Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 vnZC,J `
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 338k?nHxv
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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 l)l^[2
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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 %aVq+kC h
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分页支持类: ZeaA%y67U
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java代码: P:MT*ra*,
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package com.javaeye.common.util; K^<BW(s
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import java.util.List; UhQj
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publicclass PaginationSupport { A@{PZ
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publicfinalstaticint PAGESIZE = 30; >V8-i`
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privateint pageSize = PAGESIZE; -**g~ty)
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privateList items; 7}5JDG
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privateint totalCount; |"CZ T#
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privateint[] indexes = newint[0]; y,,dCca
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privateint startIndex = 0; 4yA+h2
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public PaginationSupport(List items, int N]=q|D
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totalCount){ ^KT Y?
setPageSize(PAGESIZE); scz&h#0V
setTotalCount(totalCount); [MM~H0=s
setItems(items); !Pfr,a
setStartIndex(0); 7CURhDdk
} m'=Crei
uGK.\PB$
public PaginationSupport(List items, int a![{M<Y~
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totalCount, int startIndex){ h_,i&d@(
setPageSize(PAGESIZE); wc^tgE
setTotalCount(totalCount); X[BIA+6
setItems(items); 0)e\`Bv
setStartIndex(startIndex); A&Usddcp
} tGE$z]1c@
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public PaginationSupport(List items, int hT&Y#fh
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totalCount, int pageSize, int startIndex){ >7T'OC
setPageSize(pageSize); h_3E)jc
setTotalCount(totalCount); 0#Y5_i|p
setItems(items); a:OQGhc=
setStartIndex(startIndex); ~1AgD-:Jz
} `MN4uC
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publicList getItems(){ CXx*_@}MU
return items; \\H}`0m:
} '"/=f\)u
!6O(-S2A
publicvoid setItems(List items){ .glA
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this.items = items; ;)z:fToh
} Y0dEH^I
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publicint getPageSize(){ GdxnpE
return pageSize; V]e 8a"/[{
} Eib5
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publicvoid setPageSize(int pageSize){ bP$dU,@p~
this.pageSize = pageSize; +YKi,
} hPkWCoQpq
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publicint getTotalCount(){ ub#a`
return totalCount; CMG&7(MR
}
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publicvoid setTotalCount(int totalCount){ N&+x+;Kx
if(totalCount > 0){ $)ijN^hV
this.totalCount = totalCount; U175{N%3
int count = totalCount / c&?m>2^6
/}fHt^2H
pageSize; (!7sE9rP
if(totalCount % pageSize > 0) r|fL&dtr
count++; Zd}9O jz5
indexes = newint[count]; m_?~OL S
for(int i = 0; i < count; i++){ D4lG[qb
indexes = pageSize * 0oZ=
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} [")o.(
}else{ uLL]A>vR
this.totalCount = 0; +yH7v5W
} Ms5ap<q#
} =_ ./~
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publicint[] getIndexes(){ WwBOM~/`2
return indexes; ;!mzyb*
} L:pYn_
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publicvoid setIndexes(int[] indexes){ 2W96Zju\
this.indexes = indexes; HV!m8k=6
} JPc+rfF
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publicint getStartIndex(){ +\c5]`
return startIndex; k}kQI~S9
} ?FeYN+qR
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publicvoid setStartIndex(int startIndex){ 7uS~MW
if(totalCount <= 0) 0w\zLU
this.startIndex = 0; 7Oa#c<2]
elseif(startIndex >= totalCount) Pg0x/X{t
this.startIndex = indexes QQ*hCyw!
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[indexes.length - 1]; 6xe*E[#k\
elseif(startIndex < 0) nwB_8mN|
this.startIndex = 0; QT<
}]
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else{ 1R{!]uh
this.startIndex = indexes Q_Q''j(r6b
['X]R:3h
[startIndex / pageSize]; F3v!AvA|
} 1EO7H{E=
} pMx*F@&nU
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publicint getNextIndex(){ (
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int nextIndex = getStartIndex() + G C),N\@Q
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pageSize; j^j1
if(nextIndex >= totalCount) \:# L)
return getStartIndex(); av}k)ZT_
else eueH)Xkf
return nextIndex; G7`ko1-
} \Xt7`I<
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publicint getPreviousIndex(){ '8RsN-w
int previousIndex = getStartIndex() - zU kgG61
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pageSize; )BZ.Sv
if(previousIndex < 0) KQaxvU)L
return0; @w#-aGJO
else q1$N>;&
return previousIndex; p*R;hU
} uB]7G0g:
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} ;v)JnbsH}
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抽象业务类 F 5bj=mI
java代码: F'={q{2wH
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/** M)J5;^["
* Created on 2005-7-12 9-VNp;V
*/ -j#2}[J7
package com.javaeye.common.business; _UMg[Um
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import java.io.Serializable; :}L[sl\R
import java.util.List; U8s2|G;K
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import org.hibernate.Criteria; r_)' Ps
import org.hibernate.HibernateException; P%V'4p c
import org.hibernate.Session; k_L7 kvpt
import org.hibernate.criterion.DetachedCriteria; ~RW+GTe
import org.hibernate.criterion.Projections; |B?m,U$A!
import AP n| \
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org.springframework.orm.hibernate3.HibernateCallback; :[p}
import XV7Ex\D*
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org.springframework.orm.hibernate3.support.HibernateDaoS VZp5)-!\
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upport; O@T9x$
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import com.javaeye.common.util.PaginationSupport; e&|'I"
@wGPqg
public abstract class AbstractManager extends SB;&GHq"n
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HibernateDaoSupport { ^]>O;iB?
