searching the code of com.jmex.effects.water.WaterRenderPass i found:
try {
testShader.load( WaterRenderPass.class.getClassLoader().getResource( currentShaderStr + ".vert" ),
WaterRenderPass.class.getClassLoader().getResource( currentShaderStr + ".frag" ) );
testShader.apply();
Util.checkGLError();
} catch( OpenGLException e ) {
e.printStackTrace();
return;
}
Util and OpenGLException are classes from lwjgl. I think there is missing some kind of abstraction there.
That checkError and the catch is only a debugging help to notice if there a problem with the shaders - it can safely be removed in production or if we ever get another gl library (e.g. jogl).