java通过cglib动态生成实体bean的操作

< dependency >

       < groupId >commons-beanutils</ groupId >

       < artifactId >commons-beanutils</ artifactId >

       < version >1.9.3</ version >

     </ dependency >

     < dependency >

       < groupId >cglib</ groupId >

       < artifactId >cglib-nodep</ artifactId >

       < version >3.2.4</ version >

     </ dependency >

package com.dym.entity;

import net.sf.cglib.beans.BeanGenerator;

import org.apache测试数据mons.collections.map.MultiValueMap;

import java.lang.reflect.*;

import java.util.ArrayList;

import java.util.HashMap;

import java.util.Iterator;

import java.util.Map;

/**

  * @author: zhaoxu

  * @description:

  */

public class DynamicBeanEntity {

   Object dynamicBean;

   Class clazz;

   public DynamicBeanEntity(Map dynAttrMap) {

     this .dynamicBean = generateBean(dynAttrMap);

     clazz = dynamicBean.getClass();

   }

   /**

    * 获取所有属性值

    *

    * @return

    * @throws IllegalAccessException

    */

   public Map<String, Object> getValues() throws IllegalAccessException {

     Map<String, Object> fieldValuesMap = new HashMap( 16 );

     Field[] fields = clazz.getDeclaredFields();

     for (Field field : fields) {

       field.setAccessible( true );

       Object fieldValue = field.get(dynamicBean);

       fieldValuesMap.put(field.getName().split( "\\$cglib_prop_" )[ 1 ], fieldValue);

     }

     return fieldValuesMap;

   }

   /**

    * 获取动态bean所有方法信息

    *

    * @return

    */

   public MultiValueMap getMethods() {

     MultiValueMap map = new MultiValueMap();

     Method[] methods = clazz.getMethods();

     for (Method method : methods) {

       Type[] genericParameterTypes = method.getGenericParameterTypes();

       if (genericParameterTypes.length > 0 ) {

         for (Type type : genericParameterTypes) {

           map.put(method.getName(), type);

         }

       } else {

         map.put(method.getName(), null );

       }

     }

     return map;

   }

   /**

    * 执行某个方法

    *

    * @param methodName

    * @param parameters

    * @return

    * @throws InvocationTargetException

    * @throws IllegalAccessException

    * @throws NoSuchMethodException

    */

   public Object executeMethod(String methodName, Object... parameters) throws InvocationTargetException, IllegalAccessException, NoSuchMethodException {

     ArrayList<Class> paramTypeList = new ArrayList();

     for (Object paramType : parameters) {

       paramTypeList.add(paramType.getClass());

     }

     Class[] classArray = new Class[paramTypeList.size()];

     Method method = clazz.getMethod(methodName, paramTypeList.toArray(classArray));

     Object invoke = method.invoke(dynamicBean, parameters);

     return invoke;

   }

   /**

    * 设置属性值

    *

    * @param property

    * @param value

    * @throws NoSuchFieldException

    * @throws IllegalAccessException

    */

   public void setValue(String property, Object value) throws NoSuchFieldException, IllegalAccessException {

     Field declaredField = clazz.getDeclaredField( "$cglib_prop_" + property);

     declaredField.setAccessible( true );

     declaredField.set(dynamicBean, value);

   }

   /**

    * 获取属性值

    *

    * @param property

    * @return

    * @throws NoSuchFieldException

    * @throws IllegalAccessException

    */

   public Object getValue(String property) throws NoSuchFieldException, IllegalAccessException {

     Field declaredField = clazz.getDeclaredField( "$cglib_prop_" + property);

     declaredField.setAccessible( true );

     Object value = declaredField.get(dynamicBean);

     return value;

   }

   public Object getEntity() {

     return this .dynamicBean;

   }

   /**

    * 利用cglib的BeanGenerator创建对象

    *

    * @param dynAttrMap

    * @return

    */

   private Object generateBean(Map dynAttrMap) {

     BeanGenerator generator = new BeanGenerator();

