Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 U7iuY~L
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 VR5fqf|*
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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 2+o|A
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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 nkDy!"K
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分页支持类: RthT\%R
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java代码: Oco YV J
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package com.javaeye.common.util; wsU V;S*X%
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import java.util.List; q2rUbU_A(
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publicclass PaginationSupport { nqVZqX@oE
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publicfinalstaticint PAGESIZE = 30; C1EtoOv K
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privateint pageSize = PAGESIZE; q my%J
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privateList items; -62'}%?A<C
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privateint totalCount; J?UQJ&!@O
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privateint[] indexes = newint[0]; J[~5U~F
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privateint startIndex = 0; bI.t<;
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public PaginationSupport(List items, int k67a'pmyJ
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totalCount){ 1?*
setPageSize(PAGESIZE); !\8 ;d8
setTotalCount(totalCount); K_?W\Yg
setItems(items); %ek'~
setStartIndex(0); h:zK(;
} ^.k
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public PaginationSupport(List items, int ~_IHaw$hg
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totalCount, int startIndex){ vx_o(wof
setPageSize(PAGESIZE); 'I;!pUfVp
setTotalCount(totalCount); ]lw|pvtd
setItems(items); KDl_?9E5
setStartIndex(startIndex); 0;4t&v7
} m-^8W[r+_
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public PaginationSupport(List items, int r78TE@d
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totalCount, int pageSize, int startIndex){ #P]#9Ty:
setPageSize(pageSize); `n$5+a+
setTotalCount(totalCount); pV4Whq$
setItems(items); &Ysosy*
setStartIndex(startIndex); \U|ZR
} kJWN.
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publicList getItems(){ '*\|;l#1
return items; *@d&5
} Y"OG@1V;8
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publicvoid setItems(List items){ PJ cwH6m
this.items = items; Y&/]O$<
} Or
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publicint getPageSize(){ Q{B}ef
return pageSize; r5!/[_l
} aW!@f[%~F
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publicvoid setPageSize(int pageSize){ gJ2>(k03y
this.pageSize = pageSize; ,t\* ZTt$
} [s&$l G!
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publicint getTotalCount(){ 5|jw^s7
return totalCount; S[7WW$lF
} L#vI=GpL,r
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publicvoid setTotalCount(int totalCount){ dnj}AVfQx
if(totalCount > 0){ rXA*NeA3v
this.totalCount = totalCount; Nbp!teH6
int count = totalCount / r#xg#u oj
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pageSize; >@"Oe
if(totalCount % pageSize > 0) >Wz;ySEz
count++; J/}:x;Y
indexes = newint[count]; UKM2AZ0lb
for(int i = 0; i < count; i++){ d>{nQF;c
indexes = pageSize * V*W;OiE_3
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} }<dRj
}else{ .l@xsJn
this.totalCount = 0; Yot?=T};3{
} B, 9w0
} _cu:aktf2
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publicint[] getIndexes(){ Zfyo-Wk
return indexes; `3:.??7N
} g&`pgmUX
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publicvoid setIndexes(int[] indexes){ J9=m]R8T
this.indexes = indexes; #vry0i
} !%c'$f/
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publicint getStartIndex(){ -=(!g&0
return startIndex; !H ~<
} $ibuWb"a
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publicvoid setStartIndex(int startIndex){ s&NX@
if(totalCount <= 0) O)"gS!,
this.startIndex = 0; SCz(5[MZJ
elseif(startIndex >= totalCount) 8H_l:Z [:i
this.startIndex = indexes ;6!Pwb;hY
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[indexes.length - 1]; i@4~.iZ8
elseif(startIndex < 0) . Z%{'CC
this.startIndex = 0; g>J<%z,}2
else{ 1Uqu>'
this.startIndex = indexes 4fKC 6UR
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[startIndex / pageSize]; bP^Je&nS*
} 65Cg]Dt71
} T8HF|%I
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publicint getNextIndex(){ CXC`sPY
int nextIndex = getStartIndex() + L>YU,I\o
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pageSize; ]GRWnif
if(nextIndex >= totalCount) %wSj%>&-R
return getStartIndex(); q5#J~n8Wr
else K=,F#kn
return nextIndex; c.j$9=XLBG
} R[;zX(y
>>5NX"{
publicint getPreviousIndex(){ =|YxDas
int previousIndex = getStartIndex() - ]X^rU`":
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pageSize; QI3Nc8t_2
if(previousIndex < 0) W]5USFan
return0; E~_]Lfs)
else 8A+SjJ4$
return previousIndex; YWxc-fPZ
} :at$HCaK
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} r}jGUe}d
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抽象业务类 <0PT"ij
java代码: &Y^WP?HS
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/** :=[XW?L%x
* Created on 2005-7-12 j<)9dEM'
*/ <,>P 0tY}
package com.javaeye.common.business; :P(K2q3
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import java.io.Serializable; 14"J d\M8
import java.util.List; /*c\qXA5
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import org.hibernate.Criteria; *Otg*,\
import org.hibernate.HibernateException; _X'"w|0
import org.hibernate.Session; \R3H+W
import org.hibernate.criterion.DetachedCriteria; xQp|;oW;z
import org.hibernate.criterion.Projections; ?2g`8[">
import S*,rGCt'T
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org.springframework.orm.hibernate3.HibernateCallback; q.()z(M7
import R%c SJ8O#
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org.springframework.orm.hibernate3.support.HibernateDaoS ubmrlH\d
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upport; NoJ`6MB
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import com.javaeye.common.util.PaginationSupport; u@4V7;L
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public abstract class AbstractManager extends d`(@_czdF
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HibernateDaoSupport { kn/Ao}J74z
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privateboolean cacheQueries = false; \2vg{
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privateString queryCacheRegion; l#}.^71+
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publicvoid setCacheQueries(boolean 8zBWIi
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cacheQueries){ NS C/@._
this.cacheQueries = cacheQueries; c={Ft*N
} ]/cd;u
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publicvoid setQueryCacheRegion(String &5t :H 8b
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queryCacheRegion){ -@&1`@):{
this.queryCacheRegion = [\Qr. 2
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queryCacheRegion; !rhk
