Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 1vu4}%nD
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 XJ]MPiXj
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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 Cc]s94
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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 ^ h^2='p
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分页支持类: 8N(bLGUG
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java代码: 0|{U"\
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package com.javaeye.common.util; NV;5T3
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import java.util.List; z$-/yT"M
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publicclass PaginationSupport { %kJ:{J+w]
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publicfinalstaticint PAGESIZE = 30; P1
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privateint pageSize = PAGESIZE; P,iLqat
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privateList items; *@G4i
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privateint totalCount; #X"\:yN
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privateint[] indexes = newint[0]; @D"#B@j
q) /;|h
privateint startIndex = 0; %8$JL=c
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public PaginationSupport(List items, int \\hZlCV,
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totalCount){ -5vc0"?E
setPageSize(PAGESIZE); o^&;
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setTotalCount(totalCount); N,'JQch},8
setItems(items); I2j;9Qcz
setStartIndex(0); #jr;.;8sQ
} S97.O@V!$
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public PaginationSupport(List items, int 9qXHdpb#g"
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totalCount, int startIndex){ q9WdJ!-^X
setPageSize(PAGESIZE); RO wbzA)]r
setTotalCount(totalCount); l,*Q?q
setItems(items); >Fx$Rty
setStartIndex(startIndex); 8<!qT1
} #A]7cMZ'W
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public PaginationSupport(List items, int (^a;2j9
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totalCount, int pageSize, int startIndex){ a4`@z:l
setPageSize(pageSize); 7R))(-
setTotalCount(totalCount); bvG").8$
setItems(items); &v4w3'@1
setStartIndex(startIndex); #yr19i ?
} $o]zNW;X
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publicList getItems(){ CM5A-R90
return items; A$XjzTR
} Q=PaTh
mZ/B:)_
publicvoid setItems(List items){ 1LPfn(
this.items = items; 'b661,+d
} yH#;k:O=
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publicint getPageSize(){ Fa+PN9M`?.
return pageSize; =53LapTPJ
} 3<mv9U(
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publicvoid setPageSize(int pageSize){ @/$mZ]|T
this.pageSize = pageSize; F|P2\SPL
} 1v2wP2]|;
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publicint getTotalCount(){ g=U?{<8.m
return totalCount; [7I|8
} P< WD_W
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V^
publicvoid setTotalCount(int totalCount){ >P0AGZ
if(totalCount > 0){ _a<PUdP
this.totalCount = totalCount; /0o 2
int count = totalCount / Plq[Ml9
y'@l,MN{
pageSize; -|)[s[T~m
if(totalCount % pageSize > 0) FJ U)AjS~
count++; ^w&TTo(
indexes = newint[count]; lZ)u4_
for(int i = 0; i < count; i++){ Z,4=<;PF
indexes = pageSize * t91CxZQ^s
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i; LWQ BGiJj
} [qZ4+xF,,
}else{ HqF8:z?v
this.totalCount = 0; v Q_ B2#U:
} }SN'*w@E
} oTa! F;I
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publicint[] getIndexes(){ +]
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return indexes; _r8AO>
} \clWrK
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publicvoid setIndexes(int[] indexes){ rk. UW
this.indexes = indexes; NXmj<azED
} teB{GR
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publicint getStartIndex(){ X4k/7EA
return startIndex; =VY4y]V
} \!^o<$s.G
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publicvoid setStartIndex(int startIndex){ C|lMXp\*
if(totalCount <= 0) AQV3ZVP
this.startIndex = 0; ncA2en?
elseif(startIndex >= totalCount) hT]p8m
aRZ
this.startIndex = indexes M^[jA](a
qt:->yiq+
[indexes.length - 1]; Wey\GQ`"8
elseif(startIndex < 0) A!Yqj~
this.startIndex = 0; eoL)gIM%
else{ ttKfZ0
this.startIndex = indexes #-f^;=7
5-3gsy/Mo
[startIndex / pageSize]; ^7''x,I
} U)PumU+z$u
} 0Gs]>B4r/
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publicint getNextIndex(){ <n:?WP~U
int nextIndex = getStartIndex() + \c\=S
y]+A7|
pageSize; GbE3:;JI
if(nextIndex >= totalCount) .Lp-'!i
return getStartIndex(); e=R}
4`
else dog,vUu
return nextIndex; <5#e.w
} :_H88/?RR
*&PgDAQ
publicint getPreviousIndex(){ UetmO`qju
int previousIndex = getStartIndex() - zSH#j RDV
kj#yG"3+
pageSize; Lf:Z
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if(previousIndex < 0) b7,qzh
return0; 0IdD
else avz 4&
return previousIndex; Iymz2
} evR= Z\
_
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} qXF"1f_+
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抽象业务类 zKutx6=aj
java代码: hf-S6PEsM
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/** 1_QO>T'
* Created on 2005-7-12 :h3JDQe:.
