Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 $=n|MbFl
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 &C3J6uCm+
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据这一功能,我设计了通用的抽象Bean基类和分页类支持,代码来 :{C#<g`
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自于Quake Wang的javaeye-core包的相应类,然后又做了很多修改 !z X`M1J
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分页支持类: -MoI{3a
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java代码: $lci{D32,
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package com.javaeye.common.util; v')Fq[H
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import java.util.List; Yd lXMddE
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publicclass PaginationSupport { D M{7x77
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publicfinalstaticint PAGESIZE = 30; Q4-d2I>0
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privateint pageSize = PAGESIZE; g^"",!J/
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privateList items; YEAiL C+q
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privateint totalCount; yInW?3
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privateint[] indexes = newint[0]; e{.2*>pH
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privateint startIndex = 0; /s
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public PaginationSupport(List items, int J`;G9'n2
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totalCount){ 5 |{0|mP
setPageSize(PAGESIZE); VR2BdfKU,
setTotalCount(totalCount); +w:[By"
setItems(items); pNr3u
setStartIndex(0); YMad]_XOP
} ZU7e1VaZM
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public PaginationSupport(List items, int C78YHjy
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totalCount, int startIndex){ .
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setPageSize(PAGESIZE); gCz^JM
setTotalCount(totalCount); d"uR1rTk
setItems(items); IfeG"ua|
setStartIndex(startIndex); ,sP7/S)FR
} 'wvZnb
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public PaginationSupport(List items, int Erl"X}P
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totalCount, int pageSize, int startIndex){ 'g^;_=^G
setPageSize(pageSize); kM*f9x
setTotalCount(totalCount); ;"
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setItems(items); lLxKC7b
setStartIndex(startIndex); }7+G'=XI/
} 0XSZ3dY&+
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publicList getItems(){ QL"fC;xUn,
return items; &!2
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} O1Ey{2Q
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publicvoid setItems(List items){ Tf
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this.items = items; *5hg}[n2
} }I}Rq D:`
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publicint getPageSize(){ ,;y5Mu8
return pageSize; ^,
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} ~A}"s-Kq5
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publicvoid setPageSize(int pageSize){ 0SwWLq
this.pageSize = pageSize; 1,T8@8#
} ]L^X}[SH
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publicint getTotalCount(){ )/HSt%>
return totalCount; I{JU<A,&
} D0v!fF~
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publicvoid setTotalCount(int totalCount){ ;iy]mPd
if(totalCount > 0){ `LVItP(GUM
this.totalCount = totalCount; ea3AcT6
int count = totalCount / aU<0<Dx
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pageSize; ':R)i.TS
if(totalCount % pageSize > 0) p
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count++; ~=aGv%vX
indexes = newint[count]; V?kJYf(<
for(int i = 0; i < count; i++){ )3=oS1p
indexes = pageSize * <@.f#
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} )Uw
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}else{ &q#$SU,$(
this.totalCount = 0; P+:FiVj@~
} wz +
} &Y\Vh}
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publicint[] getIndexes(){ ib /B!?/
return indexes; w1KLQd:yq
} eG72=l)Mz
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publicvoid setIndexes(int[] indexes){ 4Smno%jq
this.indexes = indexes; KRd.Ubs -
} i*:lZ eU61
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publicint getStartIndex(){ >k<.bEx(A
return startIndex; @`G_6<.`
} d!{,[8&
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publicvoid setStartIndex(int startIndex){ :O-Y67>&
if(totalCount <= 0) n,hHh=.Fu
this.startIndex = 0; T;w%-k\<r
elseif(startIndex >= totalCount) @aN<nd`q)
this.startIndex = indexes ,)hUL/r6
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[indexes.length - 1]; DPw"UY:
elseif(startIndex < 0) TFb9gOTJ
this.startIndex = 0; Ytm t+9
else{ 9n]zh-
this.startIndex = indexes '*MNRduE6
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[startIndex / pageSize]; MLtfi{;LH
} m]R< :_
} /zMiy?
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publicint getNextIndex(){ a)^f`s^aa
int nextIndex = getStartIndex() + wo5"f}vd#
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pageSize; ;Xk-hhR
if(nextIndex >= totalCount) <]eWr:;
return getStartIndex(); 'e_^s+l)a
else r0379 _
return nextIndex; r&@#,g
} NVU @m+m~
}
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publicint getPreviousIndex(){ e7T"?s
int previousIndex = getStartIndex() - `*mctjSN
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pageSize; v!27q*;8H
if(previousIndex < 0) >p [|U`>{
return0; i
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else PVH^yWi
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return previousIndex; Y*/:IYr`
} 7(rNJPrU~=
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} HhDiGzOSi
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抽象业务类 ];i-d7C
java代码: @GDe{GG+
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/** &b8Dy=#
* Created on 2005-7-12 nAPSs]D
*/ 4+e9:r]
package com.javaeye.common.business; uCO-f<b
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import java.io.Serializable; rCU f,)
import java.util.List; `T7gfb%1-3
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import org.hibernate.Criteria; s kC*
import org.hibernate.HibernateException; (7^5jo[D
import org.hibernate.Session; /\34o{
import org.hibernate.criterion.DetachedCriteria; ]Q1?Ox:'
import org.hibernate.criterion.Projections; L;N)l2m.\
import d/5i4g[q
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org.springframework.orm.hibernate3.HibernateCallback; .RFijr
import *"Yz"PK
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org.springframework.orm.hibernate3.support.HibernateDaoS JAJo^}}{b
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upport; *`$Y!uzG:\
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import com.javaeye.common.util.PaginationSupport; ,l/~epx4v)
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public abstract class AbstractManager extends Z Ear~
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HibernateDaoSupport { QJiU"1
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privateboolean cacheQueries = false; S. my" j
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privateString queryCacheRegion; +e
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publicvoid setCacheQueries(boolean WqQAt{W/<
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cacheQueries){ eaLR-+vEB
this.cacheQueries = cacheQueries; 6r
} 3ht>eaHi
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publicvoid setQueryCacheRegion(String N
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queryCacheRegion){ NqyKR&;
this.queryCacheRegion = 7|$cM7_r
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queryCacheRegion; +9mE1$C
} cHqT1EY
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publicvoid save(finalObject entity){ Cg{V"B:
getHibernateTemplate().save(entity); bu[PQsT
} y[QQopy4:
:
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publicvoid persist(finalObject entity){ ;rwjqUDBz
getHibernateTemplate().save(entity); 0_nY70B
} n1
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publicvoid update(finalObject entity){ ~V#MI@]V~
getHibernateTemplate().update(entity); z}Y23W&sX
} 9Q\CJ9
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publicvoid delete(finalObject entity){ NMaZ+g!t(
getHibernateTemplate().delete(entity); )9F o
} $H\[yg>4
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publicObject load(finalClass entity, K|n%8hRy
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finalSerializable id){ RLy2d'DS
return getHibernateTemplate().load ++>HU{
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(entity, id); d,%e?8x5
} eXs^YPi
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publicObject get(finalClass entity, >z{*>i,m1
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finalSerializable id){ rE->z
return getHibernateTemplate().get =2Vs))>Y
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(entity, id); h?Y->!'
} gu1:%raXd
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publicList findAll(finalClass entity){ qS8p )pw
return getHibernateTemplate().find("from c<k=8P
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" + entity.getName()); ON,sN
} &*Sgyk
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publicList findByNamedQuery(finalString u"$=:GK
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namedQuery){ OM>,1;UH]
return getHibernateTemplate H[WsHq;T+9
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().findByNamedQuery(namedQuery); UO1WtQyu,H
} O c,E\~
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publicList findByNamedQuery(finalString query, a-\M)}T
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finalObject parameter){ h0cdRi
return getHibernateTemplate 2uCw[iZM
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().findByNamedQuery(query, parameter); 3-=f@uH!
} $yn7XonS
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publicList findByNamedQuery(finalString query, e7_.Xr~[
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finalObject[] parameters){ -$ VP#%
return getHibernateTemplate MQ#nP_i
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().findByNamedQuery(query, parameters); h&|S*
} LJ8 t@ui
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publicList find(finalString query){ =,Zkg(M
return getHibernateTemplate().find sk%Xf,
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(query); GXnrVI
} FUO 9jX
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publicList find(finalString query, finalObject C>:,\=y%
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parameter){ zk;'`@7
return getHibernateTemplate().find n1Wo<$#
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(query, parameter); eY V Jk7
} KXiStwS
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public PaginationSupport findPageByCriteria %Q080Ltet
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(final DetachedCriteria detachedCriteria){ @kPe/j/[1
return findPageByCriteria 9*2Q'z}_
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); xE5VXYU
} so>jz@!EE
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public PaginationSupport findPageByCriteria 0t?g!
