DynaBeanHolder动态bean构造器实现

转载请注明出处：https://blog.csdn.net/jevonsCSDN/article/details/87824271 【Jevons’Blog】

依赖包：

commons-logging.jar

commons-beanutils-1.8.0-BETA.jar

cglib-nodep-3.2.10.jar

辅助包：

fastjson-1.1.39.jar

优化复制方法 2019-2-25 18:04:08

package dynamic;import java.beans.PropertyDescriptor;
import java.lang.reflect.InvocationTargetException;
import java.util.HashMap;
import java.util.Iterator;
import java.util.Map;
import java.util.Set;import net.sf.cglib.beans.BeanGenerator;
import net.sf.cglib.beans.BeanMap;import org.apache.commons.beanutils.BeanUtils;
import org.apache.commons.beanutils.BeanUtilsBean;import com.alibaba.fastjson.JSON;public class DynaBeanHolder {@SuppressWarnings("rawtypes")private Map classMap = new HashMap<String, Class<?>>();@SuppressWarnings("rawtypes")private Map valueMap = new HashMap<String, Object>();/** 创建标志 */private boolean isCreate = false;private BeanGenerator generator = null;private static BeanUtilsBean beanUtilsBean = BeanUtilsBean.getInstance();private Object dynaBean = null;private BeanMap beanMap = null;public DynaBeanHolder() {super();}/*** 初始化属性 class、key、value* * @param key* @param value* @return*/@SuppressWarnings("unchecked")private DynaBeanHolder initSet(String key, Object value) {if (this.dynaBean == null || !this.classMap.containsKey(key)) {this.classMap.put(key, value.getClass());this.valueMap.put(key, value);} else {beanMap.put(key, value);}return this;}/*** 初始化属性 class、key,同时值为null* * @param key* @param value* @return*/@SuppressWarnings("unchecked")public DynaBeanHolder setToNull(String key, Class<?> clazz) {if (this.dynaBean == null || !this.classMap.containsKey(key)) {this.classMap.put(key, clazz);this.valueMap.put(key, null);} else {beanMap.put(key, null);}return this;}/*** 给指定的dynaBean赋值* * @param dynaBean* @param key* @param value* @return*/public static Object set(Object dynaBean, String key, Object value) {BeanMap.create(dynaBean).put(key, value);return dynaBean;}/*** set方法* * @param key*            属性名* @param value*            值*/public DynaBeanHolder set(String key, Object value) {return initSet(key, value);}/*** get方法* * @param key*            属性名* @return 值*/public Object get(String key) {return beanMap.get(key);}/*** 获取bean（含有完整的属性 set/get方法）* * @return*/public Object getDynaBean() {return this.dynaBean;}/*** 结束属性初始化，创建并返回一个Object对象（内含相应属性的set/get方法）* * @return*/public DynaBeanHolder create() {if (!isCreate) {generator = new BeanGenerator();BeanGenerator.addProperties(generator, this.classMap);this.dynaBean = generator.create();this.beanMap = BeanMap.create(this.dynaBean);this.beanMap.putAll(this.valueMap);this.isCreate = true;}return this;}/*** 重建* * @return*/public DynaBeanHolder reCreate() {this.isCreate = false;return create();}/*** 销毁*/public void destroy() {this.classMap.clear();this.valueMap.clear();this.generator = null;this.dynaBean = null;this.beanMap = null;this.isCreate = false;}/*** 从dynaBean复制属性到target* * @param target* @throws IllegalAccessException* @throws InvocationTargetException*/public void copyTo(Object target) throws IllegalAccessException,InvocationTargetException {BeanUtils.copyProperties(target, this.dynaBean);}/*** 特殊复制：从dynaBean复制属性到target* * @param target* @param copyProperty* @throws Exception*/public void copySpecialTo(Object target, Collection<String> copyProperty)throws Exception {boolean specialCopy = copyProperty == null ? false : true;if (specialCopy) {for (Iterator it = copyProperty.iterator(); it.hasNext();) {String key = (String) it.next();BeanUtils.copyProperty(target, key,BeanUtils.getProperty(this.dynaBean, key));}} else {copyTo(target);}}/*** 从target复制属性到dynaBean* * @param src* @throws Exception*/public DynaBeanHolder copyFrom(Object src) throws Exception {return copyFrom(src, false);}public DynaBeanHolder copyFrom(Object src, boolean asNew) throws Exception {return copySpecialFrom(src, null, asNew);}/*** 从target复制属性到dynaBean* * @param src* @param asNew*            是否复制为一个新的DynaBeanHolder* @return* @throws Exception*/@SuppressWarnings("unchecked")public DynaBeanHolder copySpecialFrom(Object src,Collection<String> copyProperty, boolean asNew) throws Exception {boolean specialCopy = false;int copySize = 0;if (copyProperty != null) {specialCopy = true;copySize = copyProperty.size();}if (asNew) {DynaBeanHolder newHolder = newInstance();PropertyDescriptor[] descriptors = getPropertyDescriptor(src);for (PropertyDescriptor descriptor : descriptors) {if (!descriptor.getName().equals("class")&& ((specialCopy && copyProperty.contains(descriptor.getName())) || (!specialCopy))) {Class<?