File operations in Java Read file, write into file, Append file
File operations involved majorly are reading it , writing into a file and appending it.
Reading from a File :
try {
BufferedReader in = new BufferedReader(new FileReader("infilename"));
String str;
while ((str = in.readLine()) != null) {
process(str);
}
in.close();
} catch (IOException e) {
}
BufferedReader in = new BufferedReader(new FileReader("infilename"));
String str;
while ((str = in.readLine()) != null) {
process(str);
}
in.close();
} catch (IOException e) {
}
Writing into a File :
try {
BufferedWriter out = new BufferedWriter(new FileWriter("outfilename"));
out.write("aString");
out.close();
} catch (IOException e) {
}
Appending to a File :
try {
BufferedWriter out = new BufferedWriter(new FileWriter("filename", true));
out.write("aString");
out.close();
} catch (IOException e) {
}
Running batch scripts through java and wait for it to complete which internally calls java processes.
The below example show how can we wait for the script to complete running.
public static void main(String[] args) throws InterruptedException,
IOException {
System.out.println("Starting ");
Runtime runtime = Runtime.getRuntime();
String[] command = { "cmd.exe", "/C", "start /WAIT",
"C:\\Users\\IBM_ADMIN\\Desktop\\BVT31\\BVT31\\xFAST.bat",
"--cf", "IE_Configurations.properties", "--tc",
"scripts\\testCases" };
Process p = runtime
.exec(command, null, new File(tipBVTScriptsPath));
p.waitFor();
System.out.println(p.exitValue());
}
String[] command = { "cmd.exe", "/C", "start /WAIT",....
Start /WAIT is the main thing to be understood here which will wait for the launched batch script in the separate window to get completed.
Once all the actions in the batch are completed the window remains open.
Hence the main important point here is to have "exit" statement as the last statement in the batch script which runs as process.
The below example show how can we wait for the script to complete running.
public static void main(String[] args) throws InterruptedException,
IOException {
System.out.println("Starting ");
Runtime runtime = Runtime.getRuntime();
String[] command = { "cmd.exe", "/C", "start /WAIT",
"C:\\Users\\IBM_ADMIN\\Desktop\\BVT31\\BVT31\\xFAST.bat",
"--cf", "IE_Configurations.properties", "--tc",
"scripts\\testCases" };
Process p = runtime
.exec(command, null, new File(tipBVTScriptsPath));
p.waitFor();
System.out.println(p.exitValue());
}
Start /WAIT is the main thing to be understood here which will wait for the launched batch script in the separate window to get completed.
Once all the actions in the batch are completed the window remains open.
Hence the main important point here is to have "exit" statement as the last statement in the batch script which runs as process.
Running batch script using JAVA and storing output in a log file.
Batch script to be run will take input parameters / arguments.The below simple Java code will help to run a batch file (bat script) and store the output of batch run in to a file. The batch script to be run from the java takes few parameters as inputs.
