Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 n$XdSh/
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 OGJ=VQA
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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 PMgQxM*h
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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 Ys-Keyg
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分页支持类: LBiowd[
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java代码: tTotPPZf}
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package com.javaeye.common.util; ?ork^4 $s
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import java.util.List; 3p=vz'
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publicclass PaginationSupport { 31~hlp;
* R%.a^R
publicfinalstaticint PAGESIZE = 30; z!fdx|PUX
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privateint pageSize = PAGESIZE; ~&1KrUu&
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privateList items; >DL/..
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privateint totalCount; '/k^C9~m
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privateint[] indexes = newint[0]; U\Ct/U&A?
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privateint startIndex = 0; lLH$`Wnv
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public PaginationSupport(List items, int 1t+%Gv^sK
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totalCount){ (Akd8}nf~
setPageSize(PAGESIZE); Q uB+vL
setTotalCount(totalCount); Q:mZ" i5
setItems(items); \/!ZA[D|E\
setStartIndex(0);
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} K"L_`.&Q
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public PaginationSupport(List items, int )R~aA#<>
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totalCount, int startIndex){ 5:UyUB
setPageSize(PAGESIZE); m4@MxQm
setTotalCount(totalCount); P*YK9Hl<
setItems(items); |Ab{H%
setStartIndex(startIndex); ym\(PCa5`
} (3VGaUlx
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public PaginationSupport(List items, int 8V-,Xig;`
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totalCount, int pageSize, int startIndex){ B oqJ
setPageSize(pageSize); MAnp{
setTotalCount(totalCount); qK?$=h.
setItems(items); K#!X><B'
setStartIndex(startIndex); %hc'dZ
} 0z7L+2#b^
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publicList getItems(){ qaG# ;
return items; \0ov[T N.>
} WS:5MI,OL
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publicvoid setItems(List items){ MS*G-C
this.items = items; OP%?dh]
} R{?vQsLk
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publicint getPageSize(){ pZk6w1d!
return pageSize; g$FEEDF
} ]Bnwk
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publicvoid setPageSize(int pageSize){ BAV>o|-K
this.pageSize = pageSize; R?pR xY
} ghAi{@s$)
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publicint getTotalCount(){ !tXZ%BP.u
return totalCount; vfw A$7N
} bA@P}M)X
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publicvoid setTotalCount(int totalCount){ A&,,9G<
if(totalCount > 0){ ]]BOk
this.totalCount = totalCount; sbo^"&%w
int count = totalCount / >MG(qi
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pageSize; S~NM\[S
if(totalCount % pageSize > 0) &|Np0R
count++; iY0>lDFm.
indexes = newint[count]; zhblLBpeE\
for(int i = 0; i < count; i++){ %gd(wzco
indexes = pageSize * @Uo6>-WF
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i; P0Z!?`e=M
} z@Hp,|Vy[
}else{ Uxu\u0*
this.totalCount = 0; zj|WZ=1*Wp
} yT8=l"-[G
} a9U_ug58
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publicint[] getIndexes(){ EU-]sTJLF
return indexes; o "z@&G" ^
} XYEv&-M`?w
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publicvoid setIndexes(int[] indexes){ A,gEM4
this.indexes = indexes; ve6w<3D@
} 58V[mlW)O0
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publicint getStartIndex(){ 5nlMrK
return startIndex; &M/>tEZ)
} %~xGkk"I
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publicvoid setStartIndex(int startIndex){ qMYe{{r
if(totalCount <= 0) 1|r,dE2k9
this.startIndex = 0; h"+ `13
elseif(startIndex >= totalCount) U/l?>lOD\
this.startIndex = indexes XT>.`, sv
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[indexes.length - 1]; Cq)IayD@
elseif(startIndex < 0) "Z=5gj
this.startIndex = 0; rQ`i8GF
else{ )!BsF'uVQ
this.startIndex = indexes 5N[9
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[startIndex / pageSize]; "KX=ow#z|
} RDqFL.-S
} W,^W^:m-x
) 0 W`
publicint getNextIndex(){ Z6p5*+
int nextIndex = getStartIndex() + jnB~sbyA
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pageSize; B~
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if(nextIndex >= totalCount) e= vsuqGT
return getStartIndex(); gD`>Twa&6
else {--0z3n>
return nextIndex; u9+kLepOT
} 0& >H^
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publicint getPreviousIndex(){ G7!W{;@I
int previousIndex = getStartIndex() - Q\ /uKQ
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pageSize; tGA :[SP
if(previousIndex < 0) ML;*e "$
return0; 7>iU1zy
else i)
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return previousIndex; O$/o'"@ /
} e:H26 SW
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} _Z5Mw+=19
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抽象业务类 z#BR5jF
java代码: Hbv6_H
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/** Zo1,1O
* Created on 2005-7-12 .EM`.
*/ ctE\ q
package com.javaeye.common.business; [Nn`l,
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import java.io.Serializable; __mF?m
import java.util.List; |rm g#;/D
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import org.hibernate.Criteria; )K &(
import org.hibernate.HibernateException; {o(j^@
import org.hibernate.Session; dOa%9[
import org.hibernate.criterion.DetachedCriteria; LL:_L<
import org.hibernate.criterion.Projections; ;b-XWK=
import MEB it
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org.springframework.orm.hibernate3.HibernateCallback; $D G?M6
import ;!(<s,c#:
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org.springframework.orm.hibernate3.support.HibernateDaoS 8OgLn?"P
5\z`-)
upport; 1GzAG;UUo6
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import com.javaeye.common.util.PaginationSupport; (o`{uj{!
