Bài 7: Springboot- Thymeleaf: Phân trang trình bày danh sách đối tượn

<dependency>
		    <groupId>org.springframework.data</groupId>
		    <artifactId>spring-data-commons</artifactId>
		    <version>2.3.2.RELEASE</version>
</dependency>

package thomc.DisplayListObjectPagination.services;

import org.springframework.stereotype.Service;
import thomc.DisplayListObjectPagination.models.SinhVien;
import org.springframework.data.domain.Page;
import org.springframework.data.domain.PageImpl;
import org.springframework.data.domain.PageRequest;
import org.springframework.data.domain.Pageable;
@Service
public interface SinhvienService {
	public Page<SinhVien> findPaginated(Pageable pageable);
}

package thomc.DisplayListObjectPagination.services;

import org.springframework.stereotype.Service;

import thomc.DisplayListObjectPagination.models.SinhVien;

import java.util.ArrayList;
import java.util.Collections;
import java.util.List;

import org.springframework.data.domain.Page;
import org.springframework.data.domain.PageImpl;
import org.springframework.data.domain.PageRequest;
import org.springframework.data.domain.Pageable;
@Service
public class SinhVienServiceImpl implements SinhvienService {
	// Ta hard-code dữ liệu tại đây  để tiện demo------ 
	static List<SinhVien> dsSinhVien=  new ArrayList<SinhVien>();
	static {
		dsSinhVien.add(new SinhVien("0001", "Mai Cường Thọ"));
		dsSinhVien.add(new SinhVien("0002", "Trần Văn Long"));
		dsSinhVien.add(new SinhVien("0003", "Phạm Thị Hoa"));
		dsSinhVien.add(new SinhVien("0004", "Lê Hùng Cương"));
		dsSinhVien.add(new SinhVien("0005", "Phan Minh ANh"));
		dsSinhVien.add(new SinhVien("0006", "Lê Thị Hoa"));
		dsSinhVien.add(new SinhVien("0007", "Bụi Văn Cúc"));
		dsSinhVien.add(new SinhVien("0008", "Lê Hồng Phong"));
		dsSinhVien.add(new SinhVien("0009", "Lệ Chu Lai"));
		dsSinhVien.add(new SinhVien("0010", "Nguyễn Hùng Cường"));
		dsSinhVien.add(new SinhVien("0011", "Lê Bá Vương"));
		dsSinhVien.add(new SinhVien("0012", "Trần Thống Nhất"));
	}
	//----------hết phần hard-code dữ liệu ---------------------
	@Override
	public Page<SinhVien> findPaginated(Pageable pageable) {
		int pageSize = pageable.getPageSize();
        int currentPage = pageable.getPageNumber();
        int startItem = currentPage * pageSize;
        List<SinhVien> list;

        if (dsSinhVien.size() < startItem) {
            list = Collections.emptyList();
        } else {
            int toIndex = Math.min(startItem + pageSize, dsSinhVien.size());
            list = dsSinhVien.subList(startItem, toIndex);
        }
        Page<SinhVien> sinhvienPage = new PageImpl<SinhVien>(list, PageRequest.of(currentPage, pageSize), dsSinhVien.size());
        return sinhvienPage;
	}

}

package thomc.DisplayListObjectPagination.controllers;

import java.util.ArrayList;
import java.util.List;
import java.util.Optional;
import java.util.stream.Collectors;
import java.util.stream.IntStream;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.data.domain.Page;
import org.springframework.data.domain.PageRequest;
import org.springframework.stereotype.Controller;
import org.springframework.ui.Model;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.RequestParam;

import thomc.DisplayListObjectPagination.models.SinhVien;
import thomc.DisplayListObjectPagination.services.SinhvienService;
@Controller
public class SinhVienController {
	 @Autowired
	 private SinhvienService svService;
	 
	@GetMapping("/danhsachSV")
	public String listStudent(Model model,  
								@RequestParam("page") Optional<Integer> page,
								@RequestParam("size") Optional<Integer> size) {
		final int currentPage = page.orElse(1);
        final int pageSize = size.orElse(5);
        Page<SinhVien> svPage = svService.findPaginated(PageRequest.of(currentPage - 1, pageSize));
		model.addAttribute("dsSV", svPage);
		
		int totalPages = svPage.getTotalPages();
        if (totalPages > 0) {
            List<Integer> pageNumbers = IntStream.rangeClosed(1, totalPages)
                .boxed()
                .collect(Collectors.toList());
            model.addAttribute("pageNumbers", pageNumbers);
        }
        return "sinhvien_getAll_Paged";
	}
}

<!DOCTYPE html>
<html xmlns:th="http://www.thymeleaf.org">
<head>
<title>Danh sách sinh viên</title>
</head>
<body>
	<h1>Danh sách sinh viên</h1>
	<table border="1">
        <thead>
            <tr>
                <th> Mã số sinh viên </th>
                <th> Họ và tên </th>
            </tr>
        </thead>
        <tbody>
            <tr th:each="sv: ${dsSV}">
                <td th:text="${sv.maSoSV}" />
				<td th:text="${sv.hoVaTen}" />
            </tr>
        </tbody>
    </table>
    <div th:if="${dsSV.totalPages > 0}" th:each="pageNumber : ${pageNumbers}">
        <a th:href="@{/danhsachSV(size=${dsSV.size}, page=${pageNumber})}"
            th:text=${pageNumber}
            th:class="${pageNumber==dsSV.number + 1} ? active"></a>
    </div>
	
	
</body>
</html>