Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 xDU{I0M
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 QQnpy.`:/
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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 ]f3eiHg*
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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 'F)93SwU
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分页支持类: xejQ!MAB
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java代码: R0l5"l*@+
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package com.javaeye.common.util; N}j]S{j}'
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import java.util.List; 8$+mST'4N
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publicclass PaginationSupport { mO6rj=L^
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publicfinalstaticint PAGESIZE = 30; ~`uEZ
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privateint pageSize = PAGESIZE; [%);N\o2Y
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privateList items; Q=,6W:j
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privateint totalCount; j;GH|22
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privateint[] indexes = newint[0]; /f5*KRM
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privateint startIndex = 0; t==CdCl
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public PaginationSupport(List items, int O7M8!3Eqm
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totalCount){ #GJ{@C3H8Q
setPageSize(PAGESIZE); z^ai *
setTotalCount(totalCount); b6mSPH@
setItems(items); d3m!34ml
setStartIndex(0); = 02$Dwr
} OzVCqq"]
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public PaginationSupport(List items, int )}/ ycTs
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totalCount, int startIndex){ B#|c$s{
setPageSize(PAGESIZE); F1Jd-3ei
setTotalCount(totalCount); fAMk<?
setItems(items); #{m~=1%;Ya
setStartIndex(startIndex); 8l?mNapy
} _+OnH!G0
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public PaginationSupport(List items, int zeHf(N
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totalCount, int pageSize, int startIndex){ Yq$KYB j
setPageSize(pageSize); <r@w`G
setTotalCount(totalCount); xF#'+Y
setItems(items); H n^)Xw
setStartIndex(startIndex); !T'`L{Sj
} ag_RKlM3
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publicList getItems(){ ;*H@E(g
return items; D?Mj<||
} hR g?H
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publicvoid setItems(List items){ ,w9:)B7
this.items = items; 'P:u/Sq?m
} i7%v2_
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publicint getPageSize(){ yDE0qUO
return pageSize; |#>:@{X<
} @L 9C_a
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publicvoid setPageSize(int pageSize){ xy^t_];X
this.pageSize = pageSize; <-]qU}-
} JNJ96wnX1
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publicint getTotalCount(){ b%-S'@ew
return totalCount; y[C++Q
} 4 kNiS^h
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publicvoid setTotalCount(int totalCount){ E.'v,GYe
if(totalCount > 0){ At0ahy+
this.totalCount = totalCount; _s1pif
int count = totalCount / Jp d|<\Ml
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pageSize; -lb,0
if(totalCount % pageSize > 0) 5}+&Em":
count++; YLx4qE
indexes = newint[count]; lWR".
for(int i = 0; i < count; i++){ |+aUy^
indexes = pageSize * RCL}bE
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i; C'wRF90
} MzRliH8e
}else{ `hVi!Q]*P
this.totalCount = 0; @{X<|,W9w
} J[k,S(Y
} G0izZWc
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publicint[] getIndexes(){ nB &[R
return indexes; z>6hK:27
}
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publicvoid setIndexes(int[] indexes){ NKSK+ll2
this.indexes = indexes; ;UAi>//#
} gfW_S&&q
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publicint getStartIndex(){ YcmLc)a7
return startIndex; ~~B`\!n7
} t++
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publicvoid setStartIndex(int startIndex){ l!d |luqbA
if(totalCount <= 0) &>xd6-
this.startIndex = 0; (v)/h>vS
elseif(startIndex >= totalCount) DD?zbN0X
this.startIndex = indexes m-v0=+~&
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[indexes.length - 1]; 4pJ #fkc^
elseif(startIndex < 0) +NT8dd
this.startIndex = 0; O6[4=4L
else{ _1hiNh$
this.startIndex = indexes L%CBz]`
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[startIndex / pageSize]; :f/T$fa*
} JG:li} N
} 0^-1/Ec
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publicint getNextIndex(){ o?O> pK
int nextIndex = getStartIndex() + #3_t}<fX
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pageSize; XzD+#+By
if(nextIndex >= totalCount) [gybdI5wur
return getStartIndex(); ( Ev=kO
else '|
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return nextIndex; TpH-_ft
} L|*0
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publicint getPreviousIndex(){ F*['1eAmdY
int previousIndex = getStartIndex() - 11g_!X -g@
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pageSize; v.q`1D1=t
if(previousIndex < 0) 0zHMtC1,
return0; |lG7/\A
else G &QG Q
return previousIndex; /7CV7=^d,
} EW~M,+?
