示例涉及的技术点：使用ext做前后端数据传输、sql语句拼接技巧、hql分页查询、hql模板类的编写
示例描述：在网页上输入姓名、部门名称、职务的条件进行信息查询
首先定义页面上的查询按钮，访问查询接口
buttons : [{
text : '查询',
handler : function() {
var data = form.getForm().getValues();
Ext.apply(_this.currStore.baseParams, {
args : Ext.encode(data)
});
//传入条件参数并加载store进行查询
_this.currStore.load({
params : {
args : Ext.encode(data)
}
});
}
}, {
text : '重置',
handler : function() {
form.getForm().reset();
}
}],
items : [{
layout : 'column',
items : [{
columnWidth : .33,
layout : 'form',
items : [{
xtype : 'textfield',
fieldLabel : '姓名',
name : 'xm',
maxLength : 20,
anchor : '90%'
}]
}, {
columnWidth : .33,
layout : 'form',
items : [{
xtype : 'textfield',
fieldLabel : '部门名称',
name : 'deptName',
anchor : '90%'
}]
},{
columnWidth : .33,
layout : 'form',
items : [{
xtype : 'textfield',
fieldLabel : '职务',
name : 'zwmc',
anchor : '90%'
}]
}]
}]
然后定义store的结构：
var store = new Ext.data.JsonStore({
url : _this.queryUrl,
baseParams : {
args : "{}",
start : 0,
limit : config.PAGE_SIZE
},
totalProperty : 'result.total',
root : 'result.list',
fields : ['tid', 'xm', 'mobilePhone1', 'telephone',
'email', 'skype', 'sfzh', 'mobilePhone1', 'fax',
'qq', 'comment','deptName','deptId','email2','csrq',
'lxmc','xlmc','zwmc','lxid','xlid','zwid','sex','email2','dqqxpz','ysdwId','ysdwmc','is_ysdwry']
});
store.load();
this.currStore = store;
从中可以看出store的数据加载来自于queryUrl接口，这是一个用springmvc做的controller。这个接口在js文件中引入：
queryUrl : getRootPath() + "sys/ygxx/queryPagerByCxtj",
其响应的controller的实现：
@RequestMapping("/queryPagerByCxtj")
public ModelAndView queryPagerByCxtj(String args, int start, int limit) {
try {
YgxxSearchBean ygxxSearch = JSON.parseObject(args, YgxxSearchBean.class);
Pager pager = ygxxService.queryPageByCxtj(ygxxSearch, start, limit);
return handlerSuccess("分页查询员工成功", pager);
} catch (RuntimeException e) {
return handlerException("分页查询员工失败", e);
}
}
服务层的接口与实现为：
public Pager queryPageByCxtj(YgxxSearchBean ygxxSearch, int start, int limit);
public Pager queryPageByCxtj(YgxxSearchBean ygxxSearch, int start, int limit) {
return ygxxDao.queryPageByCxtj(ygxxSearch, start, limit);
}
其调用的dao层的接口与实现为：
public Pager queryPageByCxtj(YgxxSearchBean ygxxSearch,int start, int limit);
public Pager queryPageByCxtj(YgxxSearchBean ygxxSearch, int start, int limit) {
Map res = getHql(ygxxSearch);
String hql = (String) res.get("hql");
Map parameter = (Map) res
.get("parameter");
return getHqlQuery().findPager(hql.toString(), parameter, start, limit);
}
首先显然这里用了一个getHql()方法去拼接要求的hql语句。
以下是底层sql语句的拼接（值得分析）：
private Map getHql(YgxxSearchBean bean) {
StringBuffer hql = new StringBuffer(
"from Ygxx ygxx where ygxx.logicaldeletecode = 0 and ygxx.xm != 'sss' and ygxx.xm != 'sss' ");
Map res = new HashMap();
Map parameter = new HashMap();
if (bean != null) {
if (bean.getDeptId() != null) {
hql.append(" and ygxx.deptId = :deptId");
parameter.put("deptId", bean.getDeptId());
}
if (!Utils.isEmpty(bean.getDeptName())) {
hql.append(" and ygxx.deptName like :deptName");
parameter.put("deptName", "%" + bean.getDeptName() + "%");
}
if (!Utils.isEmpty(bean.getZwmc())) {
hql.append(" and ygxx.zwmc like :zwmc");
parameter.put("zwmc", "%" + bean.getZwmc() + "%");
}
if (!Utils.isEmpty(bean.getXm())) {
hql.append(" and ygxx.xm like :xm");
parameter.put("xm", "%" + bean.getXm() + "%");
}
if(Utils.isNotEmpty(bean.getMobilePhone1())) {
