Free java class file has wrong version software for linux

The Java Binary Enhancement Tool (JBET) is a general Java program analysis and manipulation tool. Existing class files can be disassembled, reassembled, or edited programmatically through the JBET API. JBET can also be used to create new Java class files from scratch. JBET uses a convenient internal representation of all the contents of Java binary (.class) files, allowing the user to edit the classes easily, in a structured manner.

JBET was developed as part of the DARPA Self-Protecting Mobile Agents project under the OASIS and Active Networks programs (contract number N66001-00-C-8602) in order to study automated software obfuscation.

The Java language was chosen for this project because of the (relative) ease of constructing binary editing tools provided by the large amount of type information present in the class files. Our two reports, the Obfuscation Techniques Evaluation Report, and the Obfuscation Report, are available from the download area. The obfuscation tool developed is not part of this release.

JBET was also used in the DARPA/AFRL Survivable Server project (contract number F30602-00-C-0183) to add additional security checks to the Java Standard Library. (The Java SecurityManager API does not support many desirable security checks, such as continued authorization of file accesses after opening.)

JBET was used to replace the native method references in the Java standard library with stubs that call a pluggable security policy. This tool, called Jpolicy, is also available for download at this website. Jpolicy is very incomplete at this time, but may be interesting to those working in Java security or changing the standard library themselves.

The internal representation of Java class files used by JBET is intented to make it easy for programmers to write Java binary code transforms. Each element of Java class files has a corresponding internal data structure: ClassInfo for entire classes, MethodInfo for methods, FieldInfo for fields, Snippit for code blocks, and Instruction for individual instructions. Snippit and Instruction understand Java opcode syntax and semantics, allowing automated creation of valid Java programs. A Java-compatible class verifier is also included.

Some code transforms are difficult to program directly by manipulating Java instructions. For those transforms, a directed acyclic graph (DAG) representation of code is available. In the DAG representation, each basic block has a corresponding DAG, with a set of input and output nodes. Edges in the graph connect "producer" nodes (such as constants, or the result of calculations) to "user" nodes (such as method calls or other calculations). Methods are divided into basic blocks and control flow is stored at the basic block level (possible because Java has only fixed jump targets)

JBET requires a Java 1.4 virtual machine to run, although it can operate on class files from earlier Java versions. The packaging and build environment supplied supports Linux and Windows with Cygwin; however, the build process is simple and could be performed manually on other platforms. Perl is required for regression testing.

Jpolicy requires a Java 1.4 virtual machine to build, either Linux or Windows NT/XP with Cygwin. gcc is required for building on Windows (supplied with Cygwin). The runtime system can be either Java 1.3 or 1.4 (with Suns JVM only), running on Linux or Windows NT/XP. Windows 9x and Windows 2000 may work as well, but have not been tested.

Installation

1. Install jdk 1.4.1.
2. Set CLASSPATH to jdk1.4.1/jre/lib/rt.jar
3. cd src; make
4. If that didnt work, examine the makefile. java or javac may not be in the path.
5. To build a jar file that can be used with "java -jar jbet.jar", run "make jar".
6. If you have perl installed, run the tests with "make test".
Optionally, run "make regen; make test".

Make a symbolic link from jbet3/bin/jbet to somewhere in your path.

Usage

JBET uses the JNI format for class names, and JNI type and method descriptors. For a summary of this syntax, use jbet help syntax. Suns JVM specification may also be helpful.

To look at a class disassembly, use jbet print. Try disassembling a class you have source for, and was built with debug info (-g): jbet -P < classpath > print < classname >. Suns JVM specification has an instruction reference.

Java for C++ is a tool to generate C++-wrapper-classes for existing Java-classes. This tool reads a list of Java class names and creates source code for C++-classes to wrap them.
The implementation of the wrapper classes uses JNI (Java Native Interface) to call the "real" Java classes.
The C++-API to use these wrapper classes is very close to the API of the original Java classes. So developers of C++-software can use Java-classes as if they have been implemented in C++.
Enhancements:
- A problem where null values for method arguments, method return values, or field values caused some generated code to crash was fixed.
- Updating is strongly encouraged.

