Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 >i5acuth
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 G|(
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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 -lhLA`6_R
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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 BbgnqzU
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。 }RwSp!}C
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分页支持类: 3>R#zJf
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java代码: ~Uxsn@nLr
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package com.javaeye.common.util; =
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import java.util.List; UmQ?rS8d
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publicclass PaginationSupport { t=-SH^$SR
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publicfinalstaticint PAGESIZE = 30; ^sVX)%
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privateint pageSize = PAGESIZE; Er+nk`UR_
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privateList items; A9kzq_3
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privateint totalCount; #1c_ev H
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privateint[] indexes = newint[0]; DM}YJ
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privateint startIndex = 0; /ig:9R
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public PaginationSupport(List items, int dO4{|(z
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totalCount){ jSwf*u
setPageSize(PAGESIZE); \o/n
setTotalCount(totalCount); uU:CR>=AKW
setItems(items); <oo
setStartIndex(0); '*?WU_L(g
} -*m+(7G\
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public PaginationSupport(List items, int kn>$lTHQ
8`fjF/
totalCount, int startIndex){ $`-4Ax4%
setPageSize(PAGESIZE); =Q[b'*o7
setTotalCount(totalCount); Nqrmp" ]
setItems(items); 1f8GW
setStartIndex(startIndex); hWT[L.>k
} ^1L>l9F
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public PaginationSupport(List items, int |"9 #bU
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8
totalCount, int pageSize, int startIndex){ ! ykx^z
setPageSize(pageSize); 9$|Gfyv
setTotalCount(totalCount); ]- 4QNc=
setItems(items);
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setStartIndex(startIndex); *0>mB
} .?!N^_ Ez3
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publicList getItems(){ ^pe{b9c
return items; +{L<? "
} YBP:q2H
K!] 1oy'V
publicvoid setItems(List items){ ]sGHG^I6
this.items = items; K%X^n>O7C
} D*YM[sN`
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publicint getPageSize(){ =n'
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return pageSize; ^-[ ?#]
} gW1b~(
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publicvoid setPageSize(int pageSize){ [_.5RPJP8
this.pageSize = pageSize; mUz\ra;z
} 6^c>,.R
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publicint getTotalCount(){ i6 (a@KRY
return totalCount; ZU9c 5/J
} OKvPL=~
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publicvoid setTotalCount(int totalCount){ f}@jFhr'<
if(totalCount > 0){ (<Th=Fns?
this.totalCount = totalCount; =pk)3<GwF
int count = totalCount / <@Fy5k-%.
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pageSize; L
if(totalCount % pageSize > 0) ~2zMkVH
count++; 0sh/|`\
indexes = newint[count]; zWb4([P;
for(int i = 0; i < count; i++){ Xj5~%DZp
indexes = pageSize * XFh>U7z.
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i; Z KOXI%~Mc
} {vN}<f`
}else{ YNBHBK4;
this.totalCount = 0; ,s_T pq
} OHflIeq#@
} $Tb G+Eb8
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publicint[] getIndexes(){ C>[fB|^
return indexes; D^-7JbE]
} Kmdlf,[3d
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publicvoid setIndexes(int[] indexes){ cn-
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this.indexes = indexes; (
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} =Mb1o[
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publicint getStartIndex(){ s9>(Jzcf9
return startIndex; 2*w:tT8+X
} ]l(wg]
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publicvoid setStartIndex(int startIndex){ mnID3=JF
if(totalCount <= 0) Y2[A2Uy$ef
this.startIndex = 0; ZDC9oX @
elseif(startIndex >= totalCount) bI y sl
this.startIndex = indexes >R2SQA o
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[indexes.length - 1]; wfP5@ !I
elseif(startIndex < 0) "sKa`WN}
this.startIndex = 0; u^j {U}
else{ MCP "GZK6W
this.startIndex = indexes `W-&0|%Ta
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[startIndex / pageSize]; PD LpNTBf
} {h KjD"?