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} ~np,_yI
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publicvoid save(finalObject entity){ /VHi>
getHibernateTemplate().save(entity); MEiRj]t
} jKIc09H|
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publicvoid persist(finalObject entity){ tD$lNh^
getHibernateTemplate().save(entity); xdy^^3"
} m?[5J)eR
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publicvoid update(finalObject entity){ Rb}KZ+o"Z
getHibernateTemplate().update(entity); 6*@yE
}
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publicvoid delete(finalObject entity){ }vt%R.u
getHibernateTemplate().delete(entity); $WW)bP
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} ~2_lp^Y
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publicObject load(finalClass entity, o{-<L
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finalSerializable id){ [{&jr]w`|
return getHibernateTemplate().load ~9$X3.+
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(entity, id); EqM;LgE=
} T,JA#Rk|1N
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publicObject get(finalClass entity, ,R wfp=*E
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finalSerializable id){ 7]22"mc
return getHibernateTemplate().get %3Bpn=k>
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(entity, id); PoD^`()FR{
} CHaE;olo
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publicList findAll(finalClass entity){ ^i_Iqph=
return getHibernateTemplate().find("from "<l<&
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" + entity.getName()); .`C
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} Nw](".
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publicList findByNamedQuery(finalString 5 d ;|=K
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namedQuery){ uMFV%+I
return getHibernateTemplate KAb(NZK
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().findByNamedQuery(namedQuery); %cW;}Y[?P
} if~rp-\P
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publicList findByNamedQuery(finalString query, 93w~.p
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finalObject parameter){ (@]tG?I=
return getHibernateTemplate <d@pmh
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().findByNamedQuery(query, parameter); #/WAzYt{
} Vm!i
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publicList findByNamedQuery(finalString query, .C5@QKU
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finalObject[] parameters){ $!`L"szqD*
return getHibernateTemplate g@E&uyM
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().findByNamedQuery(query, parameters); }[,3yfiX
} (2%>jg0M
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publicList find(finalString query){ ?L`ZKRD
return getHibernateTemplate().find C
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(query); eU~?p|Np
} d;g-3Pf
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publicList find(finalString query, finalObject 9Dq.lr^
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parameter){ %O /d4
return getHibernateTemplate().find RHXvee55
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(query, parameter); Ma_=-cD
} ]Wy.R6
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public PaginationSupport findPageByCriteria L?.7\a@
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(final DetachedCriteria detachedCriteria){ Y^5"qd|`
return findPageByCriteria O*4gV }:G
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); Mz}i[|U\
} 4ac1m,Jlt
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public PaginationSupport findPageByCriteria S[.5n]
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(final DetachedCriteria detachedCriteria, finalint ^#7viZ*
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startIndex){ xBt<Yt"
return findPageByCriteria b_l.QKk
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(detachedCriteria, PaginationSupport.PAGESIZE, uc\.oG;~q
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startIndex); 2|
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} i&1U4q
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public PaginationSupport findPageByCriteria ?.~]mvOR
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(final DetachedCriteria detachedCriteria, finalint -P*xyI
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pageSize, 0tSA|->(
finalint startIndex){ RAdvIIQp:
return(PaginationSupport) 6l<1A$BQ
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getHibernateTemplate().execute(new HibernateCallback(){ fls#LcI9>6
publicObject doInHibernate C*$|#.l
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(Session session)throws HibernateException { 4 ;^g MI9
Criteria criteria = F"Uh/EO<
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detachedCriteria.getExecutableCriteria(session); BjwMb&a;
int totalCount = l~ CZW*/
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((Integer) criteria.setProjection(Projections.rowCount { _-wG3f|
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()).uniqueResult()).intValue(); z( *]'Y
criteria.setProjection KxGKA
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(null); w<v1N
List items = C0P*D,
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criteria.setFirstResult(startIndex).setMaxResults 2\DTJ`Y,
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(pageSize).list(); 4,gol?a
PaginationSupport ps = `Fz\wPd
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new PaginationSupport(items, totalCount, pageSize, &zO3qt6
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startIndex); 2%`^(\y
return ps; mu 2
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} U LV)0SB
}, true); mx:J>SPA8
} ,LoMt ]H
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public List findAllByCriteria(final KuIBYaK,
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DetachedCriteria detachedCriteria){ =X)Q7u".7
return(List) getHibernateTemplate c*Eok?O
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().execute(new HibernateCallback(){ %~][?Y ><
publicObject doInHibernate pQk=x T
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(Session session)throws HibernateException { ?SB[lbU
Criteria criteria = Uzan7A
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detachedCriteria.getExecutableCriteria(session); c-[Q,c
return criteria.list(); b24NL'jm
} %'RI3gy
}, true); PN1(j|
} -}=@
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public int getCountByCriteria(final Qw3a"k-
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DetachedCriteria detachedCriteria){ 3I'M6WA
Integer count = (Integer) 54`bE$:+
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getHibernateTemplate().execute(new HibernateCallback(){ ?l)}E
publicObject doInHibernate +O;OSZ
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(Session session)throws HibernateException { l-DGy# h+z
Criteria criteria =
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detachedCriteria.getExecutableCriteria(session); QVnO
return g_rA_~dh
s|{^ }4{
criteria.setProjection(Projections.rowCount D)H?=G
}V1DyLg:
()).uniqueResult(); F'V+2,.
