Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 csjCXT=Ve
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 b!4Z~d0=
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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 #V$h?`qhwr
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自于Quake Wang的javaeye-core包的相应类,然后又做了很多修改 K0fuN)C
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。 1smKU9B2)
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分页支持类: [/Sk+ID
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java代码: s H(io
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package com.javaeye.common.util; (yK@(euG
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import java.util.List; I~F]e|Ehqr
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publicclass PaginationSupport { g#%Egb1
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publicfinalstaticint PAGESIZE = 30; ]%2y`Jrl^W
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privateint pageSize = PAGESIZE; VOSq%hB
z 4qEC
privateList items; uGpLh0
8 RA
privateint totalCount; -2B3 xIZJ
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privateint[] indexes = newint[0]; 25Uw\rKeO
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privateint startIndex = 0; xnOd$]
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l
public PaginationSupport(List items, int ?0tm{qP
y>>)Yo&|
totalCount){ *cP(3n3]R
setPageSize(PAGESIZE); P%aNbMg
setTotalCount(totalCount); ?*^HZ~O1
setItems(items); 37b6w6{D
setStartIndex(0); 5t,X;
} VDFs.;:s
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public PaginationSupport(List items, int 8?hZ5QvA(j
l4gZHMh'
totalCount, int startIndex){ #.{ddY{
setPageSize(PAGESIZE); kgHZaQnD
setTotalCount(totalCount); ?kULR0uL+
setItems(items); W3gHzT?{
setStartIndex(startIndex); "&C>=
} O>"T*
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public PaginationSupport(List items, int _>J`e7j+
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totalCount, int pageSize, int startIndex){ f^)iv
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setPageSize(pageSize); WD@v<Wx)
setTotalCount(totalCount); =Eb$rc)
setItems(items); &$heW,
setStartIndex(startIndex); [jR>.H'
} 0Ibe~!EiQJ
b}&.IJ&40j
publicList getItems(){ /@64xrvIl=
return items; VwKfM MI8
} I7HGV(
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publicvoid setItems(List items){ Vn65:" O
this.items = items; M(1cf(<+
} n_(f"Uv
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publicint getPageSize(){ $DdC|gMK
return pageSize; R|92T*h
} ;`h$xB(
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publicvoid setPageSize(int pageSize){ Y;"jsK{$
this.pageSize = pageSize; PJT$9f~3;.
}
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publicint getTotalCount(){ L d{`k
return totalCount; |AXV4{j_i
} @RZbo@{~
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publicvoid setTotalCount(int totalCount){ fohZ&f|>
if(totalCount > 0){ DzIV5FG
this.totalCount = totalCount; 1)3'Y2N*
int count = totalCount / Wuk!\<T{
$Wu|4]o>9
pageSize; .kTOG'K\e
if(totalCount % pageSize > 0) ;ojJXH~$}
count++; 8)>4ZNXz
indexes = newint[count]; ?<rZ9$
for(int i = 0; i < count; i++){ ?Y 5Vje[^
indexes = pageSize * 6~l+wu<$
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i; NiMsAI@j
} kQp*+ras
}else{ )NK#}c~5
this.totalCount = 0; 2FY]o~@
} =y >CO:^G%
} \Xe{vlo>h
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publicint[] getIndexes(){ Tb!FO"o
return indexes; dA^{}zZu
} ;oO_5[,M
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publicvoid setIndexes(int[] indexes){ Tz~a. h@
this.indexes = indexes; 6E2#VT>@/
} ??P%.
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publicint getStartIndex(){ X3][C
return startIndex; uqD|j:~ =k
} s@E)=;!
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publicvoid setStartIndex(int startIndex){ #.vp\W
if(totalCount <= 0) 2D a0*xn{
this.startIndex = 0; 4,f`C0>"
elseif(startIndex >= totalCount) x=-(p}0o;<
this.startIndex = indexes DXFDs=u
&?TXsxf1Zh
[indexes.length - 1]; do9~#F
elseif(startIndex < 0) "Th;YJu
this.startIndex = 0; * \B(-
else{ 6ma.FvSIM
this.startIndex = indexes A]1dR\p
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[startIndex / pageSize]; I%($,kd}s
} U5OFw+J
} #M<YNuE#"
M& )yr^
publicint getNextIndex(){ i(ZzE
int nextIndex = getStartIndex() + z "z
Mf !S'\
pageSize; f@q.kD21
if(nextIndex >= totalCount) *^Ro I
return getStartIndex(); %&0/Ypp=
else ~YenH
return nextIndex; TRJTJM_k
} M`7[hr
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publicint getPreviousIndex(){ lANi$
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int previousIndex = getStartIndex() - 2jlz#Sk
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pageSize; -d thY(8
if(previousIndex < 0) 9g#
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return0; "a(e2H2&T4
else (zxL!ZR<
return previousIndex; F+?i{$
} XfflD9M
RCi8{~rIvS
} cP4C<UG
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9Zf
抽象业务类 CEBu[TT/9
java代码: ]1eZ<le`6
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/** \t`Vq JLyu
* Created on 2005-7-12 I8 [
*
*/ bSn={O"M
package com.javaeye.common.business; rCsC}2O
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import java.io.Serializable; TtnJ
u*
import java.util.List; =T#hd7O`V
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import org.hibernate.Criteria; ,1cpV|mAr
import org.hibernate.HibernateException; 2Nx:Y+[
import org.hibernate.Session; 6)W8H X~+
import org.hibernate.criterion.DetachedCriteria; wkx #WC
import org.hibernate.criterion.Projections; LpI4R
import 2Dt^W.!