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(final DetachedCriteria detachedCriteria, finalint GboZ T68
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startIndex){ -y'tz,En.
return findPageByCriteria 4[
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(detachedCriteria, PaginationSupport.PAGESIZE, M#.dF{%%
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startIndex); m2\[L/W]
} %w;wQ_
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public PaginationSupport findPageByCriteria o&)v{q
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(final DetachedCriteria detachedCriteria, finalint "uP~hFA7M
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pageSize, ?BRZ){)
finalint startIndex){ Ov;q]Vn>
return(PaginationSupport) i.0d>G><@
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getHibernateTemplate().execute(new HibernateCallback(){ p:ubj'(U05
publicObject doInHibernate gbu*6&j9
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(Session session)throws HibernateException { +fN2%aC
Criteria criteria = b( ~#CHg
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detachedCriteria.getExecutableCriteria(session); 6Z5$cR_vC7
int totalCount = qGi\*sc>x
(@NW2
((Integer) criteria.setProjection(Projections.rowCount
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()).uniqueResult()).intValue(); g:YUuZ
criteria.setProjection E %?>
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(null); +4F; m_G6
List items = 8:U0M'}u>
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criteria.setFirstResult(startIndex).setMaxResults $S^rKp#
*G[` T%g
(pageSize).list(); D7Y?$=0ycb
PaginationSupport ps = p\}!uS4 (
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new PaginationSupport(items, totalCount, pageSize, 0x#
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startIndex); PHMp,z8
return ps; jGYl*EBx
} p2gu@!
}, true); [$M l;K
} hVdGxT]6
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public List findAllByCriteria(final Z
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DetachedCriteria detachedCriteria){ ]UrlFiR
return(List) getHibernateTemplate $#_^uWN-M
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().execute(new HibernateCallback(){ qv`:o
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publicObject doInHibernate z'zC
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(Session session)throws HibernateException { 7'5/T]Z
Criteria criteria = !v*#E{r"g=
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detachedCriteria.getExecutableCriteria(session); sA
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return criteria.list(); iHWt;]
} Lve$H(GHT
}, true); oTA'=<W?D
} <JZa
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public int getCountByCriteria(final s%?<:9
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DetachedCriteria detachedCriteria){ t5QGXj
Integer count = (Integer) JV!}"[
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getHibernateTemplate().execute(new HibernateCallback(){ TSsx^h8/
publicObject doInHibernate l4OPzNc'
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(Session session)throws HibernateException { b{W ,wn
Criteria criteria = P2)g%$ME
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detachedCriteria.getExecutableCriteria(session); 1'5!")r
return /PkOF((
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criteria.setProjection(Projections.rowCount +>v{#A_u
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()).uniqueResult(); ^N~Jm&I
} 6:\z8fYD
}, true); ;"%luQA<w
return count.intValue(); #p=Wt&2
} ,0$b8lb;x/
} g:"Hg-s
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用户在web层构造查询条件detachedCriteria,和可选的 FD}>}fLv
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 WTh|7&
to 3i!b
PaginationSupport的实例ps。 R7By=Y!t
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ps.getItems()得到已分页好的结果集 NPR{g!tK%
ps.getIndexes()得到分页索引的数组 P^*gk P
ps.getTotalCount()得到总结果数 \'N|1!EO|t
ps.getStartIndex()当前分页索引 d>7bwG+k
ps.getNextIndex()下一页索引 YJwz*@l
ps.getPreviousIndex()上一页索引 %n#^#:
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 Ljxn}):[
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,尤其是上面的示例代码,让我着实觉得该对我原来的分页查询做 X]*W +
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一下代码重构了。 u]cnbm
