Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 [xsiSt?6
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 O/2Jz
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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 vAp?Zl?g
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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$^+;j
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分页支持类: *<nfA}
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java代码: Ffp<|2T2_
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package com.javaeye.common.util; fnm:Wa|,%|
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import java.util.List; vs~lyM/
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publicclass PaginationSupport { E)7ODRVbl
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publicfinalstaticint PAGESIZE = 30; \9t6#8
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privateint pageSize = PAGESIZE; nmrYB w>
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privateList items; ,"W.A
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privateint totalCount; Du2v,n5@
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privateint[] indexes = newint[0]; vAMr&[
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privateint startIndex = 0; J6Q}a7I#
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public PaginationSupport(List items, int dECH/vJ^
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totalCount){ cWA$O*A
setPageSize(PAGESIZE); =wy 3h0k^
setTotalCount(totalCount); ^."HD(
setItems(items); c_r&)8
setStartIndex(0); `e!hT@Xxa
} "gPAxt
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public PaginationSupport(List items, int MjHjL~Tg
uJ! yM;{+
totalCount, int startIndex){ wzRIvm{
setPageSize(PAGESIZE); Q5s?/r
setTotalCount(totalCount); Xqac$%[3
setItems(items); S(f V ,;Z
setStartIndex(startIndex); 8?7gyp!k_f
} Ag!#epi{0
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public PaginationSupport(List items, int a~-^$Fzgy
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totalCount, int pageSize, int startIndex){ hsUP5_
setPageSize(pageSize); T?Dq2UW
setTotalCount(totalCount); \#A=twp
setItems(items); +i[w& P
setStartIndex(startIndex); Xkv+"F=-
} Qb|.;_
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publicList getItems(){ &Tf R].
return items; S}hg*mWn{$
} [n_H9$
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publicvoid setItems(List items){ Y{8L ~U:
this.items = items; ^8V cm*
} U&|$B|[
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publicint getPageSize(){ o\luE{H
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return pageSize; (qP !x 2j
} dIo|i,-
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publicvoid setPageSize(int pageSize){ d.7Xvx0Yww
this.pageSize = pageSize; p ?HODwZ
} ibOXh U
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publicint getTotalCount(){ swDSV1alMB
return totalCount; 6L6 Lk
} !!c.cv'
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publicvoid setTotalCount(int totalCount){ TLL.Ch|#Y
if(totalCount > 0){ e< Ee2pGX
this.totalCount = totalCount; Z6cG<,DQ
int count = totalCount / YSuwV)Y
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pageSize; IpxFME%!
if(totalCount % pageSize > 0) Q#bFW?>y,
count++; )W@H
indexes = newint[count]; y^ C;?B<
for(int i = 0; i < count; i++){ *4zVK/FJ
indexes = pageSize * "z }bgy
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i; FVsNOU
} |yI?}zyR
}else{ ^yRCR] oT
this.totalCount = 0; WPE@yI(
} \~
} oh;F]*k6
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publicint[] getIndexes(){ ^3`98y.Q
return indexes; `.dTkL
} ^}8_tZs8\
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publicvoid setIndexes(int[] indexes){ uF T\a=
this.indexes = indexes; ^;YD3EZw
} P|.KMtG
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publicint getStartIndex(){ nm'm*sU\
return startIndex; @D"1}CW
} S$"A[
#k=!>%+E
publicvoid setStartIndex(int startIndex){ f|VP_o<
if(totalCount <= 0) CRWO R pP
this.startIndex = 0; :;"3k64
elseif(startIndex >= totalCount) ,`|KNw5
this.startIndex = indexes d*3R0Q|#{
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[indexes.length - 1]; qRB7I:m-Wi
elseif(startIndex < 0) vfhip"1
this.startIndex = 0; Qb# S)[6s+
else{ V!KtF
this.startIndex = indexes y&__2t^u
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[startIndex / pageSize]; ==(M
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} c_^H;~^rL
} `p^M\!h*O
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publicint getNextIndex(){ =GR
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int nextIndex = getStartIndex() + '~ ]b;nA
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pageSize; kd\yHI9A
if(nextIndex >= totalCount) Mdwh-Cis/
return getStartIndex(); lQ+-g#`
else >5 5/@+^
return nextIndex; Q)a*bPz
} *rEW@06^\
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publicint getPreviousIndex(){ g1J]z<&
int previousIndex = getStartIndex() - f\(K ou$
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pageSize; P6=|C;[
if(previousIndex < 0) >Ft jrEB
return0; 5WZLB =
else 2N,*S
return previousIndex; \+Cp<Hv+
} xDlC]loi7
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} -`?V8OwY]
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抽象业务类 jA]xpf6}
java代码: v5$zz w
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/** Yp
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* Created on 2005-7-12 |R[m&uOib
*/ YT:5J%"
package com.javaeye.common.business; .HtDcGp
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import java.io.Serializable; vOP[ND=T
import java.util.List; ohh 1DsB
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import org.hibernate.Criteria; =q"3a9pb7
import org.hibernate.HibernateException; ?)PcYrV
import org.hibernate.Session; ss2:8up 99
import org.hibernate.criterion.DetachedCriteria; 6% ,Q
import org.hibernate.criterion.Projections; QnGJ4F
import } M~AkJL
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org.springframework.orm.hibernate3.HibernateCallback; dvj`%?=
import ,,iQG' *
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org.springframework.orm.hibernate3.support.HibernateDaoS '/p5tw8
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upport; E|fPI u
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import com.javaeye.common.util.PaginationSupport; . }1!MK5
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public abstract class AbstractManager extends 3~S~)quwP
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HibernateDaoSupport { "{:*fI;!