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org.springframework.orm.hibernate3.HibernateCallback;
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import >;F}>_i
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M
org.springframework.orm.hibernate3.support.HibernateDaoS \){_\{&
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upport; .gNziDO
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import com.javaeye.common.util.PaginationSupport; PW iuM=E
.:4*HB
public abstract class AbstractManager extends j?T>S]xOX
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HibernateDaoSupport { vl6|i)D
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privateboolean cacheQueries = false; &;WK=#
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privateString queryCacheRegion; U>00B|<GJ
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publicvoid setCacheQueries(boolean >wL!`:c'"
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cacheQueries){ MRZN4<}9
this.cacheQueries = cacheQueries; ZsCwNZR
} Nf2lw]-G4
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publicvoid setQueryCacheRegion(String :7X{s4AU6
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queryCacheRegion){ ,aq>9\pi
this.queryCacheRegion = +fKV/tSWi
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queryCacheRegion; %rf6>
} /VP #J<6L
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publicvoid save(finalObject entity){ tUW^dGo.
getHibernateTemplate().save(entity); 6i~<,;Cn
} UUM:*X
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publicvoid persist(finalObject entity){ :8hX kQ
getHibernateTemplate().save(entity); &j/,8 Z*
}
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publicvoid update(finalObject entity){ O'xp" e,
getHibernateTemplate().update(entity); Os].
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} 44w
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publicvoid delete(finalObject entity){ Xr4k]'Mg
getHibernateTemplate().delete(entity); s jaaZx1
} <lU(9)
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publicObject load(finalClass entity, LaZ
@4/z!
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finalSerializable id){ S$P=;#r
return getHibernateTemplate().load ;9-J=@KY4
0,):;OI
(entity, id); jq_4x[
} sFvYCRw
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publicObject get(finalClass entity, [9}<N2,9z
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finalSerializable id){ ,%zE>^~
return getHibernateTemplate().get 3h%Nd&_9
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(entity, id); YguW2R=6]
} FPZ@6
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publicList findAll(finalClass entity){ "(~fl<;
return getHibernateTemplate().find("from |5q,%9_
D vN0h(?
" + entity.getName()); paYS<8In
} ep`8LQf
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publicList findByNamedQuery(finalString _5b~3K/V
n:?a=xY
namedQuery){ &uV|Ie8@q
return getHibernateTemplate jROh3kq
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().findByNamedQuery(namedQuery); ^vzXT>t-M
} [Z;H=`
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publicList findByNamedQuery(finalString query, >}C:EnECy
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finalObject parameter){ (y\.uPu!
return getHibernateTemplate P!)F1U]!
