Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 ?DVO\Cp
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 4-q7o]%5<
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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 Zl]Zy}p* +
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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 +Ux)m4}j
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分页支持类: N"|^AF
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java代码: 9H*$3
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package com.javaeye.common.util; TX{DZ#
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import java.util.List; =
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publicclass PaginationSupport { `gqBJi
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publicfinalstaticint PAGESIZE = 30; =Mq=\T
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privateint pageSize = PAGESIZE; b:7;zOtF
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privateList items; q`09
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privateint totalCount; pTZPOv#?Q
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privateint[] indexes = newint[0]; u;DF$
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privateint startIndex = 0; MoA2Cp;8X
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public PaginationSupport(List items, int '#t"^E2$
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totalCount){ !.L%kw7z
setPageSize(PAGESIZE); 3P/T`)V
setTotalCount(totalCount); Z!6\KV]
setItems(items); {a_=4a
setStartIndex(0); iAf, :g
} yyk[oH-Q
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public PaginationSupport(List items, int <PW*vo9v
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totalCount, int startIndex){ %xLziF
setPageSize(PAGESIZE); )aquf<u@
setTotalCount(totalCount); .)})8csl.d
setItems(items); JU<<,0
setStartIndex(startIndex); 6luCi$bL
} )rhKWg
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public PaginationSupport(List items, int #x#.@
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totalCount, int pageSize, int startIndex){ 3w{4G<I
setPageSize(pageSize); wias]u|
setTotalCount(totalCount); Sijwh1j*V
setItems(items); ..<(HH2
setStartIndex(startIndex); o'myo.k{
} /c/!13|
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publicList getItems(){ K]@6&H-b|
return items; Ca+d
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} $q.8ve0&^
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publicvoid setItems(List items){ G7%Nwe~Y
this.items = items; nImRU.;P
} ?xK9
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publicint getPageSize(){ ]t0?,q.$7
return pageSize; a<!g*UVL0M
} 3dadeu^{A
W@"M/<r@/
publicvoid setPageSize(int pageSize){ f`WmRx]K
this.pageSize = pageSize; P;hjr;
} 9AB~*;U
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publicint getTotalCount(){ *PL+)2ob
return totalCount; 5?9}^s4
} b)@D*plS&
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publicvoid setTotalCount(int totalCount){ -Rjn<bTIy
if(totalCount > 0){ P|HY=RMa
this.totalCount = totalCount; ?/#HTg)!B
int count = totalCount / e
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pageSize; 'O\K Wj{
if(totalCount % pageSize > 0) RG*Nw6A
count++; !3yR?Xem}
indexes = newint[count]; vGm;en
for(int i = 0; i < count; i++){ ~&B_ Bswf
indexes = pageSize * 4D\_[(P
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i; J|6aa
} MlRgdVX
}else{ qViky=/-
this.totalCount = 0; +#&2*nY
} 8{?Oi'-|0
} / d6mlQS
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publicint[] getIndexes(){ ?r'b
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return indexes; 9QY)<K~a
} >2VB.f
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publicvoid setIndexes(int[] indexes){ 1L l@
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this.indexes = indexes; `]tXQqD
} lfj>]om$
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publicint getStartIndex(){ 7sLs+|<"
return startIndex; Q'Q+mt8u5
} :1.$7Wt
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publicvoid setStartIndex(int startIndex){ 25YJH1x
if(totalCount <= 0) G3?8GTH
this.startIndex = 0; X.T.^}=
elseif(startIndex >= totalCount) :Z=A,G
this.startIndex = indexes Ah)7A|0rT
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[indexes.length - 1]; TSuHY0.cp
elseif(startIndex < 0) 0kC!v,
this.startIndex = 0; >Y{.)QS
else{ =cRJtn
this.startIndex = indexes gCwg ;c-
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[startIndex / pageSize]; Gm>8=
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} i[jAAr$
} im1]:kr7
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publicint getNextIndex(){ < ^J!*>
int nextIndex = getStartIndex() + ?,s{M^sj^
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pageSize; L:B&`,E
if(nextIndex >= totalCount) 2@^8{
return getStartIndex(); =<33(
else L'['7
return nextIndex; YjG0: 9
} b5H[~8mf
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publicint getPreviousIndex(){ <y`yKXzBUV
int previousIndex = getStartIndex() - e@X~F6nP
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pageSize; e#W@ep|n
if(previousIndex < 0) Wxp^*._q3I
return0; \ &_
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else ^s24f?3
return previousIndex; kv5D=0r
} LY^BkH'
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} zHx?-Q&3
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抽象业务类 /?by4v73P
java代码: !0zM@p
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/** X|.X4fs
* Created on 2005-7-12 KXdls(ROP
*/ +/UInAM
package com.javaeye.common.business; zM)o^Fn2
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import java.io.Serializable; Rhr]ML
import java.util.List; }RM?gE
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import org.hibernate.Criteria; Lp{l&-uQ
import org.hibernate.HibernateException; {qh`8
import org.hibernate.Session; `Y+p7*Qr2
import org.hibernate.criterion.DetachedCriteria; [9$>N
import org.hibernate.criterion.Projections; 6%:'2;xM
import C0kwI*)
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org.springframework.orm.hibernate3.HibernateCallback; v'Lckw@G4
import _u.l|yR
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org.springframework.orm.hibernate3.support.HibernateDaoS LR`/pet
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upport; H,zRmK6A%
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import com.javaeye.common.util.PaginationSupport; D4
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public abstract class AbstractManager extends a:@Eg;aN*O
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HibernateDaoSupport { b/<n:*$
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privateboolean cacheQueries = false; i\,#Z!
