Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 rqF PUp
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 p9s~WD/K
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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 cw5YjQ8 9
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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 3P6'*pZ
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。
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分页支持类: zHdp'J"
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java代码: T^nX+;:|
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package com.javaeye.common.util; v
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import java.util.List; OeAPBhTmFj
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publicclass PaginationSupport { D/:)rj14b
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publicfinalstaticint PAGESIZE = 30; i&HV8&KygN
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privateint pageSize = PAGESIZE; Dw#&x/G
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privateList items; _bd#C
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privateint totalCount; d#d~t[=
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privateint[] indexes = newint[0]; uc<@
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privateint startIndex = 0; xsTxc&0^
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public PaginationSupport(List items, int AO]lXa
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totalCount){ J6%op{7/
setPageSize(PAGESIZE); ^KaMi_--
setTotalCount(totalCount); B.G!7>=
setItems(items); f2u2Ns0Ym
setStartIndex(0); 7wqwDE
} #NE^f2
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public PaginationSupport(List items, int `o3d@Vc
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totalCount, int startIndex){ :I$2[K
setPageSize(PAGESIZE); {S}@P~H=
setTotalCount(totalCount); Y o(B8}?0!
setItems(items); E+)Go-rS(
setStartIndex(startIndex); sWC"^ S o
} {DK:"ep
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public PaginationSupport(List items, int BJE <~"
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totalCount, int pageSize, int startIndex){ =_H39)|T
setPageSize(pageSize); u l%bo%&~
setTotalCount(totalCount); l
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setItems(items); #TWc` 8
setStartIndex(startIndex); <S}qcjG
} kW~F*
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publicList getItems(){ o{he)r6)_
return items; VM,ZEt3Vy
} Za6oYM_z
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publicvoid setItems(List items){ z3C^L
this.items = items; 16>uD;G
} J:u|8>;
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publicint getPageSize(){ S8=4C`> jf
return pageSize; m?j!0>
} SRTpE,
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publicvoid setPageSize(int pageSize){ }$)<k
this.pageSize = pageSize; *Vl
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} jvV8`BQ{
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publicint getTotalCount(){ c7F&~RLC
return totalCount; X
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} H5s85"U#
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publicvoid setTotalCount(int totalCount){ 752wK|o0|;
if(totalCount > 0){ vdm?d/0(^
this.totalCount = totalCount; /pU6trIM
int count = totalCount / (M+<^3c
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pageSize; kpH;D=;
if(totalCount % pageSize > 0) Q
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count++; R`Lm"5w
indexes = newint[count]; p*0Ve21i,
for(int i = 0; i < count; i++){ IR
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indexes = pageSize * E(tBN]W.
+29\'w,
i; {h"\JI!
}
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}else{ B@]7eVo
this.totalCount = 0; `I8^QcP
} swlWe}1
} ,}tdfkZFYl
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publicint[] getIndexes(){ Zir`IQ$
return indexes; DQ\&5ytP
} yj~"C$s
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publicvoid setIndexes(int[] indexes){ =%\6}xPEl<
this.indexes = indexes; pxxFm~"d
} qDM[7q3.
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publicint getStartIndex(){ ak) -OL1
return startIndex; @MB _gt)7?
} 4Aew
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publicvoid setStartIndex(int startIndex){ Qcy`O
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if(totalCount <= 0) 38rZ`O*D
this.startIndex = 0; oKi1=d+T
elseif(startIndex >= totalCount) io{H$ x(
this.startIndex = indexes 1N!g`=}
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[indexes.length - 1]; ;q; C^l
elseif(startIndex < 0) 8-a6Q|
this.startIndex = 0; uX +<`3O
else{ 6I.m c
this.startIndex = indexes \83A|+k
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[startIndex / pageSize]; n2mw@Ay!
} ms7 7{A3
} %^=!s
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publicint getNextIndex(){ 1[BvHOI2
int nextIndex = getStartIndex() + g>xUS_d>
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pageSize; J,G9m4Z7
if(nextIndex >= totalCount) {7Avba
return getStartIndex(); (VaN\+I:T
else RVnyl`s
return nextIndex; h+3Z.WKhwP
} `4.sy +2
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publicint getPreviousIndex(){ lo UwRz
int previousIndex = getStartIndex() - ` G=L07
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pageSize; :6$4K"^1
if(previousIndex < 0) +;*(a3Gp
return0; 18"VB50b}
else 2nU
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return previousIndex; iW@Vw{|i I
} Hu9R.[u
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} "QO/Jls
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抽象业务类 wUCDJY:,1
java代码: :"P hkR
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/** %HF$
* Created on 2005-7-12 pOVghllO
*/ zrU$SWU
package com.javaeye.common.business; tOM3Gs~o6z
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import java.io.Serializable; xbrmPGpW$
import java.util.List; {vT55i<mk
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import org.hibernate.Criteria; to!W={S<ol
import org.hibernate.HibernateException; {QS@Ugf
import org.hibernate.Session; e#6&uFce
import org.hibernate.criterion.DetachedCriteria; 5uV"g5?w
import org.hibernate.criterion.Projections; UW/3{2
import Ac!&j=ZE
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org.springframework.orm.hibernate3.HibernateCallback; l?JO8^Nn
import jqGo-C~
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org.springframework.orm.hibernate3.support.HibernateDaoS aT1CpY=T|.
