java去除字符串中的空格、回车、换行符、制表符

java去除字符串中的空格、回车、换行符、制表符
import java.util.regex.Matcher;
import java.util.regex.Pattern;
public class StringUtil {

public static void replaceBlank()
{
Pattern p = Pattern.compile("//s*|/t|/r|/n");
String str="I am a, I am Hello ok, /n new line ffdsa!";
System.out.println("before:"+str);
Matcher m = p.matcher(str);
String after = m.replaceAll("");
System.out.println("after:"+after);
}

public static void main(String[] args) {
replaceBlank();
}

}