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This example shows how easy is in Java to use reflection for executing a method in a class. 

In the example both the class and the method names are specified via strings. 

The method used in the example includes also a String parameter to be passed in and it returns another String.

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== the article ==
This example is composed of two class files: 
:Reflection
;containing the main method and executing all the fun part
:DynamicallyPointedClass
;containing the method to be called, it's a very easy dummy class

Inside the main method of '''Reflection''' you can notice the steps required: 
#obtain the java.lang.Class object containing the uninstantiated class
#obtain from the java.lang.Class the java.lang.reflect.Method that we will want to execute
#execute the invoke() of the '''method''' with the parameters
#output the resulting object. 

note that: 
#we don't know a priori the type of '''class1''' so to make it ''generic proof'' we need to assign to it a type Class<?>
#we don't know a priori the type returned by '''method''' so it will be assigned to an object. Ready eventually to be casted to some more appropriate type.
#the reflection throws a bunch of different Exceptions, lot of things may go wrong in this process

== DynamicallyPointedClass ==
{{versioned code|url=https://svn2.hosted-projects.com/wikijava/articles/dongiulio/SVN_LOCAL/org/wikijava/reflection/Reflection.java}}
<source lang="java5">package com.wikijava.reflection.pointed;

/**
 * this is the dummy class containing a method it serves as example for the
 * reflection the class implements the method <b>method</b> that will be called
 * by the reflection procedures
 * 
 * @author Giulio
 */
public class DynamicallyPointedClass {
    private static final String HELLO = "Hello "; //$NON-NLS-1$

    /**
     * 
     * simply gets a String and returns another String
     * 
     * @param name
     * @return a String
     */
    public static String method(String name) {
	return HELLO + name;
    }
}</source>[[Language::java5| ]]
== Reflection ==
<source lang="java5">package com.wikijava.reflection;

import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Method;

/**
 * this example executes dynamically a method on a class, the class is
 * dynamically choosen via a string, and so is the method
 * 
 * 
 * @author Giulio
 */
public class Reflection {

    private static final String NAME = "Giulio"; //$NON-NLS-1$

    private static final String METHOD = "method"; //$NON-NLS-1$

    private static final String CLASS = "com.wikijava.reflection.pointed.DynamicallyPointedClass"; //$NON-NLS-1$

    /**
     * @param args
     */
    public static void main(String[] args) {

	Class<?> class1;
	try {
	    class1 = Class.forName(CLASS);
	    Method method = class1.getMethod(METHOD, String.class);
	    Object o = method.invoke(null, NAME);
	    System.out.println(o);
	} catch (ClassNotFoundException e) {
	    e.printStackTrace();
	} catch (IllegalArgumentException e) {
	    e.printStackTrace();
	} catch (IllegalAccessException e) {
	    e.printStackTrace();
	} catch (InvocationTargetException e) {
	    e.printStackTrace();
	} catch (SecurityException e) {
	    e.printStackTrace();
	} catch (NoSuchMethodException e) {
	    e.printStackTrace();
	}

    }

}</source>[[Language::java5| ]]

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