hql.append(" and ygxx.mobilePhone1 like :mobilePhone1");
parameter.put("mobilePhone1", "%" + bean.getMobilePhone1() + "%");
}
if(Utils.isNotEmpty(bean.getMobilePhone2())) {
hql.append(" and ygxx.mobilePhone2 like :mobilePhone2");
parameter.put("mobilePhone2", "%" + bean.getMobilePhone2() + "%");
}
if(Utils.isNotEmpty(bean.getTelephone())) {
hql.append(" and ygxx.telephone like :telephone");
parameter.put("telephone", "%" + bean.getTelephone() + "%");
}
if(Utils.isNotEmpty(bean.getEmail())) {
hql.append(" and ygxx.email like :email");
parameter.put("email", "%" + bean.getEmail() + "%");
}
if(Utils.isNotEmpty(bean.getFax())) {
hql.append(" and ygxx.fax like :fax");
parameter.put("fax", "%" + bean.getFax() + "%");
}
if(Utils.isNotEmpty(bean.getYgids())) {
hql.append(" and ygxx.tid in (").append(bean.getYgids()).append(")");
}
}
hql.append(" order by tid desc ");
res.put("hql", hql.toString());
res.put("parameter", parameter);
return res;
}
其次这里的return语句中的getHqlQuery().findPager()方法也值得深思。
以下是该findPager()方法的实现：
public Pager findPager(String queryString, Map parameters, int start, int limit) {
Assert.INSTANCE.assertNotEmpty("queryString is empty", queryString);
Assert.INSTANCE.assertNotNull("parameters is null", parameters);
Assert.INSTANCE.assertTrue("start < 0", start >= 0);
Assert.INSTANCE.assertTrue("limit <= 0", limit > 0);
HibernateCallback callback = createQueryForPagerHibernateCallback(queryString, parameters, start,
limit);
return getHibernateTemplate().execute(callback);
}
这里的return语句依旧调用了hibernate模板方法：
public T execute(HibernateCallback action) throws DataAccessException {
return this.doExecute(action, false, false);
}
自己调了doExecute()方法：
protected T doExecute(HibernateCallback action, boolean enforceNewSession, boolean enforceNativeSession) throws DataAccessException {
Assert.notNull(action, "Callback object must not be null");
Session session = enforceNewSession ? SessionFactoryUtils.getNewSession(this.getSessionFactory(), this.getEntityInterceptor()) : this.getSession();
boolean existingTransaction = !enforceNewSession && (!this.isAllowCreate() || SessionFactoryUtils.isSessionTransactional(session, this.getSessionFactory()));
if (existingTransaction) {
this.logger.debug("Found thread-bound Session for HibernateTemplate");
}
FlushMode previousFlushMode = null;
Object var9;
try {
previousFlushMode = this.applyFlushMode(session, existingTransaction);
this.enableFilters(session);
Session sessionToExpose = !enforceNativeSession && !this.isExposeNativeSession() ? this.createSessionProxy(session) : session;
T result = action.doInHibernate(sessionToExpose);
this.flushIfNecessary(session, existingTransaction);
var9 = result;
} catch (HibernateException var15) {
throw this.convertHibernateAccessException(var15);
} catch (SQLException var16) {
throw this.convertJdbcAccessException(var16);
} catch (RuntimeException var17) {
throw var17;
} finally {
if (existingTransaction) {
this.logger.debug("Not closing pre-bound Hibernate Session after HibernateTemplate");
this.disableFilters(session);
if (previousFlushMode != null) {
session.setFlushMode(previousFlushMode);
}
} else if (this.isAlwaysUseNewSession()) {
SessionFactoryUtils.closeSession(session);
} else {
SessionFactoryUtils.closeSessionOrRegisterDeferredClose(session, this.getSessionFactory());
}
}
return var9;
}
到此已到底部。