/*
* Copyright 2015-2016 Red Hat, Inc. and/or its affiliates
* and other contributors as indicated by the @author tags.
*
* Licensed 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.hawkular.alerts.rest.json;
import java.io.IOException;
import java.util.regex.Matcher;
import java.util.regex.Pattern;
import com.fasterxml.jackson.core.JsonParseException;
import com.fasterxml.jackson.core.JsonParser;
import com.fasterxml.jackson.core.JsonProcessingException;
import com.fasterxml.jackson.databind.DeserializationContext;
import com.fasterxml.jackson.databind.JsonDeserializer;
/**
* Deserialize incoming json Links into Link objects
* Our input is like this:
*
* <pre>
* {
* "operationDefinitions": {
* "href": "http://localhost:7080/rest/operation/definitions?resourceId=10584"
* }
* }
* </pre>
*
* @author Heiko W. Rupp
* @see LinkSerializer
* @since 0.0.1
*/
public class LinkDeserializer extends JsonDeserializer<Link> {
Pattern textPattern = Pattern.compile("\\S+"); // Non whitespace; could possibly be narrowed
@Override
public Link deserialize(JsonParser jp, DeserializationContext ctxt) throws IOException {
String tmp = jp.getText(); // {
validate(jp, tmp, "{");
jp.nextToken(); // skip over { to the rel
String rel = jp.getText();
validateText(jp, rel);
jp.nextToken(); // skip over {
tmp = jp.getText();
validate(jp, tmp, "{");
jp.nextToken(); // skip over "href"
tmp = jp.getText();
validate(jp, tmp, "href");
jp.nextToken(); // skip to "http:// ... "
String href = jp.getText();
validateText(jp, href);
jp.nextToken(); // skip }
tmp = jp.getText();
validate(jp, tmp, "}");
jp.nextToken(); // skip }
tmp = jp.getText();
validate(jp, tmp, "}");
Link link = new Link(rel, href);
return link;
}
private void validateText(JsonParser jsonParser, String input) throws JsonProcessingException {
Matcher m = textPattern.matcher(input);
if (!m.matches()) {
throw new JsonParseException("Unexpected token: " + input, jsonParser.getTokenLocation());
}
}
private void validate(JsonParser jsonParser, String input, String expected) throws JsonProcessingException {
if (!input.equals(expected)) {
throw new JsonParseException("Unexpected token: " + input, jsonParser.getTokenLocation());
}
}
}