Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 ,qwuLBW
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 j;r-NCBnz
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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 **CR}
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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 Y@iS_lR
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分页支持类: pki%vRY
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java代码: FV!q!D
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package com.javaeye.common.util; gJ{)-\
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import java.util.List; Ax@$+/Z!
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publicclass PaginationSupport { kTB0b*V
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publicfinalstaticint PAGESIZE = 30; 'LC1(V!_j
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privateint pageSize = PAGESIZE; $PPi5f}HD
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privateList items; sP~<*U.7
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privateint totalCount; 00y!K
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privateint[] indexes = newint[0]; q`-N7 ,$T
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privateint startIndex = 0; ^
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public PaginationSupport(List items, int 3d]S!=4H"
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totalCount){ &z3o7rif$
setPageSize(PAGESIZE); 0d&6lqTo
setTotalCount(totalCount); NI]N4[8(
setItems(items); aXYY:;
setStartIndex(0); Y.UFbrv
} 'H!Uh]!
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public PaginationSupport(List items, int 0OE:[pR
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totalCount, int startIndex){ p6@)-2^
setPageSize(PAGESIZE); n\DV3rXI9
setTotalCount(totalCount); {tZ.v@
setItems(items); m
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setStartIndex(startIndex); {\5
} =T@1@w
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public PaginationSupport(List items, int <'*LRd$1
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totalCount, int pageSize, int startIndex){ ;^*W+,4WB
setPageSize(pageSize); *)Zdz9E'1(
setTotalCount(totalCount); f6Ah6tb
setItems(items); CTa57R
setStartIndex(startIndex); q} >%8;nm
} O>,e~#!
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publicList getItems(){ pnOAs&QAm
return items; oPM96
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} }Y\%RA
EQM{
publicvoid setItems(List items){ T8g$uFo
this.items = items; /x$ nje,.
} ;_(4Q*Yx
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publicint getPageSize(){ 7:1Lol-V
return pageSize; QWYJ*
} p5iuYHKk?
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publicvoid setPageSize(int pageSize){ Rm( "=(
this.pageSize = pageSize; '=pU^Oz<}
} y)@wjH{6
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publicint getTotalCount(){ #6=
return totalCount; rILYI;'o
} lf,5w
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publicvoid setTotalCount(int totalCount){ 7<R E_/]
if(totalCount > 0){ 4r}51 N\
this.totalCount = totalCount; ?@86P|19
int count = totalCount / %ET+iIhK
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pageSize; <5051UEu
if(totalCount % pageSize > 0) 2+XAX:YD
count++; ;V!D:5U
indexes = newint[count]; @VEb{ w[H
for(int i = 0; i < count; i++){ }K(TjZR
indexes = pageSize * 5H^(2w
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i; F^:3?JA_
} 75lA%|
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}else{ N!}f}oF
this.totalCount = 0; g_bLl)g<
} ]-#DB^EQ
} uY To9A
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publicint[] getIndexes(){
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return indexes; RA 6w}:sq7
} 9(Xn>G'iT
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publicvoid setIndexes(int[] indexes){ wCBplaojJ
this.indexes = indexes; :ws<-Qy
} At;LO9T3z
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publicint getStartIndex(){ "{t$nVJ
return startIndex; P%n>Tg80M
} a<e[e>
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publicvoid setStartIndex(int startIndex){ ~xTt204S
if(totalCount <= 0) -9?]IIVb
this.startIndex = 0; ;_=&-mz
elseif(startIndex >= totalCount) o mx=
this.startIndex = indexes Mtx 4'WZ
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5
[indexes.length - 1]; V7/Rby Q
elseif(startIndex < 0) h";L
this.startIndex = 0; 53h0UL
else{ ca9X19NG
this.startIndex = indexes ckn(`I
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[startIndex / pageSize]; HzJz+ x:
} ]?4hyN
} (9)Q ' 'S
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publicint getNextIndex(){ uY*L,j^)
int nextIndex = getStartIndex() + *Pr )%
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pageSize; * 4
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if(nextIndex >= totalCount) /$m;y[[
return getStartIndex(); zQ PQ
else /dHF6yW
return nextIndex; /bmN\I
} a+QpM*n7Lq
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publicint getPreviousIndex(){ j>kqz>3
int previousIndex = getStartIndex() - y();tsWqc
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pageSize;
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if(previousIndex < 0) wd6owr
return0; &^nGtW%a 9
else iy"*5<;*DD
return previousIndex; %iB,IEw
} `D9$v(Ztr
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} :T~ [
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抽象业务类 Wp,R^d
java代码: pR_9NfV{
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/** KPki}'GO
* Created on 2005-7-12 unxqkU/<Z
*/ ]$hBMuUa
package com.javaeye.common.business; $cgcX
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import java.io.Serializable; Vvo7C!$z
import java.util.List; 6\t@)=C,Q
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import org.hibernate.Criteria; 7p[n
import org.hibernate.HibernateException; qP
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import org.hibernate.Session; '"Nr, vQo
import org.hibernate.criterion.DetachedCriteria; A}!J$V:w]
import org.hibernate.criterion.Projections; .\mj4*?/
import (<lhn
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#
org.springframework.orm.hibernate3.HibernateCallback; TA\vZGJ('
import Gm`8q}<I
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org.springframework.orm.hibernate3.support.HibernateDaoS k3|Z7eW}[
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upport; kx CSs7J/
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import com.javaeye.common.util.PaginationSupport; I =#$8l.*
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public abstract class AbstractManager extends ~6gPS
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HibernateDaoSupport { [>9is=>o.
