PMD规则之Security Code Guidelines

·  MethodReturnsInternalArray: Exposing internal arrays directly allows the user to modify some code that could be critical. It is safer to return a copy of the array.

翻译   方法返回内部数组：暴露内部数组直接允许用户修改的代码会是非常危险的，返回一个数组的copy是安全的做法

代码示例：

public class SecureSystem {

  UserData [] ud;

  public UserData [] getUserData() {

      // Don't return directly the internal array, return a copy

      return ud;

  }

}

·  ArrayIsStoredDirectly: Constructors and methods receiving arrays should clone objects and store the copy. This prevents that future changes from the user affect the internal functionality.

翻译   数组被直接存储：构造器和方法接收数组应该clone对象并保存副本，这会阻止用户将来的改变影响内部的功能。

代码示例：

public class Foo {

 private String [] x;

  public void foo (String [] param) {

      // Don't do this, make a copy of the array at least

      this.x=param;

  }

}