Java example source code file (README)

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copyright, ctw, foundation, free, general, gnu, license, oracle, public, software, this, without, xx:+unlockdiagnosticvmoptions, xx:+whiteboxapi

The README Java example source code

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DESCRIPTION

This is replacement for CompileTheWorld (CTW) written on java. Its purpose is
to make possible the use of CTW in product builds.

DEPENDENCES

The tool depends on Whitebox API. Assumed, that the sources of whitebox are
located in '../whitebox' directory.

BUILDING

Simple way to build, just type 'make'.

Makefile uses environment variables 'ALT_BOOTDIR', 'BOOTDIR' as root-dir of jdk
that will be used for compilation and creating jar.

On successful building 'ctw.jar' will be created.

RUNNING

Since the tool uses WhiteBox API, options 'UnlockDiagnosticVMOptions' and
'WhiteBoxAPI' should be specified, and 'wb.jar' should be added to
boot-classpath:
  $ java -XX:+UnlockDiagnosticVMOptions -XX:+WhiteBoxAPI -Xbootclasspath/a:wb.jar -jar ctw.jar 

Arguments can be paths to '.jar, '.zip', '.lst' files or directories with
classes, that define which classes will be compiled:
  - '.jar', '.zip' files and directories are interpreted like in classpath
(including '<dir>/*' syntax)
  - '.lst' files -- files with class names (in java notation) to compile.
CTW will try to find these classes with default class loader, so they should
be located in classpath.

Without arguments it would work as old version of CTW: all classes in
boot-classpath will be compiled, excluding classes in 'rt.jar' if 'rt.jar' isn't
first in boot-classpath.

Due CTW's flags also are not available in product builds, the tool uses
properties with the same names:
  - 'CompileTheWorldPreloadClasses' -- type:boolean, default:true, description:
Preload all classes used by a class before start loading
  - 'CompileTheWorldStartAt' -- type:long, default:1, description: First class
to consider
  - 'CompileTheWorldStopAt' -- type:long, default:Long.MAX_VALUE, description:
Last class to consider

Also it uses additional properties:
  - 'sun.hotspot.tools.ctw.verbose' -- type:boolean, default:false,
description: Verbose output, adds additional information about compilation
  - 'sun.hotspot.tools.ctw.logfile' -- type:string, default:null,
description: Path to logfile, if it's null, cout will be used.

EXAMPLES

compile classes from 'rt.jar':
  $ java -XX:+UnlockDiagnosticVMOptions -XX:+WhiteBoxAPI -Xbootclasspath/a:wb.jar -jar ctw.jar ${JAVA_HOME}/jre/lib/rt.jar

compile classes from all '.jar' in './testjars' directory:
  $ java -XX:+UnlockDiagnosticVMOptions -XX:+WhiteBoxAPI -Xbootclasspath/a:wb.jar -jar ctw.jar ./testjars/*

compile classes from './build/classes' directory:
  $ java -XX:+UnlockDiagnosticVMOptions -XX:+WhiteBoxAPI -Xbootclasspath/a:wb.jar -jar ctw.jar ./build/classes

compile only java.lang.String, java.lang.Object classes:
  $ echo java.lang.String > classes.lst
  $ echo java.lang.Object >> classes.lst
  $ java -XX:+UnlockDiagnosticVMOptions -XX:+WhiteBoxAPI -Xbootclasspath/a:wb.jar -jar ctw.jar classes.lst