README.md

    qlExpress相关文档

    最简单的调用案例

    <dependency>
      <groupId>com.taobao.util</groupId>
      <artifactId>taobao-express</artifactId>
      <version>3.0.17</version>
    </dependency>
    
            ExpressRunner runner = new ExpressRunner();
            DefaultContext<String, Object> context = new DefaultContext<String, Object>();
            context.put("a",1);
            context.put("b",2);
            context.put("c",3);
            String express = "a+b*c";
            Object r = runner.execute(express, context, null, true, false);
            System.out.println(r);

    更多的语法介绍

    1、java的绝大多数语法

    //支持 +,-,*,/,<,>,<=,>=,==,!=,<>【等同于!=】,%,mod【取模等同于%】,++,--,
    //in【类似sql】,like【sql语法】,&&,||,!,等操作符
    //支持for,break、continue、if then else 等标准的程序控制逻辑
    n=10;
    for(sum=0,i=0;i<n;i++){
    sum=sum+i;
    }
    return sum;
     
    
    
    //逻辑三元操作
    a=1;
    b=2;
    max = a>b?a:b;
    

    //关于对象,类,属性,方法的调用

    import com.ql.util.express.test.OrderQuery;
    //系统自动会import java.lang.*,import java.util.*;
    
    
    query = new OrderQuery();//创建class实例,会根据classLoader信息,自动补全类路径
    query.setCreateDate(new Date());//设置属性
    query.buyer = "张三";//调用属性,默认会转化为setBuyer("张三")
    result = bizOrderDAO.query(query);//调用bean对象的方法
    System.out.println(result.getId());//静态方法
     
    
    //自定义方法与调用
    function add(int a,int b){
      return a+b;
    };
    
    function sub(int a,int b){
      return a - b;
    };
    
    a=10;
    return add(a,4) + sub(a,9);
     

    2、自定义操作符号:addOperatorWithAlias+addOperator+addFunction

    
    runner.addOperatorWithAlias("如果", "if",null);
    runner.addOperatorWithAlias("则", "then",null);
    runner.addOperatorWithAlias("否则", "else",null);
    
    exp = "如果  (如果 1==2 则 false 否则 true) 则 {2+2;} 否则 {20 + 20;}";
    DefaultContext<String, Object> context = new DefaultContext<String, Object>();
    runner.execute(exp,nil,null,false,false,null);
     
    
    //定义一个继承自com.ql.util.express.Operator的操作符
    public class JoinOperator extends Operator{
    	public Object executeInner(Object[] list) throws Exception {
    		Object opdata1 = list[0];
    		Object opdata2 = list[1];
    		if(opdata1 instanceof java.util.List){
    			((java.util.List)opdata1).add(opdata2);
    			return opdata1;
    		}else{
    			java.util.List result = new java.util.ArrayList();
    			result.add(opdata1);
    			result.add(opdata2);
    			return result;				
    		}
    	}
    }
    
    ExpressRunner runner = new ExpressRunner();
    DefaultContext<String, Object> context = new DefaultContext<String, Object>();
    runner.addOperator("join",new JoinOperator());
    Object r = runner.execute("1 join 2 join 3", context, null, false, false);
    System.out.println(r);
    //返回结果  [1, 2, 3]
     
    
    class GroupOperator extends Operator {
    	public GroupOperator(String aName) {
    		this.name= aName;
    	}
    	public Object executeInner(Object[] list)throws Exception {
    		Object result = Integer.valueOf(0);
    		for (int i = 0; i < list.length; i++) {
    			result = OperatorOfNumber.add(result, list[i],false);//根据list[i]类型(string,number等)做加法
    		}
    		return result;
    	}
    }
    
    runner.addFunction("group", new GroupOperator("group"));
    ExpressRunner runner = new ExpressRunner();
    DefaultContext<String, Object> context = new DefaultContext<String, Object>();
    runner.addOperator("join",new JoinOperator());
    Object r = runner.execute("group(1,2,3)", context, null, false, false);
    System.out.println(r);
    //返回结果  6
    

