SingleSpaceSeparator
Since Checkstyle 6.19
Description
Checks that non-whitespace characters are separated by no more than one whitespace. Separating characters by tabs or multiple spaces will be reported. Currently, the check doesn't permit horizontal alignment. To inspect whitespaces before and after comments, set the property
validateComments to true.
Setting validateComments to false will ignore cases like:
int i; // Multiple whitespaces before comment tokens will be ignored.
private void foo(int /* whitespaces before and after block-comments will be
ignored */ i) {
Sometimes, users like to space similar items on different lines to the same column position for easier reading. This feature isn't supported by this check, so both braces in the following case will be reported as violations.
public long toNanos(long d) { return d; } // 2 violations
public long toMicros(long d) { return d / (C1 / C0); }
Properties
| name | description | type | default value | since |
|---|---|---|---|---|
| validateComments | Control whether to validate whitespaces surrounding comments. | boolean | false |
6.19 |
Examples
To configure the check:
<module name="Checker">
<module name="TreeWalker">
<module name="SingleSpaceSeparator"/>
</module>
</module>
Example:
class Example1 {
int foo() { // violation 'Use a single space'
return 1; // violation 'Use a single space'
}
void fun1() {}
// violation below 'Use a single space'
void fun2() { return; } /* 2 whitespaces before the comment starts */
/* 2 whitespaces after the comment ends */ int a;
String s; /* OK, 1 whitespace */
/**
* This is a Javadoc comment
*/ int b;
}
To configure the check so that it validates comments:
<module name="Checker">
<module name="TreeWalker">
<module name="SingleSpaceSeparator">
<property name="validateComments" value="true"/>
</module>
</module>
</module>
Example:
class Example2 {
int foo() { // violation 'Use a single space'
return 1; // violation 'Use a single space'
}
void fun1() {}
// 2 violations below
void fun2() { return; } /* 2 whitespaces before the comment starts */
// violation below 'Use a single space'
/* 2 whitespaces after the comment ends */ int a;
String s; /* OK, 1 whitespace */
/**
* This is a Javadoc comment
*/ int b;
// violation above 'Use a single space'
}
Example of Usage
Violation Messages
All messages can be customized if the default message doesn't suit you. Please see the documentation to learn how to.
Fully Qualified Name
com.puppycrawl.tools.checkstyle.checks.whitespace.SingleSpaceSeparatorCheck
Use this fully qualified class name in configuration when an exact class reference is required.