} ?9X&tK)E-
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publicint getNextIndex(){ LjH*rjS4
int nextIndex = getStartIndex() + i"j(b|?e
pW]4bx@E
pageSize; gXH[$guf
if(nextIndex >= totalCount) kGUJ9Du
return getStartIndex(); vw)7 !/#
else u?[ q=0.J7
return nextIndex; Zv_jy@k
} C P3<1~
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publicint getPreviousIndex(){ :v L1}H<
int previousIndex = getStartIndex() - 1H,g=Y4f%
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pageSize; 8v)_6p(<x8
if(previousIndex < 0) EOoZoVdzx
return0; O`$#Pg
else zj|/ CxV
return previousIndex; 3<?XTv-
} G8I Y#
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} oQ7]=|
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抽象业务类 &VBd~4|p
java代码: f2,1<^{
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/** o_Si mJFK
* Created on 2005-7-12 ?K@t0a
*/ I=Oy-
package com.javaeye.common.business; poJg"R4
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import java.io.Serializable; ]p~IYNl2%j
import java.util.List; 0~ &"
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import org.hibernate.Criteria; Se!)n;?7Sw
import org.hibernate.HibernateException; Fn^C{p^
import org.hibernate.Session; GyC /_ntn
import org.hibernate.criterion.DetachedCriteria; 1|?K\B
import org.hibernate.criterion.Projections; w^1Fi8+
import R1-k3;v^
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org.springframework.orm.hibernate3.HibernateCallback; QI_59f>
import ]/T-t1D
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org.springframework.orm.hibernate3.support.HibernateDaoS SLhEc
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upport; B/"2.,
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import com.javaeye.common.util.PaginationSupport; lr2rQo>
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public abstract class AbstractManager extends +3,|"g::
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HibernateDaoSupport { WjMS5^ _
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privateboolean cacheQueries = false; 2BzqY`O
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privateString queryCacheRegion; eu'1H@vX(
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publicvoid setCacheQueries(boolean #ycL'T`X%
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cacheQueries){ Z v0C@r
this.cacheQueries = cacheQueries; ~@8+hnE]
} =ex'22
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publicvoid setQueryCacheRegion(String +dkS/b
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queryCacheRegion){ !6w{(Rc(C
this.queryCacheRegion = 0W>9'Rw
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queryCacheRegion; iS@\ =CK
} |)W!jC&k
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publicvoid save(finalObject entity){ ;TZGC).6
getHibernateTemplate().save(entity); `dJDucD
} V)D-pV V
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publicvoid persist(finalObject entity){ ,f:
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getHibernateTemplate().save(entity); ]#<
} s>z2 k
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publicvoid update(finalObject entity){ _eLVBG35z
getHibernateTemplate().update(entity); HBLWOQab
} F?Or;p5`Y
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publicvoid delete(finalObject entity){ sXl ??UGe
getHibernateTemplate().delete(entity); 'nK~'PZ,
} PdY>#Cyh
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publicObject load(finalClass entity, +zWrLf_Rc
@XOi62(
finalSerializable id){ G+)?^QTn
return getHibernateTemplate().load YDiN^q7
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(entity, id); FQf#*
} Xy#VQ{!
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publicObject get(finalClass entity, N_C_O$j
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finalSerializable id){ H?}wl%
return getHibernateTemplate().get -Gsl[Rc0H;
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(entity, id); h'^FrWaU/
} >,h1N$A+
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publicList findAll(finalClass entity){ QJ];L7Hbo
return getHibernateTemplate().find("from # bX~=`
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" + entity.getName()); gwQvao
} ma}}Sn)Q
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publicList findByNamedQuery(finalString ~HP
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namedQuery){ ;.Zh,cU
return getHibernateTemplate N4 [E~-
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().findByNamedQuery(namedQuery); R'EW7}&
} U($^E}I2(
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publicList findByNamedQuery(finalString query, ,0T)Oc|HL/
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finalObject parameter){ xQz#i-v
return getHibernateTemplate ^now}u9S6
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().findByNamedQuery(query, parameter); GqjO>v fy
} "d?f:x3v^
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publicList findByNamedQuery(finalString query, `=!p$hg($
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finalObject[] parameters){ PN\V[#nS
return getHibernateTemplate Pi%tsKk%
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().findByNamedQuery(query, parameters); u~71l)LA
} 'P/taEi=R
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publicList find(finalString query){ spiDm:Xe
return getHibernateTemplate().find P$h;SK
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(query); 0^>E`/
} v:P!(`sF
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publicList find(finalString query, finalObject ;a{rWz1Wm
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parameter){ DN|vz}s
return getHibernateTemplate().find -IvL+}K
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(query, parameter); eH=c|m]!P
} -q(:%;
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public PaginationSupport findPageByCriteria _z:Qhe
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(final DetachedCriteria detachedCriteria){ Ak|b0l>^
return findPageByCriteria ew"m!F#
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); 6ZHv,e`?
} |Y4q+sDW
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public PaginationSupport findPageByCriteria x=3I)}J(kn
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(final DetachedCriteria detachedCriteria, finalint ]xB6cPdLu
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startIndex){ rHo6iJj
return findPageByCriteria I:/4t^%
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(detachedCriteria, PaginationSupport.PAGESIZE, i -V0Lm/
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startIndex); tD^a5qPh
} ^HoJ.oC/
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public PaginationSupport findPageByCriteria gDc]^K4>
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(final DetachedCriteria detachedCriteria, finalint (lWKy9eTy`
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pageSize, h~.V[o7=
finalint startIndex){ #[(0tc/
return(PaginationSupport) #J3zTG(:@
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getHibernateTemplate().execute(new HibernateCallback(){ eb7UoZw
publicObject doInHibernate _pW'n=}R
@_uFX!;
(Session session)throws HibernateException { }Y$VB%&Hy
Criteria criteria = W#Cq6N
}amE6
detachedCriteria.getExecutableCriteria(session); *hl<Y,W(
int totalCount = =KW|#]RB^
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((Integer) criteria.setProjection(Projections.rowCount tpz=}q
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()).uniqueResult()).intValue(); [sptU3,2U
criteria.setProjection :`j"Sj!t3
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(null); YL!oF^XO
List items = *q[^Q'jnN
1[#
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criteria.setFirstResult(startIndex).setMaxResults tdb4?^.s
95% :AQLV
(pageSize).list(); `v<f}
PaginationSupport ps = 3V!W@[ }:
@hBx,`H^
new PaginationSupport(items, totalCount, pageSize, \ /sF:~=
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startIndex); 5\5~L
return ps; o+R. u}|
} 1dXh\r_n
}, true); .>a$g7Rj
} C!I\Gh
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public List findAllByCriteria(final <|wmjW/D
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DetachedCriteria detachedCriteria){ ),z,LU Yf
return(List) getHibernateTemplate 8*"rZh}'
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().execute(new HibernateCallback(){ rufRaar
publicObject doInHibernate 8Q+TE;
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(Session session)throws HibernateException { 'fXer!L}
Criteria criteria = F}\[eFf[
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detachedCriteria.getExecutableCriteria(session); jeyaT^F(
return criteria.list(); )
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} 8g&uE*7N
}, true); KS8\F0q
} _GRv
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public int getCountByCriteria(final wP+'04H0
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DetachedCriteria detachedCriteria){ >E{#HPpBi
Integer count = (Integer) "F04c|oR<X
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getHibernateTemplate().execute(new HibernateCallback(){ Pm'.,?"
