I have created a simple test case to test Java 9 Web Start with the new modules. Unfortunately, Java 9 Web Start does not by default support --permit-illegal-access like regular Java 9 does.
Java 9 Web Start is suppose to support --add-opens (see https://bugs.openjdk.java.net/browse/JDK-8172986).
I'm using Java 1.9.0_181_ea.
Here is my test class:
import java.awt.Toolkit;
import java.lang.reflect.Method;
import java.lang.IllegalAccessException;
import java.lang.reflect.InvocationTargetException;
public class Java9BreaksWhenTest {
public static void main(String args[]) throws IllegalAccessException, InvocationTargetException {
System.out.println("Hello World");
// Do some dangerous reflection
Toolkit toolkit = Toolkit.getDefaultToolkit();
Class c = toolkit.getClass();
while(true) {
Method m = null;
try {
m = c.getDeclaredMethod("setDesktopProperty", String.class, Object.class);
} catch (NoSuchMethodException ex) {
c = c.getSuperclass();
if (c!=null)
continue;
} catch (SecurityException ex) {
ex.printStackTrace();
}
if (m!=null) {
m.setAccessible(true);
m.invoke(toolkit, "awt.font.desktophints", null);
System.out.println("desktop Properties changed.");
}
break;
}
}
}
Here is my JNLP file which should make java.awt code able to accessible.
<?xml version="1.0" encoding="UTF-8"?>
<jnlp spec="1.0+" codebase="file:///home/smm/hcs/testcode" href="java9BreaksWhenTest.jnlp">
<information>
<title>Java 9 Breaks When Test</title>
<vendor>HCS</vendor>
<homepage href="http://hcs.us.com"/>
<description>Java 9 Breaks When Test</description>
<description kind="short">Java 9 Breaks When Test</description>
</information>
<security><all-permissions/></security>
<update check="timeout" policy="always"/>
<resources>
<j2se version="9" java-vm-args="--add-opens java.desktop/java.awt=ALL-UNNAMED" />
<jar href="Java9BreaksWhenTest.jar" main="true" download="eager"/>
</resources>
<application-desc main-class="Java9BreaksWhenTest">
</application-desc>
</jnlp>
This seems inline with what is discussed here (How to pass the Java 9 '--permit-illegal-access' flag to a Webstart application?). However, it does not work. Running it under Java Web Start I get the following error:
Hello World
java.lang.reflect.InvocationTargetException
at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.base/java.lang.reflect.Method.invoke(Method.java:564)
at jdk.javaws@9/com.sun.javaws.Launcher.executeApplication(Launcher.java:1741)
at jdk.javaws@9/com.sun.javaws.Launcher.executeMainClass(Launcher.java:1677)
at jdk.javaws@9/com.sun.javaws.Launcher.doLaunchApp(Launcher.java:1525)
at jdk.javaws@9/com.sun.javaws.Launcher.run(Launcher.java:158)
at java.base/java.lang.Thread.run(Thread.java:844)
Caused by: java.lang.reflect.InaccessibleObjectException: Unable to make protected final void java.awt.Toolkit.setDesktopProperty(java.lang.String,java.lang.Object) accessible: module java.desktop does not "opens java.awt" to unnamed module @1f749ac
at java.base/java.lang.reflect.AccessibleObject.checkCanSetAccessible(AccessibleObject.java:337)
at java.base/java.lang.reflect.AccessibleObject.checkCanSetAccessible(AccessibleObject.java:281)
at java.base/java.lang.reflect.Method.checkCanSetAccessible(Method.java:198)
at java.base/java.lang.reflect.Method.setAccessible(Method.java:192)
at Java9BreaksWhenTest.main(Java9BreaksWhenTest.java:26)
... 9 more
#### Java Web Start Error:
#### Unable to make protected final void java.awt.Toolkit.setDesktopProperty(java.lang.String,java.lang.Object) accessible: module java.desktop does not "opens java.awt" to unnamed module @1f749ac
java.lang.reflect.InaccessibleObjectException: Unable to make protected final void java.awt.Toolkit.setDesktopProperty(java.lang.String,java.lang.Object) accessible: module java.desktop does not "opens java.awt" to unnamed module @1f749ac
at java.base/java.lang.reflect.AccessibleObject.checkCanSetAccessible(AccessibleObject.java:337)
at java.base/java.lang.reflect.AccessibleObject.checkCanSetAccessible(AccessibleObject.java:281)
at java.base/java.lang.reflect.Method.checkCanSetAccessible(Method.java:198)
at java.base/java.lang.reflect.Method.setAccessible(Method.java:192)
at Java9BreaksWhenTest.main(Java9BreaksWhenTest.java:26)
at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.base/java.lang.reflect.Method.invoke(Method.java:564)
at jdk.javaws@9/com.sun.javaws.Launcher.executeApplication(Launcher.java:1741)
at jdk.javaws@9/com.sun.javaws.Launcher.executeMainClass(Launcher.java:1677)
at jdk.javaws@9/com.sun.javaws.Launcher.doLaunchApp(Launcher.java:1525)
at jdk.javaws@9/com.sun.javaws.Launcher.run(Launcher.java:158)
at java.base/java.lang.Thread.run(Thread.java:844)
It is unclear to me where my error is and why java.awt.Toolkit is not available to use via Reflection.
Because Java 9 isn't confusing enough, the right answer is:
That equals sign matters in a JNLP file, but does not on the command line!
On the command line both this:
and
work correctly!