Extracting JAR files and reading their contents

Hi,
I have a JAR files which contains classes in different packages also a config file which is also in some package structure.
I have to read that config file, which will inturn have other file names, i have to read the filename and read the actual content of the file spcified in the config file.
Can some one help me out with a simple example... ?
I have tried with java.util.zip... I can read the name of all the files in JAR to any depth.. but couldn't open and read the required file.
Thanks in advance...
Thanks & Regards,
Gurushant Hanchinal

Hello you can see the content of a jar file with this line
jar tf filename.jarand extract with
jar xf filename.jar

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Accessing a file and reading its contents.

Hi all,
I created a Portal Application to access a file and display its contents in an iView .
But it showing the exception like "File Not Found".
In simple java application i could able to get the result. In portal application i couldn't .
I have given the full path of the file location.
I need a help regarding this?
Regards,
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IS the file on the portal server? It must be visible to the service user that runs the Java engine...

How to import a csv file and read in sap ui5?

Hi,
I want to import a file and read it contents to bind it to table.How to do it?
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I tried to do this all from within the application but found it easier to just start with a JSON file. But, you can use a JS library to convert your CSV into JSON from within the application like this one:
archan937/csonv.js · GitHub
I just converted my CSV to JSON. Once you have that, all you need to do is instantiate a model for it and bind to table.
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The UI5 demo kit is a good resource. I believe it'll be same/similar for SAPUI5:
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Extract text file from a folder and read the content

Hi
I have "n" no.of text files saved in a folder with automatically generated naming convention which include DD/MM/YYYY and also some measurement output value.
Eg: 1) Die_1_DUT_outputvalue_DD_MM_YYYY.txt
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In the above files part of the 2nd file naming convention same as the first file (i.e. Die_1_DUT and DD_MM_YYYY) whereas outputvalue is different and an additional string named ABC is appended.
Now I want to search the 2nd file based on matching the naming pattern with the 1st file (note: the outputvalue in the file name is different for both files) and so far followed this method
1) Use a list folder with *.txt pattern to search all the text files and the output is a 1D array
2) then use array to cluster and then flatten to XML function to have all the text file names as a string element (not 1D array)
3) then pass the output of the 2nd step to the sting match pattern and use a regular expression to get the required file name
4) send the output of the 3rd step to search 1D array to get the index and then get the file name and later use read text file to read the content of the text file
And I am stuck at the 3rd step while sending an input as the regular expression to match the pattern as the outputvalue in the namming convention of the above two files is different is there any way I can actually extract the filename/file?
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How to extract jar files into a folder in the local disk and then import?

hai forum,
will any one tell me how should i extract jar files into a location in my project folder and then how to import the class files for further usage?
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I will be graeateful if u could explain this a bit.
Do you want to say that i should craete instance of
ZipEntry like this
InputStream is =
jarFile.getInputStream(entry);
File inputFile = new
File("C:\\myclasses.data");
FileInputStream fis=
new FileInputStream(inputFile);No! You need to write the entry using FileOutputStream copying all the bytes of the ZipEntry InputStream to the FileOutputStream.
>
What about adding into a directory?Do i have to
create on dynamically?Yes! You can use File.mkdirs(). For example
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ofile.getParentFile().mkdirs();

Read from .txt file and output the content as two arrays

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Hi Awen,
This is quite easy to do, you can merely use the "read from spreadsheet file" function to get a 2D array (2 columns and n rows) and then use the index array function to get whatever row/colums you want..
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Can a servlet read a jsp file and display its contents?

Hi,
I would like to know if Servlets can read a Jsp file and display its contents.. Right now for our website, I am using a html file to be displayed after a successful post operation through the Servlets...
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I posted this in another thread.
Here's some code that reads using a URL. This doesn't work with JSPs as the server executes JSP when it connects but it's useful for other file types. Note that the filename is a URI</h1>This is <code>show.jsp</code></h1>
<hr>
<%! String file = null; %>
<%! java.io.InputStream is = null; %>
<%
file = request.getParameterValues("filename")[0];
try {
is = (new java.net.URL(file)).openStream();
} catch (java.io.IOException ioe) { out.write(file + " not found!<br>"); }
java.io.BufferedReader in = new java.io.BufferedReader(new java.io.InputStreamReader(is));
String line = "";
%>
<pre>
<%
while((line = in.readLine()) != null) {
%>
<%=line%>
<%
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JAR files and getResource()