hv#LKyp%
().findByNamedQuery(query, parameter); ^)$T`
} vfVF^
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publicList findByNamedQuery(finalString query, e(OKE7
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finalObject[] parameters){ [iyhrc:@
return getHibernateTemplate xk,1D
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().findByNamedQuery(query, parameters); bGwj` lue
} 31%3&B:Ts
l Dwq[ I]w
publicList find(finalString query){ 9\E];~"iP
return getHibernateTemplate().find *$JS}Pax
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(query); <~svy)Cz
} #"H<k(-Cz
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publicList find(finalString query, finalObject _0\wyjjU
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parameter){ eSW}H_3
return getHibernateTemplate().find ;L$l0(OO
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(query, parameter); cA]PZ*]{BN
} 5twG2p8
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public PaginationSupport findPageByCriteria
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(final DetachedCriteria detachedCriteria){ _?bF;R
return findPageByCriteria EU Oa8Z
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); D6\k}4n-
} Tv%
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public PaginationSupport findPageByCriteria <BBSC
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(final DetachedCriteria detachedCriteria, finalint 9/R=_y-
,ob)6P^rw
startIndex){ Q%V530
P;
return findPageByCriteria u2U+uD@yA
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(detachedCriteria, PaginationSupport.PAGESIZE, ? fM_Y
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startIndex); PA,\o8]x
} [LbCG
=#%Vs>G
public PaginationSupport findPageByCriteria =jU#0FAO
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(final DetachedCriteria detachedCriteria, finalint aLQ]2m
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pageSize, u1Wixjd|
finalint startIndex){ H~0B5Hl!F
return(PaginationSupport) t-]~^s
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getHibernateTemplate().execute(new HibernateCallback(){ )Oj{x0{\Q
publicObject doInHibernate SK,UW6h
,twm)%caU
(Session session)throws HibernateException { =}F$r5]
Criteria criteria = qx?0]!x
e\*N Lj_(
detachedCriteria.getExecutableCriteria(session); """eU,"
int totalCount = E1qf N>0Z
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((Integer) criteria.setProjection(Projections.rowCount X}&Y(kOT
g zyi'K<
()).uniqueResult()).intValue(); >kDkv g1"
criteria.setProjection Cv]$w(k
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(null); d! _8+~
List items = r+h$]OJ
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criteria.setFirstResult(startIndex).setMaxResults 1%N[DA^<\
jF{\=&fU
(pageSize).list(); ksAu=X:
PaginationSupport ps = njb{
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new PaginationSupport(items, totalCount, pageSize, O[9A} g2~
,sp( (SF]1
startIndex); qa?0GTAS
return ps; %
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} d{]2Q9g
}, true); ?T'a{~]R
} h$ $i@IO0
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public List findAllByCriteria(final PD:lI]:s
m=^ihQ
DetachedCriteria detachedCriteria){ X`k#/~+0
return(List) getHibernateTemplate OkQtM
nq
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().execute(new HibernateCallback(){ 8fb<hq<
publicObject doInHibernate a0&R! E;
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(Session session)throws HibernateException { XILreATK@
Criteria criteria = z'k@$@:0XD
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detachedCriteria.getExecutableCriteria(session); L#u!T)!zW
return criteria.list(); m Wh
} aByd,uSe)_
}, true); IoHYY:[-
} wf,w%n
()(/9t
public int getCountByCriteria(final VCvFCyAz
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DetachedCriteria detachedCriteria){ 0JV|wd8j
Integer count = (Integer) "pQ)5/e
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getHibernateTemplate().execute(new HibernateCallback(){ 5uL!Ae
publicObject doInHibernate lXu6=r
tS3{y*yi
(Session session)throws HibernateException { >8w=Vlp
Criteria criteria = -D^v:aC
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detachedCriteria.getExecutableCriteria(session); SG-Xgr@
return ?w>-ya
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criteria.setProjection(Projections.rowCount `SG8w_
::p(ViYG
()).uniqueResult(); !mu1e=bY>
} f9?f!k
}, true); =(p]L
return count.intValue(); dC8,
} ,<]~/5-f
} U
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用户在web层构造查询条件detachedCriteria,和可选的 nT/Azg
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 M IR))j;
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PaginationSupport的实例ps。 OEXa^M4x
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ps.getItems()得到已分页好的结果集 rHD_sC*
ps.getIndexes()得到分页索引的数组 lVo}DFZ
ps.getTotalCount()得到总结果数 'zfj`aqc
ps.getStartIndex()当前分页索引 *n2le7
ps.getNextIndex()下一页索引 ~zL DLr=
ps.getPreviousIndex()上一页索引 K]C@seF`
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 Tu_4kUCR!f
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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 6"u"B-cz
iJ!p9E*(
一下代码重构了。 k/2TvEV3=
-=a,FDeR
我把原本我的做法也提供出来供大家讨论吧: nn{PhyK
^?-wov$
首先,为了实现分页查询,我封装了一个Page类: 4-~S"T8<u
java代码: roHJ$~q?
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/*Created on 2005-4-14*/ Ql{:H5
package org.flyware.util.page; h0;R*c
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/** 0{!+N6MiR
* @author Joa @XN|R
* M|}V6F_y
*/ L<[%tv V
publicclass Page { y5`$Aa4~
9;`E,w
/** imply if the page has previous page */ <@J0
770
privateboolean hasPrePage; ECr}7R%
xpB*>zb
/** imply if the page has next page */ Wr;9Mz&{
privateboolean hasNextPage; -5d^n\CDK
J @^Ypq
/** the number of every page */ #B!<gA$/
privateint everyPage; t lpTq\;
Ula
h!s
/** the total page number */ *8I &|)x
privateint totalPage; 8Ao pI3
W|AK"vf
/** the number of current page */ GVld]ioycG
privateint currentPage; agp7zw=N
EdC/]
/** the begin index of the records by the current tM3Q;8gB!
