字符串转换和toString()、字符截取charAt()、一次截取多个字符getChars()

class Person{
?String name;
?String sex;
?int???? age;
?Person(String name,String sex,int age){
??this.name = name;
??this.sex?? = sex;
??this.age?? = age;
?}
?public String toString(){
??return "Dimensions are " + name + " by " + sex + " by " + age +".";
?}
}
public class toStringDemo{
?public static void main(String[] args)
?{
??Person ps = new Person("ChenHuajiang","Male",28);? //convert Person to String
??System.out.println(ps);

??String strName = "ShengJiahui";
??System.out.println(strName.charAt(1));? //直接引用单个字符

?//一次截取多个字符的一般形式

// void getChars(int sourceStart, int sourceEnd, char target[] , int targetStart)?

? int intStart = 5;
??int intEnd?? = 11;
??char[] arrName = new char[intEnd - intStart];
??strName.getChars(intStart,intEnd,arrName,0);
??System.out.println(arrName);
?}
}