Article Categories
- All Categories
-
Data Structure
-
Networking
-
RDBMS
-
Operating System
-
Java
-
MS Excel
-
iOS
-
HTML
-
CSS
-
Android
-
Python
-
C Programming
-
C++
-
C#
-
MongoDB
-
MySQL
-
Javascript
-
PHP
-
Economics & Finance
Programming Articles
Page 1547 of 2547
When to use new operator in C++ and when it should not be used?
Use of the new operator signifies a request for the memory allocation on the heap. If the sufficient memory is available, it initializes the memory and returns its address to the pointer variable.The new operator should only be used if the data object should remain in memory until delete is called. Otherwise if the new operator is not used, the object is automatically destroyed when it goes out of scope. In other words, the objects using new are cleaned up manually while other objects are automatically cleaned when they go out of scope.The following is the syntax of new operator.pointer_variable ...
Read MoreParsing and Formatting a Big Integer into Binary in Java
Firstly, take two BigInteger objects and set values.BigInteger one, two; one = new BigInteger("99"); two = new BigInteger("978");Now, parse BigInteger object “two” into Binary.two = new BigInteger("1111010010", 2); String str = two.toString(2);Above, we have used the following constructor. Here, radix is set as 2 for Binary for both BigInteger constructor and toString() method.BigInteger(String val, int radix)This constructor is used to translate the String representation of a BigInteger in the specified radix into a BigInteger.The following is an example −Exampleimport java.math.*; public class Demo { public static void main(String[] args) { BigInteger one, two; ...
Read MoreSchedule a task for execution in Java after a given delay
One of the methods in the Timer class is the void schedule(Timertask task, long delay) method. This method schedules the specified task for execution after the specified delay.Declaration −The java.util.Timer.schedule(Timertask task, long delay) is declared as follows −public void schedule(Timertask task, long delay)There are few exceptions thrown by the schedule(Timertask task, long delay) method. They are as follows −IllegalArgumentExceptionThis exception is thrown if delay is negative, or delay + System.currentTimeMillis() is negative.IllegalStateExceptionThis exception is thrown if task was scheduled or cancelled beforehand, timer was cancelled, or timer thread terminated.NullPointerExceptionThis exception is thrown if the task is null.Let us see a ...
Read MoreLeft pad a string in Java
To left pad a string, use the String.format and set the spaces.String.format("|%20s|", "demotext")If you add 30 above, it will display the first string after 30 spaces from the beginning.String.format("|%30s|", "demotext")Examplepublic class Demo { public static void main(String []args) { System.out.print(String.format("|%20s|", "demotext")); System.out.println("Left padded!"); } }Output| demotext|Left padded
Read MoreHow to schedule tasks in Java to run for repeated fixed-delay execution, beginning at the specified time
One of the methods in the Timer class is the void schedule(TimerTask task, Date firstTime, long period) method. This method schedules tasks for repeated fixed-delay execution, beginning at the specified time.In fixed-delay execution, each execution is scheduled with respect to the original execution time of the preceding execution. If an execution is delayed for a particular reason (case in point, garbage collection), the subsequent executions will be delayed as well.Declaration −The java.util.Timer.schedule(TimerTask task, Date firstTime, long period) is declared as follows −public void schedule(TimerTask task, Date firstTime, long period)Here, task is the task to be scheduled, firstTime is the first ...
Read Morestrcat() vs strncat() in C++
Both strcat() and strncat() are predefined string functions in C++. Details about these are given as follows.strcat()This function is used for concatenation. It appends a copy of the source string at the end of the destination string and returns a pointer to the destination string. The syntax of strcat() is given as follows.char *strcat(char *dest, const char *src)A program that demonstrates strcat() is given as follows.Example#include #include using namespace std; int main() { char str1[20] = "Mangoes are "; char str2[20] = "yellow"; strcat(str1, str2); cout
Read MoreParsing and Formatting a Byte Array into Binary in Java
Set a BigInteger object.BigInteger one;Now, create a ByteArray.byte byteArr[] = new byte[] { 0x1, 0x00, 0x00 }; one = new BigInteger(byteArr);For Binary, we have used 2 as the toString() method parameter.String strResult = one.toString(2);The following is an example −Exampleimport java.math.*; public class Demo { public static void main(String[] args) { // BigInteger object BigInteger one; byte byteArr[] = new byte[] { 0x1, 0x00, 0x00 }; one = new BigInteger(byteArr); String strResult = one.toString(2); System.out.println("ByteArray to Binary = "+strResult); } }OutputByteArray to Binary = 10000000000000000
Read MoreDeclare static variables and methods in an abstract class in Java
If a method is declared as static, it is a member of a class rather than belonging to the object of the class. It can be called without creating an object of the class. A static method also has the power to access static data members of the class.A static variable is a class variable. A single copy of the static variable is created for all instances of the class. It can be directly accessed in a static method.An abstract class in Java is a class that cannot be instantiated. It is mostly used as the base for subclasses to ...
Read MoreSchedule a task for repeated fixed delay execution in Java
In fixed-delay execution, each execution is scheduled with respect to the original execution time of the preceding execution. If an execution is delayed for a particular reason (case in point, garbage collection), the subsequent executions will be delayed as well.There are two ways in which a task can be scheduled for repeated fixed-delay execution. They are as follows −Scheduling a task for repeated fixed-delay execution at a specified timeScheduling a task for repeated fixed-delay execution after a specified delayScheduling a task for repeated fixed-delay execution at a specified timeThe void schedule(TimerTask task, Date firstTime, long period) method schedules tasks for ...
Read MoreHow to throw a C++ exception?
Exception handling is used to handle the exceptions. We can use try catch block to protect the code. Exception can be thrown anywhere within the code block. The keyword “throw” is used to throw an exception.Here is an example of throw in C++ language,Example#include using namespace std; int display(int x, int y) { if( y == 0 ) { throw "Division by zero condition!"; } return (x/y); } int main () { int a = 50; int b = 0; int c = 0; try { c = display(a, b); cout
Read More