/*
* Copyright 2005 Joe Walker
*
* 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.directwebremoting.convert;
import java.lang.reflect.Modifier;
import java.util.HashMap;
import java.util.Map;
import java.util.Map.Entry;
import java.util.StringTokenizer;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.directwebremoting.ConversionException;
import org.directwebremoting.extend.ConvertUtil;
import org.directwebremoting.extend.Converter;
import org.directwebremoting.extend.ConverterManager;
import org.directwebremoting.extend.InboundContext;
import org.directwebremoting.extend.InboundVariable;
import org.directwebremoting.extend.ObjectOutboundVariable;
import org.directwebremoting.extend.OutboundContext;
import org.directwebremoting.extend.OutboundVariable;
import org.directwebremoting.extend.Property;
import org.directwebremoting.extend.ProtocolConstants;
import org.directwebremoting.util.JavascriptUtil;
import org.directwebremoting.util.LocalUtil;
/**
* An implementation of Converter for Maps.
* @author Joe Walker [joe at getahead dot ltd dot uk]
*/
public class MapConverter implements Converter
{
/* (non-Javadoc)
* @see org.directwebremoting.Converter#setConverterManager(org.directwebremoting.ConverterManager)
*/
public void setConverterManager(ConverterManager converterManager)
{
this.converterManager = converterManager;
}
/* (non-Javadoc)
* @see org.directwebremoting.Converter#convertInbound(java.lang.Class, org.directwebremoting.InboundVariable, org.directwebremoting.InboundContext)
*/
@SuppressWarnings("unchecked")
public Object convertInbound(Class<?> paramType, InboundVariable data) throws ConversionException
{
if (data.isNull())
{
return null;
}
String value = data.getValue();
// If the text is null then the whole bean is null
if (value.trim().equals(ProtocolConstants.INBOUND_NULL))
{
return null;
}
if (!value.startsWith(ProtocolConstants.INBOUND_MAP_START) || !value.endsWith(ProtocolConstants.INBOUND_MAP_END))
{
log.warn("Expected object while converting data for " + paramType.getName() + " in " + data.getContext().getCurrentProperty() + ". Passed: " + value);
throw new ConversionException(paramType, "Data conversion error. See logs for more details.");
}
value = value.substring(1, value.length() - 1);
try
{
// Maybe we ought to check that the paramType isn't expecting a more
// distinct type of Map and attempt to create that?
Map<Object, Object> map;
// If paramType is concrete then just use whatever we've got.
if (!paramType.isInterface() && !Modifier.isAbstract(paramType.getModifiers()))
{
// If there is a problem creating the type then we have no way
// of completing this - they asked for a specific type and we
// can't create that type. I don't know of a way of finding
// subclasses that might be instaniable so we accept failure.
map = (Map<Object, Object>) paramType.newInstance();
}
else
{
map = new HashMap<Object, Object>();
}
// Get the extra type info
Property parent = data.getContext().getCurrentProperty();
Property keyProp = parent.createChild(0);
keyProp = converterManager.checkOverride(keyProp);
Class<?> keyType = keyProp.getPropertyType();
Property valProp = parent.createChild(1);
valProp = converterManager.checkOverride(valProp);
Class<?> valType = valProp.getPropertyType();
// We should put the new object into the working map in case it
// is referenced later nested down in the conversion process.
