Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 y"Nsh>h
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 610D%F
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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 aL\nT XakX
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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 p!s}=wI`
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分页支持类: %vBhLaE
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java代码:
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package com.javaeye.common.util; s3W@WH^.
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import java.util.List; Q
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publicclass PaginationSupport { [TNj;o5J
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publicfinalstaticint PAGESIZE = 30; 6m6zA/
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privateint pageSize = PAGESIZE; I* VCpaA
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privateList items; ^B+!N;
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privateint totalCount; - M,7N}z@;
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privateint[] indexes = newint[0]; SXt{k<|
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privateint startIndex = 0; >2By
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public PaginationSupport(List items, int j)
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totalCount){ [CAR[
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setPageSize(PAGESIZE); Q:$Zy
setTotalCount(totalCount); $ Y 7c
setItems(items); {W##^L~
setStartIndex(0); &.Zb,r$Y
}
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public PaginationSupport(List items, int DS<}@
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totalCount, int startIndex){ }W
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setPageSize(PAGESIZE); ~b:Rd{
setTotalCount(totalCount); T6~_Q}6
setItems(items); JAI)Eqqv]
setStartIndex(startIndex); aH#l9kCb
} bMU(?hb
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public PaginationSupport(List items, int 7==f\%,
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totalCount, int pageSize, int startIndex){ H)(:8~c,p
setPageSize(pageSize); x|{IwA9
setTotalCount(totalCount); mg,j:,
setItems(items); 1 `KN]Nt
setStartIndex(startIndex); w;l<[q?_
} Q3"}Hl2
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publicList getItems(){ rm}
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return items; $U/YR&vcw
} {8I. `U
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publicvoid setItems(List items){ pT$f8xJ
this.items = items; r
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} /6_|]ijc
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publicint getPageSize(){ uB7 V?A
return pageSize; E#F/88(
} *@TZ+{t
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publicvoid setPageSize(int pageSize){ t>H`X~SR?
this.pageSize = pageSize; K).n.:vYZ
} )IJQeC
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publicint getTotalCount(){ YX*Qd$chZ
return totalCount; OaL\w
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} R-P-i0~
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publicvoid setTotalCount(int totalCount){ qL94SW;
if(totalCount > 0){ kQ
this.totalCount = totalCount; Ldn8
int count = totalCount / w/L `
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pageSize; KOwOIDt
if(totalCount % pageSize > 0) pn*3\
count++; Q#EP|
indexes = newint[count]; Sv;_HZ
for(int i = 0; i < count; i++){ m%PC8bf`S
indexes = pageSize * l|hUw
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i; q=lAb\i
} vpU#xm.K
}else{ 3T&6opaF
this.totalCount = 0; ?^j^K-rx
} $u/E\l
} pZU9^Z?~6
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publicint[] getIndexes(){ V:G>G'Eh0
return indexes; CwJDmz\tk
} Ks\ NE=;5
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publicvoid setIndexes(int[] indexes){ b<]n%Q'n
this.indexes = indexes; *~/OOH$"
} 8KH\`5<
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publicint getStartIndex(){ =rR~ `
return startIndex; DvM5 k
} 98.>e
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publicvoid setStartIndex(int startIndex){ oc^Br~ Th
if(totalCount <= 0) Dk5Zh+^
this.startIndex = 0; %e@HZ"V
elseif(startIndex >= totalCount) |!F5.%PY
this.startIndex = indexes A?G^\I~v
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[indexes.length - 1]; aAy'\T$x.
