程序没问题，可我想问的是为什么不能执行

public class SchoolTest {
public static void mian (String[]args){
Student st1=new Student ();
Student st2=new Student ();
Teacher te1=new Teacher ();
Teacher te2=new Teacher ();
st1.setschoolname ("重庆大学");
st1.setclassname ("计算机二班");
st1.setname ("王刚");
st1.setcode ("951034");
st1.setsex ("男");
st1.setbirthday ("1975-07-21");
st1.setfamilyaddress ("上海浦东新区");
//我是分隔符╮(╯▽╰)╭
st2.setschoolname ("重庆大学");
st1.setclassname ("计算机三班");
st1.setname ("谢娜");
st1.setcode ("951068");
st1.setsex ("女");
st1.setbirthday ("1975-10-09");
st1.setfamilyaddress ("北京海淀区");
//我是分隔符╮(╯▽╰)╭
te1.setschoolname ("四川大学");
te1.setclassname ("计算机二班");
te1.setname ("赵敏");
te1.setcode ("001234");
te1.setsex ("女");
te1.setbirthday ("1968-04-20");
te1.setfamilyaddress ("重庆市沙坪坝区");
//我是分隔符╮(╯▽╰)╭
te2.setschoolname ("四川大学");
te2.setclassname ("机械系三班");
te2.setname ("赵日天");
te2.setcode ("000001");
te2.setsex ("男");
te2.setbirthday ("1961-02-13");
te2.setfamilyaddress ("成都市区");
//我是分隔符╮(╯▽╰)╭
System.out.println (st1.toString ());
System.out.println (st2.toString ());
System.out.println (te1.toString ());
System.out.println (te2.toString ());
}
}

public class School {
private String schoolName;
private String className;
private String name;
private String code;
private String sex;
private String birthday;
private String address;
public School() {
super();
}
public School(String schoolName, String className, String name, String code, String sex, String birthday,
String address) {
super();
this.schoolName = schoolName;
this.className = className;
this.name = name;
this.code = code;
this.sex = sex;
this.birthday = birthday;
this.address = address;
}

public String getSchoolName() {
    return schoolName;
}
public void setSchoolName(String schoolName) {
    this.schoolName = schoolName;
}
public String getClassName() {
    return className;
}
public void setClassName(String className) {
    this.className = className;
}
public String getName() {
    return name;
}
public void setName(String name) {
    this.name = name;
}
public String getCode() {
    return code;
}
public void setCode(String code) {
    this.code = code;
}
public String getSex() {
    return sex;
}
public void setSex(String sex) {
    this.sex = sex;
}
public String getBirthday() {
    return birthday;
}
public void setBirthday(String birthday) {
    this.birthday = birthday;
}
public String getAddress() {
    return address;
}
public void setAddress(String address) {
    this.address = address;
}

}

public class Student extends School{
public Student(){
super();
}
public Student(String schoolName, String className, String name, String code, String sex, String birthday,
String address){
super(schoolName,className, name, code, sex, birthday,
address);
}
@Override
public String toString() {
return "学校名称:"+this.getSchoolName()+"，"+"班级名称"+this.getClassName()+"，"
+"学生姓名"+this.getName()+"，"+"学号："+this.getCode()+"，"
+"性别："+this.getSex()+"，"+"出生年月："+this.getBirthday()+","
+"家庭住址："+this.getAddress();
}

}

public class Teacher extends School{
public Teacher(){
super();
}
public Teacher(String schoolName, String className, String name, String code, String sex, String birthday,
String address){
super(schoolName,className, name, code, sex, birthday,
address);
}
@Override
public String toString() {
return "学校名称:"+this.getSchoolName()+"，"+"班级名称"+this.getClassName()+"，"
+"教师姓名"+this.getName()+"，"+"教师工号："+this.getCode()+"，"
+"性别："+this.getSex()+"，"+"出生年月："+this.getBirthday()+","
+"家庭住址："+this.getAddress();
}