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privateString queryCacheRegion; K _y;<a]
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publicvoid setCacheQueries(boolean u QCQ$
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cacheQueries){ ;2&(]1X
this.cacheQueries = cacheQueries; Z=wLNm H
} Y$%Ze]~
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publicvoid setQueryCacheRegion(String x+^iEj`gk
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queryCacheRegion){ c 8E&
this.queryCacheRegion = E[e ''
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queryCacheRegion; {fk'g(E8([
} o- GHAQ
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publicvoid save(finalObject entity){ Qs</.PO
getHibernateTemplate().save(entity); "EhA _ =i
} VxaJ[s3PQ&
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publicvoid persist(finalObject entity){ !a4pKN`qLY
getHibernateTemplate().save(entity); $40tAes9
} 9G 9!=J
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publicvoid update(finalObject entity){ c1!h;(&
getHibernateTemplate().update(entity); :8\z 0
} Y+j|T`d
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publicvoid delete(finalObject entity){ ;R|5sCb/m
getHibernateTemplate().delete(entity); ; v>2z!M
} =][[TH
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publicObject load(finalClass entity, YV 2T$#7u
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finalSerializable id){ YzsHec
return getHibernateTemplate().load ,in`JM<o
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(entity, id); W
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} -hyY5!rD
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publicObject get(finalClass entity, lc#su$xR>
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finalSerializable id){ O~l WFaW
return getHibernateTemplate().get jt=mK,%
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(entity, id); l]^uVOX
} E0Ig/
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publicList findAll(finalClass entity){ Q4}2-}|
return getHibernateTemplate().find("from Z^>{bW
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" + entity.getName()); ~UEft
} N'=8Dj
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publicList findByNamedQuery(finalString M')f,5i&$
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namedQuery){ r`HtN{6r
return getHibernateTemplate OpW4@le_r
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().findByNamedQuery(namedQuery); d [6[3B
} _.KKh62CN
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publicList findByNamedQuery(finalString query, T:q!>"5
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finalObject parameter){ Fr`"XH
return getHibernateTemplate !Z3iu
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().findByNamedQuery(query, parameter); eR$qw#%c*
} [>U'P1@ql
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publicList findByNamedQuery(finalString query, LK-2e$1
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finalObject[] parameters){ F\^9=}b_i
return getHibernateTemplate A9`& Wnw?
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().findByNamedQuery(query, parameters); >TK:&V
} Po~{Mpe
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publicList find(finalString query){ ^_0zO$z,
return getHibernateTemplate().find {ZP0%MD
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(query); +*Y/+.4WE$
} dfAnO F"-
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publicList find(finalString query, finalObject C2OBgM+
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parameter){ pN|BtrN{
return getHibernateTemplate().find Lq:
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(query, parameter); mwU|Hh)N]
} lgWEB3f
.
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public PaginationSupport findPageByCriteria (1Q G]1q
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(final DetachedCriteria detachedCriteria){ m?G@#[
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return findPageByCriteria P_6JweN
%xv }
(detachedCriteria, PaginationSupport.PAGESIZE, 0); xvn@zi
} ]@LeyT'cY
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public PaginationSupport findPageByCriteria +||y/}1
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(final DetachedCriteria detachedCriteria, finalint Z'=:Bo{
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startIndex){ m/TjXA8_
return findPageByCriteria CNU,\>J@$
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(detachedCriteria, PaginationSupport.PAGESIZE, &/wd_;d^A
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startIndex); eI99itDQ
} f0Wbc\L[
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public PaginationSupport findPageByCriteria !C]2:+z-MF
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(final DetachedCriteria detachedCriteria, finalint B L^?1x
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pageSize, X"hdCY%
finalint startIndex){ =*2_B~`
return(PaginationSupport) ZH<:g6
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getHibernateTemplate().execute(new HibernateCallback(){ 5ub|r0&M
publicObject doInHibernate m+m2<|%x
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(Session session)throws HibernateException { R V@'$`Q
Criteria criteria = , yd]R4M
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detachedCriteria.getExecutableCriteria(session); ;zF3e&e(
int totalCount = 2?c##Izn
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((Integer) criteria.setProjection(Projections.rowCount `PoFKtVXM
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()).uniqueResult()).intValue(); IJ[r!&PY
criteria.setProjection PAYS~MnV@3
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(null); O-uno{Fd*
List items = :)*+aS"
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criteria.setFirstResult(startIndex).setMaxResults =%=lq0GF0
84U?\f@u
(pageSize).list(); uCB>".'kM
