Java tutorial
/* * Copyright 2011 JBoss Inc * * 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.jbpm.formapi.client.form; import java.util.ArrayList; import java.util.HashMap; import java.util.List; import java.util.Map; import org.jbpm.formapi.common.reflect.ReflectionHelper; import org.jbpm.formapi.shared.api.FBScript; import org.jbpm.formapi.shared.api.FBValidation; import org.jbpm.formapi.shared.api.FormItemRepresentation; import org.jbpm.formapi.shared.api.FormRepresentation; import org.jbpm.formapi.shared.api.InputData; import org.jbpm.formapi.shared.api.Mappable; import org.jbpm.formapi.shared.api.OutputData; import org.jbpm.formapi.shared.form.FormEncodingException; import org.jbpm.formapi.shared.form.FormRepresentationDecoder; import org.jbpm.formapi.shared.menu.MenuItemDescription; import com.google.gwt.json.client.JSONArray; import com.google.gwt.json.client.JSONObject; import com.google.gwt.json.client.JSONParser; import com.google.gwt.json.client.JSONValue; /** * Decodes json to different objects on the client side */ public class FormRepresentationDecoderClient implements FormRepresentationDecoder { @Override public Object decode(Map<String, Object> data) throws FormEncodingException { if (data == null || data.isEmpty()) { return null; } String className = (String) data.get("@className"); Object obj = null; try { obj = ReflectionHelper.newInstance(className); if (obj instanceof Mappable) { Mappable item = (Mappable) obj; item.setDataMap(data); } else { throw new FormEncodingException("Cannot cast class " + obj.getClass().getName() + " to Mappable"); } } catch (Exception e) { throw new FormEncodingException("Couldn't instantiate class " + className, e); } return obj; } @Override public FormRepresentation decode(String code) throws FormEncodingException { FormRepresentation form = new FormRepresentation(); JSONValue json = JSONParser.parseLenient(code); if (json.isObject() != null) { JSONObject jsonObj = json.isObject(); if (jsonObj.get("action").isString() != null) { form.setAction(jsonObj.get("action").isString().stringValue()); } if (jsonObj.get("documentation").isString() != null) { form.setDocumentation(jsonObj.get("documentation").isString().stringValue()); } if (jsonObj.get("enctype").isString() != null) { form.setEnctype(jsonObj.get("enctype").isString().stringValue()); } if (jsonObj.get("lastModified").isNumber() != null) { form.setLastModified( Double.valueOf(jsonObj.get("lastModified").isNumber().doubleValue()).longValue()); } else if (jsonObj.get("lastModified").isString() != null) { form.setLastModified( Double.valueOf(jsonObj.get("lastModified").isString().stringValue()).longValue()); } if (jsonObj.get("method").isString() != null) { form.setMethod(jsonObj.get("method").isString().stringValue()); } if (jsonObj.get("name").isString() != null) { form.setName(jsonObj.get("name").isString().stringValue()); } if (jsonObj.get("taskId").isString() != null) { form.setTaskId(jsonObj.get("taskId").isString().stringValue()); } if (jsonObj.get("processName").isString() != null) { form.setProcessName(jsonObj.get("processName").isString().stringValue()); } form.setFormItems(decodeItems(jsonObj.get("formItems"))); form.setFormValidations(decodeValidations(jsonObj.get("formValidations"))); form.setInputs(decodeInputs(jsonObj.get("inputs"))); form.setOutputs(decodeOutputs(jsonObj.get("outputs"))); form.setOnLoadScripts(decodeScripts(jsonObj.get("onLoadScripts"))); form.setOnSubmitScripts(decodeScripts(jsonObj.get("onSubmitScripts"))); } return form; } @Override @SuppressWarnings("unchecked") public Map<String, List<MenuItemDescription>> decodeMenuItemsMap(String json) throws FormEncodingException { JSONObject jsonObj = JSONParser.parseLenient(json).isObject(); Map<String, Object> dataMap = asMap(jsonObj); Map<String, List<MenuItemDescription>> retval = null; if (dataMap != null) { retval = new HashMap<String, List<MenuItemDescription>>(); for (Map.Entry<String, Object> entry : dataMap.entrySet()) { List<MenuItemDescription> itemsList = new ArrayList<MenuItemDescription>(); String key = entry.getKey(); Object obj = entry.getValue(); if (obj != null) { List<Object> itemsMapList = (List<Object>) obj; for (Object itemObj : itemsMapList) { Map<String, Object> itemDescMap = (Map<String, Object>) itemObj; MenuItemDescription desc = new MenuItemDescription(); desc.setDataMap(itemDescMap); itemsList.add(desc); } } retval.put(key, itemsList); } } return retval; } @Override public FormItemRepresentation decodeItem(String json) throws FormEncodingException { JSONValue jsonValue = JSONParser.parseLenient(json); if (jsonValue.isObject() != null) { JSONObject jsonObj = jsonValue.isObject(); Map<String, Object> dataMap = asMap(jsonObj); return (FormItemRepresentation) decode(dataMap); } else { throw new FormEncodingException("Expected JSON Object: " + jsonValue); } } public Map<String, InputData> decodeInputs(JSONValue json) throws FormEncodingException { Map<String, InputData> retval = new HashMap<String, InputData>(); if (json != null && json.isObject() != null) { for (String key : json.isObject().keySet()) { JSONValue value = json.isObject().get(key); if (value.isObject() != null) { JSONObject jsonObj = value.isObject(); retval.put(key, (InputData) decode(asMap(jsonObj))); } } } return retval; } public Map<String, OutputData> decodeOutputs(JSONValue json) throws FormEncodingException { Map<String, OutputData> retval = new HashMap<String, OutputData>(); if (json != null && json.isObject() != null) { for (String key : json.isObject().keySet()) { JSONValue value = json.isObject().get(key); if (value.isObject() != null) { JSONObject jsonObj = value.isObject(); retval.put(key, (OutputData) decode(asMap(jsonObj))); } } } return retval; } public List<FBScript> decodeScripts(JSONValue json) throws FormEncodingException { List<FBScript> retval = new ArrayList<FBScript>(); if (json != null && json.isArray() != null) { JSONArray array = json.isArray(); for (int index = 0; index < array.size(); index++) { JSONValue elem = array.get(index); JSONObject jsonObj = elem.isObject(); retval.add((FBScript) decode(asMap(jsonObj))); } } return retval; } public List<FormItemRepresentation> decodeItems(JSONValue json) throws FormEncodingException { List<FormItemRepresentation> retval = new ArrayList<FormItemRepresentation>(); if (json != null && json.isArray() != null) { JSONArray array = json.isArray(); for (int index = 0; index < array.size(); index++) { JSONValue elem = array.get(index); JSONObject jsonObj = elem.isObject(); retval.add((FormItemRepresentation) decode(asMap(jsonObj))); } } return retval; } public List<FBValidation> decodeValidations(JSONValue json) throws FormEncodingException { List<FBValidation> retval = new ArrayList<FBValidation>(); if (json != null && json.isArray() != null) { JSONArray array = json.isArray(); for (int index = 0; index < array.size(); index++) { JSONValue elem = array.get(index); JSONObject jsonObj = elem.isObject(); retval.add((FBValidation) decode(asMap(jsonObj))); } } return retval; } private Map<String, Object> asMap(JSONObject jsonObj) { Map<String, Object> retval = new HashMap<String, Object>(); for (String key : jsonObj.keySet()) { JSONValue value = jsonObj.get(key); retval.put(key, fromJsonValue(value)); } return retval; } private List<Object> asList(JSONArray array) { List<Object> retval = new ArrayList<Object>(); if (array != null) { for (int index = 0; index < array.size(); index++) { retval.add(fromJsonValue(array.get(index))); } } return retval; } private Object fromJsonValue(JSONValue elem) { if (elem.isString() != null) { return elem.isString().stringValue(); } else if (elem.isNumber() != null) { return elem.isNumber().doubleValue(); } else if (elem.isArray() != null) { return asList(elem.isArray()); } else if (elem.isNull() != null) { return null; } else if (elem.isObject() != null) { return asMap(elem.isObject()); } else { return ""; } } }