Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 \&kj#)JYA
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 gdTW
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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 8=L"rekV_
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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 P8X9bW~GQ
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分页支持类: OeASB}
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java代码: K\%\p$ZD
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package com.javaeye.common.util; .tG3g:
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import java.util.List; @H#Fzoo.
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publicclass PaginationSupport { DVhBZ!u9
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publicfinalstaticint PAGESIZE = 30; KZ[TW,Gw
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privateint pageSize = PAGESIZE; V;SV0~&
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privateList items; fn
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privateint totalCount; ck0%H#BYY
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privateint[] indexes = newint[0]; ;303fS
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privateint startIndex = 0; s(fkb7W,gO
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public PaginationSupport(List items, int )C?H m^#
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totalCount){ Q3hf =&$
setPageSize(PAGESIZE); ;
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setTotalCount(totalCount); Ln&~t(7
setItems(items); k%~;mu"4}
setStartIndex(0); }G{"Mp4
} In?+
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public PaginationSupport(List items, int &AxtSIpucP
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totalCount, int startIndex){ (kO (R#M
setPageSize(PAGESIZE); x f{`uHa8
setTotalCount(totalCount);
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setItems(items); JL#LCU
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setStartIndex(startIndex); ,\
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} OT$Ne
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public PaginationSupport(List items, int V Zbn@1
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totalCount, int pageSize, int startIndex){ 4"eFR'g
setPageSize(pageSize); Jf=V<
setTotalCount(totalCount); $}b)EMMM
setItems(items); YBj*c$.D0
setStartIndex(startIndex); {06-h %qr
} "9[2vdSX
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publicList getItems(){ Q{S{|.w-
return items; 2jhJXM=~
} b4^O=
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publicvoid setItems(List items){ Ms5qQ<0v_
this.items = items; S)ipkuj X
} w6>P[oW
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publicint getPageSize(){ gp$]0~[tO
return pageSize; rd%uc~/
} Pw]+6
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publicvoid setPageSize(int pageSize){ 2K/t[.8
this.pageSize = pageSize; $'>iNMtK{p
} .?APDr"QQH
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publicint getTotalCount(){ ))dqC l
return totalCount; '$p`3Oqi
} pLF,rOb
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publicvoid setTotalCount(int totalCount){ _\IA[-C+O
if(totalCount > 0){ sd+_NtH
this.totalCount = totalCount; %e25Z.Se$
int count = totalCount / E83$(6z
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pageSize; T}?b,hNl$
if(totalCount % pageSize > 0) 8*?H~q~
count++; sF :pwI5^
indexes = newint[count]; g2?W@/pa
for(int i = 0; i < count; i++){ k
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indexes = pageSize * I_Lm[
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} ktfxb<%
}else{ J3 oUtu
this.totalCount = 0; n4{?Odrf
}
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} CTg79
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publicint[] getIndexes(){ \rh+\9(
return indexes; tkptm%I_
} C[TjcHoA
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publicvoid setIndexes(int[] indexes){ 80%"2kG
this.indexes = indexes; Cz5U
} KRd'!bG=1
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publicint getStartIndex(){ hEo$Jz`
return startIndex; ]==7P;_-
} p; , V
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publicvoid setStartIndex(int startIndex){ 6IK>v*<
if(totalCount <= 0) 5IzCQqOPgX
this.startIndex = 0; T,/<'cl"
elseif(startIndex >= totalCount) tr0kTW$Ad
this.startIndex = indexes %kkDitmI{
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[indexes.length - 1]; U. <c#S
elseif(startIndex < 0) Hxac#(,7
this.startIndex = 0; Y@UW\d*'%I
else{ &09~ D8f'
this.startIndex = indexes d7g$9&/q
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[startIndex / pageSize]; qD"~5vtLqQ
} vP'!&}
} NODg_J~T
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publicint getNextIndex(){ OiC|~8
int nextIndex = getStartIndex() + peS4<MqWu
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pageSize; Ai 8+U)
if(nextIndex >= totalCount) _a$5"
return getStartIndex(); 07(LLhk@d
else {9P(U\]e]k
return nextIndex; wD6QN
} uJ1oo| sn
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publicint getPreviousIndex(){ 1:DA{ejS
int previousIndex = getStartIndex() - 4Rp[>}L
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pageSize; sy(bL_%
if(previousIndex < 0) `\ nKPj
return0; :SMf
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else 1z,P"?Q
return previousIndex; Um-Xb'R*]V
} x>K,{{B)X
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} cF9ZnT.
