Minecraft Forums

Failed to connect to the server.

java.net.SocketException: Invalid argument

Quote from wreck »

I'm sure Notch will add support for the OS soon.

Quote from phobius »

I'm not sure if I should admit this - but I just got it working on tiger.

I bought the program after using it on my 2010 MacBook Pro (which runs it wonderfully) during the free weekend.

I tend not to carry the MBP with me (it's new, I'm paranoid), so after trying to show a friend on my (early) MacBook 1,1 (core duo 2, tiger 10.4.11, 2gb ram) and being gravely disappointed at this somewhat befuddling error (I'm not a java person) I succumbed to the old asberger's coder curiosity gene and had a poke around.

Turns out all you need to do is remove (replace?) the call to socket.setTrafficClass(24); in ii.class

I'm sure there are clever ways of fixing this, such as writing a class override - but here's what I did:

(dangerous admission follows, only select the text to view if you aren't going to sue me :smile.gif:)

1. looked at the system console, saw the traceback to setTrafficClass()
2. saw the source class (ii.class)
3. extracted the class files from ~/Library/Application Support/minecraft/bin/minecraft.jar using unzip (I don't know of a winrar equivalent in os x)
4. decompiled ii.class (jad)
5. commented out the line (line 28)
6. recompiled the class
7. added the new ii.class file to minecraft.jar using zip
8. ran minecraft, tried to join a server, got excited, began celebrating
9. got a java.lang.SecurityException: SHA1 digest error for ii.class exception
10. deleted the manifest from the .jar; zip -d minecraft.jar META-INF/MANIFEST.MF
11. ran minecraft
12. rejoiced


Again, I'm not a java person - all I've done here I've learnt by a bit of quick googling and head-scratching, but it works.

I'm well aware this could potentially be construed as disrespectful, but hopefully it's instead seen for what it is. I have no desire or intent to delve any further into the code or modify anything for fun/profit - I just wanted to be able to play this game :smile.gif:

that said - feel free to not make these changes (in fact I cannot condone following the above list), but hopefully they'll lead to Notch replacing this one line and suddenly having a lot of satisfied multiplayers that aren't ready (or able) to upgrade to Leopard or later.


oh and, hi! I'm new here. nice to meet you all.

jad ii.class

javac -classpath . ii.java

Parsing ii.class... Generating ii.java
Overlapped try statements detected. Not all exception handlers will be resolved
in the method a
Overlapped try statements detected. Not all exception handlers will be resolved
in the method b

C:\Program Files\Java\jdk1.6.0_21\bin>javac e:\temp\ii.java
e:\temp\ii.java:13: cannot find symbol
symbol  : class lb
location: class ii
    public ii(Socket socket, String s1, lb lb1)
                                        ^
e:\temp\ii.java:37: cannot find symbol
symbol  : class fn
location: class ii
    public void a(fn fn1)
                  ^
e:\temp\ii.java:199: cannot find symbol
symbol  : class lb
location: class ii
    private lb l;
            ^
e:\temp\ii.java:31: cannot find symbol
symbol  : class ni
location: class ii
        o = new ni(this, (new StringBuilder()).append(s1).append(" read thread")
.toString());
                ^
e:\temp\ii.java:32: cannot find symbol
symbol  : class nk
location: class ii
        n = new nk(this, (new StringBuilder()).append(s1).append(" write thread"
).toString());
                ^
e:\temp\ii.java:43: operator + cannot be applied to fn.a,int
            s += fn1.a() + 1;
                      ^
e:\temp\ii.java:43: inconvertible types
found   : <nulltype>
required: int
            s += fn1.a() + 1;
                         ^
e:\temp\ii.java:59: cannot find symbol
symbol  : class fn
location: class ii
                fn fn1;
                ^
e:\temp\ii.java:62: cannot find symbol
symbol  : class fn
location: class ii
                    fn1 = (fn)j.remove(0);
                           ^
e:\temp\ii.java:63: operator + cannot be applied to fn.a,int
                    s -= fn1.a() + 1;
                              ^
e:\temp\ii.java:63: operator - cannot be applied to int,<nulltype>
                    s -= fn1.a() + 1;
                      ^
e:\temp\ii.java:65: cannot find symbol
symbol  : variable fn
location: class ii
                fn.a(fn1, g);
                ^
e:\temp\ii.java:70: cannot find symbol
symbol  : class fn
location: class ii
                fn fn2;
                ^
e:\temp\ii.java:73: cannot find symbol
symbol  : class fn
location: class ii
                    fn2 = (fn)k.remove(0);
                           ^
e:\temp\ii.java:74: operator + cannot be applied to fn.a,int
                    s -= fn2.a() + 1;
                              ^
e:\temp\ii.java:74: operator - cannot be applied to int,<nulltype>
                    s -= fn2.a() + 1;
                      ^
e:\temp\ii.java:76: cannot find symbol
symbol  : variable fn
location: class ii
                fn.a(fn2, g);
                ^
e:\temp\ii.java:94: cannot find symbol
symbol  : class fn
location: class ii
            fn fn1 = fn.b(f);
            ^
e:\temp\ii.java:94: cannot find symbol
symbol  : variable fn
location: class ii
            fn fn1 = fn.b(f);
                     ^
e:\temp\ii.java:119: cannot find symbol
symbol  : class nh
location: class ii
        (new nh(this)).start();
             ^
e:\temp\ii.java:150: cannot find symbol
symbol  : class fn
location: class ii
        fn fn1;
        ^
e:\temp\ii.java:152: cannot find symbol
symbol  : class fn
location: class ii
            fn1 = (fn)i.remove(0);
                   ^
Note: e:\temp\ii.java uses unchecked or unsafe operations.
Note: Recompile with -Xlint:unchecked for details.
22 errors

Quote from Parkade »

Okay, so (I also tried this using the "manual" methods), but in dj decompiler (after extracting the contents of minecraft.jar), I open ii.class, comment out line 28, save it as a .java file, go to compile it to get the class file, then it says: (file location)ii.java:29: unreported exception java.IOException; must be caught or declared to be thrown f= new DataInputStream(socket.getInputStream()); then it says the same thing again, just replace the 29 with 30 and the f with g, and Inputstream with OutputStream.
I hope that helps, I'll try doing exactly what you just said immediately.

        socket.setTrafficClass(24);
        f = new DataInputStream(socket.getInputStream());
        g = new DataOutputStream(socket.getOutputStream());

        //socket.setTrafficClass(24);
        try {
			f = new DataInputStream(socket.getInputStream());
			g = new DataOutputStream(socket.getOutputStream());
		} catch (IOException ex) {
			a(ex);
		}

Quote from creonto »

i have this message but im a PC user so wtf?