Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 ##=$$1Ki
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 bu|.Jw"
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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 X}v*"`@Q
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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 C)z4Cn9#
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分页支持类: [|OII!"
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java代码: Gv&G2^
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package com.javaeye.common.util; t\K
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import java.util.List; /ooGyF
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publicclass PaginationSupport { \;)g<TwL
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publicfinalstaticint PAGESIZE = 30; %hsCB
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privateint pageSize = PAGESIZE; e~SK*vR%]
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privateList items; qT@h/Y
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privateint totalCount; aDKb78 1d
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privateint[] indexes = newint[0]; cjEqN8
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privateint startIndex = 0; TU0-L35P1
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public PaginationSupport(List items, int v.Ba
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totalCount){ {R!yw`#^B
setPageSize(PAGESIZE); ZwS:Te9-
setTotalCount(totalCount); ma~#E$i&
setItems(items); \b"rf697,
setStartIndex(0); E$)| Kv^
} WR)=VE
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public PaginationSupport(List items, int Plp.\N%f3
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totalCount, int startIndex){ l(?B0
setPageSize(PAGESIZE); _]`7et\=
setTotalCount(totalCount); [s>3xWZ+a
setItems(items); fY!?rZ)$
setStartIndex(startIndex); X_TjJmc
} 0SIC=p=J
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public PaginationSupport(List items, int dH^6K0J
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totalCount, int pageSize, int startIndex){ ST*h{:u&A
setPageSize(pageSize); K3?5bT_{
setTotalCount(totalCount); Y<xqws
setItems(items); S/'0czDMW
setStartIndex(startIndex); a;HAuy`M x
} E5&Z={
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publicList getItems(){ I}4
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return items; *): |WDR
} Cs6`lX >
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publicvoid setItems(List items){ j>\c >U
this.items = items; r<UVO$N
} AHb_B gOU*
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publicint getPageSize(){ i.Rl&t
return pageSize; $+*nb4
} |Kd#pYt%O
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publicvoid setPageSize(int pageSize){ Sa= tiOv
this.pageSize = pageSize; +~^S'6yB
} n[3z_QI
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publicint getTotalCount(){ 0\dmp'j]
return totalCount; .EKlw##
} m-AF&( ;K
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publicvoid setTotalCount(int totalCount){ "I.6/9
if(totalCount > 0){ h6h6B.\Ld
this.totalCount = totalCount; Ei4^__g\'
int count = totalCount / <7^|@L
6
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pageSize; u&:N`f
if(totalCount % pageSize > 0) =l`)b
count++; NI V}hf YF
indexes = newint[count]; #fuUAbU0X
for(int i = 0; i < count; i++){ v"G1vSx)BT
indexes = pageSize * o<Zlm)"%1
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} U]3!"+Y1P
}else{ hd)Jq'MCS
this.totalCount = 0; L/8oqO|
} *()['c#CC
} <0CjEsAB]
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publicint[] getIndexes(){ KL&/Yt
return indexes; 2*NPK}
} v)5;~.+%
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publicvoid setIndexes(int[] indexes){ LDlYLsF9
this.indexes = indexes; ZJ/528Ju
} J>Ar(p
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publicint getStartIndex(){ A,~3oQV
return startIndex; B7%,D}
} ,!:c6F+
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publicvoid setStartIndex(int startIndex){ $BwWQ?lp
if(totalCount <= 0) hi8q?4jE
this.startIndex = 0; f8Hq&_Pn
elseif(startIndex >= totalCount) ~apt,hl
this.startIndex = indexes b'z
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[indexes.length - 1]; *rq*li;
elseif(startIndex < 0) o*KAS@&
this.startIndex = 0; !M~:#k
else{ CD`a-]6qA
this.startIndex = indexes HMq}){=S
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[startIndex / pageSize]; zj`c%9N+
} ^#_gk uyd!
} N^;lp<{6?