PaginationSupport ps = > a?K![R
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new PaginationSupport(items, totalCount, pageSize, 5|<j Pc
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startIndex); * a ?qV
return ps; {3LAK[C
} -Z(='A
}, true); (,`R >Dk
} _GbwyfA
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public List findAllByCriteria(final {VmJVO]S
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DetachedCriteria detachedCriteria){ 7{JIHY+
return(List) getHibernateTemplate Vu=e|A#
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().execute(new HibernateCallback(){ %iq8dAW%
publicObject doInHibernate |PNPOj0
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(Session session)throws HibernateException { =F<bAZ
Criteria criteria = '#eY4d<i]n
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detachedCriteria.getExecutableCriteria(session); [:BD9V
return criteria.list(); I6e[K(7NY
} Cm"7f!(#
}, true); _c $F?9:
} ^:cc3wt'3[
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public int getCountByCriteria(final xg;I::hE7X
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DetachedCriteria detachedCriteria){ sS{!z@\Lf
Integer count = (Integer) T
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getHibernateTemplate().execute(new HibernateCallback(){ UP .4# 1I
publicObject doInHibernate qokCVI-\
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(Session session)throws HibernateException { =9!|%j
Criteria criteria = ia#8 ^z
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detachedCriteria.getExecutableCriteria(session); f`K[oCfu
return ,^1B"#0{C<
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criteria.setProjection(Projections.rowCount ~?JNI8
5"9'=LV~
()).uniqueResult(); SpC6dkxD\
} Wl0p-h
}, true); 92(P~Sdv
return count.intValue(); @%"r69\
} ;DgQ8"f
} Y(&rlL(sPK
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用户在web层构造查询条件detachedCriteria,和可选的 $1y8X K7r
n{I1ZlEeh
startIndex,调用业务bean的相应findByCriteria方法,返回一个 }2hU7YWt
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PaginationSupport的实例ps。 ]@!3os,CNF
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ps.getItems()得到已分页好的结果集 k&9[}a*
ps.getIndexes()得到分页索引的数组 j6WDh}#
ps.getTotalCount()得到总结果数 Q9Vj8JO"{
ps.getStartIndex()当前分页索引 @|:yK|6O
ps.getNextIndex()下一页索引 pIHpjx
ps.getPreviousIndex()上一页索引 YYhN>d$
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 Q`!^EyRA:^
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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 mu2|%$C;$
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一下代码重构了。 :JU$6
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我把原本我的做法也提供出来供大家讨论吧: M8R/a[ -A
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首先,为了实现分页查询,我封装了一个Page类: D?FmlDTr[
java代码: @KRia{
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/*Created on 2005-4-14*/ Lvrflx*Q
package org.flyware.util.page; y eam-8
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/** >sZ_I?YDs
* @author Joa 55ft,a
* ,$Cr9R&/
*/ 8JXS:J.|v
publicclass Page { x*p'm[Tdtm
TR%8O;
/** imply if the page has previous page */ rk47$36X
privateboolean hasPrePage; T 0qM"
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/** imply if the page has next page */ o;21|[z
privateboolean hasNextPage; \E'z+0
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/** the number of every page */ Tz~a. h@
privateint everyPage; CM6! 1 7
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/** the total page number */ +-T|ov<
privateint totalPage; nvA7eTO6C
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/** the number of current page */ P4LiU2C
privateint currentPage; x |gYxZ
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/** the begin index of the records by the current u08j9)
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query */ I%($,kd}s
privateint beginIndex; mmG]|Cl@
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/** The default constructor */ 7H|0.
public Page(){ \qTp#sF
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} ^/cqE[V~,
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/** construct the page by everyPage `[e0_g\
* @param everyPage cB_9@0r[S
* */ $Ld-lQsL
public Page(int everyPage){ 9g#
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this.everyPage = everyPage; S(^YTb7
} `GlOl-
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/** The whole constructor */ 'T(Q
public Page(boolean hasPrePage, boolean hasNextPage, K4o']{:U
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int everyPage, int totalPage, @=2u;$.
int currentPage, int beginIndex){ I8 [
*
this.hasPrePage = hasPrePage; feH&Ug4?G
this.hasNextPage = hasNextPage; Y+kuj],h
this.everyPage = everyPage; Y^C(<N$
this.totalPage = totalPage; ,7 m33Pv*
this.currentPage = currentPage; v;-0^s/P
this.beginIndex = beginIndex; xA<-'8ST
} %Pl |3 i
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/** Dx=RLiU9
* @return p!)PbSw#
* Returns the beginIndex. Pa#Jwo
*/ LN5BU,4=
publicint getBeginIndex(){ 1<m.Q*
return beginIndex; P[$idRS&
} E{QjmlXQ<
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/** eD3\>Y.z
* @param beginIndex lxbC 7?O
* The beginIndex to set. ^ UhqV"[7k
*/ Z0O0Q =e\Y
publicvoid setBeginIndex(int beginIndex){ I,05'edCQ
this.beginIndex = beginIndex; XD?]+
} b6H7>x
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/** +fKV/tSWi
* @return x^i97dZS^"
* Returns the currentPage. pHye8v4fvi
*/ U%Hcck'
publicint getCurrentPage(){ UUM:*X
return currentPage; @MoCEtt
} ux*G*QZ
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/** =3rf}bl2
* @param currentPage %KN2iNq
* The currentPage to set. 69Z`mR
*/ <lU(9)
L;&
publicvoid setCurrentPage(int currentPage){ jsF5q~F
this.currentPage = currentPage; AAuwE&Gg
} =h?%<2t9<
jq_4x[
/** ar'VoL}
* @return Q,tjODc6n
* Returns the everyPage. N6T
*/ y5D3zqCG
publicint getEveryPage(){ >HzTaXCR[
return everyPage; D vN0h(?