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upport; UI<PNQvo9
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import com.javaeye.common.util.PaginationSupport; 9j?hF$L"
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public abstract class AbstractManager extends ]EM)_ :tRf
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HibernateDaoSupport { *lerPY3 q
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privateboolean cacheQueries = false; r$r&4dY
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privateString queryCacheRegion; L_gsG|xX
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publicvoid setCacheQueries(boolean < k+fKl
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cacheQueries){ *mQDS.'AB@
this.cacheQueries = cacheQueries; RC8)f8n
} ^KZAYB9C
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publicvoid setQueryCacheRegion(String {rb-DB-/5M
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queryCacheRegion){ Q}Ze-JIL$
this.queryCacheRegion = XJJ[F|k~
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queryCacheRegion; CFBUQMl>
} GIC"-l1\
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publicvoid save(finalObject entity){ [^U;
getHibernateTemplate().save(entity); xV,4U/T
} c#n4zdQd]5
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publicvoid persist(finalObject entity){ ?K4.L?D#J
getHibernateTemplate().save(entity); I[g?Ju >
} 5xMA~I 0c
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publicvoid update(finalObject entity){ z<oE!1St
getHibernateTemplate().update(entity); TRk
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} {(M&-~Yh
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publicvoid delete(finalObject entity){ ~Q_)>|R2
getHibernateTemplate().delete(entity); *X=@yB*aK
} L,L ~
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publicObject load(finalClass entity, 0H OoKh
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finalSerializable id){ o5=)~D{/G3
return getHibernateTemplate().load NoJnchiU
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(entity, id); ^J#?hHz
} 3^02fy
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publicObject get(finalClass entity, +QIGR'3u
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finalSerializable id){ yfM>8"h@
return getHibernateTemplate().get V6@*\+:3)
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(entity, id); `qf\3JT\
} nc3ltT,R
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publicList findAll(finalClass entity){ Sl. KLc@@
return getHibernateTemplate().find("from Vq3]7l
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" + entity.getName()); P\q <d
} R<n8M"B
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publicList findByNamedQuery(finalString $@[dm)M
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namedQuery){ DA+A >5/
return getHibernateTemplate ZL4l
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().findByNamedQuery(namedQuery); V17>j0Ev$W
} 9tzoris[~
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publicList findByNamedQuery(finalString query, ig{A[7qN
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finalObject parameter){ --in+
return getHibernateTemplate RNv{n
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().findByNamedQuery(query, parameter); 0Y5LDP
} v%H"_T
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publicList findByNamedQuery(finalString query, mJ0}DJiX$
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finalObject[] parameters){ g(-;_j!=
return getHibernateTemplate Ci]'G>F@"
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().findByNamedQuery(query, parameters); Q3'fz 9v
} 0hrCG3k.91
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publicList find(finalString query){ M|/oFV
return getHibernateTemplate().find Np.no$_
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(query); u:_sTfKm&
} [NHg&R H
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publicList find(finalString query, finalObject QuSV&>T\
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parameter){ SX1X<9
return getHibernateTemplate().find o2;(VSKhS
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(query, parameter); zb"rMzCH
} SQh+5
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public PaginationSupport findPageByCriteria jMN)?6$=
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(final DetachedCriteria detachedCriteria){ lq:]`l,6@
return findPageByCriteria Sp 7u_Pq{
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); S:/{
} 7n\ ThfH{
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public PaginationSupport findPageByCriteria <_"B}c/2$
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(final DetachedCriteria detachedCriteria, finalint O4m(Er@a
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startIndex){ 9 wAA.
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return findPageByCriteria "Z;~Y=hC13
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(detachedCriteria, PaginationSupport.PAGESIZE, <KKDu$W|T
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startIndex); vTpStoUM
} mfZ)^X
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public PaginationSupport findPageByCriteria 6tOCZ'f
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(final DetachedCriteria detachedCriteria, finalint RTK}mhnV
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pageSize, J5O.*&
finalint startIndex){ ID)^vwn
return(PaginationSupport) t2"@Ps&1|
qv
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getHibernateTemplate().execute(new HibernateCallback(){ 24//21m
publicObject doInHibernate DH:J
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(Session session)throws HibernateException { q<n[.u1@
Criteria criteria = F;#zN
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detachedCriteria.getExecutableCriteria(session); 92ZWU2"
int totalCount = ovo/!YJ2
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((Integer) criteria.setProjection(Projections.rowCount y>$1UwQ
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()).uniqueResult()).intValue(); '0Lov]L
criteria.setProjection BYS lKTh
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(null); M ~als3
List items = H#+\nT2m
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criteria.setFirstResult(startIndex).setMaxResults 3S5^`Ag#
@|BD|{k
(pageSize).list(); uG;?vvg>
PaginationSupport ps = PkTfJQP8
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new PaginationSupport(items, totalCount, pageSize, b \:~ ;
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startIndex); 3 -tO;GKb
return ps; Dv@PAnk3C
} {-HDkG' 8
}, true); s2^B(wP
} sm1;MF]/u
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public List findAllByCriteria(final (%bE~Q2P*<
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DetachedCriteria detachedCriteria){ COSTV>s;
return(List) getHibernateTemplate IK'F{QPH
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().execute(new HibernateCallback(){ \b$<J.3
publicObject doInHibernate 5X0QxnnV
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(Session session)throws HibernateException { r?pZ72q
Criteria criteria = 1SUzzlRx
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detachedCriteria.getExecutableCriteria(session); :N2E}hxk
return criteria.list(); P[FV2R~
} T^]7R4Fg
}, true); /YFa
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} Q/py qe G
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public int getCountByCriteria(final \]8VwsP
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DetachedCriteria detachedCriteria){ `a
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Integer count = (Integer) +%XnMl
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getHibernateTemplate().execute(new HibernateCallback(){ +"8}R~`!