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query */ ['Y"6[1
privateint beginIndex; '))K'
u
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/** The default constructor */ J)._&O$
public Page(){ 0Q!/A5z
!YENJJ
} cN%@
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/** construct the page by everyPage _o'a|=Osx>
* @param everyPage g1&>.V}!
* */ F-%Hw
public Page(int everyPage){ T*jQzcm~?
this.everyPage = everyPage; h8hyQd$!
} <N,:w`g#
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/** The whole constructor */ uo-1.[9ds
public Page(boolean hasPrePage, boolean hasNextPage, eNu]K,rT
@|EWif|
sr-tZ^d5S?
int everyPage, int totalPage, e&-MP;kgW9
int currentPage, int beginIndex){ Fuy"JmeR
this.hasPrePage = hasPrePage; Wg\MaZ6Di
this.hasNextPage = hasNextPage; BI+x6S>d
this.everyPage = everyPage; P`AW8Y6o
this.totalPage = totalPage; =2e{T J/
this.currentPage = currentPage; ~'w]%rh!
this.beginIndex = beginIndex; fxknfgbg
} UT_kw}1o
,ut7`_Fy
/** kc/"
* @return \HQw$E/p
* Returns the beginIndex. B,U|V
*/ YT'olk
publicint getBeginIndex(){ P71] Z
return beginIndex; _f"KB=A_x
} rVZl v3
tP4z#0r2
/** 9xaieR
* @param beginIndex REWW(.3o
* The beginIndex to set. =d#(n M*
*/ [,sm]/Xlc
publicvoid setBeginIndex(int beginIndex){ jr/IU=u*v
this.beginIndex = beginIndex; "P
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} wWQt
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/** NK6~qWsu
* @return zx7A}rs3oX
* Returns the currentPage. "xAIK
*/ [C{oj*"c]
publicint getCurrentPage(){ 3 L:SJskYR
return currentPage; mwO9`AU;
} ujS C
w_#C8}2
/** ){*9$486
* @param currentPage epgAfx-_OH
* The currentPage to set. & tjL*/
*/ 7ygz52
publicvoid setCurrentPage(int currentPage){ Vp&"[rC_z
this.currentPage = currentPage; M}]4tAyT
} N"s"^}M\
Jw0I$W/
/** Zmm6&OZ%
* @return kK=f@l
* Returns the everyPage. mcTC'. 9
*/ E8L\3V4
publicint getEveryPage(){ lUd4`r"
return everyPage; [*1:?mD$
} M)3'\x:
2=7:6Fw
/**
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* @param everyPage : +f6:3
* The everyPage to set. +]p/.-Uw
*/ E]W
:
publicvoid setEveryPage(int everyPage){ ~d-Q3n?zR
this.everyPage = everyPage; + cZC$lo
} kgd
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/** {t|Q9&
* @return =!u]t&yv
* Returns the hasNextPage. gts09{"}Y
*/ kn+@)3W:*
publicboolean getHasNextPage(){ |E&|6h1
return hasNextPage; v%7Gh-P
} W@RD
bsc
Z-3("%_$/
/** w|f@sB>j
* @param hasNextPage .|@2Uf
* The hasNextPage to set. duc\/S'
*/ q);oO\<
publicvoid setHasNextPage(boolean hasNextPage){ 0{/'[o7
this.hasNextPage = hasNextPage; Wr`<bLq1vs
} m -0}Pe9L
mQ3gp&d3W
/** 5w5"rcV
* @return 0E9 lv"3o
* Returns the hasPrePage. ,/Q`gRBh"
*/ hqa6aYY x
publicboolean getHasPrePage(){ <5zr|BTF]F
return hasPrePage; `>=@Kc
} m[v%Qe|~
r`i.h ^2De
/** 8X/SNRk6p
* @param hasPrePage vAjog])9s
* The hasPrePage to set. h+w1 D} *
*/ f|Nkk*9$
publicvoid setHasPrePage(boolean hasPrePage){ >M^:x-mib
this.hasPrePage = hasPrePage; >sQf{uL
} q#K0EAgC
mR$0Ij/v
/** O"1HO[
* @return Returns the totalPage. S[{,+{b0
* Y.kc,~vYL
*/ /#j)GlNp:
publicint getTotalPage(){ ` 5n^DP*X
return totalPage; SeuDJxqopD
} !&5|:96o
89t"2|9 u
/** /Mj|Px%
* @param totalPage 2fXwJG'
* The totalPage to set. 8!
