cannot resolve symbol怎么处理???

源代码如下：
package firstPackage;
import java.lang.system;
import java.io.*;

public class Hello{
public String personName;
public void Hello(){};
public String readname() {
int ch;
String name = "";
boolean ok = false;
System.out.println("Please enter your name:");
while (!ok) {
try {
ch = System.in.read();
if (ch<0 || (char)ch == '\n')
ok = true;
else if ((char)ch != '\r')
name = name + (char)ch;
}
catch (IOException e) {
ok = true;
}
}
personName = name;
return name;
}
public static void main (String[] args) {
String name;
Hello myfirst = new Hello();
name = myfirst.readname();
System.out.println("Welcome to the Java World." + name + ".");
System.out.println("And may you success.");
}
}

报错：
Hello.java:2:cannot resolve symbol
symbol:class system
location:package land
import java.lang.system;