}

public class Test {
public static void main(String[] args) {
School[] s = new School[4];
s[0]= new Student("重庆大学","计算机二班","王刚","951034","男","1975-07-21","上海浦东新区");
s[1]= new Student("重庆大学","计算机二班","谢娜","951034","女","1976-07-21","北京海淀区");
s[2]= new Teacher("四川大学","计算机二班","赵敏","951034","女","1975-07-21","上海浦东新区");
s[3]= new Teacher("四川大学","计算机二班","赵日天","951034","男","1975-07-21","上海浦东新区");
for(School temp : s){
System.out.println(temp);
}
}

}

我帮你优化了一下你的程序，你可以试着看看我们两个的程序有什么不一样。都做到这地步了你忍心不采纳吗？

这是一个名为Student的类，接口了School
class Student implements School {
private String schoolname;
private String classname;
private String studentname;
private String studentcode;
private String studentsex;
private String studentbirthday;
private String familyaddress;
public void setschoolname (String schoolname){
this.schoolname=schoolname;
}
public void setclassname (String classname){
this.classname=classname;
}
public void setname (String studentname){
this.studentname=studentname;
}
public void setcode (String studentcode){
this.studentcode=studentcode;
}
public void setsex (String studentsex){
this.studentsex=studentsex;
}
public void setbirthday (String studentbirthday){
this.studentbirthday=studentbirthday;
}
public void setfamilyaddress (String familyaddress){
this.familyaddress=familyaddress;
}
public String getschoolname (){
return schoolname;
}
public String getclassname (){
return classname;
}
public String getname (){
return studentname;
}
public String getcode (){
return studentcode;
}
public String getsex (){
return studentsex;
}
public String getbirthday (){
return studentbirthday;
}
public String getfamilyaddress (){
return familyaddress;
}
public String toString (){
String infor="学校名称:"+schoolname+"，"+"班级名称"+classname+"，"+"，"
+"学生姓名"+studentname+"，"+"，"+"学号："+studentcode+"，"+"，"
+"性别："+studentsex+"，"+"出生年月："+studentbirthday+","
+"家庭住址："+familyaddress;
return infor;
}
}

这是一个名为Teacher的类，接口了School
class Teacher implements School{
private String schoolname;
private String classname;
private String teachername;
private String teachercode;
private String teachersex;
private String teacherbirthday;
private String familyaddress;
public void setschoolname (String schoolname){
this.schoolname=schoolname;
}
public void setclassname (String classname){
this.classname=classname;
}
public void setname (String teachername){
this.teachername=teachername;
}
public void setcode (String teachercode){
this.teachercode=teachercode;
}
public void setsex (String teachersex){
this.teachersex=teachersex;
}
public void setbirthday (String teacherbirthday){
this.teacherbirthday=teacherbirthday;
}
public void setfamilyaddress (String familyaddress){
this.familyaddress=familyaddress;
}
public String getschoolname (){
return schoolname;
}
public String getclassname (){
return classname;
}
public String getname (){
return teachername;
}
public String getsex (){
return teachersex;
}
public String getbirthday (){
return teacherbirthday;
}
public String getfamilyaddress (){
return familyaddress;
}
public String toString (){
String infor="学校名称："+schoolname+"，"+"班级名称："+classname+"，"
+"教师姓名："+teachername+"，"+"教师工号："+teachercode+"，"
+"性别："+teachersex+"，"+"出生年月："+teacherbirthday+"，"
+"家庭住址："+familyaddress;
return infor;
}
public String getcode() {
// TODO Auto-generated method stub
return null;
}

}

全部程序就是上面这些，问题是我创的类StudentTest无法执行，可我没发现错误啊

这是一个接口
interface School {
void setschoolname (String schoolname);
void setclassname (String schoolclassname);
void setname (String name);
void setcode (String code);
void setsex (String sex);
void setbirthday (String birthday);
void setfamilyaddress (String familyaddress);
String getschoolname ();
String getclassname ();
String getname ();
String getcode ();
String getsex ();
String getbirthday ();
String getfamilyaddress ();
}

接口中的方法是不是和继承的类中getset方法相同？

可以执行啊。还有啰嗦一句，驼峰命名！驼峰命名！驼峰命名！

System.out.println (st1.toString ());
System.out.println (st2.toString ());
System.out.println (te1.toString ());
System.out.println (te2.toString ());，你的对象能.toString()?