二维数组赋值有关问题

二维数组赋值问题
我现在有一个集合List<Book>;里边有两个Book,

Java code

public class Book {    private String author;    private String bookName;    private int bookPrice;}

我现在想。从List<Book> 中取出每一个属性放到一个二维数组中。
  public String[][] child= {  
{ "author1", "bookName1", "bookPrice1"},  
{ "author2", "bookName2", "bookPrice2"},  
{ "author3", "bookName3", "bookPrice3"}
}; 
需要怎么处理。

[解决办法]
List<Book> books = new ArrayList<Book>();

Book book1 = new Book();
book1.setAuthor("aa");
book1.setBookName("aa");
book1.setBookPrice(11);
books.add(book1);

Book book2 = new Book();
book2.setAuthor("bb");
book2.setBookName("bb");
book2.setBookPrice(22);
books.add(book2);

String[][] child= new String[books.size()][3];
for (int i = 0; i < books.size(); i++) {
Book book = books.get(i);
child[i][0] = book.getAuthor();
child[i][1] = book.getBookName();
child[i][2] = book.getBookPrice() + "";
}

for (int i = 0; i < child.length; i++) {
for (int j = 0; j < child[0].length; j++) {
System.out.print(child[i][j] + "===");
}
System.out.println();
}

结果
aa===aa===11===
bb===bb===22===
[解决办法]
public String[][] abcd(List<Book> b){
int length=b.size();
String[][] a=new String[length][3];
for(int i=0;i<length;i++){
Book temp=b.get(i);
a[i][0] = temp.getAuthor();
a[i][1] = temp.getBookName();
a[i][2] = ""+temp.getBookPrice();
}
return a;
}
[解决办法]

Java code

import java.util.List;import java.util.ArrayList;class Book{    private String author;    private String bookName;    private int bookPrice;    public Book(String author,String bookName,int bookPrice)    {        this.author=author;        this.bookName=bookName;        this.bookPrice=bookPrice;    }    public String getAuthor()    {        return this.author;    }    public String getBookName()    {        return this.bookName;    }    public int getBookPrice()    {        return this.bookPrice;    }}public class BookTest{    public static void main(String[] args)    {        List<Book> list=new ArrayList<Book>();        list.add(new Book("张三","书名1",100));        list.add(new Book("李四","书名2",110));        list.add(new Book("王五","书名3",120));                String[][] child=new String[list.size()][3];                for(int i=0;i<child.length;i++)        {            for(int j=0;j<3;j++)            {                child[j][0]=list.get(j).getAuthor();                child[j][1]=list.get(j).getBookName();                child[j][2]=String.valueOf(list.get(j).getBookPrice());            }        }                for(String[] test:child)            for(String s:test)                System.out.print(s+" ");    }}
[解决办法]
for (int i = 0; i < books.size(); i++) {
Book book = books.get(i);
child[i][0] = book.getAuthor();
child[i][1] = book.getBookName();
child[i][2] = book.getBookPrice() + "";
}

对的，主要就是这个for循环。 

 

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