1 项目简介
需要提前在数据库建好表，然后执行代码生成工具，会生成简单的Java文件，避免重复编写增删改查代码。类似的工具网上有很多，本人开发这个工具属于自娱自乐。这个专栏会记录开发的过程。
2 项目搭建
数据库使用MySQL ：8.1.0
JDK使用1.8
1、新建一个普通的Java项目。GeneraJava项目是实际开发工具。GeneraJavaDemo是生成之后的模块。目录结构如下：
2、新建GeneraJava模块（普通的maven项目）。pom.xml内容如下：
<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
<modelVersion>4.0.0</modelVersion>
<groupId>com.sourceJava</groupId>
<artifactId>GeneraJava</artifactId>
<version>1.0-SNAPSHOT</version>
<properties>
<maven.compiler.source>8</maven.compiler.source>
<maven.compiler.target>8</maven.compiler.target>
<project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
<mysql.version>8.0.17</mysql.version>
<apache.commons.version>3.4</apache.commons.version>
<lombok.version>1.16.18</lombok.version>
</properties>
<dependencies>
<dependency>
<groupId>mysql</groupId>
<artifactId>mysql-connector-java</artifactId>
<version>${mysql.version}</version>
</dependency>
<dependency>
<groupId>org.projectlombok</groupId>
<artifactId>lombok</artifactId>
<version>${lombok.version}</version>
</dependency>
<dependency>
<groupId>org.apache.commons</groupId>
<artifactId>commons-lang3</artifactId>
<version>${apache.commons.version}</version>
</dependency>
<dependency>
<groupId>com.fasterxml.jackson.core</groupId>
<artifactId>jackson-annotations</artifactId>
<version>2.11.2</version>
</dependency>
</dependencies>
</project>
3、application.properties 内容如下：
db.driver.name=com.mysql.cj.jdbc.Driver db.url=jdbc:mysql://localhost:3306/generatejava?autoReconnect=true&useUnicode=true&characterEncoding=utf8&zeroDateTimeBehavior=CONVERT_TO_NULL&useSSL=false&serverTimezone=CTT&allowMultiQueries=true db.username=数据库账号 db.password=数据库密码 #忽略表前缀 ignore.table.prefix=true #参数bean后缀 suffix.bean.param=query #文件输出路径 path.base=xxx/MyGeneraJava/GeneraJavaDemo/src/main/ #包名 package.base=com.generajava package.pojo=entity.pojo package.param=entity.query #需要忽略的属性 ignore.bean.tojson.field=companyId,status ignore.bean.tojson.expression=@JsonIgnore ignore.bean.tojson.class=import com.fasterxml.jackson.annotation.JsonIgnore; #日期格式序列化 bean.date.format.expresson=@JsonFormat(pattern="%s",timezone = "GMT+8") bean.date.format.class=import com.fasterxml.jackson.annotation.JsonFormat; #日期格式反序列化 bean.date.unformat.expresson=@DateTimeFormat(pattern = "%s") bean.date.unformat.class=import org.springframework.format.annotation.DateTimeFormat;
3 开发（基础模块）
3.1 PropertiesUtils.java 读取配置文件application.properties
package com.sourceJava.utils;
import java.io.InputStream;
import java.util.HashMap;
import java.util.Iterator;
import java.util.Map;
import java.util.Properties;
public class PropertiesUtils {
private static Properties properties = new Properties();
private static Map<String,String> PROPER_MAP = new HashMap<>();
static {
InputStream is = null;
try {
is = PropertiesUtils.class.getClassLoader().getResourceAsStream("application.properties");
properties.load(is);
Iterator<Object> it = properties.keySet().iterator();
while(it.hasNext()){
String key = (String) it.next();
PROPER_MAP.put(key,properties.getProperty(key));
}
}catch (Exception e){
e.printStackTrace();
}finally {
if(is != null){
try {
is.close();
}catch (Exception e1){
e1.printStackTrace();
}
}
}
}
public static String getValue(String key){
return PROPER_MAP.get(key);
}
public static void main(String[] args) {
System.out.println(getValue("db.driver.name"));
}
}
3.2 Constants.java 项目启动加载默认配置
package com.sourceJava.bean;
import com.sourceJava.utils.PropertiesUtils;
public class Constants {
public static Boolean IGNORE_TABLE_PERFIX;
public static String SUFFIX_BEAN_PARAM;
public final static String[] SQL_DATE_TIME_TYPE = new String[]{"datetime","timestamp"};
public final static String[] SQL_DATE_TYPE = new String[]{"date"};
public final static String[] SQL_DECIMAL_TYPE = new String[]{"decimal","double","float"};