publicObject doInHibernate sCuQB Z h
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(Session session)throws HibernateException { \"{/yjO|4
Criteria criteria = aj%
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detachedCriteria.getExecutableCriteria(session); %Tk}s fx
return I*%&)Hj~
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criteria.setProjection(Projections.rowCount (}~ 1{C@
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()).uniqueResult(); #{.pQi})
} =#J9
}, true); Q2??Kp]1
return count.intValue(); <$Xn:B<H
} i,\t]EJAU
} >!CH7wX
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用户在web层构造查询条件detachedCriteria,和可选的 }d$vcEI$3
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 $=QNGC2+
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PaginationSupport的实例ps。
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ps.getItems()得到已分页好的结果集 B]CS2LEqh
ps.getIndexes()得到分页索引的数组 o%QhV6(F
ps.getTotalCount()得到总结果数 ,5%aP%
ps.getStartIndex()当前分页索引 V1AEjh
ps.getNextIndex()下一页索引 4{1c7g
ps.getPreviousIndex()上一页索引 GZ-n!
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 AF07KA#
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,尤其是上面的示例代码,让我着实觉得该对我原来的分页查询做 t~udfOvY
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一下代码重构了。 qugPs(uQ
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我把原本我的做法也提供出来供大家讨论吧: @vDgpb@TM
1-ndJ@Wlz
首先,为了实现分页查询,我封装了一个Page类: c9/
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java代码: =[O<.'aG-
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/*Created on 2005-4-14*/ Ynt&cdK9
package org.flyware.util.page; +$an*k9
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/** '8((;N|I^
* @author Joa }*{\)7g
* UeC%Wa<[
*/ +5seT}h
publicclass Page { MWp\D#H
*U5>j#,
/** imply if the page has previous page */ p3'mJ3MA
privateboolean hasPrePage; \3@2rW"5
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/** imply if the page has next page */ N1B$ G
privateboolean hasNextPage; EUYa =-
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/** the number of every page */ 3IRRFIiO
privateint everyPage; cC(ubUR
B "s8i{Vm
/** the total page number */ @[Jt~v
privateint totalPage; u"CIPc{Sr
4YB7og%P
/** the number of current page */ 2TevdyI
privateint currentPage; Cvu8X&y
U3dR[*
/** the begin index of the records by the current ^FyvaO
(J?}eb;>n
query */ OD2ai]!v+
privateint beginIndex; :pV("tHE
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/** The default constructor */ |4 d{X@`&
public Page(){ Ozh^Q$>u
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} #uDBF
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/** construct the page by everyPage FZ'>LZ
* @param everyPage PY3Vu]zD
* */ \c@qtIc
public Page(int everyPage){ cq+M
*1;
this.everyPage = everyPage; BIB>U W
} o^"d2=
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/** The whole constructor */ ~QQ23k&
public Page(boolean hasPrePage, boolean hasNextPage, 1rzq$, O
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int everyPage, int totalPage, \gk3w,B?E
int currentPage, int beginIndex){ )v$Cv|"
this.hasPrePage = hasPrePage; h"Yqm"U/
this.hasNextPage = hasNextPage; >+c`GpZH
this.everyPage = everyPage; "x) pp
this.totalPage = totalPage; ,Elga}7u
this.currentPage = currentPage; (nP*
this.beginIndex = beginIndex; J\8l%4q3
} s }R:q
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/** U"R.!=v
* @return RAkFgC~
* Returns the beginIndex. k:uuJ|
*/ TB3T:A>2
publicint getBeginIndex(){ 9j>sRE1
return beginIndex; )9W#5V$
} HjY-b*B
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/** 3U.B[7fOM
* @param beginIndex b42pLbpe'E
* The beginIndex to set. ,IvnNnl2
*/ YKS'#F2
publicvoid setBeginIndex(int beginIndex){ $Q7E#
this.beginIndex = beginIndex; E*b[.vUp
} D;8V{Hs
;[\2/$-
/** nQYS{`hk
* @return %TggNU,
* Returns the currentPage. Ph_m'fbf
*/ 9)hC,)5
publicint getCurrentPage(){ g]Ny?61
return currentPage; fy4JW,c
} &t:MWb;
d~$t{46
/** a~EEow;A
* @param currentPage 5DUPsV
* The currentPage to set. UVU*5U~
*/ 5h7DVr!