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我把原本我的做法也提供出来供大家讨论吧: K+mtuB]yr
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首先,为了实现分页查询,我封装了一个Page类: QX~*aqS3s8
java代码: i]LK,'
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/*Created on 2005-4-14*/ F]?$Q'U
package org.flyware.util.page; o6KBJx
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/** (^Do#3
* @author Joa ddHIP`wb
* :7>Si%
*/ 2i(|? XJ^
publicclass Page { Pjb9FCA'
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/** imply if the page has previous page */ IL:"]`f*
privateboolean hasPrePage; 5\Y/s o=
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/** imply if the page has next page */ #-HN[U?Gs
privateboolean hasNextPage; c[y=K)<Z
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/** the number of every page */ v,i:vT\~
privateint everyPage; Z#MODf0H@
1v\-jM"
/** the total page number */ /?XfVhA:A
privateint totalPage; dju&Ku
A^p $~e\)
/** the number of current page */ QT&{M
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privateint currentPage; }C&c=3V
l*:p==
/** the begin index of the records by the current t+(CAP|,
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query */ (
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privateint beginIndex; : }IS=A
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/** The default constructor */ ^c7L!F
public Page(){ z0W+4meoH
0?h .X=G
} 1a!h&!$9
r#}Sy\
/** construct the page by everyPage Fszk?0T
* @param everyPage /&dt!.WY^
* */ LGMFv
public Page(int everyPage){ N_DgnZ7*
this.everyPage = everyPage; 5y'Yosy:
} :ZIcWIV-
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/** The whole constructor */ r/T DU[`&
public Page(boolean hasPrePage, boolean hasNextPage, ]/']{*T1
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N.`]D)57
int everyPage, int totalPage, ,'673PR
int currentPage, int beginIndex){ yW&iUh=0
this.hasPrePage = hasPrePage; /YbL{G
)j}
this.hasNextPage = hasNextPage; ZD{srEa/a
this.everyPage = everyPage; ^Bb_NcU
this.totalPage = totalPage; >D;hT*3
this.currentPage = currentPage; ;hvXFU
this.beginIndex = beginIndex; $S}x'F!4_
} @ih}x
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/** zef,*dQY
* @return Mt Z(\&~
* Returns the beginIndex. ]>L]?Rm
*/ Em;b,x*U
publicint getBeginIndex(){ a=FRJQ8S
return beginIndex; }BrE|'.j'
} kI'A`
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/** [VW;L l
* @param beginIndex hI8C XG
* The beginIndex to set. j#f&!&G5<&
*/ FudD
publicvoid setBeginIndex(int beginIndex){ RX1{?*r]Z
this.beginIndex = beginIndex; 5uer
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} C(|5,P#5
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!
/** i 8Xz
* @return c1J)yv1y
* Returns the currentPage. NR&9:?
*/ ha=z<Q
publicint getCurrentPage(){ |q2lTbJ
return currentPage; H|U/tU-
} ]P$DAi
? myXG92
/** @t8kN6.
* @param currentPage fNPj8\#V,
* The currentPage to set. YXVJJd$U
*/ it@} dZ
publicvoid setCurrentPage(int currentPage){ ;
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this.currentPage = currentPage; ';,Bn9rv
} \]A;EwC4C
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/** ~!F4JRf
* @return 7$W;4!BN*
* Returns the everyPage. bV*zMoD#
*/ &AcFa<U
publicint getEveryPage(){ Gc!8v}[7J
return everyPage; V55J[s*6!
} m`IQ+,e
t} i97 ;
/** BemkCj2
* @param everyPage iv+jv2ZF%
* The everyPage to set. G5#}Ed4
*/ UX`DZb+^
publicvoid setEveryPage(int everyPage){ qmeml_(W
this.everyPage = everyPage; |p -R9A*>h
} 6//FZ:q
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/** ^Lmc%y
* @return TUUE(sLA
* Returns the hasNextPage. !LIfeL.4h
*/ _*ouo<x
publicboolean getHasNextPage(){ +^ DRto=
return hasNextPage; uy _i{Y|
} !x$:8R
u] U)d$|
/** qD;v/,?
* @param hasNextPage pl x/}ah8
* The hasNextPage to set. )s<WG}
*/ XyM(@6,'
publicvoid setHasNextPage(boolean hasNextPage){ 20l_ay
this.hasNextPage = hasNextPage; Z1$];Q\cX
} bV$8
>[`
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/** 9c^skNbS
* @return Wda\a.bXT
* Returns the hasPrePage. :#w+?LA*
*/ HIX=MprL<
publicboolean getHasPrePage(){ AX!>l;
return hasPrePage; mvTyx7h=
} z/0yO@_D/q
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q"/=[a
/** JC&6q>$
* @param hasPrePage J7ktfyQ0W
* The hasPrePage to set. 974eY
*/ o'^;tLs15
publicvoid setHasPrePage(boolean hasPrePage){ 'EL ||
this.hasPrePage = hasPrePage; w.D4dv_H
} u*26>.