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} ?nCo?A
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抽象业务类 nc[Kh8N9
java代码: xo.k:F
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/** !SPu9:
* Created on 2005-7-12 B'D\l\w
*/ Gv+$7{
package com.javaeye.common.business; `bJ?8~ 8*
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import java.io.Serializable; U^&,xz$Cg
import java.util.List; k5@PZFV
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import org.hibernate.Criteria; |\<L7|hb9
import org.hibernate.HibernateException; Errs6
import org.hibernate.Session; crbph.0
import org.hibernate.criterion.DetachedCriteria; ]/6i#fTw
import org.hibernate.criterion.Projections; X? l5}
import v 1VH&~e
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org.springframework.orm.hibernate3.HibernateCallback; 1$#1
import AeR*79x
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org.springframework.orm.hibernate3.support.HibernateDaoS 53<.Knw5a
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upport; &~KAZ}xu
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import com.javaeye.common.util.PaginationSupport; w\zNn4B})A
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public abstract class AbstractManager extends _PPn
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HibernateDaoSupport { UGD B4S
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privateboolean cacheQueries = false; ;@FCaj&
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privateString queryCacheRegion; vs%d}]v
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publicvoid setCacheQueries(boolean {X EX0|TZ
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cacheQueries){ \&MJ(F>vJ
this.cacheQueries = cacheQueries; {%+UQ!]d8
} 3]li3B'
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publicvoid setQueryCacheRegion(String cw/E?0MWb
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queryCacheRegion){ Ly q[gQjr
this.queryCacheRegion = vI20G89E
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queryCacheRegion; V.-cm51I
} :Xs3Vh,V
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publicvoid save(finalObject entity){ mfx-Ja_a
getHibernateTemplate().save(entity); 5q;c=oRUj
} z)ndj
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publicvoid persist(finalObject entity){ jR2^n`D
getHibernateTemplate().save(entity); W+I""I*mV
} Y3JIDT^
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publicvoid update(finalObject entity){ p5aqlYb6r
getHibernateTemplate().update(entity); nIWY<Z"
} Vtv~jJ{m
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publicvoid delete(finalObject entity){ D!V~g72j
getHibernateTemplate().delete(entity); `4-N@h
} <8ih >s(C
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publicObject load(finalClass entity, kD
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finalSerializable id){ fb[? sc
return getHibernateTemplate().load Q%:Z&lgy
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(entity, id); 9I [k3
} NXMZTZpB7
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publicObject get(finalClass entity, zSagsH |W
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finalSerializable id){ %)w7t[A2D
return getHibernateTemplate().get AAF']z<4_"
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(entity, id); ](^FGz
} &S39SV
}ag;yf;
publicList findAll(finalClass entity){ Gc_KS'K@$
return getHibernateTemplate().find("from AO,^v+$
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" + entity.getName()); i1 c[Gk.o
} wpD}#LRfm
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publicList findByNamedQuery(finalString *z^Au7,&
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namedQuery){ SmUiH9qNd,
return getHibernateTemplate i3cMRcS;
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().findByNamedQuery(namedQuery); pf&U$oR4
} \c1>15
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publicList findByNamedQuery(finalString query, 9
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finalObject parameter){ @<yY Mo7
return getHibernateTemplate 40O@a:q*
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().findByNamedQuery(query, parameter); 32Wa{LG;2
} `{NbMc\
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publicList findByNamedQuery(finalString query, iD<}r?Z
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finalObject[] parameters){ p}e| E!
return getHibernateTemplate 1'H!S%fS
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().findByNamedQuery(query, parameters); qIxe)+.
} .O SQ8W}
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publicList find(finalString query){ 5cb8=W-
return getHibernateTemplate().find b3ys"Vyn
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(query); ,/"0tP&_;
} p!EG:B4
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publicList find(finalString query, finalObject |Yv,zEY)
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parameter){ V`rxjv}!
return getHibernateTemplate().find e?N3&ezp
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(query, parameter); ==S^IBG
} OVE?;x>n/1
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public PaginationSupport findPageByCriteria hcz!f
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(final DetachedCriteria detachedCriteria){ S263h(H
return findPageByCriteria Gr'|nR8
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); U?ZWDr"*`w
} kG5Uc83#G
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public PaginationSupport findPageByCriteria CSH*^nk':O
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(final DetachedCriteria detachedCriteria, finalint @ +a}O
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startIndex){ &x$ps
return findPageByCriteria ZH`(n5
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(detachedCriteria, PaginationSupport.PAGESIZE, 4wWfaL5"
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startIndex); 4>/i,_&K K
} )$K\:w>
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public PaginationSupport findPageByCriteria R,fAl"wMu
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(final DetachedCriteria detachedCriteria, finalint cYBjsN(!A|
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pageSize, !r9rTS]
finalint startIndex){ ?X Rl\V
return(PaginationSupport) !}sF#
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getHibernateTemplate().execute(new HibernateCallback(){ ce*?crOV
publicObject doInHibernate Kw2]J)TO
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(Session session)throws HibernateException { Wz#ZkNO
Criteria criteria = g`~;"%u7cn
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detachedCriteria.getExecutableCriteria(session); bP,Ka
int totalCount = >qUD_U3A
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((Integer) criteria.setProjection(Projections.rowCount CAmIwAx6;
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()).uniqueResult()).intValue(); k5*Z@a
criteria.setProjection x3F94+<n{
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(null); _#uRKy<`N
List items = jUDE)~h
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criteria.setFirstResult(startIndex).setMaxResults uJ8FzS>[V
1^ iLs
(pageSize).list(); =dmxE*C
PaginationSupport ps = O-box?
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new PaginationSupport(items, totalCount, pageSize, DiZ;FHnaG?
