org.codehaus.jackson.map.ext.OptionalHandlerFactory Maven / Gradle / Ivy
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Data Mapper package is a high-performance data binding package
built on Jackson JSON processor
package org.codehaus.jackson.map.ext;
import java.util.Collection;
import java.util.Map;
import org.codehaus.jackson.map.*;
import org.codehaus.jackson.map.deser.StdDeserializer;
import org.codehaus.jackson.map.introspect.BasicBeanDescription;
import org.codehaus.jackson.map.util.Provider;
import org.codehaus.jackson.type.JavaType;
/**
* Helper class used for isolating details of handling optional+external types (Joda datetime,
* javax.xml classes) from standard factories that offer them.
*
* @author tatu
*
* @since 1.6.1
*/
public class OptionalHandlerFactory
{
/* 1.6.1+ To make 2 main "optional" handler groups (javax.xml.stream, Joda date/time)
* more dynamic, we better only figure out handlers completely dynamically, if and
* when they are needed. To do this we need to assume package prefixes.
*/
private final static String PACKAGE_PREFIX_JODA_DATETIME = "org.joda.time.";
private final static String PACKAGE_PREFIX_JAVAX_XML = "javax.xml.";
private final static String SERIALIZERS_FOR_JODA_DATETIME = "org.codehaus.jackson.map.ext.JodaSerializers";
private final static String SERIALIZERS_FOR_JAVAX_XML = "org.codehaus.jackson.map.ext.CoreXMLSerializers";
private final static String DESERIALIZERS_FOR_JODA_DATETIME = "org.codehaus.jackson.map.ext.JodaDeserializers";
private final static String DESERIALIZERS_FOR_JAVAX_XML = "org.codehaus.jackson.map.ext.CoreXMLDeserializers";
// Plus we also have a single serializer for DOM Node:
private final static String CLASS_NAME_DOM_NODE = "org.w3c.dom.Node";
private final static String CLASS_NAME_DOM_DOCUMENT = "org.w3c.dom.Node";
private final static String SERIALIZER_FOR_DOM_NODE = "org.codehaus.jackson.map.ext.DOMSerializer";
private final static String DESERIALIZER_FOR_DOM_DOCUMENT = "org.codehaus.jackson.map.ext.DOMDeserializer$DocumentDeserializer";
private final static String DESERIALIZER_FOR_DOM_NODE = "org.codehaus.jackson.map.ext.DOMDeserializer$NodeDeserializer";
public final static OptionalHandlerFactory instance = new OptionalHandlerFactory();
protected OptionalHandlerFactory() { }
/*
/**********************************************************
/* Public API
/**********************************************************
*/
public JsonSerializer findSerializer(JavaType type, SerializationConfig config,
BasicBeanDescription beanInfo)
{
Class rawType = type.getRawClass();
String className = rawType.getName();
String factoryName;
if (className.startsWith(PACKAGE_PREFIX_JODA_DATETIME)) {
factoryName = SERIALIZERS_FOR_JODA_DATETIME;
} else if (className.startsWith(PACKAGE_PREFIX_JAVAX_XML)
|| hasSupertypeStartingWith(rawType, PACKAGE_PREFIX_JAVAX_XML)) {
factoryName = SERIALIZERS_FOR_JAVAX_XML;
} else if (doesImplement(rawType, CLASS_NAME_DOM_NODE)) {
return (JsonSerializer) instantiate(SERIALIZER_FOR_DOM_NODE);
} else {
return null;
}
Object ob = instantiate(factoryName);
if (ob == null) { // could warn, if we had logging system (j.u.l?)
return null;
}
@SuppressWarnings("unchecked")
Provider,JsonSerializer>> prov = (Provider,JsonSerializer>>) ob;
Collection,JsonSerializer>> entries = prov.provide();
// first, check for exact match (concrete)
for (Map.Entry,JsonSerializer> entry : entries) {
if (rawType == entry.getKey()) {
return entry.getValue();
}
}
// if no match, check super-type match
for (Map.Entry,JsonSerializer> entry : entries) {
if (entry.getKey().isAssignableFrom(rawType)) {
return entry.getValue();
}
}
// but maybe there's just no match to be found?
return null;
}
public JsonDeserializer findDeserializer(JavaType type, DeserializationConfig config, DeserializerProvider p)
{
Class rawType = type.getRawClass();
String className = rawType.getName();
String factoryName;
if (className.startsWith(PACKAGE_PREFIX_JODA_DATETIME)) {
factoryName = DESERIALIZERS_FOR_JODA_DATETIME;
} else if (className.startsWith(PACKAGE_PREFIX_JAVAX_XML)
|| hasSupertypeStartingWith(rawType, PACKAGE_PREFIX_JAVAX_XML)) {
factoryName = DESERIALIZERS_FOR_JAVAX_XML;
} else if (doesImplement(rawType, CLASS_NAME_DOM_DOCUMENT)) {
return (JsonDeserializer) instantiate(DESERIALIZER_FOR_DOM_DOCUMENT);
} else if (doesImplement(rawType, CLASS_NAME_DOM_NODE)) {
return (JsonDeserializer) instantiate(DESERIALIZER_FOR_DOM_NODE);
} else {
return null;
}
Object ob = instantiate(factoryName);
if (ob == null) { // could warn, if we had logging system (j.u.l?)
return null;
}
@SuppressWarnings("unchecked")
Provider> prov = (Provider>) ob;
Collection> entries = prov.provide();
// first, check for exact match (concrete)
for (StdDeserializer deser : entries) {
if (rawType == deser.getValueClass()) {
return deser;
}
}
// if no match, check super-type match
for (StdDeserializer deser : entries) {
if (deser.getValueClass().isAssignableFrom(rawType)) {
return deser;
}
}
// but maybe there's just no match to be found?
return null;
}
/*
/**********************************************************
/* Internal helper methods
/**********************************************************
*/
private Object instantiate(String className)
{
try {
return Class.forName(className).newInstance();
}
catch (LinkageError e) { }
// too many different kinds to enumerate here:
catch (Exception e) { }
return null;
}
private boolean doesImplement(Class actualType, String classNameToImplement)
{
for (Class type = actualType; type != null; type = type.getSuperclass()) {
if (type.getName().equals(classNameToImplement)) {
return true;
}
// or maybe one of super-interfaces
if (hasInterface(type, classNameToImplement)) {
return true;
}
}
return false;
}
private boolean hasInterface(Class type, String interfaceToImplement)
{
Class[] interfaces = type.getInterfaces();
for (Class iface : interfaces) {
if (iface.getName().equals(interfaceToImplement)) {
return true;
}
}
// maybe super-interface?
for (Class iface : interfaces) {
if (hasInterface(iface, interfaceToImplement)) {
return true;
}
}
return false;
}
private boolean hasSupertypeStartingWith(Class rawType, String prefix)
{
// first, superclasses
for (Class supertype = rawType.getSuperclass(); supertype != null; supertype = supertype.getSuperclass()) {
if (supertype.getName().startsWith(prefix)) {
return true;
}
}
// then interfaces
for (Class cls = rawType; cls != null; cls = cls.getSuperclass()) {
if (hasInterfaceStartingWith(cls, prefix)) {
return true;
}
}
return false;
}
private boolean hasInterfaceStartingWith(Class type, String prefix)
{
Class[] interfaces = type.getInterfaces();
for (Class iface : interfaces) {
if (iface.getName().startsWith(prefix)) {
return true;
}
}
// maybe super-interface?
for (Class iface : interfaces) {
if (hasInterfaceStartingWith(iface, prefix)) {
return true;
}
}
return false;
}
}