Commons Lang、StringUtils.substringBeforeLast()
まんま
import org.apache.commons.lang.StringUtils; public class C2008113000 { public static void main(String[] args) { System.out.println(StringUtils.substringBeforeLast(null, "z")); System.out.println(StringUtils.substringBeforeLast("", "z")); System.out.println(StringUtils.substringBeforeLast("abcba", "b")); System.out.println(StringUtils.substringBeforeLast("abc", "c")); System.out.println(StringUtils.substringBeforeLast("a", "a")); System.out.println(StringUtils.substringBeforeLast("a", "z")); System.out.println(StringUtils.substringBeforeLast("a", null)); System.out.println(StringUtils.substringBeforeLast("a", "")); } }
で、
null abc ab a a a