AGEZ8(h
/** QP$nDK<
* @return Returns the totalPage. pymx\Hd,
* b~/Wnp5
*/ E#<7\p>
publicint getTotalPage(){ bk7^%O>
return totalPage; NqT1buU#
} t}]9VD9
#juGD9e
/** K5!";V
* @param totalPage
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* The totalPage to set. m|[\F#+C
*/ 56Sh
publicvoid setTotalPage(int totalPage){ U~{Sa+
this.totalPage = totalPage; QT1:>k
} !K3i-zY
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} #)_J)/h
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上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 ,VKQRmd
2q"_^deI5*
个PageUtil,负责对Page对象进行构造: z}>4,d
java代码: |h^K M
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/*Created on 2005-4-14*/ 09R,'QJ|
package org.flyware.util.page; \R8 6;9ov
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import org.apache.commons.logging.Log; kF+ZW%6N
import org.apache.commons.logging.LogFactory; ,'FD}yw4v
0=OD?48<
/** C!!mOAhJ
* @author Joa tCWJSi`IJ
* J#6LSD@(O
*/ `aO.=:O_
publicclass PageUtil { _/|8%])
g9DG=\*A
privatestaticfinal Log logger = LogFactory.getLog sL)Rg(rkx
UG6M9
(PageUtil.class); &}zRH}s;
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/** {hxW,mmA
* Use the origin page to create a new page NmjzDN
* @param page %z1{Kus
* @param totalRecords M|U';2hZN:
* @return q z=yMIy=
*/ e@[9C(5E"
publicstatic Page createPage(Page page, int Nt HbwU,
v-ThdE$G#
totalRecords){ )nhfkW=e
return createPage(page.getEveryPage(), c2/FHI0J;
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page.getCurrentPage(), totalRecords); ]a)IMIh;
} BApa^j\?
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/** /[0F6
* the basic page utils not including exception ?4:rP@
O-Dc[t%
handler fzl=d_
* @param everyPage -eUV`&[4
* @param currentPage pXssh
* @param totalRecords /;DjJpwf0
* @return page o5>/}wIf
*/ 8AryIgy>@
publicstatic Page createPage(int everyPage, int rWJ*e Y
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currentPage, int totalRecords){ \F[n`C"Is
everyPage = getEveryPage(everyPage); NP "ylMr7P
currentPage = getCurrentPage(currentPage); gTnS[
int beginIndex = getBeginIndex(everyPage, M]1;
Q]/B/
currentPage); rrAqI$6
int totalPage = getTotalPage(everyPage, 6Hda]y
1f<RyAE?5
totalRecords); B9}E
{)T?
boolean hasNextPage = hasNextPage(currentPage, ikr7DBLt
.`Sw,XL5
totalPage); |IAW{_9)U
boolean hasPrePage = hasPrePage(currentPage); {b2 aL7
p/N 62G
returnnew Page(hasPrePage, hasNextPage, mdaYYD=c%
everyPage, totalPage, uNy!<u
currentPage, V(r`.75
]Ym=+lgi
beginIndex); -rO*7HO
} B_cgWJ*4
@O'I)(To
privatestaticint getEveryPage(int everyPage){ !j{CuA/
return everyPage == 0 ? 10 : everyPage; OMvT;Vgg
} LaclC]yLU
e9lOk)`t
privatestaticint getCurrentPage(int currentPage){ D!S8oKW
return currentPage == 0 ? 1 : currentPage; 7x(v?
} 3+%nn+m
^(DL+r,
privatestaticint getBeginIndex(int everyPage, int 3
&Sp@,
JDKLKHOMZ
currentPage){ !O 8.#+
return(currentPage - 1) * everyPage; {<!hlB
} wh*:\_!0\
a}dw9wU!:
privatestaticint getTotalPage(int everyPage, int **n y!
