.Jar to Java code

Hello,
I've recently found out some old jar files that i had created and i need to reverse them to get the (well, almost) original java code that i had wrote.
Is there any way to do this?
Thanks in advance

Google java decompiler
http://www.google.com/search?hl=en&q=java+decompiler&btnG=Google+Search

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Verifying signed Jar using Java code

Hi,
I have been looking for a way to verify signed or unsigned jar from java code.
I have to use the jar name and from here, I have to verify the digital signature. For this goal I have found some Java classes which can be useful for me. These classes would be JarEntry class, from which I could get the certificates. Signature class, whose methods let me verify the digital signatures, and Certificate class. I also found a class called SignedObject from I could get the signature data which the method getSignature (), but the problem here it is that I need a private key in the SignedObject constructor, which is not possible since I want to verify a signed jar which I am not able to know the private key, just public key. So, could anybody tell me how I could solve this problem?
My code would be some as shown below:
jar = new JarEntry (location);
          jarcertificates = jar.getCertificates();
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I guess that I have to use jar.getExtra () in order to get the data to put in Signature.update() method but I am not sure, am I wrong?
Thanks in advance

Here is some sample code to verify a jar file:
        JarFile jf = new JarFile(args[0], true);
        byte[] buffer = new byte[8192];
        Enumeration e = jf.entries();
        ArrayList entries = new ArrayList();
        while (e.hasMoreElements()) {
            JarEntry je = (JarEntry) e.nextElement();
            entries.add(je);
            InputStream is = jf.getInputStream(je);
            while (is.read(buffer, 0, buffer.length) != -1) {
                // we just read. this will throw a SecurityException
                // if a signature/digest check fails.
            is.close();
        }To validate the certificate chain, you can call JarEntry.getCertificates(), create a CertPath from the array of Certificates (using a CertificateFactory), and then use the CertPathValidator APIs. For more information, see the PKI Programmer's guide: http://java.sun.com/javase/6/docs/technotes/guides/security/certpath/CertPathProgGuide.html

Executing jar from java code, then kill parent java code

Please suggest if there is any best way around on executing jar from java code then killing parent java code.
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b) How can I START external java application say "execute.jar" from Monitor.java THEN EXIT Monitor.java
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Try2) Runtime r = Runtime.getRuntime();
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I have a requirement to transfer data from one db to another db from Java Application Layer.Maybe, maye not. We get all sorts of weird "requirements" - which are nothing but thoughts or proposed solutions.
But,
Did the "requirement" mention whether the table existed already or not in the target database? - If not, did it tell you to create it - drop/create it?
Did the "requirement" deliver some explanation to why this copying was neeeded? - Are we talking replication? - Or a one time cloning?
Etc, etc,
Personally I would always argue against a "reuirement" like that. - It just isn't the way to do it. Period.
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You might want to take a look at service providers:
http://java.sun.com/j2se/1.4.2/docs/guide/jar/jar.html#Service%20Provider

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phychem wrote:
i want to use this jar in a non-static way.
public void useJar(String args[]){
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Sorry, I still don't get it. I don't know what you mean by a non-static way of using jars. The main method for launching an application is static so if you call that method, you will be using a static method. I don't know what you mean by a "jar method" either. Methods are inside classes. So far, all I can guess is you want to invoke a method in a class that happens to be inside a jar. Since people do this all the time without reflection, I don't see the problem.

Running .jar files from Java code

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I am designing a sort of platform to run some games which are saved in .jar files. Basically this platform is a menu from which the user can select the game which he/she wants to run. It also has the feature of adding new games.
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My CDC application run in Windows Mobile, with Creme JVM.
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Edited by: FabioPinheiro on Mar 28, 2008 4:41 AM

Hi all,
The Mr. Rene (from NSIcom) answer my question
Just
Add flag -mi.
(multiple instance)
I try and work fine.
thanks Rene..
Fabio

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Hi all,
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I notice that in the "Assets" there are "Databanks","Object Libraries","JAR Files","Scripts". Since the databanks and scripts that added to "Databanks" and "Scripts" can be got or run in Java Code like:
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*or getScript("ScriptName").run();*
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Thank you very much!
Regards,
Angyoung

Hi DM,
Thanks for your reply!
I've found a workaround,which is calling OpenScript's APIs ,such as this.getScriptPackage().getRepository() and this.getScriptPackage().getWorkspace(),etc to locate the .jar file.
And this workaround can still work even though the script is run on other machine.
Sorry to reply you so late!
Regards,
Angyoung

Some java code returns a null resultset from 10.2.0.1 DB, but works w/ 9.2

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Hello,
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Hussien,
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.Jar to Java code

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