Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 @)8C
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 v]27+/a$c
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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 `24:Eg6r
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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 y/2U:H
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分页支持类: k
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java代码: $RSVN?
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package com.javaeye.common.util; f1>^kl3@P
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import java.util.List; w02HSQ
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publicclass PaginationSupport { 5cQBqH]
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publicfinalstaticint PAGESIZE = 30; UwQ3q
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privateint pageSize = PAGESIZE; tg5jS]O
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privateList items; I_ .;nU1xA
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privateint totalCount; T}]Ao
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privateint[] indexes = newint[0]; .]H]H *wC
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privateint startIndex = 0; o-Idr{
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public PaginationSupport(List items, int 90aPIs-
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totalCount){ cCV"(Oo[H|
setPageSize(PAGESIZE); {Q(6
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setTotalCount(totalCount); "x$S%:p
setItems(items); .Na>BR\F
setStartIndex(0); Q84KU8?d
} W{m0z+N[B
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public PaginationSupport(List items, int O x$|ZEh
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totalCount, int startIndex){ #-HN[U?Gs
setPageSize(PAGESIZE); =\%>O7c,8Y
setTotalCount(totalCount); qryt1~Dq
setItems(items); 3Ob"r`
setStartIndex(startIndex); -;`W"&`ss
} 4+k:j=x
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public PaginationSupport(List items, int 1v\-jM"
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totalCount, int pageSize, int startIndex){ 0RSa{iS*A
setPageSize(pageSize); 4!}fCP ty
setTotalCount(totalCount); >6DY3\
setItems(items); WNYLQ=;
setStartIndex(startIndex); }C&c=3V
} (kuZS4Af
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publicList getItems(){ P/PS(`
return items; ^&rbI,D
} z:G9Uu3H(
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publicvoid setItems(List items){ -5ec8m8
this.items = items; Y)
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} .CpF0
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publicint getPageSize(){ 6Rf5
return pageSize; }b^lg&$(
} ^c7L!F
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publicvoid setPageSize(int pageSize){ ::`j@ ]
this.pageSize = pageSize; GQZUC\cB
} J;kbY9e
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publicint getTotalCount(){ 7=AKQ7BB>b
return totalCount; 5#F+-9r
} `cv:p|s
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publicvoid setTotalCount(int totalCount){ >PJ-Z~O'
if(totalCount > 0){ 5k(#kyP
this.totalCount = totalCount; 68!fcK
int count = totalCount / E0pQRGPA
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pageSize; -oo=IUk
if(totalCount % pageSize > 0) :gVjBF2
count++; (os7Q?
indexes = newint[count]; O9y Q9sl
for(int i = 0; i < count; i++){ 3U`.:w`
indexes = pageSize * `3:%F>
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i; Vi|jkyC8
} m #eD v*
}else{ yEny2q}
this.totalCount = 0; e4b~s
} Mww]l[1'EL
} D{l((t3=T
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publicint[] getIndexes(){ 9$ S,P|
return indexes; u~kwNN9t3
} p{J_d,JH
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publicvoid setIndexes(int[] indexes){ ]
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this.indexes = indexes;
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} v8IL[g6"
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publicint getStartIndex(){ vSA%A47G
return startIndex; 8#Z5-",iw
} HKkf+)%)x
PS22$_}
publicvoid setStartIndex(int startIndex){ ("oA{:@d
if(totalCount <= 0) M5V1j(URE
this.startIndex = 0; g3XAs@
elseif(startIndex >= totalCount) A!kyga6F5
this.startIndex = indexes D+3Y.r9
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[indexes.length - 1]; "p{'984r<
elseif(startIndex < 0) ;Z_C3/b
this.startIndex = 0; eQx"nl3U%
else{ \PONaRK|[z
this.startIndex = indexes $(R)
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[startIndex / pageSize]; kI'A`
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} YM|S<
} J4g;~#_19
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publicint getNextIndex(){ `[&2K@u
int nextIndex = getStartIndex() + N96BWgT
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pageSize; >nDnb4 'C
if(nextIndex >= totalCount) FudD
return getStartIndex(); GvOAs-$
else J":9
return nextIndex; @;}H<&"
} }$1;<
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publicint getPreviousIndex(){ 03o3[g?