3[.3dy7,Z
totalRecords){ W/=7jM
int totalPage = 0; n_}aZB3;U
qEZ!2R^`G
if(totalRecords % everyPage == 0) >O3IfS(l
totalPage = totalRecords / everyPage; :Pf>Z? /d
else vbaC+AiX
totalPage = totalRecords / everyPage + 1 ; f]]f85
aDh|48}X
return totalPage; i(Vm!Y82
} &}E:jt}
v1h.pbz`w
privatestaticboolean hasPrePage(int currentPage){ i?x$w{co
return currentPage == 1 ? false : true;
w{r8kH
} ##GY<\",;
?9Ma^C;}
privatestaticboolean hasNextPage(int currentPage, (2tH"I
;Gh>44UM[
int totalPage){ #N$9u"8C
return currentPage == totalPage || totalPage == <%&_#<C)
UBIIo'u
0 ? false : true; gvlFumg2
} Bq;1^gtpe
F 3s?&T)[G
.:N:p We
}
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fbV@= (y?
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WN\PX!K9
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 MyFCJJ/
h7*O.Opm=
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 SiR\a!, C
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做法如下: EZ{\D!_Y
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 a'A s
OpUA{P
的信息,和一个结果集List: A2BRbwr>
java代码: |6*Va%LYO-
aj
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}x
/*Created on 2005-6-13*/ }I'^./za
package com.adt.bo; XWXr0>!,?
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import java.util.List; E-F5y
&mdB\Y?^
import org.flyware.util.page.Page; [xf$VkjuF
*(Ro;?O,pi
/** C=[Ae,
* @author Joa u>}zm_
*/ ZPvf-PqJl
publicclass Result { &?r*p0MQC
0Z8/R
private Page page; QoseS/
#D0W7a
private List content; GMe0;StT
[S) G$JW
/** H`gb}?9R
* The default constructor ;j!UY.i
*/ X|Dpt2A=
public Result(){ ?S9Nm~vlt
super(); FJF3B)Va|
} Y$+QNi
[Xq<EEb
/** Z/c_kf[
* The constructor using fields #<]Iz'\`
* FR["e1<0
* @param page y+RRg[6|
* @param content &+]x;K
*/ OGGSS&5tw
public Result(Page page, List content){ N3Z@cp
this.page = page; UO1$UF!
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this.content = content; ;:?*t{r4#
} + ~~ Z0.[
}7Jp :. qk
/** BCBU b
* @return Returns the content. w?S8@|MK
*/ 1@@y]s_.a
publicList getContent(){ )vQNiik#
return content; O{nC^`X
} >Zo-wYG
ng
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/** T\fudmj&
* @return Returns the page. RQ|?Ce",
*/
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public Page getPage(){ A6Q c;v+
return page; $ hoYkA
} s.KOBNCFa
/cYk+c
/** @2?=3Wf
* @param content r_q~'r35 _
* The content to set. A(NEWO
*/ nSS}%&a:LX
public void setContent(List content){ 0f{IE@-b
this.content = content; 5c)wZ
} 7>
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t"tNtLI
/** R@&?i=gk
* @param page gkLr]zv
* The page to set. }FZp840
*/ 9T/<x-FD
publicvoid setPage(Page page){
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this.page = page; 9c%(]Rn:
} pRmE ryR(U
} sE}sE=\
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oR7 7`
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aK-N}T
2. 编写业务逻辑接口,并实现它(UserManager, (KZUvsS k
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UserManagerImpl) >[hrJn[
java代码: >
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rtoSCj:
/*Created on 2005-7-15*/ ]2g5Ka[>w
package com.adt.service; JW2W>6Dgv[
5t TLMZ `o
import net.sf.hibernate.HibernateException; V.+DP
gZ=)qT]Pj
import org.flyware.util.page.Page; <x ^IwS
YK7gd|LR]
import com.adt.bo.Result; |I4D(#w.
=xl7vHn7
/** s8C:QC
* @author Joa +HYN$>
*/ zv>ZrFl*
publicinterface UserManager { 54bF)<+
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public Result listUser(Page page)throws TZ)(ZKX*R
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HibernateException; _ak.G=
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} uHTKo(NG
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java代码: a>#d=.
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zS#f%{
/*Created on 2005-7-15*/ iG?w;
package com.adt.service.impl; WlF+unB!9
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import java.util.List; d{vc
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import net.sf.hibernate.HibernateException; eG a#$x?.
