SpringBoot电商项目进阶Day4

SpringBoot电商项目进阶

运用Excel批量添加商品，并且学习了图片的处理，包括缩放、旋转，添加水印等等。

package com.imooc.mall.controller;

import com.github.pagehelper.PageInfo;
import com.imooc.mall.Service.ProductService;
import com.imooc.mall.common.ApiRestResponse;
import com.imooc.mall.common.Constant;
import com.imooc.mall.exception.ImoocMallException;
import com.imooc.mall.exception.ImoocMallExceptionEnum;
import com.imooc.mall.model.pojo.Product;
import com.imooc.mall.model.request.AddProductReq;
import com.imooc.mall.model.request.UpdateProductReq;
import io.swagger.annotations.ApiOperation;
import net.coobird.thumbnailator.Thumbnails;
import net.coobird.thumbnailator.geometry.Positions;
import org.springframework.beans.BeanUtils;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.*;
import org.springframework.web.multipart.MultipartFile;

import javax.imageio.ImageIO;
import javax.servlet.http.HttpServletRequest;
import javax.validation.Valid;
import java.io.File;
import java.io.IOException;
import java.net.URI;
import java.net.URISyntaxException;
import java.util.UUID;

/**
 * 描述：   后台商品管理Controller
 */
@RestController
public class ProductAdminController {
    @Autowired
    ProductService productService;
    @PostMapping("/admin/product/add")
    public ApiRestResponse addProduct(@Valid @RequestBody AddProductReq addProductReq) {
        productService.add(addProductReq);
        return ApiRestResponse.success();
    }

    @PostMapping("/admin/upload/file")
    public ApiRestResponse upload(HttpServletRequest httpServletRequest, @RequestParam("file") MultipartFile file) {
        String fileName = file.getOriginalFilename();
        String suffixName = fileName.substring(fileName.lastIndexOf("."));
        //生成文件名称UUID
        UUID uuid = UUID.randomUUID();
        String newFileName = uuid.toString() + suffixName;
        //创建文件
        File fileDirectory = new File(Constant.FILE_UPLOAD_DIR);
        File destFile = new File(Constant.FILE_UPLOAD_DIR + newFileName);
        createFile(file, fileDirectory, destFile);
        try {
            return ApiRestResponse.success(getHost(new URI(httpServletRequest.getRequestURL() + "")) + "/images/" + newFileName);
        } catch (URISyntaxException e) {
            return ApiRestResponse.error(ImoocMallExceptionEnum.UPLOAD_FAILED);
        }
    }