elseif(startIndex < 0) |T{C,"9y
this.startIndex = 0; #Eb5: ;
else{ f>ZyI{
this.startIndex = indexes ^`<w&I@
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[startIndex / pageSize]; xTGxvGv8
} N
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} 4ikd M/
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publicint getNextIndex(){ ?3O9eZY@
int nextIndex = getStartIndex() + eznypY=
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pageSize; h!m_PgRSs
if(nextIndex >= totalCount) X=C1/4wU
return getStartIndex(); &[&r2>a
else 0 u?{\
return nextIndex; Qeu\&%C!<
} ?h!i0Rsm
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publicint getPreviousIndex(){ *|_"W+JC
int previousIndex = getStartIndex() - Z/ Tm)Xd
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pageSize; fo4.JyBk
if(previousIndex < 0) 4 QZ?}iz
return0; /\)a
else @x/T&67k
return previousIndex; phE
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} pMs
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} z]3 `*/B
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抽象业务类 Va$Pi19 O
java代码: -LM;}<
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/** ^;c 16
* Created on 2005-7-12 vzn{h)D
*/ Zatf9yGD
package com.javaeye.common.business; qT/Do?Y
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import java.io.Serializable; <|?K%FP7Z
import java.util.List; Y4IGDY*
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import org.hibernate.Criteria; Ez{MU@Fk
import org.hibernate.HibernateException; *UW=Mdt
import org.hibernate.Session; S60IPya
import org.hibernate.criterion.DetachedCriteria; pN\Vr8tJ
import org.hibernate.criterion.Projections; dSCzx
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import }oJAB1'k
MV=9!{`
org.springframework.orm.hibernate3.HibernateCallback; {_U
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import I-agZag%
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org.springframework.orm.hibernate3.support.HibernateDaoS rfw-^`&{
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upport; tDDy]==E
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import com.javaeye.common.util.PaginationSupport; -{
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public abstract class AbstractManager extends TPE:e)GO
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HibernateDaoSupport { VGqa)ri"
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privateboolean cacheQueries = false; g=T/_
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privateString queryCacheRegion; `c+/q2M
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publicvoid setCacheQueries(boolean eh R{X7J
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cacheQueries){ ~m*,mz
this.cacheQueries = cacheQueries; d1joVUYE
} #Dfo#]k(
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publicvoid setQueryCacheRegion(String gw _$
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queryCacheRegion){ _ q(Q
this.queryCacheRegion = [i]r-|_K
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queryCacheRegion; dd|W@Xp -
} xLZd!>C
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publicvoid save(finalObject entity){ 8e0."o.6
getHibernateTemplate().save(entity); s/Xb^XjS1
} htP|3 B
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publicvoid persist(finalObject entity){ w{ `|N$
getHibernateTemplate().save(entity); ^nVl (^{
}
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publicvoid update(finalObject entity){ eo^/c+FG
getHibernateTemplate().update(entity); $j)hNWI
} 2AVc?
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publicvoid delete(finalObject entity){ &Np9kIMCB
getHibernateTemplate().delete(entity); @/%{15s.
} <5@PWrU?[[
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publicObject load(finalClass entity, YwH./)r=
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finalSerializable id){ 6#A:}B<?
return getHibernateTemplate().load c-j_IN Gm
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(entity, id); X5g[ :QKP7
} p4VSma_(
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publicObject get(finalClass entity, VhEM k\
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finalSerializable id){ >NV=LOO
return getHibernateTemplate().get %~*jae!f
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(entity, id); o ojiJ~
} 5(&xNT-n8
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publicList findAll(finalClass entity){ 8cHE[I
return getHibernateTemplate().find("from Hoz5 6y
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" + entity.getName());
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} ;+pOP |P=
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publicList findByNamedQuery(finalString EP7AP4
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namedQuery){ #l1Q e`
return getHibernateTemplate (foBp
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().findByNamedQuery(namedQuery); e,A)U5X
} U l Mi.;/^
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publicList findByNamedQuery(finalString query, +?`b=6e(`
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finalObject parameter){ 8(X0
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return getHibernateTemplate \|Dei);k
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().findByNamedQuery(query, parameter); _>bRv+RVR
} yZ}d+7T}
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publicList findByNamedQuery(finalString query, ,yLw$-
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finalObject[] parameters){ #WE]`zd
return getHibernateTemplate L*?!Z^k
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().findByNamedQuery(query, parameters); `{FwTZ=6{
} Zzd/K^gg
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publicList find(finalString query){ /c+)C"
return getHibernateTemplate().find nbd Gt
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(query); %hT4qzJj
} aW5~Be$
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publicList find(finalString query, finalObject X`20f1c6q>
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parameter){ ACBQ3
return getHibernateTemplate().find 1"K*._K
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(query, parameter); _LfHs1g4
} J me%
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public PaginationSupport findPageByCriteria JE%A|R<Jl
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(final DetachedCriteria detachedCriteria){ E*v]:kok
return findPageByCriteria ^>r^3C)_-
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); L{ ^4DznI
} $T
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public PaginationSupport findPageByCriteria hH+bt!aH
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(final DetachedCriteria detachedCriteria, finalint @sf90&f
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startIndex){ m7 XjP2
return findPageByCriteria ~LE[,
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(detachedCriteria, PaginationSupport.PAGESIZE, O<,r>b,
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startIndex); a20w,
} 4'At.<]jL
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public PaginationSupport findPageByCriteria q9}2
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(final DetachedCriteria detachedCriteria, finalint dl/X."iv!
