jetbrick.web.mvc.results.GSONResultHandler Maven / Gradle / Ivy
/**
* Copyright 2013-2014 Guoqiang Chen, Shanghai, China. All rights reserved.
*
* Email: [email protected]
* URL: http://subchen.github.io/
*
* 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 jetbrick.web.mvc.results;
import java.io.IOException;
import java.io.PrintWriter;
import java.util.Enumeration;
import java.util.Map;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import jetbrick.ioc.annotations.*;
import jetbrick.web.mvc.RequestContext;
import com.google.gson.*;
@Managed(JsonElement.class)
public class GSONResultHandler implements ResultHandler {
@Inject(required = false)
private Gson gson;
@IocInit
public void initialize() {
if (gson == null) {
gson = new Gson();
}
}
@Override
public void handle(RequestContext ctx, JsonElement result) throws IOException {
HttpServletRequest request = ctx.getRequest();
HttpServletResponse response = ctx.getResponse();
if (result == null) {
JsonObject json = new JsonObject();
Enumeration e = request.getAttributeNames();
while (e.hasMoreElements()) {
String name = e.nextElement();
Object value = request.getAttribute(name);
json.add(name, gson.toJsonTree(value));
}
for (Map.Entry entry : ctx.getModel().entrySet()) {
String key = entry.getKey();
Object value = entry.getValue();
json.add(key, gson.toJsonTree(value));
}
result = json;
}
String characterEncoding = request.getCharacterEncoding();
response.setCharacterEncoding(characterEncoding);
if (isOldIeBrowser(request)) {
response.setContentType("text/html;charset=" + characterEncoding);
} else {
response.setContentType("application/json;charset=" + characterEncoding);
}
PrintWriter out = response.getWriter();
out.write(result.toString());
out.flush();
}
// IE 10 以下的版本不支持 application/json
private boolean isOldIeBrowser(HttpServletRequest request) {
try {
String agent = request.getHeader("user-agent");
int ipos = agent.indexOf("MSIE");
if (ipos > 0) {
ipos = ipos + 4;
int jpos = agent.indexOf(';', ipos);
String version = agent.substring(ipos, jpos);
return Float.parseFloat(version) < 10;
}
} catch (Throwable e) {
return false;
}
return false;
}
}