Java tutorial
/** * Copyright 2014 Netflix, Inc. * * 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.netflix.raigad.utils; import com.google.common.base.Charsets; import com.google.common.hash.HashCode; import com.google.common.hash.Hashing; import com.google.common.io.Files; import org.apache.commons.codec.binary.Base64; import org.apache.commons.io.FileUtils; import org.apache.commons.io.IOUtils; import org.apache.commons.lang.StringUtils; import org.apache.http.HttpResponse; import org.apache.http.client.methods.HttpGet; import org.apache.http.client.methods.HttpPost; import org.apache.http.client.methods.HttpPut; import org.apache.http.entity.StringEntity; import org.apache.http.impl.client.DefaultHttpClient; import org.apache.http.params.BasicHttpParams; import org.apache.http.params.HttpConnectionParams; import org.apache.http.params.HttpParams; import org.joda.time.DateTime; import org.joda.time.format.DateTimeFormat; import org.joda.time.format.DateTimeFormatter; import org.slf4j.Logger; import org.slf4j.LoggerFactory; import java.io.*; import java.net.HttpURLConnection; import java.net.URL; import java.nio.charset.StandardCharsets; import java.security.MessageDigest; import java.util.List; public class SystemUtils { private static final Logger logger = LoggerFactory.getLogger(SystemUtils.class); public static String getDataFromUrl(String url) { try { HttpURLConnection conn = (HttpURLConnection) new URL(url).openConnection(); conn.setConnectTimeout(1000); conn.setReadTimeout(1000); conn.setRequestMethod("GET"); if (conn.getResponseCode() != 200) { throw new RuntimeException("Unable to get data for URL " + url); } byte[] b = new byte[2048]; ByteArrayOutputStream bos = new ByteArrayOutputStream(); DataInputStream d = new DataInputStream((FilterInputStream) conn.getContent()); int c = 0; while ((c = d.read(b, 0, b.length)) != -1) bos.write(b, 0, c); String return_ = new String(bos.toByteArray(), Charsets.UTF_8); logger.info("Calling URL API: {} returns: {}", url, return_); conn.disconnect(); return return_; } catch (Exception ex) { throw new RuntimeException(ex); } } public static String runHttpGetCommand(String url) throws Exception { String return_; DefaultHttpClient client = new DefaultHttpClient(); InputStream isStream = null; try { HttpParams httpParameters = new BasicHttpParams(); int timeoutConnection = 1000; int timeoutSocket = 1000; HttpConnectionParams.setConnectionTimeout(httpParameters, timeoutConnection); HttpConnectionParams.setSoTimeout(httpParameters, timeoutSocket); client.setParams(httpParameters); HttpGet getRequest = new HttpGet(url); getRequest.setHeader("Content-type", "application/json"); HttpResponse resp = client.execute(getRequest); if (resp == null || resp.getEntity() == null) { throw new ESHttpException("Unable to execute GET URL (" + url + ") Exception Message: < Null Response or Null HttpEntity >"); } isStream = resp.getEntity().getContent(); if (resp.getStatusLine().getStatusCode() != 200) { throw new ESHttpException("Unable to execute GET URL (" + url + ") Exception Message: (" + IOUtils.toString(isStream, StandardCharsets.UTF_8.toString()) + ")"); } return_ = IOUtils.toString(isStream, StandardCharsets.UTF_8.toString()); logger.debug("GET URL API: {} returns: {}", url, return_); } catch (Exception e) { throw new ESHttpException( "Caught an exception during execution of URL (" + url + ")Exception Message: (" + e + ")"); } finally { if (isStream != null) isStream.close(); } return return_; } public static String runHttpPutCommand(String url, String jsonBody) throws IOException { String return_; DefaultHttpClient client = new DefaultHttpClient(); InputStream isStream = null; try { HttpParams httpParameters = new BasicHttpParams(); int timeoutConnection = 1000; int timeoutSocket = 1000; HttpConnectionParams.setConnectionTimeout(httpParameters, timeoutConnection); HttpConnectionParams.setSoTimeout(httpParameters, timeoutSocket); client.setParams(httpParameters); HttpPut putRequest = new HttpPut(url); putRequest.setEntity(new StringEntity(jsonBody, StandardCharsets.UTF_8)); putRequest.setHeader("Content-type", "application/json"); HttpResponse resp = client.execute(putRequest); if (resp == null || resp.getEntity() == null) { throw new ESHttpException("Unable to execute PUT URL (" + url + ") Exception Message: < Null Response or Null HttpEntity >"); } isStream = resp.getEntity().getContent(); if (resp.getStatusLine().getStatusCode() != 200) { throw new ESHttpException("Unable to execute PUT URL (" + url + ") Exception Message: (" + IOUtils.toString(isStream, StandardCharsets.UTF_8.toString()) + ")"); } return_ = IOUtils.toString(isStream, StandardCharsets.UTF_8.toString()); logger.debug("PUT URL API: {} with JSONBody {} returns: {}", url, jsonBody, return_); } catch (Exception e) { throw new ESHttpException( "Caught an exception during execution of URL (" + url + ")Exception Message: (" + e + ")"); } finally { if (isStream != null) isStream.close(); } return return_; } public static String runHttpPostCommand(String url, String jsonBody) throws IOException { String return_; DefaultHttpClient client = new DefaultHttpClient(); InputStream isStream = null; try { HttpParams httpParameters = new BasicHttpParams(); int timeoutConnection = 1000; int timeoutSocket = 1000; HttpConnectionParams.setConnectionTimeout(httpParameters, timeoutConnection); HttpConnectionParams.setSoTimeout(httpParameters, timeoutSocket); client.setParams(httpParameters); HttpPost postRequest = new HttpPost(url); if (StringUtils.isNotEmpty(jsonBody)) postRequest.setEntity(new StringEntity(jsonBody, StandardCharsets.UTF_8)); postRequest.setHeader("Content-type", "application/json"); HttpResponse resp = client.execute(postRequest); if (resp == null || resp.getEntity() == null) { throw new ESHttpException("Unable to execute POST URL (" + url + ") Exception Message: < Null Response or Null HttpEntity >"); } isStream = resp.getEntity().getContent(); if (resp.getStatusLine().getStatusCode() != 200) { throw new ESHttpException("Unable to execute POST URL (" + url + ") Exception Message: (" + IOUtils.toString(isStream, StandardCharsets.UTF_8.toString()) + ")"); } return_ = IOUtils.toString(isStream, StandardCharsets.UTF_8.toString()); logger.debug("POST URL API: {} with JSONBody {} returns: {}", url, jsonBody, return_); } catch (Exception e) { throw new ESHttpException( "Caught an exception during execution of URL (" + url + ")Exception Message: (" + e + ")"); } finally { if (isStream != null) isStream.close(); } return return_; } /** * delete all the files/dirs in the given Directory but dont delete the dir * itself. */ public static void cleanupDir(String dirPath, List<String> childdirs) throws IOException { if (childdirs == null || childdirs.size() == 0) FileUtils.cleanDirectory(new File(dirPath)); else { for (String cdir : childdirs) FileUtils.cleanDirectory(new File(dirPath + "/" + cdir)); } } public static void createDirs(String location) { File dirFile = new File(location); if (dirFile.exists() && dirFile.isFile()) { dirFile.delete(); dirFile.mkdirs(); } else if (!dirFile.exists()) dirFile.mkdirs(); } public static byte[] md5(byte[] buf) { try { MessageDigest mdigest = MessageDigest.getInstance("MD5"); mdigest.update(buf, 0, buf.length); return mdigest.digest(); } catch (Exception e) { throw new RuntimeException(e); } } /** * Get a Md5 string which is similar to OS Md5sum */ public static String md5(File file) { try { HashCode hc = Files.hash(file, Hashing.md5()); return toHex(hc.asBytes()); } catch (Exception e) { throw new RuntimeException(e); } } public static String toHex(byte[] digest) { StringBuffer sb = new StringBuffer(digest.length * 2); for (int i = 0; i < digest.length; i++) { String hex = Integer.toHexString(digest[i]); if (hex.length() == 1) { sb.append("0"); } else if (hex.length() == 8) { hex = hex.substring(6); } sb.append(hex); } return sb.toString().toLowerCase(); } public static String toBase64(byte[] md5) { byte encoded[] = Base64.encodeBase64(md5, false); return new String(encoded); } public static String formatDate(DateTime dateTime, String dateFormat) { DateTimeFormatter fmt = DateTimeFormat.forPattern(dateFormat); return dateTime.toString(fmt); } }