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*/ Zzmo7kFx3
publicvoid setTotalPage(int totalPage){ ZCA= n
this.totalPage = totalPage; @2`nBtk
} n g9_c
Wu/:ES)C
} `|mV~F|
c*i,z
\eAV: qV
J!">L+Zcx
js!C`]1
上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 Kd\d>&b
X9?0`6Li
个PageUtil,负责对Page对象进行构造: }GHCu
java代码: ?5F;4oR2g
3Kq/V_
ru|*xNXKgC
/*Created on 2005-4-14*/ h-x~:$Z,
package org.flyware.util.page; 5g.Kyj|
g ;XK3R
import org.apache.commons.logging.Log; GyVuQ51
import org.apache.commons.logging.LogFactory; g?*D)WU
TP/bX&bjCy
/** nRT]oAi
* @author Joa ])q,mH
* ]YOWCFAQot
*/ /m i&7C(6
publicclass PageUtil { ?Ss~!38
S+*>""=
privatestaticfinal Log logger = LogFactory.getLog ,$U~<Zd
!pHI`FeAV
(PageUtil.class); mQ9shdvt-
'T7Y5X80$j
/** UID`3X
* Use the origin page to create a new page bfYVA2=Z
* @param page L-zU%`1{M
* @param totalRecords 3Bcv"O,B!{
* @return u|k_OUTq
*/ y
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publicstatic Page createPage(Page page, int (W }DMcuSd
\f=kQbM
totalRecords){ =5:S"WNj
return createPage(page.getEveryPage(), 7 4&{GCL
"'/+}xM"5
page.getCurrentPage(), totalRecords); ; P$ _:-C
} qn'TIE.
Sr_hD5!
/** F{_,IQ]U
* the basic page utils not including exception 0g; o6Fg
I!Mkss xc
handler J*m7
d4^
* @param everyPage igEqty!.
* @param currentPage 0uIBaW3s
* @param totalRecords Vv+ oq5hf
* @return page 7]~|dc(
*/ <9T,J"y
publicstatic Page createPage(int everyPage, int b
`bg`}x
+;=>&XR0m
currentPage, int totalRecords){ /c6]DQ<?
everyPage = getEveryPage(everyPage); o)$eIu}Wg
currentPage = getCurrentPage(currentPage); 8VuLL<\|
int beginIndex = getBeginIndex(everyPage, -B(p8 YH
1QnaZhu'
currentPage); ):A.A,skf
int totalPage = getTotalPage(everyPage, _;:_ !`
[;o>q;75Jz
totalRecords); nc1?c1s,f
boolean hasNextPage = hasNextPage(currentPage, vZs~=nfi#|
jVHS1Vsei
totalPage); l3/Cj^o4
boolean hasPrePage = hasPrePage(currentPage); }*O8]lG
8 qZbsZi4
returnnew Page(hasPrePage, hasNextPage, O@w_"TJP/z
everyPage, totalPage, PWquu`
currentPage, u9u'5xAO
U??OiKVZ+
beginIndex); `:jF%3ks+0
} e)}=T0
s
TtQd#mSI\
privatestaticint getEveryPage(int everyPage){ a^ys7UV
return everyPage == 0 ? 10 : everyPage; ~yV?*"Hi
} 1=ZQRJW0B
1^ go)(Mx
privatestaticint getCurrentPage(int currentPage){ }lCQ+s!
return currentPage == 0 ? 1 : currentPage; bH :C/P<x
} 5+j):_
&JD^\+7U:
privatestaticint getBeginIndex(int everyPage, int Qz_4Ms<o
[57`V&c5
currentPage){ x<@i3Y{[
return(currentPage - 1) * everyPage; 7]i6 Gk
} 8dJ+Ei~M
.9Dncsnf,`
privatestaticint getTotalPage(int everyPage, int N9M",(WTt}
Vup|*d2r0E
totalRecords){ -KfMKN~
int totalPage = 0; Og8%SnEpMI
JXR]G
if(totalRecords % everyPage == 0) 1/6}E]-F
totalPage = totalRecords / everyPage; Cv4nl7A'
else $iA:3DM07
totalPage = totalRecords / everyPage + 1 ; ~PU}==*q
kV8qpw}K
return totalPage; 3C'6i
} $vn)(zn+
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privatestaticboolean hasPrePage(int currentPage){ fZ^ad1o
return currentPage == 1 ? false : true; ~y
whl'"k
} ] ;HCt=I~
J4
U]_|
privatestaticboolean hasNextPage(int currentPage, IGab~`c-[
DJqJ6 z:'
int totalPage){ zsR5"Vi=
return currentPage == totalPage || totalPage == =.JcIT'
c>Ri6=C
0 ? false : true; =Lnip<t>ja
} sM%l:Fv
8-cuaa
qv|}>wU
} (m=1yj9
E b CK9
A"R(?rQi=
g1]bI$;
P\QbMj1U
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。 %;<g!Vw.k
L|;sB=$'{
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 ZF8`=D`:R
aSgKh
做法如下: vj]h[=:
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 NgF"1E
bQ&%6'ck
的信息,和一个结果集List: pd.unEWwF
java代码: g`tV^b")
x|()f3{.
