Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 r|Zi3+
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 ?[1SiJT
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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 _n O.-
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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 .XH8YT42
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分页支持类: Yv\!vW7I
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java代码: )2j:z#'>
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package com.javaeye.common.util; i57(
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import java.util.List; x mo&![P
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publicclass PaginationSupport { otriif@+Z
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publicfinalstaticint PAGESIZE = 30; >;lKLGJrd>
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privateint pageSize = PAGESIZE; \+B?}P8N*l
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privateList items; VTw/_Hf2p
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privateint totalCount; rK=6]j(K
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privateint[] indexes = newint[0]; [MmM 9J["
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privateint startIndex = 0; L|67f4
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public PaginationSupport(List items, int g [L
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totalCount){ G11cNr>*
setPageSize(PAGESIZE); Bw-s6MS
setTotalCount(totalCount); qi\n] I
setItems(items); fM":f|
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setStartIndex(0); DrS?=C@
} *zQOJsg"e
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public PaginationSupport(List items, int M,..Kw/ }~
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totalCount, int startIndex){ o;;,iHu*
setPageSize(PAGESIZE); I~RcOiL)
setTotalCount(totalCount); w%u5<
setItems(items); WOb8"*OM
setStartIndex(startIndex); !sK#zAR2
} Xw(3j)xQ
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public PaginationSupport(List items, int 7A0dl}:
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totalCount, int pageSize, int startIndex){ "::9aYd!
setPageSize(pageSize); ^pw7o6}
setTotalCount(totalCount); lC{L6&T
setItems(items); <9N4"d!A
setStartIndex(startIndex); B1,?{Ur
} !E0fGh
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publicList getItems(){ gMay
return items; p">WK<N
} 'FxYMSZS$
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publicvoid setItems(List items){ ybYXD?
this.items = items; %&1$~m0
} Ij,Yuo
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publicint getPageSize(){ k(9s+0qe
return pageSize; kPedX
} `axQd%:AC
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publicvoid setPageSize(int pageSize){ "i(U
this.pageSize = pageSize; Di])<V
} QRiF!D)Nk
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publicint getTotalCount(){ 4K'|DO|dH
return totalCount; 2{gwY85:
} VLx T"]f
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publicvoid setTotalCount(int totalCount){ .W-=x,`hY4
if(totalCount > 0){ ]3 j[3'
this.totalCount = totalCount; wRj~Qv~E
int count = totalCount / x' ?.~
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pageSize; 9?!u2 o
if(totalCount % pageSize > 0) qs "s/$
count++; WQTendS
indexes = newint[count]; 4a1BGNI%SW
for(int i = 0; i < count; i++){ nE^wxtY
indexes = pageSize * T77)Np
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i; qjzZ}
} ,A^L=+
}else{ dZ-Ny_@&
this.totalCount = 0; )v};C<
} ud.poh~|
} #'#4hJ*YC
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publicint[] getIndexes(){ M Ey1~h/
return indexes; Fz{o-4
} ]m RF[b$
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publicvoid setIndexes(int[] indexes){ 1RmBtx\<
this.indexes = indexes; p-a]"l+L
} ^NcTWbs-T
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publicint getStartIndex(){ 20n%o&kG]8
return startIndex; =":@Foa
} HH+TjX/b
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publicvoid setStartIndex(int startIndex){ B6-AIPb
if(totalCount <= 0) `Uu^I
this.startIndex = 0; hcj{%^p
elseif(startIndex >= totalCount) :U7;M}0
this.startIndex = indexes {|G&W^`
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[indexes.length - 1]; 1a \=0=[
elseif(startIndex < 0) jBT*~DyN
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this.startIndex = 0; |.^^|@+
else{ r#ks>s
this.startIndex = indexes GcPB'`!M
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[startIndex / pageSize]; jc3ExOH
} g8C+1G8
} ytg7p 5{!i
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publicint getNextIndex(){ /M5=tW#e
int nextIndex = getStartIndex() + Z?vY3)
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pageSize; Z`e$~n(Bh
if(nextIndex >= totalCount) 0%v ixR52
return getStartIndex(); ,"4X&>_f
else ch%Q'DR_I)
return nextIndex; 5;r({J
} rjq -ZrC%
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publicint getPreviousIndex(){ 0tn7Rkiw
int previousIndex = getStartIndex() - qg/Y;tGSx
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pageSize; ":5~L9&G
if(previousIndex < 0) QSlf=VK*y
return0; Z3&XTsq
else U`},)$
return previousIndex; gME:\ud$
} X7(rg W8
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} ^v()iF
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抽象业务类 'dd<<E
java代码: F<XD^sO
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/** ;1Tpzm
* Created on 2005-7-12 M$E8:
*/ i1kh@s~8UC
package com.javaeye.common.business; 0:nt#n~_
