Introduction to Programming in Java/Strings

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Strings are a collection of characters implemented under the String class. However, they may also appear directly in the source code.

String operations[edit]

The only operation permitted on a string is the + operator. In the context of a string, this operator performs concatenation. The value on the right, a string, is appended to the string on the left.

Strings can also be concatenated with integers or other numbers. If this is the case, the variable or object is automatically converted to a string.

String performance[edit]

Even though you may be able to concatinate strings indefinitely, this is not the best means to do what you want. Since strings are immutable objects, attemtping to change a string will create a new string object, and making identical copies of the strings.

If you need to constantly append characters to a string, you may want to use a StringBuilder class.


String constructors[edit]

You can also create strings using these methods. Explanation to below every example of the String constructor.

	
String aString= new String();
// aString is a reference to an empty string. aString can be any name that you want to name the variable
	
String aGreeting;
// aGreeting is reference to a String
aGreeting = new String("Hello world");


Greeting1 = "Hello world";
// Shortcut for constructing String objects.
String Greeting2 = new String(Greeting1);
// Greeting2 is a copy of the String Greeting1


Project: Introduction to Programming in Java
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