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pageSize, |"}4*V_ *
finalint startIndex){ q6[}ydV
return(PaginationSupport) P79R~m`
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getHibernateTemplate().execute(new HibernateCallback(){ kr_oUXiX
publicObject doInHibernate I($,9|9F
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(Session session)throws HibernateException { 0o68rF5^s
Criteria criteria = cgNt_8qC
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detachedCriteria.getExecutableCriteria(session); `Wf5
int totalCount = rye)qp|
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((Integer) criteria.setProjection(Projections.rowCount FP;":i RL
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()).uniqueResult()).intValue(); F_PTMl=Q|J
criteria.setProjection @P70W<<
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(null); A
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List items = Gc5VQ^]
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criteria.setFirstResult(startIndex).setMaxResults 0(TvQ{
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(pageSize).list(); 2NR7V*A
PaginationSupport ps = =K6c;
ta! V=U
new PaginationSupport(items, totalCount, pageSize, <P pYl
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startIndex); y"R("j $
return ps; ?cBO6^
} Q eK{MF
}, true); T 'i~_R6
} o4'v> b
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public List findAllByCriteria(final &l!$Sw-u;
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DetachedCriteria detachedCriteria){ 6<76O~hNZ
return(List) getHibernateTemplate 0o;~~\fq.
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().execute(new HibernateCallback(){ =5_y<0`4
publicObject doInHibernate #O6
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(Session session)throws HibernateException { C@)pmSQ
Criteria criteria = rys<-i(
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detachedCriteria.getExecutableCriteria(session); 3jg'1^c
return criteria.list(); y1Z1=U*!
} 8}K"IW
}, true); qp1\I$Y
} 4f
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public int getCountByCriteria(final Z%;)@0~f
) BlJ|M
DetachedCriteria detachedCriteria){ zkG>u,B}
Integer count = (Integer) 3*2I$e!Jt
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getHibernateTemplate().execute(new HibernateCallback(){ n>T:2PQ3
publicObject doInHibernate [edH%S}\
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(Session session)throws HibernateException { M4H"].Zm
Criteria criteria = i?W]*V~ply
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detachedCriteria.getExecutableCriteria(session); ~%KM3Vap
return 9RB`$5F;
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criteria.setProjection(Projections.rowCount -4%]QS
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()).uniqueResult(); O$(c.(_$
} #'c%
}, true); v<+4BjV!J}
return count.intValue(); _2; ^v`[
} $*i7?S@~-
} pzAoq)gg:
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用户在web层构造查询条件detachedCriteria,和可选的 7
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 uNg'h/^NZ|
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PaginationSupport的实例ps。 ])S$x{.g
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ps.getItems()得到已分页好的结果集 k~R{Y~W!!
ps.getIndexes()得到分页索引的数组 'hy?jQ'|e
ps.getTotalCount()得到总结果数 $59nu7yr
ps.getStartIndex()当前分页索引 a0{[P$$
ps.getNextIndex()下一页索引 v*vn<nPAQ>
ps.getPreviousIndex()上一页索引 p}&Md-$1
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 7}A5u,.,ht
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,尤其是上面的示例代码,让我着实觉得该对我原来的分页查询做 Pu-p7:99;'
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一下代码重构了。 KS?mw`Nr
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我把原本我的做法也提供出来供大家讨论吧: l:q8Pg)
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首先,为了实现分页查询,我封装了一个Page类: CJv>/#$/F
java代码: xM%`KP.8X
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/*Created on 2005-4-14*/ %N>\:85?
