Admin: 1 версия

2010-06-01T06:11:06Z

1 версия

в 18:01, 31 мая 2010

2010-05-31T18:01:43Z

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== Another logger servlet ==



<source lang="java">

//Log4j from Apache is required
import org.apache.log4j.Logger;
import org.apache.log4j.PropertyConfigurator;
import javax.servlet.*;
import javax.servlet.http.*;
public class LoggerServlet2 extends HttpServlet {
private Logger log = null;
public void init() {
log = Logger.getLogger(LoggerServlet2.class);
}
public void doGet(HttpServletRequest request, HttpServletResponse response)
throws ServletException, java.io.IOException {
//display a DEBUG level message
log.debug("Sending a DEBUG message from logger2");
//display an INFO level message
log.info("Sending an INFO message from logger2");
//better display something
response.setContentType("text/html");
java.io.PrintWriter out = response.getWriter();
out.println("<html><head><title>Servlet logging</title></head><body>");
out.println("<h2>Hello from LoggerServlet</h2>");
out.println("Your logger name is: " + log.getName() + "<br>");
out.println("Your logger parent is: " + log.getParent().getName()
+ "<br>");
out.println("</body></html>");
out.close();
} //end doGet
public void doPost(HttpServletRequest request, HttpServletResponse response)
throws ServletException, java.io.IOException {
doGet(request, response);
}
}

</source>



== Context log ==



<source lang="java">

import javax.servlet.ServletContext;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
public class ContextLog extends HttpServlet {
public void doGet(HttpServletRequest request, HttpServletResponse response)
throws ServletException, java.io.IOException {
String yourMessage = request.getParameter("mine");
//Call the two ServletContext.log methods
//the javax.servlet.GenericServlet.getServletContext method
ServletContext context = getServletContext();
if (yourMessage == null || yourMessage.equals(""))
//log version with Throwable parameter
context.log("No message received:", new IllegalStateException(
"Missing parameter"));
else
context.log("Here is the visitor"s message: " + yourMessage);
response.setContentType("text/html");
java.io.PrintWriter out = response.getWriter();
//logging servlets probably want to display more HTML; this is "lazy
// HTML"
out.println("<html><head><title>ServletContext logging</title></head><body>");
out.println("<h2>Messages sent</h2>");
out.println("</body></html>");
} //end doGet
}

</source>



== Context logger ==



<source lang="java">

//Log4j from Apache is required
import org.apache.log4j.Logger;
import org.apache.log4j.PropertyConfigurator;
import javax.servlet.*;
import javax.servlet.http.*;
public class ContextLogger implements ServletContextListener {
private Logger log;
public ContextLogger() {
}
public void contextDestroyed(ServletContextEvent sce) {
String name = sce.getServletContext().getServletContextName();
//log request of the INFO level
log.info("ServletContext shut down: " + (name == null ? "" : name));
}
public void contextInitialized(ServletContextEvent sce) {
ServletContext context = sce.getServletContext();
String realPath = context.getRealPath("/");
String fileSep = System.getProperty("file.separator");
if (realPath != null && (!realPath.endsWith(fileSep)))
realPath = realPath + fileSep;
//Initialize logger here:
PropertyConfigurator.configure(realPath + "WEB-INF/classes/"
+ context.getInitParameter("logger-config"));
log = Logger.getLogger(ContextLogger.class);
String name = context.getServletContextName();
//log request about servlet context being initialized
log.info("ServletContext ready: " + (name == null ? "" : name));
}
}

</source>



== Log Filter ==



<source lang="java">

//Log4j from Apache is required
import javax.servlet.*;
import javax.servlet.http.*;
import org.apache.log4j.Logger;
import org.apache.log4j.PropertyConfigurator;
public class LogFilter implements Filter {
private FilterConfig config;
private Logger log;
/** Creates new RequestFilter */
public LogFilter() {
}
public void init(FilterConfig filterConfig) throws ServletException {
this.config = filterConfig;
//load the configuration for this application"s loggers using the
// servletLog.properties file
PropertyConfigurator.configure(config.getServletContext().getRealPath(
"/")
+ "WEB-INF/classes/servletLog.properties");
log = Logger.getLogger(LogFilter.class);
log.info("Logger instantiated in " + getClass().getName());
}
public void doFilter(ServletRequest request, ServletResponse response,
FilterChain chain) throws java.io.IOException, ServletException {
HttpServletRequest req = null;
String id = config.getInitParameter("log-id");
if (id == null)
id = "unknown";
if (log != null && (request instanceof HttpServletRequest)) {
req = (HttpServletRequest) request;
log.info("Log id:" + id + ": Request received from: "
+ req.getRemoteHost() + " for " + req.getRequestURL());
}
chain.doFilter(request, response);
}// doFilter
public void destroy() {
/*
* called before the Filter instance is removed from service by the web
* container
*/
log = null;
}
}