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privateboolean cacheQueries = false; m4[ ;(1
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privateString queryCacheRegion; FZ{h?#2?
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publicvoid setCacheQueries(boolean CmP9Q2
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cacheQueries){ G)AqbY
this.cacheQueries = cacheQueries; MD}w Y><C
} f&NgS+<K$
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publicvoid setQueryCacheRegion(String ,Q3T
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queryCacheRegion){ m<<+
this.queryCacheRegion = a{ L%7
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queryCacheRegion; ~dyTVJ$
} bbDZ#DK"
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publicvoid save(finalObject entity){ /7(W?xOe
getHibernateTemplate().save(entity); paA(C|%{
} AwCcK6N1
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publicvoid persist(finalObject entity){ Hc;[Cs0
getHibernateTemplate().save(entity); f$o_e90mu
} vz@A;t
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publicvoid update(finalObject entity){ gT6z9
getHibernateTemplate().update(entity); &pxg.
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} J@/kIrx
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publicvoid delete(finalObject entity){ CQc+#nRe
getHibernateTemplate().delete(entity); o3XvRj
} @JiLgIe`
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publicObject load(finalClass entity, %HhBt5w
,5P0S0*{
finalSerializable id){ [CTnXb
return getHibernateTemplate().load '9%\;
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(entity, id); <X#C)-.
} ^7`BP%6
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publicObject get(finalClass entity, ~V:\ _{mE
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finalSerializable id){ IY1//9
return getHibernateTemplate().get 8$]1M,$r
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(entity, id); "-E\[@/
} &.F4b~A7
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publicList findAll(finalClass entity){ 1;* cq
return getHibernateTemplate().find("from FBG4pb9=~
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" + entity.getName()); `C,n0'PL.
} x[|}.Ew
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publicList findByNamedQuery(finalString \Zb;'eDv
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namedQuery){ 2/U.|*mH
return getHibernateTemplate qRu~$K
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().findByNamedQuery(namedQuery); Q@= Q0
} zWnX*2>b
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publicList findByNamedQuery(finalString query, \wmN
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finalObject parameter){ M+oHtX$
return getHibernateTemplate XjB W9a
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().findByNamedQuery(query, parameter);
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} \a<wKTkn
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publicList findByNamedQuery(finalString query, g9OY<w5s]
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finalObject[] parameters){ g/4[N{Xf
return getHibernateTemplate (xycJ`N
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().findByNamedQuery(query, parameters); ??5Q)Erm1
} pG_;$8Hc
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publicList find(finalString query){ yER(6V'\iQ
return getHibernateTemplate().find y4yhF8E>;U
^"E^zHM(
(query); UB@Rs|)
} ip\sXVR
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publicList find(finalString query, finalObject rDtY[
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parameter){ JhYe6y[q
return getHibernateTemplate().find Z<oaK
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(query, parameter); MyOd,vU
} -au^;CM
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public PaginationSupport findPageByCriteria 5#6|j?_a
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(final DetachedCriteria detachedCriteria){ 'I|v[G$l
return findPageByCriteria LPXi+zj
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); ! 6 #X>S14
} 'JtBZFq
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public PaginationSupport findPageByCriteria /|w6:;$;mn
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(final DetachedCriteria detachedCriteria, finalint e
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+ SzU
startIndex){ 3qgS&js 7
return findPageByCriteria kb%;=t2
A.F%Ycq
(detachedCriteria, PaginationSupport.PAGESIZE,
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startIndex); T}Tp$.gB
} 3=#<X-);
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public PaginationSupport findPageByCriteria e}voV0y\v:
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(final DetachedCriteria detachedCriteria, finalint q~Hn-5H4Q
y
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pageSize, _{ue8kGt
finalint startIndex){ ,O5NLg-
return(PaginationSupport) E*&vy
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getHibernateTemplate().execute(new HibernateCallback(){ BkAm/R
publicObject doInHibernate pp?D7S
m[osg< CR_
(Session session)throws HibernateException { TvoyZW\?w
Criteria criteria = >-?f0K
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detachedCriteria.getExecutableCriteria(session); 5PCqYN(:B
int totalCount = `?H]h"{7Q
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((Integer) criteria.setProjection(Projections.rowCount t|?ez4/{z
j a[Et/r
()).uniqueResult()).intValue(); @/~omg}R
criteria.setProjection [&[k^C5
1dY}\Sp
(null); PN%zIkbo
List items = ^S<Y>Nm]
';Ea?ID
criteria.setFirstResult(startIndex).setMaxResults UBKu/@[f@
n6=By|jRh
(pageSize).list(); Wb,KjtX
PaginationSupport ps = },?kk1vIT{
f^ZRT@`O
new PaginationSupport(items, totalCount, pageSize, >~rTqtKd
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startIndex); FgnTGY}
return ps; t^-d/yKt0w
} R+:yVi[F]U
}, true); _%Bi: HG0
} &3>)qul
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public List findAllByCriteria(final ;]puq
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DetachedCriteria detachedCriteria){ ;LfXi 8)
return(List) getHibernateTemplate T.F!+
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().execute(new HibernateCallback(){ P;y45b
publicObject doInHibernate 3yme1Mb
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(Session session)throws HibernateException { 0JS?; fk
Criteria criteria = bRDYGuC
e
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detachedCriteria.getExecutableCriteria(session); OKZV{Gja
return criteria.list(); g'f@H-KCD
} tIi&;tw]
}, true); BR_1MG'{)$
} Z#jZRNU%ox
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public int getCountByCriteria(final iU918!!N
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DetachedCriteria detachedCriteria){ ITQA0PISL
Integer count = (Integer) w(Ovr`o?9t
)}R0Y=e
getHibernateTemplate().execute(new HibernateCallback(){ yN0Vr\r2
publicObject doInHibernate ]! &FKy
}Bh8=F3O
Q
(Session session)throws HibernateException { Y Uc+0
Criteria criteria = w/<L
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detachedCriteria.getExecutableCriteria(session); "^[ 'y7i
return bP#:Oi0v`
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criteria.setProjection(Projections.rowCount v"$L702d$\
7"D",1h
()).uniqueResult(); 2|y"!JqE1
} +/7?HGf
}, true); 2"Q|+-Io
return count.intValue(); /N+dQe
} @7c?xQVd$
} TqQB@-!
