How to use

Constraint

in

org.apache.hadoop.hbase.constraint

 @Override
 public int compare(Constraint c1, Constraint c2) {
  // compare the priorities of the constraints stored in their configuration
  return Long.compare(c1.getConf().getLong(PRIORITY_KEY, DEFAULT_PRIORITY),
    c2.getConf().getLong(PRIORITY_KEY, DEFAULT_PRIORITY));
 }
};

@Override
public void prePut(ObserverContext<RegionCoprocessorEnvironment> e, Put put,
  WALEdit edit, Durability durability) throws IOException {
 // check the put against the stored constraints
 for (Constraint c : constraints) {
  c.check(put);
 }
 // if we made it here, then the Put is valid
}

   .asSubclass(Constraint.class);
 Constraint constraint = clazz.getDeclaredConstructor().newInstance();
 constraint.setConf(conf);
 constraints.add(constraint);
} catch (InvocationTargetException | NoSuchMethodException | ClassNotFoundException |

@Test
public void testConfigurationPreserved() throws Throwable {
 Configuration conf = new Configuration();
 conf.setBoolean("_ENABLED", false);
 conf.setLong("_PRIORITY", 10);
 HTableDescriptor desc = new HTableDescriptor(TableName.valueOf(name.getMethodName()));
 Constraints.add(desc, AlsoWorks.class, conf);
 Constraints.add(desc, WorksConstraint.class);
 assertFalse(Constraints.enabled(desc, AlsoWorks.class));
 List<? extends Constraint> constraints = Constraints.getConstraints(desc,
   this.getClass().getClassLoader());
 for (Constraint c : constraints) {
  Configuration storedConf = c.getConf();
  if (c instanceof AlsoWorks)
   assertEquals(10, storedConf.getLong("_PRIORITY", -1));
  // its just a worksconstraint
  else
   assertEquals(2, storedConf.getLong("_PRIORITY", -1));
 }
}

 @Override
 public void prePut(ObserverContext<RegionCoprocessorEnvironment> e, Put put,
   WALEdit edit, boolean writeToWAL) throws IOException {
  // check the put against the stored constraints
  for (Constraint c : constraints) {
   c.check(put);
  }
  // if we made it here, then the Put is valid
 }
}

   .asSubclass(Constraint.class);
 Constraint constraint = clazz.newInstance();
 constraint.setConf(conf);
 constraints.add(constraint);
} catch (ClassNotFoundException e1) {

 @Override
 public int compare(Constraint c1, Constraint c2) {
  // compare the priorities of the constraints stored in their configuration
  return Long.valueOf(c1.getConf().getLong(PRIORITY_KEY, DEFAULT_PRIORITY))
    .compareTo(c2.getConf().getLong(PRIORITY_KEY, DEFAULT_PRIORITY));
 }
};

 @Override
 public void prePut(ObserverContext<RegionCoprocessorEnvironment> e, Put put,
   WALEdit edit, Durability durability) throws IOException {
  // check the put against the stored constraints
  for (Constraint c : constraints) {
   c.check(put);
  }
  // if we made it here, then the Put is valid
 }
}

   .asSubclass(Constraint.class);
 Constraint constraint = clazz.newInstance();
 constraint.setConf(conf);
 constraints.add(constraint);
} catch (ClassNotFoundException e1) {

 @Override
 public int compare(Constraint c1, Constraint c2) {
  // compare the priorities of the constraints stored in their configuration
  return Long.valueOf(c1.getConf().getLong(PRIORITY_KEY, DEFAULT_PRIORITY))
    .compareTo(c2.getConf().getLong(PRIORITY_KEY, DEFAULT_PRIORITY));
 }
};

@Test
public void testConfigurationPreserved() throws Throwable {
 Configuration conf = new Configuration();
 conf.setBoolean("_ENABLED", false);
 conf.setLong("_PRIORITY", 10);
 HTableDescriptor desc = new HTableDescriptor(TableName.valueOf(name.getMethodName()));
 Constraints.add(desc, AlsoWorks.class, conf);
 Constraints.add(desc, WorksConstraint.class);
 assertFalse(Constraints.enabled(desc, AlsoWorks.class));
 List<? extends Constraint> constraints = Constraints.getConstraints(desc,
   this.getClass().getClassLoader());
 for (Constraint c : constraints) {
  Configuration storedConf = c.getConf();
  if (c instanceof AlsoWorks)
   assertEquals(10, storedConf.getLong("_PRIORITY", -1));
  // its just a worksconstraint
  else
   assertEquals(2, storedConf.getLong("_PRIORITY", -1));
 }
}