代码自动生成（二）数据库表字段生成mybaties 映射配置文件**mapper.xml

上一篇写的是根据数据库字段生成java bean，虽然有一些缺陷，但是大家可以根据字的需求进行优化，本篇博客写的是根据数据库表字段生成mybaties 映射配置文件**mapper.xml，之后还会陆续更新mybaties对应的接口。欢迎大家来点评，指出不足之处。

下面试freemarker工具类

import java.io.BufferedWriter;
import java.io.File;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.OutputStreamWriter;
import java.io.PrintWriter;
import java.io.Writer;
import java.util.Locale;
import java.util.Map;

import freemarker.template.Configuration;
import freemarker.template.Template;
import freemarker.template.TemplateException;

public class Freemarker {

/**
* 打印到控制台(测试)
*  @param ftlName
*/
public static void print(String ftlName, Map<String,Object> root, String ftlPath) throws Exception{
try {
Template temp = getTemplate(ftlName, ftlPath);		//通过Template可以将模板文件输出到相应的流
temp.process(root, new PrintWriter(System.out));
} catch (TemplateException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
}

/**
* 输出到输出到文件
* @param ftlName   ftl文件
* @param root		传入的map
* @param outFile	输出后的文件全部路径
* @param filePath	输出前的文件上部路径
*/
public static void printFile(String ftlName, Map<String,Object> root, String outFile, String filePath, String ftlPath) throws Exception{
try {
File file = new File( filePath + outFile);
if(!file.getParentFile().exists()){				//判断有没有父路径，就是判断文件整个路径是否存�?
file.getParentFile().mkdirs();				//不存在就全部创建
}
Writer out = new BufferedWriter(new OutputStreamWriter(new FileOutputStream(file), "utf-8"));
Template template = getTemplate(ftlName, ftlPath);
template.process(root, out);					//模版输出
out.flush();
out.close();
} catch (TemplateException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
}

/**
* 通过文件名加载模�?
* @param ftlName
*/
public static Template getTemplate(String ftlName, String ftlPath) throws Exception{
try {
Configuration cfg = new Configuration();  												//通过Freemaker的Configuration读取相应的ftl
cfg.setEncoding(Locale.CHINA, "utf-8");
cfg.setDirectoryForTemplateLoading(new File(ftlPath));		//设定去哪里读取相应的ftl模板文件
Template temp = cfg.getTemplate(ftlName);												//在模板文件目录中找到名称为name的文�?
return temp;
} catch (IOException e) {
e.printStackTrace();
}
return null;
}
}

java bean实体类结合上一篇生成的

public class Student {
private String id;
private String name;
public String getId() {
return id;
}
public void setId(String id) {
this.id = id;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}

}

这是freemarker模板文件mapperMysqlTemplate.ftl

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE mapper PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN" "http://mybatis.org/dtd/mybatis-3-mapper.dtd">
<mapper namespace="${objectName}Mapper">

<!-- 新增-->
<insert id="save" parameterType="${pack}">
insert into ${table}(
<#list fieldList as var>
${var},
</#list>
${id}
) values (
<#list fieldList as var>
${r"#{"}${var}${r"}"},
</#list>
${r"#{"}${id}${r"}"}
)
</insert>

<!-- 删除-->
<delete id="delete" parameterType="${pack}">
delete from ${table}
where
${id} = ${r"#{"}${id}${r"}"}
</delete>

<!-- 修改 -->
<update id="edit" parameterType="${pack}">
update  ${table}
set
<#list fieldList as var>
<#if var??>
${var} = ${r"#{"}${var}${r"}"},
</#if>
</#list>
where
${id} = ${r"#{"}${id}${r"}"}
</update>

<!-- 通过ID获取数据 -->
<select id="findById" parameterType="java.lang.String" resultType="${pack}">
select
<#list fieldList as var>
${var},
</#list>
${id}
from
${table}
where
${id} = ${r"#{"}${id}${r"}"}
</select>

<!-- 列表(全部) -->
<select id="listAll"  resultType="${pack}">
select
<#list fieldList as var>
a.${var},
</#list>
a.${id}
from
${table} a
</select>

</mapper>

查找数据库表字段的工具类

import java.io.BufferedWriter;
import java.io.File;
import java.io.FileWriter;
import java.io.IOException;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.ResultSetMetaData;
import java.sql.SQLException;
import java.util.ArrayList;
import java.util.List;

public class ReflectBean {
private Connection connection;
/*mysql url的连接字符串*/
private static String url = "jdbc:mysql://127.0.0.1:3306/wechat?useUnicode=true&characterEncoding=UTF-8";
//账号
private static String user = "root";
//密码
private static String password = "123456";

