code: /** 
   * Tests access to subsystem attributes
   */
  @Test public void testSubsystemReadWriteOperations() throws Exception {
    KernelServices services=this.buildKernelServices();
    ModelNode result=services.executeOperation(getSubsystemReadOperation(JGroupsSubsystemResourceDefinition.Attribute.DEFAULT_CHANNEL));
    Assert.assertEquals(result.get(FAILURE_DESCRIPTION).asString(),SUCCESS,result.get(OUTCOME).asString());
    Assert.assertEquals("ee",result.get(RESULT).asString());
    result=services.executeOperation(getSubsystemWriteOperation(JGroupsSubsystemResourceDefinition.Attribute.DEFAULT_CHANNEL,"bridge"));
    Assert.assertEquals(result.get(FAILURE_DESCRIPTION).asString(),SUCCESS,result.get(OUTCOME).asString());
    result=services.executeOperation(getSubsystemReadOperation(JGroupsSubsystemResourceDefinition.Attribute.DEFAULT_CHANNEL));
    Assert.assertEquals(result.get(FAILURE_DESCRIPTION).asString(),SUCCESS,result.get(OUTCOME).asString());
    Assert.assertEquals("bridge",result.get(RESULT).asString());
  }
  