菜鸟编译期错误，请各位大侠帮忙解决一下吧！好心的各位哥哥姐姐们！

[sinianlangzi]

编译期错误：如果用sun公司的源文件，就可以编译；如果是自己新建NOTE就会出现如下面这样的等等编译错误。一直都没搞明白，求各位好心的哥哥姐姐们照顾一下我这个初学都吧！

c:\javapak> javac music5.java
music5.java:6:cannot find symbol
symbol : class string
location: class instrument
public abstract string what();
1 error

源文件：
// A 1d array
import java.util.* ;

abstract class instrument {
int i;
public abstract void play() ;
public string what() {
return "instrument" ;
}
public abstract void adjust() ;
}

class wind extends instrument {
public void play() {
system.out.println("wind.play()") ;
}
public string what(){ return "wind" ; }
public void adjust(){}
}

class percussion extends instrument {
public void play() {
system.out.println("percussion.play()");
}
public string what() { return "percussion" ; }
public void adjust() {}
}

class stringed extends instrument {
public void play() {
system.out.println("stringed.play()") ;
}
public string what() { return "stringed" ;}
public void adjust() {}
}

class brass extends wind {
public void play() {
system.out.println("brass.play()") ;
}
public void adjust() {
system.out.println("brass.adjust()") ;
}
}


class woodwind extends wind {
public void play() {
system.out.println("woodwind.play()") ;
}
public string what() {return "woodwind" ; }
}

public class music4 {
static void tune(instrument i) {
i.play() ;
}
static void tuneall(instrument[] e) {
for(int i=0; i< e.length; i++)
tune(e[i]) ;
}

public static void main(String[] args) {
instrument[] orchestra = new instrument[5];
int i=0;
orchestra[i++] = new wind();
orchestra[i++] = new percussion();
orchestra[i++] = new stringed();
orchestra[i++] = new brass();
orchestra[i++] = new woodwind();
tuneall(orchestra);
}

}

[zjpdhappy]

import java.util.* ;

abstract class instrument {
int i;
public abstract void play() ;
public String what() {
return "instrument" ;
}
public abstract void adjust() ;
}

class wind extends instrument {
public void play() {
System.out.println("wind.play()") ;
}
public String what(){ return "wind" ; }
public void adjust(){}
}

class percussion extends instrument {
public void play() {
System.out.println("percussion.play()");
}
public String what() { return "percussion" ; }
public void adjust() {}
}

class stringed extends instrument {
public void play() {
System.out.println("stringed.play()") ;
}
public String what() { return "stringed" ;}
public void adjust() {}
}

class brass extends wind {
public void play() {
System.out.println("brass.play()") ;
}
public void adjust() {
System.out.println("brass.adjust()") ;
}
}


class woodwind extends wind {
public void play() {
System.out.println("woodwind.play()") ;
}
public String what() {return "woodwind" ; }
}

public class music5 {
static void tune(instrument i) {
i.play() ;
}
static void tuneall(instrument[] e) {
for(int i=0; i< e.length; i++)
tune(e[i]) ;
}

public static void main(String[] args) {
instrument[] orchestra = new instrument[5];
int i=0;
orchestra[i++] = new wind();
orchestra[i++] = new percussion();
orchestra[i++] = new stringed();
orchestra[i++] = new brass();
orchestra[i++] = new woodwind();
tuneall(orchestra);
}

}

[zjpdhappy]

已经编译通过 感想：String和System要大写，文件名一定要和主类的名字相同，编译时注意大小写;楼主的主类是music4，文件名却是music5

[XXKKFF]

String,要大写开头

[yeah920]

string要大写！！

[sinianlangzi]

谢谢各位哥哥姐姐！我该如何把分散给大家呢，别见怪啊！

[sinianlangzi]

刚开始用CSDN！

[XXKKFF]

最上面有一个管理