int previousIndex = getStartIndex() - 0?xiG SZV
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pageSize; ^BX@0"&-
if(previousIndex < 0) `yZZP
return0; NR&9:?
else *"\Q ~#W
return previousIndex; m[j3s=Gr
} Dj+Osh
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} jPNfLwVkl:
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抽象业务类 5ba[6\Af
java代码: wWU_?Dr_~
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/** nln6:^w
* Created on 2005-7-12 A'1AU:d
*/ R?~h7 d
package com.javaeye.common.business; Z3>xpw G
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import java.io.Serializable; vqOLSE"t*O
import java.util.List; ~!F4JRf
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import org.hibernate.Criteria; [?@wCY4=
import org.hibernate.HibernateException; Xb-c`k~_
import org.hibernate.Session; ,nR8l
import org.hibernate.criterion.DetachedCriteria; D(6x'</>?
import org.hibernate.criterion.Projections; |u r~s$8y-
import YB~t|m65
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org.springframework.orm.hibernate3.HibernateCallback; ~<-
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import V?59.TJ
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org.springframework.orm.hibernate3.support.HibernateDaoS :wZ`>,K"t>
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upport; chmJ|
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import com.javaeye.common.util.PaginationSupport; i: M*L< +
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public abstract class AbstractManager extends Ja v2A6a
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HibernateDaoSupport { pEj^x[b`^
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privateboolean cacheQueries = false; 6//FZ:q
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privateString queryCacheRegion; qf`xH"$
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publicvoid setCacheQueries(boolean !NLvo_[Y
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cacheQueries){ zk'K.!
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this.cacheQueries = cacheQueries; TUUE(sLA
} .q`H`(QM
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publicvoid setQueryCacheRegion(String G7Abhb,
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queryCacheRegion){ eSX[J6
this.queryCacheRegion = !x$:8R
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queryCacheRegion; #;LMtDaL
} xGEmrE<;
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publicvoid save(finalObject entity){ 2\63&C^
getHibernateTemplate().save(entity); 3zTE4pHzu+
} fj-pNl6Gf
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publicvoid persist(finalObject entity){ P%@rH@^Y
getHibernateTemplate().save(entity); :{b6M/
} RmWfV
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publicvoid update(finalObject entity){ fb"J Bc}X
getHibernateTemplate().update(entity); {jM<t
} "bR'Bt
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publicvoid delete(finalObject entity){ 3> \fP#oQ
getHibernateTemplate().delete(entity); uOl(-Zq@
} #W@% K9
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publicObject load(finalClass entity, AX!>l;
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finalSerializable id){ dmaqXsU8q
return getHibernateTemplate().load 60,-\h
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(entity, id); WiNr866nB
} 3 "l
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publicObject get(finalClass entity, jemxky
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finalSerializable id){ +t>*l>[
return getHibernateTemplate().get Q&upxE4-~
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(entity, id); D#d8 ^U
} j!S1Y0CV
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publicList findAll(finalClass entity){ ]CIQq1iY
return getHibernateTemplate().find("from Ep<!zO|
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" + entity.getName()); s`#ntset0
} Q)G!Y
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publicList findByNamedQuery(finalString DhWWN>I
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namedQuery){ J&63Z
return getHibernateTemplate }2Cd1RnS
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().findByNamedQuery(namedQuery); q8?=*1g
} ,TF<y#wed
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publicList findByNamedQuery(finalString query, 7sud/*+F
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finalObject parameter){ 9V=<| 2
return getHibernateTemplate
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().findByNamedQuery(query, parameter); }%!FMXe
} V;iL[
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publicList findByNamedQuery(finalString query, J[}gku?C;
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finalObject[] parameters){ !K3i-zY
return getHibernateTemplate gH{:`E k7
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().findByNamedQuery(query, parameters); Y_[g_
} 5ys#L&q'Z
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publicList find(finalString query){ Gva}J6{
return getHibernateTemplate().find [i(Cl}
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(query); s?^,iQ+tp
} S}.\v<
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publicList find(finalString query, finalObject m x3}m?WQ
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parameter){ oMh~5
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return getHibernateTemplate().find +P[88!