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public abstract class AbstractManager extends |1j["u1
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HibernateDaoSupport { Jv^h\~*jH
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privateboolean cacheQueries = false; =>-Rnc@
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privateString queryCacheRegion; V:y'Qf2M
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publicvoid setCacheQueries(boolean u?C#4
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cacheQueries){ WPQ fhr#|
this.cacheQueries = cacheQueries; &q9T9AOS
} vam;4vyu
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publicvoid setQueryCacheRegion(String *WuID2cOI
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queryCacheRegion){ {tWf
this.queryCacheRegion = -qGa]a
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queryCacheRegion; `x*Pof!Io
} .6Pw|xu`Pw
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publicvoid save(finalObject entity){ iUN Ib
getHibernateTemplate().save(entity); F'21jy&
} p^w;kN
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publicvoid persist(finalObject entity){ /V'A%2Cl=T
getHibernateTemplate().save(entity); :/nj@X6
} EFM5,gB.m
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publicvoid update(finalObject entity){ JxM]9<a=4
getHibernateTemplate().update(entity); \XZ/v*d0
} Wi)_H$KII
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publicvoid delete(finalObject entity){ .(cw>7e3D
getHibernateTemplate().delete(entity); m+]K;}.}R
} #cI{Fe0h
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publicObject load(finalClass entity, \"P%`C
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finalSerializable id){ rX2.i7i,
return getHibernateTemplate().load 9sYMSc~Bm
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(entity, id); *nkoPVpC
} -lY6|79bF
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publicObject get(finalClass entity, n{argI8wF
) vE~'W
finalSerializable id){ B|C2lu
return getHibernateTemplate().get YJT&{jYi
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(entity, id); w;4<h8Wn5
} m[~y@7AK<
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publicList findAll(finalClass entity){ Yi%;|]
return getHibernateTemplate().find("from #A JDWelD
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" + entity.getName()); NJWA3zz
} z]_wjYn Z
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publicList findByNamedQuery(finalString 6]WAUK%h
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namedQuery){ \wz6~5R
return getHibernateTemplate /~%&vpF-L
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().findByNamedQuery(namedQuery); `ts$(u.w
} H)kwQRfu
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publicList findByNamedQuery(finalString query, $w`xvX
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finalObject parameter){ ;u_X)
return getHibernateTemplate %rL.|q9
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().findByNamedQuery(query, parameter); t&C1Oo}=3
} BUDi&|,
dd %6t
publicList findByNamedQuery(finalString query, -">;-3,K
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finalObject[] parameters){ @e.C"@G
return getHibernateTemplate 'urafE4M
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().findByNamedQuery(query, parameters); ^,TO#%$iE
} !GjQPAW
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publicList find(finalString query){ y&$A+peJ1
return getHibernateTemplate().find UmP/h@8
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(query); EH J.T~X
} Tv,[DI +
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publicList find(finalString query, finalObject ~g]Vw4pv
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parameter){ AlaW=leTe
return getHibernateTemplate().find AofKw
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(query, parameter); z\W64^'"Z
} UcHJR"M~c
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public PaginationSupport findPageByCriteria \;Biq`
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(final DetachedCriteria detachedCriteria){ \';gvr|
return findPageByCriteria +Mb.:_7'
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); +SU8 +w
} iOghb*aW
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public PaginationSupport findPageByCriteria m+[Ux{$
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(final DetachedCriteria detachedCriteria, finalint EI%89i`3^
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startIndex){ p8O2Z?\
return findPageByCriteria PJ%C N(0
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(detachedCriteria, PaginationSupport.PAGESIZE, sY&IquK^
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startIndex); BX7kO0j
} kbQ>a5`,x
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public PaginationSupport findPageByCriteria vpr.Hn
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(final DetachedCriteria detachedCriteria, finalint ^\=`edN 0
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pageSize, .Yn_*L+4*
finalint startIndex){ yR{3!{r3(
return(PaginationSupport) L#sMSVC+
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getHibernateTemplate().execute(new HibernateCallback(){ .W!i7
publicObject doInHibernate
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(Session session)throws HibernateException { `Ggbi4),
Criteria criteria = 3F2w-+L
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detachedCriteria.getExecutableCriteria(session); bq*eH (qx
int totalCount = 5U$0F$BBp
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((Integer) criteria.setProjection(Projections.rowCount n/:33DAB
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()).uniqueResult()).intValue(); G_,jgg7
criteria.setProjection )Ql%r?(F+
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(null); LZY"3Jn[nQ
List items = &V/MmmT
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criteria.setFirstResult(startIndex).setMaxResults YIYmiv5
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(pageSize).list(); }o`76rDN
PaginationSupport ps = (*iHf"=\
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new PaginationSupport(items, totalCount, pageSize, VMWf>ZU
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startIndex); 0 kW,I
return ps; Lp9E:D->
} v.qrz"98-
}, true); $=4QO
} 9\7en%( M
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public List findAllByCriteria(final >z@0.pN]7
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DetachedCriteria detachedCriteria){ E7hY8#G
return(List) getHibernateTemplate 61U09s%\0
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().execute(new HibernateCallback(){ 8Zd]wYO
publicObject doInHibernate UkFC~17P
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(Session session)throws HibernateException { GZIa4A
Criteria criteria = 7@W>E;go
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detachedCriteria.getExecutableCriteria(session); ;RlxD 4p
return criteria.list(); Jln:`!#fDf
}
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}, true); }0y"F
} ]7A'7p$Y
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public int getCountByCriteria(final G' 1'/
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DetachedCriteria detachedCriteria){ xyXa .