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抽象业务类 5Em.sz;:8
java代码: \G/ZA) t
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/** :c}PW"0v
* Created on 2005-7-12 h6`VU`pPI
*/ wB[
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package com.javaeye.common.business; mH<|.7~0
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import java.io.Serializable; :$X dR:f}}
import java.util.List; K`|V1L.m
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import org.hibernate.Criteria; nhm#_3!6A
import org.hibernate.HibernateException; XTb.cqOC
import org.hibernate.Session; >)>~S_u
import org.hibernate.criterion.DetachedCriteria; ,&O&h2=
import org.hibernate.criterion.Projections; 51AA,"2[_
import //$^~}wt
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org.springframework.orm.hibernate3.HibernateCallback; G%jV}7h
import X2np.9hie
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org.springframework.orm.hibernate3.support.HibernateDaoS VqOTrB1w/
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upport; "x:-#2+h
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import com.javaeye.common.util.PaginationSupport; :Xx7':5
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public abstract class AbstractManager extends #H8QX5b)
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HibernateDaoSupport { JV2[jo}0N
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privateboolean cacheQueries = false; s9u7zqCF
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privateString queryCacheRegion; }g 2l
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publicvoid setCacheQueries(boolean *li5/=UC5*
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cacheQueries){
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this.cacheQueries = cacheQueries; oO;<$wx2t
} p Bu}c<
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publicvoid setQueryCacheRegion(String s2+_`Ogg
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queryCacheRegion){ jfa<32`0E
this.queryCacheRegion = 94rx4"AN8;
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queryCacheRegion; BSEP*#s
} Bq,Pk5b
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publicvoid save(finalObject entity){ ZGd7e.u=
getHibernateTemplate().save(entity); #g
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} rO,n~|YJ
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publicvoid persist(finalObject entity){ X5Y. o&
getHibernateTemplate().save(entity); b%j4W)Z
} uy=<n5`oNG
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publicvoid update(finalObject entity){ PB{5C*Y7^k
getHibernateTemplate().update(entity); w- wJhc|
} K}LF ${bS
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publicvoid delete(finalObject entity){ |'L$ogt6
getHibernateTemplate().delete(entity); t..@69
} HhTD/
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publicObject load(finalClass entity, B@vup {Kg
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finalSerializable id){ 'sjks sy.3
return getHibernateTemplate().load {\k:?w4
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(entity, id); r?Pk}Q
} $! UEpQ
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publicObject get(finalClass entity, <+`}:
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finalSerializable id){ 6"bdbV=t
return getHibernateTemplate().get Hg[AulNna
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(entity, id); W TC/mcS
} *&F~<HC2+
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publicList findAll(finalClass entity){ I9cZZ`vs
return getHibernateTemplate().find("from ~0{F,R.$
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" + entity.getName()); G4f%=Z
} `]l[p+DO
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publicList findByNamedQuery(finalString cvnRd.&
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namedQuery){ /gLi(Uw
return getHibernateTemplate s|Zv>Qt
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().findByNamedQuery(namedQuery); >!P !F(
} "Ze<dB#,Y
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publicList findByNamedQuery(finalString query, F[oTc^dr
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finalObject parameter){ ]1KF3$n0
return getHibernateTemplate 4--[.j*W
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().findByNamedQuery(query, parameter); H|B4.z
} :YN,cI d*
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publicList findByNamedQuery(finalString query, 6\/(TW&
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finalObject[] parameters){ 2-u9%
return getHibernateTemplate f(*^zga,
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().findByNamedQuery(query, parameters); E`UEl$($
} ;jT@eBJ
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publicList find(finalString query){ B#x.4~YX
return getHibernateTemplate().find ;kF+V*
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(query); Hz3KoO &
} *8xMe
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publicList find(finalString query, finalObject %>k$'UWzK
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parameter){ ;PX>] r5U0
return getHibernateTemplate().find lhx]r}@'MC
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(query, parameter); gLPgh%B4
} s4{ >7`N2
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public PaginationSupport findPageByCriteria [5Pin>]z
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(final DetachedCriteria detachedCriteria){ Z\*jt B:
return findPageByCriteria c{K[bppJ*
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); %C(^v)"
} [cf!%3>53
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public PaginationSupport findPageByCriteria #x5?RHX56
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(final DetachedCriteria detachedCriteria, finalint "\M^jO
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startIndex){ p v*n.U6
return findPageByCriteria $/;;}|hqi
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(detachedCriteria, PaginationSupport.PAGESIZE, d,caO E8N
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startIndex); WkR=(dss8
} 924a1
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public PaginationSupport findPageByCriteria E?[]N[0Kl
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(final DetachedCriteria detachedCriteria, finalint @a}jnl(2
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pageSize, )wueR5P
finalint startIndex){ E(G&mfhb
return(PaginationSupport) ?mJ&zf|B8
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getHibernateTemplate().execute(new HibernateCallback(){ !qF t:{-h
publicObject doInHibernate $:SSm$k
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(Session session)throws HibernateException { JE.s?k
Criteria criteria = |(\T;~7'
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detachedCriteria.getExecutableCriteria(session); ?hS&OtW
int totalCount = c.eA]m q
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((Integer) criteria.setProjection(Projections.rowCount %?z8*G]M
Ea\Khf]2
()).uniqueResult()).intValue(); j$Z:S~*
criteria.setProjection `5CuH
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(null); Pmj%QhOYE
List items = +1=]93gP
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criteria.setFirstResult(startIndex).setMaxResults Y]6kA5
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.