*/ p(8\w-6
package com.javaeye.common.business; :Rn9rdX
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import java.io.Serializable; wf4Q}l2,d
import java.util.List; F)IP~BE-k
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import org.hibernate.Criteria; A^7!+1*K+
import org.hibernate.HibernateException; 6{~I7!m"
import org.hibernate.Session; d]^i1
import org.hibernate.criterion.DetachedCriteria; ;@
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import org.hibernate.criterion.Projections; O`=Uq0Vv
import Pm_=
%Fv)$ :b
org.springframework.orm.hibernate3.HibernateCallback; #? *jdN:
import d0^2<
?xet:#R'
org.springframework.orm.hibernate3.support.HibernateDaoS Txh;r.1e
jZ;T&s
upport; 3:(`#YY
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import com.javaeye.common.util.PaginationSupport; zyr6Tv61U
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public abstract class AbstractManager extends 24Fxx9g
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HibernateDaoSupport { 'FhnSNT(4=
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privateboolean cacheQueries = false; 'zb7:[[7%
]*|K8&jxl
privateString queryCacheRegion; ||4Dtg
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publicvoid setCacheQueries(boolean * y B-N;I
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cacheQueries){ &g!/@*[Nhh
this.cacheQueries = cacheQueries; :]s] =q&]
} M@\'Y$)Y{
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publicvoid setQueryCacheRegion(String OOCeZ3yF(
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queryCacheRegion){ 2YyZiOMSc
this.queryCacheRegion = d#\n)eGr
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queryCacheRegion; >g&`g}xZQ
} +*V;
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publicvoid save(finalObject entity){ :dzU]pk%0
getHibernateTemplate().save(entity); +0 MKh
} u_BSWhiW
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publicvoid persist(finalObject entity){ W<Lrfo&=Y]
getHibernateTemplate().save(entity); g$b*#
} .IXwa,
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publicvoid update(finalObject entity){ 4_<Uk
getHibernateTemplate().update(entity); * 5n:+Tw(
} J%)2,szn0
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publicvoid delete(finalObject entity){
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getHibernateTemplate().delete(entity); l5FQ!>IM
} {76!
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}
publicObject load(finalClass entity, [/G;XHL;?
7,TWCVap
finalSerializable id){ ~|rkt`8p
return getHibernateTemplate().load jGn^<T\
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(entity, id); 0, /x#
} 3U)8P6Fz
}El_.@'T &
publicObject get(finalClass entity, !U_L7
cy 4'q?r
finalSerializable id){ Pc'?p
return getHibernateTemplate().get N+5^h(~
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(entity, id); >9`ep7
} m+vEs,W.
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publicList findAll(finalClass entity){ >{a,]q*
return getHibernateTemplate().find("from )*ckJK
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" + entity.getName()); Q\L5ZJ%y/
} Br5Io=/wg
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publicList findByNamedQuery(finalString gf?^yP ;V
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namedQuery){ : qRT9n$
return getHibernateTemplate P~e$iBH'
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().findByNamedQuery(namedQuery); LltguNM$
} pm\X*t}L
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publicList findByNamedQuery(finalString query, or}*tSKX
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finalObject parameter){ :N*T2mP
return getHibernateTemplate =joXP$n^
j_@3a)[NY
().findByNamedQuery(query, parameter); K"7;Y#1g
} K/`RZ!
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publicList findByNamedQuery(finalString query, RFY!o<
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finalObject[] parameters){ sG2 3[t8
return getHibernateTemplate 5Q` n6 x|
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().findByNamedQuery(query, parameters); N?0y<S ?!
} C+XZDY(=Z
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publicList find(finalString query){ RH]>>tJ^e
return getHibernateTemplate().find *]R0z|MW
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(query); mndl~/
} l-}5@D[
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publicList find(finalString query, finalObject I^(#\vRW
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parameter){ @T1+b"TC
return getHibernateTemplate().find ?3TV:fx"X
?VQLY=?
(query, parameter); c8tC3CrKp=
} h;qy5KS
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public PaginationSupport findPageByCriteria h6y4Ii
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(final DetachedCriteria detachedCriteria){ n~u3
return findPageByCriteria J+jmSK%z
ih |Ky+ !
(detachedCriteria, PaginationSupport.PAGESIZE, 0); e=sJMzm~
} F*t_lN5{
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public PaginationSupport findPageByCriteria
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@B[Cc`IN"
(final DetachedCriteria detachedCriteria, finalint l/zC##1+.
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startIndex){ zL`uiZl
return findPageByCriteria `(/saq*
(0#F]""\e
(detachedCriteria, PaginationSupport.PAGESIZE, =4<S8Cp
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startIndex); ;c
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} aroVyUs3j
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public PaginationSupport findPageByCriteria &4&33D
.#55u+d,
(final DetachedCriteria detachedCriteria, finalint [Am`5&J
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pageSize, )S}; k=kG
finalint startIndex){ ?7MwTi8{F
return(PaginationSupport) tQ/
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getHibernateTemplate().execute(new HibernateCallback(){ a`b zFu{
publicObject doInHibernate E? eWv)//
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(Session session)throws HibernateException { <o!&Kk 9
Criteria criteria = Secq^#]8
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detachedCriteria.getExecutableCriteria(session); S=H_9io
int totalCount = @D~+D@i$TW
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((Integer) criteria.setProjection(Projections.rowCount ~,*YmB=Z
)R8%'X;U
()).uniqueResult()).intValue(); #3K,V8(
criteria.setProjection
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(null); g(1B W#$
List items = 4s~HfxYT
#CA%]*l*F
criteria.setFirstResult(startIndex).setMaxResults >$naTSJq
4[#6<Ixf
(pageSize).list(); \}Acq;
PaginationSupport ps = poQdI?ed,
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new PaginationSupport(items, totalCount, pageSize, 9#&W!f*qO|
a WeBav}_
startIndex); }\f(qw
return ps; =^Sw*[eiy
} O5qW*r'
}, true); u-QO>3oY6
} 2zKo
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public List findAllByCriteria(final Yn4)Zhkk
,<$YVXe/
DetachedCriteria detachedCriteria){ #PslrA.