} - K"L6m|
M\Wg|gpy
/** mq(K_
* @param everyPage J-G)mvkv
* The everyPage to set. \l# H#~
*/ ae2I,Qt%
publicvoid setEveryPage(int everyPage){ Y{@foIZ
this.everyPage = everyPage; 1N{ >00
} hOs~/bM
{}gL*2:EW$
/** k^B7M}
* @return _W,?_"[R=
* Returns the hasNextPage. Tc/<b2\g
*/ ?VTP|Z
publicboolean getHasNextPage(){ JE@3 UXg
return hasNextPage; B[f:T%
} }XRfHQk
.Rb1%1bdc
/** 8Bxb~*
* @param hasNextPage CHL5@gg@>y
* The hasNextPage to set. X)c0y3hk
*/ >Il{{{\>
publicvoid setHasNextPage(boolean hasNextPage){ &4M,)Q (
this.hasNextPage = hasNextPage; p}K+4z
} |y?W#xb
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/** \!0~$?_)P
* @return k^s7s{
* Returns the hasPrePage. =^zOM6E1ZF
*/ fq):'E)
publicboolean getHasPrePage(){ /
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return hasPrePage; O"RIY3m
} 1vqc8lC
\@^`
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/** UVsF !0
* @param hasPrePage 4]%MrSjS
* The hasPrePage to set. #,!/Cnqis
*/ w (ev=)7<
publicvoid setHasPrePage(boolean hasPrePage){ >bO}sx1?
this.hasPrePage = hasPrePage; >k~3W> D
} =feVT2*
|~Vq"6`
/** TF,([p*
* @return Returns the totalPage. zWF[cf>'
* E1qf N>0Z
*/ Uo|T6N
publicint getTotalPage(){ DM(c :+K-
return totalPage; Cv]$w(k
} 5j5}c`:
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/** y"w`yl{_
* @param totalPage i| *r/
* The totalPage to set. 0qN+W&H
*/ L@G~9{U>
publicvoid setTotalPage(int totalPage){ [*Vo`WgbD
this.totalPage = totalPage; [R/'hH5
} KU.F4I8}q
ey
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} N6!9QIu~i
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/nNrvMtv
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 'L
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个PageUtil,负责对Page对象进行构造: mX@!O[f%9e
java代码: h09fU5l
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/*Created on 2005-4-14*/ 2zbV9Bhq
package org.flyware.util.page; `& ]H`KNa
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import org.apache.commons.logging.Log; l9F]Lw
import org.apache.commons.logging.LogFactory; <io;d$=}
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/** $Rf)i W;h
* @author Joa H>|*D~RdT
* aHSl_[
*/ m+pFU?<|
publicclass PageUtil { QfI@=Kbg%#
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privatestaticfinal Log logger = LogFactory.getLog ~x g#6%<=
k '-5&Q
(PageUtil.class); &z;1Z
=~'{2gsB
/** ^ <+V[=X
* Use the origin page to create a new page O|Y~^:ny
* @param page *ZV=4[#bT
* @param totalRecords ,qK3
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* @return yMK VF`D*
*/ [>LL
publicstatic Page createPage(Page page, int V})b.\"F
2D'$
totalRecords){ )~ghb"K
return createPage(page.getEveryPage(), ~zL DLr=
}"6
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page.getCurrentPage(), totalRecords); asKAHVT(
} ^(T_rEp
"4/J4'-
/** 1'BC
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* the basic page utils not including exception ?-JW2 E"uT
OmlM9cXm^4
handler 9XmbHS[0V
* @param everyPage yVWt%o/
* @param currentPage Cd|rDa
* @param totalRecords b8**M'k
* @return page #J^ >7v
*/ 8>`8p0I$+
publicstatic Page createPage(int everyPage, int |h& q
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currentPage, int totalRecords){ e[6Me[b
everyPage = getEveryPage(everyPage); Zn:]?%afdO
currentPage = getCurrentPage(currentPage); }=A+W2D
int beginIndex = getBeginIndex(everyPage, vI]V@il
5Gm8U"UR
currentPage); m[ER~]L/C
int totalPage = getTotalPage(everyPage, ]e$n ;tuW
.Hg{$SAC(w
totalRecords); `aSbGMz
boolean hasNextPage = hasNextPage(currentPage, 5t|$Yt[
[8>#b_>
totalPage); 8S5Q{[ !
boolean hasPrePage = hasPrePage(currentPage); KQ0f2?
