Java tutorial
/******************************************************************************* *Copyright (c) 2009 Eucalyptus Systems, Inc. * * This program is free software: you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation, only version 3 of the License. * * * This file is distributed in the hope that it will be useful, but WITHOUT * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License * for more details. * * You should have received a copy of the GNU General Public License along * with this program. If not, see <http://www.gnu.org/licenses/>. * * Please contact Eucalyptus Systems, Inc., 130 Castilian * Dr., Goleta, CA 93101 USA or visit <http://www.eucalyptus.com/licenses/> * if you need additional information or have any questions. * * This file may incorporate work covered under the following copyright and * permission notice: * * Software License Agreement (BSD License) * * Copyright (c) 2008, Regents of the University of California * All rights reserved. * * Redistribution and use of this software in source and binary forms, with * or without modification, are permitted provided that the following * conditions are met: * * Redistributions of source code must retain the above copyright notice, * this list of conditions and the following disclaimer. * * Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS * IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A * PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER * OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. USERS OF * THIS SOFTWARE ACKNOWLEDGE THE POSSIBLE PRESENCE OF OTHER OPEN SOURCE * LICENSED MATERIAL, COPYRIGHTED MATERIAL OR PATENTED MATERIAL IN THIS * SOFTWARE, AND IF ANY SUCH MATERIAL IS DISCOVERED THE PARTY DISCOVERING * IT MAY INFORM DR. RICH WOLSKI AT THE UNIVERSITY OF CALIFORNIA, SANTA * BARBARA WHO WILL THEN ASCERTAIN THE MOST APPROPRIATE REMEDY, WHICH IN * THE REGENTS DISCRETION MAY INCLUDE, WITHOUT LIMITATION, REPLACEMENT * OF THE CODE SO IDENTIFIED, LICENSING OF THE CODE SO IDENTIFIED, OR * WITHDRAWAL OF THE CODE CAPABILITY TO THE EXTENT NEEDED TO COMPLY WITH * ANY SUCH LICENSES OR RIGHTS. *******************************************************************************/ package edu.ucsb.eucalyptus.admin.client.extensions.store; import java.util.List; import java.util.ArrayList; import com.google.gwt.core.client.GWT; import com.google.gwt.json.client.JSONNumber; import com.google.gwt.json.client.JSONString; import com.google.gwt.json.client.JSONValue; import com.google.gwt.json.client.JSONObject; import com.google.gwt.json.client.JSONParser; import com.google.gwt.json.client.JSONException; import com.google.gwt.json.client.JSONBoolean; import com.google.gwt.json.client.JSONArray; public class JSONUtil { static public JSONObject parseObject(String data) { JSONObject jsonObject = null; try { JSONValue jsonValue = JSONParser.parse(data); jsonObject = jsonValue.isObject(); } catch (JSONException e) { GWT.log("Tried to parse bad JSON data", e); JSONValue jsonValue = JSONParser.parse("{\"error-message\": \"Received bad JSON data.\"}"); jsonObject = jsonValue.isObject(); } return jsonObject; } static String asString(JSONValue value) { if (value != null) { JSONString string = value.isString(); if (string != null) { return string.stringValue(); } } return null; } static Integer asInteger(JSONValue value) { if (value != null) { JSONNumber number = value.isNumber(); if (number != null) { return (int) number.doubleValue(); } } return null; } static int asInt(JSONValue value, int defaultResult) { if (value != null) { JSONNumber number = value.isNumber(); if (number != null) { return (int) number.doubleValue(); } } return defaultResult; } static boolean asBoolean(JSONValue value, boolean defaultResult) { if (value != null) { JSONBoolean bool = value.isBoolean(); if (bool != null) { return bool.booleanValue(); } } return defaultResult; } public static interface ObjectAdapter<T> { T adaptObject(JSONObject object); } public static <T> List<T> adaptArray(JSONValue arrayValue, ObjectAdapter<T> adapter) { List<T> result = new ArrayList<T>(); if (arrayValue != null && arrayValue.isArray() != null) { JSONArray array = arrayValue.isArray(); for (int i = 0; i != array.size(); i++) { JSONObject object = array.get(i).isObject(); if (object != null) { result.add(adapter.adaptObject(object)); } } } return result; } }