Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 jO/cdLKX(
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 s7HKgj
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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 t|V<K^
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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 )0/*j]Kf
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分页支持类: i]N<xcF9N*
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java代码: Ep;i],}
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package com.javaeye.common.util; L"/?[B":
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import java.util.List; BWvM~no
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publicclass PaginationSupport { %)r:!R~R
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publicfinalstaticint PAGESIZE = 30; 4H(8BNgzV
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privateint pageSize = PAGESIZE; ErJ/h?+
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privateList items; NmXRA(m
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privateint totalCount; h=,hYz?]
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privateint[] indexes = newint[0]; 7K
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privateint startIndex = 0; /8Y8-&K0
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public PaginationSupport(List items, int B`<}YVA
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totalCount){ uS,?oS
setPageSize(PAGESIZE); u:lBFVqk
setTotalCount(totalCount); ?d3FR!
setItems(items); $~G5s<r
setStartIndex(0); Xz^k.4 Y{4
} iN.
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public PaginationSupport(List items, int ~?Vo d|>
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totalCount, int startIndex){ auc:|?H~1n
setPageSize(PAGESIZE); R6BbkYWrX
setTotalCount(totalCount); #^r-D[/m
setItems(items); [8UZ5_1W L
setStartIndex(startIndex); 0 K#|11r
} C3Q #[
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public PaginationSupport(List items, int ]7cciob
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totalCount, int pageSize, int startIndex){ ?4U4o<
setPageSize(pageSize); S*=^I2;
setTotalCount(totalCount); |" WL
setItems(items); S9P({iZK
setStartIndex(startIndex); oJ
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} >qB`03>
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publicList getItems(){ F<4:P=
return items; yna!L@ *@,
} JZ`SV}\`
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publicvoid setItems(List items){ krFp q;
this.items = items; |f @A-d X
} u9|Eos i
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publicint getPageSize(){ C5-u86F
return pageSize; >oWPwXA
} 8^+|I,
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publicvoid setPageSize(int pageSize){ ]o]`X$n
this.pageSize = pageSize; .pWRV<25
} b#p0s?*
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publicint getTotalCount(){ 7Z`4Kdh .
return totalCount; a'|]_`36x
} &Pm@+ML*x
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publicvoid setTotalCount(int totalCount){ WN{8gL&y
if(totalCount > 0){ ^8~TsK~
this.totalCount = totalCount; PdVx&BL*
int count = totalCount / ?i0+h7=6
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9
pageSize; PvV\b<Pe+
if(totalCount % pageSize > 0) rgCC3TX
count++; /klo),|&
indexes = newint[count]; zO\_^A|8H
for(int i = 0; i < count; i++){ Bj2iYk_cLa
indexes = pageSize * !{CIP`P1
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} W|@SXO)DY
}else{ 72xf|s=
this.totalCount = 0; g]HWaFjc5
} S+[,\>pY
} ]^.`}Y=`g
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publicint[] getIndexes(){ .wd7^wI^S
return indexes; Bf00&PE;
} 2= ;ZJ
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publicvoid setIndexes(int[] indexes){ ";(m,if-
this.indexes = indexes; >S`=~4
} @w= =*.x
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publicint getStartIndex(){ paD[4L?4Hk
return startIndex; fgtwVji
} aC1 xt(
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publicvoid setStartIndex(int startIndex){ M5+R8ttc
if(totalCount <= 0) =/|GWQj
this.startIndex = 0; #S/~1{
elseif(startIndex >= totalCount) hlV(jz
this.startIndex = indexes *8a[M{-X
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[indexes.length - 1]; c/bT5TIEWs
elseif(startIndex < 0) C $])q`9
this.startIndex = 0; u;^H =7R
else{ [= E=H*j
this.startIndex = indexes vFJ4`Gjw(
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[startIndex / pageSize]; 8q9^
} w/o8R3F
}
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publicint getNextIndex(){ YGChVROG~
int nextIndex = getStartIndex() + D&mPYxXL
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pageSize; L!33`xef'
if(nextIndex >= totalCount) [*)2Ou
return getStartIndex(); 4jZt0
else u SZfim@Z7
return nextIndex; i`CNgScF>
} ?UflK
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publicint getPreviousIndex(){ Z%.Ld2Q{
int previousIndex = getStartIndex() - x?{l<mc
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pageSize; L67yL( d6a
if(previousIndex < 0) l@UF-n~[
return0; >/C,1}p[
else 9} C(M?d
return previousIndex; L)|hjpQ
} {yf,:5
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} T` v
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抽象业务类 Qx EmuiN
java代码: O&.gc p!
