org.springmodules.validation.valang.javascript.ValangJavaScriptTranslator Maven / Gradle / Ivy
/*
* Copyright 2002-2005 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.valang.javascript;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.Reader;
import java.io.Writer;
import java.util.Calendar;
import java.util.Collection;
import java.util.Date;
import java.util.Iterator;
import org.apache.commons.collections.Predicate;
import org.apache.commons.collections.functors.AndPredicate;
import org.apache.commons.collections.functors.NotPredicate;
import org.apache.commons.collections.functors.OrPredicate;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.springframework.context.support.MessageSourceAccessor;
import org.springframework.core.ReflectiveVisitorHelper;
import org.springframework.util.Assert;
import org.springframework.util.ClassUtils;
import org.springframework.util.StringUtils;
import org.springframework.web.util.JavaScriptUtils;
import org.springmodules.validation.valang.functions.*;
import org.springmodules.validation.valang.predicates.BasicValidationRule;
import org.springmodules.validation.valang.predicates.GenericTestPredicate;
import org.springmodules.validation.valang.predicates.Operator;
import org.springmodules.validation.valang.predicates.Operator.*;
/**
* Translates a collection of valang validation rules into a JavaScript statement
* that is capable of validating a HTML form and writes this to a provided
* Writer. This class is not thread safe so it is recommended
* that a new instance be created each time a translation is required.
*
* The generated JavaScript code is dependent on the code base found in the
* file "valang_codebase.js" having already been loaded into the page where
* the validation will occur.
*
* @author Oliver Hutchison
*/
public class ValangJavaScriptTranslator {
/**
* Returns a Reader for accessing the JavaScript codebase used by the
* translated validation rules.
*/
public static Reader getCodebaseReader() {
return new InputStreamReader(ValangJavaScriptTranslator.class.getResourceAsStream("valang_codebase.js"));
}
private static final Log logger = LogFactory.getLog(ValangJavaScriptTranslator.class);
private static final ReflectiveVisitorHelper reflectiveVisitorHelper = new ReflectiveVisitorHelper();
private Writer writer;
public ValangJavaScriptTranslator() {
}
/**
* Translates the provided set of Valang BasicValidationRules into JavaScript
* code capable of validating a HTML form and outputs the translated code into the provided
* writer.
*
* @param writer the writer to output the JavaScript code into
* @param name the name of the command that is being validated
* @param installSelfWithForm should the generated JavaScript attempt to install
* its self with the form on creation
* @param rules the collection of BasicValidationRules to translate
* @param messageSource the message source accessor that will be used to resolve validation
* messages.
*/
public void writeJavaScriptValangValidator(Writer writer, String name, boolean installSelfWithForm,
Collection rules, MessageSourceAccessor messageSource) throws IOException {
try {
setWriter(writer);
append("new ValangValidator(");
appendJsString(name);
append(',');
append(Boolean.toString(installSelfWithForm));
append(',');
appendArrayValidators(rules, messageSource);
append(')');
}
finally {
clearWriter();
}
}
protected void setWriter(Writer writer) {
Assert.state(this.writer == null,
"Attempted to set writer when one already set - is this class being used is multiple threads?");
this.writer = writer;
}
protected void clearWriter() {
writer = null;
}
protected void append(String string) throws IOException {
writer.write(string);
}
protected void appendJsString(String string) throws IOException {
writer.write('\'');
if (string == null) {
writer.write("null");
} else {
writer.write(JavaScriptUtils.javaScriptEscape(string));
}
writer.write('\'');
}
protected void append(char c) throws IOException {
writer.write(c);
}
private void append(int i) throws IOException {