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privateboolean cacheQueries = false; ~gAx
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privateString queryCacheRegion; R`<E3J\*
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publicvoid setCacheQueries(boolean z DK+8
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cacheQueries){ 3whyIXs
this.cacheQueries = cacheQueries; FPMW"~v
} Ar$LA"vu4
P"#^i<ut@T
publicvoid setQueryCacheRegion(String Av[jFk
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queryCacheRegion){ ':[y]ep(~|
this.queryCacheRegion = _8`|KY
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queryCacheRegion; bC{~/ JP
} &vn9l#\(
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publicvoid save(finalObject entity){ HvngjP{>
getHibernateTemplate().save(entity); I[|I\tW
} ls5S9R 5
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publicvoid persist(finalObject entity){ "N;|~S)w!
getHibernateTemplate().save(entity); S,v`rmI
} - t+Mh.
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publicvoid update(finalObject entity){ &0"`\~lA
getHibernateTemplate().update(entity); +(<f(]bG
} TvP# /qGgG
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publicvoid delete(finalObject entity){ R}]FIu
getHibernateTemplate().delete(entity); KXGs'D
} c2U>89LlZ
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publicObject load(finalClass entity, I@B7uFj
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finalSerializable id){ Ob6vg^#
return getHibernateTemplate().load ~DD/\V
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(entity, id); nGt8u4gcP
} w*}9;l
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publicObject get(finalClass entity, JB|I/\(A
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finalSerializable id){ (!b:
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return getHibernateTemplate().get 6IX!9I\sT
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(entity, id); gM*s/,;O"
} Vh<`MS0X
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publicList findAll(finalClass entity){ YJy*OS_&
return getHibernateTemplate().find("from HT&0i,`
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" + entity.getName()); =
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} jmFN*VIL
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publicList findByNamedQuery(finalString >g[W@FhT'k
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namedQuery){ a:fHTU=\p
return getHibernateTemplate 2
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().findByNamedQuery(namedQuery); ~g{,W
} H@zk8]_P
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publicList findByNamedQuery(finalString query, w# e'K-=
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finalObject parameter){ (Ka#6
return getHibernateTemplate CytpL`&^]
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().findByNamedQuery(query, parameter); "|.(yN
} Bag#An1
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publicList findByNamedQuery(finalString query, gy{a+Wbc*
@I&"P:E0F;
finalObject[] parameters){ =Wf@'~K0k"
return getHibernateTemplate `T70FsSJ
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().findByNamedQuery(query, parameters); #-;BU{3*
} D}T,z
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publicList find(finalString query){ BGX@n#:
return getHibernateTemplate().find }]I?vyQ#V
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(query); K288&D|1WU
} yShHFlO=
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publicList find(finalString query, finalObject sYXS#;|M
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parameter){ lQ/XJw
return getHibernateTemplate().find 'T[zh#v>S
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(query, parameter); sD8S2
} ]lUu%<-;
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public PaginationSupport findPageByCriteria RY{tX`
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(final DetachedCriteria detachedCriteria){ x/=j$oA
return findPageByCriteria D@^ZpN8r
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); /<0D
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} rHlF& ET
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public PaginationSupport findPageByCriteria GcR`{ 3hO
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(final DetachedCriteria detachedCriteria, finalint c*dww
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startIndex){ Gq*)]X{Ua
return findPageByCriteria E0Q"qEvU
R(sM(x5a`
(detachedCriteria, PaginationSupport.PAGESIZE, 0?SLRz8
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startIndex); :,m)D775S
} j&A3s{S4A
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public PaginationSupport findPageByCriteria KIo}Gd&
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(final DetachedCriteria detachedCriteria, finalint Yys~p2
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pageSize, =[JN'|Q+
finalint startIndex){ |lxy< C4V
return(PaginationSupport) |a{]P=<q
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getHibernateTemplate().execute(new HibernateCallback(){ au|^V^m
publicObject doInHibernate 9Yyg}l:
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(Session session)throws HibernateException { C8E C?fSQ
Criteria criteria = N;'HR)
s.` d<(X?
detachedCriteria.getExecutableCriteria(session); T3./V0]\I
int totalCount = G%!\ p:w
8%<`$`FyU
((Integer) criteria.setProjection(Projections.rowCount 8/"|VE DOr
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()).uniqueResult()).intValue(); gvNZrp>e!
criteria.setProjection -j_I_
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(null); |xZcT4
List items = mE`qvavP|/
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criteria.setFirstResult(startIndex).setMaxResults R9h>I3F=c
{~fCqP.2
(pageSize).list(); 8e!DDh
PaginationSupport ps = VONAw3k7!
