使用freemarker模板生成简单的代码

Dear 丶 2022-12-06 04:27 237阅读 0赞

#### main方法 ####

public class FreemarkerUtils {
        public static void main(String[] args) throws Exception {
            createFtl("user_role_relation");
        }
    
        public static void createFtl(String... str) throws Exception {
            for (String string : str) {
                String tableName = string.toUpperCase();
                /** 生成文件目录 */
                String path = "d:\\bean/";
                File f = new File(path);
                if (!f.exists()) {
                    f.mkdir();
                }
                Map<String, Object> map = DBHelper.getTableInfo(tableName);
                String clsName = map.get("clsName").toString();
                // 执行插值，并输出到指定的输出流中
                createFile("sqlxml.ftl", path + clsName + "Mapper.xml", map);
                createFile("bean.ftl", path + clsName + ".java", map);
                createFile("dao.ftl", path + clsName + "Dao.java", map);
                System.out.println("创建完成");
            }
        }
    
     
        public static void createFile(String templatName, String fileName, Map<String, Object> map) throws IOException, TemplateException {
            @SuppressWarnings("deprecation")
            Configuration cfg = new Configuration();
            String path = FreemarkerUtils.class.getResource("/").getPath() + "ftlProject";
            cfg.setDirectoryForTemplateLoading(new File(path));
            Template t = cfg.getTemplate(templatName);
            t.process(map, new OutputStreamWriter(new FileOutputStream(fileName)));
        }
    
    }

### DB工具类 ###

public class DBHelper {
    
        /** 参数 */
        private static final String URL       = "jdbc:oracle:thin:@127.0.0.1:orcl";
        /** 参数 */
        private static final String CLSDRIVER = "oracle.jdbc.OracleDriver";
    
        /** 数据库用户名 */
        private static final String USERNME   = "xx";
        /** 数据库密码 */
        private static final String PWD       = "xx";
    
    
        private static Connection getConnection() {
            Connection connection = null;
            try {
                Class.forName(CLSDRIVER);
                connection = DriverManager.getConnection(URL, USERNME, PWD);
            } catch (ClassNotFoundException e) {
                e.printStackTrace();
            } catch (SQLException e) {
                e.printStackTrace();
            }
            return connection;
        }
    
    
        private static ResultSet select(String sql) {
            Connection conn = getConnection();
            ResultSet rs = null;
            try {
                Statement cs = conn.createStatement();
                rs = cs.executeQuery(sql);
            } catch (SQLException e) {
                e.printStackTrace();
            }
            return rs;
        }
    
      
        public static Map<String, Object> getTableInfo(String tableName) {
            Map<String, Object> item = new LinkedHashMap<String, Object>();
    
            StringBuffer sbsql = new StringBuffer("SELECT T.TABLE_NAME ,");
            sbsql.append("T.COLUMN_NAME ,T.DATA_TYPE ,TC.COMMENTS , T.DATA_LENGTH, T.NULLABLE,T.DATA_DEFAULT");
            sbsql.append(" FROM user_tab_columns T ,");
            sbsql.append(" user_col_comments TC WHERE T.COLUMN_NAME = TC.COLUMN_NAME AND T.TABLE_NAME = TC.TABLE_NAME AND");
            sbsql.append(" T.TABLE_NAME = '").append(tableName);
            sbsql.append("' AND T.COLUMN_NAME != 'OGG_SEQ_ID' order by column_id ");
            // sbsql.append("' AND T.COLUMN_NAME != 'OGG_SEQ_ID' ORDER BY NULLABLE DESC");
    
            System.out.println(sbsql.toString());
            ResultSet rs = select(sbsql.toString());
            try {
    
                List<Map<String, Object>> clist = new ArrayList<Map<String, Object>>();
                int i = 1;
                while (rs.next()) {
                    Map<String, Object> citem = new LinkedHashMap<String, Object>();
                    /** 字段名 */
                    String columnName = rs.getString("COLUMN_NAME");
                    /** 字段描述 */
                    String columnDesc = rs.getString("COMMENTS");
                    String columnClsName = changeClumn(columnName);
                    String columnType = changeDateType(rs.getString("DATA_TYPE"));
                    String columnClsType = changeClsType(columnType);
                    String isNull = rs.getString("NULLABLE");
                    /** 字段名、Java类字段、字段描述、字段类型、Java类字段类型 */
                    citem.put("columnName", columnName);
                    citem.put("columnClsName", columnClsName);
                    citem.put("columnDesc", columnDesc);
                    citem.put("columnType", columnType);
                    citem.put("columnClsType", columnClsType);
                    citem.put("isNull", isNull);
                    citem.put("curSize", i++);
                    clist.add(citem);
                }
                item.put("TABLINFO", clist);
                item.put("MAXSIZE", clist.size());
            } catch (Exception e) {
                e.printStackTrace();
            }
            item.put("tableName", tableName);
            item.put("clsName", changeClsName(tableName));
            item.put("curTime", getCurrTime());
            item.put("curDate", getCurrDate());
            return item;
        }
        public static String getCurrDate() {
            DateFormat df = new SimpleDateFormat("yyyyMMdd");
            return df.format(new Date());
        }
    