writer.write(Integer.toString(i));
}
protected void appendArrayValidators(Collection rules, MessageSourceAccessor messageSource) throws IOException {
append("new Array(");
for (Iterator i = rules.iterator(); i.hasNext();) {
appendValidatorRule((BasicValidationRule) i.next(), messageSource);
if (i.hasNext()) {
append(',');
}
}
append(')');
}
protected void appendValidatorRule(BasicValidationRule rule, MessageSourceAccessor messageSource)
throws IOException {
append("new ValangValidator.Rule('");
append(rule.getField());
append("','not implemented',");
appendJsString(getErrorMessage(rule, messageSource));
append(',');
appendValidationFunction(rule.getPredicate());
append(')');
}
protected String getErrorMessage(BasicValidationRule rule, MessageSourceAccessor messageSource) {
if (StringUtils.hasLength(rule.getErrorKey())) {
if (rule.getErrorArgs() != null && !rule.getErrorArgs().isEmpty()) {
// TODO: implement message arguments in JavaScript
logger.warn("Translating error message with arguments is not implemented; using default message");
return rule.getErrorMessage();
} else {
return messageSource.getMessage(rule.getErrorKey(), rule.getErrorMessage());
}
} else {
return rule.getErrorMessage();
}
}
protected void appendValidationFunction(Predicate p) throws IOException {
append("function() {return ");
doVisit(p);
append('}');
}
protected void doVisit(Object value) throws IOException {
reflectiveVisitorHelper.invokeVisit(this, value);
}
void visitNull() throws IOException {
append("null");
}
void visit(Function f) throws IOException {
if (logger.isWarnEnabled()) {
logger.warn("Encountered unsupported custom function '" + f.getClass().getName() + "'");
}
append("this._throwError('don\\'t know how to handle custom function \\'");
append(getNameForCustomFunction(f));
append("\\'')");
}
void visit(AbstractFunction f) throws IOException {
Function[] arguments = f.getArguments();
append(getNameForCustomFunction(f));
append('(');
for (int i = 0; i < arguments.length; i++) {
doVisit(arguments[i]);
if (i < arguments.length - 1) {
append(',');
}
}
append(')');
}
protected String getNameForCustomFunction(Function f) {
return "this." + ClassUtils.getShortName(f.getClass());
}
void visit(NotPredicate p) throws IOException {
Assert.isTrue(p.getPredicates().length == 1);
append("! (");
doVisit(p.getPredicates()[0]);
append(')');
}
void visit(AndPredicate p) throws IOException {
String op = ") && ";
for (int i = 0; i < p.getPredicates().length; i++) {
Predicate innerP = p.getPredicates()[i];
append('(');
doVisit(innerP);
if (i < p.getPredicates().length - 1) {
append(op);
} else {
append(')');
}
}
}
void visit(OrPredicate p) throws IOException {
String op = ") || ";
for (int i = 0; i < p.getPredicates().length; i++) {
Predicate innerP = p.getPredicates()[i];
append('(');
doVisit(innerP);
if (i < p.getPredicates().length - 1) {
append(op);
} else {
append(')');
}
}
}
void visit(GenericTestPredicate p) throws IOException {
append(operatorToFunctionName(p.getOperator()));
append("((");
doVisit(p.getLeftFunction());
append("), (");
doVisit(p.getRightFunction());
append("))");
}
protected String operatorToFunctionName(Operator operator) {
if (operator instanceof EqualsOperator) {
return "this.equals";
} else if (operator instanceof NotEqualsOperator) {
return "! this.equals";
} else if (operator instanceof LessThanOperator) {
return "this.lessThan";
} else if (operator instanceof LessThanOrEqualOperator) {
return "this.lessThanOrEquals";
} else if (operator instanceof MoreThanOperator) {
return "this.moreThan";
} else if (operator instanceof MoreThanOrEqualOperator) {
return "this.moreThanOrEquals";
} else if (operator instanceof InOperator) {
return "this.inFunc";
} else if (operator instanceof NotInOperator) {
return "! this.inFunc";
} else if (operator instanceof BetweenOperator) {
return "this.between";
} else if (operator instanceof NotBetweenOperator) {
return "! this.between";
} else if (operator instanceof NullOperator) {
