XWorkBasicConverter.java
/*
* 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.struts2.conversion.impl;
import org.apache.struts2.conversion.TypeConverter;
import org.apache.struts2.inject.Container;
import org.apache.struts2.inject.Inject;
import org.apache.struts2.StrutsConstants;
import org.apache.struts2.conversion.TypeConversionException;
import java.lang.reflect.Member;
import java.time.LocalDate;
import java.time.LocalDateTime;
import java.time.LocalTime;
import java.time.OffsetDateTime;
import java.util.Calendar;
import java.util.Collection;
import java.util.Date;
import java.util.Map;
/**
* <!-- START SNIPPET: javadoc -->
* <p>
* XWork will automatically handle the most common type conversion for you. This includes support for converting to
* and from Strings for each of the following:
* </p>
*
* <ul>
* <li>String</li>
* <li>boolean / Boolean</li>
* <li>char / Character</li>
* <li>int / Integer, float / Float, long / Long, double / Double</li>
* <li>dates - uses the SHORT format for the Locale associated with the current request</li>
* <li>arrays - assuming the individual strings can be coverted to the individual items</li>
* <li>collections - if not object type can be determined, it is assumed to be a String and a new ArrayList is
* created</li>
* </ul>
*
* <p> Note that with arrays the type conversion will defer to the type of the array elements and try to convert each
* item individually. As with any other type conversion, if the conversion can't be performed the standard type
* conversion error reporting is used to indicate a problem occurred while processing the type conversion.
* </p>
*
* <!-- END SNIPPET: javadoc -->
*
* @author <a href="mailto:plightbo@gmail.com">Pat Lightbody</a>
* @author Mike Mosiewicz
* @author Rainer Hermanns
* @author <a href='mailto:the_mindstorm[at]evolva[dot]ro'>Alexandru Popescu</a>
*/
public class XWorkBasicConverter extends DefaultTypeConverter {
private Container container;
@Inject
public void setContainer(Container container) {
this.container = container;
}
@Override
public Object convertValue(Map<String, Object> context, Object o, Member member, String propertyName, Object value, Class toType) {
Object result = null;
if (value == null || toType.isAssignableFrom(value.getClass())) {
// no need to convert at all, right?
return value;
}
if (toType == String.class) {
/* the code below has been disabled as it causes sideffects in Struts2 (XW-512)
// if input (value) is a number then use special conversion method (XW-490)
Class inputType = value.getClass();
if (Number.class.isAssignableFrom(inputType)) {
result = doConvertFromNumberToString(context, value, inputType);
if (result != null) {
return result;
}
}*/
// okay use default string conversion
result = doConvertToString(context, value);
} else if (toType == boolean.class) {
result = doConvertToBoolean(value);
} else if (toType == Boolean.class) {
result = doConvertToBoolean(value);
} else if (toType.isArray()) {
result = doConvertToArray(context, o, member, propertyName, value, toType);
} else if (Date.class.isAssignableFrom(toType)) {
result = doConvertToDate(context, value, toType);
} else if (LocalDate.class.isAssignableFrom(toType)) {
result = doConvertToDate(context, value, toType);
} else if (LocalDateTime.class.isAssignableFrom(toType)) {
result = doConvertToDate(context, value, toType);
} else if (LocalTime.class.isAssignableFrom(toType)) {
result = doConvertToDate(context, value, toType);
} else if (OffsetDateTime.class.isAssignableFrom(toType)) {
result = doConvertToDate(context, value, toType);
} else if (Calendar.class.isAssignableFrom(toType)) {
result = doConvertToCalendar(context, value);
} else if (Collection.class.isAssignableFrom(toType)) {
result = doConvertToCollection(context, o, member, propertyName, value, toType);
} else if (toType == Character.class) {
result = doConvertToCharacter(value);
} else if (toType == char.class) {
result = doConvertToCharacter(value);
} else if (Number.class.isAssignableFrom(toType) || toType.isPrimitive()) {
result = doConvertToNumber(context, value, toType);
} else if (toType == Class.class) {
result = doConvertToClass(value);
}
if (result == null) {
if (value instanceof Object[] array) {
if (array.length >= 1) {
value = array[0];
} else {
value = null;
}
// let's try to convert the first element only
result = convertValue(context, o, member, propertyName, value, toType);
} else if (!"".equals(value)) { // we've already tried the types we know
result = super.convertValue(context, value, toType);
}
if (result == null && value != null && !"".equals(value)) {
throw new TypeConversionException("Cannot create type " + toType + " from value " + value);
}
}
return result;
}
private Object doConvertToCalendar(Map<String, Object> context, Object value) {
Object result = null;
Date dateResult = (Date) doConvertToDate(context, value, Date.class);
if (dateResult != null) {
Calendar calendar = Calendar.getInstance();
calendar.setTime(dateResult);
result = calendar;
}
return result;
}
private Object doConvertToCharacter(Object value) {
if (value instanceof String cStr) {
return !cStr.isEmpty() ? cStr.charAt(0) : null;
}
return null;
}
private Object doConvertToBoolean(Object value) {
if (value instanceof String bStr) {
return Boolean.valueOf(bStr);
}
return null;
}
private Class doConvertToClass(Object value) {
Class clazz = null;
if (value instanceof String st && !st.isEmpty()) {
try {
clazz = Class.forName(st);
} catch (ClassNotFoundException e) {
throw new TypeConversionException(e.getLocalizedMessage(), e);
}
}
return clazz;
}
private Object doConvertToCollection(Map<String, Object> context, Object o, Member member, String prop, Object value, Class toType) {
TypeConverter converter = container.getInstance(CollectionConverter.class);
if (converter == null) {
throw new TypeConversionException("TypeConverter with name [#0] must be registered first! Converter: "+ StrutsConstants.STRUTS_CONVERTER_COLLECTION);
}
return converter.convertValue(context, o, member, prop, value, toType);
}
private Object doConvertToArray(Map<String, Object> context, Object o, Member member, String prop, Object value, Class toType) {
TypeConverter converter = container.getInstance(ArrayConverter.class);
if (converter == null) {
throw new TypeConversionException("TypeConverter with name [#0] must be registered first! Converter: "+ StrutsConstants.STRUTS_CONVERTER_ARRAY);
}
return converter.convertValue(context, o, member, prop, value, toType);
}
private Object doConvertToDate(Map<String, Object> context, Object value, Class toType) {
TypeConverter converter = container.getInstance(DateConverter.class);
if (converter == null) {
throw new TypeConversionException("TypeConverter with name [#0] must be registered first! Converter: "+ StrutsConstants.STRUTS_CONVERTER_DATE);
}
return converter.convertValue(context, null, null, null, value, toType);
}
private Object doConvertToNumber(Map<String, Object> context, Object value, Class toType) {
TypeConverter converter = container.getInstance(NumberConverter.class);
if (converter == null) {
throw new TypeConversionException("TypeConverter with name [#0] must be registered first! Converter: "+ StrutsConstants.STRUTS_CONVERTER_NUMBER);
}
return converter.convertValue(context, null, null, null, value, toType);
}
private Object doConvertToString(Map<String, Object> context, Object value) {
TypeConverter converter = container.getInstance(StringConverter.class);
if (converter == null) {
throw new TypeConversionException("TypeConverter with name [#0] must be registered first! Converter: "+ StrutsConstants.STRUTS_CONVERTER_STRING);
}
return converter.convertValue(context, null, null, null, value, null);
}
}