     Iterator iterator = dynAttrMap.keySet().iterator();

     while (iterator.hasNext()) {

       String key = iterator.next().toString();

       generator.addProperty(key, (Class) dynAttrMap.get(key));

     }

     return generator.create();

   }

}

package com.dym.attr;

import com.dym.entity.DynamicBeanEntity;

import org.apache测试数据mons.collections.map.MultiValueMap;

import java.lang.reflect.InvocationTargetException;

import java.util.HashMap;

import java.util.Map;

/**

  * @author: zhaoxu

  * @description:

  */

public class test {

   public static void main(String[] args) throws NoSuchFieldException, IllegalAccessException, NoSuchMethodException, InvocationTargetException {

     // 设置属性们，默认16

     HashMap propertyMap = new HashMap( 16 );

     propertyMap.put( "name" , String. class );

     propertyMap.put( "age" , Integer. class );

     propertyMap.put( "height" , Double. class );

     // 生成动态 Entity

     DynamicBeanEntity bean = new DynamicBeanEntity(propertyMap);

     //设置属性值

     bean.setValue( "name" , "zx" );

     bean.setValue( "age" , 22 );

     bean.setValue( "height" , 175.0 );

     //获取属性值

     Map<String, Object> values = bean.getValues();

     //获取可执行的方法

     MultiValueMap methods = bean.getMethods();

     //执行某个方法

     bean.executeMethod( "setAge" , 23 );

     System.out.println( "动态bean的age属性：" +bean.getValue( "age" ));

   }

}

package com.dym.test;

import com.dym.util.DBUtil;

import com.dym.util.DynmicEntity;

import org.springframework.stereotype.Component;

import java.sql.Connection;

import java.sql.PreparedStatement;

import java.sql.ResultSet;

import java.sql.SQLException;

import java.util.ArrayList;

import java.util.HashMap;

import java.util.Map;

/**

  * @author: zhaoxu

  * @description:

  */

@Component

public class test {

   public static void main(String[] args) {

     ArrayList<DynmicEntity> beans = new ArrayList<>();

     Connection conn = null ;

     PreparedStatement prst = null ;

     String sql = "" ;

     sql = "select table_name from information_schema.tables where table_schema=\'public\'" ;

     conn = DBUtil.getConn();

     try {

       prst = conn.prepareStatement(sql);

       ResultSet rs = prst.executeQuery();

       while (rs.next()) {

         String tableName = rs.getString( 1 );

         Map attrMap = new HashMap<>();

         String findFieldSql = "SELECT format_type(a.atttypid,a.atttypmod) as type,a.attname as name, a.attnotnull as notnull  \n" +

             "FROM pg_class as c,pg_attribute as a where c.relname = \'" + tableName + "\' and a.attrelid = c.oid and a.attnum>0" ;

         PreparedStatement fieldsPrst = conn.prepareStatement(findFieldSql);

         ResultSet fieldsRs = fieldsPrst.executeQuery();

         while (fieldsRs.next()) {

           String fieldType = fieldsRs.getString( 1 );

           String fieldName = fieldsRs.getString( 2 );

           attrMap.put(fieldName, Object. class );

         }

         DynmicEntity bean = new DynmicEntity(attrMap);

         beans.add(bean);

       }

     } catch (SQLException e) {

       e.printStackTrace();

     }

     DBUtil.close(prst, conn);

   }

}

package com.dym.util;

import java.sql.Connection;

import java.sql.DriverManager;

import java.sql.PreparedStatement;

import java.sql.ResultSet;

import java.sql.SQLException;

/**

  * @author: zhaoxu

  * @description:

  */

public class DBUtil {

   private final static String URL= "jdbc:postgresql://localhost:5432/dynmic" ;

   private final static String NAME= "postgres" ;

   private final static String PASS= "123456" ;

   private static Connection conn= null ;

   /**

    *

    *@Title:DBUtil

    *@Description:

    */

   public DBUtil(){

   }

   /**

    *

    * @Tiltle getConn

    * @return Connection

    * @Description:返回连接

    */

   public static Connection getConn(){

     //告诉jvm使用mysql

     try {

       //加载驱动，string为驱动名字

       Class.forName( "org.postgresql.Driver" );

       //连接数据库，得到Connection连接

       conn=DriverManager.getConnection(URL,NAME,PASS);

       //System.out.println("连接数据库： "+conn);

     } catch (ClassNotFoundException e) {

       // TODO Auto-generated catch block

       e.printStackTrace();

     } catch (SQLException e){

       e.printStackTrace();

     }

     return conn;

   }

   //关闭结果对象集

   public static void close(ResultSet rs){

     if (rs!= null ){

       try {

         rs.close();

       } catch (SQLException e){

         e.printStackTrace();

       }

     }

   }

   //关闭编译语句对象

   public static void close(PreparedStatement prst){

     if (prst!= null ){

       try {

         prst.close();

       } catch (SQLException e){

         e.printStackTrace();

       }

     }

   }

   //关闭结果对象集

   public static void close(Connection conn){

     if (conn!= null ){

       try {

         conn.close();

       } catch (SQLException e){

         e.printStackTrace();

       }

     }

   }

   //对于更新操作关闭资源

   public static void close(PreparedStatement prst,Connection conn){

     close(prst);

     close(conn);

   }

   //关闭所有

   public static void close(ResultSet rs,PreparedStatement prst,Connection conn){

     close(rs);

     close(prst);

     close(conn);

   }

}

package test.refect;

public class Student {

     // 姓名

     private String name;

     // 年龄

     private String age;

     // 住址

     private String address;

     public String getName() {

         return name;

     }

     public void setName(String name) {

         this .name = name;

     }

     public String getAge() {

         return age;

     }

     public void setAge(String age) {

         this .age = age;

     }

     public String getAddress() {

         return address;

     }

     public void setAddress(String address) {

         this .address = address;

     }

     @Override

     public String toString() {

         return "Student [name=" + name + ", age=" + age + ", address=" + address + "]" ;

     }

     public void sayHello(Book book){

         System.out.println(book.getName());    

     }

}

package test.refect;

public class Book {

     private String name;

     public String getName() {

         return name;

     }

     public void setName(String name) {

         this .name = name;

     }  

}

package test.refect;

import java.lang.reflect.Field;

import java.lang.reflect.Method;

import java.net.URLDecoder;

import java.util.Iterator;

import net.sf.json.JSONObject;

public class Main {

     public static void main(String[] args) throws Exception {

         //Student str --> Student 主类

         String str = "test.refect.Student" ;

         Class<?> clazz = Class.forName(str);

         //Book实体 str --> Book 参数类

         String bookStr = "test.refect.Book" ;

         Class<?> bookClazz = Class.forName(bookStr);     

         //json --> Book    将参数类转为JSONOBJECT

         String bookJson = "{\"name\":\"Java\"}" ;

         JSONObject jsonObject=JSONObject.fromObject(bookJson);

         //实例化参数类

         Object bookInStance = bookClazz.newInstance();

         // 通过JSONOBJECT 为参数类赋值

         Iterator<?> keys = jsonObject.keys();

     while (keys.hasNext()) {

       Object key = keys.next();

       Object value = jsonObject.get(key);

       // 替换非法字符

       String _key = String.valueOf(key).replaceFirst( "\\W" , "" );

       Field field = bookClazz.getDeclaredField(_key);

       field.setAccessible( true );

       field.set(bookInStance, URLDecoder.decode(String.valueOf(value), "UTF-8" ));

       field.setAccessible( false );

     }

     //将参数类注入到主类

     Method method = clazz.getDeclaredMethod( "sayHello" , bookClazz);

     //执行主类

     method.invoke(clazz.newInstance(), bookInStance);      

     }

}