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import java.io.Serializable; Wl}G[>P
import java.util.List; _ ;v_L
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import org.hibernate.Criteria; B%?|br
import org.hibernate.HibernateException; O>{t}6o
import org.hibernate.Session; #&HarBxx
import org.hibernate.criterion.DetachedCriteria; cc#_acR
import org.hibernate.criterion.Projections; *8(t y%5F0
import v:!7n
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org.springframework.orm.hibernate3.HibernateCallback; l"V8n BR`
import +b:h5,
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org.springframework.orm.hibernate3.support.HibernateDaoS mSqk[Ig\
knj,[7uh
upport; RaJ}>e
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import com.javaeye.common.util.PaginationSupport; #gr+%=S'6C
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public abstract class AbstractManager extends M`f;-
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HibernateDaoSupport { gEe W1:AB
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privateboolean cacheQueries = false; W.7d{
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privateString queryCacheRegion; 0DP%44Cv 9
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publicvoid setCacheQueries(boolean _yXeX
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cacheQueries){ jL[Is2<@
this.cacheQueries = cacheQueries; 9jJ/ RX p
} &B>uPZ]
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publicvoid setQueryCacheRegion(String %v6]>FNP'3
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queryCacheRegion){ (2a"W`
this.queryCacheRegion = 3qd-,qC
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queryCacheRegion; "vHAp55B{
} %BP)m(S7
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publicvoid save(finalObject entity){ 113x9+w[
getHibernateTemplate().save(entity); UHDI9>G~,
} X9BBnZ
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publicvoid persist(finalObject entity){ x~Esu}x7
getHibernateTemplate().save(entity); l+kg4y
} q\Io6=39x
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publicvoid update(finalObject entity){ @ %B!$\]
getHibernateTemplate().update(entity); R~?; KJ
} W;9X*I8f8
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publicvoid delete(finalObject entity){ [LEh
getHibernateTemplate().delete(entity); |~vQ0D
} <$Kv^Y *
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publicObject load(finalClass entity, ^+l\YB7pD
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finalSerializable id){ B*?PB]
return getHibernateTemplate().load X!+ a;wr
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(entity, id); tcdn"]#U
} V# %spW
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publicObject get(finalClass entity, ?cxK~Y\
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finalSerializable id){ Tsp-]-)
return getHibernateTemplate().get ,^Srd20
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(entity, id); HPH {{p
} ( #"s!!b
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publicList findAll(finalClass entity){ qxr&_r
return getHibernateTemplate().find("from ;l4\^E1
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" + entity.getName()); G&H"8REm
} _Cs}&Bic_
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publicList findByNamedQuery(finalString ;I@L
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namedQuery){ ~J{{n_G{
return getHibernateTemplate 6N)1/=)
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().findByNamedQuery(namedQuery); C7_T]e <
} TAoR6aE
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publicList findByNamedQuery(finalString query, F}DD;K
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finalObject parameter){ !QspmCo+
return getHibernateTemplate O;sQPG,v
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().findByNamedQuery(query, parameter); gQDK?aQX
} *?"{T;4u~O
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publicList findByNamedQuery(finalString query, I@M^Wu]wW
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finalObject[] parameters){ F
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return getHibernateTemplate k4rBS
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().findByNamedQuery(query, parameters); f~9Y1|6
} `{_PSzM
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publicList find(finalString query){ ,quTMtk~
return getHibernateTemplate().find .U%"oD
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(query); lHqx}n@e
} 0z#kV}wE
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publicList find(finalString query, finalObject O+j:L
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parameter){ ~ }22 Dvo
return getHibernateTemplate().find TMsoQ82
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(query, parameter); sdD[`#
} j@!}r|-T
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public PaginationSupport findPageByCriteria ^W'[l al.
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(final DetachedCriteria detachedCriteria){ %Ege^4PE
return findPageByCriteria NM.B=<Aw*
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); k;7.qhe:
} Y cpO;md
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public PaginationSupport findPageByCriteria qTF>!o#\:
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(final DetachedCriteria detachedCriteria, finalint 5 ZPUY
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startIndex){ zK?[dO
return findPageByCriteria Ao$z)<d'
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(detachedCriteria, PaginationSupport.PAGESIZE, yw!`1#3.
