UBLIC "-//mybatis.o
时间: 2024-09-27 07:11:54 浏览: 37
"UBLIC "-//mybatis.org//DTD Mapper 3.0//EN"" 这段字符串是一个XML文档声明(Document Type Declaration, DTD),用于指定XML文件的结构和内容所遵循的规范。它表明该文件是基于MyBatis组织(mybatis.org)发布的Mapper 3.0版本的定义。MyBatis是一个流行的Java持久层框架,用于将数据库操作映射到Java对象上,这里的DTD定义了Mapper XML配置文件的结构,如SQL查询、结果映射等元素的布局和验证规则。
Mapper XML文件通常包含在Spring Boot项目中,用来配置数据访问层(DAO)与业务逻辑之间的交互。例如:
```xml
<sql id="selectUserById">SELECT * FROM user WHERE id = #{id}</sql>
<mapper namespace="com.example.UserMapper">
<select id="getUserById" resultType="com.example.User">
<include refid="selectUserById"/>
</select>
</mapper>
```
相关问题
注:接口中带 TODO 字样的方法,是视频中没有写的,需要你们自己实现。 写一个BinarySearchTree 来实现 Tree 接口,定义如下: ublic class BinarySearchTree<T extends Comparable<T>> implements Tree<T> { //属性: //1. 指向根节点 private Node<T> root; //2.树中节点的数量 private int size; //TODO 实现接口所有的方法,另外,要实现remove方法,在此类中还要额外提供 findParentNode(T target) 方法和 findMinNodeFromRight(Node<T> target) 方法 }
好的,我明白了。以下是实现 BinaryTree 接口的 BinarySearchTree 类的代码:
```
public class BinarySearchTree<T extends Comparable<T>> implements Tree<T> {
//属性:
//1. 指向根节点
private Node<T> root;
//2.树中节点的数量
private int size;
//构造函数
public BinarySearchTree() {
this.root = null;
this.size = 0;
}
//节点类
private static class Node<T> {
T value;
Node<T> left;
Node<T> right;
public Node(T value) {
this.value = value;
this.left = null;
this.right = null;
}
}
//实现接口所有的方法
@Override
public boolean insert(T value) {
if (value == null) {
return false;
}
if (root == null) {
root = new Node<T>(value);
size++;
return true;
}
Node<T> parent = findParentNode(value);
int cmp = value.compareTo(parent.value);
if (cmp == 0) {
return false;
} else if (cmp < 0) {
parent.left = new Node<T>(value);
} else {
parent.right = new Node<T>(value);
}
size++;
return true;
}
@Override
public boolean remove(T value) {
if (root == null || value == null) {
return false;
}
Node<T> parent = findParentNode(value);
Node<T> current = null;
if (parent == null) {
current = root;
} else if (parent.left != null && parent.left.value.compareTo(value) == 0) {
current = parent.left;
} else if (parent.right != null && parent.right.value.compareTo(value) == 0) {
current = parent.right;
} else {
return false;
}
if (current.left == null && current.right == null) {
if (parent == null) {
root = null;
} else if (parent.left == current) {
parent.left = null;
} else {
parent.right = null;
}
} else if (current.left == null) {
if (parent == null) {
root = current.right;
} else if (parent.left == current) {
parent.left = current.right;
} else {
parent.right = current.right;
}
} else if (current.right == null) {
if (parent == null) {
root = current.left;
} else if (parent.left == current) {
parent.left = current.left;
} else {
parent.right = current.left;
}
} else {
Node<T> minFromRight = findMinNodeFromRight(current);
remove(minFromRight.value);
current.value = minFromRight.value;
}
size--;
return true;
}
@Override
public boolean contains(T value) {
Node<T> current = root;
while (current != null) {
int cmp = value.compareTo(current.value);
if (cmp == 0) {
return true;
} else if (cmp < 0) {
current = current.left;
} else {
current = current.right;
}
}
return false;
}
@Override
public int size() {
return size;
}
@Override
public void clear() {
root = null;
size = 0;
}
//找到待插入节点的父节点
private Node<T> findParentNode(T value) {
Node<T> parent = null;
Node<T> current = root;
while (current != null) {
int cmp = value.compareTo(current.value);
if (cmp == 0) {
return current;
} else if (cmp < 0) {
parent = current;
current = current.left;
} else {
parent = current;
current = current.right;
}
}
return parent;
}
//找到右子树中的最小节点
private Node<T> findMinNodeFromRight(Node<T> current) {
Node<T> minNode = current.right;
while (minNode.left != null) {
minNode = minNode.left;
}
return minNode;
}
}
```
#include <iostream>#include <string>using namespace std;class Entry {public: virtual void add() = 0; virtual void remove() = 0; virtual void search() = 0; virtual void modify() = 0;};class GeneralEntry : public Entry {public: void add() override { // 添加一般条目的实现 } void remove() override { // 删除一般条目的实现 } void search() override { // 查找一般条目的实现 } void modify() override { // 修改一般条目的实现 }};class FriendEntry : public Entry {public: void add() override { // 添加朋友条目的实现 } void remove() override { // 删除朋友条目的实现 } void search() override { // 查找朋友条目的实现 } void modify() override { // 修改朋友条目的实现 } void viewCommonFriends() { // 查看共同好友的实现 }};class AddressBook {private: int totalEntries;Entry* entryries[100];p ublic: AddressBook() { totalEntries = 0; } void addEntry(Entry* entry) { entries[totalEntries++] = entry; } void removeEntry(int index) { // 删除通讯录条目的实现 } void searchEntry(string name) { // 查找通讯录条目的实现 } void modifyEntry(int index) { // 修改通讯录条目的实现 } void displayEntries() { // 输出通讯录的实现 }};int main() { AddressBook book;一般条目 g条目;朋友条目 f条目;book.addEntry(&gEntry);book.addEntry(&fEntry);// ...返回 0;},对上面代码进行完善并写出代码
上面的代码是一个简单的通讯录程序的实现,我们可以进行以下完善:
1. 添加更多的通讯录条目类型
可以添加更多的通讯录条目类型,如家庭条目、工作条目等等,以满足不同用户的需求。需要添加对应的类,并实现相应的函数。
2. 完善通讯录条目的属性
可以添加更多的属性,如电子邮件、地址等等。需要在对应的类中添加相应的属性,并实现修改和访问函数。
3. 实现更多的通讯录操作
可以添加更多的操作,如导入、导出、备份等等,以提高程序的实用性。需要在AddressBook类中添加相应的函数。
4. 实现用户界面
可以实现一个用户界面,使用户操作更加直观、方便。需要实现一个交互式界面,并调用AddressBook类的相应函数。
下面是完善后的代码:
``` cpp
#include <iostream>
#include <string>
#include <vector>
using namespace std;
class Entry {
public:
virtual void add() = 0;
virtual void remove() = 0;
virtual void search() = 0;
virtual void modify() = 0;
};
class GeneralEntry : public Entry {
private:
string name;
string phoneNumber;
string email;
string address;
public:
void add() override {
// 添加一般条目的实现
cout << "请输入姓名:";
cin >> name;
cout << "请输入电话号码:";
cin >> phoneNumber;
cout << "请输入电子邮件:";
cin >> email;
cout << "请输入地址:";
cin >> address;
}
void remove() override {
// 删除一般条目的实现
name = "";
phoneNumber = "";
email = "";
address = "";
}
void search() override {
// 查找一般条目的实现
cout << "姓名:" << name << endl;
cout << "电话号码:" << phoneNumber << endl;
cout << "电子邮件:" << email << endl;
cout << "地址:" << address << endl;
}
void modify() override {
// 修改一般条目的实现
cout << "请输入姓名:";
cin >> name;
cout << "请输入电话号码:";
cin >> phoneNumber;
cout << "请输入电子邮件:";
cin >> email;
cout << "请输入地址:";
cin >> address;
}
};
class FriendEntry : public Entry {
private:
string name;
string phoneNumber;
string email;
string address;
vector<string> commonFriends;
public:
void add() override {
// 添加朋友条目的实现
cout << "请输入姓名:";
cin >> name;
cout << "请输入电话号码:";
cin >> phoneNumber;
cout << "请输入电子邮件:";
cin >> email;
cout << "请输入地址:";
cin >> address;
cout << "请输入共同好友(以空格分隔):";
string friendName;
while (cin >> friendName) {
commonFriends.push_back(friendName);
}
}
void remove() override {
// 删除朋友条目的实现
name = "";
phoneNumber = "";
email = "";
address = "";
commonFriends.clear();
}
void search() override {
// 查找朋友条目的实现
cout << "姓名:" << name << endl;
cout << "电话号码:" << phoneNumber << endl;
cout << "电子邮件:" << email << endl;
cout << "地址:" << address << endl;
cout << "共同好友:";
for (auto friendName : commonFriends) {
cout << friendName << " ";
}
cout << endl;
}
void modify() override {
// 修改朋友条目的实现
cout << "请输入姓名:";
cin >> name;
cout << "请输入电话号码:";
cin >> phoneNumber;
cout << "请输入电子邮件:";
cin >> email;
cout << "请输入地址:";
cin >> address;
cout << "请输入共同好友(以空格分隔):";
string friendName;
vector<string> newCommonFriends;
while (cin >> friendName) {
newCommonFriends.push_back(friendName);
}
commonFriends = newCommonFriends;
}
void viewCommonFriends() {
// 查看共同好友的实现
cout << "共同好友:";
for (auto friendName : commonFriends) {
cout << friendName << " ";
}
cout << endl;
}
};
class AddressBook {
private:
vector<Entry*> entries;
public:
void addEntry(Entry* entry) {
entries.push_back(entry);
}
void removeEntry(int index) {
// 删除通讯录条目的实现
entries.erase(entries.begin() + index);
}
void searchEntry(string name) {
// 查找通讯录条目的实现
for (int i = 0; i < entries.size(); i++) {
if (dynamic_cast<GeneralEntry*>(entries[i])) {
GeneralEntry* generalEntry = dynamic_cast<GeneralEntry*>(entries[i]);
if (generalEntry->name == name) {
generalEntry->search();
return;
}
}
else if (dynamic_cast<FriendEntry*>(entries[i])) {
FriendEntry* friendEntry = dynamic_cast<FriendEntry*>(entries[i]);
if (friendEntry->name == name) {
friendEntry->search();
return;
}
}
}
cout << "未找到该条目" << endl;
}
void modifyEntry(int index) {
// 修改通讯录条目的实现
if (dynamic_cast<GeneralEntry*>(entries[index])) {
GeneralEntry* generalEntry = dynamic_cast<GeneralEntry*>(entries[index]);
generalEntry->modify();
}
else if (dynamic_cast<FriendEntry*>(entries[index])) {
FriendEntry* friendEntry = dynamic_cast<FriendEntry*>(entries[index]);
friendEntry->modify();
}
}
void displayEntries() {
// 输出通讯录的实现
for (int i = 0; i < entries.size(); i++) {
cout << "条目 " << i << ":" << endl;
if (dynamic_cast<GeneralEntry*>(entries[i])) {
GeneralEntry* generalEntry = dynamic_cast<GeneralEntry*>(entries[i]);
generalEntry->search();
}
else if (dynamic_cast<FriendEntry*>(entries[i])) {
FriendEntry* friendEntry = dynamic_cast<FriendEntry*>(entries[i]);
friendEntry->search();
}
}
}
};
int main() {
AddressBook book;
GeneralEntry gEntry1;
book.addEntry(&gEntry1);
GeneralEntry gEntry2;
book.addEntry(&gEntry2);
FriendEntry fEntry1;
book.addEntry(&fEntry1);
FriendEntry fEntry2;
book.addEntry(&fEntry2);
cout << "通讯录条目添加完毕" << endl;
while (true) {
cout << "请选择操作:" << endl;
cout << "1. 添加条目" << endl;
cout << "2. 删除条目" << endl;
cout << "3. 查找条目" << endl;
cout << "4. 修改条目" << endl;
cout << "5. 显示所有条目" << endl;
cout << "6. 退出程序" << endl;
int choice;
cin >> choice;
switch (choice) {
case 1:
cout << "请选择条目类型:" << endl;
cout << "1. 一般条目" << endl;
cout << "2. 朋友条目" << endl;
int type;
cin >> type;
if (type == 1) {
GeneralEntry* generalEntry = new GeneralEntry();
generalEntry->add();
book.addEntry(generalEntry);
}
else if (type == 2) {
FriendEntry* friendEntry = new FriendEntry();
friendEntry->add();
book.addEntry(friendEntry);
}
break;
case 2:
cout << "请输入要删除的条目编号:" << endl;
int index;
cin >> index;
book.removeEntry(index);
cout << "条目已删除" << endl;
break;
case 3:
cout << "请输入要查找的条目姓名:" << endl;
string name;
cin >> name;
book.searchEntry(name);
break;
case 4:
cout << "请输入要修改的条目编号:" << endl;
int index2;
cin >> index2;
book.modifyEntry(index2);
cout << "条目已修改" << endl;
break;
case 5:
book.displayEntries();
break;
case 6:
cout << "程序已退出" << endl;
return 0;
default:
cout << "无效操作,请重新输入" << endl;
break;
}
}
}
```
这是一个基本的通讯录程序,支持添加、删除、查找、修改和显示所有条目的功能,支持一般条目和朋友条目两种类型,支持动态添加和删除条目。用户可以通过菜单选择相应的操作,程序会根据用户选择调用相应的函数进行操作。
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