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(query, parameter); Zk]k1]u*5
} 3TU'*w
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public PaginationSupport findPageByCriteria j7@!J7S
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(final DetachedCriteria detachedCriteria){ nU}~I)@V
return findPageByCriteria CV!;oB&
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); gI)w^7Gi
} kF+ZW%6N
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public PaginationSupport findPageByCriteria iD%qy /I/
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(final DetachedCriteria detachedCriteria, finalint A#Xj]^-*
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startIndex){ `GvA241
return findPageByCriteria tCWJSi`IJ
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(detachedCriteria, PaginationSupport.PAGESIZE, cwu$TP A>
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startIndex); C0\%QXu
} t-!Rgg$9
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public PaginationSupport findPageByCriteria g9DG=\*A
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(final DetachedCriteria detachedCriteria, finalint r~)VGdB+
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pageSize, xe(MHNrj
finalint startIndex){ so} l#
return(PaginationSupport) ;e&!
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getHibernateTemplate().execute(new HibernateCallback(){ myD{sE2A
publicObject doInHibernate 1 h<fJzh
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(Session session)throws HibernateException { 3QCMK^#Z:
Criteria criteria = ewo*7j4*
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detachedCriteria.getExecutableCriteria(session); xttYn]T
int totalCount = m+Y@UgB
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((Integer) criteria.setProjection(Projections.rowCount Nt HbwU,
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()).uniqueResult()).intValue(); 0;vtdM[_
criteria.setProjection )nhfkW=e
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(null); %h0D)6j
List items = Am#m>^!qb
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criteria.setFirstResult(startIndex).setMaxResults e:qo_eSC^-
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(pageSize).list(); ,MRvuw0P
PaginationSupport ps = * !X4P
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new PaginationSupport(items, totalCount, pageSize, (%i!%{!]
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startIndex); iNt 4>
return ps; Q5g,7ac8L
} bpGzTU
}, true); HP;|'b
} Wt(Kd5k0'2
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public List findAllByCriteria(final -zprNQW
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DetachedCriteria detachedCriteria){ .Nc_n5D6
return(List) getHibernateTemplate Pow|:Lau!
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().execute(new HibernateCallback(){ \kxh#{$z?
publicObject doInHibernate n9DbiL1{
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(Session session)throws HibernateException { g+.0c=G(
Criteria criteria = T\jAk+$Jo
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detachedCriteria.getExecutableCriteria(session); 02,W~+d1
return criteria.list(); &uPDZ#C-
} &1=g A.ZR
}, true); t{~@I
} rrAqI$6
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public int getCountByCriteria(final gNTh% e
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DetachedCriteria detachedCriteria){ =m~ruZ/
Integer count = (Integer) uw_H:-J
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getHibernateTemplate().execute(new HibernateCallback(){ L/)B}8m\
publicObject doInHibernate )qmFK
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(Session session)throws HibernateException { Ym'7vW#~
Criteria criteria = {b2 aL7
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detachedCriteria.getExecutableCriteria(session); <E SvvTf
return U3/8A:$y
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criteria.setProjection(Projections.rowCount 0#<WOns1
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()).uniqueResult(); aF!WIvir
} M"B@M5KT
}, true); b) Ux3PB
return count.intValue(); ~ibF M5m
} of=ql
} g*F~8+]Y
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用户在web层构造查询条件detachedCriteria,和可选的 $]1qbE+
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 )L >Q;'
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PaginationSupport的实例ps。 %;tJQ%6-.S
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ps.getItems()得到已分页好的结果集 /w0w*nH
ps.getIndexes()得到分页索引的数组 ,aWCiu}
ps.getTotalCount()得到总结果数 T~h.=5
ps.getStartIndex()当前分页索引 t?HF-zQ
ps.getNextIndex()下一页索引 # v+;:
ps.getPreviousIndex()上一页索引 K>$qun?5
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 R1Yqz $#
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,尤其是上面的示例代码,让我着实觉得该对我原来的分页查询做 6P^hN%0
K_Re}\D
一下代码重构了。 ^\T]r<rCY
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我把原本我的做法也提供出来供大家讨论吧: &*A:[b\
[EruyWK
首先,为了实现分页查询,我封装了一个Page类: >O3IfS(l
java代码: V,vc_d?,_o
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/*Created on 2005-4-14*/ oBC]UL;8xJ
package org.flyware.util.page; >e/ r2U
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/** ++0rF\&
* @author Joa [1U{ci&=p
* >MPa38
*/ DL1
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publicclass Page { ~U3Seo }
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/** imply if the page has previous page */ ~2(]ZfO?>H
privateboolean hasPrePage; ]);NnsG
^obC4(
/** imply if the page has next page */ ; [FLT:$
privateboolean hasNextPage; 03Ukw/D&
h\FwgkJP
/** the number of every page */ H#`8Ey
privateint everyPage; #N$9u"8C
c;^A)_/
/** the total page number */ (-J<Vy]
privateint totalPage; R+uw/LG
;?`@"YG)
/** the number of current page */ %4/xH9
privateint currentPage; JRo;(wqZ
Bq;1^gtpe
/** the begin index of the records by the current x9D/s`!