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return(List) getHibernateTemplate ]A]Ft!`6z
n^AP"1l8?0
().execute(new HibernateCallback(){ 7"F|6JP"$c
publicObject doInHibernate 4W!\4Va
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(Session session)throws HibernateException { -jxWlO
Criteria criteria = _}zo
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detachedCriteria.getExecutableCriteria(session); gX$0[
sIS.
return criteria.list(); qcTmsMpj
} c.(Ud`jc
}, true); ZD)0P=%
} J3~hzgY
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public int getCountByCriteria(final Jh$"f r3
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DetachedCriteria detachedCriteria){ 1Y=AT!"V
Integer count = (Integer) <AMb!?Obh
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getHibernateTemplate().execute(new HibernateCallback(){ -@SOo"P
publicObject doInHibernate <TR/ `
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(Session session)throws HibernateException { #9$V
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Criteria criteria = +ze}0lrEL
CF|moc:;
detachedCriteria.getExecutableCriteria(session); m<4s*q0\i
return V$dJmKg
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criteria.setProjection(Projections.rowCount =[P%_v``
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()).uniqueResult(); @PQrmn6w
} 5S%C~iB
}, true); D3S+LV
return count.intValue(); -9OMn}w/*
} (Qk&g"I
} As@ihB+(\
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用户在web层构造查询条件detachedCriteria,和可选的 vWU%ST
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 +_qh)HX
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PaginationSupport的实例ps。 H\^VqNK"
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ps.getItems()得到已分页好的结果集 -3.UE^W2
ps.getIndexes()得到分页索引的数组 61/)l0<;
ps.getTotalCount()得到总结果数 rH9uGm-*
ps.getStartIndex()当前分页索引 h?0F-6z
ps.getNextIndex()下一页索引 g1ZV&X=2
ps.getPreviousIndex()上一页索引 Abj97S
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 8f?rEI\0GD
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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 hPan
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一下代码重构了。 nQ5N=l
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我把原本我的做法也提供出来供大家讨论吧: Rl_.;?v"!
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首先,为了实现分页查询,我封装了一个Page类: /61by$E
java代码: LGIalf*7
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/*Created on 2005-4-14*/ 2;:lK" :
package org.flyware.util.page; {Q)dU-\
^:qD .h>&
/** NMXnrvS&
* @author Joa hUVk54~l
* i{8]'fM
*/ 16I&7=S,
publicclass Page { %=V" CJ$|
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/** imply if the page has previous page */ ?VB#GJ0M9
privateboolean hasPrePage; s=MT,
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cG[W3
/** imply if the page has next page */ \a"i7Caa
privateboolean hasNextPage; oEJaH
*p=fi
/** the number of every page */ RI-A"cc6A
privateint everyPage; 7_DG 5nT
D!oZ?dGCo6
/** the total page number */ i;c'P}[K
privateint totalPage; Pg/T^n&
-'6<
/** the number of current page */ q]px(
privateint currentPage; lR:?uZ$
{>@QJlE0
/** the begin index of the records by the current Y
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SSE3tcRRl
query */ pprejUR
privateint beginIndex; czI{qi5N
mj@31YW
n@
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/** The default constructor */ 4r\*@rq
public Page(){ eOt%x Tx
Jen%}\
} PWvSbn6
Vvyj
/** construct the page by everyPage QC{u|
* @param everyPage |8H_-n
* */ U;g S[8,p
public Page(int everyPage){ *(G&B\
this.everyPage = everyPage; ahA{B1M)n
} -0$:|p?@^
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/** The whole constructor */ ;K_}A4K
public Page(boolean hasPrePage, boolean hasNextPage, JWWYVl VC
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3?2<WEYr
int everyPage, int totalPage, ?q_^Rj$
int currentPage, int beginIndex){ zG#wu
this.hasPrePage = hasPrePage; Q&xjF@I
this.hasNextPage = hasNextPage; zsDocR
this.everyPage = everyPage; daslaa_A
this.totalPage = totalPage; MTb,Kmw<(
this.currentPage = currentPage; 1AF%-<`?s
this.beginIndex = beginIndex; } B0sC%cm
} d ;^
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/** &~ *.CQa
* @return k#C
f})
* Returns the beginIndex. Q".g.k
*/ =q+R
publicint getBeginIndex(){ 1a$IrQE
return beginIndex; :=<0=JE#
} Q(Gyq:L=>
([R")~`(l2
/** _({@B`N}
* @param beginIndex $W&:(&
* The beginIndex to set. zBY~lNB
*/ t<63 8`{kk
publicvoid setBeginIndex(int beginIndex){ M+poB+K.
this.beginIndex = beginIndex; <~{du ?4n
} *%\mZ,s"
S/4r\6
/** 8[zb{PRu
* @return Kb&V!#o)
* Returns the currentPage. dU]/$7
*/ R>2I RvY(
publicint getCurrentPage(){ eY,O@'"8`
return currentPage; ?59'dGnz_
} Zw{MgoJ0Z
M0L&~p_F
/** sN~ \+_
* @param currentPage 8#X_#
* The currentPage to set. PLA#!$c7q
*/ _c2WqQ-05
publicvoid setCurrentPage(int currentPage){ m\ S\3n
this.currentPage = currentPage; JoZ(_Jh%m
} *fnvZw?