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startIndex); J%
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return ps; F5OQM?J
} N34bB>_
}, true); d[*NDMO
} Sy<io@df
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public List findAllByCriteria(final uo*lW2&U
?j)#\s2
DetachedCriteria detachedCriteria){ ?A~=.u@[d
return(List) getHibernateTemplate Kzy9i/bL
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().execute(new HibernateCallback(){ R]RLy#j
publicObject doInHibernate l@]Fzl
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(Session session)throws HibernateException { b@sq}8YD|z
Criteria criteria = \Ym!5,^o
.4[M-@4+]
detachedCriteria.getExecutableCriteria(session); ylDfr){
return criteria.list(); = )4bf"~8
} 8#9OSupp
}, true); "{3MXAFe
} ;Wsl 'e/
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public int getCountByCriteria(final ]mjKF\
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DetachedCriteria detachedCriteria){ e@&2q{Gi=
Integer count = (Integer) Z-M4J;J@}
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getHibernateTemplate().execute(new HibernateCallback(){ lTFo#p_(
publicObject doInHibernate "{d[V(lE"
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(Session session)throws HibernateException { \jS^+Xf?^
Criteria criteria = f#hmMa
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detachedCriteria.getExecutableCriteria(session); W)Y:2P<.
return '#~Sb8
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criteria.setProjection(Projections.rowCount )}vUYTU1
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()).uniqueResult(); Mko,((>I1
} |uX&T`7?-
}, true); }.=@^-JBA5
return count.intValue(); AJ6O>Euq
} l1%*LyD
} ZmI#-[/
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用户在web层构造查询条件detachedCriteria,和可选的 4 XGEw9`3
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 fSGaUBiq}
a)6?:nY$
PaginationSupport的实例ps。 gEq6[G
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ps.getItems()得到已分页好的结果集 e`)zR'As
ps.getIndexes()得到分页索引的数组 O<XNI(@
ps.getTotalCount()得到总结果数 @v.?z2h
ps.getStartIndex()当前分页索引 Bu{%mm(
ps.getNextIndex()下一页索引 RhE|0N=
ps.getPreviousIndex()上一页索引 u
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 q\~D:z$+CO
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,尤其是上面的示例代码,让我着实觉得该对我原来的分页查询做 SV^[)p)
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一下代码重构了。 Ac/LNqIs
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我把原本我的做法也提供出来供大家讨论吧: 5o0H7k]
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首先,为了实现分页查询,我封装了一个Page类: |voZ0U
java代码: lO}I>yo}\
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/*Created on 2005-4-14*/ ,{Z!T5 |
package org.flyware.util.page; 3v)``
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/** Su'l &]
* @author Joa T\Jm=+]c!
* @^HZTuP2;
*/ Tb]
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publicclass Page { \x"BgLSE
<V#]3$(S
/** imply if the page has previous page */ #O7phjzgD
privateboolean hasPrePage; @j%7tfW
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/** imply if the page has next page */
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privateboolean hasNextPage; 1#2L9Bi
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/** the number of every page */ ZPHatC
privateint everyPage; xJFxrG'c
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/** the total page number */ "h&[6-0'
privateint totalPage; X\BdN Hr
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/** the number of current page */ zZ8:>2Ps(
privateint currentPage; X
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/** the begin index of the records by the current FXid=&T@0D
mEV@~){
query */ >}86#^F
privateint beginIndex; j 2e|
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/** The default constructor */ )N&95\u
public Page(){ ; VQ:\fG
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} ) =|8%IrB
` )~CT
/** construct the page by everyPage N2C f(
* @param everyPage !Eb!y`jK
* */ ul\FZT 4
public Page(int everyPage){ $u,`bX
this.everyPage = everyPage; F4g3l
} ~JOC8dO
8`q"] BQN
/** The whole constructor */ '^.3}N{Fo
public Page(boolean hasPrePage, boolean hasNextPage, oCB#i~|>a
w5a;ts_x
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int everyPage, int totalPage, h9 +76
int currentPage, int beginIndex){ <{.pYrn
this.hasPrePage = hasPrePage; :) T#.(mR
this.hasNextPage = hasNextPage; wgZ6|)!0
this.everyPage = everyPage; /tq e:*
this.totalPage = totalPage; $XrX(l5
this.currentPage = currentPage; Y,X0x-
this.beginIndex = beginIndex; \~""<*Hz
} 8b+%:eJ
cUU"*bA#
/** 7i9wfc h$U
* @return \}7xgQ>oV
* Returns the beginIndex. >+*lG>!z
*/ GUsJF;;V
publicint getBeginIndex(){ IVG77+O# }
return beginIndex; 7*47mJyc
} }kk[lvhJ
N!13QI
H
/** p[D,.0SuC
* @param beginIndex l/bZE.GJ
* The beginIndex to set. }M9I]\
*/ +kOXa^K
publicvoid setBeginIndex(int beginIndex){ )'`@rq!
this.beginIndex = beginIndex; FX/f0C3CK
} #vT~D>zj
R"e53 3
/** ;x4yidb6
* @return \B8[UZA.&
* Returns the currentPage. 2!}rHw
*/ .IORvP-M&
publicint getCurrentPage(){ f_> lz
return currentPage; c)17[9"
} R9%"Kxm
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/** e:= +~F(f
* @param currentPage g<MCvC@
* The currentPage to set. aX35^K /
*/ 'k9 1;T[
publicvoid setCurrentPage(int currentPage){ o>\epQt~/p
this.currentPage = currentPage; rd}|^&e!Dy
} ,}$[;$ye
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/** FJ O-p
* @return Iz I
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* Returns the everyPage. lkgB,cflpi
*/ Yfx'7gj
publicint getEveryPage(){ ~
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return everyPage; ]Hrw$\Ky
} ?uqPye1fc
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/** /QVhT
* @param everyPage :-1
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* The everyPage to set. mbO.Kyfen
*/ RMBPm*H
publicvoid setEveryPage(int everyPage){ K=;oZYNd
this.everyPage = everyPage; 9AZpvQ
} oF(|NS^
UN`O*(k[
/** rs:a^W5t
* @return =7<g;u
* Returns the hasNextPage. AJ85[~(lX
*/ LW+^m6O
publicboolean getHasNextPage(){ hN.{H:skL)
return hasNextPage; hxsW9
} <qCfw>%2F
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/** %x|0<@b7-
* @param hasNextPage UoKXo*W2
* The hasNextPage to set. Wj31mV
*/ _9"%;:t
publicvoid setHasNextPage(boolean hasNextPage){
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this.hasNextPage = hasNextPage; of?'FrU
} ?h'd\.j{
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/** ?-9It|R
* @return 0o-KjX?kP
* Returns the hasPrePage. qX!P:M
*/ p ^Dm w0y
publicboolean getHasPrePage(){ |1^
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return hasPrePage; kY`L[1G$
} K1^x+I7%U[
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/** y4N=v{EbL
* @param hasPrePage ;TG<$4N
* The hasPrePage to set. yX|0R
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*/ / FA0(< -}
publicvoid setHasPrePage(boolean hasPrePage){ G,h=5y9_J
this.hasPrePage = hasPrePage; ^`oyf{w@
} .wz.Jr`{
S(h+,+289
/** 0?8{q{ o+
* @return Returns the totalPage. >TZyax<:
* = $awUy
*/ g:CMIe4
publicint getTotalPage(){ RS[>7-9
return totalPage; khtYn.eaL
} \t\ZyPxn
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/** DZ~qk+,I
* @param totalPage Id;YIycXe
* The totalPage to set. e|jmOYWG
*/ V?"SrXN>
publicvoid setTotalPage(int totalPage){ ZF6?N?t}h8
this.totalPage = totalPage; HCTjFW>C
} o&b1-=MC2
3,RaM^5dV
} Erd)P
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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 ^&6'FE
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6
个PageUtil,负责对Page对象进行构造: UN6Du\)]d
java代码: c>nXnN
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/*Created on 2005-4-14*/ }tRY,f
package org.flyware.util.page; S.X*)CBB
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import org.apache.commons.logging.Log; bI?YNt,
import org.apache.commons.logging.LogFactory; 4tv}V:EO
vPA {)l\K
/** c3$h-M(jVJ
* @author Joa =UW!
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* t^zmvPDK
*/ ">^O{X\
publicclass PageUtil { w0iv\yIRQ
B1!b@0^
privatestaticfinal Log logger = LogFactory.getLog 0kdPr:B Q0
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(PageUtil.class); o<r|YRzQl
kxp, ZP
/** 1^4z/<ZWm
* Use the origin page to create a new page nR1QS_@{L
* @param page Dtw1q-
* @param totalRecords 0+P<1ui
* @return >u:t2DxE
*/ %8a886;2
publicstatic Page createPage(Page page, int #}Qzu~
mOkf
totalRecords){ DlWnz-
return createPage(page.getEveryPage(), P:gN"f6
;P#c!
page.getCurrentPage(), totalRecords); xbv
} 5_MqpCL
M{ mdh\
/** QXcSDJ
* the basic page utils not including exception Gcseq
udV.$N
handler c{dge/2yb
* @param everyPage 8(EK17rE`
* @param currentPage 6.!Cm$l
* @param totalRecords cnR.J
* @return page B8'e,9
*/ "5,tEP!
publicstatic Page createPage(int everyPage, int `Y~EL?
<[eE5X(
currentPage, int totalRecords){ oS/cS)N20
everyPage = getEveryPage(everyPage); N=QeeAI}}m
currentPage = getCurrentPage(currentPage); @rO4BTi>O
int beginIndex = getBeginIndex(everyPage, y(!YN7_A
P~5[.6gW
currentPage); Uczb"k5
int totalPage = getTotalPage(everyPage, @1w9!\7Vt
e)WpqaI
totalRecords); 5 B lptC
boolean hasNextPage = hasNextPage(currentPage, o`8dqP
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totalPage); e /4{pe+,
boolean hasPrePage = hasPrePage(currentPage); 9{;cp?\)M
+v`?j+6z
returnnew Page(hasPrePage, hasNextPage, F( w
everyPage, totalPage, Wx<fD()
currentPage, ^" EsBt
2$MIA?A"Y
beginIndex); f;u<r? >Z
} pS3TD"p
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privatestaticint getEveryPage(int everyPage){ l#W9J.q(
return everyPage == 0 ? 10 : everyPage; q-g3!