//mysql jdbc的java包驱动字符串
private String driverClassName = "com.mysql.jdbc.Driver";
//数据库中的表名
private String table;
public String getTable() {
return table;
}

public void setTable(String table) {
this.table = table;
}

//数据库的列名称
private String[] colnames; // 列名数组
//列名类型数组
private String[] colTypes;

public String[] getColnames() {
return colnames;
}

public void setColnames(String[] colnames) {
this.colnames = colnames;
}

public String[] getColTypes() {
return colTypes;
}

public void setColTypes(String[] colTypes) {
this.colTypes = colTypes;
}

public Connection getConnection() {
return connection;
}
public void setConnection(Connection connection) {
this.connection = connection;
}

public ReflectBean(){
try {//驱动注册
Class.forName(driverClassName);
if (connection == null || connection.isClosed())
//获得链接
connection = DriverManager.getConnection(url, user, password);
} catch (ClassNotFoundException ex) {
ex.printStackTrace();
System.out.println("Oh,not");
} catch (SQLException e) {
e.printStackTrace();
System.out.println("Oh,not");
}
}

public List<String> doAction(){
String sql = "select * from "+table;
List<String> list = new ArrayList<String>();
try {
PreparedStatement statement = connection.prepareStatement(sql);
//获取数据库的元数据
ResultSetMetaData metadata = statement.getMetaData();
ResultSet rs = connection.getMetaData().getPrimaryKeys(null, null, table);
String id = "";
//获取组键字段
if(rs.next()){
id = rs.getString(4);
}
//数据库的字段个数
int len = metadata.getColumnCount();
//字段名称
colnames = new String[len+1];
//字段类型 --->已经转化为java中的类名称了
colTypes = new String[len+1];
for(int i= 1;i<=len;i++){
//System.out.println(metadata.getColumnName(i)+":"+metadata.getColumnTypeName(i)+":"+sqlType2JavaType(metadata.getColumnTypeName(i).toLowerCase())+":"+metadata.getColumnDisplaySize(i));
//metadata.getColumnDisplaySize(i);
colnames[i] = metadata.getColumnName(i); //获取字段名称
list.add( colnames[i]);
colTypes[i] = sqlType2JavaType(metadata.getColumnTypeName(i)); //获取字段类型
}
list.add(id);
} catch (SQLException e) {
e.printStackTrace();
}
return list;
}

/*
* mysql的字段类型转化为java的类型*/
private String sqlType2JavaType(String sqlType) {

if(sqlType.equalsIgnoreCase("bit")){
return "boolean";
}else if(sqlType.equalsIgnoreCase("tinyint")){
return "byte";
}else if(sqlType.equalsIgnoreCase("smallint")){
return "short";
}else if(sqlType.equalsIgnoreCase("int")){
return "int";
}else if(sqlType.equalsIgnoreCase("bigint")){
return "long";
}else if(sqlType.equalsIgnoreCase("float")){
return "float";
}else if(sqlType.equalsIgnoreCase("decimal") || sqlType.equalsIgnoreCase("numeric")
|| sqlType.equalsIgnoreCase("real") || sqlType.equalsIgnoreCase("money")
|| sqlType.equalsIgnoreCase("smallmoney")){
return "double";
}else if(sqlType.equalsIgnoreCase("varchar") || sqlType.equalsIgnoreCase("char")
|| sqlType.equalsIgnoreCase("nvarchar") || sqlType.equalsIgnoreCase("nchar")
|| sqlType.equalsIgnoreCase("text")){
return "String";
}else if(sqlType.equalsIgnoreCase("datetime") ||sqlType.equalsIgnoreCase("date")){
return "Date";
}else if(sqlType.equalsIgnoreCase("image")){
return "Blod";
}else if(sqlType.equalsIgnoreCase("timestamp")){
return "Timestamp";
}

return null;
}
/*获取整个类的字符串并且输出为java文件
* */
public  StringBuffer getClassStr(){
//输出的类字符串
StringBuffer str = new StringBuffer("");
//获取表类型和表名的字段名
this.doAction();
//校验
if(null == colnames && null == colTypes) return null;
//拼接
str.append("public class "+GetTuoFeng(table)+" {\r\n");
//拼接属性
for(int index=1; index < colnames.length ; index++){
str.append(getAttrbuteString(colnames[index],colTypes[index]));
}
//拼接get，Set方法
for(int index=1; index < colnames.length ; index++){
str.append(getGetMethodString(colnames[index],colTypes[index]));
str.append(getSetMethodString(colnames[index],colTypes[index]));
}
str.append("}\r\n");
//输出到文件中
File file = new File("E:/mengwx/【源码】mysql版本_spring4.0/FHMYSQL/src/com/fh/entity/"+GetTuoFeng(table)+".java");
BufferedWriter write = null;

try {
write = new BufferedWriter(new FileWriter(file));
write.write(str.toString());
write.close();
} catch (IOException e) {

e.printStackTrace();
if (write != null)
try {
write.close();
} catch (IOException e1) {
e1.printStackTrace();
}
}
return str;
}
/*
* 获取字段字符串*/
public StringBuffer getAttrbuteString(String name, String type) {
if(!check(name,type)) {
System.out.println("类中有属性或者类型为空");
return null;
};
String format = String.format("    private %s %s;\n\r", new String[]{type,name});
return new StringBuffer(format);
}
/*
* 校验name和type是否合法*/
public boolean check(String name, String type) {
if("".equals(name) || name == null || name.trim().length() ==0){
return false;
}
if("".equals(type) || type == null || type.trim().length() ==0){
return false;
}
return true;