$dQIs:
/** mR%FqaN_
* @return }D*yr3b
* Returns the everyPage. T\9~<"P^
*/ WO X}Sw"
publicint getEveryPage(){ z.oU4c
return everyPage; .[:VSM7T
} 8{0k0 &x
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/** %S@L|t
* @param everyPage tY+$$GSQj
* The everyPage to set. hmC*^"C>U=
*/ lnh+a7a)
publicvoid setEveryPage(int everyPage){ 'yY>as
this.everyPage = everyPage; '<dgT&8C
} R)5n 8
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/** epg#HNP7^Y
* @return J !HjeZ
* Returns the hasNextPage. L',mKOej
*/ ,Na^%A@TJ
publicboolean getHasNextPage(){ i"r!w|j
return hasNextPage; 65TfFcQ<S
} &GhPvrxI?
CnISe^h
/** uw AwWgl
* @param hasNextPage Ps4 ZFX
* The hasNextPage to set. wN=;i#
*/ S($Su7g%_
publicvoid setHasNextPage(boolean hasNextPage){ 0 1V^L}
this.hasNextPage = hasNextPage; Y32 "N[yw
} R=]d%L8
M.q=p[
/** a5jL7a?6]
* @return J00VTb`
* Returns the hasPrePage. F$V/K&&W
*/ !do?~$Og
publicboolean getHasPrePage(){ hK|j6xf.o
return hasPrePage; #%lo;W~IY
} YA:nOvd@O
o0bM=njok
/** 5!X1G8h)uy
* @param hasPrePage O|kOI?f
* The hasPrePage to set. 9?<{_'
*/ K`g7$r)U[
publicvoid setHasPrePage(boolean hasPrePage){ 3g~'5Ao
this.hasPrePage = hasPrePage; _S}A=hK'
} 5PT5#[
k8AW6oO/i
/** n'1'!J;Q
* @return Returns the totalPage. PcT?<HU
* _hu")os
*/ 8s{?v&p
publicint getTotalPage(){ QXgE
dsw
return totalPage; )wvHGecp*
} #OO>rm$
<h-vjz
/** iB[~U3
* @param totalPage LJ)5W
* The totalPage to set. 7!WA)@6
*/ Om;&_!i
publicvoid setTotalPage(int totalPage){ !%)F J:p
this.totalPage = totalPage; |yEa5rd?W
} BZ54*\t
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} gKYfQ+
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-i yyn^|
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f y:,_#
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 myl+J;,]
+ZM)bbB
个PageUtil,负责对Page对象进行构造: Qv,"($n\
java代码: ?']5dD
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/*Created on 2005-4-14*/ i0$Bx>
package org.flyware.util.page; Q/>{f0
E:9"cxx
import org.apache.commons.logging.Log; #S&Tkip]"W
import org.apache.commons.logging.LogFactory; /DQaGq/Ld
2'EUy@0
/** jB{4\)
* @author Joa hd),&qoW?
* ( +pLA"xq
*/ n!p<A.O7@
publicclass PageUtil { AP77a*@8
{M-YHX>*;g
privatestaticfinal Log logger = LogFactory.getLog ?HF%(>M
S}p4iE"n
(PageUtil.class); s<qe,'Y
+gtrt^:]l
/** <:SZAAoIV
* Use the origin page to create a new page ={K`4BD
* @param page 'Vyt4^$%
* @param totalRecords o(DOQ Gl
* @return h 3]wL.V
*/ I)A`)5="5
publicstatic Page createPage(Page page, int n2)q}_d
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totalRecords){ fFb_J`'ue
return createPage(page.getEveryPage(), 3;S,3
[0"'T[ok
page.getCurrentPage(), totalRecords); Llr>9(|
} +qh[N@F
Ut2y;2)a
/** H,Z;=N_
* the basic page utils not including exception r E}%KsZ
Jn{OWw2
handler .C 8PitS
* @param everyPage
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* @param currentPage B!vmQR*1
* @param totalRecords IiY/(N+J
* @return page dZi"$ g
*/ Z?wU
publicstatic Page createPage(int everyPage, int e,t(q(L
(M*FIX
currentPage, int totalRecords){ U}[I
everyPage = getEveryPage(everyPage); 5$V_Hj
currentPage = getCurrentPage(currentPage); ^h69Kr#d4
int beginIndex = getBeginIndex(everyPage, 0NS<?p~_S
j#cYS*^H
currentPage); N[s}qmPha
int totalPage = getTotalPage(everyPage, -$\+'
\
b )B?