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startIndex); GR
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} 'bPo 5V|
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public PaginationSupport findPageByCriteria l.l~K%P'h
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(final DetachedCriteria detachedCriteria, finalint !yrHVc
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pageSize, &y\2:IyA
finalint startIndex){ i]pG}SJ
return(PaginationSupport) faX#KRpfd
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getHibernateTemplate().execute(new HibernateCallback(){ G[j79o
publicObject doInHibernate "s9gQAoaO
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(Session session)throws HibernateException { m28w4
Criteria criteria = ;(6lN<iU
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detachedCriteria.getExecutableCriteria(session); .+h
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int totalCount = 8Oh3iO
ped Yf{T
((Integer) criteria.setProjection(Projections.rowCount p5VSSvV\K
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()).uniqueResult()).intValue(); w[YbL2p
criteria.setProjection N)WG~=Gi
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(null); 1G.gPx[
List items = olxP`iK
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criteria.setFirstResult(startIndex).setMaxResults @A'1D@f#
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(pageSize).list(); yt:V+qdv
PaginationSupport ps = Fxx2vTV4ag
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new PaginationSupport(items, totalCount, pageSize, Hd`p_?3]
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startIndex); [qMdOY%jx
return ps; ?u!AHSr(
} R9G)X]
}, true); ^QR'yt3e
} 8w?\_P7QA
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public List findAllByCriteria(final _rd j,F8
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DetachedCriteria detachedCriteria){ C?|3\@7
return(List) getHibernateTemplate N4|q2Jvj6
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().execute(new HibernateCallback(){ }_l
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publicObject doInHibernate b7sE
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(Session session)throws HibernateException { %kFELtx
Criteria criteria = H<7DcwXv
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detachedCriteria.getExecutableCriteria(session); 13_~)V
return criteria.list(); T&"dBoUq>G
} sxwW9_C
}, true); w[oQ}5?9'
} yXo0z_ G
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public int getCountByCriteria(final q }v04Yy,o
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DetachedCriteria detachedCriteria){ %g@3S!lK
Integer count = (Integer) VSpt&19
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getHibernateTemplate().execute(new HibernateCallback(){ Dke($Jr{
publicObject doInHibernate C2=iZ`Z>T
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(Session session)throws HibernateException { xZ=FH>Y6'
Criteria criteria = ka)LK@p6
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detachedCriteria.getExecutableCriteria(session); ~73i^3yf
return 0ij~e<
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criteria.setProjection(Projections.rowCount !:O/|.+Vmf
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()).uniqueResult(); p@7i=hyt`p
} H;*a:tbxO+
}, true); >yA,@%X
return count.intValue(); `KJYm|@ i
} +fP/|A8P
} 7?!Z+r
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用户在web层构造查询条件detachedCriteria,和可选的 }EedHS
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startIndex,调用业务bean的相应findByCriteria方法,返回一个
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PaginationSupport的实例ps。 U.hERe~X
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ps.getItems()得到已分页好的结果集 MB8SB
ps.getIndexes()得到分页索引的数组 LE<u&9I\
ps.getTotalCount()得到总结果数 WE.$a t{*h
ps.getStartIndex()当前分页索引 5Q$r@&qp
ps.getNextIndex()下一页索引 1]
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ps.getPreviousIndex()上一页索引 5&?KW)6 Rz
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 b\?7?g
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,尤其是上面的示例代码,让我着实觉得该对我原来的分页查询做 &SjHrOG?
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一下代码重构了。 XVrm3aj(m
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我把原本我的做法也提供出来供大家讨论吧: vnC<*k4&v
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首先,为了实现分页查询,我封装了一个Page类: z/Ns5
java代码: 15xd~V?ai:
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/*Created on 2005-4-14*/ cBLR#Yu;O5
package org.flyware.util.page; j\`EUC
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/** "U%n0r2
* @author Joa Ml8 YyF/~
* Uvjdx(fY[a
*/ L$+d.=]
publicclass Page { eVw\v#gd
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/** imply if the page has previous page */ aO.\Qe+j
privateboolean hasPrePage; $J QWfGwR
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/** imply if the page has next page */ &1z)fD2
privateboolean hasNextPage; NP K#].F
A 1T<
/** the number of every page */ jM5_8nS&d
privateint everyPage; lx\qp`w
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/** the total page number */ }>MP{67Dm
privateint totalPage; Sa3I?+
R K"&l!o
/** the number of current page */ ]\CU9J|H8
privateint currentPage; T-4/d5D[
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/** the begin index of the records by the current !p}`kG
g%`i=s&N%
query */ ry.;u*F
privateint beginIndex; wYZT D*A2h
h ?uqLsRl
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/** The default constructor */ wgCvD
public Page(){ lj.nCV_
P DRnW
} vB[~pQ;Z
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/** construct the page by everyPage P
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* @param everyPage q`XW5VV{K
* */ (2UW_l
public Page(int everyPage){ ?2{bKIV_
this.everyPage = everyPage; `/z_rqJ0CL
} G+0><,S
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/** The whole constructor */ v @:~mwy
public Page(boolean hasPrePage, boolean hasNextPage, z"tjDP
=WC-Sj{I
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int everyPage, int totalPage, wZ#Rlv,3Wa
int currentPage, int beginIndex){ J , V
this.hasPrePage = hasPrePage; KkEv#2n
this.hasNextPage = hasNextPage; p8Iw!HE
this.everyPage = everyPage; !<&m]K
this.totalPage = totalPage; q# MM
this.currentPage = currentPage; x<)G( Xe*
this.beginIndex = beginIndex; #O"
} z"lqrSJ:
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/** blGf!4H
* @return :p' VbQZ{
* Returns the beginIndex. $(ewk):
*/ Y$g}XN*)E
publicint getBeginIndex(){ \i!Son.<
return beginIndex; 98fu>>*G{
} j Fma|y
3 t)v%S|k
/** 3\AM=`
* @param beginIndex qos`!=g?
* The beginIndex to set.
