Java tutorial
/* * Copyright (c) 2015, WSO2 Inc. (http://www.wso2.org) All Rights Reserved. * * WSO2 Inc. 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.wso2.siddhi.extension.time; import org.apache.commons.lang3.time.FastDateFormat; import org.wso2.siddhi.core.config.ExecutionPlanContext; import org.wso2.siddhi.core.exception.ExecutionPlanRuntimeException; import org.wso2.siddhi.core.exception.OperationNotSupportedException; import org.wso2.siddhi.core.executor.ConstantExpressionExecutor; import org.wso2.siddhi.core.executor.ExpressionExecutor; import org.wso2.siddhi.core.executor.function.FunctionExecutor; import org.wso2.siddhi.extension.time.util.TimeExtensionConstants; import org.wso2.siddhi.query.api.definition.Attribute; import org.wso2.siddhi.query.api.exception.ExecutionPlanValidationException; import java.text.ParseException; import java.util.Calendar; import java.util.Date; /** * dateAdd(dateValue,expr,unit,dateFormat)/dateAdd(dateValue,expr,unit)/dateAdd(timestampInMilliseconds,expr,unit) * Returns added specified time interval to a date. * dateValue - value of date. eg: "2014-11-11 13:23:44.657", "2014-11-11" , "13:23:44.657" * unit - Which part of the date format you want to manipulate. eg: "MINUTE" , "HOUR" , "MONTH" , "YEAR" , "QUARTER" , * "WEEK" , "DAY" , "SECOND" * expr - In which amount, selected date format part should be incremented. eg: 2 ,5 ,10 etc * dateFormat - Date format of the provided date value. eg: yyyy-MM-dd HH:mm:ss.SSS * timestampInMilliseconds - date value in milliseconds.(from the epoch) eg: 1415712224000L * Accept Type(s) for dateAdd(dateValue,expr,unit,dateFormat): * dateValue : STRING * expr : INT * unit : STRING * dateFormat : STRING * Accept Type(s) for dateAdd(timestampInMilliseconds,expr,unit): * expr : INT * unit : STRING * timestampInMilliseconds : LONG * Return Type(s): STRING */ public class DateAddFunctionExtension extends FunctionExecutor { private Attribute.Type returnType = Attribute.Type.STRING; private boolean useDefaultDateFormat = false; private String dateFormat = null; private Calendar calInstance = Calendar.getInstance(); private String unit = null; @Override protected void init(ExpressionExecutor[] attributeExpressionExecutors, ExecutionPlanContext executionPlanContext) { if (attributeExpressionExecutors[0].getReturnType() != Attribute.Type.LONG && attributeExpressionExecutors.length == 3) { useDefaultDateFormat = true; dateFormat = TimeExtensionConstants.EXTENSION_TIME_DEFAULT_DATE_FORMAT; } if (attributeExpressionExecutors.length == 4) { if (attributeExpressionExecutors[0].getReturnType() != Attribute.Type.STRING) { throw new ExecutionPlanValidationException("Invalid parameter type found for the first argument of " + "time:dateAdd(dateValue,expr,unit,dateFormat) function, " + "required " + Attribute.Type.STRING + " but found " + attributeExpressionExecutors[0].getReturnType().toString()); } if (attributeExpressionExecutors[1].getReturnType() != Attribute.Type.INT) { throw new ExecutionPlanValidationException( "Invalid parameter type found for the second argument of " + "time:dateAdd(dateValue,expr,unit,dateFormat) function, " + "required " + Attribute.Type.INT + " but found " + attributeExpressionExecutors[1].getReturnType().toString()); } if (attributeExpressionExecutors[2].getReturnType() != Attribute.Type.STRING) { throw new ExecutionPlanValidationException("Invalid parameter type found for the third argument of " + "time:dateAdd(dateValue,expr,unit,dateFormat) function, " + "required " + Attribute.Type.STRING + " but found " + attributeExpressionExecutors[2].getReturnType().toString()); } if (attributeExpressionExecutors[3].getReturnType() != Attribute.Type.STRING) { throw