(pageSize).list(); FA3YiX(-e
PaginationSupport ps = !omf>CW;ud
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new PaginationSupport(items, totalCount, pageSize, H$={i$*,Y
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startIndex); 7S]<?>*
return ps; 1'"TO5
} _[t:Vme}v
}, true); 5isqBu
} ?,0 a#lG
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public List findAllByCriteria(final cHjnuL0fsy
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DetachedCriteria detachedCriteria){ DA wUG
return(List) getHibernateTemplate $Cx ?%X^b
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().execute(new HibernateCallback(){ Js}1_K
publicObject doInHibernate ni`uO<\U
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(Session session)throws HibernateException { R7ze~[oF
Criteria criteria = J_rb3
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detachedCriteria.getExecutableCriteria(session); g?i0WS
return criteria.list(); @K=C`N_22
} GZWU=TC2{2
}, true); GW;O35
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} :ExCGS[
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public int getCountByCriteria(final Sahz*f
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DetachedCriteria detachedCriteria){ r:-,qy
Integer count = (Integer) iininITOS{
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getHibernateTemplate().execute(new HibernateCallback(){ Vc*"Q8aZ~
publicObject doInHibernate -fCR^`UOS
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(Session session)throws HibernateException { )
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Criteria criteria = g`\5!R1
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detachedCriteria.getExecutableCriteria(session); S}/5W
return !M@jW[s
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criteria.setProjection(Projections.rowCount _`.Wib+
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()).uniqueResult(); @
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} &5d~ODO
}, true); ;(r,;S_`0
return count.intValue(); 6%L#FSI
} !j%MN{#a
} 51-@4E2:l:
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用户在web层构造查询条件detachedCriteria,和可选的 9zE/SDu7\
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 $q*hE&x
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PaginationSupport的实例ps。 e82xBLxR%
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ps.getItems()得到已分页好的结果集 A"i$.dR{
ps.getIndexes()得到分页索引的数组 ZgA+$}U)uW
ps.getTotalCount()得到总结果数 .oH)eD
ps.getStartIndex()当前分页索引 i[/`9 AK
ps.getNextIndex()下一页索引 z07Xj%zX9
ps.getPreviousIndex()上一页索引 i62GZeE
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 1+9!W
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,尤其是上面的示例代码,让我着实觉得该对我原来的分页查询做 =z!/:M
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一下代码重构了。 9m%2&fjK^
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我把原本我的做法也提供出来供大家讨论吧: MSE0z!t
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首先,为了实现分页查询,我封装了一个Page类: G@P+M1c
java代码: X`28?
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/*Created on 2005-4-14*/ y({lE3P
package org.flyware.util.page; 08+\fT [
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/** A|YiSwyy
* @author Joa o .*t
* %7[q%S
*/ dU-nE5
publicclass Page { Irui{%T
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/** imply if the page has previous page */ qOv`&%txW
privateboolean hasPrePage; Tvt(nWn(H1
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/** imply if the page has next page */ &"(zK"O
privateboolean hasNextPage; T:SqENV
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f{
/** the number of every page */ , Xxp]*K2
privateint everyPage; .}Eckqkp
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/** the total page number */ NOmFQ)/ &
privateint totalPage; nNf*Q
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/** the number of current page */ aNBwb9X
privateint currentPage; B=~uJUr
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/** the begin index of the records by the current md `=2l
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query */ >qBJK)LHOv
privateint beginIndex; -]t>'Q?
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/** The default constructor */ ]FgKL0
public Page(){ iBwM]Eyv.
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} Xzl$Qc
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/** construct the page by everyPage {eVv%sbq
* @param everyPage `O5427Im
* */ -@ra~li,yQ
public Page(int everyPage){ ^7a@?|,q8
this.everyPage = everyPage; k136n#KN1
} qeb} ~FL"o
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/** The whole constructor */ xIwILY|W=
public Page(boolean hasPrePage, boolean hasNextPage, O`5h jq#
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int everyPage, int totalPage, vqZBDQ0
int currentPage, int beginIndex){ t)= dKC
this.hasPrePage = hasPrePage; q0DRT4K
this.hasNextPage = hasNextPage; [RY Rt/?Q
this.everyPage = everyPage; J=&}$
this.totalPage = totalPage; P| hwLM
this.currentPage = currentPage; *s<cgPKJ@
this.beginIndex = beginIndex; G1\F7A
} vCXmu_S4^>
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/** j^WYMr,
* @return Z;,G:@,
* Returns the beginIndex. M|Nh(kvH
*/ 9kB R /{
publicint getBeginIndex(){ A!Tm[oqu
return beginIndex; 2j#Dwa(lZQ
} UB+7]S
@AM11v\:
/** e)N<r
* @param beginIndex +z:>Nl
* The beginIndex to set. G4rzx%W?