publicObject doInHibernate yAG+] r
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(Session session)throws HibernateException { xIL#h@dz
Criteria criteria = 0Gsu
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detachedCriteria.getExecutableCriteria(session); (9]6bd
return zT7"VbP
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criteria.setProjection(Projections.rowCount O#EqG.L5
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()).uniqueResult(); :3^dF}>
} p x#suy
}, true); #Ao !>qCE
return count.intValue(); 1[-vD=
} 9Kbw
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} Lc]1$
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用户在web层构造查询条件detachedCriteria,和可选的 u1^\MVO8
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 ,?(ciO)
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PaginationSupport的实例ps。 Jf_%<\ O
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ps.getItems()得到已分页好的结果集 Uw)=WImz[
ps.getIndexes()得到分页索引的数组 CZ(`|;BC*
ps.getTotalCount()得到总结果数 ubbnFE&PD
ps.getStartIndex()当前分页索引 G;s"h%Xw98
ps.getNextIndex()下一页索引 {x{H$ f
ps.getPreviousIndex()上一页索引 #{*LvI&
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 ! E0!-UpY
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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 aSL6zye
,
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一下代码重构了。 `/4:I
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我把原本我的做法也提供出来供大家讨论吧: YQd:M%$
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首先,为了实现分页查询,我封装了一个Page类: $a(`ve|
java代码: 1~\M!SQ)
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/*Created on 2005-4-14*/ xu\eX x6H
package org.flyware.util.page; n]y EdL/1
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/** $1Z6\G O
* @author Joa ;:]\KJm}?
* ?S tsH
*/ =a$Oecg?
publicclass Page { }k7'"`#?"
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/** imply if the page has previous page */ vzXag*0
privateboolean hasPrePage; YGk9b+`
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/** imply if the page has next page */ hXB|g[zT
privateboolean hasNextPage; .L EY=j!-s
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/** the number of every page */ y1pu R7
privateint everyPage; qP1FJ89H
Vn|1v4U!
/** the total page number */ ~h)&&'a
privateint totalPage; Vrkf(E3_V
PsnGXcj
/** the number of current page */ ke%pZ7{u
privateint currentPage; 8P2 J2IU
)Gk`[*q ;
/** the begin index of the records by the current O !&,5 Dy
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query */ wtH~-xSB|
privateint beginIndex; XP3xJm3
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/** The default constructor */ _}gtcyx
public Page(){ v }\,o%t^
*%gF2@=r8F
} x#H
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/** construct the page by everyPage f_=~H<j!
* @param everyPage ,S&z<S_
* */ rwf^,r"r
public Page(int everyPage){ 6b=q-0yj
this.everyPage = everyPage; Z?G&.# :
} 0-d>I@j
/4irAG% Oj
/** The whole constructor */ 5@!st
public Page(boolean hasPrePage, boolean hasNextPage, I#rubAl
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int everyPage, int totalPage, D(]E/k@;~
int currentPage, int beginIndex){ ytAWOt}`
this.hasPrePage = hasPrePage; \6!W05[ Q
this.hasNextPage = hasNextPage; A1i!F?X
this.everyPage = everyPage; DAO]uh{6
this.totalPage = totalPage; ]!
*[Q\
this.currentPage = currentPage; z-T{~{q
this.beginIndex = beginIndex; $8~e}8dt|
} v]VWDT
`
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/** }}
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* @return rS8 w\`_
* Returns the beginIndex. ~O6\6$3b5E
*/ nH-V{=**
publicint getBeginIndex(){ $XnPwOj
return beginIndex; s1j{x&OSq
} g(E"4M@t!
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/** gl%`qf6:O
* @param beginIndex %;"@Ah
* The beginIndex to set. c1XX~8
*/ 5*-3?
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publicvoid setBeginIndex(int beginIndex){ 7^6uG6
this.beginIndex = beginIndex; K9Hqq7"%
} /j2H A^GT
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/** na+d;h*~y
* @return 9i q""
* Returns the currentPage. #]Y>KX2HG
*/ mN_Z7n;^eh
publicint getCurrentPage(){ c3TKl/
return currentPage; #FxPj-3(ix
} jM)C4ii.-$
k@mVxnC
/** 4=8QZf0\
* @param currentPage \;X+X,M
* The currentPage to set. 5\fCd|
*/ zg)sd1@
publicvoid setCurrentPage(int currentPage){ K4ZolWbU
this.currentPage = currentPage; eOT+'[3"
} s%4M$e
RW'nUL?_\
/** 07v!Zj
* @return 5*g]qJF
* Returns the everyPage. 9LC&6Q5O&
*/ i5}4(sV
publicint getEveryPage(){ 5` D-
return everyPage;
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} (qMj-l
,M5}4E7L%s
/** w f.T3
* @param everyPage J Yb}Zw;
* The everyPage to set. dEa<g99[?
