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In this noncompliant code example, an assignment expression is the outermost expression in an if statement.

public void exampleFunction(Object a, Object b){

  if (a = b) {
    /* ... */
  }

}

While the intent of the code could be to assign b to a and test the value of the result for equality to zero, it is frequently a case of the programmer mistakenly using the assignment operator = instead of the equals operator ==.

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When the assignment of b to a is unintended, this conditional block is now executed when a is equal to b.

public void exampleFunction(Object a, Object b){

  if (a == b) {
    /* ... */
  }

}

When the assignment is intended, the following compliant solution may be used because the programmer's intent is clearer:

public void exampleFunction(Object a, Object b){


  if ((a = b) == true) {
    /* ... */
  }

}

Although it could be preferable to express this same logic as an assignment followed by a conditional:

public void exampleFunction(Object a, Object b){

  a = b;
  if (a == 0) {
    /* ... */
  }

}

Risk Assessment

Errors of omission can result in unintended program flow.

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