*/ Ud7Z7?Ym
publicvoid setBeginIndex(int beginIndex){ PT
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this.beginIndex = beginIndex; ]s!id[j
} 94^b"hU
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/** "0,FB4L[U5
* @return '1(6@5tyWk
* Returns the currentPage. mHV{9J
*/ Ql%B=vgKL
publicint getCurrentPage(){ UNK.39
return currentPage; jgS3#
} ANJL8t-m
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/** }+Q4s]
* @param currentPage 3=^)=yOd
* The currentPage to set. C"$~w3A k
*/ ;mRZ_^V;
publicvoid setCurrentPage(int currentPage){ oe|8
this.currentPage = currentPage; b(CO7/e>
} ~y?Nn8+&f
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/** \XYidj
* @return )2#&l
* Returns the everyPage. 2r;h">
*/ ca3SE^
publicint getEveryPage(){ _aBy>=2c$
return everyPage; `SOQPAnK+;
} RRpY%-8M
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/** hlZ{bO'f
* @param everyPage SM%/pu;
* The everyPage to set. D.Cn`O}
*/ 3l,-n|x
publicvoid setEveryPage(int everyPage){ *8uS,s6g
this.everyPage = everyPage; tv`b##
} l($8HAJ
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/** p2k`)=iX
* @return jvAjnh#
* Returns the hasNextPage. ;]b4O4C\
*/ DA04llX~
publicboolean getHasNextPage(){ 5!cp^[rGL
return hasNextPage; -FI)o`AE
} lC`w}0p
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/** B- $?5Ft!
* @param hasNextPage vm{8x o
* The hasNextPage to set. +2}cR66%
*/ 8aIqc
publicvoid setHasNextPage(boolean hasNextPage){ %P M#gnt@
this.hasNextPage = hasNextPage; /}J_2
} Qe\vx1GRLH
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/** KO~KaN
* @return v|\#wrCT?
* Returns the hasPrePage. |cP:1CRzi
*/ TnKv)%VF
publicboolean getHasPrePage(){ ?QzL#iO}h
return hasPrePage; L6DYunh}^N
} rfYa<M Qc
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/** +3o0GJ
* @param hasPrePage sW'_K.z
* The hasPrePage to set. EI7n|X
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*/ [3s-S+n
@
publicvoid setHasPrePage(boolean hasPrePage){ p5tb=Zg_
this.hasPrePage = hasPrePage; (QL:7
} ('Qq"cn#
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/** |m6rF7Q
* @return Returns the totalPage. ]s\vc:cc?
* 0nL
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*/ Yj*T'<e
publicint getTotalPage(){ 71Za!3+
return totalPage; pgiZA?r*<
} *4NY"EwjN
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/** n|6G\99l+M
* @param totalPage Du65>O
* The totalPage to set. 8Iu6r}k?~`
*/ qg=`=]j
publicvoid setTotalPage(int totalPage){ {?Y\T
this.totalPage = totalPage; r5ldK?=k+*
} r~YBj>}
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} ZOcpF1y
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YY :{/0?
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上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 iE
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个PageUtil,负责对Page对象进行构造: S{N4[U?V>
java代码: }/&Zo=Q$
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/*Created on 2005-4-14*/ cu
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package org.flyware.util.page; y<j7iN
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import org.apache.commons.logging.Log; m$^5{qpg
import org.apache.commons.logging.LogFactory; y0(.6HI
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/** 0C>_aj
* @author Joa Yl>Y.SO
* ;tVd+[8
*/ r7g@(K
publicclass PageUtil { :Ae#+([V
`^[Tu 1
privatestaticfinal Log logger = LogFactory.getLog {<@ud0A:\
.\T!oSb4[
(PageUtil.class); W_E^+Wl@
v]EZYEXFL)
/** $Wj{B@k
* Use the origin page to create a new page _AX,}9
* @param page 3N-
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* @param totalRecords
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* @return 8y<.yfgG
*/ 2t_g\Q
publicstatic Page createPage(Page page, int "{qnm+G
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totalRecords){ \%Y`>x.
return createPage(page.getEveryPage(), NQ;X|$!zH
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page.getCurrentPage(), totalRecords); p7-\a1P3
} FXDB> }8
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/** K$,<<hl
* the basic page utils not including exception s|A[HQUtJ
e+-#/i*
handler 6q8}8;STTY
* @param everyPage IB|6\uKn
* @param currentPage DJ<+" .v!
* @param totalRecords ut\X{.r7
* @return page B !,&{[D
*/ Nv.
publicstatic Page createPage(int everyPage, int (wq8[1Wzup
#<"od '{U
currentPage, int totalRecords){ n
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everyPage = getEveryPage(everyPage); 035jU '
currentPage = getCurrentPage(currentPage); keRLai7h
int beginIndex = getBeginIndex(everyPage, Y)F(-H)
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currentPage); yc?L
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int totalPage = getTotalPage(everyPage, xtD(tiqh.;
T=u"y;&L
totalRecords); p *42
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boolean hasNextPage = hasNextPage(currentPage, ,(Zxd4?y
; 8DtnnE
totalPage); BRM `/s
boolean hasPrePage = hasPrePage(currentPage); {g1"{
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returnnew Page(hasPrePage, hasNextPage, ,M?8s2?
everyPage, totalPage, 8)?&eE'
currentPage, hvO$ f.i
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beginIndex); IMbF]6%p(
} 5o 5DG
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privatestaticint getEveryPage(int everyPage){ \3^V-/SJf
return everyPage == 0 ? 10 : everyPage; ],0I`!\
} dR.?Kv(,E
LKc p.i
privatestaticint getCurrentPage(int currentPage){ =,;$d*h
return currentPage == 0 ? 1 : currentPage; frPQi{u$
} Z3c\}HLY
_[z)%`kay
privatestaticint getBeginIndex(int everyPage, int .rO~a.kG
2bTS,N/>
currentPage){ $`W3`}#fM
return(currentPage - 1) * everyPage; O&aD]~|
}
rn(
drG
qGH[kd
privatestaticint getTotalPage(int everyPage, int 9y&;6V.'
