QLExpress-第一个helloworld

maven中央仓库依赖：

<dependency>
  <groupId>com.alibaba</groupId>
  <artifactId>QLExpress</artifactId>
  <version>3.2.0</version>
</dependency>

helloworld

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);