java - How string class difference from other classes? -


we can do:

string string = "ourstring";

but can't create objects user defined classes:

userclass uc="";

how java allowing set values directly java.lang.string class only?

java.lang.string special class.

feel free read http://docs.oracle.com/javase/7/docs/api/java/lang/string.html

it says

the string class represents character strings. string literals in java programs, such "abc", implemented instances of class.

...

the java language provides special support string concatenation operator ( + ), , conversion of other objects strings. string concatenation implemented through stringbuilder(or stringbuffer) class , append method. string conversions implemented through method tostring, defined object , inherited classes in java. additional information on string concatenation , conversion, see gosling, joy, , steele, java language specification.

no other classes have special support java language.

you should careful + feature: discussed not safe performance , memory.


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