F
totalRecords); {q"OM*L(
boolean hasNextPage = hasNextPage(currentPage, zT!drq: x
W[Ls|<Q
totalPage); {phNds%
boolean hasPrePage = hasPrePage(currentPage); &*+'>UEe5
`DV.+>O-1
returnnew Page(hasPrePage, hasNextPage, q@[QjGj@
everyPage, totalPage, Y;?{|
currentPage, _lamn}(x0
V5UF3'3;}
beginIndex); ["h5!vj
} YB-h.1T-
d3D] k,
privatestaticint getEveryPage(int everyPage){ \ExMk<y_&
return everyPage == 0 ? 10 : everyPage; r"P|dlV-
} KET2Ws[w
7S}_F^
privatestaticint getCurrentPage(int currentPage){ D)L+7N0D~
return currentPage == 0 ? 1 : currentPage; DGS $Ukz&T
} \WxukYH
L7dd(^
privatestaticint getBeginIndex(int everyPage, int o,_?^'@
n*2UnKaJ
currentPage){ JpXlBEio%
return(currentPage - 1) * everyPage; hDF@'G8F
} MF5[lK9e
wB.&}p9p
privatestaticint getTotalPage(int everyPage, int C{U?0!^
k?+?v?I
=
totalRecords){ .yz}ROmN^
int totalPage = 0; E=nIRG|g
vSEuk}pk
if(totalRecords % everyPage == 0) y*qVc E
totalPage = totalRecords / everyPage; As'=tIro
else YNQY4\(
totalPage = totalRecords / everyPage + 1 ; <0Xf9a8>
\W~N
return totalPage; E|iQc8gr&
} F(>Np2oi6
[CQ+p!QZ
privatestaticboolean hasPrePage(int currentPage){ h2G$@8t}I
return currentPage == 1 ? false : true; Q+[n91ey**
}
YtmrRDQs
GPN]9
privatestaticboolean hasNextPage(int currentPage, Fld=5B^}
AE[b},-[
int totalPage){ JRB9rSN^
return currentPage == totalPage || totalPage == LRL,m_gt
}\B><E{G
0 ? false : true; pFOx>u2`a
} k>;`FFQU>
HiZ*+T.B
Q'=x|K#xj
} *\
R ]NV
X%
t1T4
IG2r#N|C#
F3On?x)
Te"ioU?.
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。 $a.JSXyxL
h9}+l
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 Hj^1or3R]
]Sf]J4eQ
做法如下: -t!~%_WCv
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 (A9Fhun
rNXQf'*I
的信息,和一个结果集List: zdB^S%cztS
java代码: ~vm%6CABM
Z^3rLCa
Fs9!S a7v
/*Created on 2005-6-13*/ ?9
<:QE;I>
package com.adt.bo; aTH{'mN
+$ 'Zf0U
import java.util.List;
&u$Q4
'DP1,7
import org.flyware.util.page.Page; 75T%g!c#
(7wc *#}
/** 5_GYrR2
* @author Joa M\uiq38
*/ 3lrT3a3vV
publicclass Result { 11Q1AN
0CnOL!3.I
private Page page; @0Ic3C[rH6
Ni9/}bb
private List content; <? q?Mn
YvaK0p0Z
/** "H'B*vc-
* The default constructor J!dm-L
*/ D+l AhEN
public Result(){ .s?L^Z^
super(); #NEE7'&S
} L>jY.d2w=K
]C!gQq2'a
/** u-QB.iQ+s
* The constructor using fields ha]VWt%}
* f\|w'
* @param page n@<YI
* @param content V'z1
*/ i1 }:8Unxf
public Result(Page page, List content){ G|bT9f$
this.page = page; f z'@_4hg
this.content = content; LBw1g<&
} g];!&R-
Dj"F\j 1
/** NVkV7y X]
* @return Returns the content. `KZm0d{H
*/ 5'OrHk;u
publicList getContent(){ 3#LlDC_WC
return content; %z=le7
} E>6MeO
Vr3Zu{&2
/** KjD/o?JUr
* @return Returns the page. {&&z-^
*/ ?g_3 [Fk
public Page getPage(){ W: z6Koc0
return page; 'TTLo|@"-
} \j$&DCv
G<L;4nA)
/** yuh *
* @param content ik)|{%!K]H
* The content to set. X]ipI$'+C
*/ x+\`gK5
public void setContent(List content){ 2=*H 8'k
this.content = content; OAgniLv
} 9SX +
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/** k
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* @param page y6g&Y.:o
* The page to set. /ixp&Z|7
*/ A7%)~z<
publicvoid setPage(Page page){ NDN7[7E
this.page = page; nGC/R&
} &h}#HS>l
} %Hu5K>ZNYp
VF+KR*
Sj3+l7S?
