Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 51k^?5cO
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 N{<=s]I%x
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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 6n.W5
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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 t<6`?\Gk
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分页支持类: Tv&-n
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java代码: Q4_+3-g<7L
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package com.javaeye.common.util; I4Ys,n
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import java.util.List; y#3mc#)k
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publicclass PaginationSupport { 3JiDi
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publicfinalstaticint PAGESIZE = 30; u $N2uFc
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privateint pageSize = PAGESIZE; -O2ZrJ!q
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privateList items; xFpMn}CD
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privateint totalCount; JBCcR,\kM*
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privateint[] indexes = newint[0]; &P%3'c}G
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privateint startIndex = 0; GQTMQXn(
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public PaginationSupport(List items, int 9d4PH
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totalCount){ j5ZeYcQ-
setPageSize(PAGESIZE); Ctxs]S tU%
setTotalCount(totalCount); bmotR8d
setItems(items);
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setStartIndex(0); zxtx~XO
} Vt:]D?\3
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public PaginationSupport(List items, int yAoJ?<4^W
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totalCount, int startIndex){ Efb>ZQ
setPageSize(PAGESIZE); tm~V+t!mj
setTotalCount(totalCount); 4!<8Dd
setItems(items); 2l#Ogn`k
setStartIndex(startIndex); \iAkF`OC
} ewqfs/
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public PaginationSupport(List items, int _PrK6M@"L
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totalCount, int pageSize, int startIndex){ C`3}7qi|C
setPageSize(pageSize); ^ad
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setTotalCount(totalCount); *ta
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setItems(items); +?n81|7`
setStartIndex(startIndex); 7</&=lly
} D[m;rcl
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publicList getItems(){ TmG$Cjf84
return items; {%xwoMVc+
} M"2Tuwz
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publicvoid setItems(List items){ u-3A6Q
this.items = items; 0.C y4sH'
} F0%FX`b{{
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publicint getPageSize(){ FyX\S=
return pageSize; |BnjT*_9
} @Hj5ZJ
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publicvoid setPageSize(int pageSize){ 40N8?kQ}?
this.pageSize = pageSize; M ()&GlNs
} Y 9]
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publicint getTotalCount(){
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return totalCount; [s$vY~_
} ,qV8(`y_
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publicvoid setTotalCount(int totalCount){ Ub*Gv(Pg
if(totalCount > 0){ Juj"cjob
this.totalCount = totalCount; $-m@cObw!.
int count = totalCount / PI(;t9]b
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pageSize; ^AtAfVJN0
if(totalCount % pageSize > 0) )#zc$D^U
count++; ?9nuL}m!a
indexes = newint[count]; a}ogNx
for(int i = 0; i < count; i++){ eWSA
indexes = pageSize * fEE[huG
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} Tz3 L#0:j
}else{ 7J,j
this.totalCount = 0; n#Xi Co_\
} t7tX<|aN
} S/)P&V%
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publicint[] getIndexes(){ {/G~HoY1i
return indexes; &p=Uus
} [ZU6z?Pf
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publicvoid setIndexes(int[] indexes){ u )PB@
this.indexes = indexes; ?U.+SQ
} @ofivCc<%
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publicint getStartIndex(){ , f{<
return startIndex; SYd4 3PA
} |;e K5(|
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publicvoid setStartIndex(int startIndex){ 2 %UzCK
if(totalCount <= 0) [E<NEl*
this.startIndex = 0; "1|n]0BF
elseif(startIndex >= totalCount) VA+
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this.startIndex = indexes ekC
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[indexes.length - 1]; \Fg%V>
elseif(startIndex < 0) TG9 a1q
this.startIndex = 0; 5e=9~].7
else{ ? cU9~=
this.startIndex = indexes /W\@/b,
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[startIndex / pageSize]; @-=0T!/
} XE8>&&X
} ChzKwYDY
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publicint getNextIndex(){ `&y Qtj#
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int nextIndex = getStartIndex() + 2GeJ\1k
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pageSize; |j:"n3~6
if(nextIndex >= totalCount) EQ< qN<uW
return getStartIndex(); :"QR;O@
else E;m]RtvH
return nextIndex; \Gm$hTvB&
} Kz>bfq7
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publicint getPreviousIndex(){ $>^DkrOd
int previousIndex = getStartIndex() - &w15GO;4
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pageSize; xE>H:YPm
if(previousIndex < 0) Q8-;w{%
return0; 96G8B62
else J:W|2U="
return previousIndex; h[eC i
} 24{Tl
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} !@>_5p>q*
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抽象业务类 `Xs3^FJt
java代码: T0HNld
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/** FR*CiaD1
* Created on 2005-7-12 zEM c)
*/ #BPJRNXd
package com.javaeye.common.business; <'T:9
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import java.io.Serializable; tL#~U2K
import java.util.List; 5;v_?M!UCK
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import org.hibernate.Criteria; &,DZ0xA
import org.hibernate.HibernateException; F#b^l}
import org.hibernate.Session; Tumv0=q4wd
import org.hibernate.criterion.DetachedCriteria; y
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import org.hibernate.criterion.Projections; ]u5B]ZQnA
import 7{z\^R^O
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org.springframework.orm.hibernate3.HibernateCallback; d9=i{i3
import EKgY
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org.springframework.orm.hibernate3.support.HibernateDaoS we("#s1=
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upport; eW<|I
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import com.javaeye.common.util.PaginationSupport; +x!Hc
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public abstract class AbstractManager extends :QoW*Gs1
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HibernateDaoSupport { B}(r>8?dm
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privateboolean cacheQueries = false; QjlQsN!
