Programming Articles - Page 2923 of 3363

One of the methods in the Timer class is the void schedule(Timertask task, Date time) method. This method schedules the specified task for execution at the specified time. If the time is in the past, it schedules the task for immediate execution.Declaration −The java.util.Timer.schedule(Timertask task, Date time) is declared as follows −public void schedule(Timertask task, Date time)There are few exceptions thrown by the schedule(Timertask task, Date time) method. They are as follows −IllegalArgumentExceptionThis exception is thrown if time.getTime() is negativeIllegalStateExceptionThis exception is thrown if task was scheduled or cancelled beforehand, timer was cancelled, or timer thread terminated.NullPointerExceptionThis exception is thrown ... Read More

One of the methods of the Timer class is the int purge() method. The purge() method removes all the canceled tasks from the timer’s task queue. Invoking this method does not affect the behavior of the timer, rather it eliminates references to the canceled tasks from the queue. The purge() method came into existence since JDK 1.5.The purge() method acts as a medium for space-time tradeoff where it trades time for space. More specifically, the time complexity of the method is proportional to n + c log n, where n is the number of tasks in the queue and c ... Read More

One of the methods of the Timer class is the cancel() method. It is used to terminate the current timer and get rid of any presently scheduled tasks.The java.util.Timer.cancel() method is declared as follows −public void cancel()Let us see a program which uses the cancel() methodExample Live Demoimport java.util.*; public class Example {    Timer t;    public Example(int seconds) {       t = new Timer();       t .schedule(new Running(), seconds);    }    class Running extends TimerTask {       public void run() {          System.out.println("Task is cancelled");         ... Read More

The Timer Class in Java is a facility for threads to plan tasks for future execution in a background thread. Tasks may be executed a single time or multiple times. The Timer class is thread-safe i.e. the threads of the class do not require external synchronization and can share a single Timer object. A point to be noted is that all constructors start a Timer thread.The Timer Class in Java came into existence since JDK 1.3. This class ascends up to large numbers of concurrently scheduled tasks. Internally, it uses a binary heap in the memory to represent its task ... Read More

To get the arc cosine of a given value in Java, we use the java.lang.Math.acos() method. The acos() method accepts a double value whose angle needs to be computed. The range of the angle returned lies in the range 0 to pi. If the argument is NaN or greater than 1 or less than -1 then the result is NaN.Declaration −The java.lang.Math.acos() method is declared as follows −public static double acos(double a)Here, a is the value whose arc cosine is computed.Let us see a program to get the arc cosine of a given value in Java.Example Live Demoimport java.lang.Math; public class ... Read More

To get the arc tangent of a given value in Java, we use the java.lang.Math.atan() method. The atan() method accepts a double value whose angle needs to be computed. The range of the angle returned lies in the range -pi/2 to pi/2. If the argument is NaN, then the result is NaN.When the argument is zero, then the output is a zero with the same sign as the argument.Declaration −The java.lang.Math.atan() method is declared as follows −public static double atan(double a)where a is the value whose arc tangent is computed.Let us see a program to get the arc tangent of ... Read More

In order to generate Random float type numbers in Java, we use the nextFloat() method of the java.util.Random class. This returns the next random float value between 0.0 (inclusive) and 1.0 (exclusive) from the random generator sequence.Declaration −The java.util.Random.nextFloat() method is declared as follows −public float nextFloat()Let us see a program to generate random float type numbers in Java.Example Live Demoimport java.util.Random; public class Example {    public static void main(String[] args) {       Random rd = new Random(); // creating Random object       System.out.println(rd.nextFloat()); // displaying a random float value between 0.0 and 1.0    } ... Read More

In order to get the hyperbolic tangent of a given value in Java, we use the java.lang.Math.tanh() method. The tanh() method accepts an argument in radians and returns the hyperbolic tan of the argument which acts as the angle.Declaration −The java.lang.Math.tanh() is declared as follows −public static double tanh(double x)where, x is the angle in radians.Let us see a program to get the hyperbolic tangent of a given value in Java.Example Live Demoimport java.lang.Math; public class Example {    public static void main(String[] args) {       // get two double numbers in degrees       double x = ... Read More

In order to check if a String has only Unicode letters in Java, we use the isDigit() and charAt() methods with decision-making statements.The isLetter(int codePoint) method determines whether the specific character (Unicode codePoint) is a letter. It returns a boolean value, either true or false.Declaration −The java.lang.Character.isLetter() method is declared as follows −public static boolean isLetter(int codePoint)Here, the parameter codePoint represents the character to be checked.The charAt() method returns a character value at a given index. It belongs to the String class in Java. The index must be between 0 to length()-1.Declaration −The java.lang.String.charAt() method is declared as follows −public ... Read More

To check whether a String contains only unicode letters or digits in Java, we use the isLetterOrDigit() method and charAt() method with decision-making statements.The isLetterOrDigit(char ch) method determines whether the specific character (Unicode ch) is either a letter or a digit. It returns a boolean value, either true or false.Declaration −The java.lang.Character.isLetter() method is declared as follows −public static boolean isLetter(char ch)The charAt() method returns a character value at a given index. It belongs to the String class in Java. The index must be between 0 to length()-1.Declaration −The java.lang.String.charAt() method is declared as follows −public char charAt(int index)Let us ... Read More