org.apache.camel.component.gson.GsonDataFormat Maven / Gradle / Ivy
/*
* 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.camel.component.gson;
import java.io.BufferedReader;
import java.io.BufferedWriter;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.io.OutputStream;
import java.io.OutputStreamWriter;
import java.lang.reflect.Type;
import java.util.Arrays;
import java.util.List;
import com.google.gson.ExclusionStrategy;
import com.google.gson.FieldNamingPolicy;
import com.google.gson.FieldNamingStrategy;
import com.google.gson.Gson;
import com.google.gson.GsonBuilder;
import com.google.gson.LongSerializationPolicy;
import org.apache.camel.CamelContext;
import org.apache.camel.CamelContextAware;
import org.apache.camel.Exchange;
import org.apache.camel.spi.DataFormat;
import org.apache.camel.spi.DataFormatContentTypeHeader;
import org.apache.camel.spi.DataFormatName;
import org.apache.camel.spi.Metadata;
import org.apache.camel.spi.annotations.Dataformat;
import org.apache.camel.support.ExchangeHelper;
import org.apache.camel.support.service.ServiceSupport;
import org.apache.camel.util.IOHelper;
/**
* Marshal POJOs to JSON and back using Gson
*/
@Dataformat("gson")
@Metadata(includeProperties = "unmarshalType,unmarshalTypeName,prettyPrint,dateFormatPattern,contentTypeHeader")
public class GsonDataFormat extends ServiceSupport
implements DataFormat, DataFormatName, DataFormatContentTypeHeader, CamelContextAware {
private CamelContext camelContext;
private Gson gson;
private Class unmarshalType;
private String unmarshalTypeName;
private Type unmarshalGenericType;
private List exclusionStrategies;
private LongSerializationPolicy longSerializationPolicy;
private FieldNamingPolicy fieldNamingPolicy;
private FieldNamingStrategy fieldNamingStrategy;
private boolean serializeNulls;
private boolean prettyPrint;
private String dateFormatPattern;
private boolean contentTypeHeader = true;
public GsonDataFormat() {
this(Object.class);
}
/**
* Use the default Gson {@link Gson} and with a custom unmarshal type
*
* @param unmarshalType the custom unmarshal type
*/
public GsonDataFormat(Class unmarshalType) {
this(null, unmarshalType);
}
/**
* Use the default Gson {@link Gson} and with a custom unmarshal type and {@link ExclusionStrategy}
*
* @param unmarshalType the custom unmarshal type
* @param exclusionStrategies one or more custom ExclusionStrategy implementations
* @deprecated use the setter instead
*/
@Deprecated
public GsonDataFormat(Class unmarshalType, ExclusionStrategy... exclusionStrategies) {
this(null, unmarshalType);
setExclusionStrategies(Arrays.asList(exclusionStrategies));
}
/**
* Use a custom Gson mapper and and unmarshal type
*
* @param gson the custom mapper
* @param unmarshalType the custom unmarshal type
*/
public GsonDataFormat(Gson gson, Class unmarshalType) {
this.gson = gson;
this.unmarshalType = unmarshalType;
}
/**
* Use the default Gson {@link Gson} and with a custom unmarshal generic type
*
* @param unmarshalGenericType the custom unmarshal generic type
*/
public GsonDataFormat(Type unmarshalGenericType) {
this(null, unmarshalGenericType);
}
/**
* Use a custom Gson mapper and and unmarshal token type
*
* @param gson the custom mapper
* @param unmarshalGenericType the custom unmarshal generic type
*/
public GsonDataFormat(Gson gson, Type unmarshalGenericType) {
this.gson = gson;
this.unmarshalGenericType = unmarshalGenericType;
}
@Override
public CamelContext getCamelContext() {
return camelContext;
}
@Override
public void setCamelContext(CamelContext camelContext) {
this.camelContext = camelContext;
}
@Override
public String getDataFormatName() {
return "gson";
}
@Override
public void marshal(final Exchange exchange, final Object graph, final OutputStream stream) throws Exception {
try (final OutputStreamWriter osw = new OutputStreamWriter(stream, ExchangeHelper.getCharsetName(exchange));
final BufferedWriter writer = IOHelper.buffered(osw)) {
gson.toJson(graph, writer);
}
if (contentTypeHeader) {
exchange.getMessage().setHeader(Exchange.CONTENT_TYPE, "application/json");
}
}
@Override
public Object unmarshal(final Exchange exchange, final InputStream stream) throws Exception {
try (final InputStreamReader isr = new InputStreamReader(stream, ExchangeHelper.getCharsetName(exchange));
final BufferedReader reader = IOHelper.buffered(isr)) {