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import org.flyware.util.page.Page; rcD.P?"
import org.flyware.util.page.PageUtil; +-xSuR,
n3-GnVC][
import com.adt.bo.Result; w-{#6/<kI5
import com.adt.dao.UserDAO; 3 LZL!^ 5N
import com.adt.exception.ObjectNotFoundException; r? 6Z1
import com.adt.service.UserManager; ~)oWSo5ll
f=-!2#%
/**
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* @author Joa 98"z0nI%
*/ _"FbjQ"
publicclass UserManagerImpl implements UserManager { *)}Ap4[
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private UserDAO userDAO; o}j_eHl{
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/** 9g<_JcN
* @param userDAO The userDAO to set. 3\+[38 _
*/ Q}k_#w
publicvoid setUserDAO(UserDAO userDAO){ O4'kS
@
this.userDAO = userDAO; 8_sU8q*s
} "OlI-^y
^HOwN<}`#
/* (non-Javadoc) @ B}c4,
* @see com.adt.service.UserManager#listUser iPtm@f,bI
q^T&A[hMPx
(org.flyware.util.page.Page) gn4g 43
*/ 'w |s*5
public Result listUser(Page page)throws ,i$(yx?
<W^XSk
HibernateException, ObjectNotFoundException { (pRy1DH~
int totalRecords = userDAO.getUserCount(); [h2p8i'o
if(totalRecords == 0) #7cf 8y
throw new ObjectNotFoundException cE_Xo.:Y,
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("userNotExist"); eL]w' }\
page = PageUtil.createPage(page, totalRecords); (0+ GLI8
List users = userDAO.getUserByPage(page); D=pI'5&
returnnew Result(page, users); ^QHMN 7r/
} Rp4BU"&sU
j_YZ(: =
}
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cvLcre% >A
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 [b)K@Ha
Kw5+4R(5
询,接下来编写UserDAO的代码: Z({`9+/>u
3. UserDAO 和 UserDAOImpl: 80l3.z,:
java代码: EF7|%N
'=G<)z@k
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/*Created on 2005-7-15*/ uvK%d\d
package com.adt.dao; X:} 5L>'
]6c2[r?g{
import java.util.List; BX)cV
b3HTCO-,fC
import org.flyware.util.page.Page; yKk,);
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import net.sf.hibernate.HibernateException; }?ac<> u&
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/** HDXjH|of
* @author Joa bU +eJU_%
*/ Qre&N_
publicinterface UserDAO extends BaseDAO { H f mMf^c
$R#L@iL-
publicList getUserByName(String name)throws @snLE?g j
fm2M i~}0
HibernateException; ,9j:h)ks?
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publicint getUserCount()throws HibernateException; @^4M~F%
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publicList getUserByPage(Page page)throws R8W44I*R:
s$y#Ufz
HibernateException; z{M,2
arH\QPaka'
} l$~bkVNL
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DO,&Foh\
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*L8HC8IbH
java代码: 0*M}QXt
5nIlG
fvfVBk#
/*Created on 2005-7-15*/ "9T`3cM0
package com.adt.dao.impl; Jt,
4@
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import java.util.List; I\6<)2j/L
`Q^Sm`R
import org.flyware.util.page.Page; eu|q
{p
J#Ehx|
import net.sf.hibernate.HibernateException; ->9xw
import net.sf.hibernate.Query; YqCK#zT/
/g7?,/vnZ
import com.adt.dao.UserDAO; k_^/
'
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/** X',0MBQ0
* @author Joa S&)
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*/ 0!\q
public class UserDAOImpl extends BaseDAOHibernateImpl R'HA>?D
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implements UserDAO { O7*i;$!R
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/* (non-Javadoc) yC*B OJS
* @see com.adt.dao.UserDAO#getUserByName 8mddI
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(java.lang.String) n
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*/ |^{" 2l"j
publicList getUserByName(String name)throws ZTC1t_
]7
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HibernateException { w o9f99
String querySentence = "FROM user in class )#Bfd(F
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com.adt.po.User WHERE user.name=:name"; Dx)XC?'xO
Query query = getSession().createQuery )Dpt<}}\
ZU'^%)6~o~
(querySentence); eakIK+-21y
query.setParameter("name", name); ,X6j$YLWp
return query.list(); bj{f[nZ d
} Mwk_SCy
vBnHG-5;P
/* (non-Javadoc) s\R?@
* @see com.adt.dao.UserDAO#getUserCount() gP%!
