INSTALL

JamVM 2.0.0 Installation
========================

This section describes how to configure, build and install JamVM on
your machine, along with the necessary class libraries.  For details
of the generic options to `configure' see the Basic Installation
section later in this file.

Getting the Files
-----------------

You must already have the compressed tar file containing the source
code for JamVM (you're reading this!).  For JamVM to run, it must also
have a class library containing the system classes and the associated
native methods (e.g. java.lang.Object).  JamVM 2.0.0 has been written to
work either OpenJDK/IcedTea or GNU Classpath.

OpenJDK/IcedTea
---------------

As discussed in the README, the easiest way to get an OpenJDK/IcedTea
install that works with JamVM is to get an existing package for your
system and then overwrite the libjvm.so file with the new version.  If you
wish to build OpenJDK/IcedTea from source, please refer to the build
instructions contained within the source distribution.

GNU Classpath
-------------

JamVM is compatible with GNU Classpath versions 0.98 and above (earlier
versions will not work).  It should also be compatible with the CVS version.

Classpath can be obtained from the following URL:

ftp://ftp.gnu.org/gnu/classpath

The class library consists of the Java classes and the shared libraries
containing the native methods.  As GNU Classpath uses generics, a Java 1.5
compatible compiler is required to build the classes, e.g. the Eclipse
Java Compiler (ecj).  This is available as a standalone package in most
Linux distributions.


Building and Installing JamVM
-----------------------------

To build JamVM, you must first run `configure' to generate the Makefiles
specific to your machine.  The --with-java-runtime-library option specifies
which class-library to support (by default if the option isn't specified
JamVM is configured for GNU Classpath).  Supported values are gnuclasspath,
openjdk6, openjdk7 or openjdk8.

For example, to configure JamVM to use OpenJDK 8, from the directory
containing this file do :-

./configure --with-java-runtime-library=openjdk8

This should print out some information and then say it's creating
the Makefiles.  If it fails, make sure your machine's architecture
is supported by JamVM.

Then, to build JamVM, type :-

make

To install in the default location (/usr/local), type :-

make install

This installs an executable of JamVM and a libjvm.so shared library with
debug information (-g).  Alternatively, to install a version with no symbols
(which is much smaller) type :-

make install-strip

Note, you must be root to install in the default location.


configure options
-----------------

JamVM by default installs in /usr/local/jamvm.  You can change the
installation directory by giving configure the option :-

--prefix=PATH

JamVM supports a number of JamVM specific options to `configure'.
For full details do ./configure --help.  Most of these are concerned
with enabling tracing (e.g. --enable-tracelock), or selecting which
interpreter variant to build.  Unless you want to debug JamVM, or
experiment with the interpreter these should not be needed.

Two options, however, are useful and may need to be specified.  The
first is '--with-classpath-install-dir=PATH'.  This can be used to
specify the base directory in which the GNU classpath class and
shared libraries are to be found.  By default this is taken to be
/usr/local/classpath, GNU classpath's default install location.
However, if you install GNU classpath in another place, this MUST
be given using this option.  It should be set to the same value as
you gave to --prefix when configuring Classpath.

The second is  '--disable-zip'.  This disables support for zip/jar files
in the bootstrap class loader (the application class loader is Java-based,
via Classpath and is unaffected, and will still support jar/zip files).
This will reduce the JamVM executable by approx 10K (but see note below, in
Classpath installation).

Installing JamVM into OpenJDK/IcedTea
-------------------------------------

When using JamVM with OpenJDK/IcedTea, JamVM's libjvm.so file must be
copied from its initial install location into the OpenJDK/IcedTea
installation.

The default install location puts libjvm.so into /usr/local/jamvm/lib.

IcedTea supports JamVM as an alternative VM which is invoked using the
-jamvm option to java.  To install a new version of libjvm.so, locate the
jamvm directory within IcedTea.  For example, for OpenJDK 7 on an x64_64
Debian system this is /usr/lib/jvm/java-7-openjdk-amd64/jre/lib/amd64/jamvm.