} sDzD
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}, true); O0K@M
return count.intValue(); LU-#=1Q
} }vXA`)Ns
} 0Zc*YdH
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用户在web层构造查询条件detachedCriteria,和可选的 /o<}]]YBF
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 w*&n(zJF>
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PaginationSupport的实例ps。 +WV_`Rx#
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ps.getItems()得到已分页好的结果集 3/A[LL|
ps.getIndexes()得到分页索引的数组 T!=20 !I
ps.getTotalCount()得到总结果数 >,]
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ps.getStartIndex()当前分页索引 %#S "~)
ps.getNextIndex()下一页索引 DWm;&RPJ
ps.getPreviousIndex()上一页索引 j{7ilo(i
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 bgzT3KZ
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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 NU)`js
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一下代码重构了。 JucxhjV#,
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我把原本我的做法也提供出来供大家讨论吧: :ET3&J
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首先,为了实现分页查询,我封装了一个Page类: y3@x*_K8
java代码: z2s|.M]&-D
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/*Created on 2005-4-14*/ RBK>Lws6
package org.flyware.util.page; G0 nH Z6
jy__Y=1}
/** FSYjp{z5
* @author Joa ?{.b9`
* gGiV1jN_
*/
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publicclass Page { Xb+if
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/** imply if the page has previous page */ a`@<Z sR
privateboolean hasPrePage; s:jL/%+COZ
vVAZSR#
/** imply if the page has next page */ m)[wZP*e
privateboolean hasNextPage; 5rHnU<H@y
&h4Z|h[01
/** the number of every page */ ^?^|Y?f2P?
privateint everyPage; c@o/Cv
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/** the total page number */ RP@idz
privateint totalPage; xU\:Vid+A
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/** the number of current page */ 4KSP81}/\
privateint currentPage; 1:{O RX[;
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/** the begin index of the records by the current 4Tzu"y
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query */ J*lYH]s
privateint beginIndex; 'xrbg]b%
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/** The default constructor */ l& ^B
public Page(){ X8l1xD
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} K[|P6J
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/** construct the page by everyPage dBq,O%$oq
* @param everyPage 8H`l"
* */ )J6b:W
public Page(int everyPage){ Jp*AIj
this.everyPage = everyPage; }?q nwx.
} <$3nD b-
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/** The whole constructor */ zUgkY`]:BJ
public Page(boolean hasPrePage, boolean hasNextPage, BiLreZ~"
{e
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int everyPage, int totalPage, <sFf'W_3{
int currentPage, int beginIndex){ xY'YbHFz
this.hasPrePage = hasPrePage; 6=lQT
9u{
this.hasNextPage = hasNextPage; ?
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this.everyPage = everyPage; <@j
this.totalPage = totalPage; np>!lF:
this.currentPage = currentPage; __n"DLW
this.beginIndex = beginIndex; HY| SLk/E
} ?#c@Ag%
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/** gV44PI6h
* @return i@j ?<
* Returns the beginIndex. )ZU#19vr7
*/ >)Z2bCe
publicint getBeginIndex(){ 1'pQ,
return beginIndex; K:50?r_-6
} #YVDOR{z
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/** >Ez}r(QQ^
* @param beginIndex 0 S8{VZpy
* The beginIndex to set. ^a 5~FI:
*/ .7Bav5 ;
publicvoid setBeginIndex(int beginIndex){ %a^!~qV
this.beginIndex = beginIndex; 2m}]z.w#
} W&[9x%Ba
Y k6WSurw
/** d}CMX$1
* @return {73DnC~N
* Returns the currentPage. uHh2>Px
*/ 9.}3RAB(cv
publicint getCurrentPage(){ m,fr?d/;
return currentPage; fb=vO U
} 4[j) $!l`
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/** Y(mwJud|
* @param currentPage 2uB26SEIl
* The currentPage to set. U.)eJ1a
*/ 7cQw?C
publicvoid setCurrentPage(int currentPage){ !}m8]&
this.currentPage = currentPage; Gwk@X/q
} JsdEA
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/** :9>nY
* @return xBd%e-r
* Returns the everyPage. ,
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*/ O$ \N]#
publicint getEveryPage(){ VJPP HJ[-
return everyPage; of<OOh%3
} S+ x[1#r
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/** *V+fRN4 W
* @param everyPage w%"q=V
* The everyPage to set. #7) 6X:/O
*/ /;J;,G`?