Md8<IFi9]Q
/*Created on 2005-6-13*/ P8;1,?ou
package com.adt.bo; A]drNFE
QXO~DR1
import java.util.List; T[c-E*{hR
.C5JQO
import org.flyware.util.page.Page; zz(EH<>
z\?<j%e!t
/** #B#xSmak
* @author Joa PzhC *" i}
*/ 2U"2L^oKI
publicclass Result { :JZV=@<T
#7}YSfm^6
private Page page; xr7M#n
a`?Vc}&
private List content;
5PC:4
MD3iWgM
/** ^&$86-PB/
* The default constructor Tks"GlE*D
*/ '$J M2 u
public Result(){ {)
sE;p-
super(); 1'8-+?r
} mgM"u94-]
xO,;4uE
/** ]KG.-o30
* The constructor using fields h~z}NP
* u0g"x_3
* @param page L{&=SR.
* @param content Vo%Z|
*/ Q/*|ADoq
public Result(Page page, List content){ 1+Ik\
this.page = page; VUz+_)
this.content = content; FN (O
} [,MK)7DU
0"ooHP$1
/** Ww#!-,*]o
* @return Returns the content. +Yc@<$4
*/ wjgF e]
publicList getContent(){ Z)@[N
6\?
return content; >ffC?5+
} 9]1LwX!M2
*X}2
/** s#")hMJQ
* @return Returns the page. D(&WEmm\B
*/ F~bDg tN3
public Page getPage(){ Kc#1H|'2N
return page; `R -?+76?
} U3 UA
'#.D`9YI<
/** tDfHO1pS
* @param content 475g-t2"@
* The content to set. -w5sXnS
*/ Iek]/=
public void setContent(List content){ %T\2.vl
this.content = content; J8Vzf$t};
} acQHqR
jB0Ts;5
/** _{eA8J(A<
* @param page G-;EB
* The page to set. ?du*ITim
*/ '
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publicvoid setPage(Page page){ v\?l+-A?y
this.page = page; ;cp||uO
} CVEo<Tz
} 82?LZ?!PD
@L0)k^:
!(Q@1c&z
>B*zzj
~,xso0
2. 编写业务逻辑接口,并实现它(UserManager, @U1t~f^
P97i<pB Y_
UserManagerImpl) gkKNOus
java代码: BW`;QF<
U)Tl<l<
{ 9\/aXPS
/*Created on 2005-7-15*/ 2t45/:,
package com.adt.service; ^uVPN1}b^@
b.kV>K"X3
import net.sf.hibernate.HibernateException; E&U_@ bc-
ZA@zs,o%
import org.flyware.util.page.Page; lLglF4
m@0> =s~.
import com.adt.bo.Result; t=s.w(3t
ziM@@$.F
/** kmtkh"
* @author Joa Z5EII[=$o
*/ ^gR~~t;@
publicinterface UserManager { NX:\iJD)1U
{G<1.
public Result listUser(Page page)throws [qkc6sqo
(XFF}~>B.
HibernateException; }nO%q6|\V
2+g'ul`
} }jdmeD:
Cn5;h(r
r)Ml-r=
_u6MSRX[6$
)a`kL,
java代码: 6BEDk!
o&$lik
s|TO9N)pO
/*Created on 2005-7-15*/ [UB*39D7
package com.adt.service.impl; }LLQ+
'R42N3|F
import java.util.List; ua_,c\iL
"I{Lcn~!@
import net.sf.hibernate.HibernateException; *Gj`1#Z$
yF+mJ >kj
import org.flyware.util.page.Page; hFhC&2HN
import org.flyware.util.page.PageUtil; D-x*RRkpp
4p6T0II_$
import com.adt.bo.Result; M&H,`gm
import com.adt.dao.UserDAO; ocp
import com.adt.exception.ObjectNotFoundException; `G:hC5B
import com.adt.service.UserManager; t\Qm2Q)>
Vh]=sd<F
/** X gtn}7N.