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new PaginationSupport(items, totalCount, pageSize, TE%#$q
4;RCPC
startIndex); mSzpRa
return ps; [fi'=Cb
} `uh@iD'KI
}, true); |<-F|v9og
} F,M"/hnPT
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public List findAllByCriteria(final ,6;xr'[o*
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DetachedCriteria detachedCriteria){ #we>75l{+R
return(List) getHibernateTemplate _]xt65TL
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().execute(new HibernateCallback(){ ]<T8ZA_Y;
publicObject doInHibernate Jh4&Qh|t
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(Session session)throws HibernateException { 0^_lj9B!
Criteria criteria = l(#ke
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detachedCriteria.getExecutableCriteria(session); dAr)%RZ
return criteria.list(); oL Vtu5
} qzA]2'~Q
}, true); &
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} 1@^Ek8C
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public int getCountByCriteria(final zLQ#GF
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DetachedCriteria detachedCriteria){ j-YJ."
Integer count = (Integer) a4(?]ND~6
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getHibernateTemplate().execute(new HibernateCallback(){ q|o|/ O-{
publicObject doInHibernate eR-=<0Iw;
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(Session session)throws HibernateException { nS+FX&_
Criteria criteria = *Z`XG_ s5
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detachedCriteria.getExecutableCriteria(session); o}MzqKfu
return Sf&?3a+f
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criteria.setProjection(Projections.rowCount QW~5+c9JJ
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()).uniqueResult(); g[s\~MF@s
} Z-SwJtWk
}, true); *SkiFEoD
return count.intValue(); j\'+wVyo
} px|>v8
} g TXW2S
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用户在web层构造查询条件detachedCriteria,和可选的 [.;%\>Qk<
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 N(:nF5>_
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PaginationSupport的实例ps。 H+VO.s.a
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ps.getItems()得到已分页好的结果集 HX3D*2v":
ps.getIndexes()得到分页索引的数组 ],\sRQbv&
ps.getTotalCount()得到总结果数 IAP/G5'Q
ps.getStartIndex()当前分页索引 C[xJU6z
ps.getNextIndex()下一页索引 1t~FW-:
ps.getPreviousIndex()上一页索引 Y .
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 ]bTzbu@
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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 m']9Q3-
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一下代码重构了。 N^h|h
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我把原本我的做法也提供出来供大家讨论吧: t/KcXM
<E>7>ZL
首先,为了实现分页查询,我封装了一个Page类: 5=Kq@[(4
java代码: C}mYt/
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/*Created on 2005-4-14*/ |P~O15V*Q
package org.flyware.util.page; GS
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/** 3s` V)aXP
* @author Joa =Kc|C~g
* /!=U+X
*/ /"""z=q
publicclass Page { ]}z'X!v_@
I %|@3=Yc
/** imply if the page has previous page */ %cH8;5U40
privateboolean hasPrePage; |XKOXa3.
7_9+=.
+X5
/** imply if the page has next page */ Hp btj
privateboolean hasNextPage; C-llq`(d
R=-+YBw7/
/** the number of every page */ *8$>Whr
privateint everyPage; X"h%tsuw
-7>^
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/** the total page number */ `"a? a5]k
privateint totalPage; 8P,l>HA
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/** the number of current page */ iH-bo@
privateint currentPage; 2E$^_YT
C
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/** the begin index of the records by the current z)4UMR#b&
;>NP.pnA)
query */ 9wL!D3e
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privateint beginIndex; P+Wm9xR2d
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/** The default constructor */ UTZ776`S&X
public Page(){ `6&`wKz
~Fy`>*
} P}HC(S1
Y!SE;N&
/** construct the page by everyPage \V]t!mZ-}l
* @param everyPage tY/En-&t
* */ \UQ9MX _
public Page(int everyPage){ ;\N79)Gk
this.everyPage = everyPage; /"=29sWB
} Bk,2WtVX
r"R(}`<,
/** The whole constructor */ ]>5T}h
public Page(boolean hasPrePage, boolean hasNextPage, 9%sFJ
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int everyPage, int totalPage, *kP;{Cb`
int currentPage, int beginIndex){ 8tU>DJ}0
this.hasPrePage = hasPrePage; mge#YV::
this.hasNextPage = hasNextPage; HmvsYP66
this.everyPage = everyPage; hM?`x(P
this.totalPage = totalPage; i8K_vo2Z)
this.currentPage = currentPage; '|Qd0,Z
this.beginIndex = beginIndex; _B)s=Snx
} 2Kjrw;
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/** dUIqD l
* @return |2O')3p"9
* Returns the beginIndex. xcst<=
*/ Us'Cs+5XcG
publicint getBeginIndex(){ 4S tjj!ew
return beginIndex; 0; 7#ji
} Z a!
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/** U_]=E<el
* @param beginIndex B`i$Wt<7
* The beginIndex to set. j_p`Ng
*/ !x>,N%~
publicvoid setBeginIndex(int beginIndex){ 69>/@<
this.beginIndex = beginIndex; ymYBm:"
} 80C(H!^
kVd5,Qd
/** 0Z"s_r}h
* @return jgG$'|s}
* Returns the currentPage. 6D|p Qs
*/ /hL\,x2
publicint getCurrentPage(){ g0PT8]8
return currentPage; Xx_tpC?
