Lets observe behavior of Introduce Constatn "Replace all occurrences" checkbox (which works properly) and than compare it to Introduce Parameter "Replace all occurrences" checkbox (which doesn't work properly).

1. Create two separated classes OneOccurrence and TwoOccurrences:

public class OneOccurrence {
    public void method(){
        System.out.println("text");
    }
}

public class TwoOccurrences {
    public void method(){
        System.out.println("text");
        String s = "text";
    }
}

2) Select "text" in OneOccurrence class and using Alt+Shift+C invoke Introduce Constant dialog - note, that "Replace All Occurrences" checkbox is DISABLED. Press cancel and using Alt+Shift+P invoke Introduce Parameter dialog - "Replace All Occurrences" checkbox in Introduce Parameter dialog is now ENABLED, although there is only one occurrence.

>> "Replace All Occurrences" checkbox should be disabled when only one occurence.

3) Select "text" in TwoOccurrences class and using Alt+Shift+C invoke Introduce Constant dialog - note, that "Replace All Occurrences" checkbox have caption "Replace All Occurrences (2)". Press cancel and using Alt+Shift+P invoke Introduce Parameter dialog - "Replace All Occurrences" checkbox in Introduce Parameter dialog have now caption "Replace All Occurrences".

>> "Replace All Occurrences" should have following text "Replace All Occurrences (occurences_count)" than more then one occurrences.

Product Version: NetBeans IDE 7.4 RC1 (Build 201309152201)
Java: 1.7.0_40; Java HotSpot(TM) Client VM 24.0-b56
Runtime: Java(TM) SE Runtime Environment 1.7.0_40-b43
System: Windows 7 version 6.1 running on x86; Cp1252; en_US (nb)