Bug 21183 Class javadoc created during "New Class" operation doesn't fill in variables properly [javadoc] [code manipulation]
If you use the enclosing_type variable in your javadoc comment template, it is not properly filled in when you make a new class (using the New Class dialog). Probably the class should be created, then after creating and saving, javadoc should be added. I suspect the variables don't have valid values yet at the time the javadoc is prepended to the class.
org.eclipse.jdt.ui/ui/org/eclipse/jdt/ui/wizards/NewTypeWizardPage.java
* editable; otherwise it is read-only.
	 */	
	public void setEnclosingType(IType type, boolean canBeModified) {
		fCurrEnclosingType= type;
		fCanModifyEnclosingType= canBeModified;
		String str= (type == null) ? "" : JavaModelUtil.getFullyQualifiedName(type); 
		fEnclosingTypeDialogField.setText(str);
		updateEnableState();
	}
	
	/**
	 * Returns the selection state of the enclosing type checkbox.
	 * 
	 * @return the seleciton state of the enclosing type checkbox
	 */
	public boolean isEnclosingTypeSelected() {
		return fEnclosingTypeSelection.isSelected();
	}
	/**
	 * Sets the enclosing type checkbox's selection state.
	 * 
	 * @param isSelected the checkbox's selection state
	 * @param canBeModified if <code>true</code> the enclosing type checkbox is
	 * modifiable; otherwise it is read-only.
	 */
	public void setEnclosingTypeSelection(boolean isSelected, boolean canBeModified) {
		fEnclosingTypeSelection.setSelection(isSelected);
		fEnclosingTypeSelection.setEnabled(canBeModified);
		updateEnableState();
	}