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privateString queryCacheRegion; !jQj1QZR`
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publicvoid setCacheQueries(boolean WqO4_;X6/
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cacheQueries){ gf ?_tB0C
this.cacheQueries = cacheQueries; <da-iY\5
} T?g%I
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publicvoid setQueryCacheRegion(String P @Jo[J<
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queryCacheRegion){ eF"k"Ckt'
this.queryCacheRegion = 9oU1IT9
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queryCacheRegion; a.z)m}+
} Z35(f0b
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publicvoid save(finalObject entity){ 4{QD: D(D
getHibernateTemplate().save(entity); ID]E3K
} p:NIRs
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publicvoid persist(finalObject entity){ ],~H3u=s3
getHibernateTemplate().save(entity); 8w$q4fg0
} Fhrj$
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publicvoid update(finalObject entity){ i+Lqj
getHibernateTemplate().update(entity); tfCK^{
} RsW4 '5
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publicvoid delete(finalObject entity){ oCxy(q'y
getHibernateTemplate().delete(entity); #9glGPR(
} `aDVN_h{6
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publicObject load(finalClass entity, vD^Uod1
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finalSerializable id){ (nwp s
return getHibernateTemplate().load 3UX6 Y]E3
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(entity, id); u[HamGxx$u
} LP'wL6#
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publicObject get(finalClass entity, ^GS\(egt
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finalSerializable id){ 9$L2a
return getHibernateTemplate().get 9>@Vk
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(entity, id); ,1B`Ve
} !;U oZ~
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publicList findAll(finalClass entity){ *\Lr]6k
return getHibernateTemplate().find("from kEp{L
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" + entity.getName()); ^'n;W<\p)
} [a_o3
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publicList findByNamedQuery(finalString H*P[tyz$
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namedQuery){ YkbuyUui
return getHibernateTemplate i<(~J4}b
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().findByNamedQuery(namedQuery); "yc|ng
} ,n2"N5{jw
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publicList findByNamedQuery(finalString query, G+&pq
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finalObject parameter){ qLPuKIF
return getHibernateTemplate DYoGtks(
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().findByNamedQuery(query, parameter); LJ K0WWch
} cbYQ';{
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publicList findByNamedQuery(finalString query, H>Ucmd;ay
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finalObject[] parameters){ tH~>uOZW
return getHibernateTemplate M?AKJE j5
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().findByNamedQuery(query, parameters); Ldj*{t`5
} p:)=i"uL
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publicList find(finalString query){ kZ PL$\/A
return getHibernateTemplate().find 7xFZJ#
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(query); F+ 7*SImv6
} t
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publicList find(finalString query, finalObject D &@Iuo
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parameter){ &E1m{gB(
return getHibernateTemplate().find Yep~C%/}
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(query, parameter); V/:2xT
} (tX)r4VU
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public PaginationSupport findPageByCriteria t-5Y,}j
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(final DetachedCriteria detachedCriteria){ 0m=57c$O
return findPageByCriteria Ndmw/ae
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); B=$O4nW_b
} +KD7Di91<K
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public PaginationSupport findPageByCriteria ktS^^!,l%
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(final DetachedCriteria detachedCriteria, finalint nM Z)x-
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startIndex){ oH!O{pQK}
return findPageByCriteria 0\vG
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(detachedCriteria, PaginationSupport.PAGESIZE, &r~s3S{pQ
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startIndex); ,p OGT71
} FUlhEH
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public PaginationSupport findPageByCriteria D,R',(3
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(final DetachedCriteria detachedCriteria, finalint qv}ECQ
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pageSize, q5L^>"
finalint startIndex){ IVkB)9IW
return(PaginationSupport) 1DhC,)+D}q
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getHibernateTemplate().execute(new HibernateCallback(){ fU?#^Lg
publicObject doInHibernate {wsJ1v8!
