Finding low cost sources for showing your Java skills can be tricky, here is a 2 in 1 solution.

Odesk has a Java test , a J2ME test and a java Beans test amongst otheres.

Here is the content of the Java test

Syllabus of the Test Core Fundamentals
Classes
Polymorphism
Exception Handling
JDBC
Inheritance
AWT
Applets
IO
Swing
Threads

So take the test , show off your certified graphic and search for some freelance java jobs, note the Java jobs are split into various categories such as JSP, J2ME on the site

The On Demand Global Workforce - oDesk

Java 2: JSP and Servlets

Introduction

Introduction to the Course
What is a JavaServer Page?
What is a Java Servlet?

The Container

Static and Dynamic Web Pages
The Container
Installation
The Environment
Starting the Server

Basic Servlets

Writing and Compiling a Servlet
Creating an Application
Two Ways to Deploy
Yet Another Deploy
Servlet Mapping
An Interception Servlet

Basic JSPs

Writing a JSP
JSP to Java Translation
JSP Elements
Imports/Globals/Methods pt. 1
Imports/Globals/Methods pt. 2
Tracking an Error
The Custom Error Page

XML and Ant

Introduction to XML
The DTD
Parameters and Error Pages
Download and Install Ant
Tasks and Properties
Basic War Building
Compiling and Deploying
A Jar File pt. 1
A Jar File pt. 2
JSPs and HTML Files
Packages

HTML and HTML Forms

Tables
Images
Style Sheets
Coding a Form
Text Boxes and Text Areas
Check Boxes and Radio Buttons
Pull Down and Scrolled List

JSP Tags

A JSP Tag Handler
A Tag with a Body
A Tag with Attributes pt. 1
A Tag with Attributes pt. 2
Before and After the Body
Tag Libraries
A Few Handy JSTL Tags
Parameters and Looping
EJB
Looping forEach
Import and Choose
Running Timestamp

Cookies and Session Tracking

The Purpose of a Cookie
Setting and Getting Servlet Cookies
Setting and Getting JSP Cookies
URL Encoding in a JSP
Explicit URL Encoding
Session Timeout

Errors and Exceptions

Declaring Error Handling in web.xml
An Error Sending Servlet
Servlet Throwing an Exception
JSP Errors and Exceptions
Logging

Files

A Servlet to Setup a Download
A More General Download Servlet
Viewing a Resource File
Request Headers
An Applet in a JSP
An Applet with Parameters in a JSP
An Applet in a Servlet
JavaScript in a JSP
JavaScript in a Servlet
Thread Safe Code

Java 2: Graphics

Introduction

Course Introduction
Course Overview

Getting Started

Where to Get Java
The Command Line Installation
Writing and Compiling a Program
The Mainline

The Graphics Object and Colors

The Graphics Class
The Graphics2D Class
The Coordinate System
Filling a Window with Color
Inventing a Color of Your Own
Shading Up and Down
A Color Gradient
Color Gradient Directions
Cyclical Color Gradient

Positioning/Sizing/Rotating

Polygon
Translate and Rotate
Circling
Scaling
Shearing
The Affine Transform

Fundamental Drawing

A Random Drawing
Arcs
Rounded Rectangles
Basic Line Drawing
Corners and Ends
Dashed Lines

Fundamental Fonts

Font Measuring
Positioning Text
Font List

Image Files

Loading Image Files
Scaling
Types of Scaling
Pixel by Pixel pt. 1
Pixel by Pixel pt. 2
Convolving pt. 1
Convolving pt. 2
Transformation pt. 1
Transformation pt. 2
Compositing
Cross Fading

The Mouse and Keyboard

Reading Mouse Events
Mouse Motion
All Mouse Events
Reading Keyboard Events
Selecting a Mouse Cursor
Dragging Objects
Dragging Solid Objects
Rubberbanding

Making Shapes and Fitting Curves

Building a Rectangle with GeneralPath
Scaling and Zig Zagging
The Winding Rule
Quadratic Curves
Asymmetric Quadratic Curves
Cubic Curves
Asymmetric Cubic Curves
Attaching Shapes with GeneralPath
Combining Shapes with GeneralPath
Combining Shapes with an Area Object
Crop Image
Filling an Area