</source>



== Logger new config ==



<source lang="java">

//Log4j from Apache is required
import org.apache.log4j.Logger;
import javax.servlet.*;
import javax.servlet.http.*;
public class LoggerNewConfig extends HttpServlet {
private Logger log = null;
public void init() {
log = Logger.getLogger(LoggerNewConfig.class);
log.info("LoggerNewConfig started.");
}
public void doGet(HttpServletRequest request, HttpServletResponse response)
throws ServletException, java.io.IOException {
//display a DEBUG level message
log.debug("Sending a DEBUG message");
// display an INFO level message
log.info("Sending an INFO message");
//better display some HTML
response.setContentType("text/html");
java.io.PrintWriter out = response.getWriter();
out.println("<html><head><title>Servlet logging</title></head><body>");
out.println
("<h2>Hello from a Logger with its own configuration in the log4j.properties file</h2>");
out.println("Your logger name is: " + log.getName() + "<br>");
out.println("Your logger parent is: " + log.getParent().getName()
+ "<br>");
out.println("</body></html>");
out.close();
} //end doGet
public void doPost(HttpServletRequest request, HttpServletResponse response)
throws ServletException, java.io.IOException {
doGet(request, response);
}
}

</source>



== Logger Servlet ==



<source lang="java">

//Log4j from Apache is required
import org.apache.log4j.Logger;
import org.apache.log4j.PropertyConfigurator;
import javax.servlet.*;
import javax.servlet.http.*;
public class LoggerServlet extends HttpServlet {
private Logger log = null;
public void init() {
String realPath = getServletContext().getRealPath("/");
String fileSep = System.getProperty("file.separator");
if (realPath != null && (!realPath.endsWith(fileSep)))
realPath = realPath + fileSep;
System.out.println(realPath);
//load the configuration for this application"s loggers using the
// servletLog.properties file
PropertyConfigurator.configure(realPath
+ "WEB-INF/classes/servletLog.properties");
//create the logger for this servlet class
//it will use the configuration for the logger com.jexp.LoggerServlet
//or inherit from the logger com.jexp if one exists, and so on
log = Logger.getLogger(LoggerServlet.class);
log.info("LoggerServlet started.");
}
public void doGet(HttpServletRequest request, HttpServletResponse response)
throws ServletException, java.io.IOException {
//display a DEBUG level message
log.debug("Sending a DEBUG message");
//display an INFO level message
log.info("Sending an INFO message");
//better display something
response.setContentType("text/html");
java.io.PrintWriter out = response.getWriter();
out.println("<html><head><title>Servlet logging</title></head><body>");
out.println("<h2>Hello from LoggerServlet</h2>");
out.println("Your logger name is: " + log.getName() + "<br>");
out.println("Your logger parent is: " + log.getParent().getName()
+ "<br>");
out.println("</body></html>");
out.close();
} //end doGet
public void doPost(HttpServletRequest request, HttpServletResponse response)
throws ServletException, java.io.IOException {
doGet(request, response);
}
}

</source>



== LoggerSkel for Servlet ==



<source lang="java">

//Log4j from Apache is required

import org.apache.log4j.Logger;
import org.apache.log4j.PropertyConfigurator;
import javax.servlet.*;
import javax.servlet.http.*;
public class LoggerSkel extends HttpServlet {
private Logger log;
public void init() {
PropertyConfigurator.configure(getServletContext().getRealPath("/")
+ "WEB-INF/classes/servletLog.properties");
log = Logger.getLogger(LoggerSkel.class);
log.debug("Instance created of: " + getClass().getName());
}
public void doGet(HttpServletRequest request, HttpServletResponse response)
throws ServletException, java.io.IOException {
//do logging here if necessary
} //end doGet
}