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*/ $J.T$0pFa
publicvoid setBeginIndex(int beginIndex){ sc W'AJJq
this.beginIndex = beginIndex; h>alGLN>
} BYi)j6"
XF|WCZUnY%
/** @wp4 |G
* @return z%1{
* Returns the currentPage. &-%X:~|:X
*/ Q/ZkW
publicint getCurrentPage(){ ,`32!i
return currentPage; eWvo,4
} XX6 T$pA6
_n"Ae?TP
/** >`'O7.R
* @param currentPage aE|OTm+@9;
* The currentPage to set. A5fwAB
*/ e8}Ezy"^
publicvoid setCurrentPage(int currentPage){ ow6*Xr8eQ
this.currentPage = currentPage; #?[.JD51l
} p@YB?#Im
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/** 7\XE,;4>
* @return &<5+!cV=
* Returns the everyPage. Sm-wH^~KA
*/ w!SkWS b,~
publicint getEveryPage(){ >u0w.3r#
return everyPage; PUdM[-zjh
} 0)!Ll*L!p
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/** O7t(,uox3y
* @param everyPage %."@Q$lA
* The everyPage to set. -n5
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*/ Nt:9 MG>1
publicvoid setEveryPage(int everyPage){ q
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this.everyPage = everyPage; 7@}$|u:JUF
} fP HLXg5s
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/** CHJ>{b`O
* @return awewYf$li
* Returns the hasNextPage. 3WY$WRv
*/ 17.x0gW,
publicboolean getHasNextPage(){ \5)h tL1F
return hasNextPage; !? 5U|
} wsU V;S*X%
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/** sJ
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* @param hasNextPage B;K`q
* The hasNextPage to set. X"fh@.
*/ C0*@0~8$9
publicvoid setHasNextPage(boolean hasNextPage){ ,)!u)wz
this.hasNextPage = hasNextPage; D4JLtB'=
} \C^;k%{LV
'R<&d}@P*#
/** 1xE]6he4{T
* @return ]iNEw9
* Returns the hasPrePage. @4$\
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*/ SJt<+kg
publicboolean getHasPrePage(){ llV3ka^!
return hasPrePage; I zbU)ud
} J[~5U~F
sbj(|1,ac
/** ^YdcAHjK
* @param hasPrePage YW@#91.
* The hasPrePage to set. bI)u/
*/ !HeSOzN
publicvoid setHasPrePage(boolean hasPrePage){ {gNV[45
this.hasPrePage = hasPrePage; JO<wK
} z7M_1%DEx
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/** hI?sOR!
* @return Returns the totalPage. C;QAT
* +ISz?~8
*/ 5]I| DHmu
publicint getTotalPage(){ v:Tzv^
return totalPage; ?{w3|Ef&
} 2&c9q5.b
;w|b0V6
/** W>VP'vn}
* @param totalPage VvFC -r,=G
* The totalPage to set. lv vs%@b>
*/ ;,i]w"*
publicvoid setTotalPage(int totalPage){ / N)W2
this.totalPage = totalPage; ac kqH+'
} P0H6mn*
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}
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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 `(A5f71MfM
U9D!GKVp
个PageUtil,负责对Page对象进行构造: 1+-_s
java代码: "&+"@<
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/*Created on 2005-4-14*/ V=fEPM
package org.flyware.util.page; Ig3;E+*>
2z\zh[(w
import org.apache.commons.logging.Log; nhIa175'
import org.apache.commons.logging.LogFactory; l;y7]DO
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/** n,B,"\fw
* @author Joa *@d&5
* `tjH<
*/ "\0v,!@
publicclass PageUtil { aK`@6F,]j
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privatestaticfinal Log logger = LogFactory.getLog JaB<EL-9r2
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(PageUtil.class); Us+pc^A
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/** ]4;PR("aU
* Use the origin page to create a new page aW!@f[%~F
* @param page JyR/1 W
* @param totalRecords 3;%5Yu
* @return x\Z'2?u}
*/ R(n^)^?
publicstatic Page createPage(Page page, int 5]M>8ll
a'!zG cT
totalRecords){ XJLQ{
return createPage(page.getEveryPage(), detwa}h[0
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page.getCurrentPage(), totalRecords); rj6#1kt
} *
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/** l x,"EOP
* the basic page utils not including exception qhT@;W/X
X^WrccNX
handler B" 3dQwQ
* @param everyPage
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* @param currentPage Yv:55+ e!|
* @param totalRecords v%fu
* @return page ;A#`]-i C
*/ =zyC-;r!
publicstatic Page createPage(int everyPage, int byv[yGa`
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currentPage, int totalRecords){ {'U
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everyPage = getEveryPage(everyPage); sP ls
zC[
currentPage = getCurrentPage(currentPage); =b/L?dR.-
int beginIndex = getBeginIndex(everyPage, rL}YLR
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P
currentPage); _cu:aktf2
int totalPage = getTotalPage(everyPage, YfRkwKjy(
S{Er?0wm.R
totalRecords); o`Ta("9^
boolean hasNextPage = hasNextPage(currentPage, &LbJT$}V
%Qj;, #z
totalPage); )KP5WudX
boolean hasPrePage = hasPrePage(currentPage); 4fe7U=# ;Y
p1vp8p
returnnew Page(hasPrePage, hasNextPage, gCxAG
everyPage, totalPage, |O"lNUW
currentPage, Ntbg`LGf'!