import java.io.BufferedReader;
import java.io.BufferedWriter;
import java.io.File;
import java.io.FileWriter;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.net.InetAddress;
public class ApplicabilityCheck {
public static void main(String[] args) {
try {
System.out.println("ESS BVT");
String cfgprefix = "server1";
InetAddress hostname = InetAddress.getLocalHost();
String host = hostname.getCanonicalHostName();
String httpsPort = "16311";
String truststorepassword = "krishna";
String basicauthuser = "krishna";
String basicauthpassword = "krishna";
String essCleintPath = "C:\\Krish\\My Docs\\Foundation services install\\ESS - 15183\\ESSAuthnClientApp\\MyApp\\bin";
String essOutputDir = "C:\\Krish\\My Docs\\Foundation services install\\ESS - 15183\\ESSAuthnClientApp";
String passString = "succeeded";
File tokenOutFile = new File("ESS_Token_Out");
File essOutputFile = new File(essOutputDir + "\\ESS_OUTPUT.log");
File iosdpTrustStoreFile = new File(essCleintPath + "\\16311.jks");
File runExampleFile = new File(essCleintPath+ "\\runExampleApp.bat");
if (iosdpTrustStoreFile.exists() && runExampleFile.exists()) {
System.out.println("File:- "
+ iosdpTrustStoreFile.getAbsolutePath() + " Exists");
String setupExampleString = "setupExampleApp.bat -cfgprefix "
+ cfgprefix + " -host " + host + " -port " + httpsPort
+ " -protocol https -truststorelocation \""
+ iosdpTrustStoreFile.getAbsolutePath()
+ "\" -truststorepassword " + truststorepassword
+ " -basicauthuser " + basicauthuser
+ " -basicauthpassword " + basicauthpassword;
System.out.println(setupExampleString);
String runExampleAppString = "\""
+ runExampleFile.getAbsolutePath() + "\" " + cfgprefix
+ " -tokenOutFile " + tokenOutFile.getName() + " -uname "
+ basicauthuser + " -pword " + basicauthpassword;
System.out.println(runExampleAppString);
/* Now running the Run Example */
Runtime runtime = Runtime.getRuntime();
Process p = runtime.exec(runExampleAppString, null, new File(essCleintPath));
String line;
BufferedReader r = new BufferedReader(new InputStreamReader(p.getInputStream()));
BufferedWriter w = new BufferedWriter(new FileWriter(essOutputFile));
while ((line = r.readLine()) != null) {
if(line.contains(passString)) System.out.println("ESS installed");
w.write(line);
}
r.close();
w.close();
} else
System.out.println("Trust Store JKS file is not available");
} catch (Exception e) {
System.out.println(e);
}
}
}
References:
[1]
How to invoke p(j)ython script through ANT scripts do deploy WAR files on to Webshere. ?
1. The ant script will invoke python files.
2. Ant script's target pathconvert will convert the property values containg back slashes in a file path to forward slashes.
3. Ant script target timestamp will print the time stamp along with message in the given log file. Takes care of new line character using 
 at the end of message ...
Ant Script to call jython scripts which will deploy and undeploy provided J2E WAR file.
Below is the Ant script.
hi
<project name="DeployFSAdmin" default="install" basedir=".">
<description>
Silent Deployment of WAR files
</description>
<property name="FSAdminLog" value="c:/FSAdmin_install.log" />
<target id="install" name="install" depends="pathconvert">
<antcall target="timestamp">
<param name="LogFile" value="${FSAdminLog}" />
<param name="Message" value="Starting Server now" />
</antcall>
<exec executable="C:\\Program Files\\IBM\\WebSphere\\AppServer\\profiles\\AppSrv01\\bin\\startServer.bat" output="${FSAdminLog}" append="true">
<arg value="server1" />
</exec>
<antcall target="timestamp">
<param name="LogFile" value="${FSAdminLog}" />
<param name="Message" value="Starting FS Admin App Deployment now" />
</antcall>
<exec executable="C:\\Program Files\\IBM\\WebSphere\\AppServer\\profiles\\AppSrv01\\bin\\wsadmin.bat" output="${FSAdminLog}" append="true">
<arg value="-lang" />
<arg value="jython" />
<arg value="-username" />
<arg value="krishna" />