Xw'sh#i2
totalRecords){ $8U$.~v
int totalPage = 0; m-\_L=QzM
4(P<'FK $
if(totalRecords % everyPage == 0) F*#!hWtb
totalPage = totalRecords / everyPage; CSoVB[vS
else KzV|::S^
totalPage = totalRecords / everyPage + 1 ; rQ _cH
z(Uz<*h8
return totalPage; iOEBjj;C
} =dHdq D
a@jM%VZ
privatestaticboolean hasPrePage(int currentPage){ +JC"@
return currentPage == 1 ? false : true; '@+q_v@Jl
} Ew{*)r)m
d9S?dx
privatestaticboolean hasNextPage(int currentPage, w=(dJ(7gu
BNjMq
int totalPage){ H.XyNtJ
return currentPage == totalPage || totalPage == <)a$5"AP
OqMdm~4B!j
0 ? false : true; Uaux0W
} ]U'zy+
QeFt
WjlqC
(n.IK/:
} iOhX\@&
ga\s5
\F`>zY2$%
FIfLDT+ Wh
~E8/m_> rU
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。 3]9wfT%d
,7s+-sRG
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 ZG1TRF "
^pu8\K;~
做法如下: w<THPFFF"
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 Wd!Z`,R
$PRd'YdL/
的信息,和一个结果集List: k=kkF"
java代码: =s*c(>
G7`mK}J7
W0mvwYON[
/*Created on 2005-6-13*/ h(AL\9{=}
package com.adt.bo; YU6|/
<8
`u_MdB}<x;
import java.util.List; &F#eYEuy
&E0^Jz
import org.flyware.util.page.Page; +RM!j9Rq
Lz_.m
/** BjPU@rS.U
* @author Joa g}Lm;gs!>
*/ r
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publicclass Result { N-2_kjb!
Bf y
private Page page; A#?Cts,M
0Cf'\2
private List content; S2|pn\0V
V\L%*6O
/** 73S
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* The default constructor E>-I
|X"L1
*/ zBq&/?
public Result(){ A7#nBHwxZ
super(); Y=Ic<WHR
} vJi<PQ6
A =Z$H2
/** ?8s$RYp14
* The constructor using fields 5`e;l$
M`
* ](n)bF+ym
* @param page y"7*u
3>"
* @param content p`\>GWuT!
*/ tj*0Y-F~
public Result(Page page, List content){ o[eZ"}~
this.page = page; 95j`^M)Q
this.content = content; Tr}XG
} V>obMr^5
u' kG(<0Y
/** EQpF:@_
* @return Returns the content. AFBWiuwI3
*/ ~&<vAgy,
publicList getContent(){ Crj7n/mp]s
return content; ]gnEo.R
} = vF!
0Ba]Zo Z
/** h$9ut@I
* @return Returns the page. .]4MtG
*/ 60ciI,_`
public Page getPage(){ A\9LJ#E
return page; 0uM&F[.x@g
} RS&BS;
4,R"(ej
/** *CQZ6&^
* @param content Ja&S_'P[
* The content to set. &M3KJ I0L
*/ yDZm)|<.
public void setContent(List content){ sz/^Ie-~
this.content = content; W?wt$'
} (`#z@,1
r: >RH,
/** mqsAYzG
* @param page K8[Um!(
* The page to set. ,H.5TQ#
*/ h0dZr-c
publicvoid setPage(Page page){ (dyY@={q
this.page = page;
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} OXKV6r6f
} %;u"2L0@
W{Z7=
W?kJ+1"(
1k)pJzsc
+C,/BuG
2. 编写业务逻辑接口,并实现它(UserManager, R:Ih#2R
F1-C8V2H
UserManagerImpl) {SXSQ '=
java代码: ^\`a-l^
,G="wI
[MbbL
/*Created on 2005-7-15*/ Tjv'S
<
package com.adt.service; aqQ+A:g
q7soV(P
import net.sf.hibernate.HibernateException; KkpbZ7\@
>O
rIY
import org.flyware.util.page.Page; zv;xxAX
[N9yWuc
import com.adt.bo.Result; 1$C?+H
zv/dj04>
/** ?fC9)s
* @author Joa d8 Jf3Mo
*/ (.Ak*
publicinterface UserManager { CDuA2e
L$);50E
public Result listUser(Page page)throws xz.M'az\
1+7_L`SB
HibernateException; id8QagJ
=)g}$r
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} @b., pwZF
4]p#9`j
bnanTH9-
uHmvHA~/c8
&!WRa@x0I
java代码: -K8F$\W
!||Gfia
|sFd5X
/*Created on 2005-7-15*/ @+p(%
package com.adt.service.impl; {dRZ2U3
6`7bk35B
import java.util.List; mPQT%%MF
wWf_d jd
import net.sf.hibernate.HibernateException; j[w=pF,o
HRM-r~2:-]
import org.flyware.util.page.Page; -gt?5H h
import org.flyware.util.page.PageUtil; ewdTsgt'
m0h,!
