package com.feng.spring.chapter2.helloworld;
import junit.framework.Assert;
import org.junit.Test;
import org.springframework.expression.eva luationContext;
import org.springframework.expression.Expression;
import org.springframework.expression.ExpressionParser;
import org.springframework.expression.spel.standard.SpelExpressionParser;
import org.springframework.expression.spel.support.Standardeva luationContext;
@Test
public void helloWorld(){
ExpressionParser parser = new SpelExpressionParser();//创建解析器
Expression expression = parser.parseExpression("('Hello '+'World').concat(#end)");//解析表达式
eva luationContext context = new Standardeva luationContext();//构造上下文
context.setVariable("end", "!");
Assert.assertEquals("Hello World!", expression.getValue(context)); //求值，根据上下文获得表达式
}
}