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publicint getNextIndex(){ ^z
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int nextIndex = getStartIndex() + uKJ:)oyaCP
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pageSize; q<09]i
if(nextIndex >= totalCount) SyL"Bmi
return getStartIndex(); DGTLlBkT
else #
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return nextIndex; c9|4[_&B~
} *l_a=[<[
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publicint getPreviousIndex(){ ZdW+=;/#
int previousIndex = getStartIndex() - /$; Z ~^P
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pageSize; yhH2b:nY(9
if(previousIndex < 0) qYoW8e
return0; c~T{;
else Pp?P9s{
return previousIndex; Q7+WV`&
} 9wL2NC31Q
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} ,+i^]yF3j
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抽象业务类 uz3cho'
java代码: Y9abRrK
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/** X_PzK'#m
* Created on 2005-7-12
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*/ K'&,]r#
package com.javaeye.common.business; ?O25k!7
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import java.io.Serializable; ]yOM
import java.util.List; m-{DhJV
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import org.hibernate.Criteria; kH 9k<{
import org.hibernate.HibernateException; }wf8y
import org.hibernate.Session; sX?arI=_U
import org.hibernate.criterion.DetachedCriteria; ~D5
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import org.hibernate.criterion.Projections; '&CZ%&(Gw
import 0hS&4nW
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org.springframework.orm.hibernate3.HibernateCallback; k7Nx#%xx
import oypLE=H
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org.springframework.orm.hibernate3.support.HibernateDaoS 2[w9#6ly
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upport; <(E)M@2
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import com.javaeye.common.util.PaginationSupport; i?_Q@uA~<:
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public abstract class AbstractManager extends 6Emn@Mn=
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HibernateDaoSupport { rT="ciQ
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privateboolean cacheQueries = false; u&y> '
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privateString queryCacheRegion; Qz`evvH
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publicvoid setCacheQueries(boolean -t_&H\_T
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cacheQueries){ ^(Gl$GC$Mu
this.cacheQueries = cacheQueries; -Ua5anzB
} WDNj7
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publicvoid setQueryCacheRegion(String r%: :q^b3
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queryCacheRegion){ T:j41`g%s
this.queryCacheRegion = i(A`'V8GY
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queryCacheRegion; [?z;'O}y
} ['(qeS@5O
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publicvoid save(finalObject entity){ eI|FrBq%
getHibernateTemplate().save(entity); z{.&sr>+v
} NiG&Lw*8
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publicvoid persist(finalObject entity){ ?r;F'%N=
getHibernateTemplate().save(entity); K*~xy bA
} 8\il~IFyi
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publicvoid update(finalObject entity){ SP0ueAa}
getHibernateTemplate().update(entity); DI{Qs[
} #~Kno@
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publicvoid delete(finalObject entity){ !le#7Kii
getHibernateTemplate().delete(entity); El}~3|a?
} )~)T[S
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publicObject load(finalClass entity, :|l0x a
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finalSerializable id){ BDN}`F[F
return getHibernateTemplate().load JA >&$h
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(entity, id); BDp(&=ktq
} axG%@5
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publicObject get(finalClass entity, B <Jxj
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finalSerializable id){ __z/X"H
return getHibernateTemplate().get }2=~7&)
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(entity, id); +o.#']}Pl
} &~"N/o
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publicList findAll(finalClass entity){ iR4"I7J
return getHibernateTemplate().find("from o/U}G,|G
='#7yVVcs
" + entity.getName()); ?zo7.R-Vac
} }m!T~XR</
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publicList findByNamedQuery(finalString (>Sy,
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namedQuery){ JpQV7}$
return getHibernateTemplate lfoPFJ
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().findByNamedQuery(namedQuery); Mt4`~`6
} wC1)\ld
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publicList findByNamedQuery(finalString query, @
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finalObject parameter){ kaZcYuT.9
return getHibernateTemplate yrzyus
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().findByNamedQuery(query, parameter); =+e;BYD#!
} 9dg+@FS}=
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publicList findByNamedQuery(finalString query, p=Qo92
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finalObject[] parameters){ ZB}zT9JaE
return getHibernateTemplate (Q"s;g
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().findByNamedQuery(query, parameters); 7n#Mh-vq
} kDKfJp&a
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publicList find(finalString query){ Si;eBPFH
return getHibernateTemplate().find kKQD$g.z6
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(query); )q7!CG'oY
} N8wA">u
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publicList find(finalString query, finalObject K`R
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parameter){ Yu%ZwTvw
return getHibernateTemplate().find M/6q
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(query, parameter); *fDhNmQ `
} L{1PCs36c
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public PaginationSupport findPageByCriteria g dBH\K (\
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(final DetachedCriteria detachedCriteria){ ][Cg8
return findPageByCriteria Cp-p7g0wlg
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); {NIE:MXX
} ~<_PjV
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public PaginationSupport findPageByCriteria ~EhM"go
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(final DetachedCriteria detachedCriteria, finalint !uHVg(}
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startIndex){ sr$JFMTO11
return findPageByCriteria !_1RQ5]^
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(detachedCriteria, PaginationSupport.PAGESIZE, w#$Q?u ,G
=
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startIndex); 6c#1Do(W+
} SQBe}FlktK
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public PaginationSupport findPageByCriteria X04JQLhy"
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(final DetachedCriteria detachedCriteria, finalint yFqB2(Dv
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pageSize, ,
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finalint startIndex){ "M:0lUy
return(PaginationSupport) jTz~
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getHibernateTemplate().execute(new HibernateCallback(){ .{#J2}+[_}
publicObject doInHibernate 20RI S j
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(Session session)throws HibernateException { #ruL+-8!<
Criteria criteria = +,ZQ(
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detachedCriteria.getExecutableCriteria(session); )1!*N)$
int totalCount = 1O;q|p'9
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((Integer) criteria.setProjection(Projections.rowCount g)~"-uQQ
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()).uniqueResult()).intValue(); #ANbhHG
criteria.setProjection ~Wj.