*/ [&V%rhi
publicint getUserCount()throws HibernateException { .LHe*J C
int count = 0; zD-8#H35X"
String querySentence = "SELECT count(*) FROM f`rz)C03
3<V!y&a
user in class com.adt.po.User"; AE
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Query query = getSession().createQuery !S{<Xc'wv
EBLoRW=8ld
(querySentence); z59J=?|
count = ((Integer)query.iterate().next _S1uJ~j;E
FR"^?z?}p
()).intValue(); pjM|}i<'Q
return count; Or>[_3
} B[V=l<J
1X.1t^HH:
/* (non-Javadoc) S}O\<6&
* @see com.adt.dao.UserDAO#getUserByPage tn1aH
+
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(org.flyware.util.page.Page) mX_`rvYII
*/ JqZ5DjI:
publicList getUserByPage(Page page)throws %L.+r!.
k({8C`&tK/
HibernateException { :[3\jLrc
String querySentence = "FROM user in class 8ipLq`)
)_?$B6hf,&
com.adt.po.User"; 9Z
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Query query = getSession().createQuery zY-m]7Yf
>m!.l{*j>N
(querySentence); =T]OYk
query.setFirstResult(page.getBeginIndex()) -AQX-[B
.setMaxResults(page.getEveryPage()); ?|dz"=y
return query.list(); OpQa!
} eGil`:JY"
rg~CF<
} Qrh9JFqdG6
H_FhHX.2(
9n'p 7(s%
OLwxGRYX
tS7u#YMh
至此,一个完整的分页程序完成。前台的只需要调用 #v-!GK_<
ND>}t#^$
userManager.listUser(page)即可得到一个Page对象和结果集对象 (Q+3aEUE
4KnDXQ%
的综合体,而传入的参数page对象则可以由前台传入,如果用 Zpmy)W]1
8^lXM-G-
webwork,甚至可以直接在配置文件中指定。 _?ZT[t<
*&D=]fG
下面给出一个webwork调用示例: ($kwlj~c
java代码: lLhCk>a
2 OTpGl
guvQISQlY
/*Created on 2005-6-17*/ j^.P=;
package com.adt.action.user; O]>`B{
./d ( @@
import java.util.List; V|)>
5z_)
import org.apache.commons.logging.Log; "^H+A-R[
import org.apache.commons.logging.LogFactory; $m>e!P>%u
import org.flyware.util.page.Page; ?6dtvz;K+?
]Gr'Bt /
import com.adt.bo.Result; &ly[mBP~
import com.adt.service.UserService; iYf4 /1IG,
import com.opensymphony.xwork.Action; ,#G@ri:B
ARE~jzakg
/** /Q!F/HY3ZS
* @author Joa L*z;-,
*/ ($wYawz
publicclass ListUser implementsAction{ C N"c
c nzPq\
privatestaticfinal Log logger = LogFactory.getLog IQDWH/c
R|suBF3
(ListUser.class); i]nE86.;
m{*l6`dF
private UserService userService; HIF]c
,J|};s+
private Page page; *s^5BLI9
gJ])A7O
privateList users; wb}tN7~Y;
so7;h$h!H
/* J: LSGj;R
* (non-Javadoc) L6a8%%`
* CqoL5qt
* @see com.opensymphony.xwork.Action#execute() $3L7R
*/ f_7p.H6\
publicString execute()throwsException{ JI^w1I, T
Result result = userService.listUser(page); x\jHk}Buj
page = result.getPage(); 3
*G=U
users = result.getContent(); gDsZbmR
return SUCCESS; "rXGXQu
} [D t`@Dm
MiC&av
/** qb_V
,b9
* @return Returns the page. g5E]o)
*/ 8X%;29tow
public Page getPage(){ ql#K72s
return page; nXN0~,+
} v zn/waw
>eC^]#c
/**
={fi&j
* @return Returns the users. Cxh9rUe.
*/ =3"Nn4Z
publicList getUsers(){ s#Le`pGoW
return users; '~@WJKk
} ;'h7
j*6
u(BYRB
/** 1t)6wk
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* @param page ;7hf'k
* The page to set. 4uz\Me(
*/ v uJ~Lg{
publicvoid setPage(Page page){ 4 QDW}5xB
this.page = page; D1w_Vpz
} M6e"4Gh
?FA:K0H?zl
/** ';1
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* @param users 34oC285yc
* The users to set. n\ IVpgP
*/ D^A_ 0@
publicvoid setUsers(List users){ P`"dj@1'
this.users = users; mb&b