publicvoid setEveryPage(int everyPage){ iWsIc\!+,
this.everyPage = everyPage; q\G@Nn^
} >m46tfoM
oWT0WS
/** ng\S%nA&J
* @return Il[WXt<S
* Returns the hasNextPage. ZH*?~ #
*/ B$n\m854
publicboolean getHasNextPage(){ Ro69woU
return hasNextPage; ZGBcy}U(k
} LPClE5
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/** EJsb{$u
* @param hasNextPage pQJZE7S
* The hasNextPage to set. {w(N9Va,(
*/
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publicvoid setHasNextPage(boolean hasNextPage){ e!yt<[ph
this.hasNextPage = hasNextPage; a7R7Ks|q
} aeIR}'H|
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/** ?6gI8K6X
* @return W\.(~-(So
* Returns the hasPrePage. B:SRHd{*Wu
*/ )XWL'':bF
publicboolean getHasPrePage(){ scmbDaOn
return hasPrePage; #';r 0?|
} G5Nub9_*X
)ALcmC?!#
/** \hVFK6
* @param hasPrePage qIl@,8T
* The hasPrePage to set. +VDB\n
*/ NUseYU``
publicvoid setHasPrePage(boolean hasPrePage){ d p].FS
this.hasPrePage = hasPrePage; GOjri
} 5;+Bl@zGu
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/** uQ}kq7gd
* @return Returns the totalPage. YR>x h2< 9
* BR*U9K|W
*/ Gvw el!6
publicint getTotalPage(){ Mh\c +1MFs
return totalPage; e):
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} kE1u-EA
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/** vKxwv
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* @param totalPage :v+39
* The totalPage to set. V*)gJg
*/ MC3{LVNK
publicvoid setTotalPage(int totalPage){ >A6lX)
this.totalPage = totalPage; d+kIof,
} UCFef,VW
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} >:.Bn 8-
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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 DLVf7/=3~
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个PageUtil,负责对Page对象进行构造: Wh7$')@
java代码: -LF^u;s8&S
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/*Created on 2005-4-14*/ "&An9H'
package org.flyware.util.page; XWk^$ "
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import org.apache.commons.logging.Log; V`G]4}
import org.apache.commons.logging.LogFactory; ?>e-6*.
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/** tjGQ0-Lo
* @author Joa 3AWg 43L7
* P*_Q 8I)Y
*/ 9R!.U\sq
publicclass PageUtil { Av{1~%hU
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privatestaticfinal Log logger = LogFactory.getLog `6'fX[j5
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(PageUtil.class); [H!V
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/** 4Xlq
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* Use the origin page to create a new page ~ u jY+{
* @param page Bc$t`PI
* @param totalRecords 26j ; RV
* @return Z{|wjZb(
*/ 5G|(od3
publicstatic Page createPage(Page page, int Fq:BRgCE
074)(X&:x
totalRecords){ V|Smk;G
return createPage(page.getEveryPage(), |-bAzt
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page.getCurrentPage(), totalRecords); du Pzt
} B\`4TU}kE
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/** j8P=8w{
* the basic page utils not including exception z^bv)u
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handler C0J/FFBQ ^
* @param everyPage pkQEry&Z
* @param currentPage X)P9f N~7
* @param totalRecords Qt`}$]
* @return page edD1 9A
*/ gm'8,ZL
publicstatic Page createPage(int everyPage, int [_q3 02
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currentPage, int totalRecords){ llN#4D9s
everyPage = getEveryPage(everyPage); `ZhDoLpH<
currentPage = getCurrentPage(currentPage); K?`Fpg(
int beginIndex = getBeginIndex(everyPage, Fu].%`*xJ
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currentPage); 1ayL*tr
int totalPage = getTotalPage(everyPage, /x\{cHAt8J
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totalRecords); cgY+xd@
boolean hasNextPage = hasNextPage(currentPage, A0JlQE&U
?>
)(;Ir9
totalPage); G*` Y~SJp
boolean hasPrePage = hasPrePage(currentPage); \\}tD@V"
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returnnew Page(hasPrePage, hasNextPage, 4E:kDl* @
everyPage, totalPage, {{N*/E^
currentPage, ,%Sf,h?"^
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beginIndex); Ts)ox}rYVm
} J7a_a>Y
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privatestaticint getEveryPage(int everyPage){ nz+k ,
return everyPage == 0 ? 10 : everyPage; *e/8uFX
} @
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/N=;3yWF
privatestaticint getCurrentPage(int currentPage){ s&.VU|=VQ@
return currentPage == 0 ? 1 : currentPage; -0P(lkylf
} KcPI,.4{
|
6/ # H*
privatestaticint getBeginIndex(int everyPage, int Ga,+
`
b$u w
currentPage){ 0*y|k1
return(currentPage - 1) * everyPage; &-R(u}m-F
} RZ+SOZs7H
0Tp,b (;n
privatestaticint getTotalPage(int everyPage, int (?y (0%q
jq_E{Dq1
totalRecords){ i`st'\I
int totalPage = 0; ,2>nr goM
K."%PdC
if(totalRecords % everyPage == 0) w%' 8bH!
