import java.util.Scanner;
public class Test{
public static void main (String[]args){
       String book[] = new String[]{a,c,d,s,f};
       String newbook[] = (book.length+1);
       int index = book.length; //储存输入的新书名的位置
       for (int i = 0;i<book.length;i++){ //复制数组
              newbook[i]=book[i];
              }
       for (int i =0;i<book.length;i++){ //输出原数组
              System.out.print(book[i]+"");
              }
       Scanner input = new Scanner (System.in);
       System.out.println ("请输入新书的名称(英文):")
       String bookname = input.next();
       for (int i = book.length-1;i>=0;i--){ //查找新书名称所在的位置
            if (book[i].compareToIgnoreCase(bookname)>0){ //通过比较得出新书名称的合适位置
                  index = i ;
                  break;
              }
           }
       newbook[index]=bookname;
       for ( int i = book.length-1;i>index;i-- ){ //让index后的所有变量后退一位
             newbook[i]=newbook[i-1];
              }
       for (int c=0;c<newbook.length;c++){ //输出新数组
              System.out.print(newbook[c]+"")
            }
     }
}

String book[] = {"","","","",""};
           String newbook[] = new String[book.length+1];
           int index = book.length; //储存输入的新书名的位置
           for (int i = 0;i<book.length;i++){ //复制数组
                  newbook[i]=book[i];
                  }
           for (int i =0;i<book.length;i++){ //输出原数组
                  System.out.print(book[i]+"");
                  }
           Scanner input = new Scanner (System.in);
           System.out.println ("请输入新书的名称(英文):");
           String bookname = input.next();
           for (int i = book.length-1;i>=0;i--){ //查找新书名称所在的位置
                if (book[i].compareToIgnoreCase(bookname)>0){ //通过比较得出新书名称的合适位置
                      index = i ;
                      break;
                  }
               }
           newbook[index]=bookname;
           for ( int i = book.length-1;i>index;i-- ){ //让index后的所有变量后退一位
                 newbook[i]=newbook[i-1];
                  }
           for (int c=0;c<newbook.length;c++){ //输出新数组
                  System.out.print(newbook[c]+"");
                }
         }

------解决方案--------------------
确实 是要改的    改了后  输出结果为：
D:\>java Test
请输入新书的名称(英文):
cary
cary