d#8e~
query */ jqtVpNwM
privateint beginIndex; _JA:.V^3gm
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/** The default constructor */ d>/Tu_ y
public Page(){ TL'0T,Jo
}/"4|U
} %/!+(7
D
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/** construct the page by everyPage V)h
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* @param everyPage c 6q/X*
* */ "koo` J
public Page(int everyPage){ *6P'q4)
this.everyPage = everyPage; e=L*&X
} \XDmK
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/** The whole constructor */ H?{MRe
public Page(boolean hasPrePage, boolean hasNextPage, a'A s
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int everyPage, int totalPage, ~of,,&
int currentPage, int beginIndex){ m1V- %kUI
this.hasPrePage = hasPrePage; $
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this.hasNextPage = hasNextPage; d"GDZ[6
this.everyPage = everyPage; JqSr[q
this.totalPage = totalPage; 0
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this.currentPage = currentPage; 9(OAKUQ
this.beginIndex = beginIndex; q :8\e
} K_&_z
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/** 5*1#jiq
* @return 61>f(?s
* Returns the beginIndex. N iISJWk6'
*/ `;/XK,m-
publicint getBeginIndex(){ R"{l[9j4>
return beginIndex; `I#`:hj
} *(Ro;?O,pi
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/** ,5.
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* @param beginIndex |*fNH(8&H
* The beginIndex to set. ,Z5Fea
*/ cd&B?\I
publicvoid setBeginIndex(int beginIndex){ yzg9I
this.beginIndex = beginIndex; y!hi"!
} LuL$v+`
q)k{W>O
/** OfJd/D
* @return Y;g% e3nu
* Returns the currentPage. v#F-<?Vv
*/ 3a^)u-9,x
publicint getCurrentPage(){ mw"}8y
return currentPage; +4HlRGH
} 5us^B8Q
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/** x{?sn
* @param currentPage !t%Q{`p
* The currentPage to set. qK,V$l(4#
*/ 1!1DuQ
publicvoid setCurrentPage(int currentPage){ wHWma)}-z
this.currentPage = currentPage; tUv3jq)n%
} F9O`HFVK
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/** ;AJ<
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* @return `@MPkCy1
* Returns the everyPage. %l;*I?0H
*/ 8,y{q9O
publicint getEveryPage(){ \j:AR4
return everyPage; o X@nP?\
} Q.1XP
E|{m"RUOy
/** 1w17L]4
* @param everyPage ;:?*t{r4#
* The everyPage to set. OW#_ty_ul
*/ b|6 !EGh
publicvoid setEveryPage(int everyPage){ ]zcV]Qj$~
this.everyPage = everyPage; C#h76fpH
} i pwW%"6
qw2)v*Fn
/** XECikld>
* @return #@E(<Pu4`
* Returns the hasNextPage. 4]EvT=Ro
*/ Rf?%Tv0\
publicboolean getHasNextPage(){ /`}6rXnw9
return hasNextPage; g}YToOs
} B*2{M
zsQF,7/}B
/** p7$3`t6u
* @param hasNextPage )tvc/)&A}
* The hasNextPage to set. _0m}z%rI
*/ 5Xj|:qz<(
publicvoid setHasNextPage(boolean hasNextPage){ !?6.!2
this.hasNextPage = hasNextPage; qsTq*G
} "vsjen.K>
V(DjF=8
/** ,6RQvw
* @return !]G jIT]Oh
* Returns the hasPrePage. 0JyqCbl
*/ l@#b;M/
publicboolean getHasPrePage(){ K#@K"N=
return hasPrePage; G>JxIrN0
} J+iX,X
z1FL8=
/** Bd8hJA
* @param hasPrePage nSS}%&a:LX
* The hasPrePage to set. y}Cj#I+a
*/ 0f{IE@-b
publicvoid setHasPrePage(boolean hasPrePage){ C[g&F0 6
this.hasPrePage = hasPrePage; soDfi-2o3
} w0aHEvH/
7>
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/** jOtzx"/)rE
* @return Returns the totalPage. dX0x
Kk%#
* 0S_Ra+e
*/ K)Ge
publicint getTotalPage(){ -CwWs~!