h+w1 D} *
returnnew Page(hasPrePage, hasNextPage, F^&@[k7WW
everyPage, totalPage, h-fm)1S_
currentPage, iD/+#UTY
\H
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beginIndex); $."Fz
x
} w$j6 !z
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privatestaticint getEveryPage(int everyPage){ ( dh9aR_a
return everyPage == 0 ? 10 : everyPage; "]W,,A-
} tMXNi\Bj
(a"/cH
privatestaticint getCurrentPage(int currentPage){ n`!6EaD
return currentPage == 0 ? 1 : currentPage; _-2;!L#/
} z\YLO%Mm
T8^l}Y
B
privatestaticint getBeginIndex(int everyPage, int js!C`]1
>
w SI0N
currentPage){ }GHCu
return(currentPage - 1) * everyPage; "LH3ZPD
} 2b Fr8FUt-
x4,[5N"}YK
privatestaticint getTotalPage(int everyPage, int )~`UDaj_
7>F [7_
totalRecords){ {XV'C@B
int totalPage = 0; 0Qy L}y2
[zSt+K;
if(totalRecords % everyPage == 0) O\6gw$
totalPage = totalRecords / everyPage; i~)EUF
else ,W;|K 5
totalPage = totalRecords / everyPage + 1 ; G-,0mo
hZWkw{c
return totalPage; "p+JME(
} b1G6'~U -
:B\$7+$v
privatestaticboolean hasPrePage(int currentPage){ 7r2p+LP[
return currentPage == 1 ? false : true; BkY#wJ'
} Mb45UG#2
~Q5]?ZNX
privatestaticboolean hasNextPage(int currentPage, ='@k>Ka+
?{xD{f$
int totalPage){ ?mN!9/DIc
return currentPage == totalPage || totalPage == \tY7Ga%c
D *IeG>%
0 ? false : true; 'I:_}q
} o)$eIu}Wg
`$FB[Z} &
cl |}0Q5
} ?.n1t@sG&
[Dmf.PUe
sbFIKq]
F&B E+b/#
"z=~7g
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。 *SlWA)9Y
;jO+<~YP!
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 .u`A4;;Gw
(f~}5O<
做法如下: Lr(JnS
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 a^ys7UV
EMdU4YnE"
的信息,和一个结果集List: <I 0om(P
java代码: pbIVj3-lY
E>O@Bv
~QUN O~
/*Created on 2005-6-13*/ XQmg^x[,A
package com.adt.bo; g>`D!n::n
.ud&$-[a
import java.util.List; $ f||!g
D9hq$?
import org.flyware.util.page.Page; 91DevizXx
~=<uYv?0s
/** |KO[[4b ?+
* @author Joa _1WA:7$C
*/ _lRIS_^;eE
publicclass Result { 0}|%pmY`
w'7J`n:{]
private Page page; %:Y(x$Qy
c0w1
N]+Ne
private List content; yS3or(K
"$ISun=8
/** =H}x
* The default constructor ,f<J4U:Y
*/ {<#b@=G
public Result(){ +8"P*z,
super(); F(^#_tXP
} Vn\jUEC
2Uu!_n}tNF
/** &qIdT;^=I
* The constructor using fields OI3j!L2f
* a:4!z;2
|
* @param page P^U.VXY}
* @param content }([}A`@
*/ ml!c0<
public Result(Page page, List content){ Prc1U)nfo
this.page = page; NJ;m&Tm,DF
this.content = content; }9!}T~NMs
} WLta{A?
[$:L|V!{
/** xD sKb_
* @return Returns the content. $Zkk14
*/ rhly.f7N=A
publicList getContent(){ {+3g*s/HI
return content; eZ0-O /_i
} iOL/u)
![J_6f}!
/** ]\k&
l
['
* @return Returns the page. x3.,zfWs
*/ IYH4@v/#
public Page getPage(){ t~44ub6GN`
return page; <(V~eo
e
} 6s
~!B{Q
4gWlSm)
/** 4^d).{&X
* @param content A..`?oGj
* The content to set. <aI}+
*/ #hMkajG
public void setContent(List content){ w ykaf
this.content = content; 3preBs#i
} NzeiGj
SZ7; }
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/**
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* @param page n.R"n9v`
* The page to set. 7u5H o`
*/ |Q";a:&$
publicvoid setPage(Page page){ /^bU8E&^M
this.page = page; ]<r.{EJ
} i->G{_gH
} UN:qE oS
OPogH=vf
B?y[ %i
qElPYN*wF
mG0_&'"YIG
2. 编写业务逻辑接口,并实现它(UserManager, >&F:/
;cp||uO
UserManagerImpl) DZEq(>mn
java代码: up0=Y
o@
a0Fq$
VwK7\jV
/*Created on 2005-7-15*/ 0($On`#
package com.adt.service; *~b~y7C
v$5D&Tv
import net.sf.hibernate.HibernateException; &F Yv4J
t)~$p#NS
import org.flyware.util.page.Page; #uICHt3
#YK3Ogb,
import com.adt.bo.Result; 0<fQjXn
8LXK3D}?3
/** @l5GBsLK
* @author Joa $&Z#2
X.
*/ l0g+OMt
publicinterface UserManager { p1mAoVxR
AI9922}*
public Result listUser(Page page)throws }jdmeD:
/~c9'38
HibernateException; giW9b_
RUVrX`u*(
} 3v `@**
N%e^2O)
G-sQL'L[U
$'<$:;4b3
R4$(NNC+/
java代码: \%V !&
!'