package org.flyware.util.page; A3z/Bz4]:#
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/** )`mbf|,&t{
* @author Joa 3;y_qwA
* Ri;=aZ5m
*/ l 4!kxXf-<
publicclass Page { [7'#~[a~
@81-kdTx
/** imply if the page has previous page */ (1rJFl!
privateboolean hasPrePage; TF%3uH
{x7=;-
/** imply if the page has next page */ qw5&Y$((
privateboolean hasNextPage; W=UqX{-j)
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/** the number of every page */ VccM=w%*
privateint everyPage; 6g}^Q?cpV#
&{ DR6
/** the total page number */ 1;aF5~&
privateint totalPage; ;i.I&*t
*}>Bkq9h
/** the number of current page */ *X~B-a |nJ
privateint currentPage; ) @!~8<_"
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/** the begin index of the records by the current u1tq2"D8
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query */ ,.[.SU#V
privateint beginIndex; P`p6J8}4
vc )9Re$
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/** The default constructor */ G4O,^ v;Q
public Page(){ `'*F1F
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} D!X>O}
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/** construct the page by everyPage $4DFgvy$
* @param everyPage Vu_&~z7h
* */ Z"-ntx#
public Page(int everyPage){ "|F.'qZrm
this.everyPage = everyPage; xy$vYDAFw
} ]}p2Tp;1
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/** The whole constructor */ %I_&Ehu
public Page(boolean hasPrePage, boolean hasNextPage, 1po"gVot
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int everyPage, int totalPage, -E6J f$
int currentPage, int beginIndex){ j \!~9
this.hasPrePage = hasPrePage; Y_$^:LG
this.hasNextPage = hasNextPage; =
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this.everyPage = everyPage; &1*4%N@'
this.totalPage = totalPage; be&6kG
this.currentPage = currentPage; h0T< :X
this.beginIndex = beginIndex; c =jcvDQ6W
} NR;q`Xe-
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/** 2_Pz^L
* @return ^a086n
* Returns the beginIndex. N
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*/ BHF{-z
publicint getBeginIndex(){ 2^cAK t6bC
return beginIndex; W8Ke1(ws&
} ^?E^']H)5u
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/** `kqT{fs
* @param beginIndex d|>9rX+f
* The beginIndex to set. c zZrP"
*/ I h5/=_n
publicvoid setBeginIndex(int beginIndex){ $|>6z_3%
this.beginIndex = beginIndex; ny278tr Q7
} nwY2BIB
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/** JCM)N8~i
* @return UN,<6D3\b
* Returns the currentPage. -;sJ25(
*/ aw%>YrJ
publicint getCurrentPage(){ "CIpo/ebL
return currentPage; `DI{wqV9
} <FXQxM5"
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/** 6>@(/mh*
* @param currentPage J% :WLQo
* The currentPage to set. Z|]l"W*w
*/ UeMnc 5y
publicvoid setCurrentPage(int currentPage){ $.ymby
this.currentPage = currentPage; w;lx:j!Vp$
} vs5
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/** 6$W -?