4b*
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(null); -Fs<{^E3j
List items = 9rhl2E
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criteria.setFirstResult(startIndex).setMaxResults h}jE=T5Hc
.q(1
(pageSize).list(); D~JrO]mi
PaginationSupport ps = <@2g.+9
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new PaginationSupport(items, totalCount, pageSize, ?r-W
, n
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startIndex); sM'%apM#
return ps; PPSSar
} A^"( VaK
}, true); jAb R[QR1%
} S6Fn(%T+9
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public List findAllByCriteria(final <2{-ey]
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DetachedCriteria detachedCriteria){ S U$U
return(List) getHibernateTemplate nhP ua&
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().execute(new HibernateCallback(){ =L&}&pT
publicObject doInHibernate CQm(N
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(Session session)throws HibernateException { w0L+Sj db
Criteria criteria = f^?k?_~PN
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detachedCriteria.getExecutableCriteria(session); aaM76;
return criteria.list(); f&
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} f+Ht
}, true); E;AOCbV*$
} JQ)w/@Vu=
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public int getCountByCriteria(final 0'0GAh2
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DetachedCriteria detachedCriteria){ f/NfvLi(AU
Integer count = (Integer) m3E`kW|
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getHibernateTemplate().execute(new HibernateCallback(){ YE5B^sQ1
publicObject doInHibernate qt!0#z8
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(Session session)throws HibernateException { G :JQ_w
Criteria criteria = Dq G m
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detachedCriteria.getExecutableCriteria(session); %qqX-SF0C
return .~t.B!rVSB
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criteria.setProjection(Projections.rowCount ,4tuWO)"
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()).uniqueResult(); 0<C]9[l
} V 0M&D,
}, true); V*1hoC#
return count.intValue(); aBonq]W
} .>Fy ]Cqoh
} )UgLs|G~
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用户在web层构造查询条件detachedCriteria,和可选的 R
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 Q'qz(G0
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PaginationSupport的实例ps。 6A9
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ps.getItems()得到已分页好的结果集 +XP9=U*g
ps.getIndexes()得到分页索引的数组 2j
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ps.getTotalCount()得到总结果数 n3Q Rn^
ps.getStartIndex()当前分页索引 LW '3m5
ps.getNextIndex()下一页索引 1ms(03dp
ps.getPreviousIndex()上一页索引 VW/ICX~"d
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 kt;uB
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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 F2:nL`]b[
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一下代码重构了。 JRYCM}C]
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我把原本我的做法也提供出来供大家讨论吧: *H({q`j33k
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首先,为了实现分页查询,我封装了一个Page类: v%$c_'d
java代码: n/Fx2QC{
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/*Created on 2005-4-14*/ '`nf7b(
package org.flyware.util.page; x^]J^L45
vnS;T+NZSC
/** sRkPXzK
* @author Joa x=%wPVJ
* tEFbL~n
*/ b[s=FH]#N
publicclass Page { L }L"BY3$
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/** imply if the page has previous page */ RR9G$}WS(
privateboolean hasPrePage; ;\48Q;
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/** imply if the page has next page */ J[ 7Sf^r
privateboolean hasNextPage; p38RgEf
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/** the number of every page */ E,p4R%:$@1
privateint everyPage; PyQ
P K,
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/** the total page number */ 0n-S%e5
privateint totalPage; =Hf`yH\#
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/** the number of current page */ Lh
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privateint currentPage; rMEM$1vPU
@b{I0+li"/
/** the begin index of the records by the current uP NZ^lM
# ;3v4P
query */ ki=]#]rg
privateint beginIndex; *1`q
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f)#rBAkt
/** The default constructor */ w)7 s]Ld
public Page(){ 9[,+4&wX7
|$+
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} 1}ER+;If
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/** construct the page by everyPage 4RyQ^vL
* @param everyPage =s/UF _JN
* */ '<-F3
public Page(int everyPage){ uG,*m'x']
this.everyPage = everyPage; |kK_B
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} >& `;@ZOH
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/** The whole constructor */ U#>K(
public Page(boolean hasPrePage, boolean hasNextPage, 'Hv=\p4$1
teX)!N [
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int everyPage, int totalPage, O0RV>Ml'&
int currentPage, int beginIndex){ .{,fb
this.hasPrePage = hasPrePage; ,0\Pr
this.hasNextPage = hasNextPage; d8ck].m=
this.everyPage = everyPage; ni~1)"U.
this.totalPage = totalPage; %2,'x
this.currentPage = currentPage; NnTAKd8
this.beginIndex = beginIndex; 88g|(k/
} < VrHWJo
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/** &3CC |
* @return 6BH
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* Returns the beginIndex. @5tGI U;1
*/ %Fp1c K
publicint getBeginIndex(){ , .]1N:
return beginIndex; J7FzOwd1h
} #M@Ki1
|* v w(
/** @ebSM#F?
* @param beginIndex uq\[^
* The beginIndex to set. Mem1X rBH
*/ e]zd6{g[m
publicvoid setBeginIndex(int beginIndex){ ~ya@ YP]';
this.beginIndex = beginIndex; EK2mJCC|
} Aq;WQyZ2
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/** R
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* @return ,-`A6ehg
* Returns the currentPage. ^^(!>n6r^
*/ d*R('0z{
publicint getCurrentPage(){ @XQItc<
return currentPage; L['g')g.
} * _@t$W
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/** 1+v!)Y>Z&
* @param currentPage H$rNT/C
* The currentPage to set. lN~u='Kc
*/ z$Z{ LR
publicvoid setCurrentPage(int currentPage){ \'.|7{Xu
this.currentPage = currentPage; s6(bTO.
