Java Method from Class findMethod(Class c, String name, Class params[])

Description

find Method

License

Open Source License

Declaration

public static Method findMethod(Class<?> c, String name, Class<?> params[]) 

Method Source Code

//package com.java2s;
/*//w  ww.  j  a  v  a  2 s. c om
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import java.lang.reflect.Method;

import java.util.Hashtable;

public class Main {
    static Hashtable<Class<?>, Method[]> objectMethods = new Hashtable<Class<?>, Method[]>();

    public static Method findMethod(Class<?> c, String name, Class<?> params[]) {
        Method methods[] = findMethods(c);
        if (methods == null)
            return null;
        for (int i = 0; i < methods.length; i++) {
            if (methods[i].getName().equals(name)) {
                Class<?> methodParams[] = methods[i].getParameterTypes();
                if (methodParams == null)
                    if (params == null || params.length == 0)
                        return methods[i];
                if (params == null)
                    if (methodParams == null || methodParams.length == 0)
                        return methods[i];
                if (params.length != methodParams.length)
                    continue;
                boolean found = true;
                for (int j = 0; j < params.length; j++) {
                    if (params[j] != methodParams[j]) {
                        found = false;
                        break;
                    }
                }
                if (found)
                    return methods[i];
            }
        }
        return null;
    }

    @SuppressWarnings("unchecked")
    public static Method[] findMethods(Class<?> c) {
        Method methods[] = (Method[]) objectMethods.get(c);
        if (methods != null)
            return methods;

        methods = c.getMethods();
        objectMethods.put(c, methods);
        return methods;
    }
}

Related

1. existsMethod(final String clazz, final String name, final Class[] parameterTypes)
2. findMethod(Class javaClass, String methodName, Class[] methodParameterTypes)
3. findMethod(Method m, Class c)
4. findMethods(Class c)
5. getAllMethodsWithAnnotation( String packageName, Class annotation)
6. getDeclaredMethod(final Class clazz, final String methodName, final Class[] methodParameterTypes)