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beginIndex); s M +WkN}{
} $ibuWb"a
Ps 8%J;
privatestaticint getEveryPage(int everyPage){ d'Zqaaf k%
return everyPage == 0 ? 10 : everyPage; kcQ'$<Mz<
} xKFn.qFr
hiUD]5Kp
privatestaticint getCurrentPage(int currentPage){ 0X^Ke(/89
return currentPage == 0 ? 1 : currentPage; z(H^..<!5
} :hM/f
(7 r<''
privatestaticint getBeginIndex(int everyPage, int 1CHeufQ
Pcw6!xH
currentPage){ PTEHP
return(currentPage - 1) * everyPage; AhNq/?Q Q~
} KjQR$-
q=#}
yEG
privatestaticint getTotalPage(int everyPage, int 3JVK
El@(mOu|
totalRecords){ ;f"0~D2
int totalPage = 0; >Bgw}PI
t1%_DPD%W
if(totalRecords % everyPage == 0) vPD]hs
totalPage = totalRecords / everyPage; 2/0v B>
else SGe^ogO"v
totalPage = totalRecords / everyPage + 1 ; zF`c8Tsx])
WH= EPOR,
return totalPage; d`F&aC
} BN4_:
nG;8:f`
privatestaticboolean hasPrePage(int currentPage){ -*XCxU'
return currentPage == 1 ? false : true; FD8N"p
} =|YxDas
V?=8".GiX
privatestaticboolean hasNextPage(int currentPage, PZ*pQ=`
AqV7\gdOC
int totalPage){ dS<C@(
return currentPage == totalPage || totalPage == IzpZwx^3''
G;~V
0 ? false : true; Grk@dZI
} G^`1]?
ruazOmnn~
LH@j8YB5u
} -
h9?1vc7
n2fbp\ I
9t#S= DP
uECsh2Uin
#jxe%2'Ot
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+y&,N,
zBe8,, e
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 uI DuGrt
~PHB_cyth
做法如下: )}_a
0bt
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 *7wAkljP
[mPjP%{=@
的信息,和一个结果集List: Z>^pCc\lH
java代码: MKWyP+6`
4M^G`WA}t9
Z" uY}P3
/*Created on 2005-6-13*/ ,Uy|5zv
package com.adt.bo; .({smN,B
UF@XK">
import java.util.List; 17OH]
Y
"VY%S^
import org.flyware.util.page.Page; [l8jRT=R
J:kmqk!
/** iT)z_
* @author Joa q=9`06
*/ X B_B4X1R
publicclass Result { //4Xq8y
HX6Ma{vBk
private Page page; `Ps:d^8*P
[o<VVtB.Gk
private List content; 5e fpeu
}nMPSerE
/** +|ycvHd
* The default constructor 59Gk3frk(
*/ wW%4d
public Result(){ =lu/9
i6
super(); ?Sb8@S&J
} <Engi!
l3IWoa&sh
/** 1Zi,b
* The constructor using fields i}~SDY
* 51QRM32Y
* @param page SC-
$B
* @param content %DQhM ,c@
*/ KW7UUXL
public Result(Page page, List content){ :hI@AA>g
this.page = page; "XT"|KF|D
this.content = content; STJJU]H
} ZZyDG9a>7
q@jq0D)g
/** %~QO8q_7
* @return Returns the content. Wn>@9"
*/ "hQ_sgz[Z
publicList getContent(){ i:l<C
return content; ts8+V<g
} ~M(5Ho
MBXBog7U
/** bUY>st'
* @return Returns the page. W.w)H@]7m
*/ X7g3
public Page getPage(){ G5FaYL.7
return page; E{2Eoj;gq
} .E@|D6$D
UG<79"\i
/** NxLXm,
* @param content
kZ=s'QRgL
* The content to set. OK{xuX8u
*/ C8L'si
public void setContent(List content){ u1c%T@w>Lz
this.content = content; @EoZI~
} A?*o0I
$ F S_E
/** K2<~(78C
* @param page (S ^8UV
* The page to set. SZ_V^UX_
*/ YKa0H%B(
publicvoid setPage(Page page){ Tb1U^E:
this.page = page; O,.!2wVrN
} [qoXMuC|P
} :h1pBEiH
O0PJ6:9P
+B|7p9qy
J4YBqp
%AW4.3()8
2. 编写业务逻辑接口,并实现它(UserManager, Oi} T2I
Ap$y%6
UserManagerImpl) k'X;ruQ:tF
java代码: -!({BH-M_
j:bgR8%e
_U{&@}3
/*Created on 2005-7-15*/ {w
<+_++
package com.adt.service; CD0VfA>Z
.O0O-VD+a
import net.sf.hibernate.HibernateException; n$(p-po
7}_!
import org.flyware.util.page.Page; t]-uw-E
yE} dj)wd
import com.adt.bo.Result; *U#m+@\0
gLsU:aeCT
/** J`*iZvW#Bx
* @author Joa <:|3rfm#
*/ X_$a,"'~)
publicinterface UserManager { voe7l+Xk
drq hQ
public Result listUser(Page page)throws ~}DQT>7$
`)4a[thp
HibernateException; |3?