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privateboolean cacheQueries = false; =pr7G+_u
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privateString queryCacheRegion; A}w/OA97RO
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publicvoid setCacheQueries(boolean atzX;@"K
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cacheQueries){ dWW.Y*339
this.cacheQueries = cacheQueries; 6~+emlD
} O&&~NXI\
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publicvoid setQueryCacheRegion(String HKe K<V
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queryCacheRegion){ Lj7AZ|k
this.queryCacheRegion = ^^Vg~){4
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queryCacheRegion; VaPG-n>Vf
} eH,or ,r
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publicvoid save(finalObject entity){ j1Ezf=N6`
getHibernateTemplate().save(entity); 4z)]@:`}z
} ?4uL-z](V
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publicvoid persist(finalObject entity){ d5 -qZ{W
getHibernateTemplate().save(entity); r<\u6jF
} }2oc#0
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publicvoid update(finalObject entity){ M\=2uKG#
getHibernateTemplate().update(entity); ,u m|1dh
} DNi+"[~&P
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publicvoid delete(finalObject entity){ @nf`Gw ;
getHibernateTemplate().delete(entity); [ hsds\
} `u\n0=go
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publicObject load(finalClass entity, 31)&vf[[
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finalSerializable id){ d5d@k
return getHibernateTemplate().load Y*hCMy;
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(entity, id); 2SLU:=<3
} (sj,[
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publicObject get(finalClass entity, ]^]wP]R_
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finalSerializable id){ }WV:erg`
return getHibernateTemplate().get `X8F`5&U\f
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(entity, id); TC"<g
} $xQL]FmS
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publicList findAll(finalClass entity){ 05[SC}MCA
return getHibernateTemplate().find("from %)wjR/o
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" + entity.getName()); 2pAW9R#UV-
} v0y(58Rz.
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publicList findByNamedQuery(finalString /tLVX} &
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namedQuery){ #;<Y[hR{P
return getHibernateTemplate Js;h%
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().findByNamedQuery(namedQuery); I_BJH'!t
} ~s{$WL&
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publicList findByNamedQuery(finalString query, E'8;10s
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finalObject parameter){ KmF]\:sMD
return getHibernateTemplate E.f%H(b
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().findByNamedQuery(query, parameter); @WB@]-+J
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} nP$9CA
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publicList findByNamedQuery(finalString query, c%&>p||
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finalObject[] parameters){ y}H!c;
return getHibernateTemplate \Cj B1]I
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().findByNamedQuery(query, parameters); Uz7<PLxd
} Q.[0ct
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publicList find(finalString query){ t^L]/$q
return getHibernateTemplate().find *`U~?q}
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(query); :pUtSs7p}
} UI#h&j5pW
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publicList find(finalString query, finalObject =#\:}@J5I
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parameter){ Q20%"&Xp]
return getHibernateTemplate().find he4(hX^
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(query, parameter); M`>E|"<
} 1"g<0
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public PaginationSupport findPageByCriteria Lv%x81]K
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(final DetachedCriteria detachedCriteria){ $C\BcKlmv
return findPageByCriteria :%.D78&
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); z @Y;r=v
} Vc2`b3"Br
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public PaginationSupport findPageByCriteria ]tD]Wx%
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(final DetachedCriteria detachedCriteria, finalint =}*0-\QG
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startIndex){ Dj +f]~
return findPageByCriteria "fI6Cpc
'%D7C=;^
(detachedCriteria, PaginationSupport.PAGESIZE, c:0L+OF}xY
JO;Uus{?
startIndex); w@b)g
} ! z**y}<T
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public PaginationSupport findPageByCriteria E3i4=!Y
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(final DetachedCriteria detachedCriteria, finalint !?XC1xe~R
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pageSize, FtZ?C@1/
finalint startIndex){ >bxS3FCX
return(PaginationSupport) YN,A)w:]
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getHibernateTemplate().execute(new HibernateCallback(){ q@&6#B
publicObject doInHibernate R@0R`Zs
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(Session session)throws HibernateException { R2;
Criteria criteria = 1,~D4lD|
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detachedCriteria.getExecutableCriteria(session); /,dz@
int totalCount = 8QK&_n*
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((Integer) criteria.setProjection(Projections.rowCount \8
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()).uniqueResult()).intValue(); @oNXZRg6
criteria.setProjection 0erNc'e
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(null); 9z0p5)]n>
List items = Z.WW(C.