String type = exchange.getIn().getHeader(GsonConstants.UNMARSHAL_TYPE, String.class);
if (type != null) {
Class clazz = exchange.getContext().getClassResolver().resolveMandatoryClass(type);
return gson.fromJson(reader, clazz);
} else if (unmarshalGenericType == null) {
return gson.fromJson(reader, unmarshalType);
} else {
return gson.fromJson(reader, unmarshalGenericType);
}
}
}
@Override
protected void doInit() throws Exception {
if (unmarshalTypeName != null && (unmarshalType == null || unmarshalType == Object.class)) {
unmarshalType = camelContext.getClassResolver().resolveClass(unmarshalTypeName);
}
}
@Override
protected void doStart() throws Exception {
if (gson == null) {
GsonBuilder builder = new GsonBuilder();
if (exclusionStrategies != null && !exclusionStrategies.isEmpty()) {
ExclusionStrategy[] strategies = exclusionStrategies.toArray(new ExclusionStrategy[exclusionStrategies.size()]);
builder.setExclusionStrategies(strategies);
}
if (longSerializationPolicy != null) {
builder.setLongSerializationPolicy(longSerializationPolicy);
}
if (fieldNamingPolicy != null) {
builder.setFieldNamingPolicy(fieldNamingPolicy);
}
if (fieldNamingStrategy != null) {
builder.setFieldNamingStrategy(fieldNamingStrategy);
}
if (serializeNulls) {
builder.serializeNulls();
}
if (prettyPrint) {
builder.setPrettyPrinting();
}
if (dateFormatPattern != null) {
builder.setDateFormat(dateFormatPattern);
}
gson = builder.create();
}
}
@Override
protected void doStop() throws Exception {
// noop
}
// Properties
// -------------------------------------------------------------------------
public Class getUnmarshalType() {
return this.unmarshalType;
}
public void setUnmarshalType(Class unmarshalType) {
this.unmarshalType = unmarshalType;
}
public String getUnmarshalTypeName() {
return unmarshalTypeName;
}
public void setUnmarshalTypeName(String unmarshalTypeName) {
this.unmarshalTypeName = unmarshalTypeName;
}
public Type getUnmarshalGenericType() {
return this.unmarshalType;
}
public void setUnmarshalGenericType(Type unmarshalGenericType) {
this.unmarshalGenericType = unmarshalGenericType;
}
public List getExclusionStrategies() {
return exclusionStrategies;
}
public void setExclusionStrategies(List exclusionStrategies) {
this.exclusionStrategies = exclusionStrategies;
}
public LongSerializationPolicy getLongSerializationPolicy() {
return longSerializationPolicy;
}
public void setLongSerializationPolicy(LongSerializationPolicy longSerializationPolicy) {
this.longSerializationPolicy = longSerializationPolicy;
}
public FieldNamingPolicy getFieldNamingPolicy() {
return fieldNamingPolicy;
}
public void setFieldNamingPolicy(FieldNamingPolicy fieldNamingPolicy) {
this.fieldNamingPolicy = fieldNamingPolicy;
}
public FieldNamingStrategy getFieldNamingStrategy() {
return fieldNamingStrategy;
}
public void setFieldNamingStrategy(FieldNamingStrategy fieldNamingStrategy) {
this.fieldNamingStrategy = fieldNamingStrategy;
}
/**
* @deprecated use {@link #isSerializeNulls()} instead
*/
@Deprecated
public Boolean getSerializeNulls() {
return serializeNulls;
}
public boolean isSerializeNulls() {
return serializeNulls;
}
/**
* @deprecated use {@link #setSerializeNulls(boolean)} instead
*/
@Deprecated
public void setSerializeNulls(Boolean serializeNulls) {
this.serializeNulls = serializeNulls;
}
public void setSerializeNulls(boolean serializeNulls) {
this.serializeNulls = serializeNulls;
}
/**
* @deprecated use {@link #isPrettyPrint()} instead
*/
@Deprecated
public Boolean getPrettyPrinting() {
return prettyPrint;
}
public boolean isPrettyPrint() {
return prettyPrint;
}
/**
* @deprecated use {@link #setPrettyPrint(boolean)} instead
*/
@Deprecated
public void setPrettyPrinting(Boolean prettyPrinting) {
this.prettyPrint = prettyPrinting;
}
public void setPrettyPrint(boolean prettyPrint) {
this.prettyPrint = prettyPrint;
}
public String getDateFormatPattern() {
return dateFormatPattern;
}
public void setDateFormatPattern(String dateFormatPattern) {
this.dateFormatPattern = dateFormatPattern;
}
public boolean isContentTypeHeader() {
return contentTypeHeader;
}
/**
* If enabled then Gson will set the Content-Type header to application/json when marshalling.
*/
public void setContentTypeHeader(boolean contentTypeHeader) {
this.contentTypeHeader = contentTypeHeader;
}
public Gson getGson() {
return this.gson;
}
}