} $H9+>Z0(
b`=\<u8
privatestaticint getCurrentPage(int currentPage){ %ifq4'?Z
return currentPage == 0 ? 1 : currentPage; '<A:`V9M}v
} d&dp#)._8
TfYXF`d
privatestaticint getBeginIndex(int everyPage, int {q[l4_
`Eijy3>h
currentPage){ Tw!]N%E
return(currentPage - 1) * everyPage; >0W:snNK
} o<hT/ P
u7oHqo`
privatestaticint getTotalPage(int everyPage, int dsx'l0q 'i
G8y:f%I!b
totalRecords){ YR2Q6}xR
int totalPage = 0; J 5Nz<
S+d@RMdes
if(totalRecords % everyPage == 0) 0jlwL
totalPage = totalRecords / everyPage; hpxqL%r
else E0miX)AG
totalPage = totalRecords / everyPage + 1 ; -gWqq7O
| Vtd!9
return totalPage; m@r+M"!R
} ]pZxbs&Vb
\M
H\!
privatestaticboolean hasPrePage(int currentPage){ RGw=!0V
return currentPage == 1 ? false : true; {c'2{`px 5
} CMm:Vea
kIb)I(n
privatestaticboolean hasNextPage(int currentPage, 8Rgvb3u
iBq|]
int totalPage){ PhHBmMGL
return currentPage == totalPage || totalPage == Ye '=F
u*I=.
0 ? false : true; CLb~6LD
} { *"I4
{xw"t9(fE
Rn(vG-xQ
} `h>a2
Q -!,yCu
u}eqU%
y5d=r]_S:
E|(T(4;
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 s&<6{AU(id
3HU_~%l
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 \
2$nFr?0
+bG^SH2ke
做法如下: s~@4
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 ~w&P]L\dB
7IrbwAGZ3
的信息,和一个结果集List: }=1#ANM1
java代码: a@ E+/9
qno8qF*
1}moT#
/*Created on 2005-6-13*/ ?R7>xrp5
package com.adt.bo; xQ[~ c1
ZfPWH'P
import java.util.List; ionFPc].
Sn I-dXNF
import org.flyware.util.page.Page; i@=0fHiZQ
?onaJ=mT
/** 8X6F6RK6,1
* @author Joa CCCd=s.
*/ W6_~.m"b
publicclass Result { Xknp*(9
<5R`E(
private Page page; rOt`5_2f
C%$:Oq
private List content; VJK?"mX
:^c' P<HM
/** #J1vN]g
* The default constructor wABaNB=9;
*/ hL1q9%
public Result(){ *hhPCYOm
super(); LL|uMe"Jb
} DrfOz#a0Uu
HLL[r0P`F
/** 'W!N1W@
* The constructor using fields 8oM]gW;J~
* ?-40bb
* @param page |\yVnk!c
* @param content V Ae@P
*/ q
.[hwm
public Result(Page page, List content){ %^e~;i=2
this.page = page; [0M2`x4`
this.content = content; 4fK(<2i
} > 3<P^-9L
,/d
R
/** ' }G!D
* @return Returns the content. W'3&\}
*/ [I4:R_\
publicList getContent(){ [(Z sQK
return content; av-l_iE
} <M(Jqb cWa
bPaE;?m
/** +(v<_#wR-
* @return Returns the page. qH3<,s*
*/ G+k[.
public Page getPage(){ mN5`Fct*A>
return page; WD wW`
} <78]OZ] Z
X67.%>#3
/** ]}4{|& e
* @param content _R&}CP
* The content to set. !ke_?+8sY
*/ l>l)m-;O
public void setContent(List content){ aNZJs<3;'D
this.content = content; 3kAmRU
} ?^F*M#%?
m!{}Y]FZn
/** I)wjTTM5
* @param page 5|&:l8=
* The page to set. s0,\[rM
*/ Oeua<,]Z~
publicvoid setPage(Page page){ 4WK@ap-~
this.page = page; BUH~aV
} KmuE#Ia
} q1 :Y]Rbe
G~,K$z/-l
(~YFm"S
=5NM
=K
R|7yhsJq,
2. 编写业务逻辑接口,并实现它(UserManager, rg Q6/3}qc
JNQiCK,)}M
UserManagerImpl) qT`sPEs;V
java代码: z^+`S:
\(y6o}aW
#+mt}w/
/*Created on 2005-7-15*/ w28!Yj1Q
package com.adt.service; MQL1 />j;
,2Y PD4
import net.sf.hibernate.HibernateException; fz%I'+!
f tVA
import org.flyware.util.page.Page; %bM^/7
rlj @'
import com.adt.bo.Result; ;]ojfR=?%
]B;GU
/** r 5!ie!5gE
* @author Joa
Vf:w.G A
*/ \Y)pm9!