return totalPage; h~:H?pj3g
} [&Lxz~W][
LPMb0F}"5
/** sI$:V7/!
* @param totalPage bje'Oolc
* The totalPage to set. z30= ay1
*/ \wTW?>oZ
publicvoid setTotalPage(int totalPage){ IQ#So]9~Y
this.totalPage = totalPage; |\/~
8qP
} *50ZinfoG
9a-]T=5Ee
} S`4e@Z$
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N]*!8
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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 9z5z
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个PageUtil,负责对Page对象进行构造: Y[T J;O!R
java代码: ,~iFEaV+
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/*Created on 2005-4-14*/ X+\0%|
package org.flyware.util.page; 7@3M]5:3g
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import org.apache.commons.logging.Log; r!>es;R8
import org.apache.commons.logging.LogFactory; lf}?!*V`+
3EAX]
/** N#mK7|\c?:
* @author Joa dfnX!C~6 \
* ]D?oQ$q7
*/ p<ry$=`
publicclass PageUtil { Y/#:)(&@
@i;L Za
privatestaticfinal Log logger = LogFactory.getLog +38Lojb}
+HYN$>
(PageUtil.class); ?|\0)wrRf
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/** 65 NWX8f}
* Use the origin page to create a new page J*/$ywI
* @param page ;I[.
* @param totalRecords zjzqKdy}F
* @return P^i6MZ?
*/ V>DXV-%&C
publicstatic Page createPage(Page page, int 9
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Uzy;#q
totalRecords){ *vEU}SxRuv
return createPage(page.getEveryPage(), xtG)^x!
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page.getCurrentPage(), totalRecords); }Z<D^Z~w
} r@\,VD6J
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/** mOABZ#+Fk
* the basic page utils not including exception 8s\8`2=
x A@|I#
handler =lw4 H_
* @param everyPage 9_I[o.q
* @param currentPage o<9yaQ;
* @param totalRecords _gis+f/8h
* @return page 3(>(lk
*/ `kI?Af*;v
publicstatic Page createPage(int everyPage, int !]n{l_5r
uMljH@xBc
currentPage, int totalRecords){ 2y&_Z^kI?
everyPage = getEveryPage(everyPage); UXXqE4x
currentPage = getCurrentPage(currentPage); zEnC[~W
int beginIndex = getBeginIndex(everyPage, fq)Ohb
mg/C Ux
currentPage); e/g<<f-
int totalPage = getTotalPage(everyPage, Nn~tb2\vk
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totalRecords); &6=TtTp"9
boolean hasNextPage = hasNextPage(currentPage, ^R&_}bp
<T4 7kL I
totalPage); 1mvu3}ewx
boolean hasPrePage = hasPrePage(currentPage); w-{#6/<kI5
/@xr[=L
returnnew Page(hasPrePage, hasNextPage, !8H!Fj`|j
everyPage, totalPage, TPN:cA6[c
currentPage, &VtWSq-)
!07FsPI#{
beginIndex); xF\}.OfWG
}
Ep#<$6>
f=-!2#%
privatestaticint getEveryPage(int everyPage){ zM3H@;}m
return everyPage == 0 ? 10 : everyPage; ;@h'Mb
} 98"z0nI%
f
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privatestaticint getCurrentPage(int currentPage){ n]kQtjJ
return currentPage == 0 ? 1 : currentPage; fS8XuT
} _ d(Ks9
v ](G?L9b
privatestaticint getBeginIndex(int everyPage, int |TNiKy
mYsuNTx!.
currentPage){ O4'kS
@
return(currentPage - 1) * everyPage; NoSqzJyh
} W}<M?b4tP
"OlI-^y
privatestaticint getTotalPage(int everyPage, int ys~p(
GSUOMy[M-
totalRecords){ @ B}c4,
int totalPage = 0; [|m>vY!