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criteria.setFirstResult(startIndex).setMaxResults VQs5"K"
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(pageSize).list(); :U\tv[
PaginationSupport ps = ,bd_:
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new PaginationSupport(items, totalCount, pageSize, SKtr tm
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startIndex); ~dSr5LUD
return ps; ZG:{[sT
} s.#`&Sd>
}, true); z{6Z
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} yX5\gO6G
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public List findAllByCriteria(final H.;Q+A,8^
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DetachedCriteria detachedCriteria){ ZC?Xqp
return(List) getHibernateTemplate n|hNM?v
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().execute(new HibernateCallback(){ i1085ztN
publicObject doInHibernate H::bwn`Vc
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(Session session)throws HibernateException { @d_M@\r=j
Criteria criteria = KXrjqqXs
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detachedCriteria.getExecutableCriteria(session); Y@v>FlqI{
return criteria.list(); K@2),(z
} Fcx&hj1gQ
}, true); }qUX=s
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} $j~RWfw-
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public int getCountByCriteria(final I'Hf{Erw
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DetachedCriteria detachedCriteria){ ni<(K
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Integer count = (Integer) Ni>[D"|
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getHibernateTemplate().execute(new HibernateCallback(){ [7-?7mp!B
publicObject doInHibernate y}
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(Session session)throws HibernateException { 0]L"H<W
Criteria criteria = k+/6$pI
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detachedCriteria.getExecutableCriteria(session); [UR-I0 s!/
return "4Nt\WQ
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criteria.setProjection(Projections.rowCount jdN`mosJ
}vuARZ>
()).uniqueResult(); *a)n62
} `V1]k_h
}, true); ]GS bjHsO
return count.intValue(); R_KH"`q
} LeQjvW9y
} "Q<MS'a
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用户在web层构造查询条件detachedCriteria,和可选的 1 zZlC#V
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 =]t|];c%
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PaginationSupport的实例ps。 Xvv6~
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ps.getItems()得到已分页好的结果集 _!6jR5&r,
ps.getIndexes()得到分页索引的数组 f3;5Am
ps.getTotalCount()得到总结果数 >?b!QU*a
ps.getStartIndex()当前分页索引 #WuBL_nZ~
ps.getNextIndex()下一页索引 `uFdwO'DD
ps.getPreviousIndex()上一页索引 s7<AfaJPF
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 XSDpRo
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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 Ri{=]$
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一下代码重构了。 |>Vb9:q9Po
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我把原本我的做法也提供出来供大家讨论吧: ixFi{_
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首先,为了实现分页查询,我封装了一个Page类: "g|#B4'e
java代码: NUZl`fu1Z4
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/*Created on 2005-4-14*/ M+>u/fldV
package org.flyware.util.page; 3Ul*QN{6
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/** 3<!7>]A
* @author Joa n]9$:aLZ
* Ey2^?
*/ 'V {W-W<
publicclass Page { QY/w
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/** imply if the page has previous page */ \<' ?8ri#
privateboolean hasPrePage; DF= *_,2/
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/** imply if the page has next page */ \Z/@C lCm
privateboolean hasNextPage; vt8By@]:
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/** the number of every page */ ~ a:
privateint everyPage; vQCy\Gi
}j%5t ~Qa
/** the total page number */ \85i+q:LuA
privateint totalPage; gJXaPJA{
+rd+0 `}C
/** the number of current page */ V&5wRz+`W
privateint currentPage; = [E
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/** the begin index of the records by the current Tbq;h?D
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query */ *pq\MiD/
privateint beginIndex; !a`&O-ye
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/** The default constructor */ ^sw?gH*
public Page(){ EwN}l
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} ~Y;*u]^
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/** construct the page by everyPage K-4PI+qQ\
* @param everyPage _b 0&!l<
* */ 6Oq7#3]
public Page(int everyPage){ UNYqft4
this.everyPage = everyPage; #e"[^_C@!
} "sTRS*
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/** The whole constructor */ @]j1:PN-
public Page(boolean hasPrePage, boolean hasNextPage, A"]YM'.
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int everyPage, int totalPage, :X=hQ:>P
int currentPage, int beginIndex){ >7|VR:U?B
this.hasPrePage = hasPrePage; Ac@VGT:9
this.hasNextPage = hasNextPage; s[jTP(d)8
this.everyPage = everyPage; uT"rq:N
this.totalPage = totalPage; G\i9:7 `
this.currentPage = currentPage; 9w"*y#_
this.beginIndex = beginIndex; zPO9!?7|
} *wearCPeJ
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/** 8tL~FiHb"
* @return N7"W{"3D
* Returns the beginIndex. L0,'mS
*/ 2G7Wi!J
publicint getBeginIndex(){ &d!GImcxQ
return beginIndex; b}`TLn
} [JiH\+XLPs
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/** 1zv'.uu.,
* @param beginIndex :;}P*T*PU
* The beginIndex to set. %J(:ADu]
*/ la!~\wpa
publicvoid setBeginIndex(int beginIndex){ dPlV>IM$z
this.beginIndex = beginIndex; T)/eeZ$
} FPz9N@M%Q
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/** Ui~>SN>s
* @return 1}x%%RD_
* Returns the currentPage. K?;DMUSY\
*/ afVT~Sf{
publicint getCurrentPage(){ (QEG4&9
return currentPage; +7Gwg
} )nkY_'BV
L *wYx|
/** J1k>07}|
* @param currentPage K-v#.e4
* The currentPage to set. D*jM1w_`
*/ t.<i:#rj>l
publicvoid setCurrentPage(int currentPage){ 4?kcv59
this.currentPage = currentPage; 9[4xFE?|
} Wr
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/** >MZ/|`[M
* @return h p1Bi
* Returns the everyPage. <'u'#E@"sl
*/ ?,z}%p
publicint getEveryPage(){ $Sq:q0
return everyPage; )lkjqFQ(
} IGl9g_18
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/** J.a]K[ci
* @param everyPage BmT! aue
* The everyPage to set. i!Ba]n
*/ Gc?a +T
publicvoid setEveryPage(int everyPage){ _BufO7`.