publicinterface UserManager { oY!nM%z/
44H#8kV
public Result listUser(Page page)throws 13oR-Stj|
nC^|83
HibernateException; V^O
dTM
[emUyF
} j, SOL9yg
(kpn"]^'
=bJj;bc'5
g~ tG
zCrDbGvqF`
java代码: f
wN
ahagt9[,:F
(!h%)
_?.l
/*Created on 2005-7-15*/ sOc<'):TK
package com.adt.service.impl; l3Vw?f
8 *@knkJ
import java.util.List; s1,kTde
@\[UZVmBw
import net.sf.hibernate.HibernateException; "%O,*t
jM%qv
import org.flyware.util.page.Page; 1:-^*
import org.flyware.util.page.PageUtil; __U;fH{c
F$kLft[:
import com.adt.bo.Result; TGnyN'P|
import com.adt.dao.UserDAO; s>Eu[uA
import com.adt.exception.ObjectNotFoundException; M8Y\1#~
import com.adt.service.UserManager; m5HP56a
EjsAV F
[@
/** jEQr{X7bEL
* @author Joa x`'2oz=,F4
*/ pWo`iM& F
publicclass UserManagerImpl implements UserManager { 5t6!K?}
b .9]b
private UserDAO userDAO; '}a[9v76
m?;aTSa
/** po~l8p>
* @param userDAO The userDAO to set. +MG(YP/l
*/ 7
4rmxjiN
publicvoid setUserDAO(UserDAO userDAO){ h1 \)_jxA
this.userDAO = userDAO; 3}::"X
} w H&Rjn
L@*0wx`fU
/* (non-Javadoc) b* 4[)Yg4
* @see com.adt.service.UserManager#listUser
&I8,<(`
,|?-\?I
(org.flyware.util.page.Page) 5.J$0wK'6
*/ }8E//$J
public Result listUser(Page page)throws ?}*A/-Hx0U
'T54k
HibernateException, ObjectNotFoundException { Y21,!$4gb
int totalRecords = userDAO.getUserCount(); sY?pp
'}a
if(totalRecords == 0) owA3>E5t&
throw new ObjectNotFoundException ZoJ:4uo
N`
fo])=KM
("userNotExist"); 'U<-w$!f+^
page = PageUtil.createPage(page, totalRecords); {;4AdZk
List users = userDAO.getUserByPage(page); ^FSUK
returnnew Result(page, users); ]JQk,<l5E
} Zf<M14iM
~__]E53F
} y6KI.LWR9
"rz|sbj
9 F~U%
>GX
EZkg0FhkZ
q|J3]F !n
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 \XR%pC
4kO[|~#
询,接下来编写UserDAO的代码: oD,f5Ci-
3. UserDAO 和 UserDAOImpl: A3%s5`vNvH
java代码: >'#G$f
$rf4h]&<
dbGW`_zQ4
/*Created on 2005-7-15*/ }?B=R#5
package com.adt.dao; \nV|Y=5
t5h]]TOz
import java.util.List; [ 'pk/h
X<s']C9c
import org.flyware.util.page.Page; 2-821Sf#h
\(_FGa4j
import net.sf.hibernate.HibernateException; <Vp7G%"'W
jqHg'Fq
/** X#mm
Z;P
* @author Joa Z(AI]wk3<
*/ 11}fPWK
publicinterface UserDAO extends BaseDAO { .?b2Bd!MC
.fxI)
publicList getUserByName(String name)throws CQfrAk4mu
&F"Mkyf
HibernateException; <Gzy*1Q&
UJkg|eu
publicint getUserCount()throws HibernateException; #3maT*JY
'UO,DFq[Fl
publicList getUserByPage(Page page)throws ywlN4=
7G}vQO
HibernateException; 0N.tPF}
Xr~6_N{J
} hd1H
yvo~'k#c
'01H8er
|i-Q fpn
xKKL4ws
java代码: D3yG@lIP3
{O*<1v9<
*&B1(&{:V
/*Created on 2005-7-15*/ tYyva
package com.adt.dao.impl; 2X2,(D!
GP ;c$pC
import java.util.List; \sFdp!M}2
N1WP
import org.flyware.util.page.Page; j.4oYxK!s/
cA ;'~[
import net.sf.hibernate.HibernateException; W?{:HV
import net.sf.hibernate.Query; }AG$E}~/
ZjY_AbD
import com.adt.dao.UserDAO; w[PWJ! <
HbF.doXK
/** MrjET!`.jC
* @author Joa 9z5K -s
*/ $DW3H1iW
public class UserDAOImpl extends BaseDAOHibernateImpl eSXt"t
/_E:sI9(
implements UserDAO { $enh>!mU
u4B, |_MK
/* (non-Javadoc) *!UY;InanX
* @see com.adt.dao.UserDAO#getUserByName 5=Mm=HyI2
|jm|/{lc
(java.lang.String) 3ydOBeY
*/ w\=zTHo88
publicList getUserByName(String name)throws ;nG"y:qq
]@1YgV
HibernateException { XhFa9RC
String querySentence = "FROM user in class ke|v|@
94%gg0azp
com.adt.po.User WHERE user.name=:name"; j~V@0z.