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(Session session)throws HibernateException { w/(c}%v}=
Criteria criteria = Nh_\{
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detachedCriteria.getExecutableCriteria(session); Eu:/U*j
int totalCount = 1:<(Q2X%
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((Integer) criteria.setProjection(Projections.rowCount 5lJL[{
)\ceanS
()).uniqueResult()).intValue(); DKu$u ]Z
criteria.setProjection E:ci/09wD
fn=A_
i
(null); Q}OloA(+
List items = d+,!p8Q
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criteria.setFirstResult(startIndex).setMaxResults "n`z`{<n
.pQ5lK(R
(pageSize).list(); `6J7c;:
PaginationSupport ps = r6'dEa
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new PaginationSupport(items, totalCount, pageSize, )=d)j^t9
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startIndex); G^#>HE|
return ps; v-d"dC`
} E
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}, true); GT6i9*tb#
} H~nX!sO
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public List findAllByCriteria(final JJ
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DetachedCriteria detachedCriteria){ k[ z yR
return(List) getHibernateTemplate n}IGxum8`
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().execute(new HibernateCallback(){ (w)%2vZ^
publicObject doInHibernate [)s4:V
t^"8M6BqC;
(Session session)throws HibernateException { 9QXsbd6
Criteria criteria = #eOHe4Vt
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detachedCriteria.getExecutableCriteria(session); `|?<KF164
return criteria.list(); 'QG`^@Z
} W j^@Zq#
}, true); SfC* ZM}<
} UtTlJb{-j
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public int getCountByCriteria(final q%])dZ!lE
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DetachedCriteria detachedCriteria){ */aQ+%>jf
Integer count = (Integer) te-xhJ&K
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getHibernateTemplate().execute(new HibernateCallback(){ [BD`h
publicObject doInHibernate F&R*njJcc
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(Session session)throws HibernateException { SR?mSpq5
Criteria criteria = NL$z4m0
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detachedCriteria.getExecutableCriteria(session); E#:!&{O
return <hCO-r#
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criteria.setProjection(Projections.rowCount r/'!#7dLG-
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()).uniqueResult(); k-=lt\?
} 4bA^Gq
}, true); oio{@#DX`
return count.intValue(); w=;>
} A/I\MN|
} z6@8IszU
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用户在web层构造查询条件detachedCriteria,和可选的 4%~*}
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 Q&r.wV|
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PaginationSupport的实例ps。 ;X<Ez5v3
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ps.getItems()得到已分页好的结果集 T(x@gwc
ps.getIndexes()得到分页索引的数组 {f-O~P<Z4
ps.getTotalCount()得到总结果数 E8r6P:5d`
ps.getStartIndex()当前分页索引 }Mt)57rU
ps.getNextIndex()下一页索引 )m;*d7l~p
ps.getPreviousIndex()上一页索引 stajTN*J
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 v2rO>NY4
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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 3f^Pr
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一下代码重构了。 L#K`F8Wi=
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我把原本我的做法也提供出来供大家讨论吧: yYJ_;Va
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首先,为了实现分页查询,我封装了一个Page类: Up?RN %gq
java代码: I?PqWG!O
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/*Created on 2005-4-14*/ 46NuT]6/4
package org.flyware.util.page; =AzPAN#e
#&kj>
/** i#b /.oa
* @author Joa RN-gZ{AW
* *t| !xO
*/ %f&Y=
publicclass Page { 8Y`g$2SZ^8
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/** imply if the page has previous page */ !@Qk=Xkg
privateboolean hasPrePage; b/a\{
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/** imply if the page has next page */ nk tGO
privateboolean hasNextPage; bC:sd2s
].xSX0YQ%
/** the number of every page */ k)7i^1U
privateint everyPage; /jJD
{
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/** the total page number */ /5Qh*.(S
privateint totalPage; YRVh[Bqg`
r craf4%
/** the number of current page */ Vxap+<m
privateint currentPage; RBf#5VjOG!