} 'mYUAVmSC#
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/** ;!pSYcT,
* @return 4_W*LG~2s
* Returns the everyPage. {66P-4Ev(
*/ OJT%?P%@{
publicint getEveryPage(){ }NY! z^
return everyPage; :rSCoi>K
} ~%!"!Z4
75W@B}dZd
/** WwF2Ry^a
* @param everyPage cI (}
* The everyPage to set. Wxa</n8S[n
*/ Nq"J[l*+g
publicvoid setEveryPage(int everyPage){ 8iUYZF
this.everyPage = everyPage; ,w%hD*
} t~M0_TnXlP
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/** ukc<yc].+?
* @return Jxsch\
* Returns the hasNextPage. |Ng}ZLBM
*/ 89P'WFOFK
publicboolean getHasNextPage(){ E~
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return hasNextPage; b^R_8x
} =4#p|OZP
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/** 8;$zD]{D1
* @param hasNextPage B\\M%!a>
* The hasNextPage to set. O&evv8 6L
*/ {4>N2mP{M
publicvoid setHasNextPage(boolean hasNextPage){ COH9E\ZGF
this.hasNextPage = hasNextPage; o?/fObV@(
} cCv@fks
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/** v,Uu)Z
* @return UTVqoCHA
* Returns the hasPrePage. UO4z~
*/ Xq%ijo
publicboolean getHasPrePage(){ k{J\)z
return hasPrePage; ^\g?uH6k U
} |* B9{/;4
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/** }ws(:I^
* @param hasPrePage @y8)
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* The hasPrePage to set. q$kx/6=k
*/ _18Aek
publicvoid setHasPrePage(boolean hasPrePage){ A7R [~
this.hasPrePage = hasPrePage; ,SH^L|I
} p9[gG\
!@[@&.
/** e'2w-^7
* @return Returns the totalPage. _Lgi5B%
* ( "wmc"qH
*/ e4<St`K
publicint getTotalPage(){ +2,EK
return totalPage; t#2szr+
} \kP1 Jr
G;AJBs>Y}
/** 7`HKa@
* @param totalPage o?5;l`.L}
* The totalPage to set. g9AA)Ykp
*/ B4{F)Zb
publicvoid setTotalPage(int totalPage){ 9`cj9zz7
this.totalPage = totalPage;
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} 6ag0c&k
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} 9#1Jie$
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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 %afz{a5
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个PageUtil,负责对Page对象进行构造: 8TCbEPS@Q
java代码: ZM_-g4[H
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/*Created on 2005-4-14*/ =\gK<Xh
package org.flyware.util.page; d RHw]!.
mw*KLMo42
import org.apache.commons.logging.Log; ?i$MinK
import org.apache.commons.logging.LogFactory; @=qWwt4~
q OV$4[r
/** VLC=>w\,
* @author Joa 22R
,
* >'v{o{k|C
*/ "@L|Z6U(
publicclass PageUtil { T1c&3
B~`:?f9ny5
privatestaticfinal Log logger = LogFactory.getLog b&!x.+d-z
9>ML;$T&
(PageUtil.class); P.3kcZ
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/** B3Ws)nF"
* Use the origin page to create a new page 6 -IThC
* @param page H={5>;8G
* @param totalRecords 0}-MWbG
* @return RY]jY | E
*/ dC?l%,W
publicstatic Page createPage(Page page, int 9PG3cCr?
(t"e#b(:
totalRecords){ f<vZ4 IU
return createPage(page.getEveryPage(), :8Ugz ~i
m0 ]Lc{
page.getCurrentPage(), totalRecords); 1 Ay.^f
} KNSMx<GP
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/** B:fulgh2ni
* the basic page utils not including exception K}QZdN']
K QCF "
handler =~'y' K]
* @param everyPage A>rN.XW
* @param currentPage 3-_`x9u*
* @param totalRecords ,@aF#
* @return page ad`7[fI
*/ =z#j9'n$@
publicstatic Page createPage(int everyPage, int g3c,x kaO
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currentPage, int totalRecords){ +GT"n$)+
everyPage = getEveryPage(everyPage); ?S'Wd=
currentPage = getCurrentPage(currentPage); .x_F4 #Ka
int beginIndex = getBeginIndex(everyPage, ?-=<7
~$
%)=c#H1
currentPage); >+Y@rj2
int totalPage = getTotalPage(everyPage, ms#|Yl1/|
r^`~GG!,Q
totalRecords); Z8o8>C\d9/
boolean hasNextPage = hasNextPage(currentPage, 8i^d*:R
.s>.O6(^%
totalPage); Ex5LhRe>=
boolean hasPrePage = hasPrePage(currentPage); m5lTf
,R=)^Gh{
returnnew Page(hasPrePage, hasNextPage, 5)i+x-
everyPage, totalPage, qTV.DCP
currentPage, QoS]QY'bZ
zRgl`zREr
beginIndex); tw&biLM5T
} aA-s{af
LuWY}ste
privatestaticint getEveryPage(int everyPage){ t{O2JF#5u
return everyPage == 0 ? 10 : everyPage; J"Nn.iVq
} <,Fj}T-
!gj_9"<
privatestaticint getCurrentPage(int currentPage){ $`_xP1bUT
return currentPage == 0 ? 1 : currentPage; #{zF~/Qq
} T26'b .
