zoukankan      html  css  js  c++  java
  • JDBC通用DAO

    dbcBaseDao接口,内容如下:

    package com.sun4j.core.jdbc.dao;
    
    import java.io.Serializable;
    import java.util.List;
    import java.util.Map;
    
    import org.springframework.jdbc.core.JdbcTemplate;
    import org.springframework.jdbc.support.rowset.SqlRowSet;
    
    public interface JdbcBaseDao<T> {
    
        void save(T entity);
    
        void update(T entity);
    
        void delete(T entity);
    
        void delete(Serializable id);
    
        void deleteAll();
    
        T findById(Serializable id);
    
        List<T> findAll();
    
        void batchDelete(Serializable[] ids);
    
        void batchUpdate(List<T> list);
    
        void batchSave(List<T> list);
    
        Map<String, Object> findOne(String sql, Object... args);
    
        List<Map<String, Object>> findListMap(String sql, Object... args);
    
        void execSQL(String sql);
    
        SqlRowSet rowSet(String sql, Object... args);
    
        JdbcTemplate getJdbcTemplate();
    
    }
    

    JdbcBaseDaoImpl 实现

    package com.sun4j.core.jdbc.dao.impl;
    
    import java.io.Serializable;
    import java.lang.reflect.Field;
    import java.lang.reflect.ParameterizedType;
    import java.sql.Types;
    import java.util.ArrayList;
    import java.util.List;
    import java.util.Map;
    
    import org.springframework.beans.factory.annotation.Autowired;
    import org.springframework.jdbc.core.BeanPropertyRowMapper;
    import org.springframework.jdbc.core.JdbcTemplate;
    import org.springframework.jdbc.core.RowMapper;
    import org.springframework.jdbc.support.rowset.SqlRowSet;
    import org.springframework.util.Assert;
    
    import com.sun4j.core.jdbc.dao.JdbcBaseDao;
    
    public class JdbcBaseDaoImpl<T> implements JdbcBaseDao<T> {
        public static final String SQL_INSERT = "insert";
        public static final String SQL_UPDATE = "update";
        public static final String SQL_DELETE = "delete";
        @Autowired
        private JdbcTemplate jdbcTemplate;
    
        private Class<T> entityClass;
    
        @SuppressWarnings("unchecked")
        public JdbcBaseDaoImpl() {
            ParameterizedType type = (ParameterizedType) getClass().getGenericSuperclass();
            entityClass = (Class<T>) type.getActualTypeArguments()[0];
            System.out.println("Dao实现类是:" + entityClass.getName());
        }
    
        @Override
        public void save(T entity) {
            String sql = this.makeSql(SQL_INSERT);
            Object[] args = this.setArgs(entity, SQL_INSERT);
            int[] argTypes = this.setArgTypes(entity, SQL_INSERT);
            jdbcTemplate.update(sql.toString(), args, argTypes);
        }
    
        @Override
        public void update(T entity) {
            String sql = this.makeSql(SQL_UPDATE);
            Object[] args = this.setArgs(entity, SQL_UPDATE);
            int[] argTypes = this.setArgTypes(entity, SQL_UPDATE);
            jdbcTemplate.update(sql, args, argTypes);
        }
    
        @Override
        public void delete(T entity) {
            String sql = this.makeSql(SQL_DELETE);
            Object[] args = this.setArgs(entity, SQL_DELETE);
            int[] argTypes = this.setArgTypes(entity, SQL_DELETE);
            jdbcTemplate.update(sql, args, argTypes);
        }
    
        @Override
        public void deleteAll() {
            String sql = " TRUNCATE TABLE " + entityClass.getSimpleName();
            jdbcTemplate.execute(sql);
        }
    
        @Override
        public void delete(Serializable id) {
            String sql = " DELETE FROM " + entityClass.getSimpleName() + " WHERE id=?";
            jdbcTemplate.update(sql, id);
        }
    