* @return &i4
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* Returns the everyPage. fGu5%T,
*/ ;e&hM\p
publicint getEveryPage(){ o@qN#Mg?>}
return everyPage; F@>w&A~K
} =_#ye}E
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/** ZrmnQ
* @param everyPage )v*v
* The everyPage to set. Ln"+nKr
*/ K?z*3^^X;
publicvoid setEveryPage(int everyPage){ u+%)JhIp
this.everyPage = everyPage; B ]|5?QP-
} ;y:#S^|?-z
d/0/$Bz}P
/** X !&"&n
* @return b|X>3(
* Returns the hasNextPage. y}(_SU
*/ X;K8,A7`
publicboolean getHasNextPage(){ e1f^:C
return hasNextPage; N&R
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} Ig40#pA
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/** ,U|u-.~ZU
* @param hasNextPage ]=$-B
* The hasNextPage to set. x]yHBc
*/ ')5jllxv
publicvoid setHasNextPage(boolean hasNextPage){ iqU.a/~y
this.hasNextPage = hasNextPage; !nP8ysB
} cHqvkN`
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/** o=a:L^nt,
* @return htdn$kqG
* Returns the hasPrePage. ~NNaLl
*/ ZaEBdBv
publicboolean getHasPrePage(){ 9m<X-B&P
return hasPrePage;
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} t[H _6)
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/** EvGU j$
* @param hasPrePage 'W<a54T?z
* The hasPrePage to set. 1CF7
*/ 44/0}v]
publicvoid setHasPrePage(boolean hasPrePage){ 0C9QAJa
this.hasPrePage = hasPrePage;
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} U 8qKD
uK"$=v6|
/** l(0&6ENyj
* @return Returns the totalPage. ;X9MA=b
* xX/Qoq (}i
*/ 1*c0\:BQ;z
publicint getTotalPage(){ TkoCyD9
return totalPage; % @^VrhS
} rRA_'t;uK
2WbZ>^:Nsk
/** `9G$p|6
* @param totalPage AW{/k'%xw
* The totalPage to set. 1*x5/b
*/ @BB,i /
publicvoid setTotalPage(int totalPage){ CwCo"%E8}
this.totalPage = totalPage; Bv
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} sKE*AGFLd
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} \8C*O{w
egIS rmL+X
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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 lHj7O&+
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个PageUtil,负责对Page对象进行构造: J^<j=a|D
java代码: ;4O;74`Zh
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/*Created on 2005-4-14*/ #L+s%OJ`
package org.flyware.util.page; WLj_Zo*^x
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import org.apache.commons.logging.Log; LeRh(a`=$
import org.apache.commons.logging.LogFactory; JOE{&^j
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/** .q;RNCUt
* @author Joa D$^7Xhk
* XTn{1[.O
*/ ?M1 QJ
publicclass PageUtil { ]cO$ E=W
~9{-I{=
privatestaticfinal Log logger = LogFactory.getLog 2Dwt4V
@v:ILby4-
(PageUtil.class); >f9]Nj
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/** wxr}*Z:ZMa
* Use the origin page to create a new page qLktMp_
* @param page ph$&f0A6Xc
* @param totalRecords (x*2BEn|
* @return 1>O0Iu
*/ rj`.hXO
publicstatic Page createPage(Page page, int uJAB)ti2I
v:;C|uE|
totalRecords){ 9#=IrlV4
return createPage(page.getEveryPage(), 5x L,~"
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page.getCurrentPage(), totalRecords); neMe<jr
} -<VF6k<
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/** 66y ,{t
* the basic page utils not including exception f~(^|~ZT
!nD[hI8P
handler oCru 5F
* @param everyPage $@
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* @param currentPage (^OC%pc
* @param totalRecords 6T'43h. :
* @return page MrygEC 5
*/ p44uozbK
publicstatic Page createPage(int everyPage, int c=c.p
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currentPage, int totalRecords){ oz5lt4
everyPage = getEveryPage(everyPage); !*QA;*e
currentPage = getCurrentPage(currentPage); C&MqUj"]
int beginIndex = getBeginIndex(everyPage, $EHn;~w T
Ns7l-mb
currentPage); J,2v~Dq
int totalPage = getTotalPage(everyPage, ',-X#u
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totalRecords); :\HN?_?{4
boolean hasNextPage = hasNextPage(currentPage, fJ+E46|4
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totalPage); N7|W.(
boolean hasPrePage = hasPrePage(currentPage); MyR\_)P?