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/** 0""%@X]m
* Created on 2005-7-12 0\ j)!b
*/ cru&nH*O^
package com.javaeye.common.business; QB*AQ5-
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import java.io.Serializable; ?5d[BV
import java.util.List; Pvkr$ou
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import org.hibernate.Criteria; wjID*s[
import org.hibernate.HibernateException; 9WoTo ,q
import org.hibernate.Session; J{uqbrJICr
import org.hibernate.criterion.DetachedCriteria; "el3mloR8
import org.hibernate.criterion.Projections; $Ovq}Rexc
import K^AIqL8
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org.springframework.orm.hibernate3.HibernateCallback; <3k9 y^0
import \@6w;tyi
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org.springframework.orm.hibernate3.support.HibernateDaoS i"!j:YEo
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upport; J(,gLl
}`$({\^w
import com.javaeye.common.util.PaginationSupport; M|z4Dy
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public abstract class AbstractManager extends x*^)B~7}
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HibernateDaoSupport { GV)DLHiyxX
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privateboolean cacheQueries = false; c&L|e$C]
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privateString queryCacheRegion; b Oh[(O!
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publicvoid setCacheQueries(boolean Xdf;'|HO
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cacheQueries){ J]*?_>"#8
this.cacheQueries = cacheQueries; ;2eZa|M*q
} `@ Ont+
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publicvoid setQueryCacheRegion(String ~m7?:(/lb
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queryCacheRegion){ )!`>Q|]}Zd
this.queryCacheRegion = 6O'B:5~[2
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queryCacheRegion; ^zS|O]Tx
} ~ln96*)M;
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publicvoid save(finalObject entity){ x5W@zqj
getHibernateTemplate().save(entity); RjR
} i'Q 4touy
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publicvoid persist(finalObject entity){ !Ie={BpzbZ
getHibernateTemplate().save(entity); SC0_ h(zb,
} xb(y15R\I
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publicvoid update(finalObject entity){ 6$$ku
getHibernateTemplate().update(entity); :"oUnBY%
} /{X2:g {
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publicvoid delete(finalObject entity){ pXxpEv
getHibernateTemplate().delete(entity); #J
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} pB]+c%\
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publicObject load(finalClass entity, !RdubM
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finalSerializable id){ ..ht)Gex
return getHibernateTemplate().load p8u-3
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(entity, id); RT=(vq @
} L/J)OJe\
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publicObject get(finalClass entity, e~BUAz
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finalSerializable id){ Q pbzx/2h
return getHibernateTemplate().get NA8$G|.?
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(entity, id); mOi 8W,2
} {BJn9B
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publicList findAll(finalClass entity){ f9&po2Pzf
return getHibernateTemplate().find("from 6m{1im=
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" + entity.getName()); .