Hello i have the following piece of code in class x.y.z.Tester:
String rootPath = this.getClass().getResource("/").getPath();
System.out.println(rootPath);which prints the path where the x.y.z.Tester class is located on my FS.
for example if my class is store at:
C/folder_1/bin/x/y/z/Tester.class
the returned path would be:
C:/folder_1/bin
Now, when I bundle this class (along with others) in a JAR file and set the x.y.z.Tester as the main class and run it, i get this error:
Exception in thread "main" java.lang.NullPointerException
at com.nortelnetworks.productsupportability.netrx.service.report.generator.Tester.<init>(Tester.java:9)
at com.nortelnetworks.productsupportability.netrx.service.report.generator.Tester.main(Tester.java:35)
On line 9 is the first line of code above.
On line 35 is the call to the method that has line 9.
However, the funny thing is that when I unzip (or extract) the contents of my JAR file, the it works fine and returns the path where the x.y.z.Tester is stored.
Now, I would like to have this work without having to unzip the JAR file. does anyone know if any issues or why the "getResource()" method returns a NullPointerException if it's JAR'ed.
thank you,

Not sure what your goal is, but try this.
import java.net.URL;
import java.security.CodeSource;
import java.security.ProtectionDomain;
public class CodeSourceExample {
    public static void main(String[] args) {
        CodeSourceExample object = new CodeSourceExample();
        Class cls = object.getClass();
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        CodeSource source = domain.getCodeSource();
        URL location = source.getLocation();
        System.out.println(location);
}

To add the JNI dll to the jar file and use the dll inside the jar file

Hi to everybody,
I am new to java.
I want to add the JNI dll to the jar file and use it in the java class.
How can I achieve it.
Please help me.
Thanks in advance.
Regards,
M.Sivadhas.

can't be done because none of the known operating systems support reading binary libraries from .jar files ... you can add the binary to the jar but then you have to extract it...
besides, mixing platform specific and platfrom independent components is not a very good idea, i'd keep the dll out of the jar to begin with

Execution from JAR files and Classpaths -- Help

I am confused about how classes are resolved when running from within a JAR file, and why this is different than running a class that is not inside a JAR file.
I have an application that uses classes from a third party library stored in a JAR file (biojava.jar) . If I run the app from the class file it works as expected and is capable of finding the external classes when the path to the biojava.jar is on my classpath. It also works if biojava.jar is instead placed in the extensions folder jre/lib/ext folder without an explicit path entry in my classpath.
However when I package all my application classes up in a JAR file and try to execute the application from the JAR file it will ONLY work if I add a manifest entry to myApp.jar ... Class-Path: biojava.jar AND I place the file biojava.jar in the SAME directory as the Packaged JAR application. I would like to find a way to make this JAR file work for anyone who has biojava.jar in their classpath or ext directory. In other words I don't want my user community to have to copy the biojava.jar file when I email them myApp.jar. This community will already have biojava.jar on their CLASSPATH.
How can I make my app within a JAR recognize either the user's CLASSPATH or ext folder? I have tried reading the documentation and many experiments but the only way it works is as described above.
I am running Running Windows 2000.
java version "1.4.1_01"
Java(TM) 2 Runtime Environment, Standard Edition (build 1.4.1_01-b01)
Java HotSpot(TM) Client VM (build 1.4.1_01-b01, mixed mode)
Here are the results of my experimentations:
The following Works:
Manifest: Main-Class: org/biojava/app/SequenceSpiral
Manifest: Class-Path: biojava.jar
Place biojava.jar in the same directory as SequenceSpiral.jar
java -jar SequenceSpiral.jar
This works perfectly
NONE of the following work
0) Placing biojava.jar in my jre/lib/ext directory instead of the same dir as SequenceSpiral.jar
Exception in thread "main" java.lang.NoClassDefFoundError: org/biojava/bio/seq/FeatureFilter
(this is the first class referenced from biojava.jar)
1) Just see if it will find the proper jar on my classpath
Manifest: Main-Class: org/biojava/app/SequenceSpiral
I have biojava.jar on my classpath but not in same directory as SequenceSprial.jar
java -jar SequenceSpiral.jar
Exception in thread "main" java.lang.NoClassDefFoundError: org/biojava/bio/seq/FeatureFilter
2) Specify the name if the jar in the Manifest Classpath and see if it will find the proper jar on my classpath
Manifest: Main-Class: org/biojava/app/SequenceSpiral
Manifest: Class-Path: biojava.jar
I have biojava.jar on my classpath but not in same directory as SequenceSprial.jar
java -jar SequenceSpiral.jar
Exception in thread "main" java.lang.NoClassDefFoundError: org/biojava/bio/seq/FeatureFilter
3) Specify the path of the jar in the Manifest Classpath
Manifest: Main-Class: org/biojava/app/SequenceSpiral
Manifest: Class-Path: d:/biojava/biojava.jar
I have biojava.jar on my classpath (D;\biojava\biojava.jar) but not in same directory as SequenceSprial.jar
java -jar SequenceSpiral.jar
Exception in thread "main" java.lang.NoClassDefFoundError: org/biojava/bio/seq/FeatureFilter
(note that in this case it is not fnding my main even though the Main-Class is specified)
4) Specify current directory and biojava.jar in the Manifest Class-Path
Manifest: Main-Class: org/biojava/app/SequenceSpiral
Manifest: Class-Path: .;biojava.jar
I have biojava.jar on my classpath (D;\biojava\biojava.jar) but not in same directory as SequenceSprial.jar
java -jar SequenceSpiral.jar
Exception in thread "main" java.lang.NoClassDefFoundError: org/biojava/bio/seq/FeatureFilter
5)Specify current directory and the URL of biojava.jar in the Manifest Class-Path
Manifest: Main-Class: org/biojava/app/SequenceSpiral
Manifest: Class-Path: . d:/biojava/biojava.jar
I have biojava.jar on my classpath (D;\biojava\biojava.jar) but not in same directory as SequenceSprial.jar
java -jar SequenceSpiral.jar
Exception in thread "main" java.lang.NoClassDefFoundError: org/biojava/bio/seq/FeatureFilter.
Thank you very much for any help or suggestions,
David Maynard