publicvoid setCurrentPage(int currentPage){ m:7bynT{
this.currentPage = currentPage; PS]XLz
} |
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/** UzwIV{
* @return #(4hX6?5AI
* Returns the everyPage. (_<n0
*/ 0evZg@JP`
publicint getEveryPage(){ ]qRz!D%@^
return everyPage; #Og_q$})f
} \hc9Rk
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/** Bqgw%_
* @param everyPage *~X\c Z
* The everyPage to set. xGPv3TLH^
*/ ~epkRO="
publicvoid setEveryPage(int everyPage){ {,srj['RS
this.everyPage = everyPage; x7>sy,c
} `8Ix&d3F
4TV9t"Dk+c
/** @)wXP@7
* @return Jt][b
* Returns the hasNextPage. p]HtJt|]
*/ #=m5*}=
publicboolean getHasNextPage(){ ;[ojwcK[ZF
return hasNextPage; 7 c7SU^hD
} [c~zO+x
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/** C^'}{K
* @param hasNextPage sj2+|>
* The hasNextPage to set. \!Pm^FD
.
*/ @m4d 4K@
publicvoid setHasNextPage(boolean hasNextPage){ e9nuQ\=
this.hasNextPage = hasNextPage; xNU}uW>>T
} {fs(+
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/** 57rP@,vj
* @return ygG9ht
* Returns the hasPrePage. ~-x\E#(
*/ ) Lv{
publicboolean getHasPrePage(){ `!BUd
return hasPrePage; q_)DY
f7V}
} [a2/`ywdV
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/** W%x#ps5%
* @param hasPrePage z> SCv;Q
* The hasPrePage to set. Z]dc%>
*/ p w8'+FX
publicvoid setHasPrePage(boolean hasPrePage){ LBzpaLd
this.hasPrePage = hasPrePage; uM$=v]e^4
} hsh
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/** BehV
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* @return Returns the totalPage. XT\;2etVL
* \%(R~H
*/ xxYFWvi
publicint getTotalPage(){ $kdfY'u
return totalPage; Nz8iU@!a
} =0A{z#6
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/** 5|Uub,
* @param totalPage | e+m!G1G
* The totalPage to set. 6%? NNEM
*/ t{ 'QMX
publicvoid setTotalPage(int totalPage){ @#p4QEQA
this.totalPage = totalPage; V6c?aZ,O
} z&eJ?wb
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} 5<61NnZ
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上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 l{k
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个PageUtil,负责对Page对象进行构造: {^~{X$YI
java代码: /c09-$M
(7"qT^s3
='s2S5#1
/*Created on 2005-4-14*/ +_+_`q>]
package org.flyware.util.page; WTXTr0=
x9uA@$l^|
import org.apache.commons.logging.Log; iGR(
import org.apache.commons.logging.LogFactory; bf3)^ 49}
4>(?R[:p)
/** #df Aqg'
* @author Joa E-r/$&D5mP
* |^FDsJUN
*/ 1Eg,iTn2*x
publicclass PageUtil { :D(:(`A=
P0W%30Dh
privatestaticfinal Log logger = LogFactory.getLog
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&Zov9o:gx
(PageUtil.class); :QN,T3i'/3
4}gwMjU-B
/** Odagaca
* Use the origin page to create a new page @NO&3m]
* @param page -i9/1.Z
* @param totalRecords fY>\VY$>
* @return (|Xf=q,Le
*/ (33[N
publicstatic Page createPage(Page page, int { `-EX
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totalRecords){ Y5K!DMKY
return createPage(page.getEveryPage(), jAF
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=\`9 \Gd
page.getCurrentPage(), totalRecords); u6I# D
_
} vG<Mz?wr
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/** xU)~)eK
* the basic page utils not including exception >GqIpfn
G.L4l|%W
handler -6#i~a]
* @param everyPage T_pE 'U%[
* @param currentPage 5C/u`{4]Hg
* @param totalRecords CKj3-rcF(
* @return page 6?2/b`k
*/ x}72jJe`
publicstatic Page createPage(int everyPage, int 7v1}8Uk
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currentPage, int totalRecords){ ""TRLs!:M
everyPage = getEveryPage(everyPage); D7 A{*Tm
currentPage = getCurrentPage(currentPage); *_U
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int beginIndex = getBeginIndex(everyPage, DAJh9I
#~nI^
ggW
currentPage); 0p![&O
int totalPage = getTotalPage(everyPage, ;9d(GP}eE
N\mV+f3A@,
totalRecords); %x L3=4\
boolean hasNextPage = hasNextPage(currentPage, :N(L7&<
:x= ZvAvo
totalPage); Xo }w$q5
boolean hasPrePage = hasPrePage(currentPage); E/Y.f
_/7[=e}y
returnnew Page(hasPrePage, hasNextPage, !dGy"-i$h
everyPage, totalPage, 1 BVivEG
currentPage, ;z!~-ByzL
(Z
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beginIndex);
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} 7J##IH+z35
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privatestaticint getEveryPage(int everyPage){ t4h5R
return everyPage == 0 ? 10 : everyPage; H<dm;cU
} E9QNx62
7vgz=-
MZ#
privatestaticint getCurrentPage(int currentPage){ dEns|r
return currentPage == 0 ? 1 : currentPage; si0jXue~j\
} amgYr$)m
NcRY
Ch
privatestaticint getBeginIndex(int everyPage, int 6SW:'u|90
SbrBlP:G
currentPage){ liPUK #
return(currentPage - 1) * everyPage; ^hTq~ "
} YgrBIul
'N0d==aI
privatestaticint getTotalPage(int everyPage, int mbSJ}3c"
ExV>s* y
totalRecords){ B3e{'14
int totalPage = 0; %q(n'^#Z.y
LR'F/.Dx
if(totalRecords % everyPage == 0) zLC\Rc4
totalPage = totalRecords / everyPage; )=ZWn,ZB
else xs+MvXTC
totalPage = totalRecords / everyPage + 1 ; b'uH4[zX%
`[/BG)4
return totalPage; " ?n~ /9`
} Bu*ge~
Fp|x,-
privatestaticboolean hasPrePage(int currentPage){ 8x[q[
return currentPage == 1 ? false : true; $UgM7V$
} zd"o #(sv
[P,1UO|$B
privatestaticboolean hasNextPage(int currentPage, ;&?NuK
<wc=SMmO
int totalPage){ ?,TON5Fl-
return currentPage == totalPage || totalPage == o1-Zh!*a*
<JDkvpckx.
