我是 Java、Spring 和 SpEL 新手,我无法使这个简单的代码工作(它无需评估导入即可工作)
这是我的类 RunSpring.java:
package run;
import org.springframework.beans.factory.BeanFactory;
import org.springframework.context.ApplicationContext;
import org.springframework.context.support.ClassPathXmlApplicationContext;
import helloworld.HelloSpringWorld;
public class RunSpring
{
public static void main(String[] args)
{
//App Context
ApplicationContext appContext = new ClassPathXmlApplicationContext("bean-data.xml");
BeanFactory beanFactory = appContext;
HelloSpringWorld instance = (HelloSpringWorld);
beanFactory.getBean("helloSpringWorld");
//Expression to be evaluated
instance.greeting("${5+5}");
}
}
这是我的类(class)HelloSpringWorld:
package helloworld;
import org.springframework.stereotype.Service;
//Expression imports
import org.springframework.expression.ExpressionParser;
import org.springframework.expression.Expression;
import org.springframework.expression.spel.standard.SpelExpressionParser;
@Service
public class HelloSpringWorld
{
public void greeting(String name)
{
//Expression Setup
ExpressionParser parser = new SpelExpressionParser();
Expression exp = parser.parseExpression(name);
String message = (String) exp.getValue();
System.out.println("Hello and welcome to Spring: " + message);
}
}
错误:解析有效表达式后,表达式中仍有更多数据:'lcurly({)'
有什么提示吗?
感谢您的宝贵时间。
最佳答案
如下调整greeting
方法。请注意,Integer.class
被传递给 getValue()
。
public void greeting(String name)
{
ExpressionParser parser = new SpelExpressionParser();
Expression exp = parser.parseExpression(name);
String message = exp.getValue(Integer.class).toString();
System.out.println("Hello and welcome to Spring: " + message);
}
然后调用:
instance.greeting("5+5");
关于java - Spring SpEL 错误,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/20225502/