Integer count = (Integer) R=\IEqqsi
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getHibernateTemplate().execute(new HibernateCallback(){ v`T
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publicObject doInHibernate CAf6:^0
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(Session session)throws HibernateException { M"L=L5OH-
Criteria criteria = CTmT@A{
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detachedCriteria.getExecutableCriteria(session); Q/Rqa5LI:
return r.U`Kh]K
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criteria.setProjection(Projections.rowCount m]&SN z=
[V`r^
()).uniqueResult(); /gas2k==^
} nJ;.Td
}, true); ^B^9KEjTz
return count.intValue(); B#R|*g:x
} |uJ%5y#
} cZ3v=ke^
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用户在web层构造查询条件detachedCriteria,和可选的 [D1Up
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 ugBCBr
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PaginationSupport的实例ps。 T> p&$]OG
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ps.getItems()得到已分页好的结果集 `GLx#=Q
ps.getIndexes()得到分页索引的数组 !@"OB~
ps.getTotalCount()得到总结果数 VtohL+
ps.getStartIndex()当前分页索引 L RF103nw
ps.getNextIndex()下一页索引 cH)";]k*-
ps.getPreviousIndex()上一页索引 [-x7_=E#
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 q cno^8R
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,尤其是上面的示例代码,让我着实觉得该对我原来的分页查询做 @o.I ;}*N
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一下代码重构了。 `F6C-
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我把原本我的做法也提供出来供大家讨论吧: 4GM6)"#d
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首先,为了实现分页查询,我封装了一个Page类: aQ~s`^D
java代码: I}Q2Vu<
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/*Created on 2005-4-14*/ BerwI
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package org.flyware.util.page; "7`<~>9t.
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/** \j.:3Xr
* @author Joa Y^]rMK/;
* |K~Nw&rZ]
*/ B-ESFATc
publicclass Page { J8~haim
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/** imply if the page has previous page */ /7LR;>B j
privateboolean hasPrePage; <\FH fE
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/** imply if the page has next page */ C.QO#b
privateboolean hasNextPage; 'm9` 12H
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/** the number of every page */ ~_ a-E
privateint everyPage; Qci]i)s$js
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/** the total page number */ bN88ua}k{
privateint totalPage; h.fq,em+H
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/** the number of current page */ GH
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privateint currentPage; q,6DEz
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/** the begin index of the records by the current u-C)v*#L
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query */ Xry47a
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privateint beginIndex; w*MpX
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/** The default constructor */ KY N0
public Page(){ #o2[hibq
1i] ^{;]
} Y4(
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/** construct the page by everyPage i 3SHg\~Z
* @param everyPage (4EI-e*6
* */ 3D(0=$W
public Page(int everyPage){ y)gKxRaCS
this.everyPage = everyPage; r"R#@V\'1b
} dq[xwRU1
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/** The whole constructor */ k;L6R!V
public Page(boolean hasPrePage, boolean hasNextPage, E+JqWR5
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int everyPage, int totalPage, !v0LBe4
int currentPage, int beginIndex){ 7\q~%lDE
this.hasPrePage = hasPrePage; pHJ3nHLQ
this.hasNextPage = hasNextPage; O0y_Lm\
this.everyPage = everyPage; m9Hit8f@Q
this.totalPage = totalPage; xZv#Es%#
this.currentPage = currentPage; n.G!43@*N
this.beginIndex = beginIndex; }Z,x~G
} "FKOaQ%IH
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/** :4%k9BGAj"
* @return $p?aVO
* Returns the beginIndex. 680o)hh4m>
*/ abLnI =W`
publicint getBeginIndex(){ 5[u]E~Fl}
return beginIndex; f`=-US
} 9p2&)kb6
{jX2}
/** g'qa}/X
* @param beginIndex [1
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* The beginIndex to set. .h4 \Y A
*/ eHDN\QA 2
publicvoid setBeginIndex(int beginIndex){ $H>W|9Kg,
this.beginIndex = beginIndex; Tyf`j,=
} ]`+HO=0
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/** OH(waKq2I
* @return s+?zL~t
* Returns the currentPage. 7{I0s;R
*/ r?
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publicint getCurrentPage(){ u^qT2Ss0
return currentPage; exUu7&*:
} 7Da`
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/** ^qD$z=z-
* @param currentPage (c
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* The currentPage to set. v<(
*/ ByNn
publicvoid setCurrentPage(int currentPage){ JHTSUq
this.currentPage = currentPage; Vt&2z)Zz
} Y^EcQzLw
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/** (\YltC@q%
* @return D!-g&HBTC
* Returns the everyPage.
