/*
* Copyright 2004-2005 the original author or authors.
*
* 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 org.springmodules.validation.bean.rule;
import org.springmodules.validation.bean.rule.resolver.ErrorArgumentsResolver;
import org.springmodules.validation.util.condition.Condition;
import org.springmodules.validation.util.condition.common.AlwaysTrueCondition;
import org.springmodules.validation.bean.context.ValidationContextHolder;
import org.springmodules.validation.bean.context.ValidationContext;
import org.springmodules.validation.bean.context.ValidationContextUtils;
/**
* A super class for all specific validation rules.
*
* @author Uri Boness
*/
public abstract class AbstractValidationRule implements ValidationRule {
private String errorCode;
private String defaultErrorMessage;
private ErrorArgumentsResolver errorArgumentsResolver;
private Condition applicabilityCondition;
private String[] contextTokens;
/**
* Constructs a new AbstractValidationRule with a default error code. By default, the error arguments
* of this validation rule will only return the validated object itself.
*
* @param defaultErrorCode
*/
protected AbstractValidationRule(String defaultErrorCode) {
this(defaultErrorCode, createErrorArgumentsResolver(new Object[0]));
}
/**
* Constructs a new AbstractValidationRule with a default error code and error argument resolver.
*
* @param defaultErrorCode The default error code for this validation rule.
* @param defaultErrorArgumentsResolver The argument resolver for this validation rule.
*/
protected AbstractValidationRule(String defaultErrorCode, ErrorArgumentsResolver defaultErrorArgumentsResolver) {
this.errorCode = defaultErrorCode;
this.defaultErrorMessage = this.errorCode;
this.errorArgumentsResolver = defaultErrorArgumentsResolver;
this.applicabilityCondition = new AlwaysTrueCondition();
this.contextTokens = null;
}
/**
* Checks if this validation rule is applicable on a given object by performing the following two steps:
* <ol>
* <li>If the object is <code>null</code> and {@link #supportsNullValues()} returns <code>false</code>
* then returning <code>false</code>.</li>
* <li>Returning whatever the applicablity condition check returns for the given object
* ({@link #setApplicabilityCondition(org.springmodules.validation.util.condition.Condition)})</li>
*
* @see ValidationRule#isApplicable(Object)
*/
public boolean isApplicable(Object obj) {
if (contextTokens != null && !checkContexts(contextTokens)) {
return false;
}
if (obj == null && !supportsNullValues()) {
return false;
}
return applicabilityCondition.check(obj);
}
/**
* @see org.springmodules.validation.bean.rule.ValidationRule#getErrorCode()
*/
public String getErrorCode() {
return errorCode;
}
/**
* Returns the error arguments for this validation rule based on the given validated object. The arguments are
* determined by the associated {@link ErrorArgumentsResolver}.
*
* @see #setErrorArgumentsResolver(org.springmodules.validation.bean.rule.resolver.ErrorArgumentsResolver)
* @see ValidationRule#getErrorArguments(Object)
*/
public Object[] getErrorArguments(Object obj) {
return errorArgumentsResolver.resolveArguments(obj);
}
/**
* @see org.springmodules.validation.bean.rule.ValidationRule#getDefaultErrorMessage()
*/
public String getDefaultErrorMessage() {
return defaultErrorMessage;
}
/**
* Determines whether this validation rule supports <code>null</code> values. This method by default returns false,
* any sub-class that supports <code>null</code> values should override this method and return <code>true</code>.
*
* @return whether this validation rule supports <code>null</code> values.
*/
protected boolean supportsNullValues() {
return false;
}
//================================================== Setters =======================================================
/**
* Sets the error code of this validation rule.
*
* @param errorCode The error code of this validation rule.
*/
public void setErrorCode(String errorCode) {
this.errorCode = errorCode;
}
/**
* Sets the default error message of this validation rule.
*
* @param defaultErrorMessage The default error message of this validation rule.
*/
public void setDefaultErrorMessage(String defaultErrorMessage) {
this.defaultErrorMessage = defaultErrorMessage;
}
/**
* Sets the {@link ErrorArgumentsResolver} that will be used by this validation to extract the error arguments
* based on the validated object.
*
* @param errorArgumentsResolver The error argument resolver that will be used by this validator.
*/
public void setErrorArgumentsResolver(ErrorArgumentsResolver errorArgumentsResolver) {
this.errorArgumentsResolver = errorArgumentsResolver;
}
/**
* Sets the applicability condition that along with the {@link #supportsNullValues()} method determines whether
* this condition is applicable on a given object or not.
*
* @param applicabilityCondition The applicability condition that will be used by this validation rule when deciding
* whether it is applicable on a given object.
*/
public void setApplicabilityCondition(Condition applicabilityCondition) {
this.applicabilityCondition = applicabilityCondition;
}
/**
* Sets the validation contexts names in which this validation rule is applicable.
*
* @param contextTokens The validation context names in which this validation rule is applicable. <code>null</code>
* represents applicability in any context (even if one doesn't exsit).
*/
public void setContextTokens(String[] contextTokens) {
this.contextTokens = contextTokens;
}
//=============================================== Helper Methods ===================================================
/**
* A helper method for sub-classes helping with the creation of error argument resolvers. The resolver created by
* this method will return an array that contains the validated object and the given <code>arg</code> as the error
* arguments.
*
* @param arg The error argument to be returned along with the validated object.
* @return The created error arguments resolver.
*/
protected static ErrorArgumentsResolver createErrorArgumentsResolver(Object arg) {
return createErrorArgumentsResolver(new Object[]{arg});
}
/**
* A helper method for sub-classes helping with the creation of error argument resolvers. The resolver created by
* this method will return an array that contains the validated object and the given arguments as the error
* arguments.
*
* @param arg1 The error argument to be returned in position {1}
* @param arg2 The error argument to be returned in position {2}
* @return The created error arguments resolver.
*/
protected static ErrorArgumentsResolver createErrorArgumentsResolver(Object arg1, Object arg2) {
return createErrorArgumentsResolver(new Object[]{arg1, arg2});
}
/**
* A helper method for sub-classes helping with the creation of error argument resolvers. The resolver created by
* this method will return an array that contains the validated object and the given arguments as the error
* arguments.
*
* @param arg1 The error argument to be returned in position {1}
* @param arg2 The error argument to be returned in position {2}
* @param arg3 The error argument to be returned in position {3}
* @return The created error arguments resolver.
*/
protected static ErrorArgumentsResolver createErrorArgumentsResolver(Object arg1, Object arg2, Object arg3) {
return createErrorArgumentsResolver(new Object[]{arg1, arg2, arg3});
}
/**
* A helper method for sub-classes helping with the creation of error argument resolvers. The resolver created by
* this method will return an array that contains the validated object and the given arguments as the error
* arguments.
*
* @param arguments The error arguments that will be return along with the validated object, starting in position {1}.
* @return The created error arguments resolver.
*/
protected static ErrorArgumentsResolver createErrorArgumentsResolver(final Object[] arguments) {
return new ErrorArgumentsResolver() {
public Object[] resolveArguments(Object obj) {
Object[] result = new Object[arguments.length + 1];
System.arraycopy(arguments, 0, result, 1, arguments.length);
result[0] = obj;
return result;
}
};
}
protected static boolean checkContexts(String[] contextTokens) {
return ValidationContextUtils.tokensSupportedByCurrentContext(contextTokens);
}
}