HYY+Fv5
Q]VG6x
/*Created on 2005-7-15*/ *Gj`1#Z$
package com.adt.service.impl; (<}?}{YX0
I#7H)^us
import java.util.List; hPCSAo!|
F|o1r
import net.sf.hibernate.HibernateException; ~d ~oC$=TC
0~W6IGE~
import org.flyware.util.page.Page; &!HG.7AY
import org.flyware.util.page.PageUtil; 5~E{bW$
JRAU|gr
import com.adt.bo.Result; 0 wDhX
import com.adt.dao.UserDAO; dX[Xe
import com.adt.exception.ObjectNotFoundException; !X-ThKEq
import com.adt.service.UserManager; Q7/Jyx|
-_]Ceq/
/** u
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* @author Joa ^$RpP+d
*/ EZhk(LE
publicclass UserManagerImpl implements UserManager { =2vZqGO30
P4c}@Mq3
private UserDAO userDAO; Y|W#VyM-
,JPDPI/a
/** 'A1y~x#2B
* @param userDAO The userDAO to set. *e<'|Kq
*/ M*~X pT3
publicvoid setUserDAO(UserDAO userDAO){ &?}h)U#:
this.userDAO = userDAO; L},o;p:
} vy>(?[
f}?pY"yvO
/* (non-Javadoc) 0G+qF96
* @see com.adt.service.UserManager#listUser &b2@+/ F
/1= x8Sb
(org.flyware.util.page.Page) 4FKgp|Y0
*/ AU9:Gu@M/
public Result listUser(Page page)throws )5o6*(Y
kb~ 9/)~g
HibernateException, ObjectNotFoundException { H;Gs0Qi;
int totalRecords = userDAO.getUserCount(); %Rk0sfLvn
if(totalRecords == 0) &[yYgfsp
throw new ObjectNotFoundException th0>u.hJ
ygUX ]*m!
("userNotExist"); 2<V`
page = PageUtil.createPage(page, totalRecords); G,(Xz"`,
List users = userDAO.getUserByPage(page); uF)^mT0D=
returnnew Result(page, users); ?;w\CS^Qu
} Z1(!syg
\fYPz }wt
} >}u#KBedE
tM;+U
ogya~/
zXwdU58
I6S>*V
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 >F/E,U ]
v)*eLX$
询,接下来编写UserDAO的代码: (F:|tiV+
3. UserDAO 和 UserDAOImpl: 1D~B\=LL}
java代码: 7EL0!:P p3
x3jjtjf
.wtYostv
/*Created on 2005-7-15*/ +>%AG&Pc
package com.adt.dao; s:tWEgZk?
160BgFM
import java.util.List; %r:4'$E7|
cZw_^@!
import org.flyware.util.page.Page; UXHtmi|_:
X(C=O?A
import net.sf.hibernate.HibernateException; C{V,=Fo^
1_G+sDw$
/** (IAR-957pN
* @author Joa ;#7:}>}rO
*/ Mo4igP
publicinterface UserDAO extends BaseDAO { yJ8_<A
2o0WS~}5
publicList getUserByName(String name)throws 36 ]?4, .
>V&GL{
HibernateException; )fc+B_
@8SA^u0
publicint getUserCount()throws HibernateException;
8oJp_sw
(i]0IYMXy*
publicList getUserByPage(Page page)throws H*&!$s.
e.;B?0QrV
HibernateException; 1_)Y{3L
JvtbGPz
} Qmj%otSg
?a~#`<
5>h#
hcL
RM!VAFH
<\?dPRw2>
java代码: h{e?Fl
stOD5yi
=o4McV}
/*Created on 2005-7-15*/ q&: t$tSS
package com.adt.dao.impl; C)ebZ3
XC[bEp$
import java.util.List; 8?t}S2n2
V}q=!zz
import org.flyware.util.page.Page; -qDL':
=UZm4=T
import net.sf.hibernate.HibernateException; J-~:W~Qx4N
import net.sf.hibernate.Query; oBWa\N
qD5)AdCGO
import com.adt.dao.UserDAO; bbFzmS1
(.9H1aO46|
/** j 4eq.{$
* @author Joa ]"U/3dL5
*/ @}A3ie'w
public class UserDAOImpl extends BaseDAOHibernateImpl Kl*/{&,P
dqw0ns.2
implements UserDAO { -KiI&Q
.&n;S';"
/* (non-Javadoc) e `IL7$
* @see com.adt.dao.UserDAO#getUserByName s"0Hz"[^=
1tFx
Z#(G
(java.lang.String) ^ V8?6E
*/ {3\{aZ8)
publicList getUserByName(String name)throws Cq<k(TKAX
2<^eVpNJR
HibernateException { Yq-7!
String querySentence = "FROM user in class 1IZTo!xi
<l^#FH
com.adt.po.User WHERE user.name=:name"; rJc=&'{&)N
Query query = getSession().createQuery LKu
,H
3b1%^@,ACy
(querySentence); v^(J+d_>
query.setParameter("name", name); NpF)|Ppb{
return query.list(); =42NQ{%@;
} lxOUV? m^N
@z7$1pl}
/* (non-Javadoc) qJ<Ghd`8v
* @see com.adt.dao.UserDAO#getUserCount() U#F(%b-LC
*/ 8DZ
OPA
publicint getUserCount()throws HibernateException { .7MLgC;
int count = 0; 'Rw*WK
String querySentence = "SELECT count(*) FROM +&8'@v$
,PZ[CX;H@
user in class com.adt.po.User"; <=PYu:]h
Query query = getSession().createQuery #l-/!j
>d5L4&r
(querySentence); aDjYT/`l
count = ((Integer)query.iterate().next E JJW
pDG>9P#mO
()).intValue(); uZ(,7>0
return count; )TyI~5>;
} IyGW>g6_.