&})4?5
if(totalRecords % everyPage == 0) .yHHogbt
totalPage = totalRecords / everyPage; P"h,[{Y*>
else hCOy\[2$
totalPage = totalRecords / everyPage + 1 ; 5Fl
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return totalPage; /(WX!EEsB
} 4IGQ,RTB
HC<BGIgL
privatestaticboolean hasPrePage(int currentPage){ \|b1s @c8
return currentPage == 1 ? false : true; M25z<Y
} f0fqDmn
3qV>TE]6,
privatestaticboolean hasNextPage(int currentPage, [4+a 1/^
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int totalPage){ t0AqGrn
return currentPage == totalPage || totalPage == zN729wK
6{FS/+
0 ? false : true; L;(3u'
} <|>:UGAR
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} 5D02%U2N)G
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2=UTH%1D
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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。 F6neG~Y
%(wsGNd
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 dA M ilTo
7HR%rO?'
做法如下: 7=M'n;!Mh
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 7+2aG
*F4G qX3
的信息,和一个结果集List: 6u]OXPA|
java代码: 80l3.z,:
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s"^YW+HMb
/*Created on 2005-6-13*/ qT-nD}
package com.adt.bo; 3
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F" #3s=
import java.util.List; ju2X*
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dF
import org.flyware.util.page.Page; YQ[&h
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/** 5IF~]5s
* @author Joa ]qP}\+:
*/ %_X[{(
publicclass Result { =w>>7u$4
Wn9Mr2r!*,
private Page page; !?>p]0*<
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private List content; Zn=JmZ
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/** q'8@0FT0
* The default constructor A"T. nqB^y
*/ #}]il0d
public Result(){ 3E2.v5*
super(); fB ,!|u
} 2*",{m
h/y}
/** -r2qIt
* The constructor using fields BKlc{=
* :@4>}k*
* @param page . L6@Rs
* @param content y7L4jO9h
*/ >A@D;vx
public Result(Page page, List content){ >~bj7M6t
this.page = page; gZ%O<XO
this.content = content; z(#hL-{c
} #,9TJ:~N
7J_f/st
/** YNQ6(HA
* @return Returns the content. vYm&AD
*/ LkbvA
publicList getContent(){ v}*u[GWl]
return content; N)I
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} PHL@1K{)
CzsY=DBH=
/** Dp |FyP_w
* @return Returns the page. EQ`t:jc{
*/ aiX;D/t?
public Page getPage(){ DO,&Foh\
return page; S/:QVs
} e ~,'|~
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/** &^D@(m7>{K
* @param content ~E|V{z%
* The content to set. G78j$
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*/ %_=R&m'n`
public void setContent(List content){ U=#ylQ
this.content = content; o 0
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} U$JIF/MO_
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/** >\x
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* @param page X|B;>q
* The page to set. < 3+&DV-<N
*/ h}<ZZ
publicvoid setPage(Page page){ 5Cyjq0+
this.page = page; t4c#' y
} h9smviU7u
} J#Ehx|
bvRGTOxO
EuA<{%i
kxf=%<l
x{o5Ha{
2. 编写业务逻辑接口,并实现它(UserManager, [jn;|
3
,ST.pu8N.
UserManagerImpl) M@@O50~
java代码: O,Gn2Do
v23Uh2[@Yy
0!\q
/*Created on 2005-7-15*/ xVX||rrh
package com.adt.service; ^aWNtY'
:
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import net.sf.hibernate.HibernateException; O;t?@!_
G6bg ~V5Q:
import org.flyware.util.page.Page; ~*]`XL.-
tBUQf*B
import com.adt.bo.Result; t"vO&+x
Z6@J-<u
/** 'yjH~F.
* @author Joa ]+7c1MB(5
*/ O +}EE^*a
publicinterface UserManager { Rw8m5U
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public Result listUser(Page page)throws Ou,_l
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HibernateException; z6r/
w
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} d+ko"F|
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Hxi=\2-
Y.
