Description Yann-Gaël Guéhéneuc 2002-07-10 02:34:38 EDT

Hello,

    I wrote the following code, which is part of a Java project, *not* a
plug-in. It compiles fine with the appropriate class-path:

public class ASTTest {
    public static void main(final String[] args) {
        CompilationUnit compilationUnit =
            AST.parseCompilationUnit(
                "class A { private int i; }".toCharArray());
        compilationUnit.accept(new ASTVisitor() {
            public boolean visit(final TypeDeclaration node) {
                System.out.println(node.getName());
                return true;
            }
        });
    }
}

    When I run it, I get an exception:

java.lang.NullPointerException
    at org.eclipse.jdt.core.JavaCore.getOptions(JavaCore.java:1224)
    at
org.eclipse.jdt.core.dom.CompilationUnitResolver.parse(CompilationUnitResolv
er.java:180)
    at org.eclipse.jdt.core.dom.AST.parseCompilationUnit(AST.java:359)
    at yann.test.ast.ASTTest.main(ASTTest.java:39)
Exception in thread "main"

    It seems to me that the AST class is tightly coupled with the plug-in
management mechanism. Indeed, the exception arises in class JavaCore at the
following line:

    public static Hashtable getOptions() {

        Hashtable options = new Hashtable(10);

        // see #initializeDefaultPluginPreferences() for changing default
settings
        Preferences preferences = getPlugin().getPluginPreferences();
        ///////////////////////////////////////////////////////////// Here
        HashSet optionNames =
JavaModelManager.getJavaModelManager().OptionNames;

        // get preferences set to their default
        String[] defaultPropertyNames = preferences.defaultPropertyNames();
        for (int i = 0; i < defaultPropertyNames.length; i++){
            String propertyName = defaultPropertyNames[i];
            if (optionNames.contains(propertyName)){
                options.put(propertyName,
preferences.getString(propertyName));
            }
        }
        // get preferences not set to their default
        String[] propertyNames = preferences.propertyNames();
        for (int i = 0; i < propertyNames.length; i++){
            String propertyName = propertyNames[i];
            if (optionNames.contains(propertyName)){
                options.put(propertyName,
preferences.getString(propertyName));
            }
        }
        // get encoding through resource plugin
        options.put(CORE_ENCODING, ResourcesPlugin.getEncoding());

        return options;
    }

    Because the JavaCode class is never initialized, the private static
field (!) JAVA_CORE_PLUGIN is set to null and thus the getPlugin() method
returns null.

    Yann-Gaël Guéhéneuc