Bug 16858 Preceding space in package compression pattern sometimes ignored
(In the following discussion, all patterns were entered without the enclosing quote marks.) The pattern "1 " causes one character of each package name to be displayed with a single space separator between them. The pattern " 1 " causes one space to precede the first single-character package name and two spaces to appear between each one. Both of the above cases were expected. However, if you set the patttern to " 1" (i.e. space before, but no space after), no spaces are displayed in the result.
org.eclipse.jdt.ui/ui/org/eclipse/jdt/internal/ui/viewsupport/JavaElementLabels.java
buf.append(CONCAT_STRING);
				getTypeLabel(method.getDeclaringType(), T_FULLY_QUALIFIED, buf);
			}			
			
		} catch (JavaModelException e) {
			JavaPlugin.log(e); 
		}
	}
	
	/**
	 * Appends the label for a field to a StringBuffer. Considers the F_* flags.
	 */	
	public static void getFieldLabel(IField field, int flags, StringBuffer buf) {
		try {
			if (getFlag(flags, F_PRE_TYPE_SIGNATURE) && field.exists()) {
				buf.append(Signature.toString(field.getTypeSignature()));
				buf.append(' ');
			}
			
			
			if (getFlag(flags, F_FULLY_QUALIFIED)) {
				getTypeLabel(field.getDeclaringType(), T_FULLY_QUALIFIED, buf);
				buf.append('.');
			}
			buf.append(field.getElementName());
			
			if (getFlag(flags, F_APP_TYPE_SIGNATURE) && field.exists()) {
				buf.append(DECL_STRING);
				buf.append(Signature.toString(field.getTypeSignature()));
			}