        public static String getCurrTime() {
            DateFormat df = new SimpleDateFormat("HHmmss");
            return df.format(new Date());
        }
    
        private static String changeClsName(String tableName) {
            StringBuffer sb = new StringBuffer();
            String lowerCase = tableName.toLowerCase();
            boolean f = false;
            int i = 1;
            for (char c : lowerCase.toCharArray()) {
                int a = (int) c;
                if (a == 95) {
                    f = true;
                    i++;
                    continue;
                }
                if (f || i == 1) {
                    sb.append((c + "").toUpperCase());
                    f = false;
                } else {
                    sb.append(c);
                }
                i++;
            }
            return sb.toString();
        }
      
        private static String changeClumn(String str) {
            StringBuffer sb = new StringBuffer();
            String lowerCase = str.toLowerCase();
            boolean f = false;
            for (char c : lowerCase.toCharArray()) {
                int a = (int) c;
                if (a == 95) {
                    f = true;
                    continue;
                }
                if (f) {
                    sb.append((c + "").toUpperCase());
                    f = false;
                } else {
                    sb.append(c);
                }
            }
            return sb.toString();
        }
    
      
        private static String changeDateType(String dataType) {
    
            if ("VARCHAR2".equalsIgnoreCase(dataType)) {
                return JdbcType.VARCHAR.name().toString();
            } else if ("CHAR".equalsIgnoreCase(dataType)) {
                return JdbcType.CHAR.name().toString();
            } else if ("NVARCHAR2".equalsIgnoreCase(dataType)) {
                return JdbcType.NVARCHAR.name().toString();
            } else if ("CLOB".equalsIgnoreCase(dataType)) {
                return JdbcType.CLOB.name().toString();
            } else if ("BLOB".equalsIgnoreCase(dataType)) {
                return JdbcType.BLOB.name().toString();
            } else if ("DATE".equalsIgnoreCase(dataType)) {
                return JdbcType.DATE.name().toString();
            } else if ("RAW".equalsIgnoreCase(dataType)) {
                return JdbcType.BLOB.name().toString();
            } else if ("LONG".equalsIgnoreCase(dataType)) {
                return JdbcType.BIGINT.name().toString();
            } else if ("NUMBER".equalsIgnoreCase(dataType)) {
                return JdbcType.NUMERIC.name().toString();
            } else if ("UROWID".equalsIgnoreCase(dataType)) {
                return JdbcType.BLOB.name().toString();
            } else {
                return "VARCHAR";
            }
        }
    
       
        private static String changeClsType(String dataType) {
    
            if (dataType.equalsIgnoreCase(JdbcType.VARCHAR.name().toString())) {
                return String.class.getSimpleName();
            } else if (dataType.equalsIgnoreCase(JdbcType.CHAR.name().toString())) {
                return String.class.getSimpleName();
            } else if (dataType.equalsIgnoreCase(JdbcType.CLOB.name().toString())) {
                return String.class.getSimpleName();
            } else if (dataType.equalsIgnoreCase(JdbcType.BLOB.name().toString())) {
                return String.class.getSimpleName();
            } else if (dataType.equalsIgnoreCase(JdbcType.DATE.name().toString())) {
                return "java.util.Date";
            } else if (dataType.equalsIgnoreCase(JdbcType.BLOB.name().toString())) {
                return String.class.getSimpleName();
            } else if (dataType.equalsIgnoreCase(JdbcType.BIGINT.name().toString())) {
                return Long.class.getSimpleName();
            } else if (dataType.equalsIgnoreCase(JdbcType.NUMERIC.name().toString())) {
                return BigDecimal.class.getSimpleName();
            } else {
                return String.class.getSimpleName();
            }
        }
    