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*/ _C[q4?
publicint getEveryPage(){ PKg@[<g43
return everyPage; *]/zc1Q4M
} '^~{@~ ;%L
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/** * kDC liL
* @param everyPage 2?ez,*-[
* The everyPage to set. B; h"lv
*/
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publicvoid setEveryPage(int everyPage){ MH9q ;?.J
this.everyPage = everyPage; =Qj{T
} *Y7u'v
k],Q9
/** "2$fi{9
* @return ( !fKNia@S
* Returns the hasNextPage. EF}\brD1
*/ -Xm'dwm
publicboolean getHasNextPage(){ ca*DZG/
return hasNextPage; `1{ZqRFQ
} l=)xo@6
qCpp6~]Um
/** KD7dye
* @param hasNextPage Z<y I\1
* The hasNextPage to set. O-GJ-
*/ j8{i#;s!"
publicvoid setHasNextPage(boolean hasNextPage){ '+!1Y o'G
this.hasNextPage = hasNextPage; tla
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} j2.|ln"!
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/** Gm.T;fc:
* @return j94=hJVKi
* Returns the hasPrePage. KNpl:g3{<Q
*/ {9;CNsd
publicboolean getHasPrePage(){
}mq6]ZrK
return hasPrePage; xU>WEm2
} [{<`o5qR
%D}kD6=
/** lVR~Bh
* @param hasPrePage ukfQe }I
* The hasPrePage to set. `maKN \;
*/ i6tf2oqO7
publicvoid setHasPrePage(boolean hasPrePage){ >G*eNn
this.hasPrePage = hasPrePage; ," Wr"
} &5spTMw8
rc>4vB_ha
/** wh\}d4gN
* @return Returns the totalPage. 3<Zq ]jk?n
* zH4D 8@[7O
*/ ZaDyg"Tw+
publicint getTotalPage(){ ^HThN
return totalPage; v/0QOp
} B=yqW
_8riUt
/** ox>^>wR*
* @param totalPage c~$)UND^
* The totalPage to set. lL3khJ:%
*/ S)k*?dQ##R
publicvoid setTotalPage(int totalPage){ {M$1N5Eh
this.totalPage = totalPage; T`.O'!
} 5k3n\sqZA
?WUA`/[z
} }~jlj
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cr
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pb?c$n$u*
w d^':
上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 *{@Nq=fE
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个PageUtil,负责对Page对象进行构造: Ic:(Gi- %
java代码: +L|?~p`V
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/*Created on 2005-4-14*/ !/*\}\'4
package org.flyware.util.page; yZ(zdM\/sL
p8H'{f\G
import org.apache.commons.logging.Log; GR.^glG?6
import org.apache.commons.logging.LogFactory; e&F8m%t
v
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/** 7qLpZ/
* @author Joa vq0Tk
bzs
* `$<.pOm
*/ 9y8&9<#
publicclass PageUtil { 3{^9]7UC
n;Q7X>-f8`
privatestaticfinal Log logger = LogFactory.getLog $Sx'sA2
qI9z;_,gNz
(PageUtil.class); B=T'5&
S_4?K)n #
/** cJ
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* Use the origin page to create a new page UiP"Ixg6
* @param page GPv1fearl
* @param totalRecords |A9F\A->4
* @return vHc%z$-d
*/ @|m/djN5x
publicstatic Page createPage(Page page, int c(E{6g?
kGS;sB
totalRecords){ &|ex`nwc0
return createPage(page.getEveryPage(), r:'.nhe
{n.PF8A5X
page.getCurrentPage(), totalRecords); Z'W=\rl
}
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q=m'^
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/** g\:[
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* the basic page utils not including exception ^Za-`8#`L
uc\Kg1{
handler *?>T,gx}
* @param everyPage 9(7-{,c
* @param currentPage ~2N"#b&J
* @param totalRecords 2r4Uh1D~
* @return page RFc v^Xf
*/ 4Uo&d#o)C-
publicstatic Page createPage(int everyPage, int 7#a-u<HF"
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currentPage, int totalRecords){ eA ?RK.e
everyPage = getEveryPage(everyPage); QXFo1m
currentPage = getCurrentPage(currentPage); LEf^cM=>
int beginIndex = getBeginIndex(everyPage, (D&3G;0tK
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currentPage); RJ&RTo
int totalPage = getTotalPage(everyPage, =zPCrEk0
rfJz8uF%
totalRecords); k5e;fA/w
boolean hasNextPage = hasNextPage(currentPage, {9pZ)tB
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totalPage); =R|HV;9 h
boolean hasPrePage = hasPrePage(currentPage); pa3{8x{9m
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returnnew Page(hasPrePage, hasNextPage, 5H9z4-i x?
