MySQL表转Java对象【小工具】

表：

image.png

Model：

image.png
1.查询表中所有的列及注释

SET SESSION group_concat_max_len = 10240; -- 如果表中字段太长显示不全，执行该句。

select GROUP_CONCAT(COLUMN_TYPE,'@!@!',COLUMN_COMMENT,'@!@!',COLUMN_NAME separator '&!&!') from information_schema.COLUMNS
where table_name = 't_pc_chatroom_message' -- @!@!， &!&!自定义分隔符，防止注释部分破坏分割规则

查询结果：
bigint(64) unsigned@!@!主键ID@!@!id&!&!varchar(50)@!@!@!@!message_id&!&!varchar(50)@!@!租户id@!@!tenant_id&!&!varchar(50)@!@!群db_id@!@!wechat_chatroom_id&!&!varchar(50)@!@!微信db_id@!@!wechat_account_id ...
2.代码分割

public static void main(String[] args) {
       String str = "bigint(64) unsigned@!@!主键ID@!@!id&!&!varchar(50)@!@!@!@!message_id&!&!varchar(50)@!@!租户id@!@!tenant_id&!&!varchar(50)@!@!群db_id@!@!wechat_chatroom_id&!&!varchar(50)@!@!微信db_id@!@!wechat_account_id";
       String[] line = str.split("&!&!");
       StringBuilder sb = new StringBuilder();
       for (int i = 0; i < line.length; i++) {
           String subLine = line[i];

           String[] subLineArr = subLine.split("@!@!");
           sb.append("/**\n");
           sb.append("* " + subLineArr[subLineArr.length-2]+"\n");
           sb.append("*/\n");
           sb.append("private");
           sb.append(" ");
           if(subLineArr[0].contains("(")){
               sb.append(toSqlToJava(subLineArr[0].substring(0,subLineArr[0].indexOf("("))));
           }else{
               sb.append(toSqlToJava(subLineArr[0]));
           }

           sb.append(" ");
           String var = subLineArr[subLineArr.length-1];
           if(var.contains("_")){
               var = CaseFormat.LOWER_UNDERSCORE.to(CaseFormat.LOWER_CAMEL, var);
           }
           sb.append(var);
           sb.append(";");
           sb.append("\n");
       }
       System.out.println(sb);

   }
   //百度找的工具
   public static String toSqlToJava(String sqlType) {
       if( sqlType == null || sqlType.trim().length() == 0 ) return sqlType;
       sqlType = sqlType.toLowerCase();
       switch(sqlType){
           case "nvarchar":return "String";
           case "char":return "String";
           case "varchar":return "String";
           case "text":return "String";
           case "longtext":return "String";
           case "nchar":return "String";
           case "blob":return "byte[]";
           case "integer":return "Long";
           case "tinyint":return "Integer";
           case "smallint":return "Integer";
           case "mediumint":return "Integer";
           case "bit":return "Boolean";
           case "bigint":return "Long";
           case "float":return "Fload";
           case "double":return "Double";
           case "decimal":return "BigDecimal";
           case "boolean":return "Boolean";
           case "id":return "Long";
           case "date":return "LocalDate";
           case "datetime":return "LocalDateTime";
           case "year":return "Date";
           case "time":return "java.sql.Time";
           case "timestamp":return "Date";
           case "numeric":return "BigDecimal";
           case "real":return "BigDecimal";
           case "money":return "Double";
           case "smallmoney":return "Double";
           case "image":return "byte[]";
           case "mediumtext":return "String";
           case "json":return "String";
           case "int":return "Integer";
           default:
               System.out.println("-----------------》转化失败：未发现的类型"+sqlType);
               break;
       }
       return sqlType;
   }

3.带下划线字段转驼峰使用guava。

<dependency>
    <groupId>com.google.guava</groupId>
    <artifactId>guava</artifactId>
    <version>21.0</version>
</dependency>

Over.