        @Override
        public void batchSave(List<T> lt) {
            Assert.notEmpty(lt);
            StringBuilder sb = new StringBuilder();
            sb.append("insert into ").append(entityClass.getSimpleName().toLowerCase()).append("( ");
            List<Object[]> params = new ArrayList<Object[]>();
            String val = "";
    
            for (T t : lt) {
                int index = 0;
                Field[] fields = t.getClass().getDeclaredFields();
                if (fields != null && fields.length > 0) {
                    Object[] objVal = new Object[fields.length];
    
                    for (Field field : fields) {
                        try {
                            field.setAccessible(true);
                            Object obj = field.get(t);
                            if (params.size() == 0) {
                                sb.append(field.getName()).append(" ,");
                                val += ", ? ";
                            }
                            objVal[index++] = obj;
                        } catch (Exception e) {
                            e.printStackTrace();
                        }
                    }
                    params.add(objVal);
                }
            }
            sb.deleteCharAt(sb.length() - 1);
            val = val.substring(1);
            sb.append(") value (").append(val).append(")");
            String sql = sb.toString();
            jdbcTemplate.batchUpdate(sql, params);
        }
    
        @Override
        public void batchUpdate(List<T> lt) {
            Assert.notEmpty(lt);
            StringBuilder sb = new StringBuilder();
            sb.append("update ").append(entityClass.getSimpleName().toLowerCase()).append(" set ");
            List<Object[]> params = new ArrayList<Object[]>();
            Object primaryKey = "id";
            for (T t : lt) {
                int index = 0;
                Field[] fields = entityClass.getDeclaredFields();
                if (fields != null && fields.length > 0) {
                    Object id = null;
                    Object[] objVal = new Object[fields.length];
                    for (Field field : fields) {
                        try {
                            field.setAccessible(true);
                            Object obj = field.get(t);
                            if (field.getName().equalsIgnoreCase("id")) {
                                primaryKey = obj;
                                id = obj;
                            } else {
                                if (params.size() == 0) {
                                    sb.append(field.getName()).append(" = ? ,");
                                }
                                objVal[index++] = obj;
                            }
                        } catch (Exception e) {
                            e.printStackTrace();
                        }
                        objVal[index] = id;
                    }
                    params.add(objVal);
                }
            }
            sb.deleteCharAt(sb.length() - 1);
            sb.append(" where ").append(primaryKey).append(" = ? ");
            String sql = sb.toString();
            jdbcTemplate.batchUpdate(sql, params);
        }
    
        @Override
        public T findById(Serializable id) {
            String sql = "SELECT * FROM " + entityClass.getSimpleName() + " WHERE id=?";
            RowMapper<T> rowMapper = BeanPropertyRowMapper.newInstance(entityClass);
            return jdbcTemplate.query(sql, rowMapper, id).get(0);
        }
    
        @Override
        public List<T> findAll() {
            String sql = "SELECT * FROM " + entityClass.getSimpleName();
            RowMapper<T> rowMapper = BeanPropertyRowMapper.newInstance(entityClass);
            return jdbcTemplate.query(sql, rowMapper);
        }
    
        @Override
        public Map<String, Object> findOne(String sql, Object... args) {
            return jdbcTemplate.queryForMap(sql, args);
        }
    
        @Override
        public List<Map<String, Object>> findListMap(String sql, Object... args) {
            return jdbcTemplate.queryForList(sql, args);
        }
    
        @Override
        public void execSQL(String sql) {
            jdbcTemplate.execute(sql);
        }
    
        @Override
        public SqlRowSet rowSet(String sql, Object... args) {
            return this.jdbcTemplate.queryForRowSet(sql, args);
        }
    
        @Override
        public JdbcTemplate getJdbcTemplate() {
            return jdbcTemplate;
        }
    
        /**
         * 组装SQl
         * 
         * @param entityClass
         * @param sqlFlag
         * @return
         */
        public String makeSql(String sqlFlag) {
            StringBuffer sql = new StringBuffer();
            Field[] fields = entityClass.getDeclaredFields();
            if (sqlFlag.equals(SQL_INSERT)) {
                sql.append(" INSERT INTO " + entityClass.getSimpleName());
                sql.append("(");
                for (int i = 0; fields != null && i < fields.length; i++) {
                    fields[i].setAccessible(true); // 暴力反射
                    String column = fields[i].getName();
                    sql.append(column).append(",");
                }
                sql = sql.deleteCharAt(sql.length() - 1);
                sql.append(") VALUES (");
                for (int i = 0; fields != null && i < fields.length; i++) {
                    sql.append("?,");
                }
                sql = sql.deleteCharAt(sql.length() - 1);
                sql.append(")");
            } else if (sqlFlag.equals(SQL_UPDATE)) {
                sql.append(" UPDATE " + entityClass.getSimpleName() + " SET ");
                for (int i = 0; fields != null && i < fields.length; i++) {
                    fields[i].setAccessible(true); // 暴力反射
                    String column = fields[i].getName();
                    if (column.equals("id")) { // id 代表主键
                        continue;
                    }
                    sql.append(column).append("=").append("?,");
                }
                sql = sql.deleteCharAt(sql.length() - 1);
                sql.append(" WHERE id=?");
            } else if (sqlFlag.equals(SQL_DELETE)) {
                sql.append(" DELETE FROM " + entityClass.getSimpleName() + " WHERE id=?");
            }
            System.out.println("SQL=" + sql);
            return sql.toString();
        }
    