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用户在web层构造查询条件detachedCriteria,和可选的 nAato\mM
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 z9Mfd#5?>P
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PaginationSupport的实例ps。 sdrfsrNvB-
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ps.getItems()得到已分页好的结果集 0auYG><=
ps.getIndexes()得到分页索引的数组 9RL`<,Q
ps.getTotalCount()得到总结果数 aK~8B_5k8
ps.getStartIndex()当前分页索引 8`{:MkXP
ps.getNextIndex()下一页索引 aKDKmHd
ps.getPreviousIndex()上一页索引 a!SiX
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 3`?7<YJ
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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 .43'HV
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一下代码重构了。 \l0[rcEf
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我把原本我的做法也提供出来供大家讨论吧: fbvL7*
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首先,为了实现分页查询,我封装了一个Page类: A\DCW
java代码: S@tLCqV4
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/*Created on 2005-4-14*/ 5;WH:XM
package org.flyware.util.page; ;;t yoh~t
MchA{p&Ol
/** h"W,WxL8
* @author Joa A{zN| S[
* (mB&m@-N
*/ |-ALklXr
publicclass Page { Rv>-4@fMJ
Q{>k1$fkV
/** imply if the page has previous page */ Yh7t"=o
privateboolean hasPrePage; KF}hV9IU
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/** imply if the page has next page */ = svN#q5s
privateboolean hasNextPage; ~8+ Zs
@
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/** the number of every page */ o/)h"i0P
privateint everyPage; JR|ck=tq
1&OW4_
/** the total page number */ q
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privateint totalPage; XT*sGM
:OZrH<SW
/** the number of current page */ _f,C[C[e&
privateint currentPage; djZqc5t
S hWJ72c
/** the begin index of the records by the current :-Z2:/P
qR{=pR
query */ cjY-y-vO
privateint beginIndex; 6MW{,N
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/** The default constructor */ D_7,m%Z:
public Page(){ -2[a2^a'
dT8S~-d%
} X?',n
1
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/** construct the page by everyPage 00y!K
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* @param everyPage uzPVTo|=
* */ q`-N7 ,$T
public Page(int everyPage){ 33q}CzK
this.everyPage = everyPage; ^
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} JQI: sj
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/** The whole constructor */ A)!*]o>U
public Page(boolean hasPrePage, boolean hasNextPage, '<<t]kK[N
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int everyPage, int totalPage, p
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int currentPage, int beginIndex){ 3$R1ipb
this.hasPrePage = hasPrePage; e !Y~Qy
this.hasNextPage = hasNextPage; Avc%2+
this.everyPage = everyPage; \\qZl)P_
this.totalPage = totalPage; 59A}}.@?m
this.currentPage = currentPage; )akoa,#%6c
this.beginIndex = beginIndex; t:Q*gWRh
} A/s?x>QA
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/** f}e`XA?
* @return
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* Returns the beginIndex. # W']6'O
*/ Sm|6 %3
publicint getBeginIndex(){ "+s++@
z
return beginIndex; tWRC$
} >GRxHK@G
RrB&\9=
/** b$joY*< 6
* @param beginIndex >bW#Zs,6
* The beginIndex to set. VONDc1%ga
*/ eauF~md,
publicvoid setBeginIndex(int beginIndex){ =^?/+p8k
this.beginIndex = beginIndex; hgq;`_;1,
} ZECfR>`x
e^voW"?%
/** hVY$;s
* @return 2+XAX:YD
* Returns the currentPage. })%{AfDRF
*/ h_'*XWd@
publicint getCurrentPage(){ AwR=]W;j
return currentPage; 5H^(2w
} @yYkti;4-
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/** t6c4+D'{].
* @param currentPage gbA_DZ
* The currentPage to set. [/r(__.