Query query = getSession().createQuery Ea1{9>S
"+s#!Fh *
(querySentence); *w4jE T>
query.setParameter("name", name); ,.tT9?
m
return query.list(); EDvK9J
} &$ F0
ayyn6a8
/* (non-Javadoc) A|tee@H*0
* @see com.adt.dao.UserDAO#getUserCount() Mw7!w-1+
*/ +Tc4+q!
publicint getUserCount()throws HibernateException { "5e~19
int count = 0; >]Hz-2b
String querySentence = "SELECT count(*) FROM @~fg[)7M
MK[l*=\s
user in class com.adt.po.User"; /ee:GjUkB
Query query = getSession().createQuery Ken |!rL
bv0B
(querySentence); -@i)2J_WP
count = ((Integer)query.iterate().next 6BVV2j)zl:
0.O pgv2K
()).intValue(); JY0t Hs
return count; Y+<C[Fiq
} (w]w
2&YD
`|wH=
/* (non-Javadoc) 0IBVR,q
* @see com.adt.dao.UserDAO#getUserByPage :gY$/1SYD
/7*jH2
(org.flyware.util.page.Page) lO8.Q"mxo
*/ F1R91V|
publicList getUserByPage(Page page)throws sl|s#+Z
_3tHzDSG#
HibernateException {
m3
;
String querySentence = "FROM user in class HKq 2X4J$
@8Drhx
com.adt.po.User"; 7Upm
Query query = getSession().createQuery YS,kjL/
v83uGEq(
(querySentence); shxr^
query.setFirstResult(page.getBeginIndex()) KSVIX!EsX
.setMaxResults(page.getEveryPage()); (}O)pqZ>
return query.list(); a*CP1@O
} >h<eEv/
f2_LfbvH
} UA{sUj+?
# j*$ `W;
!$AVlMnJ
J"|)?$d]z
r\vB-nJ
至此,一个完整的分页程序完成。前台的只需要调用 K7<'4i~k
jd l1Q<Z
userManager.listUser(page)即可得到一个Page对象和结果集对象 Vv'
e,m
MTb}um.($
的综合体,而传入的参数page对象则可以由前台传入,如果用 n)} J<
>NB}Bc
webwork,甚至可以直接在配置文件中指定。 CSc*UX+
_@;2h`q ?
下面给出一个webwork调用示例: <?52Svi}}
java代码: -QIcBzw;q
BQSA;;n]
yt>Pf<AI
/*Created on 2005-6-17*/ yNc>s/
package com.adt.action.user; <Nvw
w
-6~*:zg,
import java.util.List; Sn.I
]:l
seHwn'Jn
import org.apache.commons.logging.Log; E{T\51V]%
import org.apache.commons.logging.LogFactory; GWjKZ1p
import org.flyware.util.page.Page; Jkpw8E7
XZcsx
import com.adt.bo.Result; uA
C:&
import com.adt.service.UserService; h\'GL(?DBI
import com.opensymphony.xwork.Action; H24g+<Tv
6\ux;lksn*
/** vc6UA%/f
* @author Joa -c<<A.X
*/ @M#2T
publicclass ListUser implementsAction{ D> Z>4:EM
Q+mMpI
privatestaticfinal Log logger = LogFactory.getLog ZyCAl9{p
;07!^#:L=Q
(ListUser.class); ;DC0LJ
au"HIyi?k
private UserService userService; P:lvZ
kSU5
}
private Page page; KrMIJA4>
H4l:L(!D
privateList users; bw%1*;n)
T 6QnCmB4
/* dadOjl)S)
* (non-Javadoc) aU^>kRGc
* /T#<g:
* @see com.opensymphony.xwork.Action#execute() [w=x 0J&
*/ bQXxb(^
publicString execute()throwsException{ 6$ IXER
Result result = userService.listUser(page); C$*`c6R
page = result.getPage(); [7<X&Q
users = result.getContent(); zmr=iK
return SUCCESS; ^+`vh0TPQ
} &@dMk4BH<
,Lv}Xku
/** c::x.B"w
* @return Returns the page. Lom%eoH)
*/ y{u6t 3
public Page getPage(){ yl 0?Y
return page; O b8[P=
} 3;>(W
FT|*~_@
/** 0p2 0Rt
* @return Returns the users. QMtt:f]?i
*/ {)b`fq
publicList getUsers(){ 'Dat.@j
return users; LWVO%@)w
} wW%I < M
`W]a
@\EYA
/** iS=T/<|?
* @param page 30DpIkf
* The page to set. /;OJ=x3i
*/ N"r ;d+LTL
publicvoid setPage(Page page){ '/sc `(`:0
this.page = page; m9L+|r
} H~ks"D1
M<ad>M
/** T^sxR4F
* @param users YvYav d
* The users to set. >F+:ej
*/ bzJKoxU
publicvoid setUsers(List users){ 6:B5PJq
this.users = users;
A:D\!5=
} *s%s|/
6,@M0CX
/** N.64aL|1
* @param userService 'h81\SKFK9
* The userService to set. >hQR
*/ J&3;6I
&
publicvoid setUserService(UserService userService){ 3M@>kIT8
this.userService = userService; +uT=Wb \
} W/\7m\B
} Ix(4<s
dHp6G^Y
L1F){8[
s &.Z;X
il#rdJ1@t
上面的代码似乎看不出什么地方设置了page的相关初值,事实上, e<p$Op
&McmA
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 _Jp_TvP>
qHKZ5w
么只需要: ItRGq
java代码: 'R'>`?Nh
w}YHCh
RtIc:ym
<?xml version="1.0"?> 9723f1&Vd
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork {>+$u"*
%kc g#p+tE
1.0//EN" "http://www.opensymphony.com/xwork/xwork- RU{}qPs?
