Java tutorial
// Copyright (C) 2017 The Android Open Source Project // // 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 com.googlesource.gerrit.plugins.lfs.locks; import static com.google.gerrit.extensions.api.lfs.LfsDefinitions.CONTENTTYPE_VND_GIT_LFS_JSON; import static java.nio.charset.StandardCharsets.UTF_8; import static org.apache.http.HttpStatus.SC_OK; import com.google.common.base.Supplier; import com.google.common.base.Suppliers; import com.google.common.flogger.FluentLogger; import com.googlesource.gerrit.plugins.lfs.LfsGson; import java.io.BufferedReader; import java.io.BufferedWriter; import java.io.IOException; import java.io.InputStreamReader; import java.io.OutputStreamWriter; import java.io.Reader; import java.io.Writer; import javax.servlet.http.HttpServletRequest; import javax.servlet.http.HttpServletResponse; class LfsLocksContext { private static final FluentLogger log = FluentLogger.forEnclosingClass(); public final String path; private final HttpServletRequest req; private final HttpServletResponse res; private final Supplier<Writer> writer; private final Supplier<Reader> reader; private final LfsGson gson; LfsLocksContext(LfsGson gson, final HttpServletRequest req, final HttpServletResponse res) { this.path = req.getPathInfo().startsWith("/") ? req.getPathInfo() : "/" + req.getPathInfo(); this.req = req; this.res = res; this.writer = Suppliers.memoize(new Supplier<Writer>() { @Override public Writer get() { try { return new BufferedWriter(new OutputStreamWriter(res.getOutputStream(), UTF_8)); } catch (IOException e) { throw new RuntimeException(e); } } }); this.reader = Suppliers.memoize(new Supplier<Reader>() { @Override public Reader get() { try { return new BufferedReader(new InputStreamReader(req.getInputStream(), UTF_8)); } catch (IOException e) { throw new RuntimeException(e); } } }); this.gson = gson; setLfsResponseType(); } String getHeader(String name) { return req.getHeader(name); } String getParam(String name) { return req.getParameter(name); } <T> T input(Class<T> clazz) { return gson.fromJson(getReader(), clazz); } <T> void sendResponse(T content) throws IOException { res.setStatus(SC_OK); gson.toJson(content, getWriter()); getWriter().flush(); } void sendError(int status, String message) throws IOException { sendError(status, new Error(message)); } void sendError(int status, Error error) throws IOException { log.atSevere().log(error.message); res.setStatus(status); gson.toJson(error, getWriter()); getWriter().flush(); } Writer getWriter() { return writer.get(); } Reader getReader() { return reader.get(); } void setLfsResponseType() { res.setContentType(CONTENTTYPE_VND_GIT_LFS_JSON); } /** copied from org.eclipse.jgit.lfs.server.LfsProtocolServlet.Error */ static class Error { String message; Error(String m) { this.message = m; } } }