*/ ob]w;"
publicvoid setCurrentPage(int currentPage){ XCQs2CHt
this.currentPage = currentPage; h*\%vr
} Le^ n +5x
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/** SXh-A1t
* @return wCBplaojJ
* Returns the everyPage. :ws<-Qy
*/ (bS&D/N.
publicint getEveryPage(){ }SZd
return everyPage; "{t$nVJ
} +}AI@+
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/** 8oGRLYU N
* @param everyPage 2 %]X+`+O
* The everyPage to set. AbM'3Mkz
*/ n$R)>nY
publicvoid setEveryPage(int everyPage){ }@)[5N#A|
this.everyPage = everyPage; [-w%/D%@
} y~V(aih}D
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/** 53h0UL
* @return ca9X19NG
* Returns the hasNextPage. ckn(`I
*/ h68 xet;
publicboolean getHasNextPage(){ &p,]w~d,U
return hasNextPage; MdF2Gk-9
} (9)Q ' 'S
]:n,RO6
/** ['D]>Ot68
* @param hasNextPage <_+X 88
* The hasNextPage to set. "dlVk~
*/ x{n=;JD
publicvoid setHasNextPage(boolean hasNextPage){ ;Rf'P}"]
this.hasNextPage = hasNextPage; iy"*5<;*DD
} =(^3}x
l^}c!
/** b,@/!ia
* @return X8\GzNE~R
* Returns the hasPrePage. An@t?#4gxi
*/ ssL\g`xe
publicboolean getHasPrePage(){ 7>RY/O;Z,
return hasPrePage; rN>R|].
} *zLMpL_
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IJ
/**
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* @param hasPrePage uAk.@nfiEv
* The hasPrePage to set. ?7A>+EY
*/ a q-~B~c`g
publicvoid setHasPrePage(boolean hasPrePage){ GvAb`c=
this.hasPrePage = hasPrePage; tJmTBsn
} 2 E=L8<
;VK.2^jW!
/** ~J]qP #C
* @return Returns the totalPage. qP
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* '"Nr, vQo
*/ gGuO
publicint getTotalPage(){ 05R@7[GWq
return totalPage; &,/S`ke=
} - YBY[%jF>
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/** A@'OJRc
* @param totalPage $~kA
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* The totalPage to set. A%vbhD2;W
*/ {`_i`
publicvoid setTotalPage(int totalPage){ +T+#q@
this.totalPage = totalPage; OTv)
} JGZBL{8
I =#$8l.*
} EX"yxZ~
K NOIZj
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CN?gq^
上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 )5H?Vh>36
Fzcwy V
个PageUtil,负责对Page对象进行构造: }0 ?3:A
java代码: o;*Q}Gr<M
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/*Created on 2005-4-14*/ `@%LzeGz
package org.flyware.util.page; X-/]IHDN
3U}%2ARo_
import org.apache.commons.logging.Log; ^f@=:eWI
import org.apache.commons.logging.LogFactory; BLFdHB.$T
=|9!vzG4
/** 3$/IC@+
* @author Joa ';"VDLb3
* MfkZ
*/ T>>c2$ x
publicclass PageUtil { Xc.`-J~Il
#z42C?V
privatestaticfinal Log logger = LogFactory.getLog cb bFw
s[ N@0
(PageUtil.class); zeRyL3fnmb
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/** 0`H#
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* Use the origin page to create a new page qSQ~D(tO
* @param page 1*7@BP5
* @param totalRecords kcEeFG;DQ
* @return
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*/ @nf`Gw ;
publicstatic Page createPage(Page page, int [ hsds\
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totalRecords){ P~dcW
return createPage(page.getEveryPage(), =u;MCQ[
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page.getCurrentPage(), totalRecords); !9x}
} R-Sym8c
.C(tMF]D,
/** JI5Dy>u:
* the basic page utils not including exception X?Au/
a{e4it
handler B<-Wea
* @param everyPage (.,G=\!
* @param currentPage >3bCTE
* @param totalRecords ,?3G;-
* @return page E"0>yl)
*/ >d6| ^h'0
publicstatic Page createPage(int everyPage, int adw2x pj
.(vwIb8\_
currentPage, int totalRecords){ %)wjR/o
everyPage = getEveryPage(everyPage); Hv, LS;W
currentPage = getCurrentPage(currentPage); 2pAW9R#UV-
int beginIndex = getBeginIndex(everyPage, v0y(58Rz.
0IpmRH/
currentPage); r*Xuj=
int totalPage = getTotalPage(everyPage, ;d?R:Uw8
F[0]/
totalRecords); Js;h%
boolean hasNextPage = hasNextPage(currentPage, hOeRd#AQK
pJ{Y
lS{
totalPage); < vP=zk
boolean hasPrePage = hasPrePage(currentPage); ?#fQ~ s
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returnnew Page(hasPrePage, hasNextPage, 'PHl$f*k
everyPage, totalPage, +h$
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currentPage, cnLro
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beginIndex); #/]nxW.S
} ;Xw~D_uv
d'2A,B~_*
privatestaticint getEveryPage(int everyPage){ ~5g ~;f[4
return everyPage == 0 ? 10 : everyPage; `{Ul!