k= oCpXq^
/* (non-Javadoc) rd4mAX6@
* @see com.adt.dao.UserDAO#getUserByPage \xexl1_;
gL6.,4q+1
(org.flyware.util.page.Page) x_.}C%
*/ 4W36VtQ@E
publicList getUserByPage(Page page)throws Cc!LJ
gatxvR7H
HibernateException { AWz|HF#-
String querySentence = "FROM user in class HWi: CDgm
1agI/R
com.adt.po.User"; (pkq{: Fs
Query query = getSession().createQuery m15> ^i^W
=U+_;;F=
(querySentence); ]5j1p6;(`
query.setFirstResult(page.getBeginIndex()) C'xWRSDO
.setMaxResults(page.getEveryPage()); @[w.!GW%
return query.list(); L|K^w *\C
} ^?o> (K
]{PJ
} DyPb]Udb:
()%;s2>F
EGJrnz8
^fxS=Qs+
Gjo&~*;
至此,一个完整的分页程序完成。前台的只需要调用 @c^g<
!DNk!]|
userManager.listUser(page)即可得到一个Page对象和结果集对象 /D
~UK"}
_Q6` Wp6m
的综合体,而传入的参数page对象则可以由前台传入,如果用 a&s&6Q|Y
=E4~/F}9/T
webwork,甚至可以直接在配置文件中指定。 pm k;5 d
j`ybz G^
下面给出一个webwork调用示例: rwvCp_pN.
java代码: HC/?o0
#JW~ &;
P_Ni
5s)
/*Created on 2005-6-17*/ &(YNz9L
package com.adt.action.user; 6T ,'Oz
S7WT`2
import java.util.List; =X}s^KbI{
h^=9R6im
import org.apache.commons.logging.Log; 8u4Fag Q,
import org.apache.commons.logging.LogFactory; |&0zAP"\
import org.flyware.util.page.Page; `/L D:R
L#9g ~>~
import com.adt.bo.Result; Q 2nqA1sRk
import com.adt.service.UserService; ?N(opggiD
import com.opensymphony.xwork.Action; D!nx %%q
.[8g6:>
/** e]@R'oM?#`
* @author Joa 2L|)uCb
*/ fs6% M]u
publicclass ListUser implementsAction{ o`<ps$yT
`sPH7^R
privatestaticfinal Log logger = LogFactory.getLog ;Br
#e1~
w-?|6I}T
(ListUser.class); /w2jlu}yt
k~HS_b*]d
private UserService userService; V4qv7
G+zIh}9
private Page page; bA8RoC
J{h?=vK
privateList users; Ft^+P*
BNpc-O~
/* (7J (.EG2e
* (non-Javadoc) Z2^B.r#
* i*2l4
* @see com.opensymphony.xwork.Action#execute() E
(bx/f
*/ Xw |6
#^
publicString execute()throwsException{ 4NxI:d$&*
Result result = userService.listUser(page); p{S#>JTr
page = result.getPage(); n06Jg+
users = result.getContent(); X>kW)c4{b
return SUCCESS; )R@M~d-o
} 9G=HG={
SvN2}]Kh
/** M&~cU{9c
* @return Returns the page. |+r5D4]e
*/ yi@mf$A|
public Page getPage(){ IBSoAL
return page; /Vy,6:$H3
} nMU[S+
!y syb
/** %y_AT2A
* @return Returns the users. )3A%Un#B
*/ ?Y|*EH
publicList getUsers(){ A!.* eIV|
return users; TATH,Sz:x
} #,PB(
V^ 5Z9!
/** #23m_w^L
* @param page tDwj~{a~
* The page to set. C8bv%9
*/ n9x&Ws;
publicvoid setPage(Page page){ ]/y69ou
this.page = page; #uHl
} N_qKIc_R
os~}5QJ
/** vhj^R5=
* @param users ;1[Lwnm
* The users to set. Xsit4Ma
*/ Z5%T pAu[
publicvoid setUsers(List users){ -y5Zc?e
this.users = users; Zk#?.z}
} hDc)\vzr
Q]NGd 0 J
/** >h<bYk "9Q
* @param userService 5*31nMP\
* The userService to set. @E5}v
*/ S+Vsy(
publicvoid setUserService(UserService userService){ Qpaan
this.userService = userService; 8`S6BkfC|
} SP
|R4*KY
} '-k~qQk)6
JD1D(
}2-p=Y:6
!ii'hwFm$
Wy.Xx-3W
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, #v QyECf
jQ[M4)>_k`
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 &$
/}HND
Q0cr^24/
么只需要: 2r~&+0sBP
java代码: sBfPhBT|
L_4ZxsIv
J)xc mK
<?xml version="1.0"?> Md4JaFA(
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork U%,N"]`
>HH49cCo
1.0//EN" "http://www.opensymphony.com/xwork/xwork- `!$I6KxT
|vY0[#E8&
1.0.dtd"> =z$XqT.'