this.everyPage = everyPage; K(4_a``05
} 5BIY<B+i
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/** dtDFoETz
* @return /ZX}Nc g
* Returns the hasNextPage. 6ujWNf
*/ cAw/I@jG
publicboolean getHasNextPage(){ Yy8g(bU
return hasNextPage; 4W75T2q#
} j 7B!h|
/vt3>d%B;
/** 6tZI["\
* @param hasNextPage KNl$3nX
* The hasNextPage to set. 0GL M(JmK
*/ ~%oR[B7=|
publicvoid setHasNextPage(boolean hasNextPage){ Eci\a]
this.hasNextPage = hasNextPage; P55fL-vo|}
} }>\C{ClI
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/** ctQ/wrkU
* @return :FF=a3/"6
* Returns the hasPrePage. 4euO1=
*/ %#+Hl0,Tt
publicboolean getHasPrePage(){ vN $s|R'@
return hasPrePage;
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} (Ld i|jL
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/** TeQV?ZQ#}
* @param hasPrePage rv;3~'V
* The hasPrePage to set. :RYTL'hes
*/ x`s>*^
publicvoid setHasPrePage(boolean hasPrePage){ 7<4qQ.deE
this.hasPrePage = hasPrePage; U$g?!Yl0
} \8tsDG(1 '
H,J8M{
/** l;U?Z'n
* @return Returns the totalPage. )oZ dj`
* e20-h3h+
*/ {
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publicint getTotalPage(){ ooGM$U
return totalPage; Gj*9~*xm(
} %O<BfIZ
Cx"sw
}
/** xno\s.H%]
* @param totalPage =1!
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* The totalPage to set. _F{C\}
*/ ~&O%N
publicvoid setTotalPage(int totalPage){ reVgqYp{{-
this.totalPage = totalPage; PF2nLb2-
} G$PE}%X
k)u[0}
} =Qq+4F)MD
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6@f-Glwg
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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 p_ =z#
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个PageUtil,负责对Page对象进行构造: $>gFf}#C
java代码: E^PB)D(.
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/*Created on 2005-4-14*/ 8t`?#8D}
package org.flyware.util.page; 0x7'^Z>-oe
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import org.apache.commons.logging.Log; e!`i3KYn"
import org.apache.commons.logging.LogFactory; l6B@qYLZ
3$w65=
/** ^aQ"E9
* @author Joa g}i61(
* V)^+?B)T
*/ +p^u^a
publicclass PageUtil { neh(<>
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privatestaticfinal Log logger = LogFactory.getLog !wNO8;(
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(PageUtil.class); l0]
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/** wzaV;ac4K
* Use the origin page to create a new page ,Q,^3*HX9}
* @param page Q?T]MUY(L
* @param totalRecords hph4 `{T
* @return h![#;>(
*/ 8fb'yjIC
publicstatic Page createPage(Page page, int >7r!~+B"9'
,[Fb[#Qqb
totalRecords){ l,:F
return createPage(page.getEveryPage(), Q&&@v4L
JRFtsio*
page.getCurrentPage(), totalRecords); +V+a4lU14
} /=h` L,
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/** *A< 5*Db:F
* the basic page utils not including exception F?cK-.
BHw, 4#F1;
handler *H122njH+T
* @param everyPage h~26WLf.
* @param currentPage :EH=_"
* @param totalRecords S$3JMFA
* @return page :KN-F86i
*/
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publicstatic Page createPage(int everyPage, int C?Ucu]cW
:LTN!jj
currentPage, int totalRecords){ __@BUK{ q
everyPage = getEveryPage(everyPage); YP9^Bp{0
currentPage = getCurrentPage(currentPage); 9cgUT@a
int beginIndex = getBeginIndex(everyPage, zJXplvaL;
C>~TI,5a3
currentPage); .-=vx r
int totalPage = getTotalPage(everyPage, uMv1O{
*kVV+H<X|b
totalRecords); b\ PgVBf9
boolean hasNextPage = hasNextPage(currentPage, @KA4N`
V:27)]q
totalPage); dd["dBIZ '
boolean hasPrePage = hasPrePage(currentPage); 2Hdu:"j
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returnnew Page(hasPrePage, hasNextPage, fatf*}eln
everyPage, totalPage, >MK98(F
currentPage, 9Ee'Cm
sr}E+qf
beginIndex); i&k7-<
} 6Iw\c
TKjFp%
privatestaticint getEveryPage(int everyPage){ ~4"dweu?
