MacOsJavaHelp

Introduction

MacOS 10.6, Snow Leopard, runs Java 1.6 by default. This document explains how to install Java 1.5

Quick and dirty

The fastest and simplest solution is this one, however, this requires installing Java from a potentially untrusted source. If you feel uneasy about this, please go on to the next solution.

Safe, but complicated

(The solution below was contributed by Thomas Parsli.)

Prerequisites

1. Java 1.5 Update 4 (or later) from Apple
2. Pacifist or any other application which can open .dmg and .pkg files

Howto

1. Remove the symlinks 1.5 and 1.5.0 from /System/Library/Frameworks/JavaVM.framework/Versions/
2. Start Pacifist and open JavaForMacOSX10.5Update4.dmg
3. Browse the pkg-file (JavaForMacOSX10.5Update4.pkg) and navigate to "JavaForMacOSX10.5Update4.pkg -> Contents > System > Library > Frameworks > JavaVM.framework > Versions"
4. Select (hold shift and click) 1.5 and 1.5.0, then right click and choose "Install to Default Location"

Optional steps to prevent Apples "Software Update" from removing the installed java-1.5 versions

1. Navigate to /System/Library/Frameworks/JavaVM.framework/Versions/
2. Move/rename 1.5.0 to the complete java version. For the "10.5 Update 4" release, this is 1.5.0_19
3. Create symlinks from 1.5.0_19 to 1.5.0 and 1.5

The next time "Software Update" updates java, it will probably remove your links and create new ones pointing to CurrentJDK. You'll then have to recrate the 1.5 and 1.5.0 symlinks.

Running Java 1.5 on OS X Snow Leopard

Running the correct Java version and setting heap-size

export JAVA_HOME=/System/Library/Frameworks/JavaVM.framework/Versions/1.5/Home/
alias java="$JAVA_HOME/bin/java -Xmx200M $@"