StringTokenizer

java.util(contd..)

Dated: 05-21-2001

StringTokenizer

Sample Code

import java.util.StringTokenizer;

class STDemo {

static String in = "Title=Java;" +

" Author= Mr. ABCD;"+

"Publisher=McGraw-Hill";

public static void main (String args[ ]) {

StringTokenizer st = new StringTokenizer (in, "=;");

//each character in the delimiters string is considered a valid delimiter.

while(st.hasMoreTokens()){

String key = st.nextToken();

String value = st.nextToken();

System.out.println (key + "\t" + val);

}

Output

Title Java

Author Mr. ABCD

Publisher McGraw-Hill

Date

Encapsulates the current date and time. Implements Comparable interface.

Date()

Date(long millis)

Method Summary
`boolean`	after`(`Date `when)` Tests if this date is after the specified date.
`boolean`	before`(`Date `when)` Tests if this date is before the specified date.
Object	clone`()` Return a copy of this object.
`int`	compareTo`(`Date `anotherDate)` Compares two Dates for ordering.
`int`	compareTo`(`Object `o)` Compares this Date to another Object.
`boolean`	equals`(`Object `obj)` Compares two dates for equality.
`long`	getTime`()` Returns the number of milliseconds since January 1, 1970, 00:00:00 GMT represented by this `Date` object.
`int`	hashCode`()` Returns a hash code value for this object.
void	setTime`(long time)` Sets this `Date` object to represent a point in time that is `time` milliseconds after January 1, 1970 00:00:00 GMT.
String	toString`()` Converts this `Date` object to a `String` of the form:

Sample Code

import java.util.*;

class DateDemo{

public static void main (String args[ ]){

Date date = new Date();

// to current date and time

System.out.println(date);

long msec = date.getTime();

System.out.println("Milliseconds since Jan. 1, 1970 GMT =" + msec);

}

Output:

Mon May 21 16:10:40 CST 2001

Milliseconds since Jan. 1, 1970 GMT = 1017192929029

Random

Is a generator of pseudorandom numbers. They are called pseudorandom numbers because they are simply distributed sequences.

Random ()

Random (long seed)

The first version creates a number generator that uses the current tiemas the starting, or seed value. If you use same seed to initialize two Random objects, you will extract the same random sequence.

Method Summary
`Protected int`	next`(int bits)` Generates the next pseudorandom number.
`Boolean`	nextBoolean`()` Returns the next pseudorandom, uniformly distributed `boolean` value from this random number generator's sequence.
`void`	nextBytes`(byte[] bytes)` Generates random bytes and places them into a user-supplied byte array.
`Double`	nextDouble`()` Returns the next pseudorandom, uniformly distributed `double` value between `0.0` and `1.0` from this random number generator's sequence.
`Float`	nextFloat`()` Returns the next pseudorandom, uniformly distributed `float` value between `0.0` and `1.0` from this random number generator's sequence.
`Double`	nextGaussian`()` Returns the next pseudorandom, Gaussian ("normally") distributed `double` value with mean `0.0` and standard deviation `1.0` from this random number generator's sequence.
`int`	nextInt`()` Returns the next pseudorandom, uniformly distributed `int` value from this random number generator's sequence.
`int`	nextInt`(int n)` Returns a pseudorandom, uniformly distributed `int` value between 0 (inclusive) and the specified value (exclusive), drawn from this random number generator's sequence.
`long`	nextLong`()` Returns the next pseudorandom, uniformly distributed `long` value from this random number generator's sequence.
`void`	setSeed`(long seed)` Sets the seed of this random number generator using a single `long` seed.

Piece of Code

Random r = new Random();

double val;

val = r.nextGaussian();