return everyPage == 0 ? 10 : everyPage; o.\oA6P_
} !wp3!bLp
<1pEwI~
privatestaticint getCurrentPage(int currentPage){ }i2V.tVB-
return currentPage == 0 ? 1 : currentPage; E e]-qN*8
} +O5hH8<&b
V+~Nalm O
privatestaticint getBeginIndex(int everyPage, int +>9Q/E
ap~^Ty<>
currentPage){ Ewm9\qmg
return(currentPage - 1) * everyPage; GF
WA>5n'
} s79r@])=
y?0nI<}}HK
privatestaticint getTotalPage(int everyPage, int <1%$Vq
tu?MY p;
totalRecords){ tjnIN?YT
int totalPage = 0; 80;(Gt@<"
}`"6aM
if(totalRecords % everyPage == 0) X?$_Sd"G+5
totalPage = totalRecords / everyPage; Vg23!E
else njw|JnDv
totalPage = totalRecords / everyPage + 1 ; Tf)*4O4@'
fAmz4
return totalPage; Z6pUZ[j,
} Bj~+WwD)QR
8Eq7Sa
privatestaticboolean hasPrePage(int currentPage){ EzIGz[
return currentPage == 1 ? false : true; "vGW2~*)
} D-4f.Tq4#
JLi|Td"1%
privatestaticboolean hasNextPage(int currentPage, ty`DJO=Omj
CP{cAzHO
int totalPage){ 'QIqBU'~
return currentPage == totalPage || totalPage == bF(f*u
03(4 x'z
0 ? false : true; \4#W xZ
} 4&f3%eTi
Rh |nP&6
Z<phcqEi8
} bTu9;(
C
$JmzrE
Y<rU#Z #T
Uwi7)
q]M0md
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 X76e&~
]tDDq=+v
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 ~,~eoW7
k'"%.7$U!
做法如下: {GO#.P"
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 +{UcspqM
x;')9/3
的信息,和一个结果集List: qv*^fiT
java代码: hL5|69E
nLiY%x`S
RGU\h[
/*Created on 2005-6-13*/ 3 9|MX21k
package com.adt.bo; &I406Z f7y
;'Nd~:-]
import java.util.List; QwJyY{O`
d M-%{
import org.flyware.util.page.Page; 9E6R0D}
+U.I( 83F
/** 1r7y]FyH$
* @author Joa [sb[Z:
*/ MxGW(p
publicclass Result { #u
+ v_
_,d~}_$`i
private Page page; @fV9
S"TcM
69 o7EA
private List content; .}`Ix'.
l0hlM#
/** _7)n(1h[3b
* The default constructor ->{KVPHe{
*/ +H2-ZXr
public Result(){ d'I"jZ
super(); w'3iY,_ufC
} -S+zmo8
{u9}bx'<
/** f4Rf?w*
* The constructor using fields p[lA\@l[
* GDy9qUV
* @param page gGS=cdlV
* @param content Rx|;=-8zg
*/ i2^>vYCsl
public Result(Page page, List content){ Y]5l.SV
this.page = page; Zsh9>]ML
this.content = content; Pco'l#:
} W 8!Qv8rf
lu6(C
/** $lut[o74
* @return Returns the content. n\.V qe
*/ ^<-+@v*
publicList getContent(){ zNuJj L
return content; t!\tF[9e
} XF_pN[}
lUiL\~Gq
/** f>Jr|#k
* @return Returns the page. ;xs"j-r/
*/ 50C
public Page getPage(){ ]]juN
return page; @Pzu^
} -[DOe?T
"v4B5:bmqW
/** 5Zva:
* @param content uL/m u<
* The content to set. Ji 0
tQV
*/ FjI`uP
public void setContent(List content){ 1~QPG\cdIX
this.content = content; u4|$bbig
} y<bDTeoo
Iy3GE[
/** 7
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* @param page FtC^5{V+V
* The page to set. dmN&+t
*/ g2/8~cn8z
publicvoid setPage(Page page){ {T
Ug.%u
this.page = page; t3Y:}%M
} }I6vqG
} XNu^`Ha
f:.I0 ST
X/M4!L}\
_OC<[A
*GN#
r11d
2. 编写业务逻辑接口,并实现它(UserManager, Clb@$,
om-omo&,X=
UserManagerImpl) H&}pkrH~
java代码: ZEO,]$Yi7
0tB0@Wj
y%bF&
/*Created on 2005-7-15*/ yN
s,Ll~
package com.adt.service; Vr1<^Ib
e2W".+B1
import net.sf.hibernate.HibernateException; ^4Ah_U
9Ly]DZ;L
import org.flyware.util.page.Page; qH 6>!=00
"{Eta
import com.adt.bo.Result; \<6CZ
usL*
x9i
/** f[^Aw(o
* @author Joa 84 pFc;<