0 ? false : true; Z3T:R"l;
} |Zncr9b
eB^:+h#A_
8xZN4ck_@
} l^WFMeMD3a
,B h[jb`y
)#M*@e$k
Ga"$_DyM
r68'DJ&m3
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 HmAA?J}
mS0*%[S {
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 ?UQE;0 B
,d@.@a]
`
做法如下: E;9SsA
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 7YkxIzE
n<y!@p^X
的信息,和一个结果集List: N:Q}Lil
java代码: 00n6v;X
bxK1v7
`4gm'C
/*Created on 2005-6-13*/ }`\+_@w
package com.adt.bo; gNo.&G [
~;3N'o
import java.util.List; LezM=om.
aB#qzrr['8
import org.flyware.util.page.Page; 8lT.2H
b_z;^y~
/** y`! 3Z} 7
* @author Joa f'TdYG
*/ =uIu0_v
publicclass Result { Q Y/36gK
4JT9EKo
private Page page; K.dgQ-vn
zl=RK
private List content; MX xRM~
xmT(yv,
/** Ud\Jc:DG
* The default constructor WpWnwQY`#
*/ w f,7
public Result(){ eICk}gfun
super(); NUX0=(k
} oost}%WxN
Sz.jv#Y
/** =pF 6
* The constructor using fields #,0%g1
* a)`b;]+9
* @param page 0' @^PzX
* @param content ~ubGx
*/ )R<hYd
public Result(Page page, List content){ ry/AF
this.page = page; =O<Ul~JRK
this.content = content; +q|2j>k@
} W52AX.Nm
mh2t ' O
/** l+*^P'0u
* @return Returns the content. .u>IjK^
*/ 1aS[e%9Mg
publicList getContent(){ Y\Odj~Mj
return content; 2n2{Oy>L
} Sdy\s5
+3(1QgYM%
/** KE]!7+8-
* @return Returns the page. AVyqtztQ
*/ k
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public Page getPage(){ QyuSle
return page; ,)@Q,EHN;
} 3tMs613
Vp.($
/** fq~<^B
* @param content k^}8=,j}
* The content to set. XnHcU=~q
*/ h1^q};3!W\
public void setContent(List content){ ~ou*'
w@
this.content = content; kQxY"HD
} !i&^H,
<iajtq<Z
/** ek1YaE
* @param page 4=9To|U*
* The page to set. G,FYj'<!7,
*/ #DXC6f
publicvoid setPage(Page page){ )cbe4
this.page = page; :<YcV#!P
} @kK${
} vd
c k
3)^-A4~E
{.GC7dx
)@DH&
p6$ QTx
2. 编写业务逻辑接口,并实现它(UserManager, z_~5c
UN>!#Ji:$
UserManagerImpl) snT! 3t
java代码: +R@5e+auQ.
K'+GK S7.
*Em 9R
/*Created on 2005-7-15*/ [ Lt1OdGl
package com.adt.service; #/Y t4n
AF g*
import net.sf.hibernate.HibernateException; w4H3($
K
_Pjo9z
9
import org.flyware.util.page.Page; (1T2?mO
qba<$
import com.adt.bo.Result; T]l_B2.
