Load a file stored in a Jar Archive

Dear all,
I have a text file stored in a Jar Archive and I want to obtain a File instance of the text file from the jar file. The reason for this is because I have a method which read in a File instance of the file.
From my understanding, one can obtain an byte[] array from a file stored in a text file. Is there a way to convert the byte[] into a File instance?
Thanks.
Sunny

Once again, thank you for your prompt response. I agree that one can obtain an inputstream of a file from the Jar archive and work with it. The problem that I am having is that the method that I have is not written by me, to be precise, I am using Syslog and try to read in a configuration file packed in a Jar Archive. The Syslog library only provide a method, which only accept a 'File' instance as an input argument.
Thanks.
Sunny

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How to access a xml file stored in a jar file

Hi all,
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Best Regards,
Jambor
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Can I refer to a file insider a .JAR archive with an instance of File?

Hi,
I was wondering if it is possible to refer to a file stored inside a .JAR file just as if it was on a regular folder by using an instance of the java.io.File class. Otherwise, how can one do that?
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http://java.sun.com/j2se/1.4.2/docs/api/java/util/jar/JarFile.html
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Hi,
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if (!efile.exists()) {
//get an input stream for the database file
InputStream in = new BufferedInputStream(this.getClass().getClassLoader().getResourceAsStream(
"FaST/db/steelSections.mdb"));
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OutputStream out = new BufferedOutputStream(new FileOutputStream(efile));
//-Buffer to copy the data
byte[] buffer = new byte[2048]; //buffer to copy the binary
for (;;) {
int nBytes = in.read(buffer); //read data
if (nBytes <= 0)
break; //no more data to read
out.write(buffer, 0, nBytes); //write data
out.flush(); //close out and in streams
out.close();
in.close();
If you have the db file in an other jar archive file you need a referenze to the entry in the other jar archive. I'm not sure how to get this, but I'm sure you fill find a solution by searching in this forum...
Good luck!

Load xml file using gerResource() from a class in jar

Hi,
I have a jar file. I set the classpath for the jar.
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ex: /example/test.jar (jar file)
/example/test/test.xml
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Test.class is in the jar.
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Try
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[url http://java.sun.com/j2se/1.4.2/docs/api/java/lang/Class.html#getProtectionDomain()]http://java.sun.com/j2se/1.4.2/docs/api/java/lang/Class.html#getProtectionDomain()
http://java.sun.com/j2se/1.4.2/docs/api/java/security/ProtectionDomain.html
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Security restrictions , how to read access a txt file supplied in a jar

I had written a simple application which uses file handling to display random line from a file on a swing window
but I do not know how to give my web application permission to access a file
when I set security permission to all, then error says the application cannot load because the code require unrestricted acess to system resources and is unsigned, I don't know how to get that certificate and I am only doing it for learning purposes.
when I remove security permissions then it says
access denied java.io.FilePermissions geekjoskes.txt readPlease help
I locally signed the jar file, and give my jnlp fiel all permissions, worked fine in my system but when I access same file from local lan it sho errors ,
please help, I have my txt file stored in my jar file with main class
the whole jnlp file is
<?xml version="1.0" encoding="utf-8"?>

<jnlp spec="1.0+"
       codebase="http://localhost/javasoft/webstart/"
      href="geekjokes.jnlp">
   <information>
      <title>Geek Jokes</title>
      <vendor>Vaibhav Mishra</vendor>
      <description>Geeky jokes</description>
      <homepage href="http://scjpbeginner.blogspot.com"/>
      <description kind="short">shows random jokes</description>
      <offline-allowed/>
   </information>
   <resources>
        <jar href="GeekJokes0.1.jar"/>
     <j2se version="1.6+"
           href="http://java.sun.com/products/autodl/j2se"/>
     <icon href="geekjokes.gif"/>
   <icon kind="splash" href = "geekjokes.gif"/>
   </resources>
   <security>
      <all-permissions/>
   </security>
   <offline-allowed/>
   <application-desc main-class="GeekJokes"/>
</jnlp>Edited by: 76jsr on Aug 7, 2008 3:45 PM
Edited by: 76jsr on Aug 7, 2008 3:49 PM

>
I am extremely thankful to you and finally my first little app is working thanks to you,
here is it's link
[http://profile.iiita.ac.in/IIT2006117/javasoft/webstart/geekjokes/geekjokes.jnlp|http://profile.iiita.ac.in/IIT2006117/javasoft/webstart/geekjokes/geekjokes.jnlp] >
I am glad you got it working! But that launch file is still slightly invalid.
Here is a corrected, and slightly optimized (you can leave the prefix off the href, if it is the same as the codebase), version of it.
<?xml version="1.0" encoding="utf-8"?>

<jnlp spec="1.0+"
      codebase="http://profile.iiita.ac.in/IIT2006117/javasoft/webstart/geekjokes"
      href="geekjokes.jnlp">
   <information>
      <title>GeekJokes App</title>
      <vendor>Vaibhav Mishra</vendor>
      <homepage href="http://scjpbeginner.blogspot.com"/>
      <description>Geeky Jokes</description>
      <description kind="short">Cshows random jokes</description>
      <offline-allowed/>
   </information>
   <resources>
       <j2se version="1.6+"
           href="http://java.sun.com/products/autodl/j2se"/>
       <jar href="GeekJokes0.3.jar"/>
   </resources>
   <application-desc main-class="Process"/>
</jnlp>Very 'Geeky', BTW. ;-)
Another few things I noted when I looked at it.
1) There is a stray thread going after the JOptionPane is dismissed. The VM does not end, and the console (if you have it configured to pop-up for JWS apps.) stays on-screen.
2) If all the jokes are prefixed by '* ' I would recommend removing it from every line of the source file and either re-adding it at runtime, or (preferably) not adding it at all (since it is redundant).
3) Reconfigure the app. into a loop, and offer the user a JOptionPane with "Another Joke"/"End" instead of "OK".
4) You can always remove that debugging line I inserted in the code to show the path to the Jar - it was just intended as a 'sanity check' during testing.
5) Why is it Java 1.6+? JOptionPane was introduced in Java 1.2 with the first Swing implementations, and the I/O is compatible with Java 1.1.
>
Thanks again!!!!>Thanks are best expressed (to me) in the notation of a helpful/correct answer (which you have done), and the assignation of (the remaining) dukes*. ;-)
* After all - checks the title - we have gotten entirely around those 'security restrictions' in a sandboxed application. The reason being that File objects are rarely the correct choice, for applets or JWS apps.

Tomcat6 does not load class files from WEB-INF/lib/myjarfile.jar WHY???

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ProcessFileUpload.java:4: package test.test1 does not exist
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As i unzipped my jar and placed the packagefolder structure to
c:\tomcat6\webapps\my-application\WEB-INF\classes\testand it works perfectly.
Anyone knows its workaround? please suggest if any configuration changes is required in tomcat or so.
Thanks.
---Sujoy

Thank you gimbal2 . There was error in creating the jar file myjarfile.jar.
But, now I have created it again and placed it in place
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I DO NOT WANT TO unzip the jar, placing all unzipped files to
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If you please see the small code bit and tell me any possible error that would be very helpful.
Step 1: my library java file MyClass.java
package test.test1;
public class MyClass {
     String myName = "Default return string value";
     public void setMyName(String varName) {
          this.myName = varName;
     public String getMyName() {
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}Step2 : Creating jar file of my library class files
C:\jdk1.6\bin>jar cvf myjarfile.jar test
added manifest
adding: test/(in = 0) (out= 0)(stored 0%)
adding: test/test1/(in = 0) (out= 0)(stored 0%)
adding: test/test1/MyClass.class(in = 452) (out= 296)(deflated 34%)
adding: test/test1/MyClass.java(in = 230) (out= 140)(deflated 39%)
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C:\jdk1.6\bin>jar tf myjarfile.jar
META-INF/
META-INF/MANIFEST.MF
test/
test/test1/
test/test1/MyClass.class
test/test1/MyClass.java
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import java.io.*;
import javax.servlet.*;
import javax.servlet.http.*;
import test.test1.*;
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          out.println(mc.getMyName());
}Step7 : Tried to compile my servlet LibFolderTest.java and got the following error
LibFolderTest.java:4: package test.test1 does not exist
import test.test1.*;
^
LibFolderTest.java:11: cannot find symbol
symbol : class MyClass
location: class LibFolderTest
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                ^
LibFolderTest.java:11: cannot find symbol
symbol : class MyClass
location: class LibFolderTest
                MyClass mc = new MyClass();
                                 ^
3 errorsThe above servlet compilation error on Step7 is telling me that myjarfile.jar is not loaded by Tomcat6 or not available for use when compiling servlet. I want to use myjarfile.jar from within WEB-INF\lib\ folder but I can not. please help.
---Sujoy

Access wav-files in jar-archives (URL works, File works not)

Hi there!
The un-jar-ed application works fine, but I have a problem with accessing files in jar archives.
URL url = Classname.class.getResource("testdir/test.wav");works fine (and loading images works this way), but as soon as I try to get the file
File file = new File(url.getFile());I get an null-exception.
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works fine Then keep doing it that way. What's the problem? It's true that you can't access something in a jar archive via a File object, so don't do that.

How to load all the classes in a JAR file at runtime?

Any clues o:
"How can I force JVM to load all the classes in a specified JAR at once?"
Thanx!
-Rajeev

Well I was thinking may be there exists an option with "java", when I
am starting an application from a jar file, I could force it to load all
the classes in the JAR. I don't want to do it programically. Is there such
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List all JarEntries and convert the paths to fully
qualified class files
e.g file in jar
[1] /com/mycompany/proj/X.class
should become
[2] com.mycompany.proj.X
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ClassLoader in JAR file not loading config file properly

Hi all,
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I have a method from a certain class that loads the configuration file. The class is not important, as it is part of an API that I cannot alter. This class has a load(String file) method, that loads the specified configuration file with a String argument. This works fine when I run my application from the command line and when the configuration file is not located in the JAR, but I need to include this configuration file in my JAR, so I can run my app in the JWS sandbox.
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Is there something I am doing wrong? Is this the wrong way to go about this?
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Message was edited by:
Djaunl

try this:
import java.io.*;
import java.util.jar.*;
import java.util.zip.*;
public class ExtractFromJAR {
     public void extractFileFromJAR(String dest, String fileName) {
          try {
               String home = getClass().getProtectionDomain().getCodeSource().getLocation().getPath().replaceAll("%20",
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               OutputStream out = new BufferedOutputStream(new FileOutputStream(efile));
               byte[] buffer = new byte[2048];
               for (;;) {
                    int nBytes = in.read(buffer);
                    if (nBytes <= 0)
                         break;
                    out.write(buffer, 0, nBytes);
               out.flush();
               out.close();
               in.close();
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}

Storing Icons in JAR Files

As per the optimization best practices for web deployed forms , Image Icons( which are GIF images) on the buttons can be placed in a JAR file so that it can be cached by the client side JVM . Can anybody help me out and tell me the steps of how to do it. Thanx in advance.

Sorry, you're correct it does need to be on the "archive_jini=" as well!
If your using rollover images, I found the best way to get these working was just to include them in the Rolloverbutton.jar file. I did this by loading the rolloverbutton project into JDeveloper, adding the icons into the project and re-deploying. There are some good notes at http://otn.oracle.com/formsupgrade to explain how to generate JPCs.
If your using standard Forms Iconic buttons...
Once your form has loaded, double click the Java Console Icon in the system tray, you should see lines that state;
Loading http://<myserver>/forms90/java/f90all_jinit.jar
Loading http://<myserver>/forms90/java/calendar.jar
Loading http://<myserver>/forms90/java/rolloverbutton.jar
Loading http://<myserver>/forms90/java/gs.jar
If these are loading ok, in the Java console hit the 5 key. Then re-load the form so that images are reloaded and check for lines that state;
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If it gives a different URL, then the imagebase must be set incorrectly.

Invisible class files inside jar archives

Hi!
After developing an application with J2SE 1.4.1_05, under Windows 98, using some packages archived in jar files, I cannot launch the application with the J2RE 1.4.2_02 or J2SE 1.4.2_02 (in the same Windows 98) because the class files in the jars are not 'visible', even if the CLASSPATH is set up correctly. The only classes that work right are the unpacked ones. But it still does work in Windows 2000.
What might be wrong?

Thank you for your answer, and excuse me if my question was kind of confusing.
The issue here is that the files ARE in the jar files (without './' on the front), but in the environment (Windows 98 + J2RE 1.4.2_02) the application does not work, unless I unpack the jars and use the packages in the same manner I did during the development stage (for example, all classes of package 'myutils' in the folder 'myutils').
The weird thing is that this DOES NOT happen in the environment (Windows 2000 + J2RE 1.4.2_02)!!! Just after installing the J2RE 1.4.2_02 under Win2K, the app does work OK! That is why it seems that ONLY in the first case (Windows 98 + J2RE 1.4.2_02) the class files inside the jars seem to be 'invisible' to the environment.
As I have mentioned in my question, the app was developed in the environment (Windows 98 + J2RE 1.4.1_05), and it did still work with the jar files, so I wonder if there might be some compatibility between Windows 98 and the J2RE 1.4.2_02.
Except my own jars, the same thing does happen with the jai_core.jar file coming with JAI 1.1.2. But this does not happen when it comes about rt.jar, in ..\jre\bin!!!
All in all, the question still is: what might be wrong?

Load a file stored in a Jar Archive

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