everyPage, totalPage, _8J.fT$${
currentPage, v$v-2y'%
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beginIndex); :\c ^*K(9
} 9:|{6_Y
P|E| $)m
privatestaticint getEveryPage(int everyPage){ ..5CC;B
return everyPage == 0 ? 10 : everyPage; @Uvz8*b6
} %)1?TU
AeM^73t
privatestaticint getCurrentPage(int currentPage){ "+nRGEs6
return currentPage == 0 ? 1 : currentPage; P3=G1=47U
} Bm<`n;m
bsli0FJSh'
privatestaticint getBeginIndex(int everyPage, int J!(<y(l
/Cr%{'Pzk
currentPage){ 8kIksy
return(currentPage - 1) * everyPage; l|[N42+
} I$G['`XX/
4F:\-O
privatestaticint getTotalPage(int everyPage, int G e@{_
SKN`2[ahD
totalRecords){ Ic<2QknmP
int totalPage = 0; {S)6;|ua'
Bkc4TO
if(totalRecords % everyPage == 0) fTec
totalPage = totalRecords / everyPage; vh%B[brUJ
else g:@#@1rB6
totalPage = totalRecords / everyPage + 1 ; "HIRTE;&
F/{!tx
return totalPage; ?l{nk5,?-Y
} 0[(8
zC!t;*8a
privatestaticboolean hasPrePage(int currentPage){ \gaw6S>n}
return currentPage == 1 ? false : true; /{_:{G!Q0
} IEi^kJflU
lUZ+YD4
privatestaticboolean hasNextPage(int currentPage, (?c"$|^J
0s[Hkhls
int totalPage){ J/$&NWF
return currentPage == totalPage || totalPage == FW4<5~'
</zEg3F\
0 ? false : true; wn%A4-%{
} 4+8@`f>s
bI1N@=
H7n>Vx:L-
} _B<X`L
=
Bwxd&;E
r,p%U!S<hV
a1lh-2xX
m:2^=l4
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。 V)25$aKW7
&h/Xku&0
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 m-, x<bM?
WOap+
做法如下: gM:".Ee
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 h:|qC`}
Dp9+HA9t
的信息,和一个结果集List: X \/#@T
java代码: (jE9XxQY
)SGq[B6@I
7kEn \
/*Created on 2005-6-13*/ %'pgGC"|
package com.adt.bo; 'H;*W |:-]
z2GY:<s
import java.util.List; Gd85kY@w7
bk[!8-b/a
import org.flyware.util.page.Page; WNtW|IV
i/Zd8+.n$
/** 6'f;-2
* @author Joa SmO~,2=
*/ ;2QP7PrSY
publicclass Result { M_DwUS1?
9->if/r,o
private Page page; f/?P514h
ef4 i:.
private List content; $I?"lky
$XH^~i;
/** /)O"l @ }U
* The default constructor ]`WJOx4
*/ p]c%f2E>d
public Result(){ t]G:L}AOl
super(); JBZ@'8eqi]
} I&5!=kR
]ZS
OM\}
/** 8&dF
* The constructor using fields j?QDR
* BiBOr}ZQ
* @param page YS_;OFsd
* @param content "m>81-0
*/ Tlr v={
public Result(Page page, List content){ f|(M.U-
this.page = page; (/]
J3
this.content = content; dj%!I:Q>u
} G3v5KmT
j'K/22
/** hi[pVk~B)
* @return Returns the content. q5S9C%b
*/ aw> #P
publicList getContent(){ %&bY]w
return content;
!}$$:
} 08{@rOr
/qw.p#
/** RD&PDXT4
* @return Returns the page. ybUaTD@?}b
*/ e96k{C`j0
public Page getPage(){ ^<AwG=
return page; fF kj+
} R G`1en
xkAK!uVy
/** QmIBaMI#
* @param content 0m ? )ROaJ
* The content to set. :M5l*sIO2
*/ 4KrL{Z+}
public void setContent(List content){ cM7[_*Ot<m
this.content = content; nQS|Lt_+
} {l>hMxij
Xha..r
/** !f6(Zho
* @param page Du){rVY^d
* The page to set. J$v?T$LVw
*/ PFK
'$
publicvoid setPage(Page page){ _J [P[(ab
this.page = page; pD+k*
} RpYERAgT
} >&k-'`Nw
Rws3V"{`[
5/z/>D;
!{41!O,K#
I++. ee
2. 编写业务逻辑接口,并实现它(UserManager, c[Zje7 @
E1 f\%!2l
UserManagerImpl) sn>~O4"
java代码: 6S\8$
00U> F
/H+a0`/
/*Created on 2005-7-15*/ L&OwPd
package com.adt.service; +d-NL?c
;6hOx(>`=
import net.sf.hibernate.HibernateException; dAe')N:KPI
4nz 35BLr
import org.flyware.util.page.Page; y18Y:)DkL
2VCI 1E
import com.adt.bo.Result; W+1^4::+
R_xRp&5
/** 7vj2
`+r.
