Getting "Unable to find unambiguous method" when calling an enum function from JSF page in EAP 7.x

Solution Verified - Updated

Environment

Red Hat JBoss Enterprise Application Platform (EAP) 7.x

Issue

Seeing javax.el.ELException while trying to invoke a JSF page example.xhtml. The called function should use an enum as an input parameter but the EL-parser is expecting a string value

SEVERE [javax.enterprise.resource.webcontainer.jsf.application] (default task-1) Error Rendering View[/example.xhtml]: javax.el.ELException: /example.xhtml @17,90 value="#{foo.getPerson('MY_ENUM').nameS}": Unable to find unambiguous method: class com.example.entity.foo.getPerson(java.lang.String)

Also, the same code works on previous JBoss EAP 6.4.x version.

Resolution

Two Jira's were opened to have this issue fixed, for JBoss EAP 7.1.z and for JBoss EAP 7.2.z. The workaround is:

  • Remove the superclass, for example:
package com.entity;

import com.constants.MyEnum;

import java.util.HashMap;
import java.util.Map;

public class MyClass extends MySuperclass {

    public MyEntity getPerson(MyEnum enum) { ... }

}

to

package com.entity;

import com.constants.MyEnum;

import java.util.HashMap;
import java.util.Map;

public class MyClass {

    public MyEntity getPerson(MyEnum enum) { ... }

}
  • Change the parameter to String instead of Enum, for example:
package com.entity;

import com.constants.MyEnum;

import java.util.HashMap;
import java.util.Map;

public class MyClass extends MySuperclass {

    public MyEntity getPerson(MyEnum enum) { ... }

}

to

package com.entity;

import com.constants.MyEnum;

import java.util.HashMap;
import java.util.Map;

public class MyClass {

    public MyEntity getPerson(String enum) { ... }

}

Root Cause

The Expression Language 3 (EL-API-3) present in EAP 7.x is not able to find the method with an enum as a parameter, however, Expression Language 2.2 (EL-API-2.2) present in EAP 6.4. x is able to identify the method with an enun even though the JSF page passes the parameter as a string value.

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