} YS ][n_
qWw=8Bq
privatestaticint getCurrentPage(int currentPage){ o(HbGHIP
return currentPage == 0 ? 1 : currentPage; <QvOs@i*
}
@8
6f
+v\oOBB)
privatestaticint getBeginIndex(int everyPage, int *`U~?q}
0aAoV0fMDz
currentPage){ 2?x4vI
np;
return(currentPage - 1) * everyPage; BuwY3F\-O
} Xeajxcop#
4R*,VR.K
privatestaticint getTotalPage(int everyPage, int #b`ke/P
fZ. ONq
totalRecords){ *](iS
int totalPage = 0; ix$bRdl
_j3f Ar(V
if(totalRecords % everyPage == 0) BzzTGWq\
totalPage = totalRecords / everyPage; &FD>&WRV
else iB{V^ksU
totalPage = totalRecords / everyPage + 1 ; fIF8%J ^3
7 3m1
return totalPage; $^P0F9~0
} ZW}_DT0
8_8l.!~
privatestaticboolean hasPrePage(int currentPage){ =Uh$&m
return currentPage == 1 ? false : true; xA/D'
} L$-T,Kze
9gFUaDLo
privatestaticboolean hasNextPage(int currentPage, $?Wb}DU7_L
G2Zer=rC
int totalPage){ *or(1DXP8
return currentPage == totalPage || totalPage == TNth
+0~YP*I`/
0 ? false : true; 2|L&DF:G
} Y7aqO5
/NlGFO*Z
yw!{MO
} 2?5>o!C
Qd-A.{[h
$k?>DP4
Y}/-C3)
P%6~&woF
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 :
'c&,oLY
xmG<]WF>E
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 {FGj]*
yLGRi^d#
做法如下: N$DkX)Z
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 *Uh!>Iv;
RpK@?[4s
的信息,和一个结果集List: sRW<me;
java代码: K8~d^G
y^k$Us
/,dz@
/*Created on 2005-6-13*/ 8QK&_n*
package com.adt.bo; S:Hl/:iV
<UI
[%yXj
import java.util.List; <[phnU^
8
s S
Mh`4'
import org.flyware.util.page.Page; (ZGbhMK
<Uur^uB
/** y(&Ac[foS}
* @author Joa 6mE\OS-I
*/ >Q/Dk7 #
publicclass Result { VQs5"K"
[e
q&C_|D
private Page page; GeqPRah
:Al!1BJQ
private List content; 2|,VqVb
DqPw#<"H
/** !<oe=)Iz|
* The default constructor TseGXYH
*/ ~@!bsLSMU
public Result(){ I|OoRq
super(); 92c HwWZ!
} T+$[eWk"a
B[}6-2<>?C
/** H.;Q+A,8^
* The constructor using fields pw#-_
* @L`jk+Y0vF
* @param page K'xV;r7Nt
* @param content S@Y39
*/ 7nSxi+6e
public Result(Page page, List content){ fOHxtHM
this.page = page; 5N]"~w*
this.content = content; 9^x> 3Bo
} UBs4K*h|
QnDg6m)+
/** i@q&5;%%
* @return Returns the content. )_:NLo:
*/ =%7-ZH9
publicList getContent(){ ~rm_vo
return content; /xQTxh1;K
} NRuNKl.v
TrNF=x>
/** o4;(Zi#Z
* @return Returns the page. g7|@
*/ uNyVf7u
public Page getPage(){ ni<(K
0~
return page; %xW"!WbJ|
} YR70BOxK
Smh,zCc>s
/** vI?, 47Hj+
* @param content 7^Uv7<pw
* The content to set. SJLis"8
*/ 7=uj2.J6
public void setContent(List content){ JT?h1v<H]
this.content = content; WA qINLdX
} _g8yDfcLG
^Pf WG*
/**
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* @param page AX INThJ
* The page to set. ]|@^1we
*/ "4Nt\WQ
publicvoid setPage(Page page){ +_!QSU,@
this.page = page; ~Ei<Z`3}7"
} + 3gp%`c4
} =wJX0A|
iscz}E,Y
#Z #-Ht
]GS bjHsO
UG^q9 :t
2. 编写业务逻辑接口,并实现它(UserManager, Wqnc{oq|$
Sz~OX6L
UserManagerImpl) `L
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java代码: wzA$'+Mb
[^)g%|W
OI*H,Z"
/*Created on 2005-7-15*/
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package com.adt.service; dr(*T
m 5.Zu.
import net.sf.hibernate.HibernateException; "%_+-C<L4
]'cs.