1B1d>V$*
1.0.dtd"> TuF:m"4
B"qG-ci
<xwork> 5=?&q 'i
<;XJ::d
<package name="user" extends="webwork- ]!A;-m
K[ \z'9Q
interceptors"> %]R#}amW
`Ch6"=t
<!-- The default interceptor stack name P\M+ZA ;
8odVdivh
--> HhpP}9P;
<default-interceptor-ref @i`gR%
~Fx[YPO,
name="myDefaultWebStack"/> <pE G8_{}
o?b%L
<action name="listUser" ;T_9;RU<'b
AH7k|6ku<*
class="com.adt.action.user.ListUser"> fg1y@Dj/&
<param )ld7^G
%/^d]#
name="page.everyPage">10</param> #>,cc?H-
<result 1z`,*eD7
!;xE7w
name="success">/user/user_list.jsp</result> }Sh-4:-D
</action> ?k3b\E3
AzV5Re8M
</package> wH`@r?&
$`oA$E3
</xwork> ?UxY4m%R;
cpy"1=K~M
9F-k:hD |
oby*.61?5l
;+jp,( 7
{jVFlKP>
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 \8$`:3,@
=;`YtOL
了。并可以通过随意修改配置文件来修改每页需要显示的记录数。 J{Ay(
Cn55%:
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 [x)e6p)
yjr@v!o
m3WV<Cbz
w\mF2h
N<{`n;
我写的一个用于分页的类,用了泛型了,hoho BmM,vllO
esHiWHAC
java代码: x L BG}C
q)~qd$yMS
`u}x:f !
package com.intokr.util; #.><A8J
9?:S:Sq
import java.util.List; J#kdyBmuO
w*
I+~o-
/** toWmm(7v
* 用于分页的类<br> ZX0c_Mk=
* 可以用于传递查询的结果也可以用于传送查询的参数<br>
j{^(TE
* 3dbf!
* @version 0.01 VZ,T`8"
* @author cheng &8pXkD#A
*/ 3/AUV%+
public class Paginator<E> { .$k"+E
privateint count = 0; // 总记录数 ZFON]$Zk
privateint p = 1; // 页编号 IBqY$K+l
privateint num = 20; // 每页的记录数 /OP*ARoC21
privateList<E> results = null; // 结果 'l:2R,cP
Cm4*sN.&)
/** A1q^E(}O
* 结果总数 P&GZe/6Y
*/
p4t)Z#0
publicint getCount(){ sfV.X:ev
return count;
=l(JJ
} *p3P\ H^5
SSXS
publicvoid setCount(int count){ d0B+syl&4l
this.count = count; eTc`FXw`
} v2{O67j}
o
k~R[5W|'
/** [FL I+;gY
* 本结果所在的页码,从1开始 /4?`F}7)
* ]cr;PRyv
* @return Returns the pageNo. =#tQIhX`
*/ s2v*
publicint getP(){ b8>9mKs
return p; ddP,_.0
} a%!XLyq
^{s0d+@{
/** ~Z2eQx
jtM
* if(p<=0) p=1 PR?clg=z
* C6w{"[Wv=X
* @param p f
99PwE(=
*/ <<6w9wNon
publicvoid setP(int p){ }/spo3,6
if(p <= 0) e{;e
p = 1; b0X[x{k"
this.p = p; ^0Q*o1W
} yxN!*~BvL
\zU5G#LQ
/** d*$<%J
* 每页记录数量 5@$4.BGcF
*/ / yi :Q0
publicint getNum(){ a1SOC=.M;
return num; K]8wW;N4
} l*Ei7 |Z
<&:&qngg
/** 8>q%1]X
* if(num<1) num=1 P@YL.'KU)
*/ *]WXM.R8
publicvoid setNum(int num){ LFyceFbm
if(num < 1) l7,qWSsnK
num = 1; Zk
UuniO
this.num = num; uR@`T18
} Qiw4'xQm
7[BL 1HI*
/** |nN/x<v
* 获得总页数 io7U[ #
*/ C-u/{CP
publicint getPageNum(){ Ok&>[qu
return(count - 1) / num + 1; HY;?z`=
} %uVJLz
Lc<xgN+cJ
/** /dt!J
`:
* 获得本页的开始编号,为 (p-1)*num+1 L59oh
*/ |ozoc"'
publicint getStart(){ _M[[vXH
return(p - 1) * num + 1; WgJAr73
l
} q_y,j&
DXW?;|8)O
/** 8$ZSF92C
* @return Returns the results. 1lyOp
*/ I<./(X[H:#
publicList<E> getResults(){ ^r*%BUU9]%
return results; Gr$*t,ZW
} nFnF_
`l2<
public void setResults(List<E> results){ otf%kG w
this.results = results; ll\^9
4]Q
} k(z<Bm
xg,]M/J
public String toString(){ NK9WrUj)
StringBuilder buff = new StringBuilder |4.o$*0Y
gkML .u
(); ](>7h_2B
buff.append("{"); Xm:=jQn
buff.append("count:").append(count); iWM7,=1+
buff.append(",p:").append(p); c4>sE[]
buff.append(",nump:").append(num); .xkV#ol
buff.append(",results:").append KHecc/,,S
8@yc}~8 *
(results); LQ\
ELJj
buff.append("}"); VnSj:LUD
return buff.toString(); 4Sstg57x~
} 8o7]XZE=)
-*hb^MvP
} R``VQ
9LO.8Jy
}
ndvV~*1