J2EE Tutorial: Exception when building with ant

Question

I am trying to build the converter example on page 48 of the J2EE tutorial using ant. Ant seems to choke on the following line from the build.xml:
<property environment="myenv" />
The output of the "ant converter" command is:
Buildfile: build.xml
init:
BUILD FAILED
/usr/j2sdkee1.3/j2eetutorial/examples/src/build.xml:18: /usr/j2sdkee1.3/j2eetutorial/examples/src/build.xml:18: java.lang.StringIndexOutOfBoundsException: String index out of range: -1
--- Nested Exception ---
/usr/j2sdkee1.3/j2eetutorial/examples/src/build.xml:18: java.lang.StringIndexOutOfBoundsException: String index out of range: -1
--- Nested Exception ---
java.lang.StringIndexOutOfBoundsException: String index out of range: -1
at java.lang.String.substring(String.java:1525)
at org.apache.tools.ant.taskdefs.Property.loadEnvironment(Property.java:248)
at org.apache.tools.ant.taskdefs.Property.execute(Property.java:172)
at org.apache.tools.ant.Target.execute(Target.java:153)
at org.apache.tools.ant.Project.runTarget(Project.java:898)
at org.apache.tools.ant.Project.executeTarget(Project.java:536)
at org.apache.tools.ant.Project.executeTargets(Project.java:510)
at org.apache.tools.ant.Main.runBuild(Main.java:421)
at org.apache.tools.ant.Main.main(Main.java:149)
Total time: 1 second
My best guess is that the "myenv" line in the build.xml requires some additional attribute. I'm using ant version 1.3. My OS is Solaris (noted for possible environment-related issues).
Thanks in advance!
Eric Smith

Answer 1

On Windows XP Pro, the line
<property environment="myenv" />
in the init target of build.xml for the j2ee tutorial examples triggers a windows error message:
16 bit MS-DOS Subsystem
=======================
C:\WINDOWS\system32\ntvdm.exe
Error while setting up environment for the application. Choose 'Close' to terminate the application.
<<Close>> <<Ignore>>
So it looks as if ant is trying and failing to access the winnt system environment here.
According to Ant Developers Handbook (Sams, October 2002, chapter 4, p. 151), the ant environment property "specifies a prefix, giving access to OS-specific environment variables. This is not supported on all platforms." Until this problem is fixed, it appears that on XP systems anyway, any ant settings in build.xml files that rely on direct access to the system environment will fail. Here is some debug output from the j2ee tutorial examples init target which demonstrates this:
C:\apps\j2sdkee1.3.1\j2eetutorial\examples>ant init
Buildfile: build.xml
init:
[echo] starting init target
[echo] reached marker 1
[echo] reached marker 2
[echo] value of J2EE_HOME is ${myenv.J2EE_HOME}
[echo] finished init target
BUILD SUCCESSFUL
where the task:
<property environment="myenv" />
(which generates the OS error popup noted above) occurs between marker 1 and marker 2. Clearly the value of J2EE_HOME is NOT being successfully read from the system environment here.