*/ 2BXy<BM @
publicvoid setEveryPage(int everyPage){ ~nLN`Hd
this.everyPage = everyPage; bC!`@/
} OX]V)QHVZ
cZ8.TsI~
/** zmuMWT;
* @return x Gk6n4Gg
* Returns the hasNextPage. o+B:#@9?
*/ #]WqM1u
publicboolean getHasNextPage(){ !A3-0zN!
return hasNextPage; I{'f|+1
} `_ %S
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/** PUJ2`iP1^3
* @param hasNextPage hB;VCg8
* The hasNextPage to set. G"5D< ]
*/ Lo.rvt
publicvoid setHasNextPage(boolean hasNextPage){ am1[9g8L
this.hasNextPage = hasNextPage; x\e;+ubt}
} J5Z%ImiT^O
,8'>R@o
/** @D^^_1~
* @return u^Ku;RQo
* Returns the hasPrePage. Uh
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*/ PXoz*)tk
publicboolean getHasPrePage(){ :(|'S4z
return hasPrePage; E_z;s3AXQ
} uQ$^;Pr
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/** CbBSFKM
* @param hasPrePage e> rRTN
* The hasPrePage to set. eYUr-rN+)z
*/
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publicvoid setHasPrePage(boolean hasPrePage){ .0 )Y
this.hasPrePage = hasPrePage; Yj|eji7y
} Vgb *% I
AI vXb\wL
/** 9I7\D8r
* @return Returns the totalPage. }GMbBZ:nKK
* ^jB8Q
*/ RrZM&lXY
publicint getTotalPage(){ }kHdK vZ
return totalPage; ZIR0PQh\
} P;[OWSR[d
1F'1>Bu~
/** WO5O?jo'
* @param totalPage b3-eR5U/
* The totalPage to set. }TQ{`a@
*/ Am0{8
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publicvoid setTotalPage(int totalPage){ >Hb^P)3
this.totalPage = totalPage; KOq;jH{$
} moj]j`P5a
/
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} gJiK+&8I
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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 c
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个PageUtil,负责对Page对象进行构造: 5RH2"*8T
java代码: k#Of]mXXz
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/*Created on 2005-4-14*/ yH 9!GS#
package org.flyware.util.page; |s#'dS;
kd:$oS_*s
import org.apache.commons.logging.Log; #PDf,^
import org.apache.commons.logging.LogFactory; SKuIF*"!S
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k
/** _\PNr.D8
* @author Joa o}Odw;
* mME4 l
*/ n~V4nj&_T
publicclass PageUtil { 1(zsOeX
H7Uli]e3
privatestaticfinal Log logger = LogFactory.getLog ,t{,_uPJY
)3YtIH_
(PageUtil.class); 4h!f/aF'
,/&'m13b/L
/** l.\re"Q
* Use the origin page to create a new page ECdvX0*a
* @param page Tu{&v'!j6
* @param totalRecords :WI.LKlo~
* @return pMg3fUIM
*/ zsU=sTsL
publicstatic Page createPage(Page page, int ?&LZB}1R
\$aF&r<R
totalRecords){ 9`jcC-;iv
return createPage(page.getEveryPage(), fJ\sguZ
^_t%kmL`
page.getCurrentPage(), totalRecords); )VCzn~uf
} IEjP<pLe
x83
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/** Nw& !}#m
* the basic page utils not including exception hmx=
35
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handler n,eJ$2!J
* @param everyPage YSJy`
* @param currentPage F/m^?{==~*
* @param totalRecords -LDCBc"
* @return page *#%9Rp2|
*/ uPYmHA}_/
publicstatic Page createPage(int everyPage, int gj\)CBOv
q#Zs\PD
currentPage, int totalRecords){ ZvYLL{>}w
everyPage = getEveryPage(everyPage); QB:i/9
currentPage = getCurrentPage(currentPage); 4k/VBZB
int beginIndex = getBeginIndex(everyPage, E3@QI?n^^
{mWui9 %M
currentPage); }>^Q'BW;65
int totalPage = getTotalPage(everyPage, *19ax&|*S
{7cX#1
totalRecords); EM7+VO(
boolean hasNextPage = hasNextPage(currentPage, 6Ao%>;e*
LA_3=@2.H
totalPage); n .!Ym
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boolean hasPrePage = hasPrePage(currentPage); >@WX>0`ht
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returnnew Page(hasPrePage, hasNextPage, }?cGf-c
everyPage, totalPage, tt%MoQ)
currentPage, A*./,KT
_,;j7%j
beginIndex); 5Zmw} M
} oLWJm
i{!T&8
privatestaticint getEveryPage(int everyPage){ xD&^j$Em
return everyPage == 0 ? 10 : everyPage; Lb{e,JH
} S[tE&[$(p
nf1#tlIJd
privatestaticint getCurrentPage(int currentPage){ IchCACK
return currentPage == 0 ? 1 : currentPage; hlu:=<B
} ,+qVu,
hjO*~
privatestaticint getBeginIndex(int everyPage, int WwC 5!kZ
2([2Pb3<"
currentPage){ &U+ _ -Ph
return(currentPage - 1) * everyPage; \BWykA>
} 7 r|(}S
Q0Nyqhvi
privatestaticint getTotalPage(int everyPage, int )uv=S;+
_3]][a,
totalRecords){ {_(\`>
int totalPage = 0; DC1'Kyk
=0@&GOq
if(totalRecords % everyPage == 0) yNm:[bOER
totalPage = totalRecords / everyPage; Tirux ;
else Xh J,"=E+
totalPage = totalRecords / everyPage + 1 ; nR4y`oP+
tb:L\A^:
return totalPage; %Pksv}
} l5+gsEux]
izKfU?2]X@
privatestaticboolean hasPrePage(int currentPage){ |F.)zC5{
return currentPage == 1 ? false : true; 7?B.0>$3>V
} o!:8nXw
yq+!czlZ
privatestaticboolean hasNextPage(int currentPage, Z/^ u
&a/__c/l
int totalPage){ USN8N (
return currentPage == totalPage || totalPage == "NRDNqj(
!6Sd(2
0 ? false : true; !*2%"H*
} fN"(mW>!
