Removing characters in a java string

Question

I want to remove charecters from a string. Example: I have an application that as the users check off the check mark its building the sql script, so if they check female it adds to the String And Gender = 'Female'. and if they select Male it adds And Where gender = 'Male'. The script is working well when adding to string as they check off but when you uncheck a item I am not sure how to remove the char that were added when it was checked. I tried .Replace .ReplaceAll and all the other replace. I know the string I want to remove, why won't it replace it with "".

String SQL; 
SQL += " AND Gender = 'Female'";  
SQL.Replace("AND Gender = 'Female'","");

This won't work!

Surely you have a "Confirm" or "Submit" button somewhere? Why not build the SQL query string after the user confirms their selections? That way when it's time to submit you can simply read off the states of the check boxes directly and build the string in one go instead of removing and inserting strings every time the user changes something. — In silico
– In silico, Commented Dec 20, 2010 at 23:18
That's invalid Java. The method is called replace, not Replace. Please ensure that you post real and compileable code to avoid red herrings. — BalusC
– BalusC, Commented Dec 20, 2010 at 23:21

The Scrum Meister · Accepted Answer · 2010-12-21 00:14:20Z

7

SQL = SQL.replace("AND Gender = 'Female'","");

strings are immutable in java

edited Dec 21, 2010 at 0:14

answered Dec 20, 2010 at 23:17

The Scrum Meister

30.2k8 gold badges69 silver badges65 bronze badges

Sign up to request clarification or add additional context in comments.

1 Comment

Lukasz Over a year ago

It's should be SQL.replace(...) not SQL.Replace(...)

Matthew Purland · Accepted Answer · 2010-12-20 23:19:11Z

1

A java string (java.lang.String) is immutable; it cannot be edited. You can try using StringBuffer (java.lang.StringBuffer) which is a mutable buffer for returning strings.

StringBuffer SQL = new StringBuffer();
SQL.append(" AND Gender = 'Female'");

You can also use replace and delete to remove substrings from the buffer. When you're done editing the buffer simply use SQL.toString().

answered Dec 20, 2010 at 23:19

Matthew Purland

2903 silver badges5 bronze badges

Comments

Hovercraft Full Of Eels · Accepted Answer · 2010-12-20 23:19:56Z

1

Don't use a String if you want something mutable. Instead you're better off using a StringBuilder object. Then when you're done modifying it, you can call toString() on it to get the String you need. The API will show you the methods of this flexible class.

answered Dec 20, 2010 at 23:19

Hovercraft Full Of Eels

286k25 gold badges267 silver badges391 bronze badges

Comments

user467871 · Accepted Answer · 2010-12-21 05:35:15Z

1

String is immutable class. Here is another solution : convert to StringBuffer or StringBuilder and delete from the startIndex to endIndex

String s = "test tes te t ";
String str = new StringBuffer(s).delete(start, end).toString();

for example :
String str = new StringBuffer(s).delete(0, 8).toString();
System.out.println(str); // s te t

answered Dec 21, 2010 at 5:35

user467871

Collectives™ on Stack Overflow

Removing characters in a java string

4 Answers 4

1 Comment

Comments

Comments

Comments

Hot Network Questions

Collectives™ on Stack Overflow

4 Answers 4

1 Comment

Comments

Comments

Comments

Related