I did some more testing and I think I now understand what is going on.
I don't like it, but at least I understand it.
The problem: I have an app packaged into a JAR file, myApp.jar. It has a dependancy upon an external JAR file extern.jar.
extern.jar is on my Classpath (and also in jre/lib/ext)
1) For some reason (bug?) java -jar myApp.jar does NOT use the classpath or the jre/lib/ext mechanisms to find .jar files needed to resolve references to external classes. This seems to be true even if you add an explicit -classpath argument on the command line!
thus
java -jar -cp c:\\absolutePathToMy\extern.jar myApp.jar
also fails as does
java -cp c:\\absolutePathToMy\extern.jar -jar myApp.jar
2) Inside the myApp Jar file you can specify a URL to an jar extension jar file but the URL IS RELATIVE TO THE PATH WHERE THE myApp.Jar is executed from! If I add the Manifest item Class-Path: ..\..\..\myexterndir\extern.jar then
java -jar myApp.jar
works correctly and resolves the external references.
This is why several people have reported that this class-path mechanism works ONLY when the extern.jar file is in the SAME DIRECTORY as the myApp.jar file when they had added a Class-Path: extern.jar to the Manifest.
However together these two items make it IMPOSSIBLE to distribute myApp.jar to others and have it work since the path names statically encoded inside the jar are relative to where the jar gets executed from. If I move myApp.jar to a different location on my hard drive it may also fail.
In my case I know all my customers already have extern.jar (5MB) installed on their classpaths and I would like to just send them the myApp.jar ( .5MB ).
However I don't see how to do this given the current specification of a JAR file, and the bug that makes all -jar file act like they have the Sealed=true property.
I tried explicity setting Sealed=false in the manifest but this didn't seem to have any effect.
I hope that this will save others the many hours of time it has taken be to determine that JARS are not well suited for deploying apps with dependenncies on external libs.
I also hope that someone can show me how execute a JAR and specify a classpath that doesn't get IGNORED my the classloader used in loading the jar classes.
This is using java version:
java version "1.4.1_01"
Java(TM) 2 Runtime Environment, Standard Edition (build 1.4.1_01-b01)
Java HotSpot(TM) Client VM (build 1.4.1_01-b01, mixed mode)
Does any one know this bug is fixed in a later release?
David Maynard