public final static String[] SQL_STRING_TYPE = new String[]{"char","varchar","text","mediumtext","longtext"};
public final static String[] SQL_INTEGER_TYPE = new String[]{"int","tinyint"};
public final static String[] SQL_LONG_TYPE = new String[]{"bigint"};
private static String PATH_JAVA = "java";
private static String PATH_RESOURCE = "resource";
public static String PATH_BASE;
public static String PACKAGE_BASE;
public static String PATH_POJO;
public static String PACKAGE_POJO;
//需要忽略的属性
public static String IGNORE_BEAN_TOJSON_FIELD;
public static String IGNORE_BEAN_TOJSON_EXPRESSION;
public static String IGNORE_BEAN_TOJSON_CLASS;
//日期序列化
public static String BEAN_DATE_FORMAT_EXPRESSON;
public static String BEAN_DATE_FORMAT_CLASS;
//日期反序列化
public static String BEAN_DATE_UNFORMAT_EXPRESSON;
public static String BEAN_DATE_UNFORMAT_CLASS;
static {
IGNORE_BEAN_TOJSON_FIELD = PropertiesUtils.getValue("ignore.bean.tojson.field");
IGNORE_BEAN_TOJSON_EXPRESSION = PropertiesUtils.getValue("ignore.bean.tojson.expression");
IGNORE_BEAN_TOJSON_CLASS = PropertiesUtils.getValue("ignore.bean.tojson.class");
//日期序列化
BEAN_DATE_FORMAT_EXPRESSON = PropertiesUtils.getValue("bean.date.format.expresson");
BEAN_DATE_FORMAT_CLASS = PropertiesUtils.getValue("bean.date.format.class");
//日期反序列化
BEAN_DATE_UNFORMAT_EXPRESSON = PropertiesUtils.getValue("bean.date.unformat.expresson");
BEAN_DATE_UNFORMAT_CLASS = PropertiesUtils.getValue("bean.date.unformat.class");
IGNORE_TABLE_PERFIX = Boolean.valueOf(PropertiesUtils.getValue("ignore.table.prefix"));
SUFFIX_BEAN_PARAM = PropertiesUtils.getValue("suffix.bean.param");
PACKAGE_BASE = PropertiesUtils.getValue("package.base");
PACKAGE_POJO = PACKAGE_BASE + "." + PropertiesUtils.getValue("package.pojo");
PATH_BASE = PropertiesUtils.getValue("path.base");
PATH_BASE = PATH_BASE + PATH_JAVA;
PATH_BASE = PATH_BASE.replace(".","/");
PATH_POJO = PATH_BASE + "/" + PACKAGE_POJO.replace(".","/");
}
public static void main(String[] args) {
System.out.println(PACKAGE_POJO);
System.out.println(PATH_POJO);
}
}
3.3 tb_product_info.sql 数据脚本
SET NAMES utf8mb4;
SET FOREIGN_KEY_CHECKS = 0;
-- ----------------------------
-- Table structure for tb_product_info
-- ----------------------------
DROP TABLE IF EXISTS `tb_product_info`;
CREATE TABLE `tb_product_info` (
`id` int NOT NULL AUTO_INCREMENT COMMENT '主键',
`company_id` varchar(30) CHARACTER SET utf8mb4 COLLATE utf8mb4_0900_ai_ci NULL DEFAULT NULL COMMENT '公司ID',
`code` varchar(11) CHARACTER SET utf8mb4 COLLATE utf8mb4_0900_ai_ci NULL DEFAULT NULL COMMENT '公司编码',
`product_name` varchar(200) CHARACTER SET utf8mb4 COLLATE utf8mb4_0900_ai_ci NULL DEFAULT NULL COMMENT '商品名称',
`price` decimal(15, 2) NULL DEFAULT NULL COMMENT '商品价格',
`sku_type` tinyint NULL DEFAULT NULL COMMENT 'sku类型',
`color_type` tinyint NULL DEFAULT NULL COMMENT '颜色类型',
`craete_time` datetime NULL DEFAULT NULL COMMENT '创建时间',
`crate_date` date NULL DEFAULT NULL COMMENT '创建日期',
`stock` bigint NULL DEFAULT NULL COMMENT '库存',
`status` tinyint NULL DEFAULT NULL COMMENT '状态',
PRIMARY KEY (`id`) USING BTREE,
UNIQUE INDEX `idx_code`(`code`) USING BTREE,
INDEX `idx_sku_type`(`sku_type`) USING BTREE
) ENGINE = InnoDB CHARACTER SET = utf8mb4 COLLATE = utf8mb4_0900_ai_ci COMMENT = '商品信息表' ROW_FORMAT = Dynamic;
SET FOREIGN_KEY_CHECKS = 1;3.4 TableInfo.java 定义表通用属性
public class TableInfo {
private String tableName;//表名
private String beanName;//bean名称
private String beanParamName;//参数名称
private String comment;//注释
private Map<String, List<FieldInfo>> keyIndexMap = new LinkedHashMap<>();//唯一索引集合
private Boolean haveDate = false;//是否有date类型
private Boolean haveDateTime = false;//是否有时间类型
private Boolean haveBigDecimal = false;//是否有bigdecimal类型
private List<FieldInfo> fieldInfoList = new ArrayList();
public List<FieldInfo> getFieldInfoList() {
return fieldInfoList;
}
public void setFieldInfoList(List<FieldInfo> fieldInfoList) {
