/*
* 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 javax.json.spi;
import javax.json.JsonArrayBuilder;
import javax.json.JsonBuilderFactory;
import javax.json.JsonException;
import javax.json.JsonObjectBuilder;
import javax.json.JsonReader;
import javax.json.JsonReaderFactory;
import javax.json.JsonWriter;
import javax.json.JsonWriterFactory;
import javax.json.stream.JsonGenerator;
import javax.json.stream.JsonGeneratorFactory;
import javax.json.stream.JsonParser;
import javax.json.stream.JsonParserFactory;
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.io.OutputStream;
import java.io.Reader;
import java.io.Writer;
import java.lang.reflect.Method;
import java.net.URL;
import java.security.AccessController;
import java.security.PrivilegedAction;
import java.util.ArrayList;
import java.util.Enumeration;
import java.util.Iterator;
import java.util.List;
import java.util.Map;
import java.util.ServiceLoader;
public abstract class JsonProvider {
private static final String DEFAULT_PROVIDER = "org.apache.fleece.core.JsonProviderImpl";
protected JsonProvider() {
// no-op
}
public static JsonProvider provider() {
if (System.getSecurityManager() != null) {
return AccessController.doPrivileged(new PrivilegedAction<JsonProvider>() {
public JsonProvider run() {
return doLoadProvider();
}
});
}
return doLoadProvider();
}
private static JsonProvider doLoadProvider() throws JsonException {
final ClassLoader tccl = Thread.currentThread().getContextClassLoader();
try {
final Class<?> clazz = Class.forName("org.apache.geronimo.osgi.locator.ProviderLocator");
final Method getServices = clazz.getDeclaredMethod("getServices", String.class, Class.class, ClassLoader.class);
final List<JsonProvider> osgiProviders = (List<JsonProvider>) getServices.invoke(null, JsonProvider.class.getName(), JsonProvider.class, tccl);
if (osgiProviders != null && !osgiProviders.isEmpty()) {
return osgiProviders.iterator().next();
}
} catch (final Throwable e) {
// locator not available, try normal mode
}
// don't use Class.forName() to avoid to bind class to tccl if thats a classloader facade
// so implementing a simple SPI when ProviderLocator is not here
final String name = "META-INF/services/" + JsonProvider.class.getName();
try {
Enumeration<URL> configs;
if (tccl == null) {
configs = ClassLoader.getSystemResources(name);
} else {
configs = tccl.getResources(name);
}
if (configs.hasMoreElements()) {
InputStream in = null;
BufferedReader r = null;
final List<String> names = new ArrayList<String>();
try {
in = configs.nextElement().openStream();
r = new BufferedReader(new InputStreamReader(in, "utf-8"));
String l;
while ((l = r.readLine()) != null) {
if (l.startsWith("#")) {
continue;
}
return JsonProvider.class.cast(tccl.loadClass(l).newInstance());
}
} catch (final IOException x) {
// no-op
} finally {
try {
if (r != null) {
r.close();
}
} catch (final IOException y) {
// no-op
}
try {
if (in != null) {
in.close();
}
} catch (final IOException y) {
// no-op
}
}
}
} catch (final Exception ex) {
// no-op
}
try {
final Class<?> clazz = tccl.loadClass(DEFAULT_PROVIDER);
return JsonProvider.class.cast(clazz.newInstance());
} catch (final Throwable cnfe) {
throw new JsonException(DEFAULT_PROVIDER + " not found", cnfe);
}
}
public abstract JsonParser createParser(Reader reader);
public abstract JsonParser createParser(InputStream in);
public abstract JsonParserFactory createParserFactory(Map<String, ?> config);
public abstract JsonGenerator createGenerator(Writer writer);
public abstract JsonGenerator createGenerator(OutputStream out);
public abstract JsonGeneratorFactory createGeneratorFactory(Map<String, ?> config);
public abstract JsonReader createReader(Reader reader);
public abstract JsonReader createReader(InputStream in);
public abstract JsonWriter createWriter(Writer writer);
public abstract JsonWriter createWriter(OutputStream out);
public abstract JsonWriterFactory createWriterFactory(Map<String, ?> config);
public abstract JsonReaderFactory createReaderFactory(Map<String, ?> config);
public abstract JsonObjectBuilder createObjectBuilder();
public abstract JsonArrayBuilder createArrayBuilder();
public abstract JsonBuilderFactory createBuilderFactory(Map<String, ?> config);
}