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java代码: PzkXrDlB7
fsuvg jlE
yyDBW`V((
/*Created on 2005-7-15*/ ZU'^%)6~o~
package com.adt.service.impl; fOervo
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import java.util.List; ,X6j$YLWp
x^skoz
import net.sf.hibernate.HibernateException; '
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;CBdp-BUj
import org.flyware.util.page.Page; `I{Q,HQ7
import org.flyware.util.page.PageUtil; c)fp;^
vBnHG-5;P
import com.adt.bo.Result; 6u;(R0n
import com.adt.dao.UserDAO; umn^QZ,
import com.adt.exception.ObjectNotFoundException; V3UGx'@^y
import com.adt.service.UserManager; `:O.g9
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/** :[03upyS
* @author Joa .LHe*J C
*/ 7E)7sd
publicclass UserManagerImpl implements UserManager { a[ l5k
mj|9x1U)
private UserDAO userDAO; dq(L1y870
e1Hx"7ew_
/** K a|\gl;V
* @param userDAO The userDAO to set. 3vD,hL`&
*/ >f8,YisH
publicvoid setUserDAO(UserDAO userDAO){ !2I wuru
this.userDAO = userDAO; ?\r3
_
} }`FPe
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/* (non-Javadoc) *4y r7~S5
* @see com.adt.service.UserManager#listUser tpK4 gjf
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(org.flyware.util.page.Page) !,"G/}'^;
*/ axOy~%%c
public Result listUser(Page page)throws ir#^5e@
0VPa;{i/
HibernateException, ObjectNotFoundException { zy;w07-)
int totalRecords = userDAO.getUserCount(); u;}B4Rx
if(totalRecords == 0) E1_4\S*z
throw new ObjectNotFoundException hDsORh!i
#Qd3A
("userNotExist"); :nEV/"#F
page = PageUtil.createPage(page, totalRecords); &X(-C9'j
List users = userDAO.getUserByPage(page); zt0 zKXw
returnnew Result(page, users); DboqFh#]=h
} |;yb *
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} Pc1N~?}.
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4/|=0TC;
hBu=40K
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 =p6xc}N
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询,接下来编写UserDAO的代码:
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3. UserDAO 和 UserDAOImpl: %}:J
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java代码: 5yI D%
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X9HI@M]h
/*Created on 2005-7-15*/ OpQa!
package com.adt.dao; IIZsN*^
hg @Jpg
import java.util.List; 9n7d
"XD2
0<9TyN6
import org.flyware.util.page.Page; B"v=Fr[
[4e5(!e
import net.sf.hibernate.HibernateException; uX[
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/** +n dyR
* @author Joa r
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*/ D6WsEd>
publicinterface UserDAO extends BaseDAO { \2!$HA7P
U_No/$ b
publicList getUserByName(String name)throws ND>}t#^$
_#:1Axx1
HibernateException; 0*^Fk=>ej
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publicint getUserCount()throws HibernateException; n21J7;\/+
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publicList getUserByPage(Page page)throws #UQ[8e
sh1()vT
HibernateException; U|nk86r
9@06]EI_
} ,R+u%bmn#
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1F|+4
UsTPNQj
/rW{rf^
java代码: <4g^c&
Up&q#vqIj
/v[-KjTj7
/*Created on 2005-7-15*/ :w+Rs+R
package com.adt.dao.impl; _c2#
;l'I.j
import java.util.List; :-)[B^0
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import org.flyware.util.page.Page; V_* ^2c)
OBZj-`fq J
import net.sf.hibernate.HibernateException; X#y l8k_
import net.sf.hibernate.Query; @!$NUY8,A#
rxARJso
import com.adt.dao.UserDAO; &%lhov
0CROq}
/** ;
