/*
* Licensed to the Apache Software Foundation (ASF) under one or more contributor license
* agreements. See the NOTICE file distributed with this work for additional information regarding
* copyright ownership. The ASF licenses this file to You under the Apache License, Version 2.0 (the
* "License"); you may not use this file except in compliance with the License. You may obtain a
* copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software distributed under the License
* is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express
* or implied. See the License for the specific language governing permissions and limitations under
* the License.
*/
package org.apache.geode.internal.admin.statalerts;
import org.apache.geode.SystemFailure;
import java.util.Arrays;
import java.util.Collection;
import java.util.Collections;
/**
* This class acts as a helper for the AlertManager & AlertAggregator for the execution of the user
* specified functions
*
* This class also keeps a registry of all the functions which are supported, which should be used
* during creation of alert definition.
*
*/
public class FunctionHelper {
private static final short FUN_AVG = 1;
private static final short FUN_MIN = 2;
private static final short FUN_MAX = 3;
private static final short FUN_SUM = 4;
private static final String STR_AVG = "Average";
private static final String STR_MIN = "Min Value";
private static final String STR_MAX = "Max Value";
private static final String STR_ADD = "Sum";
/**
* This function returns the available function names.
*
* @return List of the function names.
*/
public static String[] getFunctionNames() {
return new String[] {STR_ADD, STR_AVG, STR_MIN, STR_MAX};
}
/**
* This method returns the function's name for the requested function identifier.
*
* @param functionId Identifier of the function
* @return Function name.
*/
public static String getFunctionName(short functionId) {
switch (functionId) {
case FUN_AVG:
return STR_AVG;
case FUN_MIN:
return STR_MIN;
case FUN_MAX:
return STR_MAX;
case FUN_SUM:
return STR_ADD;
default:
return null;
}
}
/**
* This function returns the function identifier for the requested function name.
*
* @param qFunctionName Name of the function
* @return Function identifier.
*/
public static short getFunctionIdentifier(String qFunctionName) {
if (qFunctionName == null)
return -1;
if (qFunctionName.equalsIgnoreCase(STR_ADD))
return FUN_SUM;
if (qFunctionName.equalsIgnoreCase(STR_AVG))
return FUN_AVG;
if (qFunctionName.equalsIgnoreCase(STR_MIN))
return FUN_MIN;
if (qFunctionName.equalsIgnoreCase(STR_MAX))
return FUN_MAX;
return -1;
}
/**
* Apply the given function of the given list of numbers and returns result
*
* @param functorId Id of function to be applied
* @param vals List of number on which function will be applied
*
*/
public static Number[] applyFunction(short functorId, Number[] vals) {
Number[] res = new Number[1];
switch (functorId) {
case FUN_SUM:
res[0] = SUM(vals);
return res;
case FUN_AVG:
res[0] = AVG(vals);
return res;
case FUN_MIN:
res[0] = MIN(vals);
return res;
case FUN_MAX:
res[0] = MAX(vals);
return res;
default:
return null;
}
}
/**
* Apply the SUM function on given list of number
*
* @param vals Array of number
*/
public static final Number SUM(Number[] vals) {
try {
double sum = 0.0;
for (int i = 0; i < vals.length; i++) {
sum = sum + vals[i].doubleValue();
}
return Double.valueOf(sum);
} catch (VirtualMachineError err) {
SystemFailure.initiateFailure(err);
// If this ever returns, rethrow the error. We're poisoned
// now, so don't let this thread continue.
throw err;
} catch (Throwable t) {
// Whenever you catch Error or Throwable, you must also
// catch VirtualMachineError (see above). However, there is
// _still_ a possibility that you are dealing with a cascading
// error condition, so you also need to check to see if the JVM
// is still usable:
SystemFailure.checkFailure();
return null;
}
}
/**
* Apply the Average function on given list of number
*
* @param vals Array of number
*/
public static final Number AVG(Number[] vals) {
try {
return Double.valueOf(SUM(vals).doubleValue() / vals.length);
} catch (VirtualMachineError err) {
SystemFailure.initiateFailure(err);
// If this ever returns, rethrow the error. We're poisoned
// now, so don't let this thread continue.
throw err;
} catch (Throwable ex) {
// Whenever you catch Error or Throwable, you must also
// catch VirtualMachineError (see above). However, there is
// _still_ a possibility that you are dealing with a cascading
// error condition, so you also need to check to see if the JVM
// is still usable:
SystemFailure.checkFailure();
return null;
}
}
/**
* Apply the Minimum function on given list of number
*
* @param vals Array of number
*/
public static final Number MIN(Number[] vals) {
try {
Collection col = Arrays.asList(vals);
Number min = (Number) Collections.max(col);
return min;
} catch (VirtualMachineError err) {
SystemFailure.initiateFailure(err);
// If this ever returns, rethrow the error. We're poisoned
// now, so don't let this thread continue.
throw err;
} catch (Throwable t) {
// Whenever you catch Error or Throwable, you must also
// catch VirtualMachineError (see above). However, there is
// _still_ a possibility that you are dealing with a cascading
// error condition, so you also need to check to see if the JVM
// is still usable:
SystemFailure.checkFailure();
return null;
}
}
/**
* Apply the Maximum function on given list of number
*
* @param vals Array of number
*/
public static final Number MAX(Number[] vals) {
try {
Collection col = Arrays.asList(vals);
Number max = (Number) Collections.max(col);
return max;
} catch (VirtualMachineError err) {
SystemFailure.initiateFailure(err);
// If this ever returns, rethrow the error. We're poisoned
// now, so don't let this thread continue.
throw err;
} catch (Throwable t) {
// Whenever you catch Error or Throwable, you must also
// catch VirtualMachineError (see above). However, there is
// _still_ a possibility that you are dealing with a cascading
// error condition, so you also need to check to see if the JVM
// is still usable:
SystemFailure.checkFailure();
return null;
}
}
}