</source>



== Logger without configure file ==



<source lang="java">

//Log4j from Apache is required
import org.apache.log4j.Logger;
import org.apache.log4j.BasicConfigurator;
import javax.servlet.*;
import javax.servlet.http.*;
public class LoggerNconfig extends HttpServlet {
private Logger log = null;
public void init() {
log = Logger.getRootLogger();
BasicConfigurator.configure();
}
public void doGet(HttpServletRequest request, HttpServletResponse response)
throws ServletException, java.io.IOException {
//display a DEBUG level message
log.debug("Sending a DEBUG message");
// display an INFO level message
log.info("Sending an INFO message");
//better display some HTML
response.setContentType("text/html");
java.io.PrintWriter out = response.getWriter();
out.println("<html><head><title>Servlet logging</title></head><body>");
out.println("<h2>Hello from a Logger with no Config file</h2>");
out.println("Your logger name is: " + log.getName() + "<br>");
out.println("Your logger parent is: " + log.getParent().getName()
+ "<br>");
out.println("</body></html>");
} //end doGet
public void doPost(HttpServletRequest request, HttpServletResponse response)
throws ServletException, java.io.IOException {
doGet(request, response);
}
}

</source>



== Logging Filter ==



<source lang="java">

import java.io.*;
import javax.servlet.*;
import javax.servlet.http.*;
public final class LoggingFilter implements Filter
{
private FilterConfig filterConfig = null;
public void doFilter(ServletRequest request, ServletResponse response,
FilterChain chain)
throws IOException, ServletException
{
long start = System.currentTimeMillis();
String address = request.getRemoteAddr();
String file = ((HttpServletRequest) request).getRequestURI();

chain.doFilter(request, response);
filterConfig.getServletContext().log(
"User access! " +
" User IP: " + address +
" Resource: " + file +
" Milliseconds used: " + (System.currentTimeMillis() - start)
);
}
public void destroy() { }
public void init(FilterConfig filterConfig) {
this.filterConfig = filterConfig;
}
}

</source>



== Log in ServletContext ==



<source lang="java">

// web.xml
/*
<?xml version="1.0" encoding="ISO-8859-1"?>
<web-app xmlns="http://java.sun.ru/xml/ns/j2ee"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://java.sun.ru/xml/ns/j2ee
http://java.sun.ru/xml/ns/j2ee/web-app_2_4.xsd" version="2.4">
<servlet>
<servlet-name>LoggingServlet</servlet-name>
<servlet-class>LoggingServlet</servlet-class>
</servlet>
<servlet-mapping>
<servlet-name>LoggingServlet</servlet-name>
<url-pattern>/loggingServlet</url-pattern>
</servlet-mapping>
</web-app>
*/
import java.io.IOException;
import javax.servlet.ServletConfig;
import javax.servlet.ServletContext;
import javax.servlet.ServletException;
import javax.servlet.ServletOutputStream;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
public class LoggingServlet extends HttpServlet {
private ServletContext context;
public void init(ServletConfig config) throws ServletException {
super.init(config);
context = getServletContext();
context.log("Init has been invoked");
}
public void doGet(HttpServletRequest req, HttpServletResponse res)
throws IOException {
ServletOutputStream out = res.getOutputStream();
context.log("doGet has now been invoked");
res.setContentType("text/html");
out.println("<html><head><title>Logging Servlet</title></head>");
out.println("<body>Visit the <tomcat-home>\\logs and open the xx file to see the log entries");
out.println("</body></html>");
}
}

</source>



== Servlet Logging ==



<source lang="java">

package net.firstpartners.nounit.utility;
/**
* Title: NoUnit - Identify Classes that are not being unit Tested
*
* Copyright (C) 2001 Paul Browne , FirstPartners.net
*
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version 2
* of the License, or (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
*
* @author Paul Browne
* @version 0.6
*/
import java.io.*;
import javax.servlet.*;

/**
* stores log of system output and system errors
* If Servlet , writes to Servlet Log File.
* If non-Servlet , writes to Output Files Specified in parameters.<BR>
* Class is mainly static , to allow ease of use (one one log file per system!!) ,
* but has a non-static constructor (for use by servlets - so reference to servlet
* log file can be set.
*/
public class Logging {
//Class Level Variables
static String logFileName; // both package level to enable testing
static String errorLogFileName;
static FileWriter logWriter;
static FileWriter errorWriter;
static boolean doLogging=false; //default no logging unless file says otherwise
//For use in Servlet Context Logging
static ServletContext innerContext;