p?02C#p
2R[:]-b
2. 编写业务逻辑接口,并实现它(UserManager, wo3d#=
eb?x9h
UserManagerImpl) &sl0W-;0
java代码: y\/1/WjBn
))qy;Q,
x`mG<Yt
/*Created on 2005-7-15*/ x'8x
package com.adt.service; p'Y^X
})'B<vq
import net.sf.hibernate.HibernateException; ,V7nzhA2
M`0V~P`^
import org.flyware.util.page.Page; S;Fi?M
{B~QQMEow
import com.adt.bo.Result; d9k0F
OR1
u2tfF
/** EfqX
y>W
* @author Joa [CY9^N
*/ &eJfGt5
publicinterface UserManager { pJ>P[
&j;wCvE4+
public Result listUser(Page page)throws ez7A4>/
R8K&R\
HibernateException; %:i7s-0w
<;lkUU(WT2
} [|v][Hwv
\P[Y`LYL
kBS9tKBWg
]>!K3kB
}H53~@WP>
java代码: Lw1Yvtn
!n`fTK<$
59LG{R2
/*Created on 2005-7-15*/ Usvl}{L[
package com.adt.service.impl; d z|or9&
-uS!\
import java.util.List; &bS,hbD t
<NMEGit
import net.sf.hibernate.HibernateException; b1cy$I
#`^}PuQ
import org.flyware.util.page.Page; )+#` CIv
import org.flyware.util.page.PageUtil; ]U+LJOb
p:&8sO!m
import com.adt.bo.Result; "MeVE#O
import com.adt.dao.UserDAO; ,CJWO bn3
import com.adt.exception.ObjectNotFoundException; "69s)~
import com.adt.service.UserManager; t5Sy V:fP
KS+'|q<?w
/** /WcG{Wdp
* @author Joa !t"4!3
*/ Z{*\S0^ST
publicclass UserManagerImpl implements UserManager { & l<.X
YP oSRA L
private UserDAO userDAO; aj='b.2)
&$+AXzn
/** ,~U>'&M;
* @param userDAO The userDAO to set. x>K Or,f
*/ 1C+13LE$U
publicvoid setUserDAO(UserDAO userDAO){ %UrueMEO
this.userDAO = userDAO; g _9C*
} v&\Q8!r_
w7L{_aom
/* (non-Javadoc) b!t0w{^w
* @see com.adt.service.UserManager#listUser kdiM5l70
f_OQ./`
(org.flyware.util.page.Page) ic:zsuEm
*/ G[ PtkPSJ
public Result listUser(Page page)throws ScOK)nL"
38B2|x
HibernateException, ObjectNotFoundException { 4>
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int totalRecords = userDAO.getUserCount(); &ANf!*<\E
if(totalRecords == 0) b=C*W,Q_#
throw new ObjectNotFoundException As&Sq-NWf
ZvM(Q=^
("userNotExist"); <_L,t 1H{
page = PageUtil.createPage(page, totalRecords); qz_7%c]K[
List users = userDAO.getUserByPage(page); LBeF&sb6
returnnew Result(page, users); 6q\bB
} w{8xpAqm
j^sg6.Z*
} (XTG8W sN
k=$TGqQY?
; nfdGB
bW427B0
Wu/]MBM
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 BKCiIfkZ
5Pc;5
o0C
询,接下来编写UserDAO的代码: au(D66VO
3. UserDAO 和 UserDAOImpl: Qp5VP@t
java代码: ;+R&}[9,A)
:LQYo'@yB
ZDJ`qJ8V
/*Created on 2005-7-15*/ ,Fl)^Gl8?
package com.adt.dao; gx/,)> E.
=ZznFVJ`={
import java.util.List; dES"@?!^
Evq IcZ
import org.flyware.util.page.Page;
J[|y:N
y-b%T|p9
import net.sf.hibernate.HibernateException; 1s&zMWC
)
w5SUb
/** NN{?z!
* @author Joa /U*C\ xMm
*/ s]0{a.Cpv
publicinterface UserDAO extends BaseDAO { !PlEO 2at
Dj?> <@
publicList getUserByName(String name)throws [85spub&}
($MlX BI
HibernateException; @gEUm_#HTs
D/gw .XYL
publicint getUserCount()throws HibernateException; .hb:s,0mP
5V~oIL
publicList getUserByPage(Page page)throws C
82omL
Qy<P463A(l
HibernateException; wU36sCo
~vhE|f
} Q$W
O:R*rJ
,8uqdk-D
^Z+?h&%%
eQm1cgMdz
java代码: (8DC}kckE
-7[@R;FS
7F7{)L
/*Created on 2005-7-15*/ J4C.+![!Ah
package com.adt.dao.impl; W(Fv
l
^)S;xb9
import java.util.List; Rok7n1gW
UgSB>V<?
import org.flyware.util.page.Page; O63<AY@
HRCT}
import net.sf.hibernate.HibernateException; 558V_y:
import net.sf.hibernate.Query; 8'[7
)I=
~W'{p
import com.adt.dao.UserDAO;
x+:UN'"r
d"mkL-
/** =o(5_S.u;
* @author Joa 9&2O9Nz6
*/ 8^2oWC#U(
public class UserDAOImpl extends BaseDAOHibernateImpl lv<*7BCp
0S_~ \t
implements UserDAO { 4[r0G+
uBKgcpvTs
/* (non-Javadoc) 5lmHotj#
* @see com.adt.dao.UserDAO#getUserByName 10~k2{Z
$9#H04.x
(java.lang.String) n
ATuD
*/ J1|\Q:-7p
publicList getUserByName(String name)throws c|y(2K)o[=
/{l$sBUL
HibernateException { ,4e:I.b
String querySentence = "FROM user in class G6P?2@
H5B:;g@
com.adt.po.User WHERE user.name=:name"; qJs<#MQ2
Query query = getSession().createQuery L| +~"'l
286;=rN]*
(querySentence); L#?Ek-
query.setParameter("name", name); h 8S. x)
return query.list(); nwe*BVp
} 85$m[+md
dr}`H,X"3
/* (non-Javadoc) 6r0krbN
* @see com.adt.dao.UserDAO#getUserCount() %D34/=(X
*/ KeB"D!={;
publicint getUserCount()throws HibernateException { WRbj01v
int count = 0; tjGn|+|k
String querySentence = "SELECT count(*) FROM l"T44CL;
]=I@1B;_m
user in class com.adt.po.User"; +F` S>U
Query query = getSession().createQuery #e1>H1eU
z&)A,ryW0
(querySentence); . B9iLI
count = ((Integer)query.iterate().next LVfF[
Ecefi
pG
()).intValue(); &K.d'$q
return count; ]L $\
#
} 3?9IJ5p
YeL#jtC
/* (non-Javadoc) K~{$oD7!