} A_Rrcsl4
9TC)
w|
/** Lbcy:E*g
* @param currentPage k@yh+ v5
* The currentPage to set. ,]ga[
*/ =NadAyv
publicvoid setCurrentPage(int currentPage){ D93gH1z
this.currentPage = currentPage; =J](.78
} *r;xw
Vz{>cSz#
/** O5zE {#
* @return @o6R[5(
* Returns the everyPage. {?Od{d9
*/ b]T@gJ4H=
publicint getEveryPage(){ YScvyh?E
return everyPage; >p0KFU
} 8] `Ru5nd
/ 2xSNalC
/** nq1
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* @param everyPage b?8)7.{F{
* The everyPage to set. 1fH<VgF`
*/ sef]>q
publicvoid setEveryPage(int everyPage){ /N6}*0Ru
this.everyPage = everyPage; X d3}Vn=
} Zyu/|Og
wPX*%0]
/** 8#w)X/
* @return ##cnFQCB
* Returns the hasNextPage. &dr@6-xaq
*/ i)MEK#{
publicboolean getHasNextPage(){ FH8k'Hxg
return hasNextPage; {WQq}-(
} y \D=Z
N@
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/** 1Ipfw
* @param hasNextPage Xh
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* The hasNextPage to set. D<>@
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*/ Ab2Q
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publicvoid setHasNextPage(boolean hasNextPage){ I-kWS4
this.hasNextPage = hasNextPage; 5wv fF.v
} BEUK}T K4
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/** V%*b@zv
* @return x6W`hpL
* Returns the hasPrePage. 1_hW#I\'
*/ cG{L
jt
publicboolean getHasPrePage(){ ?s2^zT
return hasPrePage; Su7bm1
} LHkQ'O0
=^tA_AxVw
/** +.kfU)6@
* @param hasPrePage U>a\j2I
* The hasPrePage to set. Jxa4hM0
*/ Yf}xwpuLk
publicvoid setHasPrePage(boolean hasPrePage){ g9~]s9
this.hasPrePage = hasPrePage; pDl3!m
} D=+NxR[
,eRQu.
/** TB!(('
* @return Returns the totalPage. T^:fn-S}=
* 4CrLkr
*/ O"Q7Rx
publicint getTotalPage(){ sOpep
return totalPage; <%P2qgz5
} D+RiM~LH8
y(iY
/** h&;t.Gdf
* @param totalPage nB5zNyY4
* The totalPage to set. kXrlSaIc
*/ }ptq
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publicvoid setTotalPage(int totalPage){ a`!@+6yC
this.totalPage = totalPage; ^5; `-Ky
} 2VoKr)
_>yoX
} lz<]5T|
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f-SuM% S_
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fH
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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 mJ}opy!{;
=1.9/hW
个PageUtil,负责对Page对象进行构造: bt$)Xu<R
java代码: ~}"]&%Q{J
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/*Created on 2005-4-14*/ 1P(&J
package org.flyware.util.page; U;q];e:,=}
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import org.apache.commons.logging.Log; %$5H!!~o
import org.apache.commons.logging.LogFactory; n6<V+G)T
SUM4Di7
/** #oni:] E!m
* @author Joa {Ui=b+
* T~:|!`
*/ 4\M.6])_
publicclass PageUtil { EYX$pz(x;
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privatestaticfinal Log logger = LogFactory.getLog p-SJ6Gg
9
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(PageUtil.class); alq%H}FF
vVl; |
/** tmUFT
* Use the origin page to create a new page kwpK1R4zs
* @param page BV#78,8(
* @param totalRecords [*:6oo98'
* @return v<Kmq-b
*/ U}k9 Py
publicstatic Page createPage(Page page, int E&$yuW^z
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totalRecords){ Q[F}r`
return createPage(page.getEveryPage(), ^vilgg~
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page.getCurrentPage(), totalRecords); :GpDg
} UMl#D>:C<
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/** $37
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* the basic page utils not including exception %ru;;h
,\2:/>2
handler E.|-?xQ6
* @param everyPage rgmF: C
* @param currentPage c(;a=n(E#
* @param totalRecords DwHF[]v'
* @return page ,Uhb
*/ >9e(.6&2XZ
publicstatic Page createPage(int everyPage, int G6@M&u5RT
=L;] ;i
currentPage, int totalRecords){ A+J*e
everyPage = getEveryPage(everyPage); _BdE<
!r
currentPage = getCurrentPage(currentPage); kHw_ S-
int beginIndex = getBeginIndex(everyPage, r$Co0!.
n_ lo`
currentPage); &e-U5'(6v_
int totalPage = getTotalPage(everyPage, r%:+$aIt
h\v'9
totalRecords); 1$qh`<\
boolean hasNextPage = hasNextPage(currentPage, ,1OyN]f3
c:Wze*vI;
totalPage); om?-WJI
boolean hasPrePage = hasPrePage(currentPage); |sRipWh
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returnnew Page(hasPrePage, hasNextPage, 26T "XW'_
everyPage, totalPage, ]e.JNo
currentPage, 5%sE]Y#
2MZCw^s>
beginIndex); Vq;dJ%sY
} 4vBL6!z:Z
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privatestaticint getEveryPage(int everyPage){ ;JZS^Wa
return everyPage == 0 ? 10 : everyPage; -46C!6a
} J+d1&Tw&
ok|qyN+
privatestaticint getCurrentPage(int currentPage){ V,rq0xW
return currentPage == 0 ? 1 : currentPage; fd-q3_f
} OO[F E3F
-'~LjA(
privatestaticint getBeginIndex(int everyPage, int <! )**
Hx,0zS%>
currentPage){ ~/.7l8)
return(currentPage - 1) * everyPage; $!&*xrrNM
} orOt>5}b<
y ]?V~%
privatestaticint getTotalPage(int everyPage, int 5j~$Mj`
.tD*2
totalRecords){ ?QE,;QtpK
int totalPage = 0; |2{wG4
>4t+:Ut:
if(totalRecords % everyPage == 0) UTXSeNP
totalPage = totalRecords / everyPage; g8PTGz
else B&D}F=U
totalPage = totalRecords / everyPage + 1 ; _h}kp\sps
`ZC<W]WYX/
return totalPage; y!!2WHvE
} L:@7tc.
