购物车功能设计（一）

分析购物车结构

这里主要以京东的购物车页面为列

从图中可以分析出我们可以建两个实体类：Cart.java和CartItem.java
其中Cart.java中应该至少包含cartItems（购物项）和totalPrice（总计）
CartItem.java实体类中至少包含Product实体类、buyNum、subtotalPrice、cartState等属性

购物车、购物项、商品实体类之间的设计及关系

首先存在一个Product实体类（其中LssgProductClass 为这个实体的商品类别）

package com.lianwei.lssg.entity;

import java.io.Serializable;
import java.math.BigDecimal;
import java.util.Date;

public class LssgProduct implements Serializable {
    
    
    private Integer productId;

    private LssgProductClass lssgProductClass;

    private String productName;

    private Date productUpTime;

    private Date productDownTime;

    private String productPhoto;

    private String smallPhoto;

    private String bigPhoto;

    private BigDecimal productMarketPrice;

    private BigDecimal productMallPrice;

    private Integer productNum;

    private Integer soldNum;

    private BigDecimal productWeight;

    private BigDecimal promotePrice;

    private Date promoteStartDate;

    private Date promoteEndDate;

    private BigDecimal fregiht;

    private Integer isBest;

    private Integer isNew;

    private Integer isHot;

    private Integer isSpecial;

    private Integer isState;

    private String productAddr;

    private String productNotes;

    private String productEffect;

    private static final long serialVersionUID = 1L;

    public Integer getProductId() {
    
    
        return productId;
    }

    public void setProductId(Integer productId) {
    
    
        this.productId = productId;
    }

    public String getProductName() {
    
    
        return productName;
    }

    public void setProductName(String productName) {
    
    
        this.productName = productName;
    }

    public Date getProductUpTime() {
    
    
        return productUpTime;
    }

    public void setProductUpTime(Date productUpTime) {
    
    
        this.productUpTime = productUpTime;
    }

    public Date getProductDownTime() {
    
    
        return productDownTime;
    }

    public void setProductDownTime(Date productDownTime) {
    
    
        this.productDownTime = productDownTime;
    }

    public String getProductPhoto() {
    
    
        return productPhoto;
    }

    public void setProductPhoto(String productPhoto) {
    
    
        this.productPhoto = productPhoto;
    }

    public String getSmallPhoto() {
    
    
        return smallPhoto;
    }

    public void setSmallPhoto(String smallPhoto) {
    
    
        this.smallPhoto = smallPhoto;
    }

    public String getBigPhoto() {
    
    
        return bigPhoto;
    }

    public void setBigPhoto(String bigPhoto) {
    
    
        this.bigPhoto = bigPhoto;
    }

    public BigDecimal getProductMarketPrice() {
    
    
        return productMarketPrice;
    }

    public void setProductMarketPrice(BigDecimal productMarketPrice) {
    
    
        this.productMarketPrice = productMarketPrice;
    }

    public BigDecimal getProductMallPrice() {
    
    
        return productMallPrice;
    }

    public void setProductMallPrice(BigDecimal productMallPrice) {
    
    
        this.productMallPrice = productMallPrice;
    }

    public Integer getProductNum() {
    
    
        return productNum;
    }

    public void setProductNum(Integer productNum) {
    
    
        this.productNum = productNum;
    }

    public Integer getSoldNum() {
    
    
        return soldNum;
    }

    public void setSoldNum(Integer soldNum) {
    
    
        this.soldNum = soldNum;
    }

    public BigDecimal getProductWeight() {
    
    
        return productWeight;
    }

    public void setProductWeight(BigDecimal productWeight) {
    
    
        this.productWeight = productWeight;
    }

    public BigDecimal getPromotePrice() {
    
    
        return promotePrice;
    }

    public void setPromotePrice(BigDecimal promotePrice) {
    
    
        this.promotePrice = promotePrice;
    }

    public Date getPromoteStartDate() {
    
    
        return promoteStartDate;
    }

    public void setPromoteStartDate(Date promoteStartDate) {
    
    
        this.promoteStartDate = promoteStartDate;
    }

    public Date getPromoteEndDate() {
    
    
        return promoteEndDate;
    }

    public void setPromoteEndDate(Date promoteEndDate) {
    
    
        this.promoteEndDate = promoteEndDate;
    }

    public BigDecimal getFregiht() {
    
    
        return fregiht;
    }

    public void setFregiht(BigDecimal fregiht) {
    
    
        this.fregiht = fregiht;
    }

    public Integer getIsBest() {
    
    
        return isBest;
    }

    public void setIsBest(Integer isBest) {
    
    
        this.isBest = isBest;
    }

    public Integer getIsNew() {
    
    
        return isNew;
    }

    public void setIsNew(Integer isNew) {
    
    
        this.isNew = isNew;
    }

    public Integer getIsHot() {
    
    
        return isHot;
    }

    public void setIsHot(Integer isHot) {
    
    
        this.isHot = isHot;
    }

    public Integer getIsSpecial() {
    
    
        return isSpecial;
    }

    public void setIsSpecial(Integer isSpecial) {
    
    
        this.isSpecial = isSpecial;
    }

    public Integer getIsState() {
    
    
        return isState;
    }

    public void setIsState(Integer isState) {
    
    
        this.isState = isState;
    }

    public String getProductAddr() {
    
    
        return productAddr;
    }

    public void setProductAddr(String productAddr) {
    
    
        this.productAddr = productAddr;
    }

    public String getProductNotes() {
    
    
        return productNotes;
    }

    public void setProductNotes(String productNotes) {
    
    
        this.productNotes = productNotes;
    }

    public static long getSerialVersionUID() {
    
    
        return serialVersionUID;
    }

    public LssgProductClass getLssgProductClass() {
    
    
        return lssgProductClass;
    }

    public void setLssgProductClass(LssgProductClass lssgProductClass) {
    
    
        this.lssgProductClass = lssgProductClass;
    }

    public String getProductEffect() {
    
    
        return productEffect;
    }

    public void setProductEffect(String productEffect) {
    
    
        this.productEffect = productEffect;
    }
}

LssgProductClass 实体类

package com.lianwei.lssg.entity;

import java.io.Serializable;

public class LssgProductClass implements Serializable {
    
    
    private Integer productClassId;
    private String productClassName;
    private String productIsShow;
    private String productDescription;

    public Integer getProductClassId() {
    
    
        return productClassId;
    }

    public void setProductClassId(Integer productClassId) {
    
    
        this.productClassId = productClassId;
    }

    public String getProductClassName() {
    
    
        return productClassName;
    }

    public void setProductClassName(String productClassName) {
    
    
        this.productClassName = productClassName;
    }

    public String getProductIsShow() {
    
    
        return productIsShow;
    }

    public void setProductIsShow(String productIsShow) {
    
    
        this.productIsShow = productIsShow;
    }

    public String getProductDescription() {
    
    
        return productDescription;
    }

    public void setProductDescription(String productDescription) {
    
    
        this.productDescription = productDescription;
    }

    @Override
    public String toString() {
    
    
        return "LssgProductClass{" +
                "productClassId=" + productClassId +
                ", productClassName='" + productClassName + '\'' +
                ", productIsShow='" + productIsShow + '\'' +
                ", productDescription='" + productDescription + '\'' +
                '}';
    }
}

从而得到LssgCart实体类（这里以代码实体类名来说明）

/*
  Created by IntelliJ IDEA.
  User: Kalvin
  Date: 2020/5/11
  Time: 22:49
*/
package com.lianwei.lssg.entity;

import java.io.Serializable;
import java.math.BigDecimal;
import java.util.HashMap;
import java.util.Map;

public class LssgCart implements Serializable {
    
    

    private Map<String, LssgCartItem> cartItems = new HashMap<String, LssgCartItem>();

    private BigDecimal totalPrice;

    public Map<String, LssgCartItem> getCartItems() {
    
    
        return cartItems;
    }

    public void setCartItems(Map<String, LssgCartItem> cartItems) {
    
    
        this.cartItems = cartItems;
    }

    public BigDecimal getTotalPrice() {
    
    
        return totalPrice;
    }

    public void setTotalPrice(BigDecimal totalPrice) {
    
    
        this.totalPrice = totalPrice;
    }
}

创建LssgCartItem实体类

/*
  Created by IntelliJ IDEA.
  User: Kalvin
  Date: 2020/5/12
  Time: 10:59
*/
package com.lianwei.lssg.entity;

import java.io.Serializable;
import java.math.BigDecimal;

public class LssgCartItem implements Serializable {
    
    
    private LssgProduct lssgProduct;
    private BigDecimal buyNum;     //购买总重量
    private BigDecimal subtotalPrice;
    private String cartState;   //商品库存状态（无货、有货、补货中）

    public LssgCartItem() {
    
    
    }

    public LssgCartItem(LssgProduct lssgProduct, BigDecimal buyNum, BigDecimal subtotalPrice, String cartState) {
    
    
        this.lssgProduct = lssgProduct;
        this.buyNum = buyNum;
        this.subtotalPrice = subtotalPrice;
        this.cartState = cartState;
    }

    public LssgProduct getLssgProduct() {
    
    
        return lssgProduct;
    }

    public void setLssgProduct(LssgProduct lssgProduct) {
    
    
        this.lssgProduct = lssgProduct;
    }

    public BigDecimal getBuyNum() {
    
    
        return buyNum;
    }

    public void setBuyNum(BigDecimal buyNum) {
    
    
        this.buyNum = buyNum;
    }

    public BigDecimal getSubtotalPrice() {
    
    
        return subtotalPrice;
    }

    public void setSubtotalPrice(BigDecimal subtotalPrice) {
    
    
        this.subtotalPrice = subtotalPrice;
    }

    public String getCartState() {
    
    
        return cartState;
    }

    public void setCartState(String cartState) {
    
    
        this.cartState = cartState;
    }
}

到这我们就完成了购物车实体设计，主要明白购物车、购物项、商品三者之间的关系