org.apache.hadoop.util.ServletUtil Maven / Gradle / Ivy
/**
* 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 org.apache.hadoop.shaded.com.liance
* with the License. You may obtain a copy of the License at
*
* http://www.apache.org.apache.hadoop.shaded.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.shaded.org.apache.hadoop.util;
import java.org.apache.hadoop.shaded.io.*;
import java.util.Calendar;
import org.apache.hadoop.shaded.javax.servlet.*;
import org.apache.hadoop.shaded.javax.servlet.http.HttpServletRequest;
import org.apache.hadoop.shaded.org.apache.hadoop.classification.InterfaceAudience;
import org.apache.hadoop.shaded.org.apache.hadoop.classification.InterfaceStability;
import org.apache.hadoop.shaded.com.google.org.apache.hadoop.shaded.com.on.base.Preconditions;
@InterfaceAudience.Private
@InterfaceStability.Unstable
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("\n"
+ "\n"
+ "" + title + " \n"
+ "\n"
+ "" + title + "
\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;
}
/**
* @return a long value as passed in the given parameter, throwing
* an exception if it is not present or if it is not a valid number.
*/
public static long parseLongParam(ServletRequest request, String param)
throws IOException {
String paramStr = request.getParameter(param);
if (paramStr == null) {
throw new IOException("Invalid request has no " + param + " parameter");
}
return Long.parseLong(paramStr);
}
public static final String HTML_TAIL = "
\n"
+ "