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} !"x&tF
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publicList findByNamedQuery(finalString IOOAaa @(
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namedQuery){ .Cf`D tK
return getHibernateTemplate -}*YfwK
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().findByNamedQuery(namedQuery); lAPvphO
} L9)nRV8
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publicList findByNamedQuery(finalString query, js\|xfDxP
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finalObject parameter){ wi/dR}*A
return getHibernateTemplate jPNm $Y1
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().findByNamedQuery(query, parameter); pO_L,~<
} J'>i3eLq
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publicList findByNamedQuery(finalString query, n~NOqvT <
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finalObject[] parameters){ g!`$bF=e
return getHibernateTemplate T"$yh2tSY
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().findByNamedQuery(query, parameters); &ahZ_9Q
} !,< )y}L^)
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publicList find(finalString query){ hzjEO2
return getHibernateTemplate().find 2aUy1*aM
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(query); `by\@xQ)
} SBBi"U:
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publicList find(finalString query, finalObject Bzw!,(u/
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parameter){ xui.63/
return getHibernateTemplate().find 0
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(query, parameter); 8E|
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} >1Y',0v
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public PaginationSupport findPageByCriteria HsGyNkr?r
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(final DetachedCriteria detachedCriteria){ ,!s;o6|*y
return findPageByCriteria \We\*7^E
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); sSMcF[]@2I
} }QL 2#R
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public PaginationSupport findPageByCriteria !5P\5WF~Y
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(final DetachedCriteria detachedCriteria, finalint 'bXm,Ed
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startIndex){ f|f9[h'
return findPageByCriteria ,NQucp
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(detachedCriteria, PaginationSupport.PAGESIZE, b!R\ u1b
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startIndex); 5@6%/='I q
} Wm/0Y'$r&k
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public PaginationSupport findPageByCriteria ul$^]ZWkI
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(final DetachedCriteria detachedCriteria, finalint yqm^4)Dp
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pageSize, A@X&dy
finalint startIndex){ .*N,x0B(
return(PaginationSupport) ~EVD NnHEr
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getHibernateTemplate().execute(new HibernateCallback(){ j~eYq
publicObject doInHibernate 6mnj!p]3
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(Session session)throws HibernateException { R)3P"sGuN
Criteria criteria = rVx%"_'*-
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detachedCriteria.getExecutableCriteria(session); i%8I (F
int totalCount = w>:~Ev]
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((Integer) criteria.setProjection(Projections.rowCount tf?u ;n
\)=X=yn2
()).uniqueResult()).intValue(); ]F5qXF5
criteria.setProjection 5{Xld,zw
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(null); DL5`A?/
List items = <wt#m`Za
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criteria.setFirstResult(startIndex).setMaxResults Z)6gh{B08
s!Xj'H7K
(pageSize).list(); ]}_@!F)
PaginationSupport ps = J?WT
Z^w}: {
new PaginationSupport(items, totalCount, pageSize, 5h9`lS2
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startIndex); <m"yPi3TY
return ps; MZGN,[~)6
} {CM%QMM
}, true); I@ l'Fx
} p4
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public List findAllByCriteria(final =rV*iLy
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DetachedCriteria detachedCriteria){ h\k!X/
return(List) getHibernateTemplate ef\Pu\'U
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().execute(new HibernateCallback(){ \dAh^B K1(
publicObject doInHibernate )&"l3*x
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(Session session)throws HibernateException { U5;
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Criteria criteria = OTA @4~{C
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detachedCriteria.getExecutableCriteria(session); 85rXm*Df
return criteria.list(); e7f3dqn0
} E?o1&(2p
}, true); 28u)q2s^W|
} A7*<,]qT
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public int getCountByCriteria(final Ux~rBv''
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DetachedCriteria detachedCriteria){ j$ h.V#1z
Integer count = (Integer) X6jW mo8]
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getHibernateTemplate().execute(new HibernateCallback(){ Y%v?ROql
publicObject doInHibernate z116i?7EnV
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(Session session)throws HibernateException { )_P|_(
Criteria criteria = sgdxr!1?y
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detachedCriteria.getExecutableCriteria(session); qEC-'sl<
return U^trZ])
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criteria.setProjection(Projections.rowCount S) /(~
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()).uniqueResult(); eHCLENLmB
} G992{B
}, true); !/W[6'M#p
return count.intValue(); *ip2|2G$
} @EZ@X/8{&
} 5Z]zul@+*
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用户在web层构造查询条件detachedCriteria,和可选的 c:0nOP
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 {_0m0
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PaginationSupport的实例ps。 `+_UG^aeW
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ps.getItems()得到已分页好的结果集 eMk?#&a)
ps.getIndexes()得到分页索引的数组 D9
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ps.getTotalCount()得到总结果数 rPVz!(;k
ps.getStartIndex()当前分页索引 p\]Mf#B
ps.getNextIndex()下一页索引 *NdSL
ps.getPreviousIndex()上一页索引 `y5?lS*
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 P?GHcq$\
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,尤其是上面的示例代码,让我着实觉得该对我原来的分页查询做 m6J7)Wp
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一下代码重构了。 Az.(tJ X"
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我把原本我的做法也提供出来供大家讨论吧: n?vw|'(}
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首先,为了实现分页查询,我封装了一个Page类: \}SA{)
java代码: 8)IpQG
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/*Created on 2005-4-14*/ xc[LbaBG
package org.flyware.util.page; pPt7M'uL"
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/** g4,>cqRkq
* @author Joa ?N2/;u>
* %~ uMa
*/ n82N@z<8]
publicclass Page { 8Fy$'Zx'
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/** imply if the page has previous page */ 9%e&Z'l
privateboolean hasPrePage; >S4klW=*I
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/** imply if the page has next page */ LaL.C^K
privateboolean hasNextPage; o7"2"(
=>
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/** the number of every page */ ?bwF$Ku
privateint everyPage; O,(p><k$/
Ox ;q +5
/** the total page number */ f\O)+Vc
privateint totalPage; \ .HX7v
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/** the number of current page */ 1vlRzkd
privateint currentPage; __HPwOCG7
c e`3&
/** the begin index of the records by the current qMT7g LB'1
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query */ B9IqX
privateint beginIndex; }t!,{ZryE1
a nK7j2
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/** The default constructor */ 8x$BbK
public Page(){ \ FW{&X9a
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} ssVO+
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/** construct the page by everyPage t5dk}sRF
* @param everyPage MQc|j'vEY
* */ fpbb <Ro
public Page(int everyPage){ '"C$E922
this.everyPage = everyPage; xE(VyyR
} q{/>hvl
v'Y)~Kv@!
