Communication between C++ app and Java
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Hi, i need a way to communicate between my app which is written in C++ and Java. The problem is, the application that runs the java code is not mine and it just runs the java code in a safe environment. This poses some security restrictions such as, i can't open any sockets, and seeings that was the obvious way to me to make them communicate, i don't know what to try next. Are there any facilities in Java to make communication with another windows application easier? Thanks in advance for any responses. Kuniva --------------------------------------------
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Hi, i need a way to communicate between my app which is written in C++ and Java. The problem is, the application that runs the java code is not mine and it just runs the java code in a safe environment. This poses some security restrictions such as, i can't open any sockets, and seeings that was the obvious way to me to make them communicate, i don't know what to try next. Are there any facilities in Java to make communication with another windows application easier? Thanks in advance for any responses. Kuniva --------------------------------------------
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Hi, i need a way to communicate between my app which is written in C++ and Java. The problem is, the application that runs the java code is not mine and it just runs the java code in a safe environment. This poses some security restrictions such as, i can't open any sockets, and seeings that was the obvious way to me to make them communicate, i don't know what to try next. Are there any facilities in Java to make communication with another windows application easier? Thanks in advance for any responses. Kuniva --------------------------------------------
I'm going to pretend to be an expert on this because I just hooked up a browser-based Java application to a complex C++ library using JNI. To get meaningful communication between the Java applet and your C++ application, you are probably going to need to remove the security restrictions on the applet so it runs outside the browser's sandbox. You can do this by signing the applet with a cryptographic signature, or by running the Java code as an application instead of an applet. Once you do this, the Java app and your C++ app can communicate by sockets, or writing files to the local filesystem, or you could use JNI (or COM if the applet is written for the Microsoft VM) and package your C++ app as a DLL that the Java applet can call. If you can't or don't want to change the security restrictions on the Java applet, pretty much the only way to get it to communicate is to have both it and your C++ app talk to the same server on the applet's host (I suppose you could also send Windows messages to the applet's window, but that's a really limited form of communication). Applets are allowed to open a socket, but only back to a server on the host from which they were downloaded. Hosting the applet on your local machine might work for you as well.
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What do you exactely want to do upon the java application? Wouldn't signal sends work ?
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I'm going to pretend to be an expert on this because I just hooked up a browser-based Java application to a complex C++ library using JNI. To get meaningful communication between the Java applet and your C++ application, you are probably going to need to remove the security restrictions on the applet so it runs outside the browser's sandbox. You can do this by signing the applet with a cryptographic signature, or by running the Java code as an application instead of an applet. Once you do this, the Java app and your C++ app can communicate by sockets, or writing files to the local filesystem, or you could use JNI (or COM if the applet is written for the Microsoft VM) and package your C++ app as a DLL that the Java applet can call. If you can't or don't want to change the security restrictions on the Java applet, pretty much the only way to get it to communicate is to have both it and your C++ app talk to the same server on the applet's host (I suppose you could also send Windows messages to the applet's window, but that's a really limited form of communication). Applets are allowed to open a socket, but only back to a server on the host from which they were downloaded. Hosting the applet on your local machine might work for you as well.
Well the problem is that the java code is not running in a browser and its not an applet, its just.. scripts running through JNI already by another application, so i can write the scripts, but not change the application. So i want to communicate with the scripts. Kuniva --------------------------------------------
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Well the problem is that the java code is not running in a browser and its not an applet, its just.. scripts running through JNI already by another application, so i can write the scripts, but not change the application. So i want to communicate with the scripts. Kuniva --------------------------------------------
If code you don't control is putting the Java code in a restricted sandbox, there isn't a lot you can do (that's what the sandbox features is for, after all). Do you know the details of the sandbox restrictions? Do you get a SecurityException when you try to connect to a local socket from the Java?
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If code you don't control is putting the Java code in a restricted sandbox, there isn't a lot you can do (that's what the sandbox features is for, after all). Do you know the details of the sandbox restrictions? Do you get a SecurityException when you try to connect to a local socket from the Java?
Yes thats exactly how it is. But when i try to make a socket, i just get an error, not an exception i think, the code is basically like this:
try { ds = new Socket(InetAddress.getByName("localhost"),port); } catch(UnknownHostException uhe) {} catch(IOException ie) {} catch(Error e) { CodexConsole.Print(0,1,"Error"); }And i always get the error. I looked at the definition of JNI_CreateJavaVM and there's like three parameters u pass right? Well i might be able to "crack" them out of the java container application if i know what to change, but i'm not sure.. Would that work? if i could somehow lift the restrictions? Thanks for your help. Kuniva --------------------------------------------
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Yes thats exactly how it is. But when i try to make a socket, i just get an error, not an exception i think, the code is basically like this:
try { ds = new Socket(InetAddress.getByName("localhost"),port); } catch(UnknownHostException uhe) {} catch(IOException ie) {} catch(Error e) { CodexConsole.Print(0,1,"Error"); }And i always get the error. I looked at the definition of JNI_CreateJavaVM and there's like three parameters u pass right? Well i might be able to "crack" them out of the java container application if i know what to change, but i'm not sure.. Would that work? if i could somehow lift the restrictions? Thanks for your help. Kuniva --------------------------------------------