trunk/chemistry-opencmis-commons/chemistry-opencmis-commons-impl/src/main/java/org/apache/chemistry/opencmis/commons/impl/json/JSONArray.java

/*
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you 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.apache.chemistry.opencmis.commons.impl.json;

import java.io.IOException;
import java.io.Writer;
import java.util.ArrayList;
import java.util.List;

/**
 * A JSON array. JSONObject supports java.util.List interface.
 * 
 * (Taken from JSON.simple <http://code.google.com/p/json-simple/> and modified
 * for OpenCMIS.)
 * 
 * @author FangYidong<fangyidong@yahoo.com.cn>
 */
public class JSONArray extends ArrayList<Object> implements List<Object>, JSONAware, JSONStreamAware {
    private static final long serialVersionUID = 3957988303675231981L;

    /**
     * Encode a list into JSON text and write it to out. If this list is also a
     * JSONStreamAware or a JSONAware, JSONStreamAware and JSONAware specific
     * behaviours will be ignored at this top level.
     * 
     * @see org.json.simple.JSONValue#writeJSONString(Object, Writer)
     * 
     * @param list
     * @param out
     */
    public static void writeJSONString(List<Object> list, Writer out) throws IOException {
        if (list == null) {
            out.write("null");
            return;
        }

        boolean first = true;

        out.write('[');
        for (Object value : list) {
            if (first) {
                first = false;
            } else {
                out.write(',');
            }

            if (value == null) {
                out.write("null");
                continue;
            }

            JSONValue.writeJSONString(value, out);
        }
        out.write(']');
    }

    public void writeJSONString(Writer out) throws IOException {
        writeJSONString(this, out);
    }

    /**
     * Convert a list to JSON text. The result is a JSON array. If this list is
     * also a JSONAware, JSONAware specific behaviours will be omitted at this
     * top level.
     * 
     * @see org.json.simple.JSONValue#toJSONString(Object)
     * 
     * @param list
     * @return JSON text, or "null" if list is null.
     */
    public static String toJSONString(List<Object> list) {
        if (list == null) {
            return "null";
        }

        boolean first = true;
        StringBuilder sb = new StringBuilder();

        sb.append('[');
        for (Object value : list) {
            if (first) {
                first = false;
            } else {
                sb.append(',');
            }

            if (value == null) {
                sb.append("null");
                continue;
            }
            sb.append(JSONValue.toJSONString(value));
        }
        sb.append(']');
        return sb.toString();
    }

    public String toJSONString() {
        return toJSONString(this);
    }

    public String toString() {
        return toJSONString();
    }
}