Java Loop Control: Mastering Code Repetition and Flow Control
Learn how to control code execution in Java with loop structures like for, while, and do-while loops. Understand when loops are necessary to repeat a block of code multiple times, and explore Java’s control structures that allow complex and flexible execution flows.
Java - Loop Control
When Loops are Required?
There may be a situation when you need to execute a block of code several times. In general, statements are executed sequentially: The first statement in a function is executed first, followed by the second, and so on.
Programming languages provide various control structures that allow for more complicated execution paths.
Loop Statement
A loop statement allows us to execute a statement or group of statements multiple times. The following is the general form of a loop statement in most programming languages:
Java Loops
The Java programming language provides the following types of loops to handle looping requirements:
| Sr.No. | Loop & Description |
|---|---|
| 1 | while loop: Repeats a statement or group of statements while a given condition is true. It tests the condition before executing the loop body. |
| 2 | for loop: Executes a sequence of statements multiple times and abbreviates the code that manages the loop variable. |
| 3 | do...while loop: Similar to a while statement, except that it tests the condition at the end of the loop body. |
| 4 | Enhanced for loop: Introduced in Java 5, this loop is mainly used to traverse a collection of elements, including arrays. |
Loop Control Statements
Loop control statements change execution from its normal sequence. When execution leaves a scope, all automatic objects that were created in that scope are destroyed.
In Java, the following are the loop control statements:
| Sr.No. | Control Statement & Description |
|---|---|
| 1 | break statement: Terminates the loop or switch statement and transfers execution to the statement immediately following the loop or switch. |
| 2 | continue statement: Causes the loop to skip the remainder of its body and immediately retest its condition prior to reiterating. |