g~AOKHUP
<xwork> z
nc'
4[]/
<package name="user" extends="webwork- 3_]<H<w
O7AW9*<
interceptors"> C'c9AoE5>
Ka"Z,\T
<!-- The default interceptor stack name bqt*d)$
WhR j@y
--> Aey*n=V4#F
<default-interceptor-ref M9/c8zZ
a|x1aN0
name="myDefaultWebStack"/> d:"]*EZ [
ByK!r~>Z1Q
<action name="listUser" ]$>O--
PmGW\E[ni
class="com.adt.action.user.ListUser"> WD^!G;}
<param #iOoi9(
@L-3&~=
name="page.everyPage">10</param> -U?Udmov
<result >*PZ&"}M
ByrK|lVM0
name="success">/user/user_list.jsp</result> 9aR-kcvJIJ
</action> bnz2\C9^
>_Dq )n;%
</package> =Kv*M@
W(oJ{R&m{
</xwork> rSUarfZ<
GIt~"X
/-qSYS(
U9[
&ci
p`)GO.pz
-Cjc~{B>7X
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 +ou
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*Op;].>E
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。 Awo H d7M
I6x
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 JM-spi o
Tl^9!>\Q
mTcop yp
JC~L!)f
(c X;a/BR
我写的一个用于分页的类,用了泛型了,hoho )Jx +R;Z
vps</f!
java代码: lLO|,
H uPw?8w=
4aAuE0
package com.intokr.util; ZqhCGHy
cnQ;6LtFTz
import java.util.List; uT'}_2=:
'~HCYE:5
/** G x;U 3iV
* 用于分页的类<br> >+iJ(jqq
* 可以用于传递查询的结果也可以用于传送查询的参数<br> B?
$9M9
* [Bn C_^[W
* @version 0.01 '?Mt*%J@=$
* @author cheng "@1e0`n
Q
*/ |H`}w2U[j
public class Paginator<E> { *=Ko"v
}
privateint count = 0; // 总记录数 '->%b
privateint p = 1; // 页编号 :.863_/
privateint num = 20; // 每页的记录数 EZy:_xjZ
privateList<E> results = null; // 结果 F)ak5
|JZ3aS
/** zn| S3c
* 结果总数 :6k8\{^9"D
*/ m0}Pq{g
publicint getCount(){ J9!}8uD
return count; S
VCTiG8t
} \LYB% K}
{}r#s>
publicvoid setCount(int count){ kD&%
7Vz
this.count = count; CH!>RRF
} h<)YZ[;x
[$PW {d8|
/** b-Q*!Ut
* 本结果所在的页码,从1开始 tPv3nh
* ObK-<kGcB
* @return Returns the pageNo. ?T]` X
*/ L5(7;
publicint getP(){ Y nD_:ZK
return p; %sd1`1In
} ,8=`Y9#
1k=w 9
/** up(6/-/.7
* if(p<=0) p=1 %2H0JXKa,
* xEW>7}+\
* @param p &hTe-Es
*/ Z7\}x"hk
publicvoid setP(int p){ $KSdNFtM)A
if(p <= 0) DrAp&A|WV|
p = 1; qDG{hvl[1r
this.p = p; <1t.f}}uX
} 1 u[a713O
Uq}F rK}
/** 4Ss4jUj
* 每页记录数量 7D5[
L
*/ !p:kEIZ)y
publicint getNum(){ v'0WE
return num; Ijg//=
} Ly\ `
s5`CV$bz
/** BM~>=emc
* if(num<1) num=1 XZh1/b^DMN
*/ V-1H(wRu
publicvoid setNum(int num){ fGZZ['E
if(num < 1) Z-md$=+}w
num = 1; "3&bh>#qY
this.num = num; D)O2=aQ;]
} L<7KmN4VX
ec8iZ8h8
/** [6ycs[{!
* 获得总页数 3]46qk'
*/ G+_Q7-o&d6
publicint getPageNum(){ 1<9=J`(H
return(count - 1) / num + 1; g-C)y
06
} [Sj _=
/JqNiqvh
/** a^#\"c
* 获得本页的开始编号,为 (p-1)*num+1 o4.?m6d
*/ S17iYjy#8T
publicint getStart(){ h^B~Fv>~
return(p - 1) * num + 1; /h]#}y j
} M~?2g.o'D
yQ [n7du
/** > w-fsL
* @return Returns the results. G?,b51"
*/ -X]?ql*%`
publicList<E> getResults(){ >s%&t[r6
return results; za,JCI
} v1R t$[
t}Q
PPp y
public void setResults(List<E> results){ }J ^+66{
this.results = results; ^~7/hm:
} srGF=1_
_{C
=d3
public String toString(){ VF bso3q<j
StringBuilder buff = new StringBuilder V[#$Sz[G
IaHu$` v
(); Z,"f2UJ
buff.append("{"); 4!U)a
buff.append("count:").append(count); Zl\$9Q_
buff.append(",p:").append(p); xf7_|l
buff.append(",nump:").append(num); xTGdh
buff.append(",results:").append 7Eo;TNbb
PR2;+i3
(results); lD-HQd
buff.append("}"); VprrklZ
return buff.toString(); /J5)_>R:
} =J GL~t?
S\S31pYT
} dcH@$D@~S
QFg{.F?3q>
?ZAynZF|#