解决经常变化业务逻辑

0 概述

在实际工作中由于业务是一直在不断变化中，开发工作者也要不断修改代码、测试、部署、发布。然而有时候某一块需要经常变动，这时候我们也要走前面的流程，这个时候开发效率就比较低。本文主要采用配置groovy来处理经常变化业务逻辑，当业务逻辑发生变化时候，只需要修改groovy脚本即可，这样可以极大的提高开发效率。

1 实例分析

pom 依赖

<dependencies>
    <!-- groovy -->
    <dependency>
        <groupId>org.codehaus.groovy</groupId>
        <artifactId>groovy-all</artifactId>
        <version>2.4.7</version>
    </dependency>
    <dependency>
        <groupId>com.alibaba</groupId>
        <artifactId>fastjson</artifactId>
        <version>1.2.29</version>
    </dependency>
</dependencies>

//ScriptExecutor 编译脚本和执行类

import groovy.lang.GroovyClassLoader;
import groovy.lang.Script;

import java.io.IOException;
import java.util.Map;

/**
 * Created by hsc on 17/8/6.
 */
public class ScriptExecutor {


    private static final String FUNCTION_NAME = "execute";

    private Script scriptObject;

    public Object execute(Map<String, Object> input) {
        return scriptObject.invokeMethod(FUNCTION_NAME, input);
    }
    @SuppressWarnings("unchecked")
    public synchronized boolean compile(String script, String key) {
        GroovyClassLoader loader = new GroovyClassLoader();
        try {
            //实际使用时候可以做一个缓存
            Class<Script> clazz = (Class<Script>) loader.parseClass(script, key);
            scriptObject = clazz.newInstance();
        } catch (Exception e) {
            e.printStackTrace();
            return false;
        } finally {
            try {
                loader.close();
            } catch (IOException e) {
                e.printStackTrace();
            }
        }
        return true;
    }
}

//groovy 脚本

package groovy;

import groovy.transform.CompileStatic

@CompileStatic
public def String execute(Map<String, Object> map) {
    //经常变化的逻辑 放在这里除了
    if (map != null && map.isEmpty()) {
        map.put("test", "test");
    }
    return "test";
}

2 测试

import com.alibaba.fastjson.JSON;

import java.util.HashMap;
import java.util.Map;

/**
 * Created by hsc on 17/8/6.
 */
public class Test {

    public static void main(String[] args) {

       // 这个脚本可以放在配置中心&或者DB中等
        String script = "package groovy;\n" +
                "\n" +
                "import groovy.transform.CompileStatic\n" +
                "\n" +
                "@CompileStatic\n" +
                "public def String execute(Map<String, Object> map) {\n" +
                "    if (map != null && map.isEmpty()) {\n" +
                "        map.put(\"test\", \"test\");\n" +
                "    }\n" +
                "    return \"test\";\n" +
                "}";
        Map<String,Object> map=new HashMap<String, Object>();
        ScriptExecutor scriptExecutor = new ScriptExecutor();
        if (!scriptExecutor.compile(script, "test")) {
            System.out.print("编译失败");
            return;
        }
        System.out.print(scriptExecutor.execute(map));
        System.out.print(JSON.toJSON(map));
    }
}