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Java break & continue statements Explained [Easy Examples]

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Introduction to Java break and Java continue statements

The Java break and continue statements are used to manage program flow. We can use them in a loop to control loop iterations. These statements let us to control loops and switch statements by enabling us to either break out of the loop or jump to the next iteration by skipping the current loop iteration.

In this tutorial, we will learn about the java break statement and java continue statements. We will cover how we can use them in a while and for loop by taking various examples. We will also see why the break statement is important in switch statements. In a nutshell, this tutorial is going to be one of the most informative tutorials about break and continue statements in Java programming language.

How Java break statement works (flow diagram)

The Java break statement is used to break the loop or switch statements. It breaks the current flow of the program at a specified condition. In the case of an inner loop, it breaks only the inner loop. The following is the simple diagram showing how the break statement works in a loop.

Notice that if the break statement/condition is TRUE then the loop will stop and exit. But if the break condition is FALSE , then body of the loop will be continue to be executed.

How Java continue statement works (flow diagram)

The Java continue statement is used to skip the body of the loop based on condition. So if the condition for continue statement is TRUE then it will skip executing the body of the loop and will go to the start of the loop but if the condition is FALSE then it will continue to go through the remaining body of the loop.

Using Java break and Java continue statements in a while loop

Java while loop is a control flow statement that allows code to be executed repeatedly based on a given Boolean condition. The while loop can be thought of as a repeating if statement. You can learn more about the while loop from the article java while loop. The break statement is used in the while loop to control the loop and exit/stop the loop once the specified condition is achieved and the java continue statement is used to skip the execution of the loop for some specified conditions.

In this section, we will learn how we can use a java break and java continue statements in a while loop by taking examples, but first, let us discuss the syntax of the java break and java continue statements in a while loop.

Syntax of Java break statement in a while loop

Java break statement stops the while loop even if the initial condition is true. The simple syntax of break statement in a while loop looks like this.

while(condition) < if(condition1)< break; >// while loop statements >

When the condition of the if statement inside the loops becomes true, the break statement will execute and the while loop will stop executing further.

Syntax of Java continue statement in a while loop

As we already discussed the java continue statement is used to skip the execution of the while loop for a specified condition. The simple syntax of the java continue statement looks like this:

When the condition of the if statement inside the while loop becomes true, the continue statement will execute, and the rest of the statements of the loop will be skipped and a new iteration will start.

Example-1 Java break statement in a while loop

Now let us take an example and see if the break statement really stops the while loop or not. We will create an infinite while loop by giving a condition that is always going to be true, then we will use the break statement to stop execution when a specific condition becomes true. See the example below:

// class public class Main < public static void main(String[] args)< // variable int num = 0; // while loop while(true)< // condition for break if (num>5) < break; >// printing number System.out.println("counting. "+num); // incrementing the num num++; > > >

counting. 0 counting. 1 counting. 2 counting. 3 counting. 4 counting. 5

Notice that the loop was an infinite loop because the condition in the loop was always true but because of the break statement, we were able to stop the execution of the while loop.

Example-2 Java continue statement in a while loop

Now let us take an example of a continue statement in a while loop. Let us say that we want to print the numbers from 1 to 10 skipping all the numbers that are divisible by 3. See the example below:

// class public class Main < public static void main(String[] args)< // variable int num = 1; // while loop while(num<11)< // condition for continue if (num%3==0)< num++; continue; >// printing number System.out.println("counting. "+num); // incrementing the num num++; > > >

counting. 1 counting. 2 counting. 4 counting. 5 counting. 7 counting. 8 counting. 10

Notice that the java continue statement skipped all the numbers that were divisible by 3.

Java break and continue statement in a for loop

Java for loop provides a concise way of writing the loop structure. The for statement consumes the initialization, condition, and increment/decrement in one line thereby providing a shorter, easy to debug structure of looping. You can read about the for loop from the article about java for loop.

In this section, we will discuss how we can use break and continue statement in a java for loop.

Syntax of Java break statement in a for loop

The syntax of break statement inside for loop is similar to that of while loop. See the simple syntax of break statement inside for loop below:

for(initializer; condition; update) < if(condition1)< break; >// for loop statements >

When the condition of the if statement inside the for loop becomes true, the loop will be stopped.

Syntax of Java continue statement in a for loop

The syntax of the java continue statement inside a for loop is similar to the one in the while loop. See the simple syntax below:

for(initializer; condition; update) < if(condition1)< continue; >// for loop statements > 

When the condition inside the for loop becomes true, the continue statement will execute and all the other statements of the for loop will be skipped.

Example-1 Java break statement in a for loop

Now we know the basic syntax of the break statement in for loop, let us take a practical example and see how it actually works. In the following example, we will have an infinite for loop and we will use the break statement to stop execution once we get to number five.

// class public class Main < public static void main(String[] args)< // variable int num = 0; // java for loop for(; ;)< // condition for break statement if(num==5)< break; >// printing the number System.out.println("counting. "+num); num++; > > >

counting. 0 counting. 1 counting. 2 counting. 3 counting. 4

Notice that we were able to successfully stop the execution of an infinite for loop using the break statement.

Example-2 Java continue statement in a for loop

Now, let us see how we can use the continue statement in java for loop. In the following example, we will print all the numbers from 1 to 10 excluding the multiples of 3. See the example below:

// class public class Main < public static void main(String[] args)< // java for loop for(int i =1; i// printing the number System.out.println("counting. "+i); > > >

counting. 1 counting. 2 counting. 4 counting. 5 counting. 7 counting. 8 counting. 10

Notice that we were able to skip all the numbers divisible by 3.

Java break statement in a switch statement

The switch statement is a multi-way branch statement. It provides an easy way to dispatch execution to different parts of code based on the value of the expression. Basically, the expression can be a byte, short, char, and int primitive data types. You can read more about switch statements from an article java switch statements. In this section, we will see how we can use the break statement inside java switch statements. But first, let us see learn the syntax.

Syntax of Java break statement in a switch statement

The basic syntax of the Java break command in a switch statement is a little bit different than the while loop and for loop one. Because here we don’t need to put if statement explicitly for a break statement. In fact, the cases act like if statements and we have to add the break command after each case. The simple syntax looks like this;

Notice that there are break statements after each case and when one of the cases becomes true, the break statement will be executed and stops the switch statement.

Example-1 Java break statement in switch statement

Now let us take an example and see how break statements in java switch works. See the example below:

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Branching Statements

The break statement has two forms: labeled and unlabeled. You saw the unlabeled form in the previous discussion of the switch statement. You can also use an unlabeled break to terminate a for , while , or do-while loop, as shown in the following BreakDemo program:

class BreakDemo < public static void main(String[] args) < int[] arrayOfInts = < 32, 87, 3, 589, 12, 1076, 2000, 8, 622, 127 >; int searchfor = 12; int i; boolean foundIt = false; for (i = 0; i < arrayOfInts.length; i++) < if (arrayOfInts[i] == searchfor) < foundIt = true; break; > > if (foundIt) < System.out.println("Found " + searchfor + " at index " + i); >else < System.out.println(searchfor + " not in the array"); >> >

This program searches for the number 12 in an array. The break statement, shown in boldface, terminates the for loop when that value is found. Control flow then transfers to the statement after the for loop. This program’s output is:

An unlabeled break statement terminates the innermost switch , for , while , or do-while statement, but a labeled break terminates an outer statement. The following program, BreakWithLabelDemo , is similar to the previous program, but uses nested for loops to search for a value in a two-dimensional array. When the value is found, a labeled break terminates the outer for loop (labeled «search»):

class BreakWithLabelDemo < public static void main(String[] args) < int[][] arrayOfInts = < < 32, 87, 3, 589 >, < 12, 1076, 2000, 8 >, < 622, 127, 77, 955 >>; int searchfor = 12; int i; int j = 0; boolean foundIt = false; search: for (i = 0; i < arrayOfInts.length; i++) < for (j = 0; j < arrayOfInts[i].length; j++) < if (arrayOfInts[i][j] == searchfor) < foundIt = true; break search; >> > if (foundIt) < System.out.println("Found " + searchfor + " at " + i + ", " + j); >else < System.out.println(searchfor + " not in the array"); >> >

This is the output of the program.

The break statement terminates the labeled statement; it does not transfer the flow of control to the label. Control flow is transferred to the statement immediately following the labeled (terminated) statement.

The continue Statement

The continue statement skips the current iteration of a for , while , or do-while loop. The unlabeled form skips to the end of the innermost loop’s body and evaluates the boolean expression that controls the loop. The following program, ContinueDemo , steps through a String , counting the occurrences of the letter «p». If the current character is not a p, the continue statement skips the rest of the loop and proceeds to the next character. If it is a «p», the program increments the letter count.

class ContinueDemo < public static void main(String[] args) < String searchMe = "peter piper picked a " + "peck of pickled peppers"; int max = searchMe.length(); int numPs = 0; for (int i = 0; i < max; i++) < // interested only in p's if (searchMe.charAt(i) != 'p') continue; // process p's numPs++; >System.out.println("Found " + numPs + " p's in the string."); > >

Here is the output of this program:

To see this effect more clearly, try removing the continue statement and recompiling. When you run the program again, the count will be wrong, saying that it found 35 p’s instead of 9.

A labeled continue statement skips the current iteration of an outer loop marked with the given label. The following example program, ContinueWithLabelDemo , uses nested loops to search for a substring within another string. Two nested loops are required: one to iterate over the substring and one to iterate over the string being searched. The following program, ContinueWithLabelDemo , uses the labeled form of continue to skip an iteration in the outer loop.

class ContinueWithLabelDemo < public static void main(String[] args) < String searchMe = "Look for a substring in me"; String substring = "sub"; boolean foundIt = false; int max = searchMe.length() - substring.length(); test: for (int i = 0; i > foundIt = true; break test; > System.out.println(foundIt ? "Found it" : "Didn't find it"); > >

Here is the output from this program.

The return Statement

The last of the branching statements is the return statement. The return statement exits from the current method, and control flow returns to where the method was invoked. The return statement has two forms: one that returns a value, and one that doesn’t. To return a value, simply put the value (or an expression that calculates the value) after the return keyword.

The data type of the returned value must match the type of the method’s declared return value. When a method is declared void , use the form of return that doesn’t return a value.

The Classes and Objects lesson will cover everything you need to know about writing methods.

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