* @author Joa kz7(Z'pw
*/ G 9vpt M
publicinterface UserManager { K 'I#W
lg
G<;*SYAb
public Result listUser(Page page)throws j$5LN.8J
bK-N:8Z
HibernateException; f'3$9x
B48={
} b\+`e b8_
t<?,F
B^jc3 VsR
9k[9P;"F:
GNJj=1Lsd
java代码: 5.J.RE"M
]:/Q]n^
mUx+Y ]Ep
/*Created on 2005-7-15*/ 63x?MY6
package com.adt.service.impl; t5IEQ2
iMRwp+$
import java.util.List; Ok\7y-w^
njA#@fU
import net.sf.hibernate.HibernateException; Nu~lsWyRI5
T37XBg H
import org.flyware.util.page.Page; %BB%pC
import org.flyware.util.page.PageUtil; TrR8?-
w917N4$
import com.adt.bo.Result; |)/aGZ+
import com.adt.dao.UserDAO; sds"%]rg
import com.adt.exception.ObjectNotFoundException; QoH6
import com.adt.service.UserManager; t#eTV@-
Hl
|z</*+
/** 3%=~)7cF
* @author Joa G'aDb/
*/ tcog'nAz
publicclass UserManagerImpl implements UserManager { y Fq&8 x<X
=[jXe
private UserDAO userDAO; hqkz^!rp
URbletSBQ
/** ?p8_AL'RS
* @param userDAO The userDAO to set. J`1rJ
*/ V,N%;iB}
publicvoid setUserDAO(UserDAO userDAO){ t}tEvh
this.userDAO = userDAO; `&6dnSC},P
} K8Y=S12Ti
4)o
/* (non-Javadoc) $\y'IQ%
* @see com.adt.service.UserManager#listUser gjzuG<7m
x;<W&s}(
(org.flyware.util.page.Page) CYYU7
*/ Uq`'}Vo
public Result listUser(Page page)throws 2WYPO"q
ls)%c
HibernateException, ObjectNotFoundException { {h`uV/5@`
int totalRecords = userDAO.getUserCount(); >`ZyG5
if(totalRecords == 0) W#3Q ^Z?
throw new ObjectNotFoundException v^+Sh|z/
"AGLVp.zT
("userNotExist"); WX6&oy>
page = PageUtil.createPage(page, totalRecords); L5:$U>H(
List users = userDAO.getUserByPage(page); Alw3\_X
returnnew Result(page, users); L4y4RG/SJ:
} x0:m-C
e'b(gD}
} W-zP/]Dh
mF^v ~
_n>,!vH
AbmAKA@
EG |A_m85
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 e.V:)7Uc
^eYVWQ'
询,接下来编写UserDAO的代码: LTx,cP
3. UserDAO 和 UserDAOImpl: 0F><P?5
java代码: \.#>=!Ie
)U{Qj5W+F
_~ iw[*#u
/*Created on 2005-7-15*/ (;^syJrh
package com.adt.dao; J!U}iD@occ
S\!ana])
import java.util.List; !H>R%g#28_
M?uC%x+S$_
import org.flyware.util.page.Page; xAMW-eF?d
r<Kx0`y
import net.sf.hibernate.HibernateException; _MX>#!l
.];=Pu^
/** (n9gkO&8"
* @author Joa
`~CQU
*/ HJYScwjQ;`
publicinterface UserDAO extends BaseDAO { ]1pIj
i[
3fQuoQuD"}
publicList getUserByName(String name)throws Dy8r 9
cY. bO/&l
HibernateException; ><HE;cVg?
L AAHEv
publicint getUserCount()throws HibernateException; oj_3ZsO
V-L"gnd&2
publicList getUserByPage(Page page)throws %UCr;H/
oWo-
j<
HibernateException; |R\>@Mg#B
bYQRBi
} ..'_o~Ka
9ahWIO%
^V Zk+'4
PxkOT*
GD_hhDyD
java代码: 2{G:=U
b |p)9&^r
s
15oN
/*Created on 2005-7-15*/ o.\F.C$
package com.adt.dao.impl; N `F~n%N
7 X'u6$i
import java.util.List; XaPV94
>y:,9;
import org.flyware.util.page.Page; 7!TueP0Zd
VrQmP
import net.sf.hibernate.HibernateException; 'K{Z{[s{
import net.sf.hibernate.Query; :I^;jdL
x-.?HS[
import com.adt.dao.UserDAO; ILShd)]Rw
RcU}}V
/** ' x35=@
* @author Joa !s?nJ(p
*/ I(7NQ8Hx
public class UserDAOImpl extends BaseDAOHibernateImpl VYImI>.t{
Ob`d
implements UserDAO { !AfHk|
@;?p&.W`D
/* (non-Javadoc) q0r>2c-d
* @see com.adt.dao.UserDAO#getUserByName |kV*Jc k
q6`b26
(java.lang.String) mahJSz(3
*/ c?&X?<
publicList getUserByName(String name)throws s6.M \^
KRMQtgahc
HibernateException { OCaq3_#tZ
String querySentence = "FROM user in class TOXfWEU3>
e)#J1(j_
com.adt.po.User WHERE user.name=:name"; c*L\_Vx+
Query query = getSession().createQuery iq( E'`d
EkNunCls
(querySentence); @?