GhW{6.^
privatestaticint getBeginIndex(int everyPage, int K&up1nZ@(
h%! ,|[|
currentPage){ ~/;shs<9EM
return(currentPage - 1) * everyPage; V(F1i%9l g
} YRU#/TP
_s+_M+@et
privatestaticint getTotalPage(int everyPage, int
cfL:#IM
Y"E*#1/
totalRecords){ ,ZvlKN
int totalPage = 0; _nec6=S6(
.> ^U
mM
if(totalRecords % everyPage == 0) 9Qn*frdY,
totalPage = totalRecords / everyPage; vzZ"TSP
else 6 IKi*}
totalPage = totalRecords / everyPage + 1 ; I~25}(IDZ"
]_2<uK}fg
return totalPage; r-5xo.J'
} _Q}vPSJviC
sLW e \o
privatestaticboolean hasPrePage(int currentPage){ \/?&W[T F
return currentPage == 1 ? false : true; p&ZLd`[
} S=X_7V
yOyuMZo6
privatestaticboolean hasNextPage(int currentPage, Y|aaZ|+
|],ocAN{
int totalPage){ jiP^Hz"e
return currentPage == totalPage || totalPage == eI+p
HQ^:5XH
0 ? false : true; o_PQ]1
} D>K=D"
qIk(ei
iH)-8Q
} / a$B8,
qoOq47F
Y{
w9D`}
XVYj
X
@O)1Hnm
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。 8v\^,'@
/qweozW_+
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 ^'$P[
|/;X-+f8
做法如下: "PC9[i
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 y@\J7 h:
2UEjn>2
的信息,和一个结果集List: VP:9&?>G
java代码: [\.@,Y0j
7z3YzQ=Kg
G/&Wc2k
/*Created on 2005-6-13*/ 6Wc.iomx8
package com.adt.bo; 90!67Ap`x
-{eI6#z|\A
import java.util.List; lNB<_SO
.<.#g+
import org.flyware.util.page.Page; N683!wNX
`yrJ }f
/** <[tU.nh
* @author Joa S3?U-R^`
*/ AP(%m';
publicclass Result { I=&Kn@^
9l}G{u9a
private Page page; nrCr9#
2w>yW]
private List content; F^X:5g~K
Z1oUAzpj4
/** L*1yK*
* The default constructor =Y-mc#{8
*/ ]gDX~]f[
public Result(){ O8 5) ^
super(); Y$ '6p."=
} o7v,:e:
B-[qS;PY%
/** P30|TU+B
* The constructor using fields Vnnl~|Xx
* O
718s\#
* @param page w>6cc#>q
* @param content =X=m_\=~@
*/ e%JH q
public Result(Page page, List content){ [,ZHn$\
this.page = page; 5VGr<i&A
this.content = content; `_>44!M
} ^"EK:|Y4%K
yn.f?[G2
/** <{1=4PA
* @return Returns the content. Pe?b#
G
*/ X&cm)o%5Fe
publicList getContent(){ g)^g_4
return content; M]A!jWtE
} YCo qe,5
t? [8k&Z
/** Y]H,rO
* @return Returns the page. H]VoXJ\*
*/ 0Y9fK? (
public Page getPage(){ nBGcf(BE.$
return page; R9O1#s^
} Un\
T}
c
^_JByBD
/** Ep1p>s^
* @param content GJn ~x
* The content to set. ?TY/'-M5
*/ ;BYv&(#u1q
public void setContent(List content){ o/mGd~
this.content = content; #iP5@:!Wm~
} KU (g Zy
5DnX8t+d
/** poVtg}n
* @param page ljJR7<
* The page to set. JId|LHf*P
*/ ]rc=oP;
publicvoid setPage(Page page){ '+E\-X
this.page = page; 4'`y5E
} [K"&1h<>
} 8d8GYTl b)
s?_H<u
Z,5B(X j
Jn)DZv8?
6G]hsgro
2. 编写业务逻辑接口,并实现它(UserManager, c^`(5}39v
w4j,t
UserManagerImpl) `E-cf 7%
java代码: R6-Z]Hu
_/cL"Wf
\Ea(f**2B
/*Created on 2005-7-15*/ T/TMi&:?.
package com.adt.service; _A,mY6*
}g_\?z3gt
import net.sf.hibernate.HibernateException; i=X
B0-
::2(pgH
import org.flyware.util.page.Page; \wxLt}T-Q
-9^A,vX
import com.adt.bo.Result; @]X5g8h
$gysy!2}.
/** ]%Z7wF</
* @author Joa pX]"^f1?O
*/ (5Sv$Xt
publicinterface UserManager { \#q|.d$u
CC.ri3+.
public Result listUser(Page page)throws j2Uu8.8d
AIw< 5lW
HibernateException; >^zbDU1wT
d^ZrI\AJ
} w}r~Wk^dLI
K#4Toc#=V
IhPX/P
0:qR,NW^#
xoyH5ZK@
java代码: *{s
3.=P.
zE1=*zO`
q1vsvL9Q
/*Created on 2005-7-15*/ >!%F$$
package com.adt.service.impl; 2~RG\JWTA
#Iwxt3K
import java.util.List; #Hi$squJ
Bf{c4YiF
import net.sf.hibernate.HibernateException; QV9z81[
&@/25Y2
import org.flyware.util.page.Page; Or,W2
import org.flyware.util.page.PageUtil; >j_N6B!