*/ 2Jmz(cH%
publicinterface UserManager { -n<pPau2
Y~E`9
public Result listUser(Page page)throws 3%;a)c;D
:7?FF'u
HibernateException; qXtC^n@x
;K&o-y
} WPG(@zD
M*HnM(
f\>M'{cV
+|89>}w4
@w !PaP
java代码: &;sP_ h
FA3~|Zg
y(pks$
/*Created on 2005-7-15*/ EeRX+BM,
package com.adt.service.impl; 8j\cL'
V2|aN<Sx<
import java.util.List; oVe|Mss6
`eCo~(Fy
import net.sf.hibernate.HibernateException; K_ ~"}
^ tg<K
import org.flyware.util.page.Page; wInh~p
import org.flyware.util.page.PageUtil; %vhnl'
Z//+Gw<'
import com.adt.bo.Result; sAD}#Zw$
import com.adt.dao.UserDAO; )i^<r ;_z
import com.adt.exception.ObjectNotFoundException; vv+z'(l
import com.adt.service.UserManager; QR0Q{}wbqU
0C6-GKbZ
/** Hi1JLW,
* @author Joa bPt!yI:
*/ 2M'[,Xe
publicclass UserManagerImpl implements UserManager { A/KJqiag
qC:raH_:
private UserDAO userDAO; QTXt8I
y)!5R 3b
/** $ ,}E
* @param userDAO The userDAO to set. 5VAK:eB
*/ t+iHQfuP9A
publicvoid setUserDAO(UserDAO userDAO){ 9!}8UALD
this.userDAO = userDAO; $!yW_HTx
} 1@1U/ss1
=i*;VFc
/* (non-Javadoc) 0dhaAq`k
* @see com.adt.service.UserManager#listUser usCt#eZK
aV|hCN~
(org.flyware.util.page.Page) LS*y
*/ YLv'43PL
public Result listUser(Page page)throws ,+xB$e
O-I[igNl
HibernateException, ObjectNotFoundException { jQ
int totalRecords = userDAO.getUserCount(); &Ao+X=qw
if(totalRecords == 0) ?ztkE62t
throw new ObjectNotFoundException dCk3;XU
\2"I;
("userNotExist"); JYd 'Jp8bP
page = PageUtil.createPage(page, totalRecords); 6ne7]RY
List users = userDAO.getUserByPage(page); i?g5_HI
returnnew Result(page, users); QpA/SmJ
} 71gT.E
E!l!OtFL
} ^o1*a&~J@
$#S&QHyEe
b+6\JE^Mz
SO(NVJh
ZR]25Yy
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 )~] (&
NzOo0tz:
询,接下来编写UserDAO的代码: _5# y06Q
3. UserDAO 和 UserDAOImpl: Oz`BEyb]{
java代码: e`TH91@
,\ k(x>oy
r)~ T@'y
/*Created on 2005-7-15*/ Vq\`+&A
package com.adt.dao;
G]i/nB
s<_)$}
import java.util.List; }O^zl#
K]0:?h;%Ld
import org.flyware.util.page.Page; f[a}aZ9)
ahOM CZF|
import net.sf.hibernate.HibernateException; ,Pjew%
`t9?=h!
/** dEA6
* @author Joa O6/f5
*/ 4VCOKx
publicinterface UserDAO extends BaseDAO { e<h~o!za
-
'W++tH=
publicList getUserByName(String name)throws An"</;HU
VG5+CU
HibernateException; PuT@}tw
FCuB\Q
publicint getUserCount()throws HibernateException; #9xd[A: N
7-T{a<g
publicList getUserByPage(Page page)throws Q&g^c2
d%,eZXg'
HibernateException; WKIoS"?-F
DRgTe&+
} dhr3,&+T2
CS-uNG6
ayD}r#7
}mdAM6
}'/`2!lY
java代码: I'iGt~4$
5nO% Ke=
{v2|g
/*Created on 2005-7-15*/ _D_LgH;}
package com.adt.dao.impl; ^8Q62
G *;a^]-
import java.util.List; 1ilBz9x*!
;Q[mL(1:
import org.flyware.util.page.Page; Upd3-2kr&J
#K Xa&C
import net.sf.hibernate.HibernateException; ;b(p=\i
import net.sf.hibernate.Query; ,%Up0Rr,
&PK\|\\2
import com.adt.dao.UserDAO; Q|L9gz[?
rJ{O(n]j
/** ,JN8f]a^"g
* @author Joa yi%-7[*]=
*/ R Yl>
public class UserDAOImpl extends BaseDAOHibernateImpl cwWodPNm
R>"OXFaE
implements UserDAO { )5U[o0td
Kt|1&Gk
/* (non-Javadoc) /_Z652@
* @see com.adt.dao.UserDAO#getUserByName r*_ZJ*h[
ux3<l +jv^
(java.lang.String) wG<(F}VX
*/ :!b'Vk
publicList getUserByName(String name)throws 5<j%EQN|D
FR!? #!
HibernateException { 7{qy7,Gp
String querySentence = "FROM user in class Y=n4K<
!M]\I &
com.adt.po.User WHERE user.name=:name"; sZm$|T0
Query query = getSession().createQuery i21Gw41p:
i?e`:}T
(querySentence); $Gv9m
query.setParameter("name", name); /BV03B
return query.list(); x61 U[/r
} H;fxxu`cS
z0*_^MH
/* (non-Javadoc) }HYjA4o\A
* @see com.adt.dao.UserDAO#getUserCount() jR#~I@q^
*/ _({A\}Q|
publicint getUserCount()throws HibernateException { mJ`A_0
int count = 0; {aJJ`t
String querySentence = "SELECT count(*) FROM CL}{mEr}
(B-43!C
user in class com.adt.po.User"; `8>Py~
Query query = getSession().createQuery
9*=W- v
e|D;OM
(querySentence); mL`5 uf
count = ((Integer)query.iterate().next Eb>78k(3I)
(S`2[.j
()).intValue(); mzc
4/<th
return count; `o?Ph&p}
} 1=a>f"cyf
+_xOLiu
/* (non-Javadoc) Yx inE`u~
* @see com.adt.dao.UserDAO#getUserByPage S^<g_ q
L%c0 Z@[~
(org.flyware.util.page.Page) b2=0}~LK
*/ *"r~-&IL
publicList getUserByPage(Page page)throws o9S+6@
Kmv+1T0,
HibernateException { 9Xo[(h)5d
String querySentence = "FROM user in class gzD@cx?V
j>/ ,$H
com.adt.po.User"; U Gpu\TB
Query query = getSession().createQuery x5WW--YR+
4[-*~C|W5
(querySentence); p6XtTx
query.setFirstResult(page.getBeginIndex()) xvSuPP4 m
.setMaxResults(page.getEveryPage()); &gE 75B
return query.list(); mA@Me7m}
} P?]aWJ
{]]|5
\F
} P7f,OY<@%o
LtKI3ou
FSbHn{@
NwR}yb6
Z@%HvB7
至此,一个完整的分页程序完成。前台的只需要调用 9bq<GC'eX8
eDZ8w
userManager.listUser(page)即可得到一个Page对象和结果集对象 0W()lQ
Q;J`Q wkH
的综合体,而传入的参数page对象则可以由前台传入,如果用 6q6FB
%F*|;o7 s
webwork,甚至可以直接在配置文件中指定。 *d',Vuv&[
}Lw>I94e
下面给出一个webwork调用示例: c9nH}/I_
java代码: .ol'.t,S
@(i!YL
{?}*1,I
/*Created on 2005-6-17*/ *8tI*Pus
package com.adt.action.user; FsGlJ
9A7@
5F
import java.util.List; h}Wdh1.M3
H<G4O02i_
import org.apache.commons.logging.Log; ?}Lg)EFH
import org.apache.commons.logging.LogFactory; o!r8{L
import org.flyware.util.page.Page; <JwX_\?ln
!;!~n`
import com.adt.bo.Result; b2b75}_A
import com.adt.service.UserService; `g1iCF
import com.opensymphony.xwork.Action; Y05P'Q
}/,CbKi,+
/** on7I
l
* @author Joa ' 2-oh
*/ OcSEo7W
publicclass ListUser implementsAction{ Q!FLR>8
#s%-INcR
privatestaticfinal Log logger = LogFactory.getLog %&\ jOq~
Lh-`OmO0>F
(ListUser.class); WmQ01v
(?b@b[D~4
private UserService userService; A;u" <KG?
5]1h8PW!Y
private Page page; pBC<u
xT)psM'CL
privateList users; .\qj;20W
90Hjx>[
/* 2w$twW-
* (non-Javadoc) oiX"Lz{
* Sj(F3wY
* @see com.opensymphony.xwork.Action#execute() STA4 p6
*/ ='E$-_
publicString execute()throwsException{ oQj=;[
Result result = userService.listUser(page); -gz0md|Y
page = result.getPage(); KZBrE$@%5
users = result.getContent(); do
^RF<G
return SUCCESS; :` $@}GI
} pNE(n4v
~/tKMS6T
/** }p9F#gr
* @return Returns the page. +/+P\O
*/ D=)f
)-u'
public Page getPage(){ da$BUAqU
return page; 8%~t
} VIR. yh
,A5) <}
/** ]> Y/r-!
* @return Returns the users. L {ymI)Y^
*/ 7CB#YP?E
publicList getUsers(){ u.|~$yP.!
return users; EC?Efc+O
} 5H:@8,B
Q:|w%L*E
/** ;#G%U!p
* @param page :'r6TVDW
* The page to set. Y+/lX 6'
*/ mi2o1"Jd$`
publicvoid setPage(Page page){ 8"vwU@cfC
this.page = page; >LF&EM]
} !
qJI'+_
e^$j5jV
/** ELh3^
* @param users kYxS~Kd<
* The users to set. ER{3,0U
*/ $'[q4 wo<
publicvoid setUsers(List users){ \`xkp[C
this.users = users; ]9S`[c$
} Z]:BYX'
u&TdWZe
/** 2#_38=K=@
* @param userService 5`E))?*"Pe
* The userService to set. \T-~JQVj
*/ 8Xm@r#Oy5
publicvoid setUserService(UserService userService){ u=qPzmywt
this.userService = userService;
c!uW}U_z
} chAan~r[*
} (=T$_-Dj`}
i!MwBYk
c/u_KJFF-n
Eb.;^=x
Dr"/3xm
上面的代码似乎看不出什么地方设置了page的相关初值,事实上, mPVE?jnR^0
".2A9]_s
可以通过配置文件来进行配置,例如,我想每页显示10条记录,那 4^!4eyQ^
w&lZ42(mF
么只需要: 5su.+4z\
java代码: f(u&XuZ
]RFdLV?
g<[rH%\6fg
<?xml version="1.0"?> E:VGji7s
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork <uF [,
_q Tpy)+
1.0//EN" "http://www.opensymphony.com/xwork/xwork- pX<a2FP
S>ugRasZ$
1.0.dtd"> Vf{2dZZ{1
sS,#0Qt.