Executable jar files and manifest file

Hi,
I have the following files in a folder named: Test
a.jar
b.jar
c.jar
Driver.class
Driver.mf
Here, MainClass is the main executable class that uses a,band c.jar files. This is how my MainClass.mf file looks:
Manifest-Version: 1.0
Main-Class: Driver
Class-Path: a.jar b.jar c.jar
Now I use the following command to make one executable jar file:
jar cmf Driver.mf DriverMain.jar *
It creates an executable jar file named : DriverMain.jar
Now I copy the executable jar file (DriverMain.jar) into a different folder named: RunTest
and double click it, doesn't work.
my question is:
what am I doing wrong? Any special characters needed in my Driver.mf file (space/newline/etc)?
What I am trying to get is: One execuatble jar file so I can just double click to run it, and that single executable jar file will have all the necessary jars in it (i.e. a.jar, b.jar, c.jar in this case)
Anyone please help!
Thanks
-Ron

Rony,
Sorry to disappoint, but you can not use embeded jar/zip files within an executable jar. The JDK sadly for some reason decided this was not a useful idea, so developers like me who want to distribute plugins with thier own dependencies have one of two choices. You either have to unzip the jar file that contains the embeded jars to a directory, then run your primary exectuable jar, OR you have to write a custom classloader that your "launcher" creates then loads the embeded jar files.
The best thing to do is either jar up a, b, c and driver into one jar, so that it works, if you can legally do this. A lot of 3rd party libraries may not allow this per their license. Otherwise, another choice is to use a free installer or buy an installer that allows you to distribute a single exectuable installer program that will properly create the dir structure you need.
As for the way it works, if you declare:
Class-Path: a.jar b.jar c.jar
the JAR loader code in the JDK looks in the root dir where your application was started for a/b/c jar files. They have to be on disk.
If you want to place them in /lib, for example, you would havd a jar file like:
Driver.class
Driver.mf
lib/a.jar
lib/b.jar
lib/c.jar
When unzipped, your "root" dir would look exactly like the above, and your manifest would have Class-Path using ./lib/a.jar ./lib/b.jar ./lib/c.jar
Anyway, there thus far isn't any way around this issue of embeding jar files in an executable jar file. You MIGHT be able to not specify any classpath, then in your Driver.class, create a new custom classloader that dervies from URLClassLoader, but in the findClass(), you get a ref to the .jar file that the classloader class is inside of, and from that use it to find the lib/*.jar files and add them to the classpath. For this to work, however, your Driver.class code should ALSO be contained in an embeded jar file that is loaded by this custom loader. The only thing Driver.class would contain (and I would rename it to something like Launcher) is the code to create the custom classloader.
It's fun stuff, but a little bit of work to make it work. You can infact make it work! I may yet one day take our plugin engine custom loader and create a way for this to work!

Read a csv file and read the fiscal yr in the 4th pos?

Hello ABAP Experts,
how to write a code for read a csv file and read the fiscal year in the 4th position.
any suggestions or code highly appreciated.
Thanks,
BWer

Hi Bwer,
Declare table itab with the required fields...
Use GUI UPLOAD to get the contents of the file (say abc.csv) in case if the file is on the presentation server...
CALL FUNCTION 'GUI_DOWNLOAD'
EXPORTING
    filename                        = 'c:\abc.csv'
   FILETYPE                        = 'ASC'
    WRITE_FIELD_SEPARATOR           = 'X'
tables
    data_tab                        = itab
EXCEPTIONS
   FILE_WRITE_ERROR                = 1
   NO_BATCH                        = 2
   OTHERS                          = 22
IF sy-subrc <> 0.
MESSAGE ID SY-MSGID TYPE SY-MSGTY NUMBER SY-MSGNO
         WITH SY-MSGV1 SY-MSGV2 SY-MSGV3 SY-MSGV4.
ENDIF.
Use OPEN DATASET in case if the file is on the application server..
After that USE SPLIT command at comma to get the contents of the 4th field...
Regards,
Tanveer.
<b>Please mark helpful answers</b>

How to create a file and store its contents into another file?

