How get special method of class in java?

Question

I have a class with some methods in Java as follows:

public class Class1
{
    private String a;
    private String b;


    public setA(String a_){
        this.a = a_;
    }

    public setb(String b_){
        this.b = b_;
    }

    public String getA(){
        return a;
    }

    @JsonIgnore
    public String getb(){
        return b;
    }
}

I want to get all methods in Class1 that start with the String get which are not declared with the @JsonIgnore annotation.

How do I do this?

You will get some idea from this : http://stackoverflow.com/questions/6593597/java-seek-a-method-with-specific-annotation-and-its-annotation-element — RahulArackal, Apr 23 '15 at 08:33
I'm guessing you are trying to convert the java class to json. Try this library http://flexjson.sourceforge.net/ . It handles multiple levels, custom transformations and include/exclude paths. — Goose, Apr 23 '15 at 08:39

Tim Biegeleisen · Accepted Answer · 2015-04-23T08:52:13.897

4

You can use Java Reflection to iterate over all public and private methods:

Class1 obj = new Class1();

Class c = obj.getClass();
for (Method method : c.getDeclaredMethods()) {
    if (method.getAnnotation(JsonIgnore.class) == null &&
        method.getName().substring(0,3).equals("get")) {
        System.out.println(method.getName());
    }
}

edited Apr 23 '15 at 08:52

answered Apr 23 '15 at 08:31

Tim Biegeleisen

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score 2 · Answer 2 · answered Apr 23 '15 at 08:30

You can use java reflections. Eg.

import static org.reflections.ReflectionUtils.*;

     Set<Method> getters = getAllMethods(someClass,
          withModifier(Modifier.PUBLIC), withPrefix("get"), withParametersCount(0));

     //or
     Set<Method> listMethods = getAllMethods(List.class,
          withParametersAssignableTo(Collection.class), withReturnType(boolean.class));

     Set<Fields> fields = getAllFields(SomeClass.class, withAnnotation(annotation), withTypeAssignableTo(type));

You should mention that you are using Google Reflections. – maba Apr 23 '15 at 08:39 — maba, Apr 23 '15 at 08:39

score 1 · Answer 3 · answered Apr 23 '15 at 08:38

With Reflection we can achieve this.

public static void main(String[] args) {
    Method[] methodArr = Class1.class.getMethods();

    for (Method method : methodArr) {
        if (method.getName().contains("get") && method.getAnnotation(JsonIgnore.class)==null) {
            System.out.println(method.getName());
        }
    }
}

How get special method of class in java?

3 Answers3