totalPage = totalRecords / everyPage; vXI2u;=y
else YZ\a#s,0
totalPage = totalRecords / everyPage + 1 ; Rlyx&C8
3OZu v};k
return totalPage; d,y%:F 4
} vr2cDk{
jXH?os%
privatestaticboolean hasPrePage(int currentPage){ f?Am)
return currentPage == 1 ? false : true; G_1`NyI
} :@oy5zib
F4X0DRC,G
privatestaticboolean hasNextPage(int currentPage, D #Ku5~j
a@?2T,$
int totalPage){ ?yNg5z
return currentPage == totalPage || totalPage == gR#lRA/
Bj1{=Pvl
0 ? false : true; kklM"Av
} I7C*P~32{n
W|,Y*l
;l$F<CzJay
} f#>ubmuI^
{];8jdg/?
,GVD.whUl
\ )'`F;
P
-ufO,tJRLL
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 &i{>Li
aMq|xHZ
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 +=o?&
6 {j}Z*)m
做法如下: r@)_>(
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 :=cZ,?PQp1
V'Z Z4og
的信息,和一个结果集List: j~;kh_
java代码: B\mRHV!
mh7JPbX|
*wu:fb2[(
/*Created on 2005-6-13*/ hT
DFIYV
package com.adt.bo; !kG 2$/lR
QKVFH:"3
import java.util.List; T=~D>2C
^$VH~i&
import org.flyware.util.page.Page; Ro:DAxi@L
s%OPoRE
/** .KeZZLH
* @author Joa x(r~<a[
*/ 9o<5Z=
publicclass Result {
p~bx
fFiFS\''V
private Page page; tA{B~>
j8[RDiJ
private List content; o1^Rx5
1Vi3/JM@
/** +5xVgIk#
* The default constructor QoBM2QYO
*/ \:Vm7Zg
public Result(){ >"?jW@|g
super(); hwj:$mR
}
)/mBq#ZS
'OjsV$_
/** WMk;-,S!)
* The constructor using fields 8{)j"rghah
* v3I-i|L<)
* @param page 29tih{xx
* @param content 4Uzx2
*/ *w,C5 f
public Result(Page page, List content){ q>5K:5
this.page = page; jBLLx{
this.content = content; 7Bs:u
} ~M Mv+d88
=6H
/** 5SQqE@g%
* @return Returns the content. n~Qo@%Jr
*/ < ?{ic2j#
publicList getContent(){ [L`w nP
return content; @0[#XA_>
} IDn$w^"
RTQtXv6mD
/** u?%FD~l:uU
* @return Returns the page. 9ymx;
*/ @CNe)&U
public Page getPage(){ ZgI ?#e
return page; V*j1[d
} <;P40jDL
Rn9e#_ Az
/** ~pWV[oUD
* @param content >j6"\1E+Dz
* The content to set. P+<4w
*/ 6z2W N|78
public void setContent(List content){ +"GBuNh
this.content = content; 5=hMTztf!!
} ~v|NC([(
p:?h)'bA<
/** h\lyt(.s
* @param page ,*m{Q
* The page to set. 5iZx
-M
*/ &1Cif$Y4w
publicvoid setPage(Page page){ v7b+
this.page = page; !$pnE:K
} ]Il}ymkIZ
} kHz?vVE/l
AOv>O52F/Q
)Nt'Z*K*
pv"QgH
#7Jvk_r9Y
2. 编写业务逻辑接口,并实现它(UserManager, vWVQ8S.
W4&Itj
UserManagerImpl) S5/p3;O\c
java代码: Y.KJP ?
AYsiaSTRqW
l&{+3 aC:
/*Created on 2005-7-15*/ Ti>2N
package com.adt.service; <Gj]XAoe%
fRK=y+gl@
import net.sf.hibernate.HibernateException; (Qd@Q,@(s
hka`STK{
import org.flyware.util.page.Page; v9MliD'
[PH56f
import com.adt.bo.Result; =|V [^#V
FV\$M6
_
/** F5
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* @author Joa m2v'zJd}g
*/
(V<pz2\
publicinterface UserManager { of/'
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2[I[I*"_d
public Result listUser(Page page)throws 9t+:L(*pK
$g '4'
HibernateException; 9)J)r\
nVoP:FHH
} R_gON*9
JlE b
IPk"{T3
hx
hs>eY
:Fdk`aC
java代码: ofuQ`g1hb
MZS/o3
N{?Qkkgx
/*Created on 2005-7-15*/ kk ZMoK
package com.adt.service.impl; V PI_pK
7'RU\0QG
import java.util.List; ]~7xq)28
t'* 2)U
import net.sf.hibernate.HibernateException; # 66vkf*
K-n]m#U4o
import org.flyware.util.page.Page; 3yu,qb'"&
import org.flyware.util.page.PageUtil; [='<K
Nrzg>WQa
import com.adt.bo.Result; E[M.q;rM
import com.adt.dao.UserDAO; ?<~P)aVVj
import com.adt.exception.ObjectNotFoundException; $o^N_`l
import com.adt.service.UserManager; Z[9f8/6<b
m`#UV-$J
/** oD_#oX5\
* @author Joa -9yWf8;
*/ 28O 3N;a
publicclass UserManagerImpl implements UserManager { T^H`$;\
_SqUPTb"u
private UserDAO userDAO; m-'+)lB
6B@{X^6y
/** +?uZ~VSl
* @param userDAO The userDAO to set. ~}ba2dU8
*/ ^i6`w_ /
publicvoid setUserDAO(UserDAO userDAO){ q@}tv=}
this.userDAO = userDAO; L lVE5f?
} l%v2O'h
jo ~p#l.'
/* (non-Javadoc) _}Ec[c
* @see com.adt.service.UserManager#listUser &u0on)E
R![1\Yv&
(org.flyware.util.page.Page) !\|L(Paf
*/ hA387?
public Result listUser(Page page)throws nj7\vIR7
q[TW
HibernateException, ObjectNotFoundException { #&&
int totalRecords = userDAO.getUserCount(); O*PJr[Zou
if(totalRecords == 0) ThYHVJ[;
throw new ObjectNotFoundException =R0#WMf$@
"U
iv[8B
("userNotExist"); C%;J9(r
page = PageUtil.createPage(page, totalRecords); z>O =. Ku6
List users = userDAO.getUserByPage(page); U[c^xz&
returnnew Result(page, users);
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} ZvkBF9d
]L9$JTGF`w
} R;F z"J
)r6d3-p1
H1a<&7
Rx.dM_S
|gM@}!DL
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 ]VHO'z\m
.{66q#.
询,接下来编写UserDAO的代码: n]snD1?KX
3. UserDAO 和 UserDAOImpl: 8?&!@3n
java代码: N.|uPq$R
ZqJyuTPv
{{Z3M>Q
/*Created on 2005-7-15*/ dS~#Lzm
package com.adt.dao; o;7_*=i
2JLXDkZ
import java.util.List; nVv=smVOt
KmaMS(A(3
import org.flyware.util.page.Page; _kJW/3eE
5Jm%*Wb
import net.sf.hibernate.HibernateException; |9fGn@-
nfA#d-
/** LLW
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* @author Joa -%>.Z1uj
*/ ql%]t~HR0
publicinterface UserDAO extends BaseDAO { 'A#F< x
/|aD,JVN"
publicList getUserByName(String name)throws %$}*y
QOKE9R#Y
HibernateException; _.K<#S
i2m+s;
publicint getUserCount()throws HibernateException; xGo,x+U*
<ly.l]g
publicList getUserByPage(Page page)throws [E4#|w
qn#f:xltu
HibernateException; l]KxUkA+
E//*bmww
} JqtOoR
orhzeOi\
0oo_m6ie&
,irc=0M(
4"eeEs h
java代码: hA+;eXy/
M1I4Ot
tDtqTB}
/*Created on 2005-7-15*/ Qm4cuV-0{
package com.adt.dao.impl; 5Zl7crA [
}DQ[C&
import java.util.List; 9`!#5i)VU8
/Q'O]h0a
import org.flyware.util.page.Page; n"<'F4r
X
[;n149o
import net.sf.hibernate.HibernateException; Tvw(Sq};
import net.sf.hibernate.Query; y2Vc[o(NP
yppXecFJ
import com.adt.dao.UserDAO; 2>.>q9J(
l#a*w
/** soqnr"
1
* @author Joa wD SSgk
*/ i~tps
public class UserDAOImpl extends BaseDAOHibernateImpl ]#dZLm_
q,]57s
implements UserDAO { MT<3OKo?:
0p=
/* (non-Javadoc) Z$S0X$q}
* @see com.adt.dao.UserDAO#getUserByName \ $
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.&/A!3pW
(java.lang.String) xt8@l
[Z
*/ Pcr;+'q
publicList getUserByName(String name)throws <9`/Y"\ p
RMa#z [{0
HibernateException { vr$z6m ^
String querySentence = "FROM user in class $'b b)@_
M B,Z4 ^
com.adt.po.User WHERE user.name=:name"; dfs1BV'
Query query = getSession().createQuery Dm`gzGl
J=ot&%
(querySentence); fw0Z- 9*
query.setParameter("name", name); N~B'gJJDx
return query.list(); N}q*(r!q<
} = %wBC;
cX5t x]
/* (non-Javadoc) E /V`NqC
* @see com.adt.dao.UserDAO#getUserCount() #uuNH(
*/ #}xPOz7:
publicint getUserCount()throws HibernateException { rH[Eh8j,
int count = 0; A{Q~@1
String querySentence = "SELECT count(*) FROM #b{;)C fL
g")pvK[e
user in class com.adt.po.User"; g'V,K\TG
Query query = getSession().createQuery EZ^M?awB4
4'XCO+i#
(querySentence); &XSe&1