Access Modifier Eclipse Plug-in allows the user to change the visibility (public, protected, default, private) and other modifiers (final, static, synchronized) of Java classes, interfaces, methods and fields in the workbenchs Outline, Members and Package Explorer views.

The plug-in lets you modify the access modifiers of classes, interfaces, methods and fields through a popup menu. The following choices are available, each one changing the selected items visibility:

public public
protected protected
default default
private private

In addition to changing the visibility of the marked element, you can also set or unset the final, static and synchronized modifiers:

final/not final
static/not static
synchronized/not synchronized

Java::Import::Examples is an example of how to use Java::Import to call into Java classes.

Making RMI calls from Perl

One nice thing about Java is the extremely straight forward manner in which it allows you to make calls to remote objects residing on distant servers. Many people use this ability as a point of integration between their system and a posible third party or legacy system. Unfortunatly, for the most part the ability to make calls to these remote objects is something that only other Java applications can do without making a big fuss about it. However, we can now do this from Perl.

Assume that I have a RMI server from which I can get data from in the form of simple Java Beans. One method of doing this is to use the GCJ::Cni library and natively compile and wrap a set of Java Classes which can then be used from my Perl script. However, there is an easier way.

Lets begin by descriping the Java interfaces that well be working with. We first have the Remote Interface that we will be interacting with:

import java.rmi.*;
public interface RemoteInterface extends Remote {
public SomeBean getMessage(String seedMessage) throws RemoteException;
}
And we also have the bean we will be asking for:
import java.io.*;
public class SomeBean implements Serializable {
private String value;
public SomeBean() {}
public void setValue ( String _value ) { ... }
public String getValue ( ) { ... }
}
As far as any Perl client program is concerned this is all we need to know about.
Now all there is left to do is write a client:
use Java::Import qw(
java.rmi.Naming
);

my $remote_interface = java::rmi::Naming->lookup(jstring("//localhost/Home"));
my $bean = $remote_interface->getMessage(jstring("Hi there"));
print $bean->getValue(), "n";

Thats all there is. Notice that all we had to tell Java::Import about was java.rmi.Naming, this is because it was the only class we used by name in our Perl code, every other Java class (the objects held by $bean and $remote_interface) was returned by some other method call originating from java.rmi.Naming.

In order to run this example we have to make sure everything is in its place. We start by compiling the client code. Assuming that we have been given a Stub class file (RemoteObject_Stub.class) we can do the following:

gcj -C SomeBean.java RemoteInterface.java
fastjar -cvf client.jar SomeBean.class RemoteInterface.class RemoteObject_Stub.class

Making sure our server is reachable we can then run the client code:

CLASSPATH=client.jar perl client.pl

Thats it, you should then see the message returned by your server.

Claros Downloader is a simple, highly customizable, multi-threaded, web based downloader manager. You can download files to your desktop, corporate server, wherever you are. You simply point your browser to Claros Downloader, login, add new urls. It forks a new thread downloading the remote file to the server running the web application. Thats it.

Installation:

For Tomcat Users:

Copy the war file to $TOMCAT_INSTALL_DIR/webapps folder

Start Tomcat

For other application servers, you shall know what to do with a war file. If war extension means nothing to you, just unzip is it, if it was a regular zip archive.

All configuration is done in WEB-INF/resources directory. Open config.properties with your favorite editor, and follow the instructions.

Please Note: There is a Java class called AddUser.class in WEB-INF/classes/org/claros/downloader/admin directory. Run this class from console to add a new user to the system.

Asm2class is a java assembly to class file compiler.

Asm2class is release under the terms of the GPL License. The current version of asm2class (0.1.2) is a beta version and allow generating class file from java assembly file that contains class definition, field definition, method definition and constructor definition.

This release support also abstract class, abstract method and native method definition.

Asm2class know more thatn 90% of the java assembly language. Asm2class can do dead code detection, uninitialized register detection.