Fitting Text

Ways of Displaying Text pt. 1
Ways of Displaying Text pt. 2
Positioning Text
Text Attributes
Drawn Letters
Letters with Pictures
Dynamic Resizing of Text

Stupid Animation Tricks

Flicker
No Flicker
No Flicker Applet
Pong and Electrons pt. 1
Pong and Electrons pt. 2

Java 2: Certified Programmer

Introduction

Course Introduction
The Exam Pt.1
The Exam Pt.2

Object Oriented Programming

An Object
A Class
Inheritance
Instantiation
An Abstract Class
An Interface
Polymorphism

Declarations & Operations

Hello World
Names
Data Types
Data Types Pt.2
Data Declaration
Literal Values
Literal Values Pt.2
Arithmetic Operators
Bitwise Operators
Assignment Operators
Widening and Narrowing
Boolean Operations

References & Objects

Instantiation & References
Polymorphism
Garbage Collection
Arrays
Multidimensional Arrays
Array Initial Values

The Structure of Java

The Java Virtual Machine
Contents of a Class
Class Modifiers
Data Modifiers
Method Modifiers
Constructors
Methods Pt.1
Methods Pt.2
Methods Pt.3
Methods Pt.4

Flow Control

Boolean Expressions
If/Else
While & Do/While
For Pt.1
For Pt.2
Switch/Case
Break & Continue
Throwing an Exception Pt.1
Throwing an Exception Pt.2
The Try/Catch/Finally Block
Overloading & Overriding Methods
Some Specific Exceptions
Assert

Language Fundamentals

Packages
Import
Classpath & Jar Files
Abstract Class
Interfaces
Java Keywords
Nested Classes
An Anonymous Class
Enumerated Types
Comparing Objects
Java Bean Naming Standards

java.io & java.text

File Input & Output
Stream Input & Output
Serializable Classes
Format & Parse Dates
Number & Wrapper Classes
NumberFormat

Threads

java.lang.Thread
java.lang.Runnable
Synchronized
Wait & Notify
More About Threads

java.lang & java.util

java.lang.Math
Strings
Boxing & Unboxing
java.lang.System
The Set Collection
List, Queue, & Map
Generic Syntax
Selecting a Collection Class
Hashcode
java.util.regex
Pattern & Matcher
java.lang.Comparable
Sorting & Searching

J2EE (Java 2 Enterprise Edition)

Introduction to J2EE

Course Introduction
Tiered Architecture
Servlets & JSP
Enterprise JavaBeans
XML
Transactions
Installation
Setting the PATH
Starting & Stopping the Servers

JavaServer Pages

Introduction to JSP
Writing JSP Pages
Deploying a JSP Page
Implicit Objects
The Request & Response Objects
Cookies & Sessions
Init Parameters & Context
Implict Object Classes
JSP Tags
The Page Directive
Include & Forward

JavaServer Pages Code

Expression Language Basics
Method & Object References
JSP to Java Mapping
A Tag Handler Pt.1
A Tag Handler Pt.2
Two More Tag Handlers Pt.1
Two More Tag Handlers Pt.2
Tag Libraries

Servlets

Basic Servlet Design
A Simple Servlet
Posting to a Servlet
Catching Exceptions
Sending Messages
Using Multiple Servlets
Multi-Threading
Event Logging
Cookies
Filters
MVC

Database

JDBC & Drivers
The Console
Making a Connection Pt.1
Making a Connection Pt.2
Making a Simple Connection
Making a Table
Display a Table
Statements & Result Sets
Data Type Methods
Writing Through the ResultSet
Creating a Prepared Statement
Transactions
A Transaction Example
Batch Updates
Locking

Enterprise JavaBeans

Introduction to EJB
The Kinds of Beans
Writing a Stateless Session Bean
Deploying a Bean Pt.1
Deploying a Bean Pt.2
Calling Bean Methods
A Session Bean with a State
Writing a Stateful Session Bean
Entity Beans
Synchronization of Entity Beans
Message Beans
Code of a Message Bean

Web Services

Introduction to Web Services

JAX-RPC
Source Code of a Web Service
Web Service Description Language
Deploying a Web Service Pt.1
Deploying a Web Service Pt.2
Web Service Client