org.apache.tika.metadata.serialization.JsonMetadata Maven / Gradle / Ivy
package org.apache.tika.metadata.serialization;
/*
* 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.
*/
import java.io.Reader;
import java.io.Writer;
import com.google.gson.Gson;
import com.google.gson.JsonIOException;
import org.apache.tika.exception.TikaException;
import org.apache.tika.metadata.Metadata;
public class JsonMetadata extends JsonMetadataBase{
private static Gson GSON;
static {
GSON = defaultInit();
}
/**
* Serializes a Metadata object to Json. This does not flush or close the writer.
*
* @param metadata metadata to write
* @param writer writer
* @throws TikaException if there is an IOException during writing
*/
public static void toJson(Metadata metadata, Writer writer) throws TikaException {
try {
GSON.toJson(metadata, writer);
} catch (JsonIOException e) {
throw new TikaException(e.getMessage());
}
}
/**
* Read metadata from reader.
*
* @param reader reader to read from
* @return Metadata or null if nothing could be read from the reader
* @throws TikaException in case of parse failure by Gson or IO failure with Reader
*/
public static Metadata fromJson(Reader reader) throws TikaException {
Metadata m = null;
try {
m = GSON.fromJson(reader, Metadata.class);
} catch (com.google.gson.JsonParseException e){
//covers both io and parse exceptions
throw new TikaException(e.getMessage());
}
return m;
}
/**
* Enables setting custom configurations on Gson. Remember to register
* a serializer and a deserializer for Metadata. This does a literal set
* and does not add the default serializer and deserializers.
*
* @param gson
*/
public static void setGson(Gson gson) {
GSON = gson;
}
public static void setPrettyPrinting(boolean prettyPrint) {
if (prettyPrint) {
GSON = prettyInit();
} else {
GSON = defaultInit();
}
}
}