+\v?d&.f0
privatestaticboolean hasPrePage(int currentPage){ pb~pN
return currentPage == 1 ? false : true; dAy?EO0\7
} Q-1vw6d
r Tz$^a}/
privatestaticboolean hasNextPage(int currentPage, OpHsob~
D_vbSF)
int totalPage){ 'C"9QfK
return currentPage == totalPage || totalPage == /Q~i~B 2j-
0jEL<TgC
0 ? false : true; n=[/Z!
} Yk=PS[f
"I(xgx*
>,td(= :
} hdrm!aBd
hP15qKy
W*2U="t
|P%Jw,}]9
>y,-v:Vy
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 %n*-VAfE\
D-c`FG'
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 'q`^3&E
cFJY^A
做法如下: 1YH+d0UGn
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 MG.`
r{5
Hro-d1J7
的信息,和一个结果集List: 4ecP*g
java代码: <)3u6Vky9
lv04g} W
soQ1X@"0
/*Created on 2005-6-13*/ >rf'-X4n
package com.adt.bo; |j,"Pl}il^
=uS9JU^E
import java.util.List; ;n
7/O5M|
w4gJoxY-`
import org.flyware.util.page.Page; >6?__v]9G
,k;^G><
=
/** [EKQR>s)
* @author Joa "yS _s
*/ P}4QQw
publicclass Result { .4E&/w+
.nVa[B|.
private Page page; BBev<
T
\_]^]>
private List content; }R{ts
\pVXimam
/** r4SXE\
G
* The default constructor #~
)IJ
*/ V{!J-nO
public Result(){ bJX)$G
super(); J|qZ+A[z
} ax<?GjpM
LA}Syt\F
/** 9@Jtaq>jf
* The constructor using fields Hhcpp7cr'
* rp;b" q
* @param page (^Y~/
* @param content i uF*.hc,%
*/ IhVO@KJI
public Result(Page page, List content){ vwxXgk
this.page = page; GJ_7h_4
this.content = content; QD0"rxZJ
} ?M\{&mlF
*=V~YF:Qb
/** 73/P&hT
* @return Returns the content. *Qg _F6y
*/ >LOjV0K/
publicList getContent(){ f}9zgWU
return content; f,kZ\Ia'r
} ']2E {V
mjW8Q\D
/** ]7Tkkw$
* @return Returns the page. YTUZoW2
*/ H}hiT/+$
public Page getPage(){ `)T13Xv
return page; KbA?7^zo`
} Utnr5^].2O
WE: 24b6
/** d?A
0MKnl
* @param content YoBDvV":@
* The content to set. \1^^\G>H5
*/ K<>oa[B9
public void setContent(List content){ 0Ziw_S\d&s
this.content = content; YS/Yd[ e
} hoK>~:;
v>Q#B
/** \1D<!k\S
* @param page RO 4Z?tz
* The page to set. e4?>-
*/ RBs-_o+ %
publicvoid setPage(Page page){ 2N: ,Q8~
this.page = page; [YlKR'_
} [XEkz#{
} ;DFSzbF`
snobT Q
`4=^cyt+
1_PoqD!q
&,{fw@#)_
2. 编写业务逻辑接口,并实现它(UserManager,
<G|(|E1
_`&m\Qe>
UserManagerImpl) `d5%.N
java代码: 1Q<^8N)pf
)u[emv$
A kC1z73<
/*Created on 2005-7-15*/ a7r%X -
package com.adt.service; ;f#v0W`5
PQ5QA61
import net.sf.hibernate.HibernateException; }dgfqq
4T|b
Cs?e
import org.flyware.util.page.Page; Oo5w?+t
`6~Aoe
import com.adt.bo.Result; "s0)rqf<
2$+bJJM
/** WW4vn|0v
* @author Joa v%+:/m1
*/ 7%Gwc?[x
publicinterface UserManager { 5:Z0Pt
;z}i-cNae
public Result listUser(Page page)throws B+\3-q
o<BOYrS
HibernateException; ?!A7rb/tj
YIoQL}pX
} GpY"fc%
#U!