;q0uE:^S
{lth+{&L#
} `mye}L2I
64-#}3zL
xEuN
T#pk]c6Q
GE>[*zN
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 q1E:l!2al
)2,eFNB#n
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 T[=S$n-'
gyS+9)gY
做法如下: v/ *Y#(X
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 2<mW\$
sH[
-W-
的信息,和一个结果集List: [m+iQVk'
java代码: @aQ1khEd
y~IuP c
yL;M"L
/*Created on 2005-6-13*/ c9R5w.t:
package com.adt.bo; M MzGd:0b
w&4~Q4
import java.util.List; y7KzW*>g:
~2EH OO{
import org.flyware.util.page.Page; e!fqXVEVR
65ly2gl
/** (M
=Y&M'f
* @author Joa m]*Bx%-1c
*/ vK$"# F~
publicclass Result { *5<Sr q'
1 nvTce
private Page page; cI]WrI2CQa
?Qb<-~~
j1
private List content; @\&m+;6
Th`skK&U
/** S osj$9E
* The default constructor LQnkcV
*/ 10#oG{9
public Result(){ VL'
fP2
super(); R:p62c;Tv0
} '03->7V
%p&k5:4<"#
/** q9"=mO0J+
* The constructor using fields ,]}?.g
* >:=|L%]s;\
* @param page (;. AS
* @param content ?S?2 0
*/ }HEvr)v9
public Result(Page page, List content){ >zkRcm
this.page = page; $./bjV%
this.content = content; Ifk#/d
} s] /tYJYl
7VK}Dy/Vvn
/** .oEmU+
* @return Returns the content. X0{/ydGF8
*/ k`".
publicList getContent(){ :V)lbn\
return content; 8Ry74|`=R
} 5>6PH+Oq
Iqs+r?
/** mVtXcP4b
* @return Returns the page. k%[3Q>5iM
*/ xUF_1hY
public Page getPage(){ RvJ['(-
return page; N8KQz_]9I
} @`FCiH M
fAZiC+
/** )'l*Tl
* @param content A?G IBjs
* The content to set. 4`#F^2r!
*/ vi@Lz3}::
public void setContent(List content){ )m3q2W
this.content = content; `P Xz
} reo{*)%
(I@bkMp
/** E^w:KC2@
* @param page ZxGP/D
* The page to set. 2/,0iwj-
*/ uH3D{4
publicvoid setPage(Page page){ D+lzFn$3
this.page = page; lq.Te,Y%w
} 3Q/#T1@
} B*!WrB:s
4YZS"K'E
~-a'v!
