joint strings

heavenflying

1.String tempStr="abc"+"c";
2.StringBuffer sb=sb.append("xx")
3.StringBuffer sb=sb.insert(sb.length(),"xx")


String buffers are used by the compiler to implement the binary string concatenation operator +. For example, the code:
     x = "a" + 4 + "c"

is compiled to the equivalent of:
x = new StringBuffer().append("a").append(4).append("c").toString()  
The principal operations on a StringBuffer are the append and insert methods, which are overloaded so as to accept data of any type. Each effectively converts a given datum to a string and then appends or inserts the characters of that string to the string buffer. The append method always adds these characters at the end of the buffer; the insert method adds the characters at a specified point.


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