JDK and JRE 1.5

[sammy1]

It seems jre 1.5 breaks most of my applications
built with a previous jdk (1.4 say). Is there an
overall reason for this? Something like tools.jar
is no longer there or similar or is it some programming
reason (to do with generics for example).
It seems as bad as MS .NET for breaking stuff.
Lucy1

 

[Ian Mills]

It seems jre 1.5 breaks most of my applications
built with a previous jdk (1.4 say). Is there an
overall reason for this? Something like tools.jar
is no longer there or similar or is it some programming
reason (to do with generics for example).
It seems as bad as MS .NET for breaking stuff.
Lucy1

what exactly are the problems you are experiencing. Just saying it
breaks your applications makes it a little difficult to comment on.

 

[plmBond007]

Atlease I know 1 programmatic change in 1.5
that enum is now keyword in jdk1.5
and if you have used it as variable, that could be a problem..

-Himanshu

 

[Ranganath Kini]

Generics cannot break compatibility. The very design of generics in JDK
1.5 ensures that it maintains 100% compatibility with classic code. At
the most you might be displayed a warning if you try to recompile your
old non-generics enabled code with the 1.5 Java compiler.

Please give use some code or quote some error messages about your
problem so that we can try to suggest some remedy to your issue.

 

[Roedy Green]

It seems jre 1.5 breaks most of my applications
built with a previous jdk (1.4 say). Is there an
overall reason for this? Something like tools.jar
is no longer there or similar or is it some programming
reason (to do with generics for example).
It seems as bad as MS .NET for breaking stuff.

you mean your code stops working or you just get a lot of generics
warning messages?

 

[billreyn]

I tried it on our application server, and the jsp pages
would not compile (they compile automatically usually)
but throw massive errors with jre 1.5.
Maybe I am doing sthg silly and its actually OK, but my
application server will only work with JSP 1.2, not
JSP 2, or...do I simply need the jdk and not the jre?
I am using the jre in Program Files/java - its full of
automatic jre downloads.
I would be so pleased if it did work with 1.5 (at present
we use 1.4)
Lucy1

 

[John C. Bollinger]

I tried it on our application server, and the jsp pages
would not compile (they compile automatically usually)
but throw massive errors with jre 1.5.
Maybe I am doing sthg silly and its actually OK, but my
application server will only work with JSP 1.2, not
JSP 2, or...do I simply need the jdk and not the jre?
I am using the jre in Program Files/java - its full of
automatic jre downloads.
I would be so pleased if it did work with 1.5 (at present
we use 1.4)

Wait a minute -- what exactly did you try? Did you write JSP pages
containing scriptlets that make use of Java 1.5 features, and attempt to
compile them on your existing app server? That's bound to fail unless
you ensure that your app server is compiling the pages with a Java 1.5
compiler. The JRE does not contain a Java source -> bytecode compiler,
which JSP page compilation requires.

Any way, we're shooting in the dark. For better-targeted help, post the
first few error messages that you receive, and provide as much detail as
you can about the environment (application server and version, Java
configuration, whatever else may be relevant) and about the code you are
using.

 

[billreyn]

I simply changed the jre in the properties file of the
app server and it would not compile any jsp page
at all. But maybe, it simply cannot find the javac
(which is not in the windows jre auto download)
I'll do some more tests with a proper jdk 1.5
instead of jre 1.5.

 

[Thomas Kellerer]

I simply changed the jre in the properties file of the
app server and it would not compile any jsp page
at all. But maybe, it simply cannot find the javac
(which is not in the windows jre auto download)
I'll do some more tests with a proper jdk 1.5
instead of jre 1.5.

Which app server are you using? Tomcat does need a JDK it does *not*
work with a JRE

Thomas

 

[billreyn]

I downloaded jdk1.5.0_02 and installed it. Even
on a simple java class run its gives the error:

Error occurred during initialization of VM
java/lang/NoClassDefFoundError: java/lang/Object

But JDK 1.5.0 is OK in the tests I have done so far
anyway (although I am worried by 4 page not found
errors on my App Server - ie servlets not found!)


So, either my download of jdk1.5.0_02 was corrupted
or there's a fault in it somewhere, (in my opinion).