RFR: 8336382: Fixes error reporting in loading AWT and fonts [v4]

Sat Sep 28 23:03:56 UTC 2024

> If there is a problem with finding and calling e.g. `java/awt/GraphicsEnvironment` in `AWTIsHeadless`, the env' Exception remains set and it is not cleared. Later, that manifests as:
> 
>     Fatal error reported via JNI: Could not allocate library name
> 
> Which is misleading. The code path is perhaps rare in a normal JDK usage, but it has been complicating our users' bug reports in the GraalVM/native-image ecosystem for quite some time.
> 
> Instead of failing later indicating that the user has incorrectly configured JNI, it bails out very soon with a message that seems as if a jstring could not have been allocated. It sends users on wild goose chases where it appears `JNU_NewStringPlatform` calls failed,  e.g.
> 
> * https://github.com/oracle/graal/issues/9138
> * https://github.com/oracle/graal/issues/8475
> * https://github.com/oracle/graal/issues/9300
> * https://github.com/quarkusio/quarkus/issues/31596
> * https://github.com/graalvm/mandrel/issues/292
> * https://github.com/Karm/mandrel-integration-tests/issues/262
> 
> This commit fixes the error reporting in the AWTIsHeadless.
> 
> Furthermore, when AOT compiled, there is little sense for having a JAVA_HOME, yet some parts of AWT code look for it to search fonts. In such case, an empty directory structure is enough to accommodate it, e.g.
> 
> /tmp/JAVA_HOME/
> /tmp/JAVA_HOME/conf
> /tmp/JAVA_HOME/conf/fonts
> /tmp/JAVA_HOME/lib
> 
> The exception is somewhat cryptic for users again, merely stating:
> 
>     Exception in thread "main" java.io.IOException: Problem reading font data.
>         at java.desktop at 22.0.1/java.awt.Font.createFont0(Font.java:1205)
>         at java.desktop at 22.0.1/java.awt.Font.createFont(Font.java:1076)
>         at imageio.Main.loadFonts(Main.java:139
> 
> Adding the cause there makes it clearer, i.e. that JAVA_HOME might be missing:
> 
>     Exception in thread "main" java.io.IOException: Problem reading font data.
>         at java.desktop at 23-internal/java.awt.Font.createFont0(Font.java:1206)
>         at java.desktop at 23-internal/java.awt.Font.createFont(Font.java:1076)
>         at imageio.Main.loadFonts(Main.java:139)
>         at imageio.Main.paintRectangles(Main.java:97)
>         at imageio.Main.main(Main.java:195)
>         at java.base at 23-internal/java.lang.invoke.LambdaForm$DMH/sa346b79c.invokeStaticInit(LambdaForm$DMH)
>     Caused by: java.lang.Error: java.home property not set
>         at java.desktop at 23-internal/sun.awt.FontConfiguration.findFontConfigFile(FontConfiguration.java:180)
>         at java.desktop at 23-internal/sun.awt.FontConf...

Karm Michal Babacek has updated the pull request with a new target base due to a merge or a rebase. The incremental webrev excludes the unrelated changes brought in by the merge/rebase. The pull request contains five additional commits since the last revision:

 - Merge branch 'master' of github.com:openjdk/jdk into awt-load-messages-fonts_backup
 - Display "Problem reading font data. java.home property not set." when java.homenot set and AWT cannot try to lookup fonts
 - Treats missing class as a fatal error
 - Reverts changes to java/awt/Font.java
 - Fixes error reporting in loading AWT and fonts

   If there is problem with finding and calling e.g. java/awt/GraphicsEnvironment
   in AWTIsHeadless, the env' Exception remains set and it not cleared.
   Later, that manifests as:

       Fatal error reported via JNI: Could not allocate library name

   Which is misleading. The code path is perhaps rare in normal JDK usage,
   but it has been complicating our users' bug reports in the GraalVM/native-image
   ecosystem for quite some time.

   Instead of failing later with some clear message that indicates that the
   user has incorrectly configured JNI, it bails out very soon with a message
   that seems as if a jstring could not have been allocated. It sends users
   on wild goose chases, e.g.

   https://github.com/oracle/graal/issues/9138
   https://github.com/oracle/graal/issues/8475
   https://github.com/oracle/graal/issues/9300
   https://github.com/quarkusio/quarkus/issues/31596
   https://github.com/graalvm/mandrel/issues/292
   https://github.com/Karm/mandrel-integration-tests/issues/262

   This commit fixes the error reporting in the AWTIsHeadless.

   Furthermore, when AOT compiled, there is little sense for having a JAVA_HOME,
   yet some parts of AWT code look for it to search fonts. In such case, an
   empty directory structure is enough to accommodate it, e.g.

   /tmp/JAVA_HOME/
   /tmp/JAVA_HOME/conf
   /tmp/JAVA_HOME/conf/fonts
   /tmp/JAVA_HOME/lib

   The exception is somewhat cryptic for users again, merely stating:

       Exception in thread "main" java.io.IOException: Problem reading font data.
           at java.desktop at 22.0.1/java.awt.Font.createFont0(Font.java:1205)
           at java.desktop at 22.0.1/java.awt.Font.createFont(Font.java:1076)
           at imageio.Main.loadFonts(Main.java:139

   Adding the cause there makes it clearer, i.e. that JAVA_HOME might be missing:

       Exception in thread "main" java.io.IOException: Problem reading font data.
           at java.desktop at 23-internal/java.awt.Font.createFont0(Font.java:1206)
           at java.desktop at 23-internal/java.awt.Font.createFont(Font.java:1076)
           at imageio.Main.loadFonts(Main.java:139)
           at imageio.Main.paintRectangles(Main.java:97)
           at imageio.Main.main(Main.java:195)
           at java.base at 23-internal/java.lang.invoke.LambdaForm$DMH/sa346b79c.invokeStaticInit(LambdaForm$DMH)
       Caused by: java.lang.Error: java.home property not set
           at java.desktop at 23-internal/sun.awt.FontConfiguration.findFontConfigFile(FontConfiguration.java:180)
           at java.desktop at 23-internal/sun.awt.FontConfiguration.<init>(FontConfiguration.java:97)

-------------

Changes:
  - all: https://git.openjdk.org/jdk/pull/20169/files
  - new: https://git.openjdk.org/jdk/pull/20169/files/4e33725a..8b203e7c

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jdk&pr=20169&range=03
 - incr: https://webrevs.openjdk.org/?repo=jdk&pr=20169&range=02-03

  Stats: 256790 lines in 3090 files changed: 209022 ins; 30625 del; 17143 mod
  Patch: https://git.openjdk.org/jdk/pull/20169.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/20169/head:pull/20169

PR: https://git.openjdk.org/jdk/pull/20169