data.getContext().addConverted(data, paramType, map);
InboundContext incx = data.getContext();
// Loop through the property declarations
StringTokenizer st = new StringTokenizer(value, ",");
int size = st.countTokens();
for (int i = 0; i < size; i++)
{
String token = st.nextToken();
if (token.trim().length() == 0)
{
continue;
}
int colonpos = token.indexOf(ProtocolConstants.INBOUND_MAP_ENTRY);
if (colonpos == -1)
{
throw new ConversionException(paramType, "Missing " + ProtocolConstants.INBOUND_MAP_ENTRY + " in object description: {1}" + token);
}
// Convert the value part of the token by splitting it into the
// type and value (as passed in by Javascript)
String valStr = token.substring(colonpos + 1).trim();
String[] splitIv = ConvertUtil.splitInbound(valStr);
String splitIvValue = splitIv[ConvertUtil.INBOUND_INDEX_VALUE];
String splitIvType = splitIv[ConvertUtil.INBOUND_INDEX_TYPE];
InboundVariable valIv = new InboundVariable(incx, null, splitIvType, splitIvValue);
valIv.dereference();
Object val = converterManager.convertInbound(valType, valIv, valProp);
// Keys (unlike values) do not have type info passed with them
// Could we have recursive key? - I don't think so because keys
// must be strings in Javascript
String keyStr = token.substring(0, colonpos).trim();
//String[] keySplit = LocalUtil.splitInbound(keyStr);
//InboundVariable keyIv = new InboundVariable(incx, splitIv[LocalUtil.INBOUND_INDEX_TYPE], splitIv[LocalUtil.INBOUND_INDEX_VALUE]);
InboundVariable keyIv = new InboundVariable(incx, null, ProtocolConstants.TYPE_STRING, keyStr);
keyIv.dereference();
Object key = converterManager.convertInbound(keyType, keyIv, keyProp);
map.put(key, val);
}
return map;
}
catch (ConversionException ex)
{
throw ex;
}
catch (Exception ex)
{
throw new ConversionException(paramType, ex);
}
}
/* (non-Javadoc)
* @see org.directwebremoting.Converter#convertOutbound(java.lang.Object, org.directwebremoting.OutboundContext)
*/
@SuppressWarnings("unchecked")
public OutboundVariable convertOutbound(Object data, OutboundContext outctx) throws ConversionException
{
// First we just collect our converted children
//noinspection unchecked
Map<String, OutboundVariable> ovs = LocalUtil.classNewInstance("OrderedConvertOutbound", "java.util.LinkedHashMap", Map.class);
if (ovs == null)
{
ovs = new HashMap<String, OutboundVariable>();
}
ObjectOutboundVariable ov = new ObjectOutboundVariable(outctx);
outctx.put(data, ov);
// Loop through the map outputting any init code and collecting
// converted outbound variables into the ovs map
Map<Object, Object> map = (Map<Object, Object>) data;
for (Entry<Object, Object> entry : map.entrySet())
{
Object key = entry.getKey();
Object value = entry.getValue();
// If the key is null, retrieve the configured null key value from the configuration of this converter.
if (null == key && null != nullKey) {
log.debug("MapConverter: A null key was encountered DWR is using the configured nullKey string: " + nullKey);
key = nullKey;
}
// It would be nice to check for Enums here
if (!(key instanceof String) && !sentNonStringWarning)
{
log.warn("--Javascript does not support non string keys. Converting '" + key.getClass().getName() + "' using toString()");
sentNonStringWarning = true;
}
String outkey = JavascriptUtil.escapeJavaScript(key.toString());
/*
OutboundVariable ovkey = converterManager.convertOutbound(key, outctx);
buffer.append(ovkey.getInitCode());
outkey = ovkey.getAssignCode();
*/
OutboundVariable nested = converterManager.convertOutbound(value, outctx);
ovs.put(outkey, nested);
}
ov.setChildren(ovs);
return ov;
}
/**
* @return the nullKey
*/
public String getNullKey()
{
return nullKey;
}
/**
* @param nullKey the nullKey to set
*/
public void setNullKey(String nullKey)
{
this.nullKey = nullKey;
}
/**
* We don't want to give the non-string warning too many times.
*/
private static boolean sentNonStringWarning = false;
/**
* To forward marshalling requests
*/
private ConverterManager converterManager = null;
/**
* Used by DWR if a null key is encountered. Configure in the init section when the map converter is declared.
* <converter id="map" class="org.directwebremoting.convert.MapConverter">
* <param name="nullKey" value="null" />
* </converter>
*/
private String nullKey = null;
/**
* The log stream
*/
private static final Log log = LogFactory.getLog(MapConverter.class);
}