    3、类的静态方法,对象的方法绑定:addFunctionOfClassMethod+addFunctionOfServiceMethod

    
    public class BeanExample {
    	public static String upper(String abc) {
    		return abc.toUpperCase();
    	}
    	public boolean anyContains(String str, String searchStr) {
    
            char[] s = str.toCharArray();
            for (char c : s) {
                if (searchStr.contains(c+"")) {
                    return true;
                }
            }
            return false;
        }
    }
    
    runner.addFunctionOfClassMethod("取绝对值", Math.class.getName(), "abs",
    				new String[] { "double" }, null);
    runner.addFunctionOfClassMethod("转换为大写", BeanExample.class.getName(),
    				"upper", new String[] { "String" }, null);
    
    runner.addFunctionOfServiceMethod("打印", System.out, "println",new String[] { "String" }, null);
    runner.addFunctionOfServiceMethod("contains", new BeanExample(), "anyContains",
                new Class[] { String.class, String.class }, null);
    
    String exp = “取绝对值(-100);转换为大写(\"hello world\");打印(\"你好吗?\");contains("helloworld",\"aeiou\")”;
    runner.execute(exp, context, null, false, false);
    

    4、macro 宏定义

    runner.addMacro("计算平均成绩", "(语文+数学+英语)/3.0");
    runner.addMacro("是否优秀", "计算平均成绩>90");
    IExpressContext<String, Object> context =new DefaultContext<String, Object>();
    context.put("语文", 88);
    context.put("数学", 99);
    context.put("英语", 95);
    Object result = runner.execute("是否优秀", context, null, false, false);
    System.out.println(r);
    //返回结果true
    

    5、编译脚本,查询外部需要定义的变量,注意以下脚本int和没有int的区别

    String express = "int 平均分 = (语文+数学+英语+综合考试.科目2)/4.0;return 平均分";
    ExpressRunner runner = new ExpressRunner(true,true);
    String[] names = runner.getOutVarNames(express);
    for(String s:names){
     System.out.println("var : " + s);
    }
    
    //输出结果:
    
    var : 数学
    var : 综合考试
    var : 英语
    var : 语文

    6、关于不定参数的使用

        @Test
        public void testMethodReplace() throws Exception {
            ExpressRunner runner = new ExpressRunner();
            IExpressContext<String,Object> expressContext = new DefaultContext<String,Object>();
            runner.addFunctionOfServiceMethod("getTemplate", this, "getTemplate", new Class[]{Object[].class}, null);
    
            //(1)默认的不定参数可以使用数组来代替
            Object r = runner.execute("getTemplate([11,'22',33L,true])", expressContext, null,false, false);
            System.out.println(r);
            //(2)像java一样,支持函数动态参数调用,需要打开以下全局开关,否则以下调用会失败
            DynamicParamsUtil.supportDynamicParams = true;
            r = runner.execute("getTemplate(11,'22',33L,true)", expressContext, null,false, false);
            System.out.println(r);
        }
        //等价于getTemplate(Object[] params)
        public Object getTemplate(Object... params) throws Exception{
            String result = "";
            for(Object obj:params){
                result = result+obj+",";
            }
            return result;
        }

    7、关于集合的快捷写法

        @Test
        public void testSet() throws Exception {
            ExpressRunner runner = new ExpressRunner(false,false);
            DefaultContext<String, Object> context = new DefaultContext<String, Object>();
            String express = "abc = NewMap(1:1,2:2); return abc.get(1) + abc.get(2);";
            Object r = runner.execute(express, context, null, false, false);
            System.out.println(r);
            express = "abc = NewList(1,2,3); return abc.get(1)+abc.get(2)";
            r = runner.execute(express, context, null, false, false);
            System.out.println(r);
            express = "abc = [1,2,3]; return abc[1]+abc[2];";
            r = runner.execute(express, context, null, false, false);
            System.out.println(r);
        }
    

    项目简介

    🚀 Github 镜像仓库 🚀

    源项目地址

    https://github.com/alibaba/qlexpress

    发行版本

    当前项目没有发行版本

    贡献者 4

    B baoxingjie @baoxingjie
    Q qiao tian @qiao tian
    T The Gitter Badger @The Gitter Badger
    A Alibaba OSS @Alibaba OSS

    开发语言

    • Java 99.3 %
    • CodeQL 0.7 %