52#Ac;Y
import com.adt.bo.Result; L}\~)
import com.adt.dao.UserDAO; jC_m0Iwc
import com.adt.exception.ObjectNotFoundException; I"bz6t\~|
import com.adt.service.UserManager; ^{l$>e]
3jDAj!_ea
/** y]b&3&
* @author Joa !nt[J$.z^
*/ 40Hm+Ge
publicclass UserManagerImpl implements UserManager { i4H,Ggb
V3q[ #.o
private UserDAO userDAO; feG#*m2g
C] >?YR4
/** j-9Zzgr
* @param userDAO The userDAO to set. a/dq+
*/ se&Q\!&M
publicvoid setUserDAO(UserDAO userDAO){ OO*2>Qy~z
this.userDAO = userDAO; p~f=0K
} ^F:Bj&0v[
`$i/f(t6`
/* (non-Javadoc) XWv;l)
* @see com.adt.service.UserManager#listUser #MAXH7[
+S
],){
(org.flyware.util.page.Page) >m#bj^F\
*/ Qkb=KS%z
public Result listUser(Page page)throws 55Ag<\7
}b=Cv?Zg$m
HibernateException, ObjectNotFoundException { eH^~r{{R
int totalRecords = userDAO.getUserCount(); *m*sg64Zw
if(totalRecords == 0) +wxDK A_
throw new ObjectNotFoundException =gQ^,x0R9
olca
Z
("userNotExist"); !"<~n-$B
page = PageUtil.createPage(page, totalRecords); E8"$vl&c]
List users = userDAO.getUserByPage(page); 5dkXDta[G
returnnew Result(page, users); XN}^:j_2
} P9jPdls
?3a:ntX h
} |VQmB/a
SkyX\&
hD9b2KZv
]'5 G/H5?;
'ZAl7k .
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 ,v_NrX=f?
-T{G8@V0I
询,接下来编写UserDAO的代码: "WZ |
3. UserDAO 和 UserDAOImpl: Hp5.jor(k
java代码: 3oBR
@^Yr=d ba
a9y+FCA
/*Created on 2005-7-15*/ t$g@+1p4
package com.adt.dao; ubUVxYD?
]8CgHT[^7
import java.util.List; qrufnu5cC
HMmB90P`
import org.flyware.util.page.Page; iB#*XJ;q
lb\VQZp!y
import net.sf.hibernate.HibernateException; 4Be\5Byr
do:IkjU~
/** ?}"39n
* @author Joa 'wni.E&
*/ h&2l0|8k
publicinterface UserDAO extends BaseDAO { fi [4F
%jn)=;\
publicList getUserByName(String name)throws u7lO2C7
k8 z1AP
HibernateException; $rm/{i_7
D|$Fw5!^k6
publicint getUserCount()throws HibernateException; y_r(06"z1
(!%9#
publicList getUserByPage(Page page)throws M< /
tn}MKo
HibernateException; .zv BV_I
8p_6RvG
} q5{h@}|M
+
f,Kt9Cy
kxmc2RH>nB
n+ S&[Y
`#"xgOSP>
java代码: v?0F
xSq{pxX
Z): Nd9
/*Created on 2005-7-15*/ }CL7h;5N 3
package com.adt.dao.impl; g
cb6*@u!
qKTzigjj
import java.util.List; F}?4h Dt
'}$$0S.DC
import org.flyware.util.page.Page; 8p]9A,Uq&
\3`r/,wY
import net.sf.hibernate.HibernateException; 33g$mUB
import net.sf.hibernate.Query; VS@e[,
%~L"TK`?
import com.adt.dao.UserDAO; ~z)JO'Z$
?[7KN8$
/** 1>Q4&1Vn
* @author Joa Ll.P>LH
*/ J";4+wA7
public class UserDAOImpl extends BaseDAOHibernateImpl e,
fZ>EJ
sLUOs]cj
implements UserDAO { +t3o5&
~*x 2IPiH
/* (non-Javadoc) 1!NrndJ I
* @see com.adt.dao.UserDAO#getUserByName */2nh%>$
~G 3txd
(java.lang.String) 9BAvE\o0
*/ 8N \<o7t%
publicList getUserByName(String name)throws KwU;+=_.
SEVB.;
HibernateException { ~LQzt@G4
String querySentence = "FROM user in class +lxjuEiae
R3%%;` c=
com.adt.po.User WHERE user.name=:name"; *wx95?H0Z
Query query = getSession().createQuery ERia5HnoD,
Zz"8
(querySentence); EjMVlZC>
query.setParameter("name", name); m`}mbm^
return query.list(); 4AMe>s
} U~USwUzgY
3&mpn,
/* (non-Javadoc) Ft38)T"2R\
* @see com.adt.dao.UserDAO#getUserCount() Lv#0-+]$Bt
*/ mm;sf
publicint getUserCount()throws HibernateException { w!'y,yb%
int count = 0; %%NT m
String querySentence = "SELECT count(*) FROM xkv%4H>
> l]Ble
user in class com.adt.po.User"; Ft?eqDS1
Query query = getSession().createQuery V>/,&~0
vn!5@""T
(querySentence); hQ'W7EF
count = ((Integer)query.iterate().next YmOj.Q&
ea]qX6)UZ
()).intValue(); %z=:P{0UQ
return count; ka6E s~
} *jvP4Nz)k
|1zfXG,R
/* (non-Javadoc) FPH2dN
* @see com.adt.dao.UserDAO#getUserByPage p]ujip
(;&}\OX6nm
(org.flyware.util.page.Page) KIp^|
k7>
*/ '~
H`Ffd.
