Bug 42655 SourceAttachmentBlock does not use dialog font for all widgets [dialogs] [build path]
org.eclipse.jdt.ui/ui/org/eclipse/jdt/internal/ui/wizards/buildpaths/SourceAttachmentBlock.java
status.setError(NewWizardMessages.getString("SourceAttachmentBlock.filename.error.notvalid")); 
					return status;
				}
				fFileVariablePath= JavaCore.getClasspathVariable(varName);
				if (fFileVariablePath == null) {
					status.setError(NewWizardMessages.getString("SourceAttachmentBlock.filename.error.varnotexists")); 
					return status;
				}
				resolvedPath= fFileVariablePath.append(filePath.removeFirstSegments(1));
				
				if (resolvedPath.isEmpty()) {
					status.setWarning(NewWizardMessages.getString("SourceAttachmentBlock.filename.warning.varempty")); 
					return status;
				}
				File file= resolvedPath.toFile();
				if (!file.exists()) {				
					String message= NewWizardMessages.getFormattedString("SourceAttachmentBlock.filename.error.filenotexists", resolvedPath.toOSString()); 
					status.setWarning(message);
					return status;
				}						
				
			} else {
				File file= filePath.toFile();
				IResource res= fWorkspaceRoot.findMember(filePath);
				if (res != null && res.getLocation() != null) {
					file= res.getLocation().toFile();
				}
				if (!file.exists()) {
					String message=  NewWizardMessages.getFormattedString("SourceAttachmentBlock.filename.error.filenotexists", filePath.toString()); 
					status.setError(message);