new ExecutionPlanValidationException( "Invalid parameter type found for the fourth argument of " + "time:dateAdd(dateValue,expr,unit,dateFormat) function, " + "required " + Attribute.Type.STRING + " but found " + attributeExpressionExecutors[3].getReturnType().toString()); } } else if (attributeExpressionExecutors.length == 3) { if (useDefaultDateFormat) { if (attributeExpressionExecutors[0].getReturnType() != Attribute.Type.STRING) { throw new ExecutionPlanValidationException( "Invalid parameter type found for the first argument of " + "time:dateAdd(dateValue,expr,unit) function, " + "required " + Attribute.Type.STRING + " but found " + attributeExpressionExecutors[0].getReturnType().toString()); } if (attributeExpressionExecutors[1].getReturnType() != Attribute.Type.INT) { throw new ExecutionPlanValidationException( "Invalid parameter type found for the second argument of " + "time:dateAdd(dateValue,expr,unit) function, " + "required " + Attribute.Type.INT + " but found " + attributeExpressionExecutors[1].getReturnType().toString()); } if (attributeExpressionExecutors[2].getReturnType() != Attribute.Type.STRING) { throw new ExecutionPlanValidationException( "Invalid parameter type found for the second argument of " + "time:dateAdd(dateValue,expr,unit) function, " + "required " + Attribute.Type.STRING + " but found " + attributeExpressionExecutors[2].getReturnType().toString()); } } else { if (attributeExpressionExecutors[0].getReturnType() != Attribute.Type.LONG) { throw new ExecutionPlanValidationException( "Invalid parameter type found for the first argument of " + "time:dateAdd(timestampInMilliseconds,expr,unit) function, " + "required " + Attribute.Type.LONG + " but found " + attributeExpressionExecutors[0].getReturnType().toString()); } if (attributeExpressionExecutors[1].getReturnType() != Attribute.Type.INT) { throw new ExecutionPlanValidationException( "Invalid parameter type found for the second argument of " + "time:dateAdd(timestampInMilliseconds,expr,unit) function, " + "required " + Attribute.Type.INT + " but found " + attributeExpressionExecutors[1].getReturnType().toString()); } if (attributeExpressionExecutors[2].getReturnType() != Attribute.Type.STRING) { throw new ExecutionPlanValidationException( "Invalid parameter type found for the second argument of " + "time:dateAdd(timestampInMilliseconds,expr,unit) function, " + "required " + Attribute.Type.STRING + " but found " + attributeExpressionExecutors[2].getReturnType().toString()); } } } else { throw new ExecutionPlanValidationException("Invalid no of arguments passed to time:dateAdd() function, " + "required 3 or 4, but found " + attributeExpressionExecutors.length); } if (attributeExpressionExecutors[2] instanceof ConstantExpressionExecutor) { unit = ((String) ((ConstantExpressionExecutor) attributeExpressionExecutors[2]).getValue()) .toUpperCase(); } else { throw new OperationNotSupportedException("unit value has to be a constant"); } } @Override protected Object execute(Object[] data) { int expression; String date = null; FastDateFormat formattedDate; if (data.length == 4 || useDefaultDateFormat) { try { if (data[0] == null) { throw new ExecutionPlanRuntimeException("Invalid input given to time:dateAdd(date,expr," + "unit,dateFormat) function" + ". First " + "argument cannot be null"); } if (data[1] == null) { throw new ExecutionPlanRuntimeException("Invalid input given to time:dateAdd(date,expr," + "unit,dateFormat) function" + ". Second " + "argument cannot be null"); } if (!useDefaultDateFormat) { if (data[3] == null) { throw new ExecutionPlanRuntimeException("Invalid input given to