    private URI getHost(URI uri) {
        URI effectiveURI;
        try {
            effectiveURI = new URI(uri.getScheme(), uri.getUserInfo(), uri.getHost(), uri.getPort(), null, null, null);
        } catch (URISyntaxException e) {
            effectiveURI=null;
        }
        return effectiveURI;
    }
    @ApiOperation("后台更新商品")
    @PostMapping("/admin/product/update")
    public ApiRestResponse updateProduct(@Valid @RequestBody UpdateProductReq updateProductReq) {
        Product product = new Product();
        BeanUtils.copyProperties(updateProductReq, product);
        productService.update(product);
        return ApiRestResponse.success();
    }
    @ApiOperation("后台删除商品")
    @PostMapping("/admin/product/delete")
    public ApiRestResponse deleteProduct(@RequestParam Integer id) {
        productService.delete(id);
        return ApiRestResponse.success();
    }
    @ApiOperation("后台批量上下架接口")
    @PostMapping("/admin/product/batchUpdateSellStatus")
    public ApiRestResponse batchUpdateSellStatus(@RequestParam Integer[] ids,@RequestParam Integer sellStatus) {
        productService.batchUpdateSellStatus(ids, sellStatus);
        return ApiRestResponse.success();
    }
    @ApiOperation("后台商品列表接口")
    @GetMapping("/admin/product/list")
    public ApiRestResponse list(@RequestParam Integer pageNum,@RequestParam Integer pageSize) {
        PageInfo pageInfo = productService.listForAdmin(pageNum, pageSize);
        return ApiRestResponse.success(pageInfo);
    }
    @ApiOperation("后台批量上传商品接口")
    @PostMapping("/admin/upload/product")
    public ApiRestResponse uploadProduct(@RequestParam("file") MultipartFile multipartFile) throws IOException {
        String fileName = multipartFile.getOriginalFilename();
        String suffixName = fileName.substring(fileName.lastIndexOf("."));
        UUID uuid = UUID.randomUUID();
        String newFileName = uuid.toString() + suffixName;
        //创建文件
        File fileDirectory = new File(Constant.FILE_UPLOAD_DIR);
        File destFile = new File(Constant.FILE_UPLOAD_DIR + newFileName);
        createFile(multipartFile, fileDirectory, destFile);
        productService.addProductByExcel(destFile);
        return ApiRestResponse.success();
    }
    @PostMapping("/admin/upload/image")
    public ApiRestResponse uploadImage(HttpServletRequest httpServletRequest, @RequestParam("file") MultipartFile file) throws IOException {
        String fileName = file.getOriginalFilename();
        String suffixName = fileName.substring(fileName.lastIndexOf("."));
        //生成文件名称UUID
        UUID uuid = UUID.randomUUID();
        String newFileName = uuid.toString() + suffixName;
        //创建文件
        File fileDirectory = new File(Constant.FILE_UPLOAD_DIR);
        File destFile = new File(Constant.FILE_UPLOAD_DIR + newFileName);
        createFile(file, fileDirectory, destFile);
        Thumbnails.of(destFile).size(Constant.IMAGE_SIZE, Constant.IMAGE_SIZE).watermark(Positions.BOTTOM_RIGHT, ImageIO.read(new File(Constant.FILE_UPLOAD_DIR + Constant.WATER_MARK_JPG)), Constant.IMAGE_OPACITY).toFile(new File(Constant.FILE_UPLOAD_DIR + newFileName));
        try {
            return ApiRestResponse.success(getHost(new URI(httpServletRequest.getRequestURL() + "")) + "/images/" + newFileName);
        } catch (URISyntaxException e) {
            return ApiRestResponse.error(ImoocMallExceptionEnum.UPLOAD_FAILED);
        }
    }

    private void createFile(@RequestParam("file") MultipartFile file, File fileDirectory, File destFile) {
        if (!fileDirectory.exists()) {
            if (!fileDirectory.mkdir()) {
                throw new ImoocMallException(ImoocMallExceptionEnum.MKDIR_FAILED);
            }
        }
        try {
            file.transferTo(destFile);
        } catch (IOException e) {
            e.printStackTrace();
        }
    }
}

解决leetcode上关于线段树的两个问题

Leetcode307

public class NumArray4 {
    private SegmentTree<Integer> segmentTree;
    public NumArray4(int[] nums) {
        Integer[] data = new Integer[nums.length];
        for (int i = 0; i < nums.length; i++) {
            data[i] = nums[i];
        }
        segmentTree = new SegmentTree<>(data, (a, b) -> a + b);
    }

    public void update(int index, int val) {
        if (segmentTree == null) {
            throw new IllegalArgumentException("Segment Tree is null");
        }
        segmentTree.set(index, val);
    }
    public int sumRange(int left, int right) {
        if (segmentTree == null) {
            throw new IllegalArgumentException("Segment tree is null");
        }
        return segmentTree.query(left, right);
    }
}

leetcode303

public class NumArray {
    private SegmentTree<Integer> segmentTree;
    public NumArray(int[] nums) {
        if (nums.length > 0) {
            Integer[] data = new Integer[nums.length];
            for (int i = 0; i < nums.length; i++) {
                data[i] = nums[i];
            }
            segmentTree = new SegmentTree<>(data, (a, b) -> a + b);
        }
    }

    public int sumRange(int left, int right) {
        if (segmentTree == null) {
            throw new IllegalArgumentException("Segment tree is null");
        }
        return segmentTree.query(left, right);
    }
}