this.fieldInfoList = fieldInfoList;
}
public String getTableName() {
return tableName;
}
public void setTableName(String tableName) {
this.tableName = tableName;
}
public String getBeanName() {
return beanName;
}
public void setBeanName(String beanName) {
this.beanName = beanName;
}
public String getBeanParamName() {
return beanParamName;
}
public void setBeanParamName(String beanParamName) {
this.beanParamName = beanParamName;
}
public String getComment() {
return comment;
}
public void setComment(String comment) {
this.comment = comment;
}
public Map<String, List<FieldInfo>> getKeyIndexMap() {
return keyIndexMap;
}
public void setKeyIndexMap(Map<String, List<FieldInfo>> keyIndexMap) {
this.keyIndexMap = keyIndexMap;
}
public Boolean getHaveDate() {
return haveDate;
}
public void setHaveDate(Boolean haveDate) {
this.haveDate = haveDate;
}
public Boolean getHaveDateTime() {
return haveDateTime;
}
public void setHaveDateTime(Boolean haveDateTime) {
this.haveDateTime = haveDateTime;
}
public Boolean getHaveBigDecimal() {
return haveBigDecimal;
}
public void setHaveBigDecimal(Boolean haveBigDecimal) {
this.haveBigDecimal = haveBigDecimal;
}
@Override
public String toString() {
return "TableInfo{" +
"tableName='" + tableName + '\'' +
", beanName='" + beanName + '\'' +
", beanParamName='" + beanParamName + '\'' +
", comment='" + comment + '\'' +
", keyIndexMap=" + keyIndexMap +
", haveDate=" + haveDate +
", haveDateTime=" + haveDateTime +
", haveBigDecimal=" + haveBigDecimal +
", fieldInfoList=" + fieldInfoList +
'}';
}
}3.5 FieldInfo.java定义字段通用属性
public class FieldInfo {
private String fieldName;//字段名称
private String propertyName;//属性名称
private String sqlType;// 数据库字段类型
private String javaType;// Java字段类型
private String comment; //数据库字段备注
private Boolean isAutoIncrement;//是否自增
public String getFieldName() {
return fieldName;
}
public void setFieldName(String fieldName) {
this.fieldName = fieldName;
}
public String getPropertyName() {
return propertyName;
}
public void setPropertyName(String propertyName) {
this.propertyName = propertyName;
}
public String getSqlType() {
return sqlType;
}
public void setSqlType(String sqlType) {
this.sqlType = sqlType;
}
public String getJavaType() {
return javaType;
}
public void setJavaType(String javaType) {
this.javaType = javaType;
}
public String getComment() {
return comment;
}
public void setComment(String comment) {
this.comment = comment;
}
public Boolean getAutoIncrement() {
return isAutoIncrement;
}
public void setAutoIncrement(Boolean autoIncrement) {
isAutoIncrement = autoIncrement;
}
@Override
public String toString() {
return "FieldInfo{" +
"fieldName='" + fieldName + '\'' +
", propertyName='" + propertyName + '\'' +
", sqlType='" + sqlType + '\'' +
", javaType='" + javaType + '\'' +
", comment='" + comment + '\'' +
", isAutoIncrement=" + isAutoIncrement +
'}';
}
}3.6 MyStringUtils.java字符串工具类
public class MyStringUtils {
//第一个字母转换为大写
public static String upCaseFirstLetter(String field){
if(org.apache.commons.lang3.StringUtils.isEmpty(field)){
return field;
}
return field.substring(0,1).toUpperCase() + field.substring(1);
}
//第一个字母转换成小写
public static String lowerCaseFirstLetter(String field){
if(org.apache.commons.lang3.StringUtils.isEmpty(field)){
return field;
}
return field.substring(0,1).toLowerCase() + field.substring(1);
}
}3.7 DateUtils.java 日期工具类
public class DateUtils {
public static final String YYYY_MM_DD = "yyyy-MM-dd";
public static final String _YYYY_MM_DD = "yyyy/MM/dd";
public static final String YYYY_MM_DD_HH_MM_SS = "yyyy-MM-dd HH:mm:ss";
//Date 转 String
public static String dateParseToString(String pattern, Date date){
return new SimpleDateFormat(pattern).format(date);
}
//String 转 Date
public static Date stringParseToDate(String date,String pattern) throws ParseException {
return new SimpleDateFormat(pattern).parse(date);
}
}