wPbkUVO
x*oWa,
2. 编写业务逻辑接口,并实现它(UserManager, P7B:%HiAx
Qy#)Gxp
UserManagerImpl) wV?,Z!\Z
java代码: ~.PP30'
GFSt<k)
[NnauItI
/*Created on 2005-7-15*/ i`
A
package com.adt.service; M(|
S{',QO*D6
import net.sf.hibernate.HibernateException; G0n'KB
AvR2_
import org.flyware.util.page.Page; _<ut)G^9
g%[n4
import com.adt.bo.Result; t+CWeCp,
T5wjU*=IL
/** EoX_KG{
* @author Joa dQy>Nmfy
*/ W{XkVKe1a
publicinterface UserManager { +@X5!S6
5)1+~ B
public Result listUser(Page page)throws ^EVc 95|Z
{Hr$wa~
HibernateException; I
PE}gp
_eLWQ|6Fx
} 59(U `X
QD{:vG
g
iq?#rb P#I
9^P2I)aD
!BU)K'mj
java代码: Kex[ >L10G
0ZAj=u@O
g|P C$p-z+
/*Created on 2005-7-15*/ 0f ER*.F
package com.adt.service.impl; F{k+7Ftc
Dj-s5pAW
import java.util.List; gG54:
N132sN2
import net.sf.hibernate.HibernateException; fYebB7Pv
WUAJjds
import org.flyware.util.page.Page; fbZibcQ%k
import org.flyware.util.page.PageUtil; OH<?DcfeL
T0j2a&Pv
import com.adt.bo.Result; 3L-^<'~-k;
import com.adt.dao.UserDAO; yh;Y,;4
import com.adt.exception.ObjectNotFoundException; :ZdUx
import com.adt.service.UserManager; ~Pk0u{,4XQ
4yMW^:@
/** m$>iS@R
* @author Joa =fc:6JR
*/ ^ L:cjY/
publicclass UserManagerImpl implements UserManager { zH)_vW
l QPqcZd
private UserDAO userDAO; 4C~UcGMv\
"
oy\_1|
/** jm>3bd
* @param userDAO The userDAO to set. Hr;h4J
*/ &UAe!{E0
publicvoid setUserDAO(UserDAO userDAO){ 5,+\`!g
this.userDAO = userDAO; )J/HkOj"V
} uMXc0fs!$
.uZ7 -l
/* (non-Javadoc) 8uG0^h}
* @see com.adt.service.UserManager#listUser _3Q8n|
Mjpo1dw
(org.flyware.util.page.Page) @b!"joEy
*/ WoL9V"]
public Result listUser(Page page)throws B_3QQtjAl
exR^/|BR
HibernateException, ObjectNotFoundException { |oKu=/[K
int totalRecords = userDAO.getUserCount(); !7lj>B A>
if(totalRecords == 0) WbjF]b\
throw new ObjectNotFoundException #/J
'P[z
Uv?'m&_
("userNotExist"); {sN"(H4$
page = PageUtil.createPage(page, totalRecords); lpQP"%q
List users = userDAO.getUserByPage(page); l_FGZ!7
returnnew Result(page, users); a,'Cyv">
} _[Gb)/@mM
GA^mgm"O
} y<r}"TAf-
Uku5wPS
C77D{@SM
#*IVlchA"B
;cP8 ?U
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 C;1PsSE+A
u,i]a#K
询,接下来编写UserDAO的代码: 4~?2wvz G4
3. UserDAO 和 UserDAOImpl: .{dE}2^
java代码: ol!86rky
H9"= p
oC dGQ7G}
/*Created on 2005-7-15*/ \4~AI=aw,T
package com.adt.dao; HR{s&ho
10N,?a
import java.util.List; B<
;==|
&a~=b,
import org.flyware.util.page.Page; 3_ 2hC!u!K
VAj<E0>
import net.sf.hibernate.HibernateException; &/F_*=VE
P@ypk^v
/** B#N7qoi
* @author Joa .Oo/y0E^
*/ i*tv,f.(
publicinterface UserDAO extends BaseDAO { ~@c-*
g,lY ut
publicList getUserByName(String name)throws v+q<BYq
hYt7kq!"
HibernateException; >S&U.
4\Di,PPu
publicint getUserCount()throws HibernateException; ?9?4p@
e9@(/+
publicList getUserByPage(Page page)throws R8sck)k'}
^ "6f\
HibernateException; a+(j?_FyI
K^D82tP
} a|x8=H
A!HK~yk~Q
V:^H4WvL\W
9`X&,S~e
N=fz/CD)I
java代码: ]6~k4
W7e4pR?w
Y}1P~
/*Created on 2005-7-15*/ XL"=vbD
package com.adt.dao.impl; v&0d$@6/U
|^5 /(16
import java.util.List; az(5o
i.@*tIK
import org.flyware.util.page.Page; _EKF-&Q6
<c%n?QK{
import net.sf.hibernate.HibernateException; ;~ee[W$1
import net.sf.hibernate.Query; z[#6-T
&
#
cWHDRLX
import com.adt.dao.UserDAO; ya>N.h
b.Su@ay@(^
/** <q6`~F~|
* @author Joa 0/A-#'>
*/ 2ij/N%l
public class UserDAOImpl extends BaseDAOHibernateImpl U>3
>Ex
wXCyj+XB*
implements UserDAO { {visv{R<
}u^:MI
/* (non-Javadoc) -N^=@Yx)
* @see com.adt.dao.UserDAO#getUserByName ' o=E!?
~I)uWo
(java.lang.String) @a;sV!S{
*/ Yk7"XP[Y
publicList getUserByName(String name)throws twbcuaCTW
7+8bL{
HibernateException { XARSGAuw
String querySentence = "FROM user in class $MT}l
kgc.8
com.adt.po.User WHERE user.name=:name"; pGk"3.ce
Query query = getSession().createQuery eiB(VOJ
Q<'@V@H
(querySentence); 03"#J2b
query.setParameter("name", name); \(9p&"Q-
return query.list(); ;$6x=uZ
} 5`yPT>*#m>
}9}w8R~E
/* (non-Javadoc) {d}26 $<$]
* @see com.adt.dao.UserDAO#getUserCount() f(.6|mPp
*/ sN@j5p^jc
publicint getUserCount()throws HibernateException { MgP{W=h2
int count = 0; 0~i q G
String querySentence = "SELECT count(*) FROM TQ~&Y)".