<arg value="-password" />
<arg value="krishna" />
<arg value="-f" />
<arg value="${deployFile}" />
<arg value="${updatedWARFile}" />
<arg value="FSAdminApp" />
<arg value="server1" />
</exec>
<antcall target="timestamp">
<param name="LogFile" value="${FSAdminLog}" />
<param name="Message" value="FS Admin App Deployment completed" />
</antcall>
</target>
<target id="unistall" name="uninstall">
<antcall target="timestamp">
<param name="LogFile" value="${FSAdminLog}" />
<param name="Message" value="Starting Server now." />
</antcall>
<exec executable="C:\\Program Files\\IBM\\WebSphere\\AppServer\\profiles\\AppSrv01\\bin\\startServer.bat" output="${FSAdminLog}" append="true">
<arg value="server1" />
</exec>
<antcall target="timestamp">
<param name="LogFile" value="${FSAdminLog}" />
<param name="Message" value="Un-Deployment of FS Admin in progress..." />
</antcall>
<exec executable="C:\\Program Files\\IBM\\WebSphere\\AppServer\\profiles\\AppSrv01\\bin\\wsadmin.bat" output="${FSAdminLog}" append="true">
<arg value="-lang" />
<arg value="jython" />
<arg value="-username" />
<arg value="krishna" />
<arg value="-password" />
<arg value="krishna" />
<arg value="-f" />
<arg value="${undeployFile}" />
<arg value="FSAdminApp" />
<arg value="server1" />
</exec>
<antcall target="timestamp">
<param name="LogFile" value="${FSAdminLog}" />
<param name="Message" value="Undeployment of FASApp completed" />
</antcall>
</target>
<!-- The target "pathconvert" is to convert all the windows back slahes into forward slashes-->
<target id="pathconvert" name="pathconvert">
<tempfile property="temp.file" />
<echo message="${warfile}" file="${temp.file}" />
<loadfile srcfile="${temp.file}" property="updatedWARFile">
<filterchain>
<replaceregex pattern="\\" replace="/" flags="g" />
</filterchain>
</loadfile>
<delete file="${temp.file}" />
</target>
<!-- To print the time stamp along with message in a log file -->
<target name="timestamp">
<tstamp>
<format property="logtime" pattern="yyyy.MM.dd ':' HH:mm:ss z" />
</tstamp>
<!-- New line charecter uasage 
 -->
<echo file="${LogFile}" message="
${logtime} : ${Message}.
" append="true" />
</target>
</project>
Below is the Deploying Python file.<project name="DeployFSAdmin" default="install" basedir=".">
<description>
Silent Deployment of WAR files
</description>
<property name="FSAdminLog" value="c:/FSAdmin_install.log" />
<target id="install" name="install" depends="pathconvert">
<antcall target="timestamp">
<param name="LogFile" value="${FSAdminLog}" />
<param name="Message" value="Starting Server now" />
</antcall>
<exec executable="C:\\Program Files\\IBM\\WebSphere\\AppServer\\profiles\\AppSrv01\\bin\\startServer.bat" output="${FSAdminLog}" append="true">
<arg value="server1" />
</exec>
<antcall target="timestamp">
<param name="LogFile" value="${FSAdminLog}" />
<param name="Message" value="Starting FS Admin App Deployment now" />
</antcall>
<exec executable="C:\\Program Files\\IBM\\WebSphere\\AppServer\\profiles\\AppSrv01\\bin\\wsadmin.bat" output="${FSAdminLog}" append="true">
<arg value="-lang" />
<arg value="jython" />
<arg value="-username" />
<arg value="krishna" />
<arg value="-password" />
<arg value="krishna" />
<arg value="-f" />
<arg value="${deployFile}" />
<arg value="${updatedWARFile}" />
<arg value="FSAdminApp" />
<arg value="server1" />
</exec>
<antcall target="timestamp">
<param name="LogFile" value="${FSAdminLog}" />
<param name="Message" value="FS Admin App Deployment completed" />
</antcall>
</target>
<target id="unistall" name="uninstall">
<antcall target="timestamp">
<param name="LogFile" value="${FSAdminLog}" />
<param name="Message" value="Starting Server now." />
</antcall>
<exec executable="C:\\Program Files\\IBM\\WebSphere\\AppServer\\profiles\\AppSrv01\\bin\\startServer.bat" output="${FSAdminLog}" append="true">
<arg value="server1" />
</exec>
<antcall target="timestamp">
