Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 6iZ:0y0t+6
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 z/Kjz$l!
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据这一功能,我设计了通用的抽象Bean基类和分页类支持,代码来 3SMb#ce*o
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自于Quake Wang的javaeye-core包的相应类,然后又做了很多修改 G8Qo]E9-/
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分页支持类: XoZw8cY
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java代码: 1yg5d9
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package com.javaeye.common.util; dPtQ
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import java.util.List; AvxP0@.`
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publicclass PaginationSupport { +kXj+2
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publicfinalstaticint PAGESIZE = 30; EK
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privateint pageSize = PAGESIZE; OSDx
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privateList items; KXS{@/"-B
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privateint totalCount; IdzrQP
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privateint[] indexes = newint[0]; Y2B",v"
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privateint startIndex = 0; 2!y %nkO*
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public PaginationSupport(List items, int `H7V['
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totalCount){ \kQ@G
setPageSize(PAGESIZE); )HFl 0[vT
setTotalCount(totalCount); TfFuHzZZ
setItems(items); _Q
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setStartIndex(0); )}KQtkU8:
} \B$Q%\- PX
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public PaginationSupport(List items, int +~H mPQ
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totalCount, int startIndex){ 82q_"y>6
setPageSize(PAGESIZE); 5V($|3PI
setTotalCount(totalCount); FV1!IE-}-
setItems(items); [HV9KAoA
setStartIndex(startIndex); a BHV
} EXrOP]Kl
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public PaginationSupport(List items, int U_/<tWl\[3
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totalCount, int pageSize, int startIndex){
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setPageSize(pageSize); 2Y2J)5,
setTotalCount(totalCount); GkutS.2G#
setItems(items); 2Y+8!4^L
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setStartIndex(startIndex); FQ72VY
} >~% _U+6
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publicList getItems(){ HxgH*IMs
return items; =u+.o<
} N-+`[8@(P<
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publicvoid setItems(List items){ 5nhc|E)C
this.items = items; G#~6a%VW
} 3cp"UU}.
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publicint getPageSize(){ -c1$>+
return pageSize; v8<MAq
} ZV=)`E`I|
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publicvoid setPageSize(int pageSize){ @$ea-fK??
this.pageSize = pageSize; <XfCQq/
} 4*<27
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publicint getTotalCount(){ 1Xv- e8M
return totalCount; /^d!$v
} jq4{UW'
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publicvoid setTotalCount(int totalCount){ 9bDxml1
if(totalCount > 0){ 'yWv @)
this.totalCount = totalCount; Q>FuNdUk
int count = totalCount / L'>t:^QTh
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pageSize; |c]Y1WwDx
if(totalCount % pageSize > 0) /y\KLa
count++; Ff\U]g
indexes = newint[count]; 3j2% '$>E^
for(int i = 0; i < count; i++){ mxpncM=q
indexes = pageSize * ZA;wv+hF=
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} mh4NZ @;
}else{ #hBDOXHPf
this.totalCount = 0; qP"<vZ
} /FZ@Z]Q0G
} z]NN ^pIa
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publicint[] getIndexes(){ Ve4!MM@ti
return indexes; LZ@4,Uj
} SGU~LW&
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publicvoid setIndexes(int[] indexes){ ?1I0VA']
this.indexes = indexes; Mb I';Mq
} Tv;|K's'
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publicint getStartIndex(){ O?ZCX_R:L
return startIndex; !50Fue^JM
} r[:)-`]b
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publicvoid setStartIndex(int startIndex){ ?hu$
if(totalCount <= 0) %h ?c
this.startIndex = 0; j}=$2|}8{
elseif(startIndex >= totalCount) kpkN GQ2
this.startIndex = indexes mn=G6h
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[indexes.length - 1]; Jmln*,Ol7
elseif(startIndex < 0) h5bQ
this.startIndex = 0; Xm7Nr#
else{ HDyus5g
this.startIndex = indexes K4vl#*qn
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[startIndex / pageSize]; }5RCks;)*
} ,R
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}
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publicint getNextIndex(){ +G3&{#D
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int nextIndex = getStartIndex() + 1RtbQ{2F;
* Yr)>;^
pageSize; g`jO
if(nextIndex >= totalCount) ,$,6%"'"
return getStartIndex(); 29?{QJb
else /x6,"M[97
return nextIndex; NU*6MT4
} xj/ +Z!,9
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publicint getPreviousIndex(){ m~fA=#l
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int previousIndex = getStartIndex() - vZM.gn
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pageSize; zR'lQ<u
if(previousIndex < 0) ,y[wS5li
return0; /5@V $c8
else :QnN7&j|(w
return previousIndex; ?~e 8:/@
} Qa nE]
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} w.gI0`
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抽象业务类 j*m7&wOE
java代码: _MfB,CS
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/** VRYj&s'@
* Created on 2005-7-12 [N}:Di,S
*/ )5r *2I
package com.javaeye.common.business; ZM/*cA!"