    
    
    }

### bean.ftl 实体对象的模板 ###

public class ${clsName} extends BaseEntity {
    
    	/** 序号 */
        private static final long serialVersionUID = 1L;
    
    	<#list TABLINFO as x>
       	/** 属性描述：${x.columnDesc} */	
        private ${x.columnClsType}            ${x.columnClsName};
       	</#list>
       	
      	<#list TABLINFO as x>
     
        public ${x.columnClsType} get${x.columnClsName?cap_first}() {
            return ${x.columnClsName};
        }
     
    
        public void set${x.columnClsName?cap_first}(${x.columnClsType} ${x.columnClsName}) {
            this.${x.columnClsName} = ${x.columnClsName};
        }
       
        </#list>
       	
    
    }

### dao层的模板 ###

package com.imobpay.base.dao;
    import com.imobpay.base.iface.BaseDao;
    public interface ${clsName}Dao<T>  {
            public void insert(T bean);
            public void update(T bean);
            public void delete(T bean);
            public T selectById(T bean);
             public List<T> list(T bean);
             public Integer listCount(T bean);
    }

### sqlxml.ftl SQL层的模板 ###

<#macro mapperEl value>${r"#{"}${value}}</#macro>
    <?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="com.imobpay.base.dao.${clsName}Dao">
    
        <#--  生成查询参数  -->
    
        <sql id="paramSql">
            
            <#list TABLINFO as x >
                <if test="${x.columnClsName} !=null and ${x.columnClsName} !=''">
                    AND ${x.columnName} = <@mapperEl  x.columnClsName  />
                </if>
            </#list>
        </sql>
    
    
        <#--  查询单个对像  -->
        <select id="selectById" parameterType="com.imobpay.base.entity.${clsName}" resultType="com.imobpay.base.entity.${clsName}">
            SELECT * FROM ${tableName} WHERE ROWNUM = 1
            <include refid="paramSql"></include>
        </select>
    
        <#--  分页查询  -->
        <select id="list" parameterType="com.imobpay.base.entity.${clsName}" resultType="com.imobpay.base.entity.${clsName}">
            <if test="pageflag==true">
                SELECT * FROM (
                SELECT A.*, ROWNUM RN FROM
                (
                SELECT * FROM ${tableName} WHERE 1=1
                <include refid="paramSql"></include>
                ) A WHERE ROWNUM <= <@mapperEl  'curPage'  />*<@mapperEl  'pageSize'  />
                ) WHERE RN >
                (<@mapperEl  'curPage'  />-1)*<@mapperEl  'pageSize'  />
            </if>
            <if test="pageBlag==false">
                SELECT * FROM ${tableName}
                WHERE 1=1
                <include refid="paramSql"></include>
            </if>
        </select>
    
        <#--  分页个数查询  -->
        <select id="listCount" parameterType="com.imobpay.base.entity.${clsName}" resultType="Integer">
            SELECT count(1) as count FROM ${tableName}
            WHERE 1=1
            <include refid="paramSql"></include>
        </select>
    
        
        <insert id="insert" parameterType="com.imobpay.base.entity.${clsName}">
            INSERT INTO
            ${tableName}(
            <#list TABLINFO as x >
            <#if x.curSize == MAXSIZE>
                ${x.columnName}
            <#else>${x.columnName},</#if>
            </#list>)
            VALUES(<#list TABLINFO as x ><#if x.curSize == MAXSIZE>
            <@mapperEl  x.columnClsName /><#else>
            <@mapperEl  x.columnClsName  />,
        </#if></#list>)
        </insert>
    
        
    
        <update id="update">
            UPDATE ${tableName}
            <trim prefix="SET" suffixOverrides=",">
                <#list TABLINFO as x >
                    <if test="${x.columnClsName} !=null and ${x.columnClsName} !=''">
                        ${x.columnName} = <@mapperEl  x.columnClsName  /> ,
                    </if>
                </#list>
            </trim>
            WHERE 1=1
            <include refid="paramSql"></include>
        </update>
    
    </mapper>

### 目录结构 ###

![在这里插入图片描述][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3UwMTAzMTYxODg_size_16_color_FFFFFF_t_70_pic_center]

运行这个FreemarkerUtils里面的main方法就可以了。

依赖的jar包就是这个几个  
![在这里插入图片描述][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3UwMTAzMTYxODg_size_16_color_FFFFFF_t_70_pic_center 1]

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