publicList getUserByPage(Page page)throws 3dlY_z=0
NGJst_
HibernateException { (T%?@'\
String querySentence = "FROM user in class eL~3CAV{
)[oP`Z
com.adt.po.User"; b.v +5=)B
Query query = getSession().createQuery tDRo)z
d%. |MAE
(querySentence); E- [Eg
query.setFirstResult(page.getBeginIndex()) V:>r6
.setMaxResults(page.getEveryPage()); 0N~kq-6.\
return query.list(); ?|98Y"w
} (~o"*1fk>
M[~{!0Uz
g
} 7e\Jg/FU
|'z24 :8
{@F'BB\
D'vaK89\
7B=VH r
至此,一个完整的分页程序完成。前台的只需要调用 zjh:jrv~
6 &0r/r
userManager.listUser(page)即可得到一个Page对象和结果集对象 v?
OUd^
%S%IW
的综合体,而传入的参数page对象则可以由前台传入,如果用 Hi$R"O
(
@6|<c
webwork,甚至可以直接在配置文件中指定。 (xHu@l!]
i1XRBC9
下面给出一个webwork调用示例: l5.k2{'
java代码: ^lt2,x
ZE-vroh
x"g)pGsT
/*Created on 2005-6-17*/ S3l^h4
package com.adt.action.user; wU>Fz*
/,\U*'-
import java.util.List; QS!Z*vG
!#:5^":;
import org.apache.commons.logging.Log; e5 L_<V^Jo
import org.apache.commons.logging.LogFactory; WG3!M/4r H
import org.flyware.util.page.Page; \pfa\,rW
w;yzgj:n&f
import com.adt.bo.Result; R~T}
import com.adt.service.UserService; _dRB=bl"O
import com.opensymphony.xwork.Action; VnVBA-#r|
^3BPOK[*gB
/** i%[ gNh
* @author Joa *asv^aFpS
*/ iiQ
q112`
publicclass ListUser implementsAction{ ?&;_>0P
=PciLh
privatestaticfinal Log logger = LogFactory.getLog LXh}U>a9
icIn>i<m
(ListUser.class); n@xQ-v
nq HpYb6I0
private UserService userService; {0w2K82
!u@P\8M}
private Page page; |T$?vIG[
g(9* !g
privateList users; NIVR;gm
Ht4O5yl"
/* Yj1|]i5b
* (non-Javadoc) '(FC
* IycZ\^5 *-
* @see com.opensymphony.xwork.Action#execute() [#mkTY
*/ N|$9v{ j_
publicString execute()throwsException{ |(Mxbprz
Result result = userService.listUser(page); {'tfU
page = result.getPage(); $BMXjXd}
users = result.getContent(); :MY=Q]l
return SUCCESS; :>JfBJ]|
} E`I(x&_
n)"JMzjQ<
/** -f&vH_eK
* @return Returns the page. !5(DU~S*@S
*/ l[c '%M |N
public Page getPage(){ 0t%]z!
return page; e}1Q+h\
} w(&EZDe
\.}T_,I
/** wR@>U.XT@
* @return Returns the users. )f|`mM4DW!
*/ +1YEOOfVY
publicList getUsers(){ ioD8-
return users; 9Z!n!o7D
} ;W|NG3_y
XDJE]2^52?
/** 6T'UWh0S
* @param page H" `'d
* The page to set. 'k[qx}
*/ TLVsTM8P
publicvoid setPage(Page page){ t&?{+?p:
9
this.page = page; /]3[|
} q+\<%$:u
2I [zV7 @t
/** `
= O
* @param users wQUl!s7M;
* The users to set. &&9|;0<
*/ NOQ^HEi
publicvoid setUsers(List users){ ,M.}Q ak^
this.users = users; o& FOp'
} rL1yq|]I
HvG %##
/** u_$4xNmQ
* @param userService dEtjcId
* The userService to set. 2$5">%?
*/ +FqD.= 8
publicvoid setUserService(UserService userService){ >-I <`y-H
this.userService = userService; 4T(d9y
} O*l,&5
} }x`Cnn
@@H_3!B%4v
B4RrUA32
P M [_0b
?h&XIM(
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, 5<dg@,\
MSQ^ovph
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 ]nUr E6
/RJ
么只需要: ~^' ,4<K-}
java代码: F]yB=
YUEyGhkMV{
6/S.sj~
<?xml version="1.0"?> y|ZL<L
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork N9_* {HOy
NSz}
1.0//EN" "http://www.opensymphony.com/xwork/xwork- oL@ -<;zKO
T<pG$4_
1.0.dtd"> w-pgtO|Us
ce\d35x!