* @author Joa L;+e)I]
*/ CUBL/U\=
publicclass UserManagerImpl implements UserManager { F6:LH,~8
2^:iU{
private UserDAO userDAO; If8
^
wub7w#
/** Be<bBKQb
* @param userDAO The userDAO to set. TD4
n%k.
*/ HIfi18
publicvoid setUserDAO(UserDAO userDAO){ F5M|QX@-
this.userDAO = userDAO; 9F~5Ht
} dP]Z:
K5??WB63B
/* (non-Javadoc) <DII%7q,6/
* @see com.adt.service.UserManager#listUser PGVP0H+RV
U#XW}T=|
(org.flyware.util.page.Page) :/RvtmW
*/ J{Ld)Q,^
public Result listUser(Page page)throws |W&K@g$
_.%g'=14f
HibernateException, ObjectNotFoundException { q~*|Wd'&
int totalRecords = userDAO.getUserCount(); ` 1y @c"t
if(totalRecords == 0) |It{L0=U
throw new ObjectNotFoundException !d[]Qt%mA
rhGB l`(B
("userNotExist"); #$!^1yO
page = PageUtil.createPage(page, totalRecords); ?g0dr?H
List users = userDAO.getUserByPage(page); {Hvkn{{'
returnnew Result(page, users); ]+tO
} ]@ Vp:RGMr
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} 2^U?Ztth6
Xd1+?2
~L>&p
+8GxX$
f}?pY"yvO
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 ^1aY,6I:
&W&A88FfZU
询,接下来编写UserDAO的代码: sAZL,w
3. UserDAO 和 UserDAOImpl: Qk@BM
java代码: /1= x8Sb
n^l5M^.
I+jc
/*Created on 2005-7-15*/ |O"Pb`V+
package com.adt.dao; 'gsO}xj
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import java.util.List; !thFayq
Z0wH%o\
import org.flyware.util.page.Page; T/J1 b-
oDGBC
import net.sf.hibernate.HibernateException; F:.8O ,%u
!9j6l0
/** *0r!eD
* @author Joa HPo><u
*/ /^WawH6)6
publicinterface UserDAO extends BaseDAO { |>>^Mol
D (e,R9hPU
publicList getUserByName(String name)throws XZ3M~cDq
blaXAqe
HibernateException; .Pux F
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publicint getUserCount()throws HibernateException; sp0_f;bC
`H^
H#W
publicList getUserByPage(Page page)throws b8$%=Xp
1WY$Vs
HibernateException; VwXR,(
'l-VWqR-
} ?4R q +
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jX t5.9 t
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i9peQ61{
java代码: +hlR
f.R;<V.)
>F/E,U ]
/*Created on 2005-7-15*/ hWX4 P
package com.adt.dao.impl; gDX\ p>7
>9<rc[
import java.util.List; XqcNFSo)
Jr>Nc}!U
import org.flyware.util.page.Page; ^{E_fQJX
f
uH3C~u7<
import net.sf.hibernate.HibernateException; nGTqW/k[+s
import net.sf.hibernate.Query; Fg2/rC:_
cn9=wm\\
import com.adt.dao.UserDAO; E6- ~
&G3$q,`H
/** }UG<_bE|
* @author Joa (YYwn@NGj
*/ W)Yo-%
public class UserDAOImpl extends BaseDAOHibernateImpl ItAC=/(d
w7<4D,hk
implements UserDAO { GzT?I
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160BgFM
/* (non-Javadoc) o+S?j*mv@
* @see com.adt.dao.UserDAO#getUserByName F5w=tK
=[gFaB_H
(java.lang.String) V:g XP1P
*/ c&`]O\D-c
publicList getUserByName(String name)throws F-Ku0z]){?
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Wul
HibernateException { KXu1%`x=%Z
String querySentence = "FROM user in class XhOg>
mt-t8~A
com.adt.po.User WHERE user.name=:name"; =]<X6!0mR
Query query = getSession().createQuery LM!@LQAMY
!VvM
(querySentence); `0R>r7f)H
query.setParameter("name", name); b1Ba}
return query.list(); ~BXy)IB6
} ;y>}LGG
$^#q0Yx
/* (non-Javadoc) uU+?:C
* @see com.adt.dao.UserDAO#getUserCount() !B#tJD
*/ UXHtmi|_:
publicint getUserCount()throws HibernateException { P;ZVv{mT
int count = 0; Vz y )jf
String querySentence = "SELECT count(*) FROM C{V,=Fo^
;9uDV-"
user in class com.adt.po.User"; }7qboUG e
Query query = getSession().createQuery \F7NuG:m,
W:2j.K9!