import com.adt.bo.Result; 52#6uBe
import com.adt.dao.UserDAO; }
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import com.adt.exception.ObjectNotFoundException; LA2/<:
import com.adt.service.UserManager; 1t^9.!$@y
4J(-~
/** Q/4ICgo4
* @author Joa ,!%E\`
*/ LdNpb;*
publicclass UserManagerImpl implements UserManager { s7:H
\SO)|M>. a
private UserDAO userDAO; Lr8|S
ZS]Z0iZv9
/** a:HN#P)12
* @param userDAO The userDAO to set. ?)k]Vg.
*/ \.H9e/vU`
publicvoid setUserDAO(UserDAO userDAO){ |V{ Q
this.userDAO = userDAO; aL90:,V
} M,li\)J!&
&s?uMWR
/* (non-Javadoc) 5}]+|d;
* @see com.adt.service.UserManager#listUser 4~FRE)8
$>yfu=]?
(org.flyware.util.page.Page) @b^$h:H
*/ 4L{]!dox
public Result listUser(Page page)throws > 3(,s^
x@bqPZ t
HibernateException, ObjectNotFoundException { oZ tCx
int totalRecords = userDAO.getUserCount(); ceCO *m~
if(totalRecords == 0) E7@Gpu,o
throw new ObjectNotFoundException ~UO}PI`C
);t+~YPS
("userNotExist"); i(cKg&+ktd
page = PageUtil.createPage(page, totalRecords); c@}t@k
List users = userDAO.getUserByPage(page); Tt{z_gU6
returnnew Result(page, users); </xf4.C
} |?g-8":H8P
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} D g0rVV6c
['pO=ho
0hGmOUO
MOCcp s*
a`f@&A`z
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 g%[:wjV;
7'i{JPm
询,接下来编写UserDAO的代码: z,SI
3. UserDAO 和 UserDAOImpl: 2;
,8 u
java代码: &}2@pu[S?7
X~"p]V_
c6c@XdV
/*Created on 2005-7-15*/ leH7II9
package com.adt.dao; R0tT4V+
~ |A0*
import java.util.List; e:'56?|
qT5"r488
import org.flyware.util.page.Page; \
ya@9OA
VWHpfm[r%
import net.sf.hibernate.HibernateException; Udn Rsp9S
q
jc4IW t~
/** Cfd* Q
* @author Joa ivq(eKy
*/ 'plUs<A
publicinterface UserDAO extends BaseDAO { vWeY[>oGur
:0 n+RL*5
publicList getUserByName(String name)throws |D/a}Av>B
$^{#hYq)o
HibernateException; Tjrb.+cua
L2EQ 9i'[
publicint getUserCount()throws HibernateException; C5TV}Bq\
@d 7V@F0d
publicList getUserByPage(Page page)throws c$&({Z{1
Fih
pp<
HibernateException; Ow4(1eE_
+M_ _\7
} <y^_&9
@/^mFqr2
zN]%p>,)HB
_[Imwu}
m=^]93+
java代码: $,, PF/N8c
kln)7SzPuk
Bh cp=#
/*Created on 2005-7-15*/ 5~IdWwG*w
package com.adt.dao.impl; m<>BxX
sr&W+4T
import java.util.List; @$%GszyQ'
y<Xu65
import org.flyware.util.page.Page; ;xzaW4(3
[
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import net.sf.hibernate.HibernateException; -mRgB"8
import net.sf.hibernate.Query; oU\7%gQ
;zD4#7=
import com.adt.dao.UserDAO; >Q=^X3to
Q#H"Se
/** R3|4|JlGR
* @author Joa \#dacQ2E@
*/ N\|z{vn
public class UserDAOImpl extends BaseDAOHibernateImpl ]T]{VB
*OFG3 uM
implements UserDAO { 1a{r1([)
B^P&+,\[}
/* (non-Javadoc) 3lpxh_
* @see com.adt.dao.UserDAO#getUserByName 0`c{9gY.
x@rQ7K>
(java.lang.String) W>d)(
*/ mi Q*enZi
publicList getUserByName(String name)throws HV/:OCK
AK&>3D
HibernateException { ~YCH5,
String querySentence = "FROM user in class ~KMah
EC,`t*<
com.adt.po.User WHERE user.name=:name"; F.$z7ee@
Query query = getSession().createQuery 1s=Q~*f~d
wT":
(querySentence); ~i%=1&K&`
query.setParameter("name", name); 9N9&y^SmD
return query.list(); #c@&mus
} #vV]nI<MF.
qovsM M
/* (non-Javadoc) <.4(#Ebd
* @see com.adt.dao.UserDAO#getUserCount() NC-K`)
*/ JXU?'@QY
publicint getUserCount()throws HibernateException { ,k4pW&A
int count = 0; 70 R6:
String querySentence = "SELECT count(*) FROM <L qJg
9!Mh(KtQ
user in class com.adt.po.User"; $]E+E.P
Query query = getSession().createQuery g[pU5%|"[
~KS@Ulrox
(querySentence); 9Tt%~m^
count = ((Integer)query.iterate().next pK3A/ry<
\~%+)a%%
()).intValue(); wX]$xZ!s
return count; (Fzy8
s
} 96V8R<
aH_c84DS
/* (non-Javadoc) :\"0jQ.y|
* @see com.adt.dao.UserDAO#getUserByPage G'/GDN^j
+M
I{B="7.
