Hadoop programming _ stringtokenizer class

Stringtokenizer is an application class used to separate strings., Which is equivalent to the split function of VB.
1. Constructor
Public stringtokenizer (string Str)
Public stringtokenizer (string STR, string delim)
Public stringtokenizer (string STR, string delim, Boolean returndelims)
The first parameter is the string to be separated, the second is the delimiter character set combination, and the third parameter indicates whether the separator is returned as a mark. If no Delimiter is specified, the default value is: "\ t \ n \ r \ f"
2. Core Methods
PublicBoolean hasmoretokens ()
PublicString nexttoken ()
PublicString nexttoken (string delim)
PublicInt counttokens ()
In fact, there are three methods. You can also specify the delimiter when the Delimiter is returned, and the last separator is used in the future.
3. Redundant Methods
Public Boolean hasmoreelements ()
Public Boolean hasmoreelements ()
This class implements the enumeration interface, so there is no need to implement these two methods.
Its name is stringtokenizer, and returning an object is meaningless.

Belongs to: Java. util package.

1. constructor.

1. stringtokenizer (string Str): constructs a stringtokenizer object used to parse Str.The default separators in Java are space, tab ('\ t'), line feed (' \ n'), and carriage return ('\ R ')".
2.Stringtokenizer (string STR, string delim): Construct a stringtokenizer object used to parse STR and provide a specified separator.
3.Stringtokenizer (string STR, string delim, Boolean returndelims): Construct a stringtokenizer object used to parse STR and provide a specified separator,Specify whether to return a separator..

2. method.
Note:
1. All methods are public;
2. Writing format: [modifier] <return type> <method name ([parameter list])>
For example:
Static int parseint (string s) indicates that this method (parseint) is a class method (static), the return type is (INT), and the parameter required for the method is a string type.

1. Int counttokens ():Returns the number of times the nexttoken method is called. If constructors 1 and 2 are used, the number of delimiters is returned (Example 2).
2. boolean hasmoretokens ():Returns whether there are delimiters..
3. boolean hasmoreelements (): the result is the same as 2.
4. String nexttoken ():Returns the string from the current position to the next separator..
5. Object nextelement (): the result is the same as 4.
6. String nexttoken (string delim): similar to 4, return results with the specified separator.

Example:
Code:
String S = new string ("the Java platform is the ideal platform for network computing ");
Stringtokenizer ST = new stringtokenizer (s );
System. Out. println ("token Total:" + st. counttokens ());
While (St. hasmoreelements ()){
System. Out. println (St. nexttoken ());
}
Result:
Token Total: 10
The
Java
Platform
Is
The
Ideal
Platform
For
Network
Computing

Example 2:
Code:
String S = new string ("the = Java = platform = is = The = ideal = platform = for = network = computing ");
Stringtokenizer ST = new stringtokenizer (S, "= ",True);
System. Out. println ("token Total:" + st. counttokens ());
While (St. hasmoreelements ()){
System. Out. println (St. nexttoken ());
}
Result:
Token Total: 19
The
=
Java
=
Platform
=
Is
=
The
=
Ideal
=
Platform
=
For
=
Network
=
Computing