<xwork> RH;ulAD6(~
\s&Mz;:
<package name="user" extends="webwork- -p_5T*R
A+RW=|:
interceptors"> UmWXv#q\l
/%& d:
<!-- The default interceptor stack name dR]-R/1|
kP%hgZ
--> UA8hYWRP
<default-interceptor-ref losqc *|
[
@eA o>
name="myDefaultWebStack"/> P 0.cF]<m
eZPeyYX
<action name="listUser" HJAiQ[m5s
0qJ (RB
class="com.adt.action.user.ListUser"> :>fT=$i@
<param OKMdyyO<l
sr6BC.
name="page.everyPage">10</param> {h+8^
<result Y.Zd_,qy
|&= -Nm
name="success">/user/user_list.jsp</result> 2nkA%^tR
</action> =8T!ldVxES
6]?%1HSi
</package> ~-zTY&c_
le'RU1k
</xwork> NbU`_^oC
=o##z5j
K
jjV'`Vy)
\s*M5oN]]
d. vNiq,`
e3;&
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 %v8&
v@Uk% O/
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。 }pMVl
VC88re`
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 .kBkYK8*t
<t"T'\3
q~R8<G%YK
OS,!`8cw
vdq=F|&
我写的一个用于分页的类,用了泛型了,hoho \l:R]:w;ZI
<==uK>pET
java代码: :'DyZy2Fd
l/G+Xj4M
dxs5woP
package com.intokr.util; %VO+\L8Fs
ZW [&7[4
import java.util.List; &THtQ1D
+06{5-,
/** @A1f#Ed<
* 用于分页的类<br> $t;:"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> 7~XC_Yc1
* Z`tmuu
* @version 0.01 1jg* DQ7L
* @author cheng 4,sE{%vb
*/ cz9J&Le>
public class Paginator<E> { 0~ho/ _
privateint count = 0; // 总记录数 zzf@U&x<
privateint p = 1; // 页编号 E#KZZ lbx
privateint num = 20; // 每页的记录数 f]/2uUsg%
privateList<E> results = null; // 结果 {1SsHir>
dS6 $
/** >.Gmu
* 结果总数 uBRlvNJ
*/ _c>ww<*3
publicint getCount(){ B r#{
return count; k77IXT_7u
} OvX&5Q5
{nKw<F2
publicvoid setCount(int count){ :|W=2(>
this.count = count; 2#.s{ Bv
} %P0
0&,D&y%
/** hQ@k|3=Re
* 本结果所在的页码,从1开始 t.9s4 9P
* (.:*GUg
* @return Returns the pageNo. D0\>E}Y E
*/ <,)R`90_X6
publicint getP(){ ,&UKsrs_
return p; a dqS.xs
} ,->K)Rs ;
So&gDR;b
/** /"Vd( K2Z
* if(p<=0) p=1 f5V-;
* v])ew|
* @param p OE@[a
*/ Q7aPW\-
publicvoid setP(int p){ Jo {:]:
if(p <= 0) r'*$'QY-N
p = 1; w7@`:W
this.p = p; N#ggT9>X
} B.; qvuM~
H'k}/<%Q
/** \n[kzi7
* 每页记录数量 VCWW(Y1Fd
*/ >aAM&4
publicint getNum(){ eNd&47lJ
return num; ov_l)vt
} +aOdaNcI
%LrOGr
/** L?h?LZnq
* if(num<1) num=1 vIRT$W' O}
*/ fxd+0R;f
publicvoid setNum(int num){ '[WL8,.Q
if(num < 1) 9f!
M1
num = 1; vxmX5.
this.num = num; -0^]:
} g=t`3X#d
v'i'I/
/** KZ%i&w#<
* 获得总页数 |]9@JdmV
*/ T01Iu
publicint getPageNum(){ OIPY,cj~
return(count - 1) / num + 1; u!K1K3T6k
} FoetP`
xF[%R{Mn'
/** 8s)b[Z5
* 获得本页的开始编号,为 (p-1)*num+1 ]CzK{-W
*/ u#Ig!7iUu
publicint getStart(){ zr|DC] 3
return(p - 1) * num + 1; PLkS-B
} i47LX;}
JdS,s5Z>
/** R;!,(l
* @return Returns the results. D./{f8
*/ GeP={lj
publicList<E> getResults(){ O^cC+@l!4
return results; qnp}#BZ
} 7FE36Ub9
;dzL9P9IU
public void setResults(List<E> results){ KUJ Lx
this.results = results; R,BJr y
} Z[nHo'
(,h2qP-;ud
public String toString(){ w1tM !4r
StringBuilder buff = new StringBuilder zP44
Xhz
G%I
.u
(); ]Kt@F0U<o
buff.append("{"); osXEzr(
buff.append("count:").append(count); Vkg0C*L_
buff.append(",p:").append(p); q}t]lD
%C
buff.append(",nump:").append(num); @:?[R&`
buff.append(",results:").append d^=)n-!T
tu}!:5xi
(results); xE8?%N U
buff.append("}"); "K(cDV Q
return buff.toString(); pWxk^qhe/
} 0#WN2f, <:
?b+Y])SJK
} ~P'.R.e
4gen,^ Ij
h^ Cm\V