        /**
         * 设置参数
         * 
         * @param entity
         * @param sqlFlag
         * @param entityClass
         * @return
         */
        public Object[] setArgs(T entity, String sqlFlag) {
            Field[] fields = entityClass.getDeclaredFields();
            if (sqlFlag.equals(SQL_INSERT)) {
                Object[] args = new Object[fields.length];
                for (int i = 0; args != null && i < args.length; i++) {
                    try {
                        fields[i].setAccessible(true); // 暴力反射
                        args[i] = fields[i].get(entity);
                    } catch (Exception e) {
                        e.printStackTrace();
                    }
                }
                return args;
            } else if (sqlFlag.equals(SQL_UPDATE)) {
                Object[] tempArr = new Object[fields.length];
                for (int i = 0; tempArr != null && i < tempArr.length; i++) {
                    try {
                        fields[i].setAccessible(true); // 暴力反射
                        tempArr[i] = fields[i].get(entity);
                    } catch (Exception e) {
                        e.printStackTrace();
                    }
                }
                Object[] args = new Object[fields.length];
                System.arraycopy(tempArr, 1, args, 0, tempArr.length - 1); // 数组拷贝
                args[args.length - 1] = tempArr[0];
                return args;
            } else if (sqlFlag.equals(SQL_DELETE)) {
                Object[] args = new Object[1]; // 长度是1
                fields[0].setAccessible(true); // 暴力反射
                try {
                    args[0] = fields[0].get(entity);
                } catch (Exception e) {
                    e.printStackTrace();
                }
                return args;
            }
            return null;
        }
    
        /**
         * 设置参数类型(写的不全,只是一些常用的)
         * 
         * @param entity
         * @param sqlFlag
         * @param entityClass
         * @return
         */
        public int[] setArgTypes(T entity, String sqlFlag) {
            Field[] fields = entityClass.getDeclaredFields();
            if (sqlFlag.equals(SQL_INSERT)) {
                int[] argTypes = new int[fields.length];
                try {
                    for (int i = 0; argTypes != null && i < argTypes.length; i++) {
                        fields[i].setAccessible(true); // 暴力反射
                        if (fields[i].get(entity).getClass().getName().equals("java.lang.String")) {
                            argTypes[i] = Types.VARCHAR;
                        } else if (fields[i].get(entity).getClass().getName().equals("java.lang.Double")) {
                            argTypes[i] = Types.DECIMAL;
                        } else if (fields[i].get(entity).getClass().getName().equals("java.lang.Integer")) {
                            argTypes[i] = Types.INTEGER;
                        } else if (fields[i].get(entity).getClass().getName().equals("java.util.Date")) {
                            argTypes[i] = Types.DATE;
                        }
                    }
                } catch (Exception e) {
                    e.printStackTrace();
                }
                return argTypes;
            } else if (sqlFlag.equals(SQL_UPDATE)) {
                int[] tempArgTypes = new int[fields.length];
                int[] argTypes = new int[fields.length];
                try {
                    for (int i = 0; tempArgTypes != null && i < tempArgTypes.length; i++) {
                        fields[i].setAccessible(true); // 暴力反射
                        if (fields[i].get(entity).getClass().getName().equals("java.lang.String")) {
                            tempArgTypes[i] = Types.VARCHAR;
                        } else if (fields[i].get(entity).getClass().getName().equals("java.lang.Double")) {
                            tempArgTypes[i] = Types.DECIMAL;
                        } else if (fields[i].get(entity).getClass().getName().equals("java.lang.Integer")) {
                            tempArgTypes[i] = Types.INTEGER;
                        } else if (fields[i].get(entity).getClass().getName().equals("java.util.Date")) {
                            tempArgTypes[i] = Types.DATE;
                        }
                    }
                    System.arraycopy(tempArgTypes, 1, argTypes, 0, tempArgTypes.length - 1); // 数组拷贝
                    argTypes[argTypes.length - 1] = tempArgTypes[0];
    
