关于java:MVEL自定义函数重复掉用报错duplicate-function

MVEL 自定义表达式反复掉用报错：duplicate function

起因：第一次调用时会将 function 缓存，再次调用时提醒函数反复

计划：先将 funciton 放入缓存，再次调用时间接调用申明缓存中的函数

• 自定义函数名，不要与参数名雷同

示例代码：

@RunWith(SpringRunner.class)
@SpringBootTest
public class MvelTest {
        
    @Test
    public void evalTest(){
        // 表达式
        String roundup = "def roundup(num) {roundnum = null; if(num != null){int roundnum = Math.round(num); } return roundnum; }";
        VariableResolverFactory functionFactory = new MapVariableResolverFactory();
        MVEL.eval(roundup, functionFactory);

        VariableResolverFactory resolverFactory = new MapVariableResolverFactory();
        resolverFactory.setNextFactory(functionFactory);
        Map<String, Object> map = new HashMap<String, Object>();
        map.put("A", new BigDecimal(2.33));
        map.put("B", new BigDecimal(4));
        String exp = "roundup(A*B)";
        System.out.println(MVEL.eval(exp, map, resolverFactory));

        System.out.println("------------");

        VariableResolverFactory resolverFactory2 = new MapVariableResolverFactory();
        resolverFactory2.setNextFactory(functionFactory);
        Map<String, Object> map2 = new HashMap<String, Object>();
        map2.put("A", new BigDecimal(3.33));
        map2.put("B", new BigDecimal(2));
        System.out.println(MVEL.eval(exp, map2, resolverFactory2));
    }
}

错误代码示例

向缓存中退出 roundup 函数

第一次执行胜利

再次调用再次向缓存中退出 roundup 函数

VariableResolverFactory 中存在函数抛出异样