Java tutorial
/* * Copyright 2002-2006,2009 The Apache Software Foundation. * * Licensed 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 com.opensymphony.xwork2.validator.validators; import org.apache.logging.log4j.Logger; import org.apache.logging.log4j.LogManager; import com.opensymphony.xwork2.validator.ValidationException; import org.apache.commons.lang3.StringUtils; import java.util.Collection; /** * Base class for range based validators. Use this class to develop any other custom range validators. */ public abstract class RangeValidatorSupport<T extends Comparable> extends FieldValidatorSupport { private static final Logger LOG = LogManager.getLogger(RangeValidatorSupport.class); private final Class<T> type; private T min; private String minExpression; private T max; private String maxExpression; protected RangeValidatorSupport(Class<T> type) { this.type = type; } public void validate(Object object) throws ValidationException { Object obj = getFieldValue(getFieldName(), object); // if there is no value - don't do comparison // if a value is required, a required validator should be added to the field if (obj == null) { return; } T min = getMin(); T max = getMax(); if (obj.getClass().isArray()) { Object[] values = (Object[]) obj; for (Object objValue : values) { validateValue(object, (Comparable<T>) objValue, min, max); } } else if (Collection.class.isAssignableFrom(obj.getClass())) { Collection<?> values = (Collection<?>) obj; for (Object objValue : values) { validateValue(object, (Comparable<T>) objValue, min, max); } } else { validateValue(object, (Comparable<T>) obj, min, max); } } protected void validateValue(Object object, Comparable<T> value, T min, T max) { setCurrentValue(value); // only check for a minimum value if the min parameter is set if ((min != null) && (value.compareTo(min) < 0)) { addFieldError(getFieldName(), object); } // only check for a maximum value if the max parameter is set if ((max != null) && (value.compareTo(max) > 0)) { addFieldError(getFieldName(), object); } setCurrentValue(null); } public void setMin(T min) { this.min = min; } public T getMin() { return getT(min, minExpression, type); } public T getMax() { return getT(max, maxExpression, type); } public void setMinExpression(String minExpression) { LOG.debug("${minExpression} was defined as [{}]", minExpression); this.minExpression = minExpression; } public void setMax(T max) { this.max = max; } public void setMaxExpression(String maxExpression) { LOG.debug("${maxExpression} was defined as [{}]", maxExpression); this.maxExpression = maxExpression; } protected T getT(T minMax, String minMaxExpression, Class<T> toType) { if (minMax != null) { return minMax; } else if (StringUtils.isNotEmpty(minMaxExpression)) { return (T) parse(minMaxExpression, toType); } else { return null; } } }