count = ((Integer)query.iterate().next c1StA
G[!<mh4h|
()).intValue(); a0Q\]S
return count; CvqUaHW@
} ;sd] IZ$#
YHr<`Q</
/* (non-Javadoc) 'deqF|Iox
* @see com.adt.dao.UserDAO#getUserByPage zuvP\Y=V`
|R (rb-v
(org.flyware.util.page.Page) J+*n}He,
*/ 9R4q^tGR\
publicList getUserByPage(Page page)throws
5<?/M<i
]BBjFs4#
HibernateException { ]yA_N>k2K
String querySentence = "FROM user in class ^Xslj
SMh[7lU`
com.adt.po.User"; JP 8v2)
p
Query query = getSession().createQuery uB35CRd
i%9xt1c_
(querySentence); BU;E6s>P
query.setFirstResult(page.getBeginIndex()) CB?,[#r5f
.setMaxResults(page.getEveryPage()); q.PXO3T
return query.list(); 8 9f{8B]z
} mKBPIQ+ZS
1PT0<C-
} vjD||!g'
on0>_-n)
Y ptP_R:2p
sTO9>~sj
Z6oA>D
至此,一个完整的分页程序完成。前台的只需要调用 0G/_"}@
)UG<KcdI
userManager.listUser(page)即可得到一个Page对象和结果集对象 MIwkFI8
!,>9?(
的综合体,而传入的参数page对象则可以由前台传入,如果用 I`EgR?5 `
]}dAm S/
webwork,甚至可以直接在配置文件中指定。 NeY,Of|
woR }=\K
下面给出一个webwork调用示例: T13Jn o
java代码: .R{P%r
B!z5P"C(~
}4"T#
[n#
/*Created on 2005-6-17*/ F#XzhDs
package com.adt.action.user;
|HB
8Wyv!tL
import java.util.List; I;Bci m;
OAtn.LU
import org.apache.commons.logging.Log; *|k/l I
import org.apache.commons.logging.LogFactory; i fbO<
import org.flyware.util.page.Page; D[}qhDlX
VcR(9~
import com.adt.bo.Result; M]OZS\9.B
import com.adt.service.UserService; *1
l"|=_&s
import com.opensymphony.xwork.Action; BA|*V[HBE
`1"Xj ^
YM
/** w
B[H&
* @author Joa +46?+kKt
*/ 3L(vZ2&
publicclass ListUser implementsAction{ {F+iL&e)
n:[GK_
privatestaticfinal Log logger = LogFactory.getLog 9dD;Z$x&Xk
zAdZXa[MRY
(ListUser.class); ;?0r,0l2$
En/EQ\T@F
private UserService userService; /*5lO;!s{
ar|!iU
private Page page; 9q!./)
xBi``x2eY
privateList users; ]pP [0S
yjxv D
/* 96
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* (non-Javadoc) q%A.)1<'_
* I<ta2<h
* @see com.opensymphony.xwork.Action#execute() AVbGJ+
*/ ygquQhf5
publicString execute()throwsException{ h*\/{$y
Result result = userService.listUser(page); eC41PQ3=1'
page = result.getPage(); o>Jr6:D(
users = result.getContent(); rb@{ir
return SUCCESS; #q%V|Ajq
} ",qJG]_ <
9n[ovX 7n!
/** s0x;<si_
* @return Returns the page. #y&O5
*/ L@HWm;aN
public Page getPage(){ n:wZL&ZV0
return page;
Gt;59}
} 1ti4 ZM
3A.T_mGCs
/** R3=]Av46
* @return Returns the users. |SF5'\d'
*/ -<tfbaA
publicList getUsers(){ 'u{DFMB-A
return users; d]6#pSE
} U}Aoz|
J_PbRb
/** >'X[*:Cx
* @param page 60 z =bd]
* The page to set.
<c&6M
*/ /
!*+9+h
publicvoid setPage(Page page){ )2jBhT
this.page = page; <..|:0Q&~
} 1v^eXvY
\E<t'\>@X
/** [10;Mg
* @param users UI>?"b6
L
* The users to set. uY6|LTK&x
*/ APA:K9jD
publicvoid setUsers(List users){ x#{.mN
this.users = users; R2[-Q"|Ra
} u\zP`Y
hqKftk)+
/** (\M&Q-xZ
* @param userService 7#BUd/
* The userService to set. ()>,L?y
*/ %!i|"FNc
publicvoid setUserService(UserService userService){ EecV%E
this.userService = userService; C{8d^SCA"
} 1k8zAtuj
} 6X@$xe847[
dNL<O
xiW;Y{kZ
s;;"^5B.