8)z\n
8p1ziz`4>$
} rbqo"g`
Fd\e*ww'
J g$xO@.
z{]?h cY
#2xSyOrmf
java代码: D,ly#Nn
+' oX
!8tS|C#2
/*Created on 2005-7-15*/ A 699FQ
package com.adt.service.impl; x6'^4y])
zX7q:Pt
import java.util.List; YH:8<O,{-
N6Z{BLZ
import net.sf.hibernate.HibernateException; %G3sjnI;l
_U)%kY8
import org.flyware.util.page.Page; <1~^C
import org.flyware.util.page.PageUtil; !Ngw\@f
q\9d6u=Gm
import com.adt.bo.Result; `&$B3)Eb
import com.adt.dao.UserDAO; ~=y3Gd
B3
import com.adt.exception.ObjectNotFoundException; Cef:tdk7
import com.adt.service.UserManager; z"F*\xa
l!IKUzt)7
/** X21dX`eMN
* @author Joa B>TSdn={>
*/ >E"9*:.^a
publicclass UserManagerImpl implements UserManager { v+1i=s2$
#^mqQRpgq
private UserDAO userDAO; #%S0PL"x U
eK`PxoTI-I
/** K3p@$3hQ
* @param userDAO The userDAO to set. Q1tpCT
*/ qs=tJ^<<o
publicvoid setUserDAO(UserDAO userDAO){ NO>k
this.userDAO = userDAO; 2Ji+{,?,
} d34Y'r
E,*&BDW
/* (non-Javadoc) xX@FWAj
* @see com.adt.service.UserManager#listUser &/ouW'oP
z \?UGxu}
(org.flyware.util.page.Page) Rf[V)x
*/ QD<eQsvV
public Result listUser(Page page)throws h[=nx^
F,v7ifo#f
HibernateException, ObjectNotFoundException { u3dsQU
int totalRecords = userDAO.getUserCount(); 3q &k
if(totalRecords == 0) ]h~o],:
throw new ObjectNotFoundException }e=e",eAT
YBSl-G'
("userNotExist"); YU\Gj S~>&
page = PageUtil.createPage(page, totalRecords); !dv-8C$U
List users = userDAO.getUserByPage(page); {j6g@Vd6lx
returnnew Result(page, users); D@vMAW
} &(O06QL
&=-PRza%j
} $A?}a
.s};F/(diD
xv0M
.fJ*c
6q%ed
UED
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 k|#Zy,
}[,3yfiX
询,接下来编写UserDAO的代码: /2h][zrZ[.
3. UserDAO 和 UserDAOImpl: c$#GM57V
java代码: KO-a; [/
~hD{coVTI
j)6G7T|
/*Created on 2005-7-15*/ uL>:tb
package com.adt.dao; ylkqhs&
m"-G6BKS
import java.util.List; dzxI QlP
9Dq.lr^
import org.flyware.util.page.Page; Ej|A
; &E
A\C'dZ <N
import net.sf.hibernate.HibernateException; 5&qY3@I7l
tw86:kYEz
/** NUu;tjt:
* @author Joa )l{A{f6O
*/ 1(pjVz&
publicinterface UserDAO extends BaseDAO { >
Z++^YVE
._ih$=
publicList getUserByName(String name)throws ^;64!BaK
Jy`G]]?
HibernateException; uWrFunh%
uTw|Q{ f
publicint getUserCount()throws HibernateException; CK Mv7
r./z,4A`
publicList getUserByPage(Page page)throws )"-fHW+fy
N&N 82OG
HibernateException; O,]_ tp
-3`Isv
} sZEgsrJh
1!f2*m
1:YAn
XqX
I(q^
b_l.QKk
java代码: uegb;m
uc\.oG;~q
FSVS4mtiX\
/*Created on 2005-7-15*/ @[0jFjK
package com.adt.dao.impl; [[&)cbv
s8yCC#H"
import java.util.List; w. vY(s
W'd/dKUx
import org.flyware.util.page.Page; CHg]U l
6_Fpca3L
import net.sf.hibernate.HibernateException; \ bC}&Iz6
import net.sf.hibernate.Query; @F~0p5I
pB[%:w/@l:
import com.adt.dao.UserDAO; =;g= GcVK
A
mvw`u>
/** C*$|#.l
* @author Joa N]V/83_
*/ yI lV[_
public class UserDAOImpl extends BaseDAOHibernateImpl v<%]XHN
wd"TM
implements UserDAO { M,ppCHy/$
FSFFk~
/* (non-Javadoc) {$3j/b
* @see com.adt.dao.UserDAO#getUserByName Cv0&prt
>QA/Mi~R
(java.lang.String) BQE{
*/ S ]vW&r3`
publicList getUserByName(String name)throws !+5C{Hs2
+_P8'e%Iy
HibernateException { <r0.ppgY
String querySentence = "FROM user in class _F3KFQ4,S-
r+SEw ;
com.adt.po.User WHERE user.name=:name"; *O!T!J
Query query = getSession().createQuery `!] R!T@C
_w\Y{(k
(querySentence); _r~!O$2
query.setParameter("name", name); 5XI;<^n2
return query.list(); / *AJ+K._
} `8mD7xsg$
-3u@hp_
/* (non-Javadoc) h=!M6yap<
* @see com.adt.dao.UserDAO#getUserCount() MJy;GzJ O
*/ f<'n5}{RO0
publicint getUserCount()throws HibernateException { U LV)0SB
int count = 0; $+A%ODv
String querySentence = "SELECT count(*) FROM +SAk:3.#CV
&b5T&-C<
user in class com.adt.po.User"; @X3 gBGY)
Query query = getSession().createQuery _{[k[]
"xL;(Fqu
(querySentence); W^5<XX,ON
count = ((Integer)query.iterate().next YCir Oge
}DJ|9D^yf
()).intValue(); aJEbAs}
return count; Lhl$w'r
} av'd%LZP
S`ax*`
/* (non-Javadoc) i_[^s:*T
* @see com.adt.dao.UserDAO#getUserByPage *?EO n -
sI^@A=.@
(org.flyware.util.page.Page) IOSuaLH^
*/ c-[Q,c
publicList getUserByPage(Page page)throws M(_^'3u
,Wz[tYL*
HibernateException { fO[Rf_
String querySentence = "FROM user in class #H'sZv
|WD,\=J2
com.adt.po.User"; 7p
P|
Query query = getSession().createQuery +io;K]C
2$o2.$i81
(querySentence); L4\SBO
query.setFirstResult(page.getBeginIndex()) 3~cS}N T
.setMaxResults(page.getEveryPage()); }2-[Ki yv
return query.list(); zAKq7'_=
} DQ}_9?3
1<XiD3H;
} a)I=U[
J0IdFFZ|w
gi1}5DR
Zp/qs
z(]
D=i0e8D!+
至此,一个完整的分页程序完成。前台的只需要调用 \SYPu,ZT
30sC4}
userManager.listUser(page)即可得到一个Page对象和结果集对象 IeRl6r%:
c,6<7
的综合体,而传入的参数page对象则可以由前台传入,如果用 -IpV'%nX;
o{ ,ba~$.w
webwork,甚至可以直接在配置文件中指定。 DBj;P|L_
a-z23$3
下面给出一个webwork调用示例: 4f@havFIJ
java代码: '0'"k2"vC
jw`&Np2Q
ROJ'-Vde9
/*Created on 2005-6-17*/ zPX=MfF
package com.adt.action.user; ;a!h.8UJPI
j6&zRFX
import java.util.List; ?`vM#)
-(4E
import org.apache.commons.logging.Log; NDs]}5#
import org.apache.commons.logging.LogFactory; _0DXQS\
import org.flyware.util.page.Page; p%1xj2 ?nN
wu&|~@_s@
import com.adt.bo.Result; C }h<ldlY
import com.adt.service.UserService; ^Ff~j&L@{
import com.opensymphony.xwork.Action; bWX[<rh'
bMK#^ZoH
/** 3/A[LL|
* @author Joa P-E'cb%ub
*/ I:uQB!
publicclass ListUser implementsAction{ oP|pOs\$p
;qT!fuN;
privatestaticfinal Log logger = LogFactory.getLog DWm;&RPJ
i(&6ys5
(ListUser.class); *6sJ*lh
x8SM,2ud
private UserService userService; O5G<O(,\
|mQtjo
private Page page; t[f9Z
ZZ]OR;8
privateList users; 4t%:O4
3e
"a0u-}/D
/* 7(|3 OR+
* (non-Javadoc) ig.6[5a\
* :N+#4rtgUY
* @see com.opensymphony.xwork.Action#execute() @??c<]9F
*/ Dvq*XI5
publicString execute()throwsException{ ard3yNQt
Result result = userService.listUser(page); !F7EAQn{(
page = result.getPage(); b68G&z>
users = result.getContent(); Zs3]|bUR
return SUCCESS; `:bvuc(
} #g-*n@
1
"j.oR}s9?#
/** ) v[Knp'
* @return Returns the page. u':0"5}
*/ FB=
public Page getPage(){ ?ck^? p7
return page; FkxhEat8
} @E"+qPp.3
x3I%)@-Z
/** KWigMh\r
* @return Returns the users. H s4zJk
*/ :AqnWy
publicList getUsers(){ \}4#**]
return users; -MHX1`P:Sn
} qK6
uU9z
X_tW#`
/** vVAZSR#
* @param page Pdo5sve
* The page to set. -B3wRAEt
*/ s=y9!rr
publicvoid setPage(Page page){ R0YC:rAt
this.page = page; {^$"/hj
} H:{(CY?t
K}5$;W#
/** c9g \7L,Z
* @param users TNyY60E
* The users to set. {z[HNSyRs
*/ *l?%
o{
publicvoid setUsers(List users){ YI),q.3X~
this.users = users; Kt* za
} zk 'e6
h'YcNkM
2>
/** C@?e`=9(
* @param userService =<FZ{4
* The userService to set. .IAHy)li"
*/ : .w'gU_
publicvoid setUserService(UserService userService){ RoM*Qjw
this.userService = userService; k#=leu"I
} ~tj7zI6
} {}_Oo%IVGK
8JFkeU%yO
%{VI-CQ
yYg&'3
"RJk7]p`*
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, DwrCysIK
2,e|,N"zN
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 &\]f!'jV
j&G~;(DY
么只需要: U/&qV"Ih
java代码: (_n8$3T75
o Jp_c
<$3nD b-
<?xml version="1.0"?> V_d%g<n4
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork
&lfF!