(querySentence); 1.a:iweN
count = ((Integer)query.iterate().next tA
K=W$r
:,'.b|Tl.b
()).intValue(); U
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return count; j7VaaA
} (T.g""N~`
^3Z~RK\}
/* (non-Javadoc) [?)He} _L
* @see com.adt.dao.UserDAO#getUserByPage X>MDX.Z
70nBC
(org.flyware.util.page.Page) 2j[;M-3
*/ 2(Nf$?U@0
publicList getUserByPage(Page page)throws hWr}Uui
m;u :_4
HibernateException { s 8lfW6
String querySentence = "FROM user in class h-*h;Uyc
+a'nP=e&
com.adt.po.User"; $,1KD3;+]
Query query = getSession().createQuery @8SA^u0
F=;nWQ&
(querySentence); DM{Z#b]
query.setFirstResult(page.getBeginIndex()) t
y%Hrw
.setMaxResults(page.getEveryPage()); 7t6TB*H
return query.list(); H*&!$s.
} }wGy#!CSza
ESkhCDU
} [iN\R+:
kg$w<C@#"
sg_%=;
4/&.N]
8oP"?ew#
至此,一个完整的分页程序完成。前台的只需要调用 x\5\KGw16
^=w){]G
userManager.listUser(page)即可得到一个Page对象和结果集对象 5^36nEoA(
<!~NG3KW[>
的综合体,而传入的参数page对象则可以由前台传入,如果用 &3YXDNm
rmhL|!
Y
webwork,甚至可以直接在配置文件中指定。 ZV~9{E8
d-#yN:}0
下面给出一个webwork调用示例: &t74T"(d
java代码: q&: t$tSS
!f#[4Xw
b*cVC^{Dy
/*Created on 2005-6-17*/ 6
$+b2&V
package com.adt.action.user; p@+D$
eg>]{`WQ
import java.util.List; '\Uy;,tu /
WL<f!
import org.apache.commons.logging.Log; PE2O$:b\
import org.apache.commons.logging.LogFactory; U~<~>^[
import org.flyware.util.page.Page; ^W[3RiG
Fr,b5 M<L7
import com.adt.bo.Result; Ng\]
import com.adt.service.UserService; S6c>D&Q
import com.opensymphony.xwork.Action; g|x*sZR~Y
#lx(F3
/** Pb/[945
* @author Joa PkDh[i9Z|
*/ |`@7G`x
publicclass ListUser implementsAction{
lD?]D&
UphZRgT!N
privatestaticfinal Log logger = LogFactory.getLog ":01M},RA
Yr 1k\q
(ListUser.class); ?4lEHef
bU_P@GKB
private UserService userService; S| l%JM^
gnZc`)z
private Page page; #80r?,q
A{\!nq_~N
privateList users; ||rZ+<
eu?DSad
/* s"0Hz"[^=
* (non-Javadoc) r?=3TAA
* nb U?:=P
* @see com.opensymphony.xwork.Action#execute() >2LlBLQ
*/ Trml?zexD
publicString execute()throwsException{ vOBXAF
Result result = userService.listUser(page); ^ V8?6E
page = result.getPage(); 6G?7>M
users = result.getContent(); >Gr,!yP
return SUCCESS; RVa{%
} EdS7m,d
Hr;\}
/** ~{np G
* @return Returns the page. $R/@%U)-o
*/ WD?COUEox
public Page getPage(){ 4Pr@<S"U
return page; n,%/cUl
} jg=}l1M"
wXU gxa
/** D?
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* @return Returns the users. JS0957K
*/ .Wvg{ S-
publicList getUsers(){ !v]~ut !p
return users; bODyJ7=[
} z irnur1
_qq>-{-Ym
/** L
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* @param page NPE7AdB8
* The page to set. K7]IAV
*/ lX%e
publicvoid setPage(Page page){ ,:?=j80m
this.page = page; jI,?*n<
} =1% <
1Et{lrgh
f
/** Xa/]}
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* @param users 6YYDp&nqEj
* The users to set. aUEnQ%YU"
*/ NC{8[*Kx5
publicvoid setUsers(List users){ $ D(q
this.users = users; km9@*@)
} 0*8uo
Wt&
A<[X@o}92
/** /3CdP'c
* @param userService x.aqy'/`
* The userService to set. YEhPAQNj
*/ eLN[`hJ
publicvoid setUserService(UserService userService){ E#mpj~{-
this.userService = userService; y'U-y"7y
} dmUa\1g#
} _&/2-3]\B
6eAJ>9@x
=FXq=x%9+
t{Gc,S!]5
\xexl1_;
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, _f<#+*y
55vI^SSA
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 hC...tk
,(&