Java中并不常用标签,很多开发者不理解标签是如何工作的。 并且,它们的用法让控制流很难理解,减低了代码的可读性。

如下代码所示:

int matrix[][] = {
  {1, 2, 3},
  {4, 5, 6},
  {7, 8, 9}
};

outer: for (int row = 0; row < matrix.length; row++) {   // Non-Compliant
  for (int col = 0; col < matrix[row].length; col++) {
    if (col == row) {
      continue outer;
    }
    System.out.println(matrix[row][col]);                // Prints the elements under the diagonal, i.e. 4, 7 and 8
  }
}

应该重构为:

for (int row = 1; row < matrix.length; row++) {          // Compliant
  for (int col = 0; col < row; col++) {
    System.out.println(matrix[row][col]);                // Also prints 4, 7 and 8
  }
}