<param name="LogFile" value="${FSAdminLog}" />
<param name="Message" value="Un-Deployment of FS Admin in progress..." />
</antcall>
<exec executable="C:\\Program Files\\IBM\\WebSphere\\AppServer\\profiles\\AppSrv01\\bin\\wsadmin.bat" output="${FSAdminLog}" append="true">
<arg value="-lang" />
<arg value="jython" />
<arg value="-username" />
<arg value="krishna" />
<arg value="-password" />
<arg value="krishna" />
<arg value="-f" />
<arg value="${undeployFile}" />
<arg value="FSAdminApp" />
<arg value="server1" />
</exec>
<antcall target="timestamp">
<param name="LogFile" value="${FSAdminLog}" />
<param name="Message" value="Undeployment of FASApp completed" />
</antcall>
</target>
<!-- The target "pathconvert" is to convert all the windows back slahes into forward slashes-->
<target id="pathconvert" name="pathconvert">
<tempfile property="temp.file" />
<echo message="${warfile}" file="${temp.file}" />
<loadfile srcfile="${temp.file}" property="updatedWARFile">
<filterchain>
<replaceregex pattern="\\" replace="/" flags="g" />
</filterchain>
</loadfile>
<delete file="${temp.file}" />
</target>
<!-- To print the time stamp along with message in a log file -->
<target name="timestamp">
<tstamp>
<format property="logtime" pattern="yyyy.MM.dd ':' HH:mm:ss z" />
</tstamp>
<!-- New line charecter uasage 
 -->
<echo file="${LogFile}" message="
${logtime} : ${Message}.
" append="true" />
</target>
</project>
hi
'''
Created on Jan 18, 2012
@author: krishna
'''
import sys
#--------------------------------------------------------------
# Install an application onto this server
#--------------------------------------------------------------
def install(serverName, nodeName, app, appName=None):
print "Installing the application"
appOptions = "[-server " + serverName + " -node " + nodeName
if len(appName) != 0:
appOptions = appOptions + " -appname " + appName +" -contextroot " + appName
appOptions = appOptions + " -defaultbinding.virtual.host default_host -usedefaultbindings]"
print "Server Options: " + appOptions
AdminApp.install(app, appOptions)
#--------------------------------------------------------------
# Save all changes and stop the server
#--------------------------------------------------------------
print "Now saving all the configurations"
AdminConfig.save()
print "Now stoping the server"
AdminControl.stopServer(serverName, nodeName)
#-----------------------------------------------------------------
# Main
#-----------------------------------------------------------------
if (len(sys.argv) != 3):
print "This script requires 3 parameters:, , "
print "e.g.: argsDeployWARfile.py C:/Krish/SimpleJ2E_1.0.0.war SimpleJ2E server1"
else:
application = sys.argv[0]
appName = sys.argv[1]
print "application: " + application
print "app name: " + appName
nodeName = AdminControl.getNode()
print nodeName
serverName = sys.argv[2]
print serverName
install(serverName, nodeName, application, appName)
Below is the un-deploying Python file.'''
Created on Jan 18, 2012
@author: krishna
'''
import sys
#--------------------------------------------------------------
# Install an application onto this server
#--------------------------------------------------------------
def install(serverName, nodeName, app, appName=None):
print "Installing the application"
appOptions = "[-server " + serverName + " -node " + nodeName
if len(appName) != 0:
appOptions = appOptions + " -appname " + appName +" -contextroot " + appName
appOptions = appOptions + " -defaultbinding.virtual.host default_host -usedefaultbindings]"
print "Server Options: " + appOptions
AdminApp.install(app, appOptions)
#--------------------------------------------------------------
# Save all changes and stop the server
#--------------------------------------------------------------
print "Now saving all the configurations"
AdminConfig.save()
print "Now stoping the server"
AdminControl.stopServer(serverName, nodeName)