If installing into OpenJDK, the default HotSpot libjvm.so can be overwritten
by JamVM's libjvm.so.  When java is executed it will now run JamVM (if
HotSpot is still required you can create a copy of OpenJDK, and overwrite
the libjvm.so in the copy).  HotSpot will be in either the client or server
directory, e.g. <openjdk-install>/jre/lib/amd64/server.

Do the copy (as root), e.g.:

cp /usr/local/jamvm/lib/libjvm.so /usr/lib/jvm/java-7-openjdk-amd64/jre/lib/amd64/jamvm

To test the install has been successful, run java -version, e.g.:

/usr/lib/jvm/java-7-openjdk-amd64/jre/bin/java -jamvm -version
java version "1.7.0_65"
OpenJDK Runtime Environment (IcedTea 2.5.1) (7u65-2.5.1-2~deb7u1)
JamVM (build 2.0.0, inline-threaded interpreter)


Building and Installing GNU classpath
-------------------------------------

This section gives basic instructions for building and installing
GNU Classpath using ecj.  For full information on Classpath options
see the INSTALL file inside the GNU Classpath directory.

1) Run `configure' - cd into the unpacked GNU Classpath directory
   and type :-

./configure
 
Note, this builds the AWT "peer" classes, the gconf peer classes and
gcjwebplugin.  If configure fails, refer to the Classpath INSTALL file
to make sure you have what's needed.  Alternatively, adding
`--disable-gtk-peer --disable-gconf-peer --disable-plugin' will turn off
their compilation, but you'll be unable to use or test any GUI applications.

2) Build GNU Classpath by typing :-

make

3) Then, to install GNU Classpath in the default location
   (/usr/local/classpath), type :-

make install

As with installing JamVM, you may need to be root to install the files.


That's it!  As long as you have /usr/local/jamvm/bin in your path, you should
now be able to run JamVM by typing `jamvm'.

------
Note: If you configured JamVM to disable zip support in the bootstrap
class loader you will need to unzip Classpath's class files, which are
by default contained within a .zip file.

cd to the classpath installation directory.  The .zip file is located at:

<classpath prefix>/classpath/share/classpath/glibj.zip

for the default installation location this is:

/usr/local/classpath/share/classpath/glibj.zip

unzip glibj.zip


Basic Installation
==================

   These are generic installation instructions.

   The `configure' shell script attempts to guess correct values for
various system-dependent variables used during compilation.  It uses
those values to create a `Makefile' in each directory of the package.
It may also create one or more `.h' files containing system-dependent
definitions.  Finally, it creates a shell script `config.status' that
you can run in the future to recreate the current configuration, a file
`config.cache' that saves the results of its tests to speed up
reconfiguring, and a file `config.log' containing compiler output
(useful mainly for debugging `configure').

   If you need to do unusual things to compile the package, please try
to figure out how `configure' could check whether to do them, and mail
diffs or instructions to the address given in the `README' so they can
be considered for the next release.  If at some point `config.cache'
contains results you don't want to keep, you may remove or edit it.

   The file `configure.in' is used to create `configure' by a program
called `autoconf'.  You only need `configure.in' if you want to change
it or regenerate `configure' using a newer version of `autoconf'.

The simplest way to compile this package is:

  1. `cd' to the directory containing the package's source code and type
     `./configure' to configure the package for your system.  If you're
     using `csh' on an old version of System V, you might need to type
     `sh ./configure' instead to prevent `csh' from trying to execute
     `configure' itself.

     Running `configure' takes awhile.  While running, it prints some
     messages telling which features it is checking for.

  2. Type `make' to compile the package.

  3. Optionally, type `make check' to run any self-tests that come with
     the package.

  4. Type `make install' to install the programs and any data files and
     documentation.

  5. You can remove the program binaries and object files from the
     source code directory by typing `make clean'.  To also remove the
     files that `configure' created (so you can compile the package for
     a different kind of computer), type `make distclean'.  There is
     also a `make maintainer-clean' target, but that is intended mainly
     for the package's developers.  If you use it, you may have to get
     all sorts of other programs in order to regenerate files that came
     with the distribution.