> clazz = descriptor.getPropertyType();String key = descriptor.getName();newHolder.classMap.put(key, clazz);newHolder.valueMap.put(key, descriptor.getReadMethod().invoke(src));if (specialCopy && --copySize == 0)break;// 阻断多余循环}}return newHolder.create();} else {if (this.dynaBean != null) {if (specialCopy) {PropertyDescriptor[] descriptors = getPropertyDescriptor(src);for (PropertyDescriptor descriptor : descriptors) {if (!descriptor.getName().equals("class")&& copyProperty.contains(descriptor.getName())) {String key = descriptor.getName();BeanUtils.copyProperty(this.dynaBean, key,BeanUtils.getProperty(src, key));if (--copySize == 0)break;}}} else {BeanUtils.copyProperties(this.dynaBean, src);}return this;} else {throw new Exception("Please initialize the dynaBean before calling the copyFrom!");}}}/*** 特殊复制属性 （只复制指定属性名的值） 静态* * @param src* @param copyProperty* @return* @throws Exception*/public static DynaBeanHolder copysSpecFrom(Object src,Collection<String> copyProperty) throws Exception {return newInstance().copySpecialFrom(src, copyProperty, true);}/*** 特殊复制属性 （只复制指定属性名的值） 静态* * @param src* @param copyProperty* @return* @throws Exception*/public static DynaBeanHolder copysSpecFrom(Object src,String... copyProperty) throws Exception {List<String> propertyList = null;if (copyProperty != null) {propertyList = Arrays.asList(copyProperty);} else {propertyList = Collections.emptyList();}return newInstance().copySpecialFrom(src, propertyList, true);}/*** 复制属性 （只复制指定属性名的值） 静态* * @param src* @param copyProperty* @return* @throws Exception*/public static DynaBeanHolder copysFrom(Object src) throws Exception {return newInstance().copyFrom(src, true);}/*** 获取属性 <br>* PropertyUtilsBean中已使用FastHashMap.setFast(true) <br>* 针对PropertyDescriptor做了缓存处理，不需要担心重复获取影响效率问题（线程安全）* * @param bean* @return*/public static PropertyDescriptor[] getPropertyDescriptor(Object bean) {return beanUtilsBean.getPropertyUtils().getPropertyDescriptors(bean);}public static DynaBeanHolder newInstance() {return new DynaBeanHolder();}/*** 特殊复制属性 （只复制指定属性名的值）* * @param src* @param copyProperty* @return* @throws Exception*/public DynaBeanHolder copySpecialFrom(Object src,Collection<String> copyProperty) throws Exception {return copySpecialFrom(src, copyProperty, false);}/*** 获取BeanMap* * @return*/public BeanMap getBeanMap() {if (this.beanMap == null && this.dynaBean != null) {this.beanMap = BeanMap.create(this.dynaBean);} else if (this.beanMap != null && this.dynaBean == null) {this.beanMap = null;}return this.beanMap;}@Overridepublic int hashCode() {final int prime = 31;int result = 1;result = prime * result + ((beanMap == null) ? 0 : beanMap.hashCode());return result;}@Overridepublic boolean equals(Object obj) {if (this == obj)return true;if (obj == null)return false;if (getClass() != obj.getClass())return false;DynaBeanHolder other = (DynaBeanHolder) obj;if (beanMap == null) {if (other.beanMap != null)return false;} else if (!beanMap.equals(other.beanMap))return false;return true;}public static void main(String[] args) throws Exception {//测试样例：动态bean赋值给 user对象DynaBeanHolder bean = new DynaBeanHolder();Object object = bean.set("name","来了").set("age", 24).create();User user1 = new User();BeanUtils.copyProperties(user1, object);BeanUtils.copyProperties(user1, bean.getBeanMap());System.out.println(JSON.toJSON(object));System.out.println(JSON.toJSON(bean.set("fuck", "??").reCreate()));//测试样例：user对象赋值给 动态beanDynaBeanHolder bean2 = new DynaBeanHolder();Object object2 = bean2.setToNull("name", String.class).setToNull("age", Integer.class).create();User user2 = new User();user2.setAge(12);user2.setName("张三");bean2.copyFrom(user2);//正确赋值
//      BeanUtils.copyProperties(object2, user2);//正确赋值
//      BeanUtils.copyProperties(bean2.getBeanMap(),user2);//错误赋值
//      BeanUtils.copyProperties(bean2,user2);//错误赋值//测试样例：动态bean3 与 动态bean4比较DynaBeanHolder bean3 = new DynaBeanHolder();Object object3 = bean3.initSet("name","来了").initSet("age", 24).create();DynaBeanHolder bean4 = new DynaBeanHolder();Object object4 = bean4.initSet("name","来了").initSet("age", 24).create();System.out.println(object3.equals(object4));//falseSystem.out.println(object3==object4);//falseSystem.out.println(bean3.equals(bean4));//trueSystem.out.println(bean3==bean4);//falseSystem.out.println(bean3.getBeanMap().equals(bean4.getBeanMap()));//trueSystem.out.println(bean3.getBeanMap()==bean4.getBeanMap());//falseDynaBeanHolder bean5 = new DynaBeanHolder();bean5.copyFrom(user2,true);System.out.println(JSON.toJSON(bean5));}
}

实体测试类：

package dynamic;public class User {private String name;private Integer age;public String getName() {return name;}public void setName(String name) {this.name = name;}public Integer getAge() {return age;}public void setAge(Integer age) {this.age = age;}}

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