#-----------------------------------------------------------------
# Main
#-----------------------------------------------------------------
if (len(sys.argv) != 3):
print "This script requires 3 parameters:
print "e.g.: argsDeployWARfile.py C:/Krish/SimpleJ2E_1.0.0.war SimpleJ2E server1"
else:
application = sys.argv[0]
appName = sys.argv[1]
print "application: " + application
print "app name: " + appName
nodeName = AdminControl.getNode()
print nodeName
serverName = sys.argv[2]
print serverName
install(serverName, nodeName, application, appName)
hi
'''
Created on Jan 18, 2012
@author: krishna
'''
#-----------------------------------------------------------------
# Main
#-----------------------------------------------------------------
if (len(sys.argv) != 2):
print "This script requires 1 parameters:, "
print "e.g.: undeployWAR.py SimpleJ2E server1"
else:
appName = sys.argv[0]
print "application name: " + appName
serverName = sys.argv[1]
print "Server Name: " + serverName
nodeName = AdminControl.getNode()
AdminApp.uninstall (appName)
print "Now saving all the configurations"
AdminConfig.save()
print "Now stopping the server"
AdminControl.stopServer(serverName, nodeName)
'''
Created on Jan 18, 2012
@author: krishna
'''
#-----------------------------------------------------------------
# Main
#-----------------------------------------------------------------
if (len(sys.argv) != 2):
print "This script requires 1 parameters:
print "e.g.: undeployWAR.py SimpleJ2E server1"
else:
appName = sys.argv[0]
print "application name: " + appName
serverName = sys.argv[1]
print "Server Name: " + serverName
nodeName = AdminControl.getNode()
AdminApp.uninstall (appName)
print "Now saving all the configurations"
AdminConfig.save()
print "Now stopping the server"
AdminControl.stopServer(serverName, nodeName)
The below is a simple HTML code containing JAVA script to use the object XMLHttpRequest to retrieve the contents of a weburl when GET is applied. Simple to say do HTTP GET and show the contents of URL.
References:
[1] [2]
Note : working only on Internet Explorer
<html>
<head>
<script type="text/javascript">
function loadXMLDoc()
{
if (window.XMLHttpRequest)
{// code for IE7+, Firefox, Chrome, Opera, Safari
xmlhttp=new XMLHttpRequest();
}
else
{// code for IE6, IE5
xmlhttp=new ActiveXObject("Microsoft.XMLHTTP");
}
xmlhttp.onreadystatechange=function()
{
alert('Http State is:' + xmlhttp.readyState);
alert('HTTP Status is :' + xmlhttp.statusText);
if (xmlhttp.readyState==4 )
{
if ( xmlhttp.status==200 )
{
alert('Response data as String :' + xmlhttp.responseText);
alert('Response data as XML:' + xmlhttp.responseXML);
}
}
}
try {
xmlhttp.open("GET","http://www.krishnababug.com/",true);
xmlhttp.send("");
}
catch (e) {
alert(e);
}
}
</script>
</head>
<body>
<h2>How to use XMLHttpRequest object</h2>
<div id="myDiv"></div>
<button type="button" onclick="loadXMLDoc()">Load URL - Click to change state</button>
</body>
</html>
<head>
<script type="text/javascript">
function loadXMLDoc()
{
if (window.XMLHttpRequest)
{// code for IE7+, Firefox, Chrome, Opera, Safari
xmlhttp=new XMLHttpRequest();
}
else
{// code for IE6, IE5
xmlhttp=new ActiveXObject("Microsoft.XMLHTTP");
}
xmlhttp.onreadystatechange=function()
{
alert('Http State is:' + xmlhttp.readyState);
alert('HTTP Status is :' + xmlhttp.statusText);
if (xmlhttp.readyState==4 )
{
if ( xmlhttp.status==200 )
{
alert('Response data as String :' + xmlhttp.responseText);
alert('Response data as XML:' + xmlhttp.responseXML);
}
}
}
try {
xmlhttp.open("GET","http://www.krishnababug.com/",true);
xmlhttp.send("");
}
catch (e) {
alert(e);
}
}
</script>
</head>
<body>
<h2>How to use XMLHttpRequest object</h2>
<div id="myDiv"></div>
<button type="button" onclick="loadXMLDoc()">Load URL - Click to change state</button>
</body>
</html>
References:
[1] [2]
Note : working only on Internet Explorer
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