regex - Replacing single '' with '\' in Java

Question

How do I replace a single '' with '\'? When I run replaceAll() then I get this error message.

Exception in thread "main" java.util.regex.PatternSyntaxException:
                           Unexpected internal error near index 1 
                                                                  ^
    at java.util.regex.Pattern.error(Pattern.java:1713)
    at java.util.regex.Pattern.compile(Pattern.java:1466)
    at java.util.regex.Pattern.<init>(Pattern.java:1133)
    at java.util.regex.Pattern.compile(Pattern.java:823)
    at java.lang.String.replaceAll(String.java:2190)
    at NewClass.main(NewClass.java:13)
Java Result: 1

My code:

public class NewClass {
    public static void main(String[] args) {
        String str = "C:\Documents and Settings\HUSAIN\My Documents\My Palettes";
        str = str.replaceAll("", "");
        System.out.println(str);
    }
}

Answer 1

String.replaceAll(String,String) is regex.
String.replace(String,String) will do what you want.

The following...

String str = "C:\Documents and Settings\HUSAIN\My Documents\My Palettes";
System.out.println(str);
str = str.replace("", "");
System.out.println(str);

Produces...

C:Documents and SettingsHUSAINMy DocumentsMy Palettes
C:\Documents and Settings\HUSAIN\My Documents\My Palettes