* @see com.adt.dao.UserDAO#getUserByPage o3^l~iT
`/XY>T}-
(org.flyware.util.page.Page) :yr+vcD?
*/ |Q6.29 9
publicList getUserByPage(Page page)throws *8Xh(`
Mj7
~O0 $Suv
HibernateException { y/{fX(aV
String querySentence = "FROM user in class cWaSn7p !X
I\{ 1u
com.adt.po.User"; Y@vTaE^w3
Query query = getSession().createQuery QzVnL U)
a=9:[
(querySentence); 0/MtYIYk
query.setFirstResult(page.getBeginIndex()) ?
7n`A >T
.setMaxResults(page.getEveryPage()); )e+>w=t
return query.list(); ^z IW+:
} R6 .hA_ih
ci.+pF
} $?Hu#Kn,(
4#xDgxg\f
T|e u
9igiZmM
Q800y??&J
至此,一个完整的分页程序完成。前台的只需要调用 u(>^3PJ+
p!7FpxZY
userManager.listUser(page)即可得到一个Page对象和结果集对象 XB^'K2
Vpz\.]
的综合体,而传入的参数page对象则可以由前台传入,如果用 <I\/n<*
Uw. `7b>B
webwork,甚至可以直接在配置文件中指定。 8,4"uuI
{ ]{/t-=
下面给出一个webwork调用示例: /<=u\e'rE
java代码: QL&ZjSN
]Ji.Zk
'Ym9;~(@R
/*Created on 2005-6-17*/ vXf!G`D
package com.adt.action.user; feDlH[$
t7Iv?5]N
import java.util.List; HZC"nb}r4
v6bGjVK[
import org.apache.commons.logging.Log; uK"=i8rs4
import org.apache.commons.logging.LogFactory; ]?kZni8j_
import org.flyware.util.page.Page; 2\MT;;ZTZ
{j?FNOJn
import com.adt.bo.Result; xQ-<WF1i
import com.adt.service.UserService; B$fPgW-
import com.opensymphony.xwork.Action; KE5kOU;
1~Y<//5E
/** qpP=K $
* @author Joa ooj,/IEQ
*/ 3tIVXtUCUk
publicclass ListUser implementsAction{ 9}!qR|l3nR
\^J%sf${
privatestaticfinal Log logger = LogFactory.getLog (&F}/s gbi
XH 4
(ListUser.class); %+W{iu[|
|^"1{7)
private UserService userService; )Xz,j9GzJS
JxdDC^> 0
private Page page; s 8jV(P(O
7hD>As7`/
privateList users; _ @NL;w:!
np"\19^
/* X;
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* (non-Javadoc) a
od-3"7[
* |}s*E_/[
* @see com.opensymphony.xwork.Action#execute() b.JuI
*/ VK\X&Y3l
publicString execute()throwsException{ jKAEm
Result result = userService.listUser(page); DZ'P@f)]
page = result.getPage(); {0Yf]FQb-a
users = result.getContent(); y*jp79G
return SUCCESS; jjB~G^n
} h,u,^ r
PB\(=
/** B[Ku\A6&
* @return Returns the page. )1J R#
*/ n`B:;2X,
public Page getPage(){ {Qf=G|Ah
return page; H7&8\FNa
} FF`T\&u
by1<[$8r
/** ;s = l52
* @return Returns the users. i4Q@K,$
*/ j?3wvw6T
publicList getUsers(){ ` xEx^P^7
return users; $kdB |4C
} g#pr yYz
O-0x8 O^B
/** ?DS@e@lx
* @param page fM :]&
* The page to set. T?CdZc.
*/ MO]F1E?X
publicvoid setPage(Page page){ }#RakV4
this.page = page; ,GhS[VJjR
}
,h m\
X6w6%fzOH>
/** `iFmrC<
* @param users <y('hI'
* The users to set. Wq D4YGN
*/ \g`\`e53?
publicvoid setUsers(List users){ d=$Mim
this.users = users; Z!a=dnwHz
} `!3SF|x&
Zgp4`)}:
/** Tt`u:ZwhF
* @param userService #'nr
Er <
* The userService to set. ;LKkbT
5
*/ L^/5ux
publicvoid setUserService(UserService userService){ e9Wa<i8
this.userService = userService; hE'-is@7
} [:
n'k
} +5g_KS
&T?RZ2
oz\!V*CtK
K-^\"
W8
q5J5>
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, Gt8M&S-;
,a{P4Bq
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 RtkEGxw*^
Y#ap*
么只需要: _P#|IAq*
java代码: bI7Vwyz
Ke;E1S-~
"b~+;<}Q
<?xml version="1.0"?> r Xt}6[S
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork g>E LGG|Q
TM__I\+Q
1.0//EN" "http://www.opensymphony.com/xwork/xwork- 60^`JVGWH
p;`>e>$
1.0.dtd"> j1Y~_
L Tm2G4+]
<xwork> U#7#aeI
y1jCg%'H
<package name="user" extends="webwork- yM6pd U]i
n K1Slg#U
interceptors"> >mbHy<<
a Yg6H2Un
<!-- The default interceptor stack name =g7x'
kN
;Zcswt8]u
--> gs^Xf;gvI
<default-interceptor-ref *?@?f&E/
]\-A;}\e
name="myDefaultWebStack"/> ch*8B(:
(U DnsF
<action name="listUser" o*+"|
OR P\b
class="com.adt.action.user.ListUser"> X~bX5b[P
<param CImWd.W9~
`P@< 3]
name="page.everyPage">10</param> Y,qI@n<
<result hk;5w{t}}
h]5(].