(org.flyware.util.page.Page) 4DCh+|r
*/ nahq O|~
publicList getUserByPage(Page page)throws AtCT
`3T=z{HR9g
HibernateException { *GE6zGdN
String querySentence = "FROM user in class }UW*[dCf>C
!s=$UC
com.adt.po.User"; gE\ ^ vaB
Query query = getSession().createQuery '1b 1N5~
C][hH?.
(querySentence); L4/ns@e
query.setFirstResult(page.getBeginIndex()) n~yKq"^
.setMaxResults(page.getEveryPage()); $"/l*H\h
return query.list(); @r*GGI!
} KUZi3\p9W>
wCLniCt
} )Ac,F6w
H;nzo3x
Zwc&4:5%
?; W"=I*3
o[!o+M
至此,一个完整的分页程序完成。前台的只需要调用 YTefEG]|q
# `E
userManager.listUser(page)即可得到一个Page对象和结果集对象 Cb{D[
m6e(Xk,)
的综合体,而传入的参数page对象则可以由前台传入,如果用 L!Y|`P#Yr
Ln,<|,fZN
webwork,甚至可以直接在配置文件中指定。 X^eyrqv
_r3Y$^!U
下面给出一个webwork调用示例: 2v ~8fr4
java代码: !FP ]
u?72]?SM
K _VIk'RB
/*Created on 2005-6-17*/ ^R@)CIQ
package com.adt.action.user; 5 [~HL_u;,
pE<a:2J
import java.util.List; .2@T|WD!Ah
49*f=gpGj2
import org.apache.commons.logging.Log; !ZUUn*e{5
import org.apache.commons.logging.LogFactory; |(%<FY$
import org.flyware.util.page.Page; t^":.}[Q
D|ze0A@
import com.adt.bo.Result; o!UB x<4
import com.adt.service.UserService; /(s |'"6
import com.opensymphony.xwork.Action; 2: gh q
-"nkC
/** IwnDG;+Ap
* @author Joa S,:!H@~B
*/ 0<`qz |_h
publicclass ListUser implementsAction{ G^d3$7
/P,1KVQPh
privatestaticfinal Log logger = LogFactory.getLog a8T9=KY^
cOP'ql{"
(ListUser.class); e#HPU
5CK\Z'c~!
private UserService userService; A_@..hX(
?Sh]kJO
private Page page; /W,hOv
0 j!<eN=
privateList users; =_k
8wkhbD|;
/* r[Pp[g-J
* (non-Javadoc) 30^q_|l:]
* 'Jf
LTG.
* @see com.opensymphony.xwork.Action#execute() >WLX5i&
*/ %W D^0U|
publicString execute()throwsException{ Gn
9oInY1
Result result = userService.listUser(page); p)B/(%
page = result.getPage(); J(#6Cld`c
users = result.getContent(); G;cC!x<
return SUCCESS; O"~[njwkE
} FA,n>
H1U$ApD
/** bQ3<>e\%B
* @return Returns the page. ^O7sQ7V"f=
*/ j$Ndq(<tG
public Page getPage(){
s*gqKQ;
return page; HQ"T>xb
} h!SsIy(
u
$-&Im<
/** bI0xI[#Q
* @return Returns the users. M4)U
[v
*/ Ox J0."
publicList getUsers(){ IWv5UmjN
return users; "W+>?u )
} `$jun
3mU~G}ig
/** hev;M)t
* @param page Zm*d)</>
* The page to set. CJN~p]\
*/ Nxt:U{`T'
publicvoid setPage(Page page){ _}p[(sTV
this.page = page; Y({
R\W|
} %(
7##f_
9oc_*V0<
/** | I:@:
* @param users !%65YTxY-
* The users to set. B\R X
*/ ShC$ue?Q
publicvoid setUsers(List users){ 1#3|PA#>
this.users = users; wyX3qH
} =At" Q6-O
%R?7u'=~
/** 3\}u#/Vb
* @param userService )lLeL#]FLO
* The userService to set. P x Q] $w
*/ !aUYidd
publicvoid setUserService(UserService userService){ v*Gd=\88
this.userService = userService; >D u=(pB
} %]7 6u7b/
} 0#TL$?=|
sTP\}
L~/,;PHN
f$:Y'$Z1
lv/im/]v
上面的代码似乎看不出什么地方设置了page的相关初值,事实上, RYCiO,+
j17h_ a;
可以通过配置文件来进行配置,例如,我想每页显示10条记录,那 `Ns@W?
