String str = "speEd=2000MHz";
Pattern p = Pattern.compile("(?i).*?=(\\d*)");
Matcher m = p.matcher(str);
m.find();
System.out.println(m.group(1));

------解决方案--------------------
Java code
String s = "speed=2000MHz1024";
String num = s.replaceAll("speed\\s*=\\s*(\\d+).*", "$1");
System.out.println(num);

------解决方案--------------------
Pattern p = Pattern.compile("\\d+");
Matcher m = p.matcher(arg0);

if(m.find())
String num = m.group(0);
这样不是取到数据了吗？

------解决方案--------------------
Java code
public String get() {
    String str = "speed=2000MHz";
    return "2000";
}