code: private void completeCheck() throws SlickException {
  		int framebuffer = EXTFramebufferObject.glCheckFramebufferStatusEXT(EXTFramebufferObject.GL_FRAMEBUFFER_EXT); 
  		switch ( framebuffer ) {
  			case EXTFramebufferObject.GL_FRAMEBUFFER_COMPLETE_EXT:
  				break;
  			case EXTFramebufferObject.GL_FRAMEBUFFER_INCOMPLETE_ATTACHMENT_EXT:
  				throw new SlickException( "FrameBuffer: " + FBO
  						+ ", has caused a GL_FRAMEBUFFER_INCOMPLETE_ATTACHMENT_EXT exception" );
  			case EXTFramebufferObject.GL_FRAMEBUFFER_INCOMPLETE_MISSING_ATTACHMENT_EXT:
  				throw new SlickException( "FrameBuffer: " + FBO
  						+ ", has caused a GL_FRAMEBUFFER_INCOMPLETE_MISSING_ATTACHMENT_EXT exception" );
  			case EXTFramebufferObject.GL_FRAMEBUFFER_INCOMPLETE_DIMENSIONS_EXT:
  				throw new SlickException( "FrameBuffer: " + FBO
  						+ ", has caused a GL_FRAMEBUFFER_INCOMPLETE_DIMENSIONS_EXT exception" );
  			case EXTFramebufferObject.GL_FRAMEBUFFER_INCOMPLETE_DRAW_BUFFER_EXT:
  				throw new SlickException( "FrameBuffer: " + FBO
  						+ ", has caused a GL_FRAMEBUFFER_INCOMPLETE_DRAW_BUFFER_EXT exception" );
  			case EXTFramebufferObject.GL_FRAMEBUFFER_INCOMPLETE_FORMATS_EXT:
  				throw new SlickException( "FrameBuffer: " + FBO
  						+ ", has caused a GL_FRAMEBUFFER_INCOMPLETE_FORMATS_EXT exception" );
  			case EXTFramebufferObject.GL_FRAMEBUFFER_INCOMPLETE_READ_BUFFER_EXT:
  				throw new SlickException( "FrameBuffer: " + FBO
  						+ ", has caused a GL_FRAMEBUFFER_INCOMPLETE_READ_BUFFER_EXT exception" );
  			default:
  				throw new SlickException( "Unexpected reply from glCheckFramebufferStatusEXT: " + framebuffer);
  		}
  	}
docs: Check the FBO for completeness as shown in the LWJGL tutorial
  
  @throws SlickException Indicates an incomplete FBO