import org.flyware.util.page.Page; gR**@t=;j
DXo|.!P=3
import com.adt.bo.Result; #E?4E1bnB
%>yL1BeA4
/** \+etCo
* @author Joa M:8R-c#![
*/ `uFdwO'DD
publicinterface UserManager { {ax:RUQxy
wJ]d&::@h
public Result listUser(Page page)throws oDR%\VY6T
^~dWU>
HibernateException; x:;kSh
Q8NX)R
} e(sk[guvX
bOB\--:]
_#niyW+?~
do%&m]#;
a[C@
java代码: KXy6Eno
$`c:&
j.Hf/vi`z
/*Created on 2005-7-15*/ +0&/g&a\R
package com.adt.service.impl; osRy e3
2T35{Q!=F
import java.util.List; eavV?\uV%
. vV|hSc
import net.sf.hibernate.HibernateException; |=w@H]r
f 2.HF@
import org.flyware.util.page.Page; q'DW~!>qX
import org.flyware.util.page.PageUtil; BLttb
R5D1w+
import com.adt.bo.Result; XUYtEf
import com.adt.dao.UserDAO; pkzaNY/q
import com.adt.exception.ObjectNotFoundException; x4 yR8n(
import com.adt.service.UserManager; pb}*\/s
\bcLiKE{
/** KwS@D9bok
* @author Joa tc! #wd+u
*/ uYN`:b8
publicclass UserManagerImpl implements UserManager { n[z+<VGwC
vgPCQO([
private UserDAO userDAO; sT)CxOV
m@c)Xci
/** rH-23S
* @param userDAO The userDAO to set. NOva'qk
*/ %Zi} MPx
publicvoid setUserDAO(UserDAO userDAO){ $I=~S[p
this.userDAO = userDAO; nKY6[|!#
} xEI%D|)<
;`&kZi60Hz
/* (non-Javadoc) YWLj?+
* @see com.adt.service.UserManager#listUser wp_0+$?s
Upe%rC(
(org.flyware.util.page.Page) u_enqC3
*/ b;n[mk
public Result listUser(Page page)throws J zl6eo[;
,F|f. 7;
HibernateException, ObjectNotFoundException { p2eGm-Erq
int totalRecords = userDAO.getUserCount(); }tz7b#
if(totalRecords == 0) [WmM6UEVS
throw new ObjectNotFoundException icgfB-1|i
uFE)17E
("userNotExist"); z_HdISy0
page = PageUtil.createPage(page, totalRecords); 3w=J'(RU
List users = userDAO.getUserByPage(page); 1#x0 q:6
returnnew Result(page, users); F%|h;+5
} mt
.sucT
}7Uoh(d
} lN@o2QX
f#;> g
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:X=hQ:>P
V88p;K$+
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 m`XHKRp
,bi^P>X
询,接下来编写UserDAO的代码:
P0@,fd<
3. UserDAO 和 UserDAOImpl: TbU#96"~.
java代码: 4 KiY6)
(=0.in Z
~$'awY
/*Created on 2005-7-15*/ ;l+Leex
package com.adt.dao; # d
Vr}'.\$
import java.util.List; l#o
~W`
.A|udZ,
import org.flyware.util.page.Page; )5,v!X)
7#XzrT]
import net.sf.hibernate.HibernateException; {c'lhUB
4Z*/WsCv
/** )7F/O3Tq
* @author Joa 4RO}<$Nx}
*/ 4s-!7
publicinterface UserDAO extends BaseDAO { e
,(mR+a8
sC'`~}C
publicList getUserByName(String name)throws G{}VPcrbC
@JMiO^
HibernateException; fhiM U8(&
V
gWRW7Se
publicint getUserCount()throws HibernateException; {)XTk&"
79gT+~z
publicList getUserByPage(Page page)throws N8jIMb'<
Cdn J&N{
HibernateException; k[xSbs'D
HPl<%%TI
} pBHRa?Y5
x5Bk/e'
3og.y+.=U.
[txE .7p
j#|ZP-=1_
java代码: -@'FW*b
q9"96({\@
i1UsIT
/*Created on 2005-7-15*/ e'~3oqSvR
package com.adt.dao.impl; Q,g\
E GU2fA7x
import java.util.List; ytImB`'\
?<!|
import org.flyware.util.page.Page; oH@78D0A
|yCMt:Hk
import net.sf.hibernate.HibernateException; 6k%f
import net.sf.hibernate.Query; e~OpofJNb
:WEDAFq0
import com.adt.dao.UserDAO; C|bET
>4TO=i
/** i-1op> Y
* @author Joa `5*}p#G
*/ sHj/;
public class UserDAOImpl extends BaseDAOHibernateImpl 1MFbQs^
-).C
implements UserDAO { )0`C@um
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/* (non-Javadoc) .-zom~N-?
* @see com.adt.dao.UserDAO#getUserByName &oNAv-m^GD
Rq -ZL{LR7
(java.lang.String) -"x$ZnHU
*/ 203s^K61
publicList getUserByName(String name)throws
mh%VrAq
z{q`G wW
HibernateException { KI.unP%
String querySentence = "FROM user in class *. t^MP
W?&%x(6M
com.adt.po.User WHERE user.name=:name"; tQVVhXQ7
Query query = getSession().createQuery @7}W=HB
}>\C{ClI
(querySentence); kh<2BOV
query.setParameter("name", name); ctQ/wrkU
return query.list(); :FF=a3/"6
} 4euO1=
u8^lB7!e/
/* (non-Javadoc)
7GGUV
* @see com.adt.dao.UserDAO#getUserCount() (Ld i|jL
*/ Iu{V,U
publicint getUserCount()throws HibernateException { @ Qe0! (_=
int count = 0; btB%[]
String querySentence = "SELECT count(*) FROM 9c],<;{'
S:}7q2:
user in class com.adt.po.User"; +T ?NH9
Query query = getSession().createQuery 'u658Tj
st*gs-8jJ;
(querySentence); c-w)|-ac.