yd2v_
/** 3/RmJ`c{
* @author Joa ;aExEgTq
*/ lJP6sk
publicinterface UserManager { aL$m
h?jy'>T?b2
public Result listUser(Page page)throws WX&Man!f
)sWdN(E3
HibernateException; oM/(&"
Nc:, [8{l
} /-Y*V*E
W2G`K+p
al$G OMi
.9_]8T
3/+9#
java代码: $m] ~d6
n*(Vf'k
D$
zKkPYI
/*Created on 2005-7-15*/ cobq+Iyu
package com.adt.service.impl; +/y 3]}
M)C.bo{p
import java.util.List; }2:/&H'
*Nloa/a&9
import net.sf.hibernate.HibernateException; pRe, B'&
UKMr,{iy
import org.flyware.util.page.Page; "z)dz,&T
import org.flyware.util.page.PageUtil; NTS
tk{s,
+h_'hz&HlS
import com.adt.bo.Result; Me;@/;c(
import com.adt.dao.UserDAO; tz\7,yGT
import com.adt.exception.ObjectNotFoundException; m/gl7+
import com.adt.service.UserManager; p8o
~
D ksSD
/** %B5.zs]Of
* @author Joa )F4H'
*/ /Aooh~
publicclass UserManagerImpl implements UserManager { a@$ U?=\e
7K>FCT
private UserDAO userDAO; &;S.1tg
t-*oVX3D
/** Z(Fsk4,
* @param userDAO The userDAO to set. NXb_hF
*/ 6Ko[[?Lf[
publicvoid setUserDAO(UserDAO userDAO){ 0i/l2&x*k]
this.userDAO = userDAO; KoVy,@
} cf)2GoV>e
0(\ybppx
/* (non-Javadoc) S^'?sfq
* @see com.adt.service.UserManager#listUser (dn(:<_$
01<~~6A
(org.flyware.util.page.Page) 12BTZ
*/ 0j\?zt?
public Result listUser(Page page)throws Se7NF@>9_
W}p>jP}
HibernateException, ObjectNotFoundException { 1^ZQXUzl%i
int totalRecords = userDAO.getUserCount(); (oO*|\9u
if(totalRecords == 0) :c3}J<Z
throw new ObjectNotFoundException |3`Sd;^;
)/kkvI()l
("userNotExist"); {)nm
{IV,
page = PageUtil.createPage(page, totalRecords); G&$+8r
List users = userDAO.getUserByPage(page); I)Y ^_&=
returnnew Result(page, users); ,4wVQ(,?cd
} T;K,.a8bU
rM<|<6(L
} X-&t!0O4}`
#
le<R
b-R!oP+vP
g((glr)6M
M&o@~z0
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 aZEi|\VU
"Opk:;.
询,接下来编写UserDAO的代码: O Z<iP
3. UserDAO 和 UserDAOImpl: }z:g}".4
java代码: )\#w=P
3`[f<XaL
5W_u|z+/g
/*Created on 2005-7-15*/ S\=j; Uem
package com.adt.dao; jq#gFt*
PhL }V|W>
import java.util.List; !dQG 5v
COPH)Bdq.
import org.flyware.util.page.Page; cr Hd$~q,
o&}!bq]
import net.sf.hibernate.HibernateException; dx}) 1%
B@g 0QgA
/** G;:n*_QXE
* @author Joa 1M+o7HO.mG
*/ epM;u
publicinterface UserDAO extends BaseDAO { /.{4
KW5
.U|irDO
publicList getUserByName(String name)throws nI4Kuz`dF
R!IODXP=
HibernateException; IGz92&y
;v%Fw!b032
publicint getUserCount()throws HibernateException; HnU; N S3J
(3 xCW
publicList getUserByPage(Page page)throws vW,dJ[N6jm
wz^Q,Od
HibernateException; Ojqbj0E9
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} s&:LY"[`
L&V;Xvbu%
70bI}/u
dl_ h0
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java代码: OI0#@_L&
2z9\p%MX
_K"|}bM
/*Created on 2005-7-15*/ W>3[+wB
package com.adt.dao.impl; e~C5{XEE
wGdnv}#
import java.util.List; {(;dHF%{
mLApF5Hy
import org.flyware.util.page.Page; GPBp.$q+B
hu}`,2
import net.sf.hibernate.HibernateException; V5w00s5?%
import net.sf.hibernate.Query; tGHZU^B:}
`x%v&>
import com.adt.dao.UserDAO; jo 0
d#
'z$ BgXh\
/** u[nx?!
* @author Joa xCU^4DO3p
*/ q =sEtH=
public class UserDAOImpl extends BaseDAOHibernateImpl ):"Z7~j=
umPd+5i
implements UserDAO { Q;r9>E!
48;6C g
/* (non-Javadoc) ct,B0(]
* @see com.adt.dao.UserDAO#getUserByName X"_,#3Ko!
CqW:m*c
(java.lang.String) ?d@3y<A,~
*/ #ra"(/)
publicList getUserByName(String name)throws $n_'#m2LE
O.61-rp
HibernateException { $HVus=D"
String querySentence = "FROM user in class ~uqpF-.
B#RBR<MFC
com.adt.po.User WHERE user.name=:name"; >YP6/w,e
Query query = getSession().createQuery g '2'K
e$HN/O
(querySentence); B*=m%NXf
query.setParameter("name", name); #[ZF'9x
return query.list(); Ik[aiz
} Ay?KE{Qs '
nx{_^sK
/* (non-Javadoc) 'Cw&9cL9w
* @see com.adt.dao.UserDAO#getUserCount() b[5$$_[
*/ R@*mMWW,
publicint getUserCount()throws HibernateException { #p'Xq
}]
int count = 0; +ob<?
