Class OperatorWrapCheck

Checks the policy on how to wrap lines on operators.

• Property option - Specify policy on how to wrap lines. Type is com.puppycrawl.tools.checkstyle.checks.whitespace.WrapOption. Default value is nl.
• Property tokens - tokens to check Type is java.lang.String[]. Validation type is tokenSet. Default value is: QUESTION, COLON, EQUAL, NOT_EQUAL, DIV, PLUS, MINUS, STAR, MOD, SR, BSR, GE, GT, SL, LE, LT, BXOR, BOR, LOR, BAND, LAND, TYPE_EXTENSION_AND, LITERAL_INSTANCEOF.

To configure the check:

 <module name="OperatorWrap"/>
 

Example:

 class Test {
     public static void main(String[] args) {
         String s = "Hello" +
         "World"; // violation, '+' should be on new line

         if (10 ==
                 20) { // violation, '==' should be on new line.
         // body
         }
         if (10
                 ==
                 20) { // ok
         // body
         }

         int c = 10 /
                 5; // violation, '/' should be on new line.

         int d = c
                 + 10; // ok
     }

 }
 

To configure the check for assignment operators at the end of a line:

 <module name="OperatorWrap">
   <property name="tokens"
     value="ASSIGN,DIV_ASSIGN,PLUS_ASSIGN,MINUS_ASSIGN,STAR_ASSIGN,MOD_ASSIGN,
            SR_ASSIGN,BSR_ASSIGN,SL_ASSIGN,BXOR_ASSIGN,BOR_ASSIGN,BAND_ASSIGN"/>
   <property name="option" value="eol"/>
 </module>
 

Example:

 class Test {
     public static void main(String[] args) {
             int b
                     = 10; // violation, '=' should be on previous line
             int c =
                     10; // ok
             b
                     += 10; // violation, '+=' should be on previous line
             b +=
                     10; // ok
             c
                     *= 10; // violation, '*=' should be on previous line
             c *=
                     10; // ok
             c
                     -= 5; // violation, '-=' should be on previous line
             c -=
                     5; // ok
             c
                     /= 2; // violation, '/=' should be on previous line
             c
                     %= 1; // violation, '%=' should be on previous line
             c
                     >>= 1; // violation, '>>=' should be on previous line
             c
                 >>>= 1; // violation, '>>>=' should be on previous line
         }
         public void myFunction() {
             c
                     ^= 1; // violation, '^=' should be on previous line
             c
                     |= 1; // violation, '|=' should be on previous line
             c
                     &=1 ; // violation, '&=' should be on previous line
             c
                     <<= 1; // violation, '<<=' should be on previous line
     }
 }
 

Parent is com.puppycrawl.tools.checkstyle.TreeWalker

Violation Message Keys:

• line.new
• line.previous