count = ((Integer)query.iterate().next >_}
I.\X
]e3Ax(i)
()).intValue(); DG/Pb)%Y
return count; okXl8&mi
} 9WHddDA
gw(z1L5
n
/* (non-Javadoc) K3C <{#r
* @see com.adt.dao.UserDAO#getUserByPage kfNWI#'9
f1? >h\F8
(org.flyware.util.page.Page) WIOV2+
*/ ICCc./l|
publicList getUserByPage(Page page)throws M5B# TAybC
zs;JJk^
HibernateException { a*;b^Ze`v
String querySentence = "FROM user in class (H]AR8%W
yZ:qU({KhD
com.adt.po.User"; iso4]>LF
Query query = getSession().createQuery @HW*09TG
Efe 7gE'
(querySentence); & kIFcd@
query.setFirstResult(page.getBeginIndex()) :&Nbw
.setMaxResults(page.getEveryPage()); p_ =z#
return query.list(); AW .F3hN)
} 0:+E-^X
DI vHvFss
} i4Jc.8^9$
oU|c.mYe
b6[j%(
}G=M2V<L
9L9sqZUB
至此,一个完整的分页程序完成。前台的只需要调用 TC. ,V_
(hsl~Jf
userManager.listUser(page)即可得到一个Page对象和结果集对象 )"LJ
hLg
m|# y
>4
的综合体,而传入的参数page对象则可以由前台传入,如果用 NI5``BwpO
n%-0V>
webwork,甚至可以直接在配置文件中指定。 E]6
6]+;0_
Bx!-"e
下面给出一个webwork调用示例: _@g;8CA
java代码: tkhCw/
!wNO8;(
l2d{ 73h
/*Created on 2005-6-17*/ ToQ"Iy?
package com.adt.action.user; u-TUuP
wzaV;ac4K
import java.util.List; ,Q,^3*HX9}
Q?T]MUY(L
import org.apache.commons.logging.Log; hph4 `{T
import org.apache.commons.logging.LogFactory; Al'3?
import org.flyware.util.page.Page; >7r!~+B"9'
,[Fb[#Qqb
import com.adt.bo.Result; u>$t'
import com.adt.service.UserService; t5zKW _J7
import com.opensymphony.xwork.Action; %SI'BJ
4YHY7J
/** z2c6T.1M
* @author Joa DJir { \F
*/ P4?glh q#
publicclass ListUser implementsAction{ ddo#P%sH'
8Y3I0S
privatestaticfinal Log logger = LogFactory.getLog &~!Wym
}%z
(ListUser.class); aT<q=DO
t
Pf40`@
private UserService userService; $cR{o#
i!cCMh8
private Page page; p7Cs.2>M>S
yNc2@
privateList users; KG@8RtHsQ
&{RDM~
/* G
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* (non-Javadoc) ;]fs'LH
* C7vxw-o|&p
* @see com.opensymphony.xwork.Action#execute() !c-*O<Y
*/ fV:83|eQ
publicString execute()throwsException{ .o8t+X'G
Result result = userService.listUser(page); &R siVBA
page = result.getPage(); q =Il|Nb>
users = result.getContent(); H[UlY?&+
return SUCCESS; w*!aZ,P
} ExM,g' 7
!+ njS
/** DJ%PWlK5
* @return Returns the page. h$=2 p5'-
*/ l]cFqLp
public Page getPage(){ TKjFp%
return page;
9akH
} x :7IIvP
{|\.i
/** xCKRxF
* @return Returns the users. X@f}Q`{Ymj
*/ v}(WaO#S
publicList getUsers(){ mqJ_W[y7
return users; >f'g0g
} &/b~k3{M_
%bfZn9_m
/** rs.M]8a2{&
* @param page 6^Sa;
* The page to set. XlJZhc
*/ \?N2=jsu$
publicvoid setPage(Page page){ - YV>j
this.page = page; .mAjfP*
} }&e5$lB
Z6pUZ[j,
/** Bj~+WwD)QR
* @param users 8Eq7Sa
* The users to set. !Uc T RI
*/ VD :/PL
publicvoid setUsers(List users){ qCO/?kW
this.users = users; 0;ji65
} C-[1iW'
tl].r|yl
/** ;>YzEo
* @param userService
BB'OCN
* The userService to set. !a<ng&H^U
*/ H.2QKws^F
publicvoid setUserService(UserService userService){ J$!iq|
this.userService = userService; '{`$#@a.
} $kKjgQS(
} eY\yE"3
f9;(C4+
xvy.=(
}{"fJ3] c^
QIgNsz
上面的代码似乎看不出什么地方设置了page的相关初值,事实上, _[y/Y\{I
8*fv'
可以通过配置文件来进行配置,例如,我想每页显示10条记录,那 kwA$Z!Rn
{GO#.P"
么只需要: +{UcspqM
java代码: x;')9/3
qv*^fiT
e]tDy0@
<?xml version="1.0"?> h@h! ,;
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork 2Gdd*=4z
n}V_,:Z
1.0//EN" "http://www.opensymphony.com/xwork/xwork- `KQvJjA6
4H-'Dr=G
1.0.dtd"> Tqk\XILG N
iyp=lLk
<xwork> F\KUZ[%
LDg?'y;2
<package name="user" extends="webwork- LrK,_)r:~
6DWgl$[[
interceptors"> [h:T*(R?
