High performance Java reflection Kit ReflectASM

ReflectASM  use bytecode generated achieved more efficient reflection. Generates an access classes is performed to set / get field access methods or create the instance. ASM saw can be realized by way ReflectASM byte code generation, rather than relying on Java reflection mechanism itself to achieve, so that it is faster, and avoids the problem of access to the original type generated by automatic packing .

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pom.xml

<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
    xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
    <modelVersion>4.0.0</modelVersion>

    <groupId>com.jts</groupId>
    <artifactId>t1</artifactId>
    <version>0.0.1-SNAPSHOT</version>
    <packaging>jar</packaging>

    <properties>
        <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
    </properties>

    <dependencies>
        <dependency>
            <groupId>junit</groupId>
            <artifactId>junit</artifactId>
            <version>4.10</version>
            <scope>test</scope>
        </dependency>
        <dependency>
            <groupId>com.esotericsoftware</groupId>
            <artifactId>reflectasm</artifactId>
            <version>1.11.0</version>
        </dependency>
    </dependencies>
</project>

Be reflected classes:

package com.jts.service;

public class UserService {
    
    public int state;
    
    public void update(int id, String username) {
        
    }
}

Test categories:

package com.jts.test;

import java.lang.reflect.Method;

import org.junit.Test;

import com.esotericsoftware.reflectasm.ConstructorAccess;
import com.esotericsoftware.reflectasm.FieldAccess;
import com.esotericsoftware.reflectasm.MethodAccess;
import com.jts.service.UserService;

public class AppTest {
    
    public static void main(String[] args) throws Exception{
        AppTest test = new AppTest();
        test.testJdkReflect();
        test.testReflectAsm4Name();
        test.testReflectAsm4Index();
    }
    
    /**
     * JDK反射调用方法
     * @throws Exception
     */
    @Test
    public void testJdkReflect() throws Exception {
        UserService target = new UserService();
        long start = System.currentTimeMillis();
        Method method = target.getClass().getMethod("update", int.class, String.class);
        for (int i = 0; i < 100000000; i++) {
            method.invoke(target, 1, "zhangsan");
        }
        long end = System.currentTimeMillis();
        System.out.println("timeout=" + (end - start));//809 753 880 875 816 
    }

    /**
     * ReflectAsm反射调用方法
     * 用名称定位反射方法
     */
    @Test
    public void testReflectAsm4Name() {
        UserService target = new UserService();
        MethodAccess access = MethodAccess.get(UserService.class);//生成字节码的方式创建UserServiceMethodAccess
        long start = System.currentTimeMillis();
        for (int i = 0; i < 100000000; i++) {
            access.invoke(target, "update", 1, "zhangsan");
        }
        long end = System.currentTimeMillis();
        System.out.println("timeout=" + (end - start));//523 382 415 489 482
    }

    /**
     * ReflectAsm反射调用方法
     * 用方法和字段的索引定位反射方法，性能高
     */
    @Test
    public void testReflectAsm4Index() {
        UserService target = new UserService();
        MethodAccess access = MethodAccess.get(UserService.class);
        int index = access.getIndex("update", int.class, String.class);
        long start = System.currentTimeMillis();
        for (int i = 0; i < 100000000; i++) {
            access.invoke(target, index, 1, "zhangsan");
        }
        long end = System.currentTimeMillis();
        System.out.println("timeout=" + (end - start));//12 15 23 14 24
    }

    /**
     * ReflectAsm反射来set/get字段值
     */
    @Test
    public void testFieldAccess() {
        UserService target = new UserService();
        FieldAccess fieldAccess = FieldAccess.get(target.getClass());
        fieldAccess.set(target, "state", 1);
        int state = (Integer)fieldAccess.get(target, "state");
        System.out.println(state);
        
    }

    /**
     * ReflectAsm反射来调用构造方法
     */
    @Test
    public void testConstructorAccess() {
        ConstructorAccess<UserService> constructorAccess = ConstructorAccess.get(UserService.class);
        UserService userService = constructorAccess.newInstance();
        System.out.println(userService);
    }

    /**
     * 查找方法的索引
     */
    @Test
    public void testIndex() {
        UserService target = new UserService();
        MethodAccess methodAccess = MethodAccess.get(target.getClass());
        int index = methodAccess.getIndex("update", int.class, String.class);
        System.out.println(index);
    }

}