完成线段树的更新操作

public class SegmentTree<E> {
    private E[] tree;
    private E[] data;
    private Merger<E> merger;

    public SegmentTree(E[] arr, Merger<E> merger) {
        this.merger = merger;
        data = (E[]) new Object[arr.length];
        for (int i = 0; i < arr.length; i++) {
            data[i] = arr[i];
        }
        tree = (E[]) new Object[4 * arr.length];
        buildSegmentTree(0, 0, data.length - 1);
    }
    //在treeIndex的位置创建表示区间[l...r]的线段树
    private void buildSegmentTree(int treeIndex, int l, int r) {
        if (l == r) {
            tree[treeIndex] = data[l];
            return;
        }
        int leftTreeIndex = leftChild(treeIndex);
        int rightTreeIndex = rightChild(treeIndex);
        int mid = l + (r - l) / 2;
        buildSegmentTree(leftTreeIndex, l, mid);
        buildSegmentTree(rightTreeIndex, mid + 1, r);
        tree[treeIndex] = merger.merge(tree[leftTreeIndex] , tree[rightTreeIndex]);
    }

    public int getSize() {
        return data.length;
    }
    public E get(int index) {
        if (index < 0 || index >= data.length) {
            throw new IllegalArgumentException("Index is illegal.");
        }
        return data[index];
    }
    //返回完全二叉树的数组表示中，一个索引所表示的元素的左孩子结点的索引
    private int leftChild(int index) {
        return 2 * index + 1;
    }
    //返回完全二叉树的数组表示中，一个索引所表示的元素的右孩子结点的索引
    private int rightChild(int index) {
        return 2 * index + 2;
    }
    //返回区间[queryL,queryR]的值
    public E query(int queryL, int queryR) {
        if (queryL < 0 || queryL >= data.length
                || queryR < 0 || queryR >= data.length || queryL > queryR) {
            throw new IllegalArgumentException("Index is illegal.");
        }
        return query(0, 0, data.length - 1, queryL,  queryR);
    }
    //在以treeID为根的线段树中[l...r]的范围里，搜索区间[queryL...queryR]的值
    private E query(int treeIndex, int l, int r, int queryL, int queryR) {
        if (l == queryL && r == queryR) {
            return tree[treeIndex];
        }
        int mid = l + (r - l) / 2;
        int leftTreeIndex = leftChild(treeIndex);
        int rightTreeIndex = rightChild(treeIndex);
        if (queryL >= mid + 1) {
            return query(rightTreeIndex, mid + 1, r, queryL, queryR);
        } else if (queryR <= mid) {
            return query(leftTreeIndex, l, mid, queryL, queryR);
        }
        E leftResult = query(leftTreeIndex, l, mid, queryL, mid);
        E rightResult = query(rightTreeIndex, mid + 1, r, mid + 1, queryR);
        return merger.merge(leftResult, rightResult);
    }

    //将index位置的值，更新为e
    public void set(int index, E e) {
        if (index < 0 || index >= data.length) {
            throw new IllegalArgumentException("Index is illegal");
        }
        data[index] = e;
        set(0, 0, data.length - 1, index, e);
    }

    //在以treeIndex为根的线段树中更新index的值为e
    public void set(int treeIndex, int l, int r, int index, E e) {
        if (l == r) {
            tree[treeIndex] = e;
            return;
        }
        int mid = l + (r - l) / 2;
        int leftTreeIndex = leftChild(treeIndex);
        int rightTreeIndex = rightChild(treeIndex);
        if (index >= mid + 1) {
            set(rightTreeIndex, mid + 1, r, index, e);
        } else {
            set(leftTreeIndex, l, mid, index, e);
        }
        tree[treeIndex] = merger.merge(tree[leftTreeIndex], tree[rightTreeIndex]);
    }
    @Override
    public String toString() {
        StringBuilder res = new StringBuilder();
        res.append('[');
        for (int i = 0; i < tree.length; i++) {
            if (tree[i] != null) {
                res.append(tree[i]);
            } else {
                res.append("null");
            }
            if (i != tree.length - 1) {
                res.append(", ");
            }
        }
        res.append(']');
        return res.toString();
    }
}