Hi,
I'm having some trouble trying to create a code where I have to to create a file and store its contents into another file?
I read the API, but I'm not certain how this file thing works.
Here's my code so far:
public static void main(String[] args) throws Exception
          File file = new File("tasks.txt");
          if (file.exists())
               System.out.println("File already exists");
               System.exit(0);
          Scanner scan = new Scanner(System.in);
          Scanner scan2 = new Scanner(System.in);
          //Scans the input line by line
          scan.useDelimiter("\\n");
          //Scans the input by tabs
          scan2.useDelimiter("\\t");
          PrintWriter outputs = new PrintWriter("newtasks.txt");
          outputs.print("ok");
          outputs.println(3);
          outputs.close();
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I managed to change my text into uppercase, but how do I store the uppercase content into another file.
-So this is what I did so far, I took a text file and modified its strings to uppercase.
-Now I need to put those modified strings into another text file, is there a way where I can do that with my current code?
-I already tried printwriter, but it doesn't seem to work
public static void main(String[] args)throws IOException
          //Task[] oneHundredTasks = new Task[100];
          String uppercase;
          String combine;
          Scanner scan = null;
          FileInputStream in = null;
        FileOutputStream out = null;
        PrintWriter output = null;
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             scan = new Scanner(new BufferedReader(new FileReader("tasks.txt")));
             scan.useDelimiter("\\n");
             scan.useDelimiter("\\t");
            while (scan.hasNext())
                 if(!scan.hasNext())
                      scan.next();
                 combine = scan.next();
                 uppercase = combine.toUpperCase();
                 System.out.println(uppercase);
        finally
            if (scan != null)
                scan.close();
        //The program will try the input and output files
        try
             in = new FileInputStream("tasks.txt");
            out = new FileOutputStream("newtasks.txt");
            int c;
            //The number "-1" is used to indicate that it has reached the end of the stream.
            while ((c = in.read()) != -1)
                out.write(c);
        finally
            if (in != null)
                in.close();
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Jar files and Main-Class attribute

Sorry, I know there are other topics regarding this argument but none of them helped me solving my problem.
I've tried a thousand time in every possible way, but I still can't run my application from a jar file. I've got a package called client, whose main class is called Client. The package contains a sub-package called Icons. I've put everything into a jar file and added this manifest:
Manifest version: 1.0
Name: client/
Sealed: True
Main-Class: client.Client
But it won't work. I've tried to erase the Sealed part, I've tried "Main-Class: Client" and also "client/Client", I've tried putting into the jar the client directory and I've tried omitting it, but the answer is always the same:
Failed to load main-class header etc.
Can anyone help me? Please, I'm almost desperate!
Thanks

Here's the verbose-mode description of what I did.
jar -cfv client.jar clientaggiunto manifesto
aggiunta in corso di: client/(in = 0) (out= 0)(archiviato 0%)
aggiunta in corso di: client/.nbattrs(in = 767) (out= 310)(compresso 59%)
aggiunta in corso di: client/Client.class(in = 533) (out= 340)(compresso 36%)
aggiunta in corso di: client/Client.java(in = 288) (out= 140)(compresso 51%)
aggiunta in corso di: client/ClientForm$1.class(in = 691) (out= 383)(compresso 44%)
aggiunta in corso di: client/ClientForm$10.class(in = 678) (out= 380)(compresso 43%)
aggiunta in corso di: client/ClientForm$11.class(in = 689) (out= 385)(compresso 44%)
aggiunta in corso di: client/ClientForm$2.class(in = 686) (out= 379)(compresso 44%)
aggiunta in corso di: client/ClientForm$3.class(in = 686) (out= 381)(compresso 44%)
aggiunta in corso di: client/ClientForm$4.class(in = 686) (out= 380)(compresso 44%)
aggiunta in corso di: client/ClientForm$5.class(in = 686) (out= 383)(compresso 44%)
aggiunta in corso di: client/ClientForm$6.class(in = 718) (out= 399)(compresso 44%)
aggiunta in corso di: client/ClientForm$7.class(in = 718) (out= 400)(compresso 44%)
aggiunta in corso di: client/ClientForm$8.class(in = 718) (out= 399)(compresso 44%)
aggiunta in corso di: client/ClientForm$9.class(in = 718) (out= 398)(compresso 44%)
aggiunta in corso di: client/ClientForm.class(in = 33070) (out= 13510)(compresso 59%)
aggiunta in corso di: client/ClientForm.form(in = 131398) (out= 4521)(compresso96%)
aggiunta in corso di: client/ClientForm.java(in = 73435) (out= 6863)(compresso 90%)
aggiunta in corso di: client/Icons/(in = 0) (out= 0)(archiviato 0%)
aggiunta in corso di: client/Icons/brick.gif(in = 1044) (out= 1049)(compresso 0%)
aggiunta in corso di: client/Icons/corpo.gif(in = 4011) (out= 3400)(compresso 15%)
aggiunta in corso di: client/Icons/door.gif(in = 1092) (out= 1097)(compresso 0%)
aggiunta in corso di: client/Icons/floor.gif(in = 1102) (out= 1107)(compresso 0%)
aggiunta in corso di: client/Icons/mappa.gif(in = 20901) (out= 20575)(compresso 1%)
aggiunta in corso di: client/Icons/paesaggio.gif(in = 18962) (out= 18603)(compresso 1%)
aggiunta in corso di: client/Icons/sole.gif(in = 7063) (out= 6546)(compresso 7%)
aggiunta in corso di: client/Icons/trap.gif(in = 1062) (out= 1067)(compresso 0%)
aggiunta in corso di: client/Icons/void.gif(in = 842) (out= 847)(compresso 0%)
aggiunta in corso di: client/Listener.class(in = 1869) (out= 1136)(compresso 39%)
aggiunta in corso di: client/Listener.java(in = 2296) (out= 708)(compresso 69%)
aggiunta in corso di: client/manifesto.txt(in = 62) (out= 58)(compresso 6%)
aggiunta in corso di: client/ScorciatoieDialog$1.class(in = 740) (out= 391)(compresso 47%)
aggiunta in corso di: client/ScorciatoieDialog$PopupListener.class(in = 1579) (out= 773)(compresso 51%)
aggiunta in corso di: client/ScorciatoieDialog.class(in = 3524) (out= 1638)(compresso 53%)
aggiunta in corso di: client/ScorciatoieDialog.form(in = 8500) (out= 910)(compresso 89%)
aggiunta in corso di: client/ScorciatoieDialog.java(in = 5676) (out= 1222)(compresso 78%)
jar umf mainclass.txt client.jar[NOTE: mainclass.txt only contains the line "Main-Class: client.Client"]
java -jar client.jarFailed to load Main-Class manifest attribute from
client.jar
I've also tried to manually create a MANIFEST.MF file that only contained the following lines:
Manifest Version: 1.0
Main-Class: client.Client
guess what was the result?
java -jar client.jarException in thread "main" java.io.IOException: invalid manifest format
at java.util.jar.Manifest.read(Manifest.java:193)
at java.util.jar.Manifest.<init>(Manifest.java:52)
at java.util.jar.JarFile.getManifest(JarFile.java:158)
>
the same procedure with the addition of "Name: client/" before the main-class attribute generated the usual "Failed to load Main-Class manifest attribute" result. So now what?!? I'm getting crazy....

