| /** |
| * Licensed to the Apache Software Foundation (ASF) under one |
| * or more contributor license agreements. See the NOTICE file |
| * distributed with this work for additional information |
| * regarding copyright ownership. The ASF licenses this file |
| * to you 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.apache.hadoop.util; |
| |
| import java.io.*; |
| import java.util.Calendar; |
| |
| import javax.servlet.*; |
| |
| public class ServletUtil { |
| /** |
| * Initial HTML header |
| */ |
| public static PrintWriter initHTML(ServletResponse response, String title |
| ) throws IOException { |
| response.setContentType("text/html"); |
| PrintWriter out = response.getWriter(); |
| out.println("<html>\n" |
| + "<link rel='stylesheet' type='text/css' href='/static/hadoop.css'>\n" |
| + "<title>" + title + "</title>\n" |
| + "<body>\n" |
| + "<h1>" + title + "</h1>\n"); |
| return out; |
| } |
| |
| /** |
| * Get a parameter from a ServletRequest. |
| * Return null if the parameter contains only white spaces. |
| */ |
| public static String getParameter(ServletRequest request, String name) { |
| String s = request.getParameter(name); |
| if (s == null) { |
| return null; |
| } |
| s = s.trim(); |
| return s.length() == 0? null: s; |
| } |
| |
| public static final String HTML_TAIL = "<hr />\n" |
| + "This is <a href='http://hadoop.apache.org/'>Apache Hadoop</a> release " |
| + VersionInfo.getVersion() + "\n" |
| + "</body></html>"; |
| |
| /** |
| * HTML footer to be added in the jsps. |
| * @return the HTML footer. |
| */ |
| public static String htmlFooter() { |
| return HTML_TAIL; |
| } |
| |
| /** |
| * Generate the percentage graph and returns HTML representation string |
| * of the same. |
| * |
| * @param perc The percentage value for which graph is to be generated |
| * @param width The width of the display table |
| * @return HTML String representation of the percentage graph |
| * @throws IOException |
| */ |
| public static String percentageGraph(int perc, int width) throws IOException { |
| assert perc >= 0; assert perc <= 100; |
| |
| StringBuilder builder = new StringBuilder(); |
| |
| builder.append("<table border=\"1px\" width=\""); builder.append(width); |
| builder.append("px\"><tr>"); |
| if(perc > 0) { |
| builder.append("<td cellspacing=\"0\" class=\"perc_filled\" width=\""); |
| builder.append(perc); builder.append("%\"></td>"); |
| }if(perc < 100) { |
| builder.append("<td cellspacing=\"0\" class=\"perc_nonfilled\" width=\""); |
| builder.append(100 - perc); builder.append("%\"></td>"); |
| } |
| builder.append("</tr></table>"); |
| return builder.toString(); |
| } |
| |
| /** |
| * Generate the percentage graph and returns HTML representation string |
| * of the same. |
| * @param perc The percentage value for which graph is to be generated |
| * @param width The width of the display table |
| * @return HTML String representation of the percentage graph |
| * @throws IOException |
| */ |
| public static String percentageGraph(float perc, int width) throws IOException { |
| return percentageGraph((int)perc, width); |
| } |
| } |
