Java判断一个字符是否是数字的几种方法的代码

在工作期间，将写内容过程经常用到的一些内容段做个记录，下面内容是关于Java判断一个字符是否是数字的几种方法的内容，希望能对码农们有好处。

public class Test
{
public static void main(String[] args)
{
char[] ch =
{
\'a\', \'1\', \'b\', \'2\', \'c\', \'3\', \'d\', \'4\',
};
System.out.println(ch[0] + \": \" + isDigitA(ch[0]));
System.out.println(ch[1] + \": \" + isDigitA(ch[1]));
System.out.println(ch[2] + \": \" + isDigitB(ch[2]));
System.out.println(ch[3] + \": \" + isDigitB(ch[3]));
System.out.println(ch[4] + \": \" + isDigitC(ch[4]));
System.out.println(ch[5] + \": \" + isDigitC(ch[5]));
System.out.println(ch[6] + \": \" + isDigitD(ch[6]));
System.out.println(ch[7] + \": \" + isDigitD(ch[7]));
}

private static boolean isDigitA(char ch)
{
return Character.isDigit(ch);
}

private static boolean isDigitB(char ch)
{
Pattern pattern = Pattern.compile(\"[0-9]\");
return pattern.matcher(String.valueOf(ch)).matches();
}

private static boolean isDigitC(char ch)
{
if (ch < 48 || ch > 57)
return false;
else
return true;
}

private static boolean isDigitD(char ch)
{
try
{
int i = Integer.parseInt(String.valueOf(ch));
return true;
}
catch (NumberFormatException e)
{
e.printStackTrace();
return false;
}

}
}