T
String querySentence = "SELECT count(*) FROM 9 0PF)U
.|>zQ(7YC
user in class com.adt.po.User"; q\+khy,k
Query query = getSession().createQuery OZ{YQ}t{^1
S$9>9!1>*
(querySentence); SN
w3xO!;&
count = ((Integer)query.iterate().next BET3tiHV
n~~0iU)
()).intValue(); /S4$qr cM
return count; j1/.3\
} u,h ,;'J
fL^+Qb}
/* (non-Javadoc) )_[eqr
* @see com.adt.dao.UserDAO#getUserByPage >K]s)VuWR
'Xj9sAB
(org.flyware.util.page.Page) &f12Q&jY7
*/ w-f[h
publicList getUserByPage(Page page)throws P#e1?
{NmpTb
HibernateException { uZ[7[mK}n7
String querySentence = "FROM user in class P .I<.e
lw/zgR#|
com.adt.po.User"; ,-!h
Query query = getSession().createQuery y b 7
Po+I!TL'
(querySentence); #<_gY
query.setFirstResult(page.getBeginIndex()) sK1YmB :~a
.setMaxResults(page.getEveryPage()); oWCy%76@
return query.list(); 4sU*UePr
} j?!BHNs
~Sq!P
} :{#%_^}k
\}CQo0v
|%wgux`z
9 Vn
ZUDdLJ
至此,一个完整的分页程序完成。前台的只需要调用 Vz=ByyC
82w;}(!
userManager.listUser(page)即可得到一个Page对象和结果集对象 lr>:S
Xz/5Wis4
的综合体,而传入的参数page对象则可以由前台传入,如果用 z^@.b
IZr~h9
webwork,甚至可以直接在配置文件中指定。 [V vTR#^
7d9kr?3(U
下面给出一个webwork调用示例: &G#LQl
java代码: 3Z,J&d`[
+TA'P$j
\BIa:}9O
/*Created on 2005-6-17*/ +w'"N
package com.adt.action.user; l/=2P_8+Z
x2-i1#j`;
import java.util.List; G8]DK3#
j$2rU'
import org.apache.commons.logging.Log; cJ CKxj
import org.apache.commons.logging.LogFactory; +ZuT\P&kR5
import org.flyware.util.page.Page; I+qg'mo
:0G_n\
import com.adt.bo.Result; XUI9)Ne
import com.adt.service.UserService; $-HP5Kj(k-
import com.opensymphony.xwork.Action; F0yvV6;
M:%6$``
/** 8KxBN)fO;
* @author Joa |I; tBqN{u
*/ />wM#)o2
publicclass ListUser implementsAction{ "6[a%f#Q
$P=B66t
^
privatestaticfinal Log logger = LogFactory.getLog (s:ihpI
cr}T ? $\K
(ListUser.class); v|\<N!g
A&HN7C%X
private UserService userService; +[LG>
<F>^ffwGH-
private Page page; Iq76JJuCb
'7lHWqN<
privateList users; QNH-b9u>8
nRP|Qt7>
/* & XS2q0-x
* (non-Javadoc) }6Ut7J]a|
*
1z .
* @see com.opensymphony.xwork.Action#execute() 4rcNBmA,
*/ bOEO2v'cQ
publicString execute()throwsException{ +"sjkdum1
Result result = userService.listUser(page); VR8 kY&
page = result.getPage(); #hp7@ Tu
users = result.getContent(); 'H19@b5rx
return SUCCESS; K;:_UJ>t
} 7H$I9e
[uJfmr EH
/** 6MewQ{h i
* @return Returns the page. fGeDygV^`
*/ y4@zi "G
public Page getPage(){ E{LLxGAEZ
return page; oFO)28Btv
} n!Dr:$
\wJ2>Q
/** a Uy!(Y
* @return Returns the users. _1c0pQ ^}3
*/ ?S*Cvr+=4
publicList getUsers(){ #[
H4`hZ
return users; &oz^dlw
} p)u?x)w=
Po)!vL"
/** j&(Yk"j+
* @param page I pp#{'Do
* The page to set. P{bRRn4Z
*/ GiZv0>*x
publicvoid setPage(Page page){ Mr0<b?I
this.page = page; 6UAn#d9
} ;+Dq3NE
As}eI!
/** ?Iin/ <y
* @param users 9wTN*y
* The users to set. jkQ%b.a
*/ y[D8r Fw
publicvoid setUsers(List users){ f:\)oIW9Kk
this.users = users;
46^9O
5J
} >U~{WM$"Y
`{Jo>L.
/** a-cLy*W,~
* @param userService [%0{7pz}
* The userService to set. rN3qTp
*/ \&6^c=2=
publicvoid setUserService(UserService userService){ @#j?Z7E|
this.userService = userService; iL$~d@AEn
} FI(iqSJ6
} d3[O!4<T
>=6 j:
h7P<3m}
n@JZ 2K4
wv7XhY}
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, 9hTzi+'S
f?qp*
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 {^T_m)|n
j; MQ_?"iN
么只需要: FwjmC%iY
java代码: !RXG{1:
%w3Y!7+
>p`ZcFNs"
<?xml version="1.0"?> vG{lxPIj
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork d:L|BkQ7*
6CV9ewr
1.0//EN" "http://www.opensymphony.com/xwork/xwork- m]?C @ina
.eHOG]H
1.0.dtd"> z@8W
/$U<S"
<xwork> W=S<DtG2
${F4x "x
<package name="user" extends="webwork- +F4SU(T
q` 0wG3
interceptors"> -cONC9=
BN~gk~t_
<!-- The default interceptor stack name S8d X8,qg
d7]~t|
--> _C%:AFPP>
<default-interceptor-ref c+:XaDS-
)ppIO"\
name="myDefaultWebStack"/> c-y`Hm2"
'@{Mq%`
<action name="listUser" k
d9<&.y{
Ncr*F^J4
class="com.adt.action.user.ListUser"> YAsE,M+
<param =j~vL`d2]
a/{M2
name="page.everyPage">10</param> VR XK/dZ
<result K(3_1*e
)j+G4
name="success">/user/user_list.jsp</result> JC.nfxG@:
</action> (3Dz'X
6%B)
</package> ):-Ub4A\
u Wxl\+_i
</xwork> =v{Vl5&>?