_U+K
a,
k'Vk{
oHd FMD@
\2N!:%k
java代码: 2@'oe7E
v$7QIl_/7
,?8qpEG~#+
/*Created on 2005-7-15*/ ORe(]I`Z
package com.adt.service.impl; 7K,-01-:
_x%7@.TB
import java.util.List; 8!O5quEc
Ta
?_5
import net.sf.hibernate.HibernateException; Rdvk
ml@@
vQosPS_2L
import org.flyware.util.page.Page; \?[v{WP)
import org.flyware.util.page.PageUtil; LClNxm2X
cv998*|X:
import com.adt.bo.Result; `Q|*1
import com.adt.dao.UserDAO; [Dk=? +
import com.adt.exception.ObjectNotFoundException; KHe=O1 %QO
import com.adt.service.UserManager; OK[T3/v,
Uzz'.K(Mv|
/** rI= v
* @author Joa S%bCyK%p
*/ & ?h#Z!
publicclass UserManagerImpl implements UserManager { XewVcRo
g7}Gip}.>
private UserDAO userDAO; 1C}NQ!.
.k,1f*%
/** CtyoHvw+M
* @param userDAO The userDAO to set. ciBP7>'::
*/ +giyX7BPJ
publicvoid setUserDAO(UserDAO userDAO){ {@6=Q 6L
this.userDAO = userDAO; Wk~WOzr}^
} 0h#lJS*
_ky,;9G]
/* (non-Javadoc) _"?.!
* @see com.adt.service.UserManager#listUser %<k2#6K
v\KA'PmiP
(org.flyware.util.page.Page) EYtL_hNp}I
*/ cii_U=
public Result listUser(Page page)throws -~s!73pDY
jF ^~p9z
HibernateException, ObjectNotFoundException { msP{l^%0
int totalRecords = userDAO.getUserCount(); UtPLI al
if(totalRecords == 0) x2OaPlG,&V
throw new ObjectNotFoundException N4^-`
\|H!~) h$1
("userNotExist"); %eX{WgH
page = PageUtil.createPage(page, totalRecords); zMj#KA1
List users = userDAO.getUserByPage(page); En~5"yW5>]
returnnew Result(page, users); wW7eT~w
} f!\lg
Bc+w+
} qaY1xPWz"
veMH
/qMG=Z
AqWUwK9T
v*'^r)Q[p
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 LxYrl-
}SX,^|eN
询,接下来编写UserDAO的代码: pXrFljoYl[
3. UserDAO 和 UserDAOImpl: F<n3
java代码: ,F79xx9ufg
.Zn^Nw3
l==``
/*Created on 2005-7-15*/ Z>QF#."m
package com.adt.dao; +AR5W(&
^N7e76VwR
import java.util.List; AP68V
x.7]/)
import org.flyware.util.page.Page; ;XF:\<+
cJ{ Nh;"
import net.sf.hibernate.HibernateException; I;e=0!9U
&ib5*4!
/** ,5i` -OI
* @author Joa `bFff%_
*/ 0t Fkd
publicinterface UserDAO extends BaseDAO { dCE0$3'5
< vL,*.zd
publicList getUserByName(String name)throws v4u5yy_;(
2;zb\d
HibernateException; A0o-:n Fu
ti5mIW\
publicint getUserCount()throws HibernateException; GC>e26\:
2Z-ljD&
publicList getUserByPage(Page page)throws s8ywKTR-
LgKaPg$
HibernateException; _Tf4WFu2
/M|262%
} UYk/v]ZA
K?[q%W]%
xDG2ws=@D
+fC=UAZ
u$>4F|=T
java代码: /RNIIY~w
kW*f.!
RX>xB
/*Created on 2005-7-15*/ dYG,_ji
package com.adt.dao.impl; v'U{/ ,x
% 5m/
import java.util.List; fa++MNf}3
Ir
{OheJ
import org.flyware.util.page.Page; ruc++@J@
xAK6pDp
import net.sf.hibernate.HibernateException; lt
^GvWg
import net.sf.hibernate.Query; T^Y([23
[h^2Y&Au5
import com.adt.dao.UserDAO; M^O2\G#B
*C5R}9O5
/** ;1:Js0=;H
* @author Joa !B\R''J5
*/ ,VCyG:dw
public class UserDAOImpl extends BaseDAOHibernateImpl W{5#@_pL
{1IfU
implements UserDAO { ZX>AE3wk
%6t2ohO"
/* (non-Javadoc) \P j
* @see com.adt.dao.UserDAO#getUserByName !zkZQ2{Wn
u -;_y='m
(java.lang.String) eIz<)-7:
*/ :ctu5{"UJ
publicList getUserByName(String name)throws @CTgT-0!
Yn@lr6s
HibernateException { :K-~fA%kt?
String querySentence = "FROM user in class Q?nN!eT
W yB3ls~
com.adt.po.User WHERE user.name=:name"; qu-B|
MuOa
Query query = getSession().createQuery ~tBYIkvWT
{l>yi
(querySentence); N):tOD@B
query.setParameter("name", name); o$#G0}yn
return query.list(); 2>cGH7EBD
} 8.XoVW#
X.Rb-@
/* (non-Javadoc) /JHc! D
* @see com.adt.dao.UserDAO#getUserCount() J&M
o%"[)
*/ e8pG"`wM8
publicint getUserCount()throws HibernateException { F ~^Jmp7Y
int count = 0; `V`lo,"\
String querySentence = "SELECT count(*) FROM ht2\ y&si
'^No)n\`
user in class com.adt.po.User"; O_ChxX0KP
Query query = getSession().createQuery QWD'!)Zb
xD5:RE~g
(querySentence); L\@I*QP
count = ((Integer)query.iterate().next UJM1VAJ0
V8rx#H~
()).intValue(); fDT%!
return count; W8ouO+wK
} `-(|>5wWS
=T(6#"
/* (non-Javadoc) N>XS=2tzN
* @see com.adt.dao.UserDAO#getUserByPage $})g?Q
P!H_1RwXKC
(org.flyware.util.page.Page) *1v[kWa?