}
/*
* 获取get方法字符串*/
private StringBuffer getGetMethodString(String name, String type) {
if(!check(name,type)) {
System.out.println("类中有属性或者类型为空");
return null;
};
String Methodname = "get"+GetTuoFeng(name);
String format = String.format("    public %s %s(){\n\r", new Object[]{type,Methodname});
format += String.format("        return this.%s;\r\n", new Object[]{name});
format += "    }\r\n";
return new StringBuffer(format);
}
//将名称首字符大写
private String GetTuoFeng(String name) {
name = name.trim();
if(name.length() > 1){
name = name.substring(0, 1).toUpperCase()+name.substring(1);
}else
{
name = name.toUpperCase();
}
return name;
}
/*
* 获取字段的get方法字符串*/
private Object getSetMethodString(String name, String type) {
if(!check(name,type)) {
System.out.println("类中有属性或者类型为空");
return null;
};
String Methodname = "set"+GetTuoFeng(name);
String format = String.format("    public void %s(%s %s){\n\r", new Object[]{Methodname,type,name});
format += String.format("        this.%s = %s;\r\n", new Object[]{name,name});
format += "    }\r\n";
return new StringBuffer(format);
}

public static void main(String[] args) {
ReflectBean bean = new ReflectBean();
System.err.println(bean.getClassStr());
}

}

生成mapper.xml的工具类

import java.util.Date;
import java.util.HashMap;
import java.util.List;
import java.util.Map;

import com.mengwx.entiy.Student;
import com.mengwx.util.Freemarker;
import com.mengwx.util.ReflectBean;

public class CreateCodeController{

/**
* 生成代码
*/
public static void proCode(Object object,String table) throws Exception{
String objectName = object.getClass().getSimpleName();
String pack = object.getClass().getName();
ReflectBean re = new ReflectBean();
re.setTable(table);
List<String> list = re.doAction();
Map<String,Object> root = new HashMap<String,Object>();
String id = "";
if(list.size()>=1){//创建数据模型
id = list.get(list.size()-1);
}
root.put("packageName", objectName);
root.put("pack", pack);	//包名
root.put("objectName", objectName);							//类名
root.put("objectNameLower", objectName.toLowerCase());		//类名(全小写)
root.put("objectNameUpper", objectName.toUpperCase());		//类名(全大写)
root.put("nowDate", new Date());							//当前日期
root.put("table", table);
root.put("id", list.get(list.size()-1));
list.remove(list.size()-1);
list.remove(id);
root.put("fieldList", list);
String filePath = "C:/Users/huxf/workspace/createcode/src/com/mengwx/code/";	//存放路径
String ftlPath = "C:/Users/huxf/workspace/createcode/src/com/mengwx/ftl";		//ftl路径

/*生成mybatis xml*/
Freemarker.printFile("mapperMysqlTemplate.ftl", root, ""+Student.class.getSimpleName()+"Mapper.xml", filePath, ftlPath);

}

public static void main(String[] args) throws Exception {

proCode(new Student(),"student");
}

}

生成的mapper.xml文件

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE mapper PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN" "http://mybatis.org/dtd/mybatis-3-mapper.dtd">
<mapper namespace="StudentMapper">

<!-- 新增-->
<insert id="save" parameterType="com.mengwx.entiy.Student">
insert into student(
name,
id
) values (
#{name},
#{id}
)
</insert>

<!-- 删除-->
<delete id="delete" parameterType="com.mengwx.entiy.Student">
delete from student
where
id = #{id}
</delete>

<!-- 修改 -->
<update id="edit" parameterType="com.mengwx.entiy.Student">
update  student
set
name = #{name},
where
id = #{id}
</update>

<!-- 通过ID获取数据 -->
<select id="findById" parameterType="java.lang.String" resultType="com.mengwx.entiy.Student">
select
name,
id
from
student
where
id = #{id}
</select>

<!-- 列表(全部) -->
<select id="listAll"  resultType="com.mengwx.entiy.Student">
select
a.name,
a.id
from
student a
</select>

</mapper>

项目目录结构  StudentMapper.xml是生成的文件