Admin: 1 версия

2010-06-01T05:19:04Z

1 версия

в 17:44, 31 мая 2010

2010-05-31T17:44:27Z

Новая страница

== Breaking Indefinite Loops ==



<source lang="java">
public class MainClass {
public static void main(String[] args) {
OuterLoop: for (int i = 2;; i++) {
for (int j = 2; j < i; j++) {
if (i % j == 0) {
continue OuterLoop;
}
}
System.out.println(i);
if (i == 107) {
break;
}
}
}
}</source>



<pre class=codeResult>2
3
5
7
11
13
17
19
23
29
31
37
41
43
47
53
59
61
67
71
73
79
83
89
97
101
103
107</pre>

== Labelled breaks breaks out of several levels of nested loops inside a pair of curly braces. ==



<source lang="java">
public class Main {
public static void main(String args[]) {
int len = 100;
int key = 50;
int k = 0;
out: {
for (int i = 0; i < len; i++) {
for (int j = 0; j < len; j++) {
if (i == key) {
break out;
}
k += 1;
}
}
}
System.out.println(k);
}
}</source>



== The break Statement ==

<OL><LI>The break statement is used to break from an enclosing do, while, for, or switch statement.</LI><LI>It is a compile error to use break anywhere else.</LI><LI>"break" breaks the loop without executing the rest of the statements in the block.</LI></OL>
<p>For example, consider the following code</p>



<source lang="java">
public class MainClass {
public static void main(String[] args) {
int i = 0;
while (true) {
System.out.println(i);
i++;
if (i > 3) {
break;
}
}
}
}</source>



<p>The result is</p>
<pre class=codeResult>0
1
2
3</pre>

== The Labeled break Statement ==

<OL><LI>The break statement can be followed by a label.</LI><LI>The presence of a label will transfer control to the start of the code identified by the label.</LI><LI>For example, consider this code.</LI></OL>



<source lang="java">
public class MainClass {
public static void main(String[] args) {
OuterLoop: for (int i = 2;; i++) {
for (int j = 2; j < i; j++) {
if (i % j == 0) {
continue OuterLoop;
}
}
System.out.println(i);
if (i == 37) {
break OuterLoop;
}
}
}
}</source>



<pre class=codeResult>2
3
5
7
11
13
17
19
23
29
31
37</pre>

== Using the break Statement in a Loop: break out from a loop ==



<source lang="java">
public class MainClass {
public static void main(String[] args) {
int count = 50;
for (int j = 1; j < count; j++) {
if (count % j == 0) {
System.out.println("Breaking!!");
break;
}
}
}
}</source>



<pre class=codeResult>Breaking!!</pre>

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Admin: 1 версия

в 17:44, 31 мая 2010