Class SingleSpaceSeparatorCheck

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); }
 

• Property validateComments - Control whether to validate whitespaces surrounding comments. Type is boolean. Default value is false.

To configure the check:

 <module name="SingleSpaceSeparator"/>
 

Example:

 int foo()   { // violation, 3 whitespaces
   return  1; // violation, 2 whitespaces
 }
 int fun1() { // OK, 1 whitespace
   return 3; // OK, 1 whitespace
 }
 void  fun2() {} // violation, 2 whitespaces
 

To configure the check so that it validates comments:

 <module name="SingleSpaceSeparator">
   <property name="validateComments" value="true"/>
 </module>
 

Example:

 void fun1() {}  // violation, 2 whitespaces before the comment starts
 void fun2() { return; }  /* violation here, 2 whitespaces before the comment starts */

 /* violation, 2 whitespaces after the comment ends */  int a;

 String s; /* OK, 1 whitespace */

 /**
 * This is a Javadoc comment
 */  int b; // violation, 2 whitespaces after the javadoc comment ends

 float f1; // OK, 1 whitespace

 /**
 * OK, 1 white space after the doc comment ends
 */ float f2;
 

Parent is com.puppycrawl.tools.checkstyle.TreeWalker

Violation Message Keys:

• single.space.separator