Bug 14421 Old .CLASS Files Are Not Deleted
When creating a project that does NOT use source folders (and does not use a bin directory for .class files) the .java and .class files are stored together in the Java package structure. When converting a project to use source folders (and the required bin directory for .class files), the old .class files stored in the Java package structure are NEVER DELETED by Eclipse. This is a bug for Eclipse 1.0 and 2.0. Since I use WSDD 4.0 (which is built on Eclipse 1.0), I've seen compilation errors due to the fact that the compiler/JDT is using old .class files rather than the new ones in the project's bin directory. I have not managed to reproduce the compile errors in build 20020416. But since the old .class files should have been deleted this is still a bug for the latest build.
org.eclipse.jdt.ui/ui/org/eclipse/jdt/internal/ui/preferences/BuildPathsPropertyPage.java
private Control createForClosedProject(Composite parent) {
		Label label= new Label(parent, SWT.LEFT);
		label.setText(JavaUIMessages.getString("BuildPathsPropertyPage.closed_project.message")); 
		
		fBuildPathsBlock= null;
		setValid(true);
		return label;
	}
	
	private IProject getProject() {
		IAdaptable adaptable= getElement();
		if (adaptable != null) {
			IJavaElement elem= (IJavaElement) adaptable.getAdapter(IJavaElement.class);
			if (elem instanceof IJavaProject) {
				return ((IJavaProject) elem).getProject();
			}
		}
		return null;
	}
	
	private boolean isJavaProject(IProject proj) {
		try {
			return proj.hasNature(JavaCore.NATURE_ID);
		} catch (CoreException e) {
			JavaPlugin.log(e);
		}
		return false;
	}	
	
	/*