*/ q=%RDG+
publicList getUserByPage(Page page)throws ^lA=* jY(
[P&7i57
HibernateException { mS^tX i5hg
String querySentence = "FROM user in class KVT-P};jy*
A/u)# ^\
com.adt.po.User";
f4Xk,1Is
Query query = getSession().createQuery ?AJKBW^
7*
yzEM
(querySentence); *~t6(v?
query.setFirstResult(page.getBeginIndex()) v.pBX<
.setMaxResults(page.getEveryPage()); tnPv70m
return query.list(); j6Yy6X]
} @6wFst\t
yzerOL
} *M:B\D
n/Sw P
3QG7C{
%kS(LlL+6
)(ImLbM)
至此,一个完整的分页程序完成。前台的只需要调用 Hea;?4Vg
| N[<x@
userManager.listUser(page)即可得到一个Page对象和结果集对象 t5y;CxL
NWMFtT
的综合体,而传入的参数page对象则可以由前台传入,如果用 [R=yF ~-
3~uW I%I`
webwork,甚至可以直接在配置文件中指定。 GT0Of~?f
ldiD2
Q
下面给出一个webwork调用示例: Fs9I7~L3
java代码: "uaMk}[ <!
lfqiyYFm
t
m7^yn:
/*Created on 2005-6-17*/ f"%{%M$K
package com.adt.action.user; c(!6^qk]!`
]ooIrY8
import java.util.List; )}"wesNo".
_#r+ !e
import org.apache.commons.logging.Log; A-ZN F4
import org.apache.commons.logging.LogFactory; 7UdM
import org.flyware.util.page.Page; n/+.s(7c
mj9 <%P
import com.adt.bo.Result; }+C2I
import com.adt.service.UserService; H@%GSE
import com.opensymphony.xwork.Action; Uk^B"y_
(C@m Lu)
/** I@yCTluV$
* @author Joa K
i'Fn"
*/ !bN*\c
publicclass ListUser implementsAction{ X*{2[+<o
_$
+^q-
privatestaticfinal Log logger = LogFactory.getLog |4B:<x
<Bw^!.jAF
(ListUser.class); X!9 B2w
KX'{[7}m'
private UserService userService; *7ZN]/VRT
a1_GIM0
private Page page; AlAY iUw{
`HZ;NRr
privateList users; |}(`kW
FaDjLo2'o
/* mP0yk|
* (non-Javadoc) ,*7 (%k^`
* :lf+W
* @see com.opensymphony.xwork.Action#execute() rA%usaW
*/ -o$QS,
publicString execute()throwsException{ '}B+r@YCN
Result result = userService.listUser(page); Cjc6d4~
page = result.getPage(); Gn ~6X-l
users = result.getContent(); G!>z;5KuS
return SUCCESS; e\!0<d
} t!r A%*
ihIVUu-M
/** \=:~ki=@B
* @return Returns the page. eHn7iuS8
*/ <vONmE a
public Page getPage(){ __|+w<]
return page; .QZaGw=,z
} _qw?@478
#xX5,r0
/** Mxyb5h
* @return Returns the users. C71qPb|$R
*/ E4|jOz^j4\
publicList getUsers(){ w5A y)lz
return users; BD_Iz A<wK
} NQ(1
WtG~('g>&
/** @+Si?8\
* @param page BJM.iXU)[
* The page to set. `*_mP<Ag
*/ [lWQ'DZ
publicvoid setPage(Page page){ lDYyqG4
this.page = page; VF?<{F
} Y
}$/e
ow_W%I=6
/** {2=jAz'?