/** The whole constructor */ pE{ZWW[@+
public Page(boolean hasPrePage, boolean hasNextPage, n_5m+
1N
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)rJ{}U:S
int everyPage, int totalPage, l$KC\$?%*
int currentPage, int beginIndex){ T1TKwU8l
this.hasPrePage = hasPrePage; b X.S`
this.hasNextPage = hasNextPage; a f[<[2pma
this.everyPage = everyPage; QI*Y7R~<
this.totalPage = totalPage; v;.7-9c*
this.currentPage = currentPage; kL;sA'I:S
this.beginIndex = beginIndex; [4uTp[U!r
} <4,hrx&.
,4$ZB(\
/** L{fKZ
* @return r )8[LN-
* Returns the beginIndex. `I+G7KK
*/ 3=w$1.B d
publicint getBeginIndex(){ vZj:\geV
return beginIndex; 6 R}]RuFQ
} JSXudz5c
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/** j'Ry.8}
* @param beginIndex "&;>l<V
* The beginIndex to set. BS<5b*wG
*/ \6A-eWIQif
publicvoid setBeginIndex(int beginIndex){ + v. I|c
this.beginIndex = beginIndex; M\5aJ:cQ+
} TJS/ O~=
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/** lUWX[,
* @return |^jl^oW
* Returns the currentPage. #"{wm
*/ N)Fy#6
publicint getCurrentPage(){ wi'CBfr'z
return currentPage; \T)2J|mW
} "~~Js~
JWhi*je
/** TR:V7d
* @param currentPage 9W3zcL8
* The currentPage to set. wc7gOrPpm
*/ 7J@iJW],,
publicvoid setCurrentPage(int currentPage){ g?,\bmH E
this.currentPage = currentPage; 7b7~D +b
} _t[RHrs
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/** ]A oRK=aH
* @return 3!_X FV
* Returns the everyPage. aewVq@ngq!
*/ 0k"n;:KM8
publicint getEveryPage(){ qcau(#I9.
return everyPage; )xgOl*D
} jd<`W
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/** QcBuUFf!c
* @param everyPage 5yPw[
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* The everyPage to set. Bw^*6P^l
*/ m\QUt ;
publicvoid setEveryPage(int everyPage){ rro92(y
this.everyPage = everyPage; O iRhp(
} f9FJ:?
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/** =6FA(R|QU
* @return 'Fi\Qk'D@
* Returns the hasNextPage. jWHv9XtW
*/ C3EQzr`
publicboolean getHasNextPage(){ ktlI(#\%
return hasNextPage; ~DYUI#x
} 64]_o/u5W4
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/** O$d z=)
* @param hasNextPage VF8pH<
* The hasNextPage to set. {%g]Ym=
*/ tkT:5O6
publicvoid setHasNextPage(boolean hasNextPage){ zN2CI6
this.hasNextPage = hasNextPage; mx`QBJ
} $ ?ayE
OW}ny
/** E=
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* @return -/ 5" Py
* Returns the hasPrePage. l":\@rm`
*/ qffVF|7
publicboolean getHasPrePage(){ fmqHWu*wG
return hasPrePage; z%ZAN-
} TmI~P+5w
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/** }HdibCAOf
* @param hasPrePage } a#RX$d&
* The hasPrePage to set. "u#,#z_
*/ Zb> UY8
publicvoid setHasPrePage(boolean hasPrePage){ )fPN6x/e
this.hasPrePage = hasPrePage; /2 V
} y5>X0tT
tf1iRXf8
/** 4:1URhE
* @return Returns the totalPage. Mn`);[
* TVy\%FP^L
*/ f]c{,LFvZ
publicint getTotalPage(){ 1 Hw %DJ
return totalPage; [2h4%{R&
} | ]#PF*
IIj
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/** 2G=prS`s
* @param totalPage ySkz5K+|g
* The totalPage to set. GYp}V0
*/ "d1~(0=6<m
publicvoid setTotalPage(int totalPage){ Cp!bsasj
this.totalPage = totalPage; jU~q~e7Te
} ,O`a_b]
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} VsIDd}~C%
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d@d\9*mn
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{,:yZ&(
上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 = Ob-'Syg>
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个PageUtil,负责对Page对象进行构造: Y)V)g9
java代码: w|t}.u
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/*Created on 2005-4-14*/ Veeuw
package org.flyware.util.page; [2*?b/q3J
_+B{n^ {
import org.apache.commons.logging.Log; ?$v*_*:2h
import org.apache.commons.logging.LogFactory; E@.daUoB
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/** O0`o0!=P
* @author Joa <m"fzT<"
* zDD
*/ zE,1zBS<
publicclass PageUtil { 7{W#i<W
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privatestaticfinal Log logger = LogFactory.getLog $[S)A0O
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(PageUtil.class); 2!kb?
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/** h#:_GNuF
* Use the origin page to create a new page L!| `IK
* @param page 8'<RPU}M
* @param totalRecords g#*LJ`1
* @return S{d]0
*/ (T65pP_P 7
publicstatic Page createPage(Page page, int ]a=n(`l?
lGhhH_
totalRecords){ uO^,N**R#
return createPage(page.getEveryPage(), 7T69tQZ<
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page.getCurrentPage(), totalRecords); .DrGr:UW
} Iz_#wO
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/** 6<t<hP_3O
* the basic page utils not including exception xI>HY9i)
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handler Pt=@U:
* @param everyPage /mK."5-cm
* @param currentPage )B$Uo,1
* @param totalRecords ^1w<wB\B
* @return page "wi}/,)
*/ prw% )#,
publicstatic Page createPage(int everyPage, int HrK7qLw7
+~n"@ /
currentPage, int totalRecords){ [wkSY>Gu
everyPage = getEveryPage(everyPage); q.:j
yj6
currentPage = getCurrentPage(currentPage); vp|.x |@
int beginIndex = getBeginIndex(everyPage, +*`>7m<^
k*u4N
currentPage); M+l~^E0Wj
int totalPage = getTotalPage(everyPage, 1lLXu
-IE=?23Do?
totalRecords); "2_nN]%u-
boolean hasNextPage = hasNextPage(currentPage, %|(Cb!ySX
=38c}(
totalPage);
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boolean hasPrePage = hasPrePage(currentPage); a/Ik^:>m
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returnnew Page(hasPrePage, hasNextPage, -Pp =)_O
everyPage, totalPage, :"Gd;~p.
currentPage, Sp-M:,H3H
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beginIndex); 19]O;
} `st^i$A
%) /Bl.{}<
privatestaticint getEveryPage(int everyPage){ 70F(`;
return everyPage == 0 ? 10 : everyPage; W<\*5oB%H
} X,`^z,M%I
mV;)V8'
privatestaticint getCurrentPage(int currentPage){ GhC%32F
return currentPage == 0 ? 1 : currentPage; ;s^F:O
} ^!7|B3`
m?y'Y`
privatestaticint getBeginIndex(int everyPage, int f>[!Zi*
QD*\zB
currentPage){ 5?HoCz]l
return(currentPage - 1) * everyPage; z^Y4:^L~I
} i*61i0
92D :!C
privatestaticint getTotalPage(int everyPage, int lEC91:Jyt
Ih_=yk
totalRecords){ )YPut.
int totalPage = 0; jmr1e).];
+5N09$f;R
if(totalRecords % everyPage == 0) 1Gp|_8
totalPage = totalRecords / everyPage; 5e
>qBw8t
else rPx:o}&<
totalPage = totalRecords / everyPage + 1 ; oV;I8;#\J
f-5}`)`.+
return totalPage; yv(\5)XF
} '/GZ/$a_l
0czEA
privatestaticboolean hasPrePage(int currentPage){ ia*Bcx_RW+
return currentPage == 1 ? false : true; h,x'-]q
} O[5u6heNMr
JL=s=9N;3
privatestaticboolean hasNextPage(int currentPage, 8z`Ne(h;
A)HV#T`N
int totalPage){ ;@/vKA3l.
return currentPage == totalPage || totalPage == iu+rg(*%
D8=a +!l-
0 ? false : true; #vPf$y6jCI
} iUOGuiP
[J6q(}f
4*?JU
v
} ^~DClZ
/9<62F@zJ"
WV,j
<x9w
Ixr#zt$T-G
icXeB_&cS
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 gVN&?`k*?
9._Osbp3P
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 WoDQg64
^ Iy'<J
做法如下: E-b3#\^:
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 &-(p~[|
9 UcSQ"D
的信息,和一个结果集List: #TD0)C/
java代码: !^IAn
x`Ik747^v
o]WG8Mo-
/*Created on 2005-6-13*/ X@^"@
package com.adt.bo; N6uKFQL:{
4L/8Hj#g
import java.util.List; (E<QA
/u pDbP.O
import org.flyware.util.page.Page; h%!N!\
YnwP\Arfq
/** 11BfJvs:
* @author Joa oWcBQ|
*/ \"=b8x
publicclass Result { k-|b{QZ8!;
O_|p{65
private Page page; EM0]"s@Lf
BLcsIyq
private List content; ?vocI
)jm u*D5N
/** 9p%8VDF=
* The default constructor {"@E_{\
*/ +^V%D!.$@
public Result(){ nI<Ab_EB
super(); |emZZj
} ]?n~?dD{]
j[&C6l+wH
/** Nh+ZSV4WJ:
* The constructor using fields .>+jtp}
* f}?q
* @param page A"no!AN
* @param content JTfG^Nv>K
*/ dx[kG
public Result(Page page, List content){
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this.page = page; .+2@(r
this.content = content; cP&XkAQ
} {,
zg
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/** 1`l10f qU
* @return Returns the content. WoX,F1 o
*/ ~JSa]6:_+
publicList getContent(){ 1xt N3{c
return content; ZY{zFg9
} ^laf!kIP
$ZfoJR]%
/** RMO6k bfP
* @return Returns the page. %N0cp@Vz
*/ 0Lki(
public Page getPage(){ Wz-7oP%;I
return page; B4ky%gF4
} 8jm\/?k|
-8D$ [@y(
/** =3<@{^Eg
* @param content N[8y+2SZ
* The content to set. ["
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*/ ?R\:6x<
public void setContent(List content){ dT4e[4l
this.content = content; Sp^jC
Xu
} iTg7@%
)\|Bghui
/** F]7$Y
* @param page (H-Y-Lk+
* The page to set. \ws^L,h
*/ Gw0MDV&[
publicvoid setPage(Page page){ /%5X:*:H
this.page = page; IiRII)
} {wyf>L0j
} 8
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{ZrB,yK
n>
O3p
~
t}2$no?
$ H2HVJ
2. 编写业务逻辑接口,并实现它(UserManager, (&ABfm/t
'k9dN
\ev
UserManagerImpl) OX*5 yT{
java代码: xXm:S{I
{ehAF=C
TWk1`1|
/*Created on 2005-7-15*/ kG70j{gf
package com.adt.service; [t}$W*hY
[Csv/
import net.sf.hibernate.HibernateException; Fu6~8uDV{{
CxW-lU3G`
import org.flyware.util.page.Page; 7d"gRM;
3^J~ts{*
import com.adt.bo.Result; kEpCF:@A
;^Y]nsd
/** ^lCQHz
* @author Joa F^)SQ%xx
*/ t ]yD95|
publicinterface UserManager { T{Rhn V1
c
DO<z
public Result listUser(Page page)throws dLIZ)16&
c<n <!!vi
HibernateException; -L)b;0%
-)2sR>`A%
} :KL5A1{
1xF<c<
qH-':|h7
H<bK9k)E
soi.`xE
java代码: BV`,~n:
0nV|(M0lu?
U*7Yi-"/*
/*Created on 2005-7-15*/ K
oF4e:2>
package com.adt.service.impl; m6D]
HLml:B[F(
import java.util.List; 69>N xr~k
KsMC+:`F
import net.sf.hibernate.HibernateException; 8wQ|Ep\
,@]rvI6x
import org.flyware.util.page.Page; E8QY6 gKF
import org.flyware.util.page.PageUtil; Hjtn*^fo^
,F)9{ <r]
import com.adt.bo.Result; t)hAD_sf
import com.adt.dao.UserDAO; :Kt'Fm,s?
import com.adt.exception.ObjectNotFoundException; hB:}0@l6p=
import com.adt.service.UserManager; aE'nW@YL.
GDMg.w4Yk
/** U`h> [9
* @author Joa pg;y\}
*/ 2|C(|fD4
publicclass UserManagerImpl implements UserManager { "/MA.zEl0,
v1Wz#oP
private UserDAO userDAO; PWw2;3`-6w
/5Zt4&r
/** MU/3**zoW
* @param userDAO The userDAO to set. _RcFV
*/ !^EdB}@yS
publicvoid setUserDAO(UserDAO userDAO){ bn8`$FA^
this.userDAO = userDAO; 'YaD=""
} [esR!})
$<N!2[I L
/* (non-Javadoc) _jr'A -M
* @see com.adt.service.UserManager#listUser ^Td_B03)
OKH4n/pq
(org.flyware.util.page.Page) MPg"n-g*
*/ ; OpN&q+
public Result listUser(Page page)throws CS<,qvLpL
}F~4+4B^
HibernateException, ObjectNotFoundException { mm,be.
int totalRecords = userDAO.getUserCount(); It
.`
if(totalRecords == 0) `43X? yQ
throw new ObjectNotFoundException YLEa;MR
a7Fc"s*
("userNotExist"); 6]*~!al?
page = PageUtil.createPage(page, totalRecords); ueM[&:g&MU
List users = userDAO.getUserByPage(page); }&{z-/;H
returnnew Result(page, users); I3wv6xZ2
} w6 x{<d
m)aNuQvy:Z
} :Vyr8+]
kA1C&
D<35FD,
ue;o:>G
' `K-rvF,C
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 apxY2oE&
P}kp_l27
询,接下来编写UserDAO的代码: |dxcEjcY_
3. UserDAO 和 UserDAOImpl: A&:i$`m,
java代码: 7kZ-`V|\.
3Wl,T5}{
]$VYzE2e
/*Created on 2005-7-15*/ uuA
q\YZy/
package com.adt.dao; ?tJyQT
2W_p)8t>b
import java.util.List; DG!H8^
S|pMX87R
import org.flyware.util.page.Page; \~:Uj~
AUk,sCxd
import net.sf.hibernate.HibernateException; 3i c6!T#t"
=QiVcw,G#
/** )t-Jc+*A>
* @author Joa wf=
s-C
*/ m<DiYxK
publicinterface UserDAO extends BaseDAO { W=9Zl(2C
]^j'2nJv0
publicList getUserByName(String name)throws \ tK{!v+
V*bX>D/
HibernateException; lOc!KZHUp
Y8^pgv
publicint getUserCount()throws HibernateException; OZ/!=;
keBf^NY
publicList getUserByPage(Page page)throws X}/{90UD
r[TTG0|
HibernateException; 7%E]E,f/#
D_HE!fl
} ia!b0*<
NPL(5@
;B'5B]A3
-666|pA
p..O;_U
java代码: z DP
.)zX<~,
Wx i|(}
/*Created on 2005-7-15*/ 4K(AXk
package com.adt.dao.impl; z/,qQVv=}4
1ud+~y$K
import java.util.List; 99\;jz7
?ep'R&NV
import org.flyware.util.page.Page; F>0[v|LG
UA{tmIC\
import net.sf.hibernate.HibernateException; U%7| iK
import net.sf.hibernate.Query; ~_z"So'|F_
nJvDk h#h1
import com.adt.dao.UserDAO; (L{Kg U&{$
XM+o e0:[
/** I.M@we/bR}
* @author Joa b* QRd
*/ /%#LA
public class UserDAOImpl extends BaseDAOHibernateImpl =`b/ip5
#DN5S#Ic
implements UserDAO { {x+"Ru~7,
^+ hJ& 9W
/* (non-Javadoc) m5G9
B-\?
* @see com.adt.dao.UserDAO#getUserByName T JB)]d<
<H Le,
(java.lang.String) *6-f vqCv
*/ X/
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publicList getUserByName(String name)throws g `)5g5
lE8M.ho\
HibernateException { Vu%XoI)<KY
String querySentence = "FROM user in class vBMuV pzO
Xy74D/ocui
com.adt.po.User WHERE user.name=:name"; \G3P[E[
Query query = getSession().createQuery j=%^CRum
hU}!:6G%[P
(querySentence); 98%M`WY
query.setParameter("name", name); :N826_q
return query.list(); 6(Qr!<
}
tj:Q]]\M
5,>Of~YN
/* (non-Javadoc) N34.Bt
* @see com.adt.dao.UserDAO#getUserCount() #SHmAB
*/ Xm|Uz`A;
publicint getUserCount()throws HibernateException { h "7:&=e
int count = 0; PJ=N.xf}
String querySentence = "SELECT count(*) FROM N(%%bHi#V
ii.L]#3y
user in class com.adt.po.User"; hrT_0FZV
Query query = getSession().createQuery %<g(EKl
6N%fJ
(querySentence); C)7T'[
count = ((Integer)query.iterate().next +B
4&$z
$#cZJ@;]
()).intValue(); YpAJ7E|7
return count; "k8Yc<`u
} b.`<T"y
;{n@hM*O
/* (non-Javadoc) eb])=
* @see com.adt.dao.UserDAO#getUserByPage NV|[.g=lg
6z/ct|n
(org.flyware.util.page.Page) %{fa
.>6
*/ G2bZl%
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publicList getUserByPage(Page page)throws RGeM.
:QndeUw
HibernateException { GTj=R$%09
String querySentence = "FROM user in class <K~> :4c
9 >t
com.adt.po.User"; 9@Iz:!oqb
Query query = getSession().createQuery '`-W!g[
>
NF}QQwG3
(querySentence); $[L8UUHY<8
query.setFirstResult(page.getBeginIndex()) $`2rtF
.setMaxResults(page.getEveryPage()); fZ9EE3
return query.list(); yqy5i{Y
} )yV|vn
19Cs
3B \4
} (RDY-~#~
}Htnhom0n
|Ef\B]Ns
n21Pfig
A9*( O)
至此,一个完整的分页程序完成。前台的只需要调用 [j6EzMN
4Y):d!'b
userManager.listUser(page)即可得到一个Page对象和结果集对象 W"m\|x
A@8Ot-t:\2
的综合体,而传入的参数page对象则可以由前台传入,如果用 ;XJK*QDN
r'kUU]j9
webwork,甚至可以直接在配置文件中指定。 cTA8F"UGD
Dq#/Uw#
下面给出一个webwork调用示例: SIJ:[=5!7
java代码: &GF|Rr8NXs
bIFKP
jV(\]g"/=
/*Created on 2005-6-17*/ >&@hm4
package com.adt.action.user; ZZkxEq+D
p2c4 <f-M
import java.util.List; 3:">]LMi
}{! #`'s
import org.apache.commons.logging.Log; 1v)X]nW
import org.apache.commons.logging.LogFactory; !]%M
import org.flyware.util.page.Page; a@|/D\C
R^}}-Dvr
import com.adt.bo.Result; G}o?lo\#h
import com.adt.service.UserService; i+/:^tc;
import com.opensymphony.xwork.Action; )Ir_:lk
$/\b`ID
/** T
;Ga G
* @author Joa W\(u1>lj
*/ +3HukoR(
publicclass ListUser implementsAction{ 4?#0fK
u!k]Q#2ZR
privatestaticfinal Log logger = LogFactory.getLog BrW1:2w
>\
;2o+|U@
(ListUser.class); pK)*{fC$`
IrAc&Eh