W9jNUZVXE#
user in class com.adt.po.User"; yy))Z0E5
Query query = getSession().createQuery =#'+"+lQ }
GU#Q}L2
(querySentence); x 8M#t(hw
count = ((Integer)query.iterate().next `vH&K{
h9Z[z73_a
()).intValue(); 8!6<p[_
return count; okh0_4
} e@+v9Bs]q
Ei~]iZ}
/* (non-Javadoc) yUj;4vd
* @see com.adt.dao.UserDAO#getUserByPage o3= .T+B
'}fel5YV
(org.flyware.util.page.Page) JOgmF_(>Z
*/ f-s~Q4
publicList getUserByPage(Page page)throws kI]=&Rw
{"}+V`O{
HibernateException { 7(5]Ry:
String querySentence = "FROM user in class ;$[VX/A`f
QS%,7'EG
com.adt.po.User"; F]Pul|.l
Query query = getSession().createQuery S#hu2\9D,
gm}C\q9
(querySentence); FBbm4NB
query.setFirstResult(page.getBeginIndex()) &BTfDsxAK
.setMaxResults(page.getEveryPage()); B~BUWWMfp
return query.list(); .yG8B:7N2
} +}\29@{W
i63?"
} vnF g%M!
M +\rX1T
>pa\n9=Q^
=Y:5,.U
'H
FwP\HX
至此,一个完整的分页程序完成。前台的只需要调用 Hc"N&
%X[
JH-nvv
userManager.listUser(page)即可得到一个Page对象和结果集对象 krwf8!bI
)*+u\x_Hx
的综合体,而传入的参数page对象则可以由前台传入,如果用 Jn60i6/
yCZ2^P!a
webwork,甚至可以直接在配置文件中指定。 ]~ >@%v&
?<g|.HY/
下面给出一个webwork调用示例: @s3aR*ny$
java代码: A>[hC{
@t "~
Y9/{0TArG
/*Created on 2005-6-17*/ S]tkz*w0*
package com.adt.action.user; &~42T}GTWG
=CGD
~p`
import java.util.List; (PyTq
5:F
!;ZBL;qY9
import org.apache.commons.logging.Log; zmdWVFVv
import org.apache.commons.logging.LogFactory; 7d%A1}Bq$
import org.flyware.util.page.Page; ~ }Kp
0LZ=`tI
import com.adt.bo.Result; $)4GCP
import com.adt.service.UserService; +q$xw}+PK
import com.opensymphony.xwork.Action; _Eszr(zJ
j#4+-
/** P~n8EO1r
* @author Joa CuF%[9[cT
*/ ,,zd.9n
publicclass ListUser implementsAction{ z^YeMe
_95- -\
privatestaticfinal Log logger = LogFactory.getLog ;sm"\.jF
q.U*X5
(ListUser.class); !4i,%Z&6
b*@&c9I;q
private UserService userService; 0@JilGk1u
EaJDz`T}
private Page page; ~r{\WZ.
J~M H_N
privateList users; G* 8+h
cA2^5'$$
/* s0_-1VU
* (non-Javadoc) ab8oMi`z
* O-y6!u$6&
* @see com.opensymphony.xwork.Action#execute() ?r^
hmu"a
*/ hg$qbeUl
publicString execute()throwsException{ u4`mQ6
Result result = userService.listUser(page); +R3\cRM
page = result.getPage(); 3(cU)
users = result.getContent(); A%.J%[MVz
return SUCCESS; Q:'qw#P/C
} ]Y?{$M
G
ocb%&m;i
/** !hwzKm=%N
* @return Returns the page. ^aGZJiyJ
*/ f)p>nW?Z
public Page getPage(){ Aqx3!
return page; GhSL%y
} !C9ps]6
$]Q*E4(kV9
/** !:]s M-cCt
* @return Returns the users. H9oXZSm
*/ #i}# jMT
publicList getUsers(){ /k4^&
return users; OpWC2t)
} 34/]m/2NZK
lBizC5t!o
/** (= S"Kvb~#
* @param page ^KaqvG$ed
* The page to set. )*psDjZ7*
*/ P5yJO97
publicvoid setPage(Page page){ Bt|9%o06l
this.page = page; 4GMa5]Ft
} RT8_@8
c,3'wnui
/** 0})7of
* @param users Wto@u4
* The users to set. `'A(`. CL
*/ CF4Oh-f
publicvoid setUsers(List users){ _WRR
3
this.users = users; 4Zv.[V]iOO
} kxr6sO~
:,xyVb+
/** ^P3g9'WK
* @param userService }a #b$]Y
* The userService to set. .!7Fe)(x
*/ $M}k%Z
publicvoid setUserService(UserService userService){ X]3l| D
this.userService = userService; =hZ&66
} ft~|
} al3BWRq'f
+SZ%&
}"g21-T^
i?&4SG+2~K
Z>>gXh<e[
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, 8|S1|t,
FcA)RsMI*
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 Qwp\)jVi
:>AW@SoTp
么只需要: qb>|n1F_
java代码: =:CGl
h;4y=UU
P!)7\.7
<?xml version="1.0"?> +7U
A%q
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork 'NG^HLD/
( 7rz:
1.0//EN" "http://www.opensymphony.com/xwork/xwork- `[C v-
z1{E:~f
1.0.dtd"> a6#{2q
p ?Ij-uo"o
<xwork> "2vNkO##
=hOj8;2
<package name="user" extends="webwork- A/Fs?m{7U
]|((b/L3
interceptors"> hX'z]Am<
_4XoUE\\
<!-- The default interceptor stack name `ohF?5J,
-Z/6;2Q
--> c|R3,<Q]
<default-interceptor-ref `/gEKrhL-
[`Qp;_K?t
name="myDefaultWebStack"/> Gct&}]3pm
0%qctZy
<action name="listUser" YP
.%CD(K
VAF:Z
class="com.adt.action.user.ListUser"> \ eyQo>(
<param NXWIE4T>*^
QvK]<HEr
name="page.everyPage">10</param> DS[l,x
<result )=,9`+Zta
,,wyydG
name="success">/user/user_list.jsp</result> N#-kk3!Z;
</action> $&n240(
FgHB1x4;
</package> ZhJ|ZvJ
9`gGsC
</xwork> !7,K9/"
@6I[{{>X
Jq?^8y
S7#^u`'Q_^
yaYIgG
J7
*G/F
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 UtGd/\:
4?*"7t3
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。 33v%e
F|n$0vQ*
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 I%zo>s6
8G[Y9A(bmP
#LNB@E
L2/<+Zw
<76=H]h~
我写的一个用于分页的类,用了泛型了,hoho K9z_=c+
H/v37%p7
java代码: *C:q _/
6!Tf'#TV~!
