/*
 * Copyright 2002-2006 the original author or authors.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package org.springframework.beans.propertyeditors;

import java.beans.PropertyEditorSupport;

import org.springframework.util.ClassUtils;
import org.springframework.util.StringUtils;

/**
 * Property editor for an array of {@link java.lang.Class Classes}, to enable
 * the direct population of a <code>Class[]</code> property without having to
 * use a <code>String</code> class name property as bridge.
 *
 * <p>Also supports "java.lang.String[]"-style array class names, in contrast
 * to the standard {@link Class#forName(String)} method.
 *
 * @author Rob Harrop
 * @since 2.0
 */
public class ClassArrayEditor extends PropertyEditorSupport {

	private final ClassLoader classLoader;


	/**
	 * Create a default <code>ClassEditor</code>, using the thread
	 * context <code>ClassLoader</code>.
	 */
	public ClassArrayEditor() {
		this(null);
	}

	/**
	 * Create a default <code>ClassArrayEditor</code>, using the given
	 * <code>ClassLoader</code>.
	 * @param classLoader the <code>ClassLoader</code> to use
	 * (or pass <code>null</code> for the thread context <code>ClassLoader</code>)
	 */
	public ClassArrayEditor(ClassLoader classLoader) {
		this.classLoader = classLoader != null
				? classLoader : ClassUtils.getDefaultClassLoader();
	}


	public void setAsText(String text) throws IllegalArgumentException {
		if (StringUtils.hasText(text)) {
			String[] classNames = StringUtils.commaDelimitedListToStringArray(text);
			Class[] classes = new Class[classNames.length];
			for (int i = 0; i < classNames.length; i++) {
				String className = classNames[i].trim();
				classes[i] = ClassUtils.resolveClassName(className, this.classLoader);
			}
			setValue(classes);
		}
		else {
			setValue(null);
		}
	}

	public String getAsText() {
		Class[] classes = (Class[]) getValue();
		if (classes == null || classes.length == 0) {
			return "";
		}
		return toCommaDelimitedString(classes);
	}


	private static String toCommaDelimitedString(Class[] classes) {
		StringBuffer buffer = new StringBuffer();
		for (int i = 0; i < classes.length; ++i) {
			if (i > 0) {
				buffer.append(",");
			}
			buffer.append(ClassUtils.getQualifiedName(classes[i]));
		}
		return buffer.toString();
	}

}