Hi Jordan Fix,
Nashorn generated code is not usable by re-loading from a .class file. A
static field by the name "constants" is set after generating, loading
bytecode generated for a script. The "constants" array contains both
serializable and non-serializable items (such as PropertyMap). Code
generator generates bytecode and associated constants array together -
installs code with CodeInstaller object (passed from Context) and sets
the "constants" array.
Unless you figure out a way to serialize constants array (say you may
skip PropertyMaps - but put enough information to reconstruct those and
so on) and deserialize to set constants field after loading bits from a
.class file/byte array, "precompiled" scheme won't work.
-Sundar
On Monday 29 July 2013 09:31 AM, Jordan Fix wrote:
Hello,
I've been attempting to modify the nashorn shell so that you can specify a byte
code file to load in and execute instead of having to do the compilation prior
to execution every time. This allows hand modification of byte code for
example. I've hit an issue which I don't know how to get past, hoping someone
can give me a tip.
To get started I've passed the compile only and dump flags to the shell to get the byte
code for a simple hello world JS file, and have been hackily trying to get this to work
with a new "precompiled" flag. I load in the byte code file, and tried to
follow a similar flow to when it is compiled at runtime without going through the
compilation phases -- I just add the byte code to the compiler and then call install on
it with the byte code and file name.
I am currently getting the following exception:
Exception in thread "main" java.lang.ArrayIndexOutOfBoundsException: 0
at jdk.nashorn.internal.scripts.Script$test.$getMap(test.js)
at jdk.nashorn.internal.scripts.Script$test.runScript(test.js)
at
jdk.nashorn.internal.runtime.ScriptFunctionData.invoke(ScriptFunctionData.java:520)
at
jdk.nashorn.internal.runtime.ScriptFunction.invoke(ScriptFunction.java:203)
at
jdk.nashorn.internal.runtime.ScriptRuntime.apply(ScriptRuntime.java:366)
at jdk.nashorn.tools.Shell.apply(Shell.java:619)
at jdk.nashorn.tools.Shell.runScripts(Shell.java:529)
at jdk.nashorn.tools.Shell.run(Shell.java:296)
at jdk.nashorn.tools.Shell.main(Shell.java:154)
at jdk.nashorn.tools.Shell.main(Shell.java:133)
I'm guessing this has something to do with the execution environment not being
set up correctly, as there is an empty array being loaded from.
Thanks for any assistance you can give me.
Jordan Fix