0?L$)T-B
1.0//EN" "http://www.opensymphony.com/xwork/xwork- >93{=+
3{LvKe
1.0.dtd"> C<=p"pWw
y`@4n.Q
<xwork> leYmVFE
A`/7>'k/q[
<package name="user" extends="webwork- +#db_k
BHE =Zo
interceptors"> Z!i'Tbfn
K$v Rk5U
<!-- The default interceptor stack name adE0oXQH"
EkAqFcKLq
-->
qmyZbo|8&
<default-interceptor-ref [^=8k2
+~k,4
name="myDefaultWebStack"/> L#@$Mtc
^yZSCrPGI
<action name="listUser" d@4=XSj
B;7s ]R
class="com.adt.action.user.ListUser"> 4wD^?S!p
<param (V?`W7
yWk:u 5
name="page.everyPage">10</param> 5h^qtK
<result B=/=U7T
] "vdC}
name="success">/user/user_list.jsp</result> g#3x)97Z
</action> kRa$jD^?
I%*Zj,>
</package> pR7G/]U$A
^O:RS
g9
</xwork> "Ksd9,J\b
W&[9x%Ba
9JeGjkG,
vjWgR9 4/{
evk
<<zi
(8F?yBu
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 U]&%EqLS
[~JN n
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。 B>L^XGq
iv`-)UsE
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 T js{
)r9
*hgsS~
cwU6}*_zn
1:V/['|*g)
@d9*<>@:
我写的一个用于分页的类,用了泛型了,hoho iU|C<A%Hh
U.)eJ1a
java代码: L7="! I
> _) a7%
fP*C*4#X
package com.intokr.util; 8u23@?
lsxii-#O
import java.util.List; ,FPgs0rrS
49>yIuG
/** a[#BlH
* 用于分页的类<br> Q'LU?>N)/
* 可以用于传递查询的结果也可以用于传送查询的参数<br> yZ6X$I:C
* @g?z>n
n
* @version 0.01 ,peFNpi
* @author cheng 3c"{Wu-}
*/ zy5bDL -
public class Paginator<E> { uu #+|ZD
privateint count = 0; // 总记录数 z}|'&O*.F
privateint p = 1; // 页编号 v7RDoO]I
privateint num = 20; // 每页的记录数 /;J;,G`?
privateList<E> results = null; // 结果 [:Y^0[2
tt OsL')|
/** q9Wtu7/
* 结果总数 |9@;Muq;
*/ JaTW/~ TU
publicint getCount(){ !h;VdCCi#
return count; kSrzIq<xre
} 5
[*jfOz
3J{'|3x
publicvoid setCount(int count){ ;* Jd#O
this.count = count; A#{*A
} /_HL&|N_5
r>OE[C69
/** uhLW/?q.
* 本结果所在的页码,从1开始 q1j[eru
* ""=Vt]
* @return Returns the pageNo. g.qp _O
*/ $1F9TfA
publicint getP(){ \qPrY.-
return p; 1F-L(\oKm
} f&J*(F*u
auU{Iy
/** +-i@R%
* if(p<=0) p=1 ~5zhK:7c
* KA7nncg;,
* @param p }#@LZ)]hK
*/ USY^
[@o[f
publicvoid setP(int p){ Y-9F*8<
if(p <= 0) Spb'jAKj'
p = 1; S45jY=)z
this.p = p; 6kk(FVX
} ~drNlt9jf
{WChD&v
/** W&nVVV8s@
* 每页记录数量 s5 BV8 M
*/ >{[J+f{~|
publicint getNum(){ |gNOv;l
return num; c
s>W6
} GOjri
^[6AOz+L
/** -#@;-2w
* if(num<1) num=1 @,hvXl-G *
*/ !!AutkEg>
publicvoid setNum(int num){ sj1x>
if(num < 1) k 'o?/
num = 1; wS*UXF&f
this.num = num; Mh\c +1MFs
} -Cl0!}P4I
6[i-Tl
/** R~o?X^^O
* 获得总页数 q0o6%c:gW
*/ >dO^pDSs
publicint getPageNum(){ zB4gnVhus|
return(count - 1) / num + 1; v "07H
} _nF_RpS
59|Tmf(dS;
/** X#fI$9a
* 获得本页的开始编号,为 (p-1)*num+1 I#0$5a},u^
*/ gs'(px
publicint getStart(){ 5_PD?lg
return(p - 1) * num + 1; 3j6$!89'
} K-/fq=z
MQ01!Y[q_7
/** ]Kd:ZmJ
* @return Returns the results. R lv|DED$
*/ 3;&N3:,X
publicList<E> getResults(){ <7qM;)g
return results; Ma$b(4dB
} 0@>3fR
F2#^5s(
public void setResults(List<E> results){ ,JR7N_"I
this.results = results; 5 gE
} 6+>q1,<
;Q ]bV52
public String toString(){ [/I4Pe1Yj%
StringBuilder buff = new StringBuilder `5
bHZ
6g)21Mh#
(); E0w>c'kH
buff.append("{"); &BP%~
buff.append("count:").append(count); t>^An:xT
buff.append(",p:").append(p); X\_ku?]v
buff.append(",nump:").append(num); ZT!DTb
B
buff.append(",results:").append dx|j,1e
8{'L:yzMY
(results); ' y1=Z
buff.append("}"); k#U?Xs>
return buff.toString(); ~R3@GaL1
} S?&ntUah
Rb?6N
} tONxV`
?EdF&^[3rD
VCtj8hKDr