Creating & Using .jar files and manifests

I've read through hundreds of online tutorials on creating and using .jar's, but it's surprising how unhelpful they really are.
I've been trying to make a java program of mine standalone, so I can distribute it to others and allow them to run it without use of a compiler, etc (ideally just a .exe or .bat that they double click on). Everything I've found says I need to create a .jar of my program in order to do this. I was finally able to create a .jar but I got different errors relating to "main-class" and "manifest" issues...I tried running it with javaw.exe and had the same problem.
Some tutorials briefly discuss "meta manifest's", other's skip the concept all together in creating .jar's. I created a jar with:
jar cf A2.jar c:\jarTester.java
after changing my command prompt path to
C:\Program Files\Java\jdk1.6.0_01\bin
It created the .jar, but nothing worked. As above, it gave me errors relating to the "Main-Class" and "Manifest". So here's my question:
What involvement does a "manifest" play in .jar's, and how do I create/use one to create a .jar? Why is it necessary to specify the "Main-Class" when I have already done so in my .java file?
I believe that once I can get this "Main-Class" and "Manifest" problem straightened out, I will be able to create a batch file with the line:
java -jar A2.jar
is this correct? THANKS.

I've read through hundreds of online tutorials on
creating and using .jar's, but it's surprising how
unhelpful they really are.really, hundreds?
I've been trying to make a java program of mine
standalone, so I can distribute it to others and
allow them to run it without use of a compiler, etc
(ideally just a .exe or .bat that they double click
on). Everything I've found says I need to create a
.jar of my program in order to do this. Make up your mind, do you want to make a jar or an exe?
I was
finally able to create a .jar but I got different
errors relating to "main-class" and "manifest"
issues...I tried running it with javaw.exe and had
the same problem.
Some tutorials briefly discuss "meta manifest's",
other's skip the concept all togetherthat's because the manifest isn't usually necessary
in creating
.jar's. I created a jar with:
jar cf A2.jar c:\jarTester.javaugh, that won't work. you need to put the class file in there, not the source. or you can put the source in as well if you want, but the class is necessary
i'm ignoring the rest of this post for now
go back to Google and type in jar manifest and read more

Extracting JAR files and reading their contents

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