
	 *            The name to set
	 */
	public void setName(String name) {
		this.name = name;
	}

	/*
	 * @see Object#equals()
	 */
	@Override
	public boolean equals(Object other) {
		if (other != null && other.getClass().equals(getClass())) {
			Property elem = (Property) other;
			return name.equals(elem.getName());
		}
		return false;
	}

	/*
	 * @see Object#hashCode()
	 */
	@Override
	public int hashCode() {
		return name.hashCode();
	}

	/**
	 * Returns the value. Equivalent to calling #getValue(true);
	 * 
	 * @return String
	 */
	public String getValue() {
		return getValue(true);
	}

	/**
	 * Returns the value.
	 * 
	 * @param substituteVariables
	 *            whether the value has any variables resolved.
	 * @return String
	 * @since 3.0
	 */
	public String getValue(boolean substituteVariables) {
		if (className != null) {
			Class<?> cls = null;
			try {
				cls = loader.loadClass(className);
			}
			catch (ClassNotFoundException e) {
				AntCorePlugin.log(e);
				return null;
			}
			try {
				valueProvider = (IAntPropertyValueProvider) cls.newInstance();
			}
			catch (InstantiationException e) {
				AntCorePlugin.log(e);
				return null;
			}
			catch (IllegalAccessException ex) {
				AntCorePlugin.log(ex);
				return null;
			}
			loader = null;
			className = null;
		}

		if (valueProvider != null) {
			return valueProvider.getAntPropertyValue(name);
		}
		if (substituteVariables) {
			try {
				String expanded = VariablesPlugin.getDefault().getStringVariableManager().performStringSubstitution(value);
				return expanded;
			}
			catch (CoreException e) {
				// do nothing
			}
		} else {
			return value;
		}
		return value;
	}

	/**
	 * Sets the value.
	 * 
	 * @param value
	 *            The value to set
	 */
	public void setValue(String value) {
		this.value = value;
	}

	/**
	 * Returns whether this Ant property has been created because of an extension point definition.
	 * 
	 * @return boolean
	 * @since 3.0
	 */
	public boolean isDefault() {
		return pluginLabel != null;
	}

	/**
	 * Sets the label of the plug-in that contributed this Ant property via an extension point.
	 * 
	 * @param pluginLabel
	 *            The label of the plug-in
	 * @since 3.0
	 */
	public void setPluginLabel(String pluginLabel) {
		this.pluginLabel = pluginLabel;
	}

	/**
	 * Returns the label of the plug-in that contributed this Ant property via an extension point.
	 * 
	 * @return pluginLabel The label of the plug-in
	 * @since 3.0
	 */
	public String getPluginLabel() {
		return this.pluginLabel;
	}

	/**
	 * Sets the name of the class that is an <code>IAntPropertyValueProvider</code> to be used to dynamically provide a value for this property. Sets
	 * the class loader to load the <code>IAntPropertyValueProvider</code> to be used to dynamically provide a value for this property.
	 * 
	 * @param className
	 *            The name of the value provider class to use to resolve the value of this property
	 * @param loader
	 *            The class loader to use to load the value provider class to use to resolve the value of this property
	 * @since 3.0
	 */
	public void setValueProvider(String className, ClassLoader loader) {
		this.className = className;
		this.loader = loader;
	}

	/*
	 * (non-Javadoc)
	 * 
	 * @see java.lang.Object#toString()
	 */
	@Override
	public String toString() {
		StringBuffer buff = new StringBuffer("\""); //$NON-NLS-1$
		buff.append(getName());
		buff.append("\"= \""); //$NON-NLS-1$
		buff.append(getValue(false));
		buff.append("\""); //$NON-NLS-1$
		return buff.toString();
	}

	/**
	 * Returns whether this property requires the Eclipse runtime to be relevant. Defaults value is <code>true</code>
	 * 
	 * @return whether this property requires the Eclipse runtime
	 * @since 3.0
	 */
	public boolean isEclipseRuntimeRequired() {
		return eclipseRuntime;
	}

	public void setEclipseRuntimeRequired(boolean eclipseRuntime) {
		this.eclipseRuntime = eclipseRuntime;
	}
}