* @param users A OISs4
* The users to set. 9x>d[-#y:J
*/ -likj#Z
publicvoid setUsers(List users){ y\Ic@-aWI
this.users = users; m1B+31'>^
} b:lP%|7
Z4S!NDMm~
/** HCyv ]LR
* @param userService S ?{#r
* The userService to set. zsX1 QN16
*/ Z>)Bp/-
publicvoid setUserService(UserService userService){ X*/ho
this.userService = userService; wO'TBP
} YG@t5j#b
} w<Wf?a G
YG3J$_?y0
'gC_)rK*
kCR_tn
4
o4m\~as)Y
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, k5:G-BQ:
9
Vkb>yFX'
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 'p>Ra/4
mZSD(
么只需要: _jLL_GD
java代码: o]yl;I
QZ6D7tUc8
,l!Ta"
<?xml version="1.0"?> _FH`pv
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork B8f8w)m
`|{-+m
1.0//EN" "http://www.opensymphony.com/xwork/xwork- oW ::hB
"e.jZcN*
1.0.dtd"> 7
n8"/0kc:
fI&t]
<xwork> U>]$a71
&;^YBW :I
<package name="user" extends="webwork- }=<
YC++&Nk
interceptors"> Z/k:~%|E
kW;+|qs^
<!-- The default interceptor stack name #Y*X<L
kD=WO4}
--> ,{M^-3C
<default-interceptor-ref )'l:K.F
j[`j9mM8
name="myDefaultWebStack"/> n^Hm;BiE#
6 :b!F
<action name="listUser" &e @2
hs^zTZ_
class="com.adt.action.user.ListUser"> tSr8 zAV
<param oI
}VV6vO
?}wk.gt>
name="page.everyPage">10</param> 3EJj9}#x"'
<result G<}()+L
?zh9d%R
name="success">/user/user_list.jsp</result> A\4D79>x
</action> -ws? "_w
\k .{-nh
</package> B<5R
X{5vXT\/y
</xwork> S\:P-&dC
nyQ&f'<
wPQH(~k:
cG[l!Z
0)Uce=t`
8&GBV_`I
这样就可以通过配置文件和OGNL的共同作用来对page对象设置初值 4{y)TZ
\UPjf]&
了。并可以通过随意修改配置文件来修改每页需要显示的记录数。 _Gn2o2T
~xkeuU
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 )eUh=eW
&XIt5<$~R
[w0QZyUn
|XQIfW]A
'GNK "XA^
我写的一个用于分页的类,用了泛型了,hoho Bmr>n6|
uGwm
r
java代码: 6a[}'/
\H1(PA
u_@f$
package com.intokr.util; !hJ+Lp_
s^Y"' ` +
import java.util.List; $Q &lSVQ
K'L^;z6
/** r+A{JHnN
* 用于分页的类<br> Vc 1\i
* 可以用于传递查询的结果也可以用于传送查询的参数<br> ;O,+2VzP%^
* 7?#J~.d5
* @version 0.01 5x5@t
:
* @author cheng #eoome2Q
*/ ]O]4z,n
public class Paginator<E> { Z"/p,A9W9|
privateint count = 0; // 总记录数 uZNTHD
privateint p = 1; // 页编号 `g(Y*uCp
privateint num = 20; // 每页的记录数 U;YC}r
privateList<E> results = null; // 结果
[$mHv,~
{#ZlM
/** nEJq_
* 结果总数 L{X_^
*/ ^]H5h ]U'
publicint getCount(){ f86XkECZ;`
return count; |?!~{-o
} "Lzi+1
^H~h\,;zQ
publicvoid setCount(int count){ p*< 0"0
this.count = count; ASKf'\,dV
} ;y,5k?
3k\#CiB{
/** g2BHHL;`
* 本结果所在的页码,从1开始 F}F&T
* Lf16j*}-Q
* @return Returns the pageNo. sZjQ3*<-r
*/ G? ])o5
publicint getP(){ t>L;kRujVJ
return p; FtpK)9/4
} I4'5P}1yp
m,VOx7%n
/** =i$Fl{vH
* if(p<=0) p=1 X$HIVxyq2
* MX$0Op
* @param p !=pn77`g>
*/ $|L
Sx
publicvoid setP(int p){ 3DzMB?I
if(p <= 0) )Q=_0;#;k
p = 1; >tYm+coS
this.p = p; ohRjvJ'v|
} q3mJ782p]
v_BcTzQ0S
/** @:j}Jmg
* 每页记录数量 8NxM4$nQX
*/ B}n,b#,*
publicint getNum(){ |9u OUE
return num; 0@[$lv;OS
} 8*W#DH!
w{Ivmdto
/** ^hG-~z<
* if(num<1) num=1 UvJ}b
*/ @'w"R/,n-@
publicvoid setNum(int num){ :G [|CPm-
if(num < 1) QqDC4+p"
num = 1; VyXKZ%\dQ/
this.num = num; _G[g;$<
} i5en*)O8
~FZ&.<s
/** xu>9(,l
* 获得总页数 V_R@o3kv;
*/ xR-%L
publicint getPageNum(){ p?*Q- f
return(count - 1) / num + 1; iIvc43YV%
} 9%k2'iV7
zpzK>DH(
/** Cl5uS%g
* 获得本页的开始编号,为 (p-1)*num+1 zvvhFN2s
*/ $ZUdT
publicint getStart(){ "~#3&3HVS
return(p - 1) * num + 1; N,`$M.|?
} ,KF'TsFf
#pT"BSz]
/** Vrjc~>X
* @return Returns the results. -c_74c50
*/ viW!,QQ(S
publicList<E> getResults(){ ({
8-*
return results; Ar%%}Gx/
} 'vVQg
`n.5f[wC
public void setResults(List<E> results){ %oF}HF.
this.results = results; $I!XSz"/e
} _ q(ko/T
j:^#rFD4?
public String toString(){ 9`T)@Uj2n
StringBuilder buff = new StringBuilder HD@$t)mn
18)'c?^.
(); 3]OE}[R
buff.append("{"); o~U$GBg
buff.append("count:").append(count); H7?Vy bg~
buff.append(",p:").append(p); ++bf#qS<8D
buff.append(",nump:").append(num); v6[!o<@"a
buff.append(",results:").append c%^7!FSg
7G:s2432
(results); AhCW'.
buff.append("}"); g9m-TkNk
return buff.toString(); 4qphA9i1
} h(<,fg1
/vY(o1o
x
} _- [''(E
o906/5M
qPWP&k