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/** the begin index of the records by the current /xJD/"Y3&
&zy%_U2%
query */ Q/?`);
privateint beginIndex; {Ia1H
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/** The default constructor */
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public Page(){ D^O[_/i&
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} \u`P(fI!K%
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/** construct the page by everyPage id9QfJ9t
* @param everyPage ")MHP~ ?
* */ *B!Ox}CI.L
public Page(int everyPage){ >I4BysR
this.everyPage = everyPage; %HpPTjAW
} =nCA=-Jv
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i \
/** The whole constructor */ .TA)|df
^
public Page(boolean hasPrePage, boolean hasNextPage, of*T,MUI
.Xp,|T
n+sv2Wv:
int everyPage, int totalPage, WMC^G2 n
int currentPage, int beginIndex){ R4;1LZ8XzS
this.hasPrePage = hasPrePage; h?dSn:Y\?
this.hasNextPage = hasNextPage; xwsl$Rj
this.everyPage = everyPage; YQ:$m5ai
this.totalPage = totalPage; fpQFNV
this.currentPage = currentPage; d)uuA;n
this.beginIndex = beginIndex; 0-uj0"r`
} kIS )*_
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/** S>x@9$( ym
* @return m33&obSP
* Returns the beginIndex. Qc*p+N+$
*/ ?0X$ox
publicint getBeginIndex(){ bTeuOpp
return beginIndex; JzN "o'
} #0r^<Yn
QmSj6pB>
/** r&R~a9+)
* @param beginIndex [7.Num_L
* The beginIndex to set. >b\|%=(x!*
*/ ~\-=q^/!
publicvoid setBeginIndex(int beginIndex){ -<x%
this.beginIndex = beginIndex; y]{b4e
} r>8`gAhx
aoW2 c1`?Z
/** Hz,Gn9:p
* @return R-pON4D"*
* Returns the currentPage. `/m]K~~
*/ zZ-/S~l
publicint getCurrentPage(){ HkRvcX
5
return currentPage; y'>9'/&
} ("=q-6$G
qh>An;:u
/** 2|ee` "`
* @param currentPage WVQHb3Pe0
* The currentPage to set. z<t2yh(DF
*/ %6fnL~A
publicvoid setCurrentPage(int currentPage){ !8|r$mN8
this.currentPage = currentPage; :f Rta[
} !2AD/dtt
DHn\ =M
/** ?XVE{N
* @return 1H">Rb30@
* Returns the everyPage. V+sZ;$
*/ ]2"UR_x
publicint getEveryPage(){ 4Kj8i
return everyPage; ]+pE1-p\
} =4x6v<
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/** z I9jxwXU
* @param everyPage )ty>{t
* The everyPage to set. s3ASA.*
*/ 8}[<3K%*g
publicvoid setEveryPage(int everyPage){ ~g[D!HV|yu
this.everyPage = everyPage; 0*P-/)o x
} a>#$&&oQ0
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/** 3k6Dbz
* @return '9vsv\A&
* Returns the hasNextPage. E}w5.1
*/ L1`^M
publicboolean getHasNextPage(){ -2laM9Ed
return hasNextPage; ffB<qf)?G
} h3>u[cX%
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/** R^@`]dX$
* @param hasNextPage _,F\%}
* The hasNextPage to set. +c]D2@ctG
*/ XOS^&;
publicvoid setHasNextPage(boolean hasNextPage){ K vPLA{
this.hasNextPage = hasNextPage; k%-y\WM
} -{?xl*D
y4n~gTo(?
