Question

在Stack Overflow上有类似的问题，但我仍然找不到解决方案。我正在为图书馆创建一个简单的系统信息原型如何让我的程序具有搜索功能？ Library类中的方法应该返回与给定标题，发布者或年份匹配的书籍列表。此外，该方法需要返回一个arraylist。这是我到目前为止所拥有的。

public class Book {

private String title;
private String publisher;
private int year;

public Book(String title, String publisher, int year) {
    this.title = title;
    this.publisher = publisher;
    this.year = year;
}

public String title() {
    return this.title;
}

public String publisher() {
    return this.publisher;
}

public int year() {
    return this.year;
}

public String toString() {
    return this.title + ", " + this.publisher + ", " + this.year;
}

}

import java.util.ArrayList;

public class Library {

private ArrayList<Book> list;

public Library() {
    this.list = new ArrayList<Book>();

}

public void addBook(Book newBook) {

    list.add(newBook);

}

public void printBooks() {
    for (Book boo : this.list) {
        System.out.println(boo);
    }
}

public ArrayList<Book> searchByTitle(String title) {
    ArrayList<Book> found = new ArrayList<Book>

    for (Book title : found) {
        if (title.contains(title.title())) {
            return title;
        }
    }
    return found;

}

public ArrayList<Book> searchByPublisher(String publisher) {
    ArrayList<Book> found = new ArrayList<Book> 

    //similar code to the other ArrayList method

    return found;

}

public ArrayList<Book> searchByYear(String year) {
    ArrayList<Book> found = new ArrayList<Book> 

    //similar code to the other ArrayList method

    return found;

}

}

public class Main {
public static void main(String[] args) {
    Library Library = new Library();

Library.addBook(new Book("Cheese Problems Solved", "Woodhead Publishing", 2007));
Library.addBook(new Book("The Stinky Cheese Man and Other Fairly Stupid Tales",     "Penguin Group", 1992));
Library.addBook(new Book("NHL Hockey", "Stanley Kupp", 1952));
Library.addBook(new Book("Battle Axes", "Tom A. Hawk", 1851));

ArrayList<Book> result = Library.searchByTitle("Cheese");
for (Book Book: result) {
System.out.println(Book);
}

System.out.println("---");
for (Book Book: Library.searchByPublisher("Penguin Group  ")) {
System.out.println(Book);
}

System.out.println("---");
for (Book Book: Library.searchByYear(1851)) {
System.out.println(Book);
}
  }
}

Answer 1

你是正确的方式。只需将找到的书籍添加到结果列表中：

public ArrayList<Book> searchByTitle(String title) {
    ArrayList<Book> found = new ArrayList<Book>();

    for (Book book : found) {
        if (book.title().contains(title)) {
            found.add(book);
        }
    }
    return found;
}

我还纠正了你在代码安宁方面遇到的一些错误。你的其他代码似乎充满了其他错误，我在这里没有解决。您可能想要了解有关Java语法的更多信息。

修改

正如威格尔斯先生指出的那样，你可能想要一个不区分大小写的搜索。请参阅How to check if a String contains another String in a case insensitive manner in Java?。

在系统信息原型中创建搜索功能

1 个答案: