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。

------解决方案--------------------
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===
------解决方案--------------------
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;
}
------解决方案--------------------

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+" ");
    }
}

------解决方案--------------------
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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