JFinal框架操作oracle数据库
JFinal框架操作oracle数据库,需要在configPlugin()方法中配置链接oracle数据库的相关配置 配置JFinal数据库操作插件,configPlugin方法 这里我加载jdbc.properties配置文件实在configConstant加载的 @Overridepublic void configConstant(Constants me) {lo
JFinal框架操作oracle数据库,需要在configPlugin()方法中配置链接oracle数据库的相关配置
配置JFinal数据库操作插件,configPlugin方法
这里我加载jdbc.properties配置文件实在configConstant加载的
@Override public void configConstant(Constants me) { loadPropertyFile("jdbc.properties");//加载配置文件 me.setDevMode(getPropertyToBoolean("config.devModel", false)); me.setViewType(ViewType.JSP); me.setEncoding("UTF-8"); }
jdbc.properites配置文件
oracle.driver=oracle.jdbc.driver.OracleDriver oracle.url=jdbc:oracle:thin:@127.0.0.1:1521:orcl oracle.username=scott oracle.password=xiaohu config.devModel=true
@Override public void configPlugin(Plugins me) { ActiveRecordPlugin arp=null; String driver=getProperty("oracle.driver"); String url=getProperty("oracle.url"); String username=getProperty("oracle.username"); String password=getProperty("oracle.password"); DruidPlugin dp=new DruidPlugin(url, username, password, driver); me.add(dp); arp=new ActiveRecordPlugin(dp);//设置数据库方言 arp.setDialect(new OracleDialect()); arp.setContainerFactory(new CaseInsensitiveContainerFactory());//忽略大小写 me.add(new EhCachePlugin()); arp.addMapping("users", "id",Users.class); me.add(arp); }
需要注意一点的是,由于oracle数据库中在创建表时,会自动的将所有的字段自动转为大写,因此在避免后面操作的时候出现大小写错误的相关异常,这里需要配置忽略大小写的功能
arp.setContainerFactory(new CaseInsensitiveContainerFactory());//忽略大小写
如果不需要对数据库进行增加操作,则必须配置忽略大小写,如果不配置忽略大小写,在保存源代码的该段代码中会出现属性id找不到的异常
/** * Save model. */ public boolean save() { Config config = getConfig(); Table table = getTable(); StringBuilder sql = new StringBuilder(); List<object> paras = new ArrayList<object>(); config.dialect.forModelSave(table, attrs, sql, paras); // if (paras.size() == 0) return false; // The sql "insert into tableName() values()" works fine, so delete this line // -------- Connection conn = null; PreparedStatement pst = null; int result = 0; try { conn = config.getConnection(); if (config.dialect.isOracle()) pst = conn.prepareStatement(sql.toString(), new String[]{table.getPrimaryKey()}); else pst = conn.prepareStatement(sql.toString(), Statement.RETURN_GENERATED_KEYS); config.dialect.fillStatement(pst, paras); result = pst.executeUpdate(); <span style="color:#ff0000;">getGeneratedKey(pst, table);//如果不配置忽略大小写,执行到这里会出现异常,虽然可以添加到数据库,但是这里报错,界面还是会显示500错误</span></object></object>
getModifyFlag().clear(); return result >= 1; } catch (Exception e) { throw new ActiveRecordException(e); } finally { config.close(pst, conn); } }
<span style="color:#ff0000;">getGeneratedKey()源代码部分</span>
/** * Get id after save method. */ private void getGeneratedKey(PreparedStatement pst, Table table) throws SQLException { String pKey = table.getPrimaryKey(); if (get(pKey) == null || getConfig().dialect.isOracle()) { ResultSet rs = pst.getGeneratedKeys(); if (rs.next()) { Class colType = table.getColumnType(pKey); if (colType == Integer.class || colType == int.class) set(pKey, rs.getInt(1)); else if (colType == Long.class || colType == long.class) set(pKey, rs.getLong(1)); else set(pKey, rs.getObject(1)); // It returns Long object for int colType rs.close(); } } }
set()源代码部分
/** * Set attribute to model. * @param attr the attribute name of the model * @param value the value of the attribute * @return this model * @throws ActiveRecordException if the attribute is not exists of the model */ public M set(String attr, Object value) { <span style="color:#ff0000;">if (getTable().hasColumnLabel(attr)) {//执行到这里返回false</span> attrs.put(attr, value); getModifyFlag().add(attr); // Add modify flag, update() need this flag. return (M)this; } throw new ActiveRecordException("The attribute name is not exists: " + attr);//抛出该异常 }
现在来说说如果不配置,为什么会出现 The attribute name is not exists:这个异常,这是因为oracle中的字段是大写的,而set方法中传入的attr属性的值是小写,而getTable()中的属性对应的就是oracle字段,这些属性则是大写,因此这里使用getTable().hasColumnLabel(attr)判断是否存在该字段,就会找不到,这时就会抛出该异常,因此就必须配置忽略大小写的方法,就不会出现该异常
实体类:
package com.tenghu.core.model; import com.jfinal.plugin.activerecord.Model; public class Users extends Model<users>{ public static Users dao=new Users(); }</users>
操作数据:
Users users=new Users(); users.set("id", "users_sequence.nextval"); users.set("username", "张三"); users.set("pwd", "sdfsdfs"); users.save(); List<users> testList=Users.dao.find("select * from users");</users>

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