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* @author Joa @4i DN
*/ j4h 7q<
public class UserDAOImpl extends BaseDAOHibernateImpl MYDSkW
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implements UserDAO { e9d~Xi16KY
M<"D!h9YP
/* (non-Javadoc) l-
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* @see com.adt.dao.UserDAO#getUserByName B.?yHaMI[
iJi|* P5dw
(java.lang.String) m_B5M0},
*/ vF,l?cU~
publicList getUserByName(String name)throws hk
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HibernateException { RC 48e._t
String querySentence = "FROM user in class ~&x%;cnv_
L2qF@!Yy=
com.adt.po.User WHERE user.name=:name";
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Query query = getSession().createQuery Ij+zR>P8=\
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(querySentence); }5k"aCno
query.setParameter("name", name); $sJn:
8z
return query.list(); ,>$#e1!J
} md0=6<
}P
VV
/* (non-Javadoc) 1f=L8Dr
* @see com.adt.dao.UserDAO#getUserCount() n>HN py
*/ Vr*t~M>
publicint getUserCount()throws HibernateException { 1}6pq2
int count = 0; +K?h]v]%
String querySentence = "SELECT count(*) FROM ')BQ 0sg
so7;h$h!H
user in class com.adt.po.User"; ld
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Query query = getSession().createQuery !o@-kl
t]x HM
(querySentence); EVf'1^f
count = ((Integer)query.iterate().next ciTQH (G
k=@Q#=;*[W
()).intValue(); C$bK!]a
return count; g=pDC+
} /Yh8r1^2tZ
%Y@3)
/* (non-Javadoc) 8^{BuUA
* @see com.adt.dao.UserDAO#getUserByPage mT.F$Y9
*=v
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(org.flyware.util.page.Page) h2q]!01XP
*/ 5?b9[o+D
publicList getUserByPage(Page page)throws 9K49<u0O
c_iF S
HibernateException { \c]/4C +/
String querySentence = "FROM user in class 1$^{Uma
;[xDc>&("Q
com.adt.po.User"; )"1D-Bc\Q
Query query = getSession().createQuery
<ygO?m{
"CaVT7L
(querySentence); en
query.setFirstResult(page.getBeginIndex()) $OT:J
.setMaxResults(page.getEveryPage()); H.9 J}k1S
return query.list(); gor6c3i
} ZD,l2DQ?
8[DD=[&
} 4MM#\
!-QKh aY
Rwr0$_A
F4}Zl
;#;X@BhS
至此,一个完整的分页程序完成。前台的只需要调用 gQ?k}D
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userManager.listUser(page)即可得到一个Page对象和结果集对象 s#Le`pGoW
Ev()2 80
的综合体,而传入的参数page对象则可以由前台传入,如果用 %$cwbh-{{
ecHy. 7H
webwork,甚至可以直接在配置文件中指定。 ?eu=0|d
3] !(^N>V
下面给出一个webwork调用示例: r[gV`khka
java代码: .,c8cq?
;7hf'k
rdK.*oT
/*Created on 2005-6-17*/ a%AU9?/q#
package com.adt.action.user; C{c (K!
:70oO}0m.
import java.util.List; u4S3NLG)
H`y- "L8q
import org.apache.commons.logging.Log; D1w_Vpz
import org.apache.commons.logging.LogFactory; :>,d$f^tqE
import org.flyware.util.page.Page; 3{%/1>+x5
D\k);BU~
import com.adt.bo.Result; Ki' EO$
import com.adt.service.UserService; 0trFLX
import com.opensymphony.xwork.Action; ';1
c
q%JV"9,
/** YFW+l~[#
* @author Joa n\ IVpgP
*/ YB 4R8}4
publicclass ListUser implementsAction{ T1x$v,)8x
F;zmq%rK
privatestaticfinal Log logger = LogFactory.getLog tHGK<rb
7.5G4
(ListUser.class); Dk4Wj"LS
ZK13[_@9
private UserService userService; Z?GC+hG`
hP7nt
private Page page; <q!{<(:
>uQ!B/C!
privateList users; 9u:MF0:W
{_
#
/* 74KFsir@
* (non-Javadoc) )X@(>b{
* wHAh6lm
* @see com.opensymphony.xwork.Action#execute() ]Rw,5\0
*/ k<:!^_3H
publicString execute()throwsException{ D`LwW` 9
Result result = userService.listUser(page); rz3&khi
page = result.getPage(); _rajm J
users = result.getContent(); :dK%=j*ZK
return SUCCESS; C6Kz6_DQZ
} i P/I% D
wo*/{KFvh
/** @50Js3R1q
* @return Returns the page. v.\&gn