,<t)aZL,A;
Tl!}Rw~Pg
o JX4+uJ
UGP,/[XI
aCF=Og
这样就可以通过配置文件和OGNL的共同作用来对page对象设置初值 g2%fla7r
KL\hV .6
了。并可以通过随意修改配置文件来修改每页需要显示的记录数。 d` X1cG
!dV2:`|+
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 @#2KmM~I
xO{$6M3-~
k@[{_@>4^
~zYk,;m
D$U`u[qjtS
我写的一个用于分页的类,用了泛型了,hoho Pk{%2\%&2
d#CAP9n;'
java代码: &e\UlM22
X.GK5Phd
VC X^D)[-
package com.intokr.util; =$-+~
a797'{j#PI
import java.util.List; 2_GbK-
WNSY@q
/** gVI{eoJ
* 用于分页的类<br> n09P!],Xa
* 可以用于传递查询的结果也可以用于传送查询的参数<br> eL_Il.:
* &7r73~TXm
* @version 0.01 Bp-e< :
* @author cheng dT7!+)s5-
*/ ;R([w4[~
public class Paginator<E> { 3_ ZlZ_Tq
privateint count = 0; // 总记录数 [tk6Kx8a
privateint p = 1; // 页编号 M.9w_bW]#D
privateint num = 20; // 每页的记录数 uqv S
privateList<E> results = null; // 结果 w_P2\B^
%+iAL<S
/** 2&zklXuo:
* 结果总数 (9Of,2]&E
*/ uQYenCNXS
publicint getCount(){ ?UV|m
return count; b ;>?m
} Kz"&:&R"
r1BL?&X-
publicvoid setCount(int count){ bJcO,M:2
this.count = count; "i,ZG$S#E
} ZkryoIQ%=
:[&QoEZW
/** ^#!\VGnL
* 本结果所在的页码,从1开始 y&(pt!I
* .Vrl:
* @return Returns the pageNo. OCELG~
*/ >BZ,g!N,J}
publicint getP(){ /s@j{*Om
return p; s+E:
7T9P
} bTMgEY
5KTPlqm0qF
/** 6[,7g&C
* if(p<=0) p=1 @77+K:9I7
* $ZkT G
* @param p i`w)dS
*/ srhI%Zj
publicvoid setP(int p){ dVSQG947i:
if(p <= 0) Pq,iR J
p = 1; phR:=Ox|1
this.p = p; $;rvKco)%
} W[:CCCDL
`<-/e%8
/** <k 'zz:[c!
* 每页记录数量 4BZ7R,m#.
*/ [r1dgwh8
publicint getNum(){ *|ef #-|D
return num; 1&RB=7.h
} Vqr]Ui
ar_@"+tZ
/** jLn|zK
* if(num<1) num=1 !JtM`x/yR
*/ B,] AfH
publicvoid setNum(int num){ 3oV2Ek<d
if(num < 1) pV O{7I
num = 1; Y+h
?HS
this.num = num; vxS4YR b
} V
n+a-v
(7ujJ}#,
/** 2(5/#$t
* 获得总页数 eo~b]D
*/ /!%?I#K{Wq
publicint getPageNum(){ vX_;Y#uD
return(count - 1) / num + 1; ?R_fg
} A
b+qLh&?
^VEaOKMr
/** V -_MwII-
* 获得本页的开始编号,为 (p-1)*num+1 $o/i /
wcj
*/ rX0 ?m:&m
publicint getStart(){ R'pfA
B|!
return(p - 1) * num + 1; M+I9k;N6&
} ,/&|:PkS
JNo[<SZb
/** ^<_rE- k
* @return Returns the results. mkq246<D~
*/ =@c;%x
publicList<E> getResults(){ #pyFIUr=w
return results; -qBdcbi|x)
} v\E6N2.S
86>@.:d
public void setResults(List<E> results){ r4d#;S9{o
this.results = results; WD1>{TSn
} 1'P4{T0 [
bokr,I3
public String toString(){ _9dW+
StringBuilder buff = new StringBuilder NKc<nYdK?
(*kKfg4Wj
(); nd$92H
buff.append("{"); G7i0P j
buff.append("count:").append(count); N) PkE>%X
buff.append(",p:").append(p); 9z`72(
buff.append(",nump:").append(num); {yB0JL}n
buff.append(",results:").append ]L2b|a3
ui-]%~
(results); ^CgN>-xZ?#
buff.append("}"); MS:,I?
return buff.toString(); Dp4x\97O
} uzT+,
/N#=Tol
} hAt4+O&P
;GKL[tI"
oF a,IA