name="success">/user/user_list.jsp</result> Q^P}\wb>
</action> nUaJzPl
'&P%C" 5
</package> Y1w9y
v4!VrI
</xwork> %"i(K@
d(ZO6Nr Q
^`i#$
^x ]r`b
(q/e1L-S
dohA0
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 #H&|*lr
: g7@PJND
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。 B6+khuG(
+zqn<<9
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 7uqzm
A;q9rD,_
SBu"3ym
$j%'{)gK
L]|gZ&^
我写的一个用于分页的类,用了泛型了,hoho n1ZbRV
(!u~CZ;
java代码: ^cC,.Fdw
{S]}.7`l9(
OU\ ~::
package com.intokr.util; zEX
L tO!umM
import java.util.List; +yG~T
tn\yI!a
/** /obfw^
* 用于分页的类<br> a@K%06A;'
* 可以用于传递查询的结果也可以用于传送查询的参数<br> JJ-( Sl
* Uk wP
* @version 0.01 *}qWj_RT
* @author cheng sP pH*,(
*/ -a}Dp~j
public class Paginator<E> { 5+0gR
&|j
privateint count = 0; // 总记录数 Lz}OwKl
privateint p = 1; // 页编号 0@0w+&*"@
privateint num = 20; // 每页的记录数 4&lv6`G `
privateList<E> results = null; // 结果 D(op)]8
GRIti9GD
/** [T4J{y64Y
* 结果总数 )2KF}{
*/ S&5&];Ag
publicint getCount(){ FBX'.\@`
return count; Wx%H%FeK
} kOrZv,qFG[
_#E0g'3
publicvoid setCount(int count){ {GT*ZU*
this.count = count; lWk>z; d
} i$"F{|Z0
U BU=9a5
/** tyDU
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* 本结果所在的页码,从1开始 h|9L5
* RZ?jJm$
* @return Returns the pageNo. \[i1JG
*/ `,*3[
publicint getP(){ [ZwjOi:)
return p; lN
4oW3QT
} e`_LEv
;W
)Y
OT
/** ij`w} V
* if(p<=0) p=1 ea2ayT
* 9Q^r
O26+
* @param p
K=Z|/Kkh
*/ )gUR@V>e2
publicvoid setP(int p){ A1$TXr
if(p <= 0) ?#G$=4;i
p = 1; uk:(pZ-uJ
this.p = p; 'W^YM@
} cxC6n%!;y
,.8KN<A2]'
/** vzAax k%
* 每页记录数量 epe)a
*/ CI0C1/:@
publicint getNum(){ |kg7LP3(8,
return num; |$Sedzj'
} N7zft
? pmHFlx
/** VQt0 4?
* if(num<1) num=1 3,3N^nSD
*/ e2TiBTbQaF
publicvoid setNum(int num){ 9d659iC
if(num < 1) ^98~U\ar
num = 1; !sP{gi#=
this.num = num; wH&!W~M
} f|c{5$N!
`wEb<H
/** 20 h, ^
* 获得总页数 '3fu
*/ s?}e^/"v
publicint getPageNum(){ RWZSQ~
return(count - 1) / num + 1; ;7V%#-
} L|7R9+ZG
]y'>=a|T
/** ^A/k)x6
* 获得本页的开始编号,为 (p-1)*num+1 g3/W=~r
*/ #&aqKVY
publicint getStart(){ 3z?> j]
return(p - 1) * num + 1; B%b4v
} UKvW Jnz
xGg )Y#
/** - % h.t+=U
* @return Returns the results. :U%W%
*/ nh>vixe
publicList<E> getResults(){ CYP q#rd
return results; .@U@xRu7|
} ^"2J]&x`G
Om\vMd@!
public void setResults(List<E> results){ 5L%'@`mX
this.results = results; LckK\`mh
} Hg izW
zu{P#~21
public String toString(){ ,!y$qVg'\f
StringBuilder buff = new StringBuilder G 4X|Bka
b=NxUd O
(); xsbE TP?
buff.append("{"); WPMSm<[
buff.append("count:").append(count); )9`qG:b'
buff.append(",p:").append(p); l<LI7Z]A
buff.append(",nump:").append(num); AJ`h9%B
buff.append(",results:").append BM
.~ 5\
'Aq{UGN
(results); 06Sceq
buff.append("}"); .j0$J\:i
return buff.toString(); aP+X}r
} Be2DN5)
[D4SW#
} "$^ ~!1~
WlC:l
k"iOB-@B+