/**
* Constructor for Logging from Servlet
* @param inServletContext used to get access to the Servlet log files
* @exception IOException if it can"t create log files
*/
public Logging (ServletContext inServletContext) throws IOException {
//Store incoming Context + Set Logging Flag
this.innerContext= inServletContext;
//Set logging flag
doLogging=true;

}

/**
* do Setup
* @exception IOException if it can"t create log files
*/
private static void setup () {
try {
//Check if setup required - ie nothing has been setup before
if (((logFileName==null)&&(errorLogFileName==null))||(innerContext==null))
{
//Set logging flag

doLogging=true;
//Get logging parameters
logFileName= "LogFile.txt";
errorLogFileName = "ErrorLogFile.txt";
//Create the files
logWriter = new FileWriter(logFileName,true); //append data
errorWriter = new FileWriter(errorLogFileName,true); //append

}
} catch (java.io.IOException ie) {
//do nothing - exists to keep method signature simple
//will show up as NullPointerException later
}
}
/**
* Print log of system output
* @param sysOut
*/
public static void printOutput(Object sysOut){
//setup (if required)
setup();
//skip out asap if logging is turned off
if (!doLogging) {return; }

//Check for Servlet Logging
if (innerContext!=null) {
doServletLog(sysOut);
} else {
//do file logging
try {
if (sysOut instanceof Exception) {
logWriter.write(((Exception)sysOut).toString());
logWriter.flush();
}
else {
logWriter.write(sysOut.toString());
logWriter.flush();
}
} catch (java.io.IOException ioe) {
//do nothing - let app continue
}
}
}
/**
* Print log of system errors
* This method catches java.io.IOExceptions internally , so as to give a
* similar method signature to System.out.println. Also should we stop system
* if logging (and only logging) fails?
* @param sysErr
*/
public static void printError(Object sysErr){
//setup (if required)
setup();
//skip out asap if logging is turned off
if (!doLogging) {return; }
//Check for Servlet Logging
if (innerContext!=null) {
doServletLog(sysErr);
} else {
//do file logging
try {
if (sysErr instanceof Exception) {
logWriter.write(((Exception)sysErr).toString());
logWriter.flush();
}
else {
logWriter.write(sysErr.toString());
logWriter.flush();
}
} catch (java.io.IOException ioe) {
//do nothing - let app continue
}
}
}
/**
* private method for handling logging to Servlets
* @param inObject to Log
*/
private static void doServletLog (Object inObject) {
if(inObject instanceof Throwable) {
//Log as Exception
innerContext.log("",(Throwable)inObject);
} else {
//Log as Normal String
innerContext.log(inObject.toString());
}

}

/**
* Prints debug message to system log file.
* Catches java.io.IOExceptions internally, so as to give a
* similar method signature to System.out.println.
*
* @param object Object containing information to display
*/
public static void debug(Object object){
setup();
if (doLogging) {
if (innerContext==null) {
// log debug message to file
try {
try {
logWriter.write(((Exception)object).toString());
}
catch (ClassCastException e) {
logWriter.write(object.toString());
}
logWriter.flush();
} catch (IOException e) {
//do nothing - let app continue
}
} else {
doServletLog(object);
}
}
}

}

</source>



== Servlet: Root logger ==



<source lang="java">

//Log4j from Apache is required
import org.apache.log4j.Logger;
import javax.servlet.*;
import javax.servlet.http.*;
public class LoggerWconfig extends HttpServlet {
private Logger log = null;
public void init() {
log = Logger.getRootLogger();
log.info("LoggerWconfig started.");
}
public void doGet(HttpServletRequest request, HttpServletResponse response)
throws ServletException, java.io.IOException {
//display a DEBUG level message
log.debug("Sending a DEBUG message");
// display an INFO level message
log.info("Sending an INFO message");
//better display some HTML
response.setContentType("text/html");
java.io.PrintWriter out = response.getWriter();
out.println("<html><head><title>Servlet logging</title></head><body>");
out.println("<h2>Hello from a Logger with a log4j.properties file</h2>");
out.println("Your logger name is: " + log.getName() + "<br>");
out.println("</body></html>");
}
public void doPost(HttpServletRequest request, HttpServletResponse response)
throws ServletException, java.io.IOException {
doGet(request, response);
}
}

</source>



== Servlets Logging Filter Demo ==

← Предыдущая	Версия 06:11, 1 июня 2010
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Java/Servlets/Log - История изменений

Admin: 1 версия

в 18:01, 31 мая 2010