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Java 如何检查给定的字符串数组是否返回null?_Java_Arrays_String - Fatal编程技术网

Java 如何检查给定的字符串数组是否返回null?

Java 如何检查给定的字符串数组是否返回null?,java,arrays,string,Java,Arrays,String,我想检查字符串数组给出值还是null的条件 字符串函数: String rowData[] = (String[]) ArrayUtils.subarray(DataArray, startIndex, (startIndex + maxColumnCount)); if(rowData not null) { } 数据数组的值来自: String DataArray[] = request.getParam

我想检查字符串数组给出值还是null的条件

字符串函数:

String rowData[] = (String[]) ArrayUtils.subarray(DataArray, startIndex,
                                         (startIndex + maxColumnCount));

if(rowData not null)
{

}
数据数组的值来自:

String DataArray[] = request.getParameter("values").split(",");

如果条件是什么?

检查数组的长度/大小是否为零

if(DataArray.length != 0)  //something similar to this

无法给定请求参数,并生成null

String dataArrayParam = request.getParameter("values");
String[] dataArray = dataArrayParam == null?
    new String[0] : dataArrayParam.split(",");
一般来说:

if (rowData != null) {
顺便说一句,
String[]
是一种更为传统的表示法,
stringa[]
来自Java早期的C兼容性。

简单检查一下

if(DataArray != null)
{
     String rowData[] = (String[]) ArrayUtils.subarray(DataArray, startIndex,
                                         (startIndex + maxColumnCount));

     if(rowData not null)
     {

     }
}

这是什么语言,
C#
?好的:Java-谢谢;-))是的,但我想用rowData检查它,它现在正在工作。Thnks:)