return "this.nullFunc";
} else if (operator instanceof NotNullOperator) {
return "! this.nullFunc";
} else if (operator instanceof HasTextOperator) {
return "this.hasText";
} else if (operator instanceof HasNoTextOperator) {
return "! this.hasText";
} else if (operator instanceof HasLengthOperator) {
return "this.hasLength";
} else if (operator instanceof HasNoLengthOperator) {
return "! this.hasLength";
} else if (operator instanceof IsBlankOperator) {
return "this.isBlank";
} else if (operator instanceof IsNotBlankOperator) {
return "! this.isBlank";
} else if (operator instanceof IsWordOperator) {
return "this.isWord";
} else if (operator instanceof IsNotWordOperator) {
return "! this.isWord";
} else if (operator instanceof IsUpperCaseOperator) {
return "this.isUpper";
} else if (operator instanceof IsNotUpperCaseOperator) {
return "! this.isUpper";
} else if (operator instanceof IsLowerCaseOperator) {
return "this.isLower";
} else if (operator instanceof IsNotLowerCaseOperator) {
return "! this.isLower";
} else {
throw new UnsupportedOperationException("Unexpected operator type '" + operator.getClass().getName() + "'");
}
}
void visit(TargetBeanFunction f) throws IOException {
append("this.getTargetBean()");
}
void visit(BeanPropertyFunction f) throws IOException {
append("this.getPropertyValue(");
appendJsString(f.getField());
append(')');
}
void visit(MapEntryFunction f) throws IOException {
append("(");
doVisit(f.getMapFunction());
append("[");
doVisit(f.getKeyFunction());
append("])");
}
void visit(LiteralFunction f) throws IOException {
Object literal = f.getResult(null);
if (literal instanceof String) {
appendJsString((String) literal);
} else if (literal instanceof Number) {
append(literal.toString());
} else if (literal instanceof Boolean) {
append(literal.toString());
} else if (literal instanceof Function[]) {
Function[] functions = (Function[]) literal;
appeandLiteralArray(functions);
} else if (literal instanceof Collection) {
appeandLiteralArray((((Collection) literal).toArray()));
} else {
throw new UnsupportedOperationException("Unexpected literal type '" + literal.getClass() + "'");
}
}
void appeandLiteralArray(Object[] functions) throws IOException {
append("new Array(");
for (int i = 0; i < functions.length; i++) {
doVisit(functions[i]);
if (i < functions.length - 1) {
append(",");
}
}
append(')');
}
void visit(DateLiteralFunction f) throws IOException {
Calendar cal = Calendar.getInstance();
cal.setTime((Date) f.getResult(null));
append("new Date(");
append(cal.get(Calendar.YEAR));
append(", ");
append(cal.get(Calendar.MONTH));
append(", ");
append(cal.get(Calendar.DATE));
append(", ");
append(cal.get(Calendar.HOUR_OF_DAY));
append(", ");
append(cal.get(Calendar.MINUTE));
append(", ");
append(cal.get(Calendar.SECOND));
append(", ");
append(cal.get(Calendar.MILLISECOND));
append(')');
}
void visit(LengthOfFunction f) throws IOException {
append("this.lengthOf(");
doVisit(f.getArguments()[0]);
append(')');
}
void visit(NotFunction f) throws IOException {
append("! ");
doVisit(f.getArguments()[0]);
}
void visit(UpperCaseFunction f) throws IOException {
append("this.upperCase(");
doVisit(f.getArguments()[0]);
append(')');
}
void visit(LowerCaseFunction f) throws IOException {
append("this.lowerCase(");
doVisit(f.getArguments()[0]);
append(')');
}
void visit(AbstractMathFunction f) throws IOException {
append(mathToFunctionName(f));
append("((");
doVisit(f.getLeftFunction());
append("),(");
doVisit(f.getRightFunction());
append("))");
}
protected String mathToFunctionName(AbstractMathFunction f) {
if (f instanceof AddFunction) {
return "this.add";
} else if (f instanceof DivideFunction) {
return "this.divide";
} else if (f instanceof ModuloFunction) {
return "this.modulo";
} else if (f instanceof MultiplyFunction) {
return "this.multiply";
} else if (f instanceof SubtractFunction) {
return "this.subtract";
} else {
throw new UnsupportedOperationException("Unexpected math function type '" + f.getClass().getName() + "'");
}
}
}