struts2-json-plugin源码

package com.googlecode.jsonplugin; import com.googlecode.jsonplugin.annotations.JSON; import org.apache.commons.logging.Log; import org.apache.commons.logging.LogFactory; import java.beans.BeanInfo; import java.beans.IntrospectionException; import java.beans.Introspector; import java.beans.PropertyDescriptor; import java.lang.reflect.Array; import java.lang.reflect.InvocationTargetException; import java.lang.reflect.Method; import java.lang.reflect.Modifier; import java.lang.reflect.ParameterizedType; import java.lang.reflect.Type; import java.text.DateFormat; import java.text.ParseException; import java.text.SimpleDateFormat; import java.util.ArrayList; import java.util.Collection; import java.util.Date; import java.util.HashMap; import java.util.HashSet; import java.util.Iterator; import java.util.List; import java.util.Locale; import java.util.Map; import java.util.Set; import java.math.BigDecimal; import java.math.BigInteger; /** * Isolate the process of populating JSON objects from the Interceptor class itself. */ public class JSONPopulator { private static final Log log = LogFactory.getLog(JSONPopulator.class); private String dateFormat = JSONUtil.RFC3339_FORMAT; public JSONPopulator() { } public JSONPopulator(String dateFormat) { this.dateFormat = dateFormat; } public String getDateFormat() { return dateFormat; } public void setDateFormat(String dateFormat) { this.dateFormat = dateFormat; } @SuppressWarnings("unchecked") public void populateObject(Object object, final Map elements) throws IllegalAccessException, InvocationTargetException, NoSuchMethodException, IntrospectionException, IllegalArgumentException, JSONException, InstantiationException { Class clazz = object.getClass(); BeanInfo info = Introspector.getBeanInfo(clazz); PropertyDescriptor[] props = info.getPropertyDescriptors(); //iterate over class fields for (int i = 0; i < props.length; ++i) { PropertyDescriptor prop = props[i]; String name = prop.getName(); if (elements.containsKey(name)) { Object value = elements.get(name); Method method = prop.getWriteMethod(); if (method != null) { JSON json = method.getAnnotation(JSON.class); if ((json != null) && !json.deserialize()) { continue; } //use only public setters if (Modifier.isPublic(method.getModifiers())) { Class[] paramTypes = method.getParameterTypes(); Type[] genericTypes = method.getGenericParameterTypes(); if (paramTypes.length == 1) { Object convertedValue = this.convert(paramTypes[0], genericTypes[0], value, method); method.invoke(object, new Object[]{convertedValue}); } } } } } } @SuppressWarnings("unchecked") public Object convert(Class clazz, Type type, Object value, Method method) throws IllegalArgumentException, JSONException, IllegalAccessException, InvocationTargetException, InstantiationException, NoSuchMethodException, IntrospectionException { if (value == null) { //if it is a java primitive then get a default value, otherwise leave it as null return clazz.isPrimitive() ? convertPrimitive(clazz, value, method) : null; } else if (isJSONPrimitive(clazz)) return convertPrimitive(clazz, value, method); else if (Collection.class.isAssignableFrom(clazz)) return convertToCollection(clazz, type, value, method); else if (Map.class.isAssignableFrom(clazz)) return convertToMap(clazz, type, value, method); else if (clazz.isArray()) return convertToArray(clazz, type, value, method); else if (value instanceof Map) { // nested bean Object convertedValue = clazz.newInstance(); this.populateObject(convertedValue, (Map) value); return convertedValue; } else if (BigDecimal.class.equals(clazz)) { return new BigDecimal(value != null ? value.toString() : "0"); } else if (BigInteger.class.equals(clazz)) { return new BigInteger(value != null ? value.toString() : "0"); } else throw new JSONException("Incompatible types for property " + method.getName()); } private static boolean isJSONPrimitive(Class clazz) { return clazz.isPrimitive() || clazz.equals(String.class) || clazz.equals(Date.class) || clazz.equals(Boolean.class) || clazz.equals(Byte.class) || clazz.equals(Character.class) || clazz.equals(Double.class) || clazz.equals(Float.class) || clazz.equals(Integer.class) || clazz.equals(Long.class) || clazz.equals(Short.class) || clazz.equals(Locale.class) || clazz.isEnum(); } @SuppressWarnings("unchecked") private Object convertToArray(Class clazz, Type type, Object value, Method accessor) throws JSONException, IllegalArgumentException, IllegalAccessException, InvocationTargetException, InstantiationException, NoSuchMethodException, IntrospectionException { if (value == null) return null; else if (value instanceof List) { Class arrayType = clazz.getComponentType(); List values = (List) value; Object newArray = Array.newInstance(arrayType, values.size()); //create an object for each element for (int j = 0; j < values.size(); j++) { Object listValue = values.get(j); if (arrayType.equals(Object.class)) { //Object[] Array.set(newArray, j, listValue); } else if (isJSONPrimitive(arrayType)) { //primitive array Array.set(newArray, j, this.convertPrimitive(arrayType, listValue, accessor)); } else if (listValue instanceof Map) { //array of other class Object newObject = null; if (Map.class.isAssignableFrom(arrayType)) { newObject = convertToMap(arrayType, type, listValue, accessor); } else if (List.class.isAssignableFrom(arrayType)) { newObject = convertToCollection(arrayType, type, listValue, accessor); } else { newObject = arrayType.newInstance(); this.populateObject(newObject, (Map) listValue); } Array.set(newArray, j, newObject); } else throw new JSONException("Incompatible types for property " + accessor.getName()); } return newArray; } else throw new JSONException("Incompatible types for property " + accessor.getName()); } @SuppressWarnings("unchecked") private Object convertToCollection(Class clazz, Type type, Object value, Method accessor) throws JSONException, IllegalArgumentException, IllegalAccessException, InvocationTargetException, InstantiationException, NoSuchMethodException, IntrospectionException { if (value == null) return null;