/**
* Licensed to The Apereo Foundation under one or more contributor license
* agreements. See the NOTICE file distributed with this work for additional
* information regarding copyright ownership.
*
*
* The Apereo Foundation licenses this file to you under the Educational
* Community 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://opensource.org/licenses/ecl2.txt
*
* 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.opencastproject.util;
import static java.lang.String.format;
import static org.opencastproject.util.data.Option.none;
import static org.opencastproject.util.data.Option.some;
import static org.opencastproject.util.data.functions.Misc.cast;
import static org.opencastproject.util.data.functions.Misc.chuck;
import org.opencastproject.util.data.Function;
import org.opencastproject.util.data.Option;
import org.apache.commons.io.IOUtils;
import org.json.simple.parser.JSONParser;
import org.json.simple.parser.ParseException;
import java.io.IOException;
import java.io.InputStream;
import java.util.List;
import java.util.Map;
import java.util.Set;
/** Accessor for JSON objects aka maps. */
// todo -- think about using specialized Exception (JsonExcpetion ?); handle parse exception in jsonObj(String)
public final class JsonObj {
private final Map json;
/** Create a wrapper for a map. */
public JsonObj(Map json) {
this.json = json;
}
/** Constructor function. */
public static JsonObj jsonObj(Map json) {
return new JsonObj(json);
}
/** Create a JsonObj from a JSON string. */
public static JsonObj jsonObj(String json) {
return new JsonObj(parse(json));
}
public static JsonObj mk(InputStream in) throws IOException {
return new JsonObj(parse(IOUtils.toString(in)));
}
public static final Function<InputStream, JsonObj> fromInputStream = new Function.X<InputStream, JsonObj>() {
@Override
public JsonObj xapply(InputStream in) throws Exception {
return mk(in);
}
};
/** {@link #jsonObj(java.util.Map)} as a function. */
public static final Function<Map, JsonObj> jsonObj = new Function<Map, JsonObj>() {
@Override
public JsonObj apply(Map json) {
return jsonObj(json);
}
};
private static Map parse(String json) {
try {
return (Map) new JSONParser().parse(json);
} catch (ParseException e) {
return chuck(e);
}
}
public Set keySet() {
return json.keySet();
}
public JsonVal val(String key) {
return new JsonVal(get(Object.class, key));
}
public JsonVal valOpt(String key) {
return new JsonVal(get(Object.class, key));
}
public JsonObj obj(String key) {
return jsonObj(get(Map.class, key));
}
public JsonArr arr(String key) {
return new JsonArr(get(List.class, key));
}
public boolean has(String key) {
return json.containsKey(key);
}
/**
* Get mandatory value of type <code>ev</code>.
*
* @return the requested value if it exists and has the required type
* @deprecated
*/
public <A> A get(Class<A> ev, String key) {
final Object v = json.get(key);
if (v != null) {
try {
return cast(v, ev);
} catch (ClassCastException e) {
throw new RuntimeException(format("Key %s has not required type %s but %s", key, ev.getName(), v.getClass()
.getName()));
}
} else {
throw new RuntimeException(format("Key %s does not exist", key));
}
}
/**
* Get optional value of type <code>ev</code>.
*
* @return some if the value exists and has the required type, none otherwise
* @deprecated
*/
public <A> Option<A> opt(Class<A> ev, String key) {
final Object v = json.get(key);
if (v != null) {
try {
return some(cast(v, ev));
} catch (ClassCastException e) {
return none();
}
} else {
return none();
}
}
/**
* Get mandatory JSON object.
*
* @deprecated
*/
public JsonObj getObj(String key) {
return jsonObj(get(Map.class, key));
}
/**
* Get an optional JSON object.
*
* @deprecated
*/
public Option<JsonObj> optObj(String key) {
return opt(Map.class, key).map(jsonObj);
}
}