Compilers and Options
=====================

   Some systems require unusual options for compilation or linking that
the `configure' script does not know about.  You can give `configure'
initial values for variables by setting them in the environment.  Using
a Bourne-compatible shell, you can do that on the command line like
this:
     CC=c89 CFLAGS=-O2 LIBS=-lposix ./configure

Or on systems that have the `env' program, you can do it like this:
     env CPPFLAGS=-I/usr/local/include LDFLAGS=-s ./configure

Compiling For Multiple Architectures
====================================

   You can compile the package for more than one kind of computer at the
same time, by placing the object files for each architecture in their
own directory.  To do this, you must use a version of `make' that
supports the `VPATH' variable, such as GNU `make'.  `cd' to the
directory where you want the object files and executables to go and run
the `configure' script.  `configure' automatically checks for the
source code in the directory that `configure' is in and in `..'.

   If you have to use a `make' that does not supports the `VPATH'
variable, you have to compile the package for one architecture at a time
in the source code directory.  After you have installed the package for
one architecture, use `make distclean' before reconfiguring for another
architecture.

Installation Names
==================

   By default, `make install' will install the package's files in
`/usr/local/bin', `/usr/local/man', etc.  You can specify an
installation prefix other than `/usr/local' by giving `configure' the
option `--prefix=PATH'.

   You can specify separate installation prefixes for
architecture-specific files and architecture-independent files.  If you
give `configure' the option `--exec-prefix=PATH', the package will use
PATH as the prefix for installing programs and libraries.
Documentation and other data files will still use the regular prefix.

   In addition, if you use an unusual directory layout you can give
options like `--bindir=PATH' to specify different values for particular
kinds of files.  Run `configure --help' for a list of the directories
you can set and what kinds of files go in them.

   If the package supports it, you can cause programs to be installed
with an extra prefix or suffix on their names by giving `configure' the
option `--program-prefix=PREFIX' or `--program-suffix=SUFFIX'.

Optional Features
=================

   Some packages pay attention to `--enable-FEATURE' options to
`configure', where FEATURE indicates an optional part of the package.
They may also pay attention to `--with-PACKAGE' options, where PACKAGE
is something like `gnu-as' or `x' (for the X Window System).  The
`README' should mention any `--enable-' and `--with-' options that the
package recognizes.

   For packages that use the X Window System, `configure' can usually
find the X include and library files automatically, but if it doesn't,
you can use the `configure' options `--x-includes=DIR' and
`--x-libraries=DIR' to specify their locations.

Specifying the System Type
==========================

   There may be some features `configure' can not figure out
automatically, but needs to determine by the type of host the package
will run on.  Usually `configure' can figure that out, but if it prints
a message saying it can not guess the host type, give it the
`--host=TYPE' option.  TYPE can either be a short name for the system
type, such as `sun4', or a canonical name with three fields:
     CPU-COMPANY-SYSTEM

See the file `config.sub' for the possible values of each field.  If
`config.sub' isn't included in this package, then this package doesn't
need to know the host type.

   If you are building compiler tools for cross-compiling, you can also
use the `--target=TYPE' option to select the type of system they will
produce code for and the `--build=TYPE' option to select the type of
system on which you are compiling the package.

Sharing Defaults
================

   If you want to set default values for `configure' scripts to share,
you can create a site shell script called `config.site' that gives
default values for variables like `CC', `cache_file', and `prefix'.
`configure' looks for `PREFIX/share/config.site' if it exists, then
`PREFIX/etc/config.site' if it exists.  Or, you can set the
`CONFIG_SITE' environment variable to the location of the site script.
A warning: not all `configure' scripts look for a site script.

Operation Controls
==================

   `configure' recognizes the following options to control how it
operates.

`--cache-file=FILE'
     Use and save the results of the tests in FILE instead of
     `./config.cache'.  Set FILE to `/dev/null' to disable caching, for
     debugging `configure'.

`--help'
     Print a summary of the options to `configure', and exit.

`--quiet'
`--silent'
`-q'
     Do not print messages saying which checks are being made.  To
     suppress all normal output, redirect it to `/dev/null' (any error
     messages will still be shown).

`--srcdir=DIR'
     Look for the package's source code in directory DIR.  Usually
     `configure' can determine that directory automatically.

`--version'
     Print the version of Autoconf used to generate the `configure'
     script, and exit.

`configure' also accepts some other, not widely useful, options.