<xwork> R.7#zhC`4
a%~yol0wO7
<package name="user" extends="webwork- u+% tPe
IM-`<~(I#
interceptors"> =wA5P@
Rk<%r k
<!-- The default interceptor stack name U7%28#@
4=p@2g2"H
--> }#b
%"I0
<default-interceptor-ref b4~H3|
H,>#|F
name="myDefaultWebStack"/> 'H=weH
Gm&2R4 )EP
<action name="listUser" U4_"aT>My
gGKKs&n7
class="com.adt.action.user.ListUser"> : z~!p~
<param bc}dYK3$q
@
u1Q-:
name="page.everyPage">10</param> J#7(]!;F
<result R[yL_>
a8h]n:!
name="success">/user/user_list.jsp</result> G6Q4-kcK
</action> `Ei"_W
m,NMTyJoz
</package> Mj~${vj
`45d"B
I
</xwork> POBpJg
_
+KmNfR
glor+
>RR<eYu7m
/`R dQ<($
D_aR\
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 /w~C~6z
@!
>i8~dEbB
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。 @Qo,p
A1<k1[5fJ
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 MYTS3(
`D)S-7BR
KF$ %q((
R ]=SWE}U
MhH);fn
我写的一个用于分页的类,用了泛型了,hoho Z1]"[U[;
q)Je.6$#X
java代码: WOH9%xv
{U
P_i2`.
oYqE*mA
package com.intokr.util; \G=bj;&eF
\DyKtrnm%
import java.util.List; gDhl-
/'+4vXc@
/** 0=,'{Vz}A
* 用于分页的类<br> &enlAV'#)O
* 可以用于传递查询的结果也可以用于传送查询的参数<br> s=\7)n=,M
* em/Xu
* @version 0.01 2B'^`>+8S
* @author cheng *dVD
*/ F`D9Zfd
public class Paginator<E> { Nz @8
privateint count = 0; // 总记录数 y<uE-4
privateint p = 1; // 页编号 x9\J1\
privateint num = 20; // 每页的记录数 D'?]yyrf
privateList<E> results = null; // 结果 83xd@-czgh
TA9dkYlE/
/** YUS?]~XC7x
* 结果总数 165WO}(;/
*/ 2HVCXegq
publicint getCount(){ |lHFo{8"
return count; KF4see;;
} 9!S^^;PN&
Fi k@hu
publicvoid setCount(int count){ Q^ q=!/qQ
this.count = count; Y(W{Jd+
} rUvwpP"k
2q|_Dma
/** _"v~"k 90^
* 本结果所在的页码,从1开始 4Qhx[Hv>(
* aZC*7AK
* @return Returns the pageNo. _3zU,qm+
*/ zCM^r <Kr
publicint getP(){ !
fX9*0L
return p; %g5jY%dg.r
} @6[x%j/!bt
l^BEFk;
/** ?PYNE
* if(p<=0) p=1 V!}L<cN
* yx 7loy$[
* @param p ;HT0w_,
*/ F94V 5_[
publicvoid setP(int p){ !~tnti6
if(p <= 0) YN`UTi\s
p = 1; x:vrK#8D>
this.p = p; n=r=u'oi
} 0 c,bet{m
gBfX}EK7F
/** }P16Xb)p
* 每页记录数量 % M+s{ l
*/ /;b.-v&
publicint getNum(){ x1:vUHwC
return num; lW&[mnR
} 6WCmp,*
wbl${@4
/** 8\P
JSr
* if(num<1) num=1 i:R!T,
*/ \S'cWB
publicvoid setNum(int num){ oNrEIgaA(+
if(num < 1) Ep,1}Dx
num = 1; Za34/ro/T
this.num = num; ?#U0eb5u
} 0\QYf0o
|@OJ~5H/{
/** Mn-<5 1.%
* 获得总页数 _y|[Z;
*/ AK%=DVkM
publicint getPageNum(){ R+k=Ea&x
return(count - 1) / num + 1; a_xQ~:H
} d!w1t=2H
0%#t[usY
/** ?i/73H+;D3
* 获得本页的开始编号,为 (p-1)*num+1 5wy;8a
*/ fHW-Je7mG
publicint getStart(){ %!>k#F^S
return(p - 1) * num + 1; s}Xi2^x
} XlE$.
osI- o~#>
/** Hu[8HzJo
* @return Returns the results. sn2r>m3
*/ e1:u1(".
publicList<E> getResults(){ a"MTQFm'
return results;
Cl%V^xTb
} yIM.j;5:~5
yl[2et
public void setResults(List<E> results){ b;SFI^
this.results = results; YL;SxLY
} ,ZLG7e
}3bQ>whF
public String toString(){ K
lPm=
StringBuilder buff = new StringBuilder U$MWsDn
?<-wHj)
(); Y=PzN3
buff.append("{"); oM/B.U2a
buff.append("count:").append(count); kOo>Iy
buff.append(",p:").append(p); _a?wf!4>P
buff.append(",nump:").append(num); Q1]V|S;)X
buff.append(",results:").append ]Fb8.q5(Y
s$IcDuBu
(results); ~oEXM?M
buff.append("}"); ajf_)G5X P
return buff.toString(); [^cs~
n4
} Ky=(urAd
O@G<B8U,K
} :-W$PIBe
NdaVT5RB
zS&7[:IRs'