/** !eb{#9S*
* @return ~
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* Returns the hasPrePage. XkW@"pf&Fh
*/ o}wRgG
publicboolean getHasPrePage(){ [=-,i#4
return hasPrePage; +=L+35M
} |tY6+T}
tg%<@U`7=
/** lzFg(Ds!f
* @param hasPrePage HF&dHD2f
* The hasPrePage to set. G'HLnx}Yi
*/ `"~ X1;
publicvoid setHasPrePage(boolean hasPrePage){ i7\>uni
this.hasPrePage = hasPrePage; h4slQq~K
} ,pZz`B#
P4MP`A
/** =AHV{V~
* @return Returns the totalPage. f4X}F|!h
* oqK:
5|
*/ |CS&H2!s
publicint getTotalPage(){ u0uz~ s
return totalPage; q{yzux
} u7p:6W
[ifQLsHA
/** phwq#AxQ
* @param totalPage LXe'{W+bk
* The totalPage to set. 4uVyf^f\]f
*/ hB:+_[=Kj.
publicvoid setTotalPage(int totalPage){ F zBny[F
this.totalPage = totalPage; [h\_yU[P
} {5fq4AA6
;ov}%t>UD
} a}Jy o!.
3
}rx(
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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 ."q8 YaW
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个PageUtil,负责对Page对象进行构造: .B$3y#TOb
java代码: 6>EoU-YX}l
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/*Created on 2005-4-14*/ 5_L43-
package org.flyware.util.page; XoiZ"zE
~-(X\:z}
import org.apache.commons.logging.Log; #|e5i9l*B
import org.apache.commons.logging.LogFactory; _..5G7%#%
JDMsco+j5
/** IZ_ B $mo
* @author Joa Y9(BxDP_+Y
* VqB9^qJ]!
*/ IG@@CH
publicclass PageUtil { SR\$ fmo
a@gm r%C
privatestaticfinal Log logger = LogFactory.getLog L\kT9wWK|
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(PageUtil.class); CwfGp[|}e
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/** RQ51xTOL4]
* Use the origin page to create a new page x\(yjNZH
* @param page %gx>|
* @param totalRecords q/YO5>s15
* @return f]^ @z<FC
*/ hB*3Py27L
publicstatic Page createPage(Page page, int S4X['0rX!
P,Rqv)}X
totalRecords){ $U5$*R@jo[
return createPage(page.getEveryPage(), 0EP8MR SR
v]KI=!Gs
page.getCurrentPage(), totalRecords);
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} }A_>J7w
C}mWX7<Z.
/** _:;j)J0
* the basic page utils not including exception evGUSol?:n
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handler iJK rNRj
* @param everyPage \~q cYp
* @param currentPage s((_^yf
* @param totalRecords wZUR
* @return page ()i!Uo
*/ &($Zs'X
publicstatic Page createPage(int everyPage, int Z})n%l8J]p
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currentPage, int totalRecords){ 6P I-"He
everyPage = getEveryPage(everyPage); Th//u I+
currentPage = getCurrentPage(currentPage); s97L/iH
int beginIndex = getBeginIndex(everyPage, RJI*ZNbA
N[,/VCW
currentPage); 7QkAr
int totalPage = getTotalPage(everyPage, MtO p][i
<ByDT$E_
totalRecords); 0#KB.2AP
boolean hasNextPage = hasNextPage(currentPage, *:A)j?(
~d?\rj3=
totalPage); }"?KHy
boolean hasPrePage = hasPrePage(currentPage); >(HUW^T/9z
CSooJ1Ep~'
returnnew Page(hasPrePage, hasNextPage, R OQIw
everyPage, totalPage, f?C !Br}
currentPage, s2ys>2k
YB} _zuZ4&
beginIndex); 62LQUl]<
} \
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privatestaticint getEveryPage(int everyPage){ 7e"(]NC84
return everyPage == 0 ? 10 : everyPage; Kn9,N@bU_
} DEC,oX!bI1
-Q8pWtt
privatestaticint getCurrentPage(int currentPage){ T't^pO-`
return currentPage == 0 ? 1 : currentPage; l9.wMs*`X
} Q$9`QY*6"p
*WgP+"h
privatestaticint getBeginIndex(int everyPage, int KXFa<^\o
K~WwV8c9;
currentPage){ n%<.,(.(S
return(currentPage - 1) * everyPage; qQ6NxhQo
} ;SVF"Uo
\ca4X{x
privatestaticint getTotalPage(int everyPage, int [P{Xg:0
`czXjZE
totalRecords){ q+o(`N'~G
int totalPage = 0; WiviH#hF
+o/;bm*U<K
if(totalRecords % everyPage == 0) MOmp{@
totalPage = totalRecords / everyPage; <STjB,_s
else Rb~Kyy$
totalPage = totalRecords / everyPage + 1 ; ^J~}KOH
knBT(x'+
return totalPage; <$njU=YE&
} t@v>eb
}RUC#aW1
privatestaticboolean hasPrePage(int currentPage){ nhCB])u8l
return currentPage == 1 ? false : true; D1O7S]j
} d*>M<6b-
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privatestaticboolean hasNextPage(int currentPage, ?\#4`9
h=4{.EegG&
int totalPage){ O.K8$
return currentPage == totalPage || totalPage == "3j0)
`g :<$3}
0 ? false : true; IB*%PMTF
} !Xj m h$F
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} 3iEcLhe"4
4
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MB |(,{S
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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。 !6 $>|
"?9fL#8f*!
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 ;Ok11wOw
Vd1K{rH#
做法如下: D@JHi'F
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 Om1z
Xs`:XATb/
的信息,和一个结果集List: 8m*\"_S{
java代码: &'](T9kg=
g*tLqV
F#<PFT4i
/*Created on 2005-6-13*/ 9H)uTyuNi
package com.adt.bo; r?+u}uH
Uq+
_#{2(
import java.util.List; R$3JbR.
/pge 7P
import org.flyware.util.page.Page; e-K 8K+7
f%}+.eD
/** {Jy%h8n*
* @author Joa .BUl$RW|
*/ nRE}F5k
publicclass Result { Q.]
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[qI* ]
private Page page; Z{CL!
y-X'eCUz
private List content; $tKATL*
w0I
/
/** %7@H7^s}9
* The default constructor J-f0
*/ dB,#`tc=,
public Result(){ [uY2 Nh
super(); (hV"z; rI
} ,6bMfz
@/u`7FO$&
/** A X#!9-m3
* The constructor using fields ,Ex\\p-
* 2&d&$Jg
* @param page %Uk/P
* @param content Jqj6L993e
*/ *u>\&`h=
public Result(Page page, List content){ k$ M4NF~$
this.page = page; :&-}S>pC
this.content = content; &}$D[ 4N
} IjRmpVcwN
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/** K{P#[X*5
* @return Returns the content. }\{1`$*~
*/ 79x9<,a)
publicList getContent(){ D5:{fWVsV/
return content; 6e_dJ=_
} kI:}| _
V^\8BVw
/** A?`jnRo=\
* @return Returns the page. 40|,*wi
*/ +3&zN(
public Page getPage(){ .N*Pl(<[
return page; h;-yU.(w
} dlG=Vq&Y
kdn'6>\
/** 6<$Odd
* @param content E@P %v{)
* The content to set. ;q:jl~
*/ y|Ir._bt
public void setContent(List content){ me'd6!O9-
this.content = content; k<cgO[m
} 6<' 21
^k
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/** wN2QK6Oc
* @param page VwEb7v,^0\
* The page to set. XEdzpkB
*/ ixV0|P8,c
publicvoid setPage(Page page){ @fa@s-wb
this.page = page; 8Th` ]tI
} #Jna6
} [xT:]Pw}
BbRBT@
=b[_@zq]
r%e KFS
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L|
2. 编写业务逻辑接口,并实现它(UserManager, EaWS. eK
Nx-uQ^e*1
UserManagerImpl) fPR$kch
java代码: %eJGte-
Vp<seO;7o
_ z;q9&J)
/*Created on 2005-7-15*/ fd#jY}
package com.adt.service; ?]rPRV
_$p$")
import net.sf.hibernate.HibernateException; gN>2xnh'm
$-c!W!H
import org.flyware.util.page.Page; t!2(7=P30(
<HRBMSR+
import com.adt.bo.Result; >OP+^^oZ<
o=RM-tR`v
/** 7y`}PMn
* @author Joa 5P .qXA"D
*/ dVQ-k
publicinterface UserManager { ~h"/Tce
XUF\r]B,9
public Result listUser(Page page)throws 2jbIW*
.>(Q)"v
HibernateException; fRfn2jA)d
Nk[2nyeO>
} Pub0IIs
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i%{3W:!4t
U#n#7G6fRp
java代码: jAh2N3)
OgcHS?
l_j4DQBRV
/*Created on 2005-7-15*/ X]loJoM9
package com.adt.service.impl; QW_agm
m>}8'N)
import java.util.List; +p8BGNW,
KI]wm
import net.sf.hibernate.HibernateException; GdVhK:<>
{u[V{XIUh
import org.flyware.util.page.Page; \*\R1_+
import org.flyware.util.page.PageUtil; h8G5GRD
?k[p<Uo
import com.adt.bo.Result; i-U4RZE
import com.adt.dao.UserDAO;
<}jPXEB"
import com.adt.exception.ObjectNotFoundException; `mH %!{P
import com.adt.service.UserManager; z5*=MlZ)R.
0GDvwy D1
/** $DBGLmw
* @author Joa dJ:MjQG`W
*/ # tdf>?
publicclass UserManagerImpl implements UserManager { hSGb-$~F
OquAql:
private UserDAO userDAO; L0%hnA@
jxgj,h"}9`
/** $3X-rjQtW
* @param userDAO The userDAO to set. ?8,%LIQ?
*/ %g]vxm5?
publicvoid setUserDAO(UserDAO userDAO){ h5kPn~
this.userDAO = userDAO; K~RoUE<3[
} $ XBAZ<"hd
i77GE
/* (non-Javadoc) S<nq8Ebmw
* @see com.adt.service.UserManager#listUser T88Y
qI
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(org.flyware.util.page.Page) 1x~U*vbhQ
*/ RQW6N??C
public Result listUser(Page page)throws kHc<* L_V
/q\_&@
HibernateException, ObjectNotFoundException { ~Z$bf>[(R7
int totalRecords = userDAO.getUserCount(); _kFYBd
if(totalRecords == 0) KyP)Qzp
throw new ObjectNotFoundException 9H]_4?aX
f]8I64
("userNotExist"); qIwV q!=
page = PageUtil.createPage(page, totalRecords);
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List users = userDAO.getUserByPage(page); $mA5@O~C5\
returnnew Result(page, users); bVr*h2p
} lz |
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} H/~?@CE(YC
7yI@"c#O
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PWgDFL?
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 {Z{o"56f
K_-d(
询,接下来编写UserDAO的代码: gd@p|PsS^
3. UserDAO 和 UserDAOImpl: [IM%b~j(^
java代码: GgFi9Ffj
!$XHQLqF2
0>6DSQq~t(
/*Created on 2005-7-15*/ f%qt)Ick
package com.adt.dao; @=]8^?$t
0
10sK]XI
import java.util.List; \6j^kY=
u>T76,8|\
import org.flyware.util.page.Page; #$'"cfRxc
GtI6[ :1t
import net.sf.hibernate.HibernateException; t]_S
h=RDO
/** v$|mo;6
* @author Joa rE!1wc>L
*/ msTB'0
publicinterface UserDAO extends BaseDAO { 2C+(":=}
^Ip3A
publicList getUserByName(String name)throws 3-wD^4)O,
q@#BPu"\l
HibernateException; +S {
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publicint getUserCount()throws HibernateException; =LH}YUmd
ddpl Pzm#
publicList getUserByPage(Page page)throws )GB`*M[
+QqH}=
M
HibernateException; !r&Bn6*
,I*X)(
} M StX*Zw
)BV=|,j
<4?*$
9k2,3It
whkJ pK(
java代码: Z(!pYhLq
8cr NOZS6
4Z%Y"PL(K
/*Created on 2005-7-15*/ eO4)|tW
package com.adt.dao.impl; ]O{_O&w
Q)6va}2ai
import java.util.List; B%b_/F]e
6&!l'[hU
import org.flyware.util.page.Page; ,w\ wQn>]K
03E3cp"
import net.sf.hibernate.HibernateException; Kmry=`=A
import net.sf.hibernate.Query; C-#.RI7
W%8+t)
import com.adt.dao.UserDAO; [yd6gH
i!~>\r\6\
/** m6so]xr
* @author Joa KRk~w]
*/ Xem| o&
public class UserDAOImpl extends BaseDAOHibernateImpl zO2{.4
p?Sl}A@`
implements UserDAO { 0$Ff#8
wu^q`!ml
/* (non-Javadoc) @InJ_9E
* @see com.adt.dao.UserDAO#getUserByName m "]!I~jd
mU]s7` %<>
(java.lang.String) 6&],WGz
*/ xii$e
publicList getUserByName(String name)throws 3/tJDb5
V_M@g;<o
HibernateException { u%aFb*
String querySentence = "FROM user in class hT=f;6$
(w2(qT&