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query.setParameter("name", name); jeH~<t{
return query.list();
.Blf5b
} L4z ~B!uvF
ww $
/* (non-Javadoc) qPy1;maXP
* @see com.adt.dao.UserDAO#getUserCount() kN4{13Qs*
*/ 64G[|" j D
publicint getUserCount()throws HibernateException { k" PayyAC
int count = 0; 5T2CISmu
String querySentence = "SELECT count(*) FROM ``\i58K{e
*>2W#D)b=
user in class com.adt.po.User"; dS!:JO27
Query query = getSession().createQuery *ipFwQ
MUREiL9L|
(querySentence); cir$voL
count = ((Integer)query.iterate().next 5aZ2j26
Xi,CV[L\
()).intValue(); ^c4@(]v'G
return count; :^WKT
} BB*f4z$Y%
~8P!XAU56%
/* (non-Javadoc) z(Pe,zES
* @see com.adt.dao.UserDAO#getUserByPage .e=:RkI,
ADP%QTdqFJ
(org.flyware.util.page.Page) Et/\xL
*/ @As[k2
publicList getUserByPage(Page page)throws c[4i9I3v
`e|0g"oP
HibernateException { <vh/4
String querySentence = "FROM user in class kJzoFFWo$
6qoyiT%P&
com.adt.po.User"; [] `&vWZ
Query query = getSession().createQuery _'>oXQJ
``Dq
(querySentence); s!c`=
query.setFirstResult(page.getBeginIndex()) 9c#+qH
.setMaxResults(page.getEveryPage()); pU%n]]qF
return query.list(); #W'HR
} >
BY&,4r
wq(7|!Eix
} TKY*`?ct
`YLD`(\
[nc4{0 aT'
+*T7@1
n}_JB>i~
至此,一个完整的分页程序完成。前台的只需要调用 8I8
F/47x
4c$ zKqz
userManager.listUser(page)即可得到一个Page对象和结果集对象 r(aLEJ"u?
Ov4y%Pj
的综合体,而传入的参数page对象则可以由前台传入,如果用 =K{"{5Wb
Z
X(z;|l45
webwork,甚至可以直接在配置文件中指定。 9XyYHi
l@ H
下面给出一个webwork调用示例: VsgE!/>1
java代码: X;B\Kj`n
jR22t`4
RIXMJ7e7
/*Created on 2005-6-17*/ #Jn_c0
package com.adt.action.user; 8:>1F,
P 8>d6;o($
import java.util.List; ^m"u3b4
H!nr^l'+
import org.apache.commons.logging.Log; AW_(T\P:u
import org.apache.commons.logging.LogFactory; F\AX:
import org.flyware.util.page.Page; %K`% *D
"@d[h ,TM
import com.adt.bo.Result; OQT;zqup
import com.adt.service.UserService; m~Bl*`~M
import com.opensymphony.xwork.Action; a1.Ptf eW|
HA`@7I
/** *R3f{/DK
* @author Joa I8/DR z$A
*/ ?-^m`
publicclass ListUser implementsAction{ !+4cqO
Z@&Dki
privatestaticfinal Log logger = LogFactory.getLog GXjfQ~<]
C;`XlQG `
(ListUser.class); Bj}^\Pc;}
{>,V\J0p
private UserService userService; +
33@?fl.
%Gj8F4{
private Page page; '|*?*6q
Yd= a}T
privateList users; 9^Whg~{
>teOm?@U
/* )m{Ye0!RD
* (non-Javadoc) AUNQA
* $m+sNEAa
* @see com.opensymphony.xwork.Action#execute() UIAj]
*/ S_v'hlrrT
publicString execute()throwsException{ 9Xl5@%uz?z
Result result = userService.listUser(page); &jczO-R^
page = result.getPage(); +|@rD/I6
users = result.getContent(); _5m#2u51i
return SUCCESS; w'fT=v)
} DUe&r,(4O
~L_hZso4
/** ;3@YZM'wt
* @return Returns the page. CQr<N w
*/ $w0lrh[+
public Page getPage(){ YJ/zU52JK~
return page; oY|,GvCnK
} f7~9|w&
s^|.Zr;,>
/** 3a 1 u
* @return Returns the users. o fMY,~w
*/ <[J[idY1he
publicList getUsers(){ -,aeM~
return users; O Xi@c;F
} ;Y mTw
"zY](P
/** *" 98L+
* @param page b}wC|\s
* The page to set. k({\/t3i
*/ HCJ>X;(`f?
publicvoid setPage(Page page){ }%`~T>/
this.page = page; ^o@,3__7Q
} W$o27f
X _G| hx
/** :BukUket1e
* @param users p,<&zHb>K
* The users to set. GF:`>u{C
*/ 7HJS.047
publicvoid setUsers(List users){ ?$Wn!"EC8
this.users = users; Bo+DJizu
}
6vTo*8D
deeU@x`f<
/** J.+BD\pa
* @param userService ow;R$5G
* The userService to set. EQIo5
*/ 9
ASb>A2~
publicvoid setUserService(UserService userService){ &G >(9
this.userService = userService; $W42vjr4
} qxMnp}O
} lE
;jCN
asgF1?r
b2^AP\: k
-g/hAxb5
9>#:/g/
上面的代码似乎看不出什么地方设置了page的相关初值,事实上, Ekm7 )d$
rJ'I>Q~x6
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 KZ:8[d
l
n}}5Q
么只需要: m:O(+Fl
java代码: {,j6\Cj 4
Bl1Z4` 3
8g7,2f/ }
<?xml version="1.0"?> rt +..t\
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork A?"h@-~2
L1)@z8]
1.0//EN" "http://www.opensymphony.com/xwork/xwork- [$(R#tZ+
td -3h,\\
1.0.dtd"> m>e3vu
dYojm1MQ
<xwork> ;}.Kb
{sv{847V
<package name="user" extends="webwork- rp:wQH7
<B&R6<]T
interceptors"> q cA`)j
qturd7
<!-- The default interceptor stack name =OV2 uq
h#Ce_,o
--> jB^OP1
<default-interceptor-ref "]-],K
+MO E
name="myDefaultWebStack"/> M\+* P,i
~%|G+m>
<action name="listUser" g42R 'E%
;? uC=o>Z{
class="com.adt.action.user.ListUser"> dyFKxn`,
<param ~j @UlP
8R69q:
name="page.everyPage">10</param> XqR{.jF.