7Bb@9M?i
returnnew Page(hasPrePage, hasNextPage, 7}HA_@[
everyPage, totalPage, ,2L,>?r6
currentPage, tYxlM!
qb/!;U_
beginIndex); Y&:\s8C
} K Qy\l+\gM
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privatestaticint getEveryPage(int everyPage){ #T#FUI1p
return everyPage == 0 ? 10 : everyPage; ynz5Dy.d;
} ;]ZHD$g
bsS|!KT
privatestaticint getCurrentPage(int currentPage){ E52:c]<'m
return currentPage == 0 ? 1 : currentPage; 6/[h24d
} er}'}n`@q
P_}_D{G
privatestaticint getBeginIndex(int everyPage, int k/f_@8
m>m`aLrnb
currentPage){ +GEKg~/4e
return(currentPage - 1) * everyPage; :<|fZa4!"
} Wh&Z *J
J'oz P^N
privatestaticint getTotalPage(int everyPage, int I,q~*d
Gl\RAmdc
totalRecords){ 3uiitjA]
int totalPage = 0; 7PPsEU:rf
6I'VXdeN
if(totalRecords % everyPage == 0) @n y{.s+
totalPage = totalRecords / everyPage; +hYmL
Sq
else '3,JL!
totalPage = totalRecords / everyPage + 1 ; -cS4B//IK8
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return totalPage; "e?#c<p7
} lIT2 AFX+
p~y
4q4
privatestaticboolean hasPrePage(int currentPage){ yOm6HA``hT
return currentPage == 1 ? false : true; k$mX81
} [&59n,R`
vTa23YDW
privatestaticboolean hasNextPage(int currentPage, ]-]@=qYu
206jeH9
int totalPage){ _34YH 5
return currentPage == totalPage || totalPage == #k]0[;1os
S 2` ;7
0 ? false : true; Y{B_OoTun
} l`G:@}P>G
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;:YjgZ:+Q]
} YXOD
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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。 jWjK -q@Y
}|,\?7,
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 KPK!'4,cu
3om7LqcRo
做法如下: U-:Z^+Y
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 YS6az0ie
MA QY/s~F
的信息,和一个结果集List: 2]KPW*V
java代码: :D7!6}%
DO*C]
Icb;Yzt
/*Created on 2005-6-13*/ v2<gkCK^
package com.adt.bo; nmAXU!t'
^OsUWhkV
import java.util.List; M0\[hps~X
S5p\J!k\B
import org.flyware.util.page.Page; =hb87g.
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/** %zVv3p:
* @author Joa y9mZQq
*/ agot
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publicclass Result { -igZU>0B_
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private Page page; `{[C4]Ew/
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private List content; 6<O]_ HZ&
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q
/**
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* The default constructor vCr$miZ
*/ *38\&"s4_
public Result(){ ;\0RXirk
super(); IKj1{nZvDc
} `2+52q<FO
'KrkCA
/** cMKh+r
* The constructor using fields }z:=b8}
* 1EzA@3:{
* @param page M#,+p8
* @param content {[iQRYD0|
*/ @K>Pw arl
public Result(Page page, List content){ ioQlC4Y
this.page = page; G*V
7*KC
this.content = content; NsK >UJ'
} nr6U>
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/** !9Ni[8&Fg0
* @return Returns the content. @1X1E 2:
*/ [#H8Mb+7
publicList getContent(){ D]y.!D{l2
return content; 9a,CiH%@
} [X\2U4
b&&'b)
/** w%na n=
* @return Returns the page. cE?J]5#^
*/ Tl-B[CT
public Page getPage(){ cViCWc2
return page; ;pYk+r6 Cr
} qN(;l&Q
G(e?]{(
/** g_=ZcGC
* @param content <Z_`^~!
* The content to set. xJlq2cK
*/ '!GI:U+g
public void setContent(List content){ [Y+bW#'
this.content = content; eGg#=l=
} 1Tkz!
@[lr
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/** 1k(*o.6
* @param page m\Nc}P_"p
* The page to set. =uEhxsj)S
*/ M3;B]iRQD
publicvoid setPage(Page page){ =@ RVLml
this.page = page; 6UTdy1Qq>
} s4*,ocyBP
} ^\;5O(9
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tc Z~T
ggWfk
dDn:^)
2. 编写业务逻辑接口,并实现它(UserManager, 4G2V{(@QiZ
cgAcAcmY
UserManagerImpl) ?U[AE -*
java代码: W@Wh@eSb;
X8TZePh
[)?3Dp|MH
/*Created on 2005-7-15*/ G@2M&0'
package com.adt.service; 1:8: yFV
9IMcp~zX
import net.sf.hibernate.HibernateException; e)8iPu ..
)kUw,F=6
import org.flyware.util.page.Page; =lnz5H
wXnt3)e
import com.adt.bo.Result; 8B5%IgA
J!>oC_0]8
/** !h~\YE)
* @author Joa {,ljIhc,
*/ XhiC'.B_
publicinterface UserManager { {DR+sE
3lqhjA
public Result listUser(Page page)throws X"sN~Q.0
~gD'up@$/
HibernateException; V8/o@I{U[
nEYJ?_55
} bC|~N0b
z m%\L/BF
t+tGN\q
OZD/t(4?6s
pOXEM1"2A
java代码: W*2SlS7
' wEP:}
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/*Created on 2005-7-15*/ wl4yNC
package com.adt.service.impl; S/|8'x{<
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Sf
import java.util.List; D3OV.G]`
@\a- =
import net.sf.hibernate.HibernateException; idq= US
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import org.flyware.util.page.Page; }Z|a?J@CZm
import org.flyware.util.page.PageUtil;
slbV[xR
~F-,Q_|-
import com.adt.bo.Result; >JhQ=j
import com.adt.dao.UserDAO; 6{6tg>|L)
import com.adt.exception.ObjectNotFoundException; - U|4`{PP
import com.adt.service.UserManager; s]qfLC
FpEdwzBb<
/** ur|2FS7
* @author Joa +q;^8d>
*/ r BL)ct
publicclass UserManagerImpl implements UserManager { _cB~?c
/[p4. FL
private UserDAO userDAO; ?w+T_EH
u|C9[(
/** f]EHDcC3X
* @param userDAO The userDAO to set. sQkP@Y
*/ !Kis,e
publicvoid setUserDAO(UserDAO userDAO){ NTC,Vr\A
this.userDAO = userDAO; S/4kfsN
} !PgYn
oUqNA|l
T
/* (non-Javadoc) k`d
* @see com.adt.service.UserManager#listUser Wd7*sa3T
)-mB^7uXGv
(org.flyware.util.page.Page) 8dv1#F|
*/ 1/ a,7Hl
public Result listUser(Page page)throws *QLbrR
q^s$4 q
HibernateException, ObjectNotFoundException { Ugn"w E
int totalRecords = userDAO.getUserCount(); rr*IIG&.5
if(totalRecords == 0) E4{8 $:q=
throw new ObjectNotFoundException \,WPFV
GM5::M]fS
("userNotExist"); GZ1>]HB>r^
page = PageUtil.createPage(page, totalRecords); ci!c7 ,'c
List users = userDAO.getUserByPage(page); <D__17W:;
returnnew Result(page, users); 1~+w7Ar=(
} 5)vXmAD/0
l"+=z.l6;
} ReY K5J=O
+$%o#~
8ViDh
~HELMS~-
qnOAIP:0
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 \oi=fu=}*
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询,接下来编写UserDAO的代码: @c/~qP4
3. UserDAO 和 UserDAOImpl: pCq{F*;
java代码: <v\|@@X
Mqq7;w@(J
OlP#|x*
/*Created on 2005-7-15*/ }}
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package com.adt.dao; Nz m
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mGIS[_dcs
import java.util.List; G B15
j9Lc2'
import org.flyware.util.page.Page; n7S[ F3
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import net.sf.hibernate.HibernateException; $I_aHhKt
0j*8|{|
/** WPPmh~:
* @author Joa xHf
l>C'
*/ noacnQ_I$
publicinterface UserDAO extends BaseDAO { YcIk{_N3
/t816,i
publicList getUserByName(String name)throws t({:TQ
nF)|oA
HibernateException; v8LKv`I's
)0NA*<Q+.
publicint getUserCount()throws HibernateException; us/x.qPy2
n04Zji(F@
publicList getUserByPage(Page page)throws 7y:J@fh<
5[0n'uH
HibernateException; wL:3RZB
8^O|Aa$IF:
} 4YKb~1qkk
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GSypdEBj+w
$Q62
7
Mq$e5&/
java代码: BsxQW`>^y
f;QWlh"9
NbSwn}e_
/*Created on 2005-7-15*/ =x=#Etj|
package com.adt.dao.impl; |S/nq_g]
=l
{>-`:
import java.util.List; LdA&F&
pI
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import org.flyware.util.page.Page; Ra.<D.
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import net.sf.hibernate.HibernateException; aaLT%
import net.sf.hibernate.Query; IXg0g<JZ
@@+\
import com.adt.dao.UserDAO; y6$5meh.T
"S1+mSW>
/** ibEQ5 2
* @author Joa q")}vN
*/ }E*#VA0/nY
public class UserDAOImpl extends BaseDAOHibernateImpl wL~
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GQq2;%RrF
implements UserDAO { lE /"
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/* (non-Javadoc) h T4fKc7P
* @see com.adt.dao.UserDAO#getUserByName u" nyx0<
tlc&Wx
(java.lang.String) !tN]OQ)'
*/ |XPT2eQ{
publicList getUserByName(String name)throws QH;1*
;|66AIwDe
HibernateException { 68d(6?OgW
String querySentence = "FROM user in class :h" Y >1P
`*N2x\+X
com.adt.po.User WHERE user.name=:name"; lr=*Ty(V
Query query = getSession().createQuery Z>'.+OW
wuI+$?
(querySentence); e:&5Cvx
query.setParameter("name", name); {=pf#E=
return query.list(); {~ VgXkjsC
} >!?u8^C
+tl&Jjdm
/* (non-Javadoc) c/b}39X
* @see com.adt.dao.UserDAO#getUserCount() BJ1txdxvS
*/ ^,@Rd\q
publicint getUserCount()throws HibernateException { AS~O*(po
int count = 0; H+ t^eg88
String querySentence = "SELECT count(*) FROM "|(+~8[
n hS=t8H
user in class com.adt.po.User"; |K7JU^"OQ
Query query = getSession().createQuery <Xv]Ih?@f`
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d?
(querySentence); `G,\=c~{A
count = ((Integer)query.iterate().next y~jTI[kS
L=?Yc*vg
()).intValue(); 5)nm6sf
return count; 1:XT r
} $yBU
,lu}
Mvu!
/* (non-Javadoc) :(N3s9:vz
* @see com.adt.dao.UserDAO#getUserByPage M{Wla7
Od)]FvO
(org.flyware.util.page.Page) )Yy`$`
*/ ohOze\T)=
publicList getUserByPage(Page page)throws Kb#py6
Syo1Dq6z.
HibernateException { Bzw~OB{!=J
String querySentence = "FROM user in class xbSix:R=Z
5e6 f)[}
com.adt.po.User"; skf7Si0z
Query query = getSession().createQuery &dH/V-te
%TP0i#J
(querySentence); <T,vIXwu+
query.setFirstResult(page.getBeginIndex()) kO+Y5z6=
.setMaxResults(page.getEveryPage()); 8 W79
return query.list(); zvL;.U
} MZv In ZS
h:}oUr8
} vg5i+ry<
@/g%l1$`
`,3;#.[D
H_un3x1
B~G?&"]
至此,一个完整的分页程序完成。前台的只需要调用 KQ9~\No]
W c{<DE?J
userManager.listUser(page)即可得到一个Page对象和结果集对象 )k&<D*5s
\GO^2&g(
的综合体,而传入的参数page对象则可以由前台传入,如果用 S=*rWh8)%<
g:7S/L0]
webwork,甚至可以直接在配置文件中指定。 <-D>^p9
OTY9Q
下面给出一个webwork调用示例: z1{kZk
java代码: xrs?"]M[
:<r.n
"
IQAV`~_G
/*Created on 2005-6-17*/ ;`p+Vs8C
package com.adt.action.user; 5B<