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String Object Immutable Confusion

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Join Date: Feb 2005

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Gink

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Question about string editing

Feb 4th, 2005

Topic is misleading I edited it.

What would be the best way to put a period at the end of a sentence without just adding it to the last word or last variable etc.

Like say i had
String s = "Hello I am a sentence";

what would be the best way to add a period to the end?

Last edited by Gink; Feb 4th, 2005 at 6:42 pm. Reason: Googled

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duckman

Re: String Object Immutable Confusion

Feb 4th, 2005

s=s+".";

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Re: String Object Immutable Confusion

Feb 4th, 2005

lol, i meant the harder way I guess not the best. Is there a way of telling where a period should be by using some type of regular expression or string method?

Also, is this the best way for capitalizing the first Character in a string?

String s = "im a non capitalized sentence!";
char c;
c = s.charAt(0);
Character.toUpperCase(c)
s = s.replaceFirst(s.charAt(0),c)

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Re: String Object Immutable Confusion

Feb 4th, 2005

One more question, Say I have like 5 lines of text in a string
String s = "5 lines of text(pretend)"
and I want to reset this every time like s = ""
should I call System.gc() after I set s to another set of text(5 lines)?

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duckman

Re: String Object Immutable Confusion

Feb 5th, 2005

no, there's no need.

String literals aren't affected by garbage collection, and anyway calling System.gc() isn't guaranteed to do anything

The only reason to use it is to hint the JVM that now would be a nice time to clear up memory before you start a resource intensive operation (either CPU or RAM), but otherwise it's pretty useless.

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duckman

Re: String Object Immutable Confusion

Feb 5th, 2005

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Originally Posted by Gink

lol, i meant the harder way I guess not the best. Is there a way of telling where a period should be by using some type of regular expression or string method?

Also, is this the best way for capitalizing the first Character in a string?

String s = "im a non capitalized sentence!";
char c;
c = s.charAt(0);
Character.toUpperCase(c)
s = s.replaceFirst(s.charAt(0),c)

Ah, you want a harder way?

 Help with Code Tags 
 Java Syntax (Toggle Plain Text) 
String theString = "Hello World";
String theNewString = ((new StringBuffer(theString)).append(".")).toString();
String theString = "Hello World";
String theNewString = ((new StringBuffer(theString)).append(".")).toString();

A more efficient way to capitalise your first character would be to turn your String into a char array, capitalise element 0 in that, and then turn it back into a String.
Saves a few string operations.

 Help with Code Tags 
 Java Syntax (Toggle Plain Text) 
String theString = "hello world";
char[] theArray = theString.toCharArray();
theArray[0] = Character.toUpperCase(theArray[0]);
String theOtherString = new String(theArray);
String theString = "hello world";
char[] theArray = theString.toCharArray();
theArray[0] = Character.toUpperCase(theArray[0]);
String theOtherString = new String(theArray);