T$ )dc^
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, _v9P0W^.7
/{9"O y7E
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 _a 40lcP
VV1I2YcKt
么只需要: 8T#tB,<fFW
java代码: \%FEQa0u
,{br6*E
GDW$R`2
<?xml version="1.0"?> J!GWP:b3
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork 1/H9(2{L
g}B|ZRz+{
1.0//EN" "http://www.opensymphony.com/xwork/xwork- @m=xCg.Z
b&V}&9'[M;
1.0.dtd"> I;<aJo6Yl
EhOy<f[4W
<xwork> sX~
`Vn&
m%bw$hr
<package name="user" extends="webwork- /bd1Bi
LPNJuz
interceptors"> _K?{DnTb
2/c^3[ccR
<!-- The default interceptor stack name oe8sixZ[
L/VlmN_v>s
--> $C;) Tlh
<default-interceptor-ref dSkW[r9Z%l
RnX:T)+o
name="myDefaultWebStack"/> f/Lyc=-]
mXH\z
<action name="listUser" q)ns ui(
jd]YKaI
class="com.adt.action.user.ListUser"> x]Nk T
<param |aT&rpt
K; +w'/{
name="page.everyPage">10</param> 6jKZ.S+s)
<result GuV.7&!x
,y+}0q-Ou
name="success">/user/user_list.jsp</result> b5MCOW1+
</action> /Y>$w$S
2)A% 'Akf
</package> xSQ:#o=8G
i'$V'x'k
</xwork> VR @V3 ~
{F/0pvP9
csPziH$wl
nYcj6?
z|o7k;raH
fU )@Lj1Wo
这样就可以通过配置文件和OGNL的共同作用来对page对象设置初值 e7(iMe
OUd&fUmH
了。并可以通过随意修改配置文件来修改每页需要显示的记录数。 QD6in>+B@
(Mk9##R#
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 _i=431Z40
7$l! f
._uXK[c7P
"lFS{7
^11y8[[
我写的一个用于分页的类,用了泛型了,hoho <@DF0x!
c==5 cMUg
java代码: _NfdJ=[Xh
/YP,Wfd%
a,GOS:?O5
package com.intokr.util; 29xm66
m+t<<5I[-
import java.util.List; m0I)_R#X[
_</>`P[
/** m~[4eH,
* 用于分页的类<br> \; 9log<Z
* 可以用于传递查询的结果也可以用于传送查询的参数<br> m44"qp
* V__|NVoOm
* @version 0.01 ;.O#|Z[
* @author cheng [9wuaw"~[Z
*/ KI@OEy
public class Paginator<E> { b9F:X
privateint count = 0; // 总记录数 gQ< >S
privateint p = 1; // 页编号 S,ENbP%0r
privateint num = 20; // 每页的记录数 lUL6L4m
privateList<E> results = null; // 结果 pk%%}tP<
m| /?((s
/** I%^Bl:M
* 结果总数 !mjrI "_
*/ ^\ N@qL
publicint getCount(){ yHXQCWY{8;
return count; Ft<6`C
} W>+/N4
;?{N=x8
publicvoid setCount(int count){ gB3Tz(!
this.count = count; \ah.@s
} 8 h.Dc&V
dR9[K4`p/
/** pie,^- _.g
* 本结果所在的页码,从1开始 sp-){k
* 7f$ hg8
* @return Returns the pageNo. )K.'sX{B
*/ `kRv+Qwfa
publicint getP(){ ^Fn~@'
return p; iI]E%H}
} mRECdGst
Knjg`f
/** DjMhI_Yu
* if(p<=0) p=1 pX/42W
* CJ~gE"
* @param p o^\L41x3
*/ Rxf.@E
publicvoid setP(int p){ EOn[!
if(p <= 0) #~I.F4
p = 1; s"xiGp9
this.p = p; A*a:#'"*N
} Z8vR/
A7hWAq
/** ssx#\
* 每页记录数量 U9/>}Ni%3G
*/ jgyXb5GY
publicint getNum(){ y.6Yl**l
return num; &~
.n}h&
} %u@}lG k
8wX|hK!Gz
/** 7_^JgA|Kk7
* if(num<1) num=1 A4mnm6Tf
*/ -Z<V?SFOK
publicvoid setNum(int num){ qQ/<\6Sl
if(num < 1) z7PmyU
>
num = 1; BM+>.
this.num = num; vyXL F'L
} =*\(Y(0
rF:l+I]
/** dSkx*#FEE
* 获得总页数 X[;-SXq
*/ r1R\cor
publicint getPageNum(){ [izP1A$r#Q
return(count - 1) / num + 1; c_Fz?R+f?K
} KM&bu='L^
`}o{o
/** 3$#=*Zp
* 获得本页的开始编号,为 (p-1)*num+1 BHrNDpv
*/ '1NZSiv+C?
publicint getStart(){ T {B\1|2w
return(p - 1) * num + 1; pY"&=I79tb
} 032PR;]
V=-hqo(
/** SYaL@54
* @return Returns the results. I;rh(FMV
*/ !IAd.<,
publicList<E> getResults(){ p/4}SU
return results; ?'%9
} - D^.I
wVac6q
public void setResults(List<E> results){ 9|5>?'CqP
this.results = results; mJFFst,
} J,,+JoD
%YV3-W8S0
public String toString(){ <v+M ~"%V
StringBuilder buff = new StringBuilder .~Y%
AI
D FN
(); i8 fUzg)
buff.append("{"); wpS $-
buff.append("count:").append(count); 68YJ@(iS
buff.append(",p:").append(p); r3mQoTvnv
buff.append(",nump:").append(num); ;UoXj+Z
buff.append(",results:").append g'nN#O
t#sw{RO
(results); %o4HCzId<
buff.append("}"); 6Cvg-X@
return buff.toString(); A;e0h)F$-
} b]XDfe
0{zA6Xu
} OYwH$5
6S6E
1~
^_o9%)RL(