=cV|o]
么只需要: mmJnE
java代码: %2dzx[s
RdD>&D$I
`,SL\\%u
<?xml version="1.0"?> ~.3v\Q
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork RN 4?]8
s.7=!JQ#]p
1.0//EN" "http://www.opensymphony.com/xwork/xwork- MuMq%uDA"
nxhlTf>3
1.0.dtd"> :y7K3:d3
P9
HKev?y
<xwork> !dwZ` D
nG4ZOx.*1g
<package name="user" extends="webwork- mWZP.w^-
+ Fo^NT
interceptors"> BAXu\a-C_
V5$Gb6?K
<!-- The default interceptor stack name P^"RH&ZQJ
J|{50?S{^
-->
t* Ct*
<default-interceptor-ref "XxmiK
^cNuEF9
name="myDefaultWebStack"/> swZi
O_85
>ymn&_zlT
<action name="listUser" v3cMPN
b||usv[or
class="com.adt.action.user.ListUser"> J:W+'x`@
<param #pPOQv:~
&c!6e<o[p
name="page.everyPage">10</param> vC>2%Zgf-
<result W7A!QS
Ox#vW6;)
name="success">/user/user_list.jsp</result> G7CkP
</action> F-zIzzb&O
OWrQKd
</package> ~vt*%GN3
n.c0G`
</xwork> A^M]vk%dg
bvh#Q_
$"NH{%95}
[err$
x&DqTX?b,
d #1&"(
这样就可以通过配置文件和OGNL的共同作用来对page对象设置初值 >)C7IQ/
\:Tq0|]Px
了。并可以通过随意修改配置文件来修改每页需要显示的记录数。 'z,kxra|n
\5&Mg81
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 ]cP%d-x}
zAM9%W2v_
*w0|`[P+h
xP~GpVhLF
ds+K7B$
我写的一个用于分页的类,用了泛型了,hoho
*~
I HVU
a]fFR~OY
java代码: OEl;R7aOB&
2?%4|@*H?
jj2=|)w$3
package com.intokr.util; 'lE{Nj*7
?jfh'mCA
import java.util.List; ,w6?Ap
4|&/#Cz^Y
/** Czw]5
* 用于分页的类<br> Sak^J.~G[
* 可以用于传递查询的结果也可以用于传送查询的参数<br> ($`IHKF1.l
* _Ycz@Jn
* @version 0.01 /9kxDbj
* @author cheng p@~Y[a =
*/ 7.VP7;jys
public class Paginator<E> { p}sM"}Ul
privateint count = 0; // 总记录数 VRY(@# q
privateint p = 1; // 页编号 1Q
FsT
privateint num = 20; // 每页的记录数 'Up75eT
privateList<E> results = null; // 结果 IY6Ll6OK
2~hdJ/
/** wN'S+4
* 结果总数 @1'OuX^
*/ Z?xaXFm_
publicint getCount(){ &TRKd)w d
return count; aWimg6q
} |-vyhr0
0vLx={i
publicvoid setCount(int count){ 1J1Jp|j.
this.count = count; *A!M0TK?i,
} ~rO&Y{aG#
r6\g#}
/** EsWB |V>
* 本结果所在的页码,从1开始 @F(er
* N)cODy([
* @return Returns the pageNo. uq9mq"
*/ 3(J>aQZuI
publicint getP(){ vcy1itY
return p; 7Fpa%N/WL
} EwG+' nlE
)MI w/
/** HLz<C
* if(p<=0) p=1 :T$}@& -
* \mu';[gLd
* @param p ;p*L(8<YI
*/ @=w)a
publicvoid setP(int p){ "UD)3_R
if(p <= 0) 0y<9JvN$9
p = 1; 9Oj b~
this.p = p; Mz$qe
} >DY/CcG\P
Z(RsB_u5
/** 3F;0a ;[
* 每页记录数量 `2U,#nZ 4
*/ V9<E`C
publicint getNum(){ +,"[0RH
return num; fXnTqKAfu6
} } -4p8Zt
z|AknEE,
/** `m1stK(PO
* if(num<1) num=1
Rq| 5%;1
*/ RgFpc*.T
publicvoid setNum(int num){ M6cybEk`
if(num < 1) n5xG4.#G
num = 1; dk]
this.num = num; (:~_#BA
} N%:uOX8{
7.NL>:lu
/** kKbbsB
* 获得总页数 1G`5FU
*/ o+OX^F0
publicint getPageNum(){ W!8$:Ih_Z
return(count - 1) / num + 1; UE_>@_T
} ZHA&gdK@
24InwR|^
/** .6n|hYe
* 获得本页的开始编号,为 (p-1)*num+1 w0js_P-uv
*/ G2[2y-Rv
publicint getStart(){ 0j;|IU\
return(p - 1) * num + 1; HWoMzp5="3
} #F
.8x@
wAR:GO'n
/** .wm<l:
* @return Returns the results. i-0AcN./p
*/ T06w`'aL
publicList<E> getResults(){ ~:!&