<result m<3v)R[>
$)e:8jS=
name="success">/user/user_list.jsp</result> =!-5+I#e
</action> i&@,5/'-_O
Wc#:f8dr
</package> .Tm- g#
0B0G2t&hr
</xwork> <qiICb)~
uJ'9R`E ]1
n2;9geq+
c%YDt`
VvgN3e[
sdF3cX
这样就可以通过配置文件和OGNL的共同作用来对page对象设置初值 2Yyb#Ow
WhUa^
了。并可以通过随意修改配置文件来修改每页需要显示的记录数。 Xn7[n
+6%7CC 6
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 l6B.6
'4)w
T~Y g5J
W<gD6+=8
TJ2/?p\x
)Ul&1UYA
我写的一个用于分页的类,用了泛型了,hoho ye r>
x
.g-3e"@
java代码: {u]CHN`%Z
TSyzdnMvz
o#d$[oa
package com.intokr.util; 8)Tj
H'
1e$[p[
import java.util.List; L+Nsi~YVq
qU6BA\ZL
/** 712=rUI%!
* 用于分页的类<br> c57b f
* 可以用于传递查询的结果也可以用于传送查询的参数<br> S_!R^^ySG9
* s}b*5@8|tA
* @version 0.01 4 ROWz
* @author cheng (/q}mB
*/ t+}uIp42<
public class Paginator<E> { H*qD: N
privateint count = 0; // 总记录数 gO{W#%
privateint p = 1; // 页编号 "X?LAo
privateint num = 20; // 每页的记录数 !\w\ ]7ls
privateList<E> results = null; // 结果 @dhH;gt.I
~M[>m~8
/** O&P>x#w
* 结果总数 :Ba-u
*/ lIy/;hIc
publicint getCount(){ v =+k"gm6
return count; u-/3(dKt
} J:W'cH$cR
0N1' $K$\
publicvoid setCount(int count){ VEo^ :o)r
this.count = count; xDe47&qKM
} ]EX--d<_`
7+]F^
6
/** B=x~L
* 本结果所在的页码,从1开始 T.euoFU{Z
* G+Ei#:W,
* @return Returns the pageNo. xf UhSt
*/ o(SuUGW
publicint getP(){ 6Wu*.53
return p; InX{V|CW?
} ^k9rDn/AW
\1khyF'
/** ]*h&hsS0
* if(p<=0) p=1 |x[$3R1@
* r2)pAiTM*
* @param p
bn|DRy
*/ A@{ !:_55
publicvoid setP(int p){ ][N) 2_^M
if(p <= 0) /op/g]O}
p = 1; RQJ9MGw
this.p = p; .hnF]_QQ
} .kzms
9w$7VW;
/** u>
In(7\
* 每页记录数量 ^"/Dih\_
*/ 9/QS0
publicint getNum(){ GfQ^@Tl
return num; !%)L&W_
} ]LY^9eK)>{
YmA) @1@U
/** zXDd,ltm
* if(num<1) num=1 [@s=J)H
*/ 9M19UP&
publicvoid setNum(int num){ E-[:.
&
if(num < 1) /T4VJ{D
num = 1; }W)Mwu'W
this.num = num; _/8y1)I
} (T`q++
y#GCtkhi
/** )[RpZpd`*
* 获得总页数 D)RdOldr
*/ >R) F}
publicint getPageNum(){ f@#w{W,3
return(count - 1) / num + 1; l+'`BBh*]
} AzW%+ LUD
/!o1l\i=5
/** (#lm#?<)
* 获得本页的开始编号,为 (p-1)*num+1 fLc!Sn.Y
*/ V4qZc0<,H
publicint getStart(){ !4!S{#<q
return(p - 1) * num + 1; lP-kZA!
} jm~mhAE#
ge@reGfsB1
/** 'II
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* @return Returns the results. ^$ZI>L0+
*/ "&s9cO.H
publicList<E> getResults(){ |'!7F9GP
return results; sd]0Hx[
} {m>~`
sL;z"N@PK
public void setResults(List<E> results){ SIJ# ?0,
this.results = results; Ig='a"%
} hu`Lv
CD$u=E
]
public String toString(){ /7S-|%1
StringBuilder buff = new StringBuilder oa?!50d
x*k65WO\
(); Pi^ECSzQu[
buff.append("{"); `8qT['`#R
buff.append("count:").append(count); 20S9/9ll
buff.append(",p:").append(p); ;N9n'Sq4
buff.append(",nump:").append(num); _-YL!oP
buff.append(",results:").append @5JLjCN
c4S>_qH
(results); I>(;bNgNE
buff.append("}"); P<TpG0~(
return buff.toString(); V%VrAi.
} 8-W"4)@b
Uv#>d}P
} c
g3Cl[s
vEX|Q\b6'
wGZ>iLe: