java 将字符串转化为可执行的代码

jar包依赖

<dependency> <groupId>org.apache.commons</groupId> <artifactId>commons-jexl</artifactId> <version>2.1.1</version> </dependency>

package com.yousong.common;
import java.util.HashMap;
import java.util.Map;

import org.apache.commons.jexl2.Expression;
import org.apache.commons.jexl2.JexlContext;
import org.apache.commons.jexl2.JexlEngine;
import org.apache.commons.jexl2.MapContext;
 
/**
 * 动态加载方法
 * @author ld
 *
 */
public class DyMethodUtil {
	
	public static Object invokeMethod(String jexlExp,Map<String,Object> map){
		JexlEngine jexl=new JexlEngine();
		Expression e = jexl.createExpression(jexlExp);
		JexlContext jc = new MapContext();
		for(String key:map.keySet()){
			jc.set(key, map.get(key));
		}
		if(null==e.evaluate(jc)){
			return "";
		}
		return e.evaluate(jc);
	}
  public static void main(String[] args) {
	  Map<String,Object> map=new HashMap<String,Object>(); 
       map.put("money",2100);  
		String expression="money>=4000";  
		Object code = invokeMethod(expression,map); 
	    System.err.println(code);
}
}

上面的代码很详细了，可以直接执行的demo。拿走不谢