                } catch (Exception e) {
                    e.printStackTrace();
                }
                return argTypes;
    
            } else if (sqlFlag.equals(SQL_DELETE)) {
                int[] argTypes = new int[1]; // 长度是1
                try {
                    fields[0].setAccessible(true); // 暴力反射
                    if (fields[0].get(entity).getClass().getName().equals("java.lang.String")) {
                        argTypes[0] = Types.VARCHAR;
                    } else if (fields[0].get(entity).getClass().getName().equals("java.lang.Integer")) {
                        argTypes[0] = Types.INTEGER;
                    }
    
                } catch (Exception e) {
                    e.printStackTrace();
                }
                return argTypes;
            }
            return null;
        }
    
        @Override
        public void batchDelete(Serializable[] ids) {
            String idStr="";
            for (int i = 0; i < ids.length; i++) {
                idStr+=",'"+ids[i]+"'";
            }
            String sql = " DELETE FROM " + entityClass.getSimpleName() + " WHERE id in (?)";
            jdbcTemplate.update(sql, idStr.charAt(1));
        }
    
    }
    

    通用的JdbcBaseService

    package com.sun4j.core.jdbc.service;
    
    import java.io.Serializable;
    import java.util.List;
    import java.util.Map;
    
    public interface JdbcBaseService<T> {
    
        void save(T entity);
    
        void update(T entity);
    
        void delete(T entity);
    
        void delete(Serializable id);
    
        void deleteAll();
    
        T findById(Serializable id);
    
        List<T> findAll();
    
        void batchDelete(Serializable[] ids);
    
        void batchUpdate(List<T> list);
    
        void batchSave(List<T> list);
    
        Map<String, Object> findOne(Object... args);
    
        List<Map<String, Object>> findListMap(Object... args);
    }
    

    通用的JdbcBaseService实现

    package com.sun4j.core.jdbc.service.impl;
    
    import java.io.Serializable;
    import java.util.List;
    import java.util.Map;
    
    import com.sun4j.core.jdbc.dao.JdbcBaseDao;
    import com.sun4j.core.jdbc.service.JdbcBaseService;
    
    public abstract class JdbcBaseServiceImpl<T> implements JdbcBaseService<T> {
        protected abstract JdbcBaseDao<T> jdbcDao();
    
        @Override
        public void save(T entity) {
            jdbcDao().save(entity);
        }
    
        @Override
        public void update(T entity) {
            jdbcDao().update(entity);
        }
    
        @Override
        public void delete(T entity) {
            jdbcDao().delete(entity);
        }
    
        @Override
        public void delete(Serializable id) {
            jdbcDao().delete(id);
        }
    
        @Override
        public void deleteAll() {
            jdbcDao().deleteAll();
        }
    
        @Override
        public T findById(Serializable id) {
            return jdbcDao().findById(id);
        }
    
        @Override
        public List<T> findAll() {
            return jdbcDao().findAll();
        }
    
        @Override
        public void batchDelete(Serializable[] ids) {
            jdbcDao().batchDelete(ids);
        }
    
        @Override
        public void batchUpdate(List<T> list) {
            jdbcDao().batchUpdate(list);
        }
    
        @Override
        public void batchSave(List<T> list) {
            jdbcDao().batchSave(list);
        }
    
        @Override
        public abstract Map<String, Object> findOne(Object... args);
    
        @Override
        public abstract List<Map<String, Object>> findListMap(Object... args);
    } 

      

      

      

  • 相关阅读:
    解决Chrome 70及以上版本的证书问题:Failed to load resource: net::ERR_CERT_SYMANTEC_LEGACY
    VUE使用axios数据请求时报错 TypeError: Cannot set property 'xxxx' of undefined 的解决办法
    生辰八字推算
    OneNote巧妙设置标题
    Kibana安装与介绍
    Logstash入门简介
    Metricbeat入门简介
    FileBeats入门简介
    ElasticSearch集群部署
    ElasticSearch安装与介绍
  • 原文地址:https://www.cnblogs.com/JAYIT/p/7685403.html
Copyright © 2011-2022 走看看