Unfortunately, many designers have still not learnt that the special null pointer or null object is an equally bad idea.
遗憾的是，许多设计者并没有认识到空指针或空对象带来的危害。
But as we hope we've shown in the table, that really represents an array with a single element whose value is null, not a null array.
但是，正如我们希望的，在表中已经显示，它真正表示的是含有单一元素的数组，元素的值为“零”(null)，而不是一个“零”(null)数组。
Elements in positions 11 and up do not exist (note that this is not the same as being NULL). Therefore, a statement such as.
位置11以及更高位置中的元素都不存在(请注意这不同于NULL)。
Similarly, the thread local password is checked and used if not null (and reset to null after use.)
类似地，仍将检查线程本地密码，如果不为空，则使用它(并且在使用后重新设置为空)。
But usually these attributes are not needed, so specifying NULL is the norm.
但是通常并不需要这些属性，所以正常做法是指定NULL。
The first one asserts that the calculator instance object is not null, i.e. it exists.
第一个宣称这个计数器实例对象不是空，就像它实际存在一样。
If the string to be searched is not found and neither argument is null, the result is 0.
如果没有找到搜索字符串，并且参数都不为空，则所得的结果是0。
The unit test methods first verify that the object provided is not null, and then perform one or more very basic actions on the object.
单元测试方法首先验证所提供的对象不是空的，然后对该对象执行一个或多个非常基础的操作。
Initially, this routine checks if the passed inquiry context is not NULL and is for a group member inquiry.
这个例程首先检查传递的查询上下文是否非null，以及是否是用于组成员查询的上下文。
If this checkbox is not selected, the generated WSDL is set to (null), as shown in Listing 7.
如果这个复选框没有选择，那么产生的WSDL的设置为(空的)，如列表7所示。
This method will return null if the focus owner is not in the same context as the calling thread.
如果该焦点所有者未和调用线程处于同一个上下文中，那么该方法会返回空。
Several wiring layouts are in use, because the null modem connection is not covered by a standard.
有多种连接方式可供选择，因为标准中并未涵盖零调制解调器连接。
If the customer number is not null, that is, the customer is already known, the left hand path is followed (2), and the customer data is retrieved from the customer registration service (3).
如果客户编号不为空，即客户是已知客户，则遵循左侧的路径(2)，并从客户注册服务中检索客户数据(3)。
One of the problems with not entering this data in regular RDBMS columns is that no rules are defined-no data types, not NULL identifiers and so forth.
未在常规的RDBMS列中输入该数据导致的问题之一是没有定义任何规则——没有数据类型和NOT NULL标识符等。
In lines 22 through 34 you select an operating system that is not NULL from the list obtained in previous step.
从第22行到第34行从上一步中获得的数组中选择一个不为空的操作系统。
If the input binding parameter is not NULL, then it means that the endpoint resides on a remote host.
如果输入绑定参数不是NULL，就意味着端点在远程主机上。
If the parameter is pointing to null, then the logs are not archived.
如果该参数值为空，则表示日志没有被归档。
If a default value is not specified, the variable is initialized to NULL.
如果没有指定默认值，则初始变量为NULL。
If the URI does not exist in the internal hash table, a null is returned.
如果内部哈希表中没有URI，将返回空值。
For example, if a before trigger supplies value to a NOT NULL column, then the before trigger is executed first and a value is supplied to the column so that the NOT NULL constraint isn't violated.
例如，如果一个BEFORE触发器给一个NOT null列提供值，那么先执行BEFORE触发器，给列提供值，所以不会违反NOT NULL约束。
A cheque is null and void if any one of the particulars mentioned in the preceding paragraph is not specified thereon.
支票上未记载前款规定事项之一的，支票无效。
The uniqueness is ensured on the NOT NULL values.
确保NOT NULL 值的惟一性。
The code in listing 11 first checks if the response passed is null, and, if not, then checks if the required fields are null.
清单11中的代码首先检查传递的响应是否为null，如果不是，则检查所需字段是否为null。
The best practice is not to pass an array with null elements between Web service clients and servers.
最佳的实例不是将含有空元素的数组传递到Web服务的客户端及服务器上。
For example, data classified as "unknown" usually indicates a column that is null or empty and probably not used.
例如，类别为“未知”的数据通常表明一个列只有null值或者为空，可能不被使用。
Because null is not a valid default value for an annotation, I provide some basic defaults that can be easily tested for, so I can identify the value that was specified.
由于null不是标注的有效默认值，因此这里提供了一些便于测试的基本默认值，以便识别被指定的值。
This tag determines whether or not the field in the name attribute is null.
这个标签确定name属性中的字段是否为空。
The above error can occur if the Sybase existing table definition declares one of the columns to be NOT NULL but there is no value for that column in one of the records of the result set.
如果sybase现有表定义声明某一列为NOT NULL，但是在结果集中的某一行记录在那一列没有值，就可能发生上述错误。
A general, good practice is not to allow null (that is, no value) columns in a relational database, because when you attempt to read such a column, you get a null value exception.
通常，一种优秀的实践就是不要在关系数据库中使用null(即没有值)列，因为当您试图读取这类列时，您将得到一个null值异常。
The reason the idiom in Listing 3 is deficient is because obj is not guaranteed to be non-null after the body of the if block completes.
清单3中的风格不够好的原因在于，if块的主体结束之后ob j不一定是非空值。
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