]d%8k}U
<!-- The default interceptor stack name +H
Usz?
"}JZU!?
--> 6x|jPb
<default-interceptor-ref $j?1g#
~!3r&(
name="myDefaultWebStack"/> PzR[KUK
9$m|'$p3sG
<action name="listUser" C/&-l{7
,=mS,r7
class="com.adt.action.user.ListUser"> D )'bH5
<param TW>WHCAm
*|E[L^
name="page.everyPage">10</param> XS BA$y
<result uOGw9O-d9
ilva,WFa^
name="success">/user/user_list.jsp</result> fg{n(TE"8
</action> X~i<g?]
hiw|2Y&`
</package> 6Kb1~jY
I)W`sBL
</xwork> Lu0x
(/
F*K_+
?m
_\HQvH
7`hP?a=
=6#Eh=7N
IyPnp&_
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 F.v{-8GV
1&o|TT/
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。 !7&5` q7
V,?yPi$#E
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 -FlzEZ
"2T#MO/
bnLPlf
7(
2{'r
Y7[jqb1D
我写的一个用于分页的类,用了泛型了,hoho -\n@%$M]G
'oC)
NpnH
java代码: _H=Uwi_g
~BkCp pI
$"&{aa
package com.intokr.util; BFJnV.0M!
[R7Y}k:9U
import java.util.List; ~**.|%Kc
'-/xyAzS
/** [=^3n#WW
* 用于分页的类<br> aCLq k'
* 可以用于传递查询的结果也可以用于传送查询的参数<br> mju>>\9
* fe#\TNeQJ[
* @version 0.01 D+7Rz_=
* @author cheng q=qcm`ce
*/ }<y7bqA
public class Paginator<E> { @[i4^
privateint count = 0; // 总记录数 5RpjN: 3
privateint p = 1; // 页编号 3gj+%%!G\
privateint num = 20; // 每页的记录数 ;?g6QIN9
privateList<E> results = null; // 结果 ^Zy%fv,
^B2
-)
/** klR|6u]%
* 结果总数 fLm*1S|%\
*/ Zdo'{ $
publicint getCount(){ HuKc9U'7A
return count; k/gZ,
} B[?CbU
Y,e B|
publicvoid setCount(int count){ 0|\$Vp
this.count = count; Y.ToIka{
} A^EE32kbm
yw3$2EW
/** Y<ql49-X
* 本结果所在的页码,从1开始 ;x1PS
* ; XN{x
* @return Returns the pageNo. :7?FF'u
*/ 4u47D$=
publicint getP(){ ["e3Ez
return p; 2q4<t:!
} =-lb)Z"d
@\P;W(m.i
/** 6ez<g
Uf
* if(p<=0) p=1 W$2C47i
* 3+fp2
* @param p hJ#xB6
*/ D^3vr2
publicvoid setP(int p){ e?ly H
if(p <= 0) r7,t";?>
p = 1; Ev(>z-{F
this.p = p; 'B0{_RaTb
} fG(SNNl+D
TNh1hhJ$b
/** #PQB(=299P
* 每页记录数量 GMl;7?RA
*/ - kwXvYu\
publicint getNum(){ _ T):G6C8
return num; oVe|Mss6
} Zt.|oYH$
8- %TC\:
/** sCb=5uI
* if(num<1) num=1 =k0_eX0
*/ xzZ38xIhV
publicvoid setNum(int num){ o;R2p $
if(num < 1) P8)=Kbd
num = 1; j*jo@N|
this.num = num; }\:NuTf
} qd)/9*|Jl
xZwLlY
/** hUMf"=q+
* 获得总页数 %pd ,%pg
*/ A/KJqiag
publicint getPageNum(){ qC:raH_:
return(count - 1) / num + 1; QTXt8I
} 4X
|(5q?
os={PQRD
/** DOJ N2{IP
* 获得本页的开始编号,为 (p-1)*num+1 '>0fWBs
*/ <drODjB
publicint getStart(){ \EtQ5T*u
return(p - 1) * num + 1; a^zibPG
} sCk?
XkF%.hWo
/** s<eb;Z2D
* @return Returns the results. 91g2A|
*/ (l-ab2'
publicList<E> getResults(){ UsQ+`\|
return results; ;J2z p*|
} ssRbhlD/*1
E:}r5S)4
public void setResults(List<E> results){ CtAwBQO
this.results = results; u5: q$P
} /qGf 1MHD
n}G|/v<
public String toString(){ FZ,#0ZYJGP
StringBuilder buff = new StringBuilder D9
|n)f
MET' (m
(); $79=lEn,
buff.append("{"); iQ
fJ
buff.append("count:").append(count); C3],n
buff.append(",p:").append(p); ~SF<,-Kg
buff.append(",nump:").append(num); SY^t} A7:/
buff.append(",results:").append 7KL v6]b
R:k5QD9/&p
(results); N@1+O,o
buff.append("}"); z>Hgkp8D"
return buff.toString(); $gy*D7
} X4E%2-m@'
a8iQ4
} uPG4V2
2fR02={-
2Mmz %S'd