time:dateAdd(date,expr," + "unit,dateFormat) function" + ". Fourth " + "argument cannot be null"); } dateFormat = (String) data[3]; } date = (String) data[0]; expression = (Integer) data[1]; formattedDate = FastDateFormat.getInstance(dateFormat); Date userSpecifiedDate = formattedDate.parse(date); calInstance.setTime(userSpecifiedDate); getProcessedCalenderInstance(unit, calInstance, expression); return formattedDate.format(calInstance.getTime()); } catch (ParseException e) { String errorMsg = "Provided format " + dateFormat + " does not match with the timestamp " + date + e.getMessage(); throw new ExecutionPlanRuntimeException(errorMsg, e); } catch (ClassCastException e) { String errorMsg = "Provided Data type cannot be cast to desired format. " + e.getMessage(); throw new ExecutionPlanRuntimeException(errorMsg, e); } } else if (data.length == 3) { if (data[0] == null) { throw new ExecutionPlanRuntimeException( "Invalid input given to time:dateAdd(timestampInMilliseconds," + "expr,unit) function" + ". First " + "argument cannot be null"); } if (data[1] == null) { throw new ExecutionPlanRuntimeException( "Invalid input given to time:dateAdd(timestampInMilliseconds," + "expr,unit) function" + ". Second " + "argument cannot be null"); } if (data[2] == null) { throw new ExecutionPlanRuntimeException( "Invalid input given to time:dateAdd(timestampInMilliseconds," + "expr,unit) function" + ". Third " + "argument cannot be null"); } try { long dateInMills = (Long) data[0]; calInstance.setTimeInMillis(dateInMills); unit = (String) data[2]; expression = (Integer) data[1]; getProcessedCalenderInstance(unit, calInstance, expression); return String.valueOf((calInstance.getTimeInMillis())); } catch (ClassCastException e) { String errorMsg = "Provided Data type cannot be cast to desired format. " + e.getMessage(); throw new ExecutionPlanRuntimeException(errorMsg, e); } } else { throw new ExecutionPlanRuntimeException("Invalid set of arguments given to time:dateAdd() function." + "Arguments should be either 3 or 4. "); } } public Calendar getProcessedCalenderInstance(String unit, Calendar calInstance, int expression) { if (unit.equals(TimeExtensionConstants.EXTENSION_TIME_UNIT_YEAR)) { calInstance.add(Calendar.YEAR, expression); } else if (unit.equals(TimeExtensionConstants.EXTENSION_TIME_UNIT_MONTH)) { calInstance.add(Calendar.MONTH, expression); } else if (unit.equals(TimeExtensionConstants.EXTENSION_TIME_UNIT_SECOND)) { calInstance.add(Calendar.SECOND, expression); } else if (unit.equals(TimeExtensionConstants.EXTENSION_TIME_UNIT_MINUTE)) { calInstance.add(Calendar.MINUTE, expression); } else if (unit.equals(TimeExtensionConstants.EXTENSION_TIME_UNIT_HOUR)) { calInstance.add(Calendar.HOUR, expression); } else if (unit.equals(TimeExtensionConstants.EXTENSION_TIME_UNIT_DAY)) { calInstance.add(Calendar.DAY_OF_MONTH, expression); } else if (unit.equals(TimeExtensionConstants.EXTENSION_TIME_UNIT_WEEK)) { calInstance.add(Calendar.WEEK_OF_YEAR, expression); } else if (unit.equals(TimeExtensionConstants.EXTENSION_TIME_UNIT_QUARTER)) { calInstance.add(Calendar.MONTH, expression * 3); } return calInstance; } @Override protected Object execute(Object data) { return null;//Since the EpochToDateFormat function takes in 2 parameters, this method does not get called. Hence, not implemented. } @Override public void start() { } @Override public void stop() { } @Override public Attribute.Type getReturnType() { return returnType; } @Override public Object[] currentState() { return new Object[0]; //No need to maintain a state. } @Override public void restoreState(Object[] state) { //Since there's no need to maintain a state, nothing needs to be done here. } }