WKYA9BaR
package com.intokr.util; }v(H
E%~}
\.{pZMM
import java.util.List; [}xIg8
9>$%F;JP44
/** |qudJucV
* 用于分页的类<br> w4<u@L
* 可以用于传递查询的结果也可以用于传送查询的参数<br> qdkTg: QJ,
* 6!}m$Dvt~
* @version 0.01 ETH#IM8J
* @author cheng sJYKt
*/ 0or6_y6
public class Paginator<E> { WX[dM
}L
privateint count = 0; // 总记录数 1WA""yb
privateint p = 1; // 页编号 )>#<S0>'j
privateint num = 20; // 每页的记录数 RAx]Sp
Q-S
privateList<E> results = null; // 结果 o y%g{,V
\Dsl7s=
/** as!|8JE`
* 结果总数 Kjca>/id
*/ in;+d~?
publicint getCount(){ `v/tf|v6
return count; ~E:/oV:4 >
} i7w}`vs
3bI|X!j
publicvoid setCount(int count){ ~BYEeUo;%v
this.count = count; 3z/O`z
} ?'$.
-z:
Zs K'</7
/** +[l{C+p
* 本结果所在的页码,从1开始 I}Gl*@K&O
* )*L?PT
* @return Returns the pageNo. cX=b q_
*/ @}rfY9o'
publicint getP(){ dU04/]modD
return p; [ Xo
J7
} '?!<I
&MGgO\|6
/** Z`1o#yZ
* if(p<=0) p=1 D<L{Z[
* h|/*yTuN.y
* @param p VT~
^:-]
*/ qI%9MI;BV
publicvoid setP(int p){ QX~72X=(
if(p <= 0) Hd@T8 D*A
p = 1; <wGTs6
this.p = p; XkfUPbU
} f.xSr!
r@V(w`
/** qaSv]k.
* 每页记录数量 1p5q}">z
*/ 93p9?4;n-
publicint getNum(){ [.#$hOsNR
return num; 'w$we6f
} apWrcaj
@Oc}\Rg
/** j~j
V`>A
* if(num<1) num=1 ne~#{q
*/ GH)+yD[o
publicvoid setNum(int num){ ~|d?o5W
if(num < 1) %KVRiX
num = 1; 5>k~yaju/
this.num = num; <HX-qNA?
} [(^''*7r+T
$/(/v?3][e
/** E6IL,Iq9
* 获得总页数 WAXrA$:3J
*/ 21J82M
publicint getPageNum(){ !m.')\4<
return(count - 1) / num + 1; 2!& ;ZcT,
} K0!#l Br
C&K(({5O
/** E]Gq!fA&<
* 获得本页的开始编号,为 (p-1)*num+1 ;0}"2aGY
*/ XXdMp poR
publicint getStart(){ 9*Mg<P"
return(p - 1) * num + 1; eMMiSO!3
} VQJ5$4a&
mp$II?hZ*
/** sy#j+gZ
* @return Returns the results. ON=ley
*/ KE1@z]
publicList<E> getResults(){ ]tV{#iIJ*
return results; *xN jhR]7v
} HDG"a&$
FQ&VM6_
public void setResults(List<E> results){ j{+I~|ZB,
this.results = results; H;}ue
} C2%3+
*m Tc4&*
public String toString(){ <5L` d}
StringBuilder buff = new StringBuilder JZ0+VB-3U
^rb7`s#G
(); R_&V.\e_
buff.append("{"); IZ ha* 7
buff.append("count:").append(count); T{2//$T?
buff.append(",p:").append(p); jtC ob'n8
buff.append(",nump:").append(num); <^$b1<@
buff.append(",results:").append ^*>no=A
=7Gi4X%
(results); fH{$LjH(
buff.append("}"); xo3)dsX
return buff.toString(); X7!A(q+h
} *VAi!3Rx;
i;
uM!d}
} ;Awzm )Q
;{u#~d}
\}(-9dr