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import java.io.Serializable; -X ~VXeg
import java.util.List; I3QK~ V*j)
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import org.hibernate.Criteria; nV-A0"z_&
import org.hibernate.HibernateException; 6,sZo!G
import org.hibernate.Session; /wB<1b"
import org.hibernate.criterion.DetachedCriteria; @,D 3$P8}
import org.hibernate.criterion.Projections; )W!8,e+%
import 8[SiIuIV
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org.springframework.orm.hibernate3.HibernateCallback; sO~:e?F
import vu[+UF\G
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org.springframework.orm.hibernate3.support.HibernateDaoS /sf:.TpVh
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upport; 'dYjbQ}~;
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import com.javaeye.common.util.PaginationSupport; i DV.L
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public abstract class AbstractManager extends \}Jy=[
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HibernateDaoSupport { k:nR'TI
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privateboolean cacheQueries = false; ^w.x~#zI
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privateString queryCacheRegion; |?n=~21"1O
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publicvoid setCacheQueries(boolean P 8DY*B k
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cacheQueries){ $\l7aA5~
this.cacheQueries = cacheQueries; TTaSg\K
} 6LRI~*F=3
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publicvoid setQueryCacheRegion(String V3fd]rIP
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queryCacheRegion){ p#W[he
this.queryCacheRegion = iha{(-
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queryCacheRegion; m5lMh14E
} RwMK%^b
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publicvoid save(finalObject entity){ {x e$
getHibernateTemplate().save(entity); W-:gU!{*#
} w?6"`Mo
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publicvoid persist(finalObject entity){ O^v^GG=e;C
getHibernateTemplate().save(entity); |Ui1Mm
} 4:-h\%
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publicvoid update(finalObject entity){ QLYb>8?"C
getHibernateTemplate().update(entity); bE
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} R9Wh/@J]
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publicvoid delete(finalObject entity){ _Z'j%/-4@D
getHibernateTemplate().delete(entity); })O^xF~
} W!pLk/|ls
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publicObject load(finalClass entity, w4U]lg<}E
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finalSerializable id){ ,Ju f
return getHibernateTemplate().load qepsR/0M
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(entity, id); EotZ$O=
} (#FWA<o
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publicObject get(finalClass entity, 2'_xg~
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finalSerializable id){ ri&B%AAc
return getHibernateTemplate().get 2bBTd@m4
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(entity, id); Cdl#LVqs
} %1fH-:c=C0
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publicList findAll(finalClass entity){ $lmbeW[0
return getHibernateTemplate().find("from )Q\nR`k
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" + entity.getName()); }Z*@EWc>
} +L1%mVq]y
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publicList findByNamedQuery(finalString hW[/{2<@
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namedQuery){ a9PSg/p
return getHibernateTemplate PVvNu5k
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().findByNamedQuery(namedQuery); bFk >IifN
} ,<*n>W4|
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publicList findByNamedQuery(finalString query, #4"(M9kf
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finalObject parameter){ ~TwjcI*/
return getHibernateTemplate tjc3;9
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().findByNamedQuery(query, parameter); hXdc5 ?i?
} _#xS1sD
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publicList findByNamedQuery(finalString query, S'qEBz
)p'ZSXb
finalObject[] parameters){ TB9{e!4
return getHibernateTemplate ,-^Grmr4M
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().findByNamedQuery(query, parameters); kx8\]'
} I*_@WoI*
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publicList find(finalString query){ WCT}OiLsL
return getHibernateTemplate().find VE5w!of
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(query); %cMX]U
} ?WE#%W7U
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publicList find(finalString query, finalObject E>f+ E8?
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parameter){ j+AAhn
return getHibernateTemplate().find n;8[WR)
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(query, parameter); fCTdM+t
} (&R/ns~
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public PaginationSupport findPageByCriteria 'PRsZ`x.
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(final DetachedCriteria detachedCriteria){ Y`jvza%
return findPageByCriteria $j*%}x~[
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); |k$^RU<OF
} FWI<_KZO
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public PaginationSupport findPageByCriteria x? 3U3\W
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(final DetachedCriteria detachedCriteria, finalint 8P5yaS_
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startIndex){ ||3%REliC
return findPageByCriteria !'uL
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(detachedCriteria, PaginationSupport.PAGESIZE, PjZsMHW%
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startIndex); ZaJg$
} mne4u W
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public PaginationSupport findPageByCriteria (c;F%m|
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(final DetachedCriteria detachedCriteria, finalint y<(q<V#0!S
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pageSize, 1'DD9d{qN
finalint startIndex){ _7es_w}R
return(PaginationSupport) 9x@( K|
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getHibernateTemplate().execute(new HibernateCallback(){ ?g
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publicObject doInHibernate GlkTpX^b
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(Session session)throws HibernateException { FJo?~
Criteria criteria = 8qGK"%{ ~
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detachedCriteria.getExecutableCriteria(session); "F?p\I)(
int totalCount = B M5+;h !
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((Integer) criteria.setProjection(Projections.rowCount S}6Ty2.\
)
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()).uniqueResult()).intValue(); t}L kl(
criteria.setProjection 4FURm@C6
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(null); . 4E5{F{~
List items = Q\.~cIw_AQ
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criteria.setFirstResult(startIndex).setMaxResults "SC }C
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(pageSize).list(); JDPn
PaginationSupport ps = V45A>#?U
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new PaginationSupport(items, totalCount, pageSize, ..BIoSrj
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startIndex); &?N1-?BjM
return ps; hG~4i:p
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} d-/{@
}, true); 3cfJ(%'X
} 4/UY*Us&
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public List findAllByCriteria(final (;DnL|"'8
lId}sf
DetachedCriteria detachedCriteria){ (jb9U k_t
return(List) getHibernateTemplate D5lzrpg _e
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().execute(new HibernateCallback(){ IoO t n
publicObject doInHibernate BfZAK0+*$
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(Session session)throws HibernateException { to9~l"n.s
Criteria criteria = E4;vC ?K{
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detachedCriteria.getExecutableCriteria(session); x!5b"
"
return criteria.list(); ;
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} SOE5`
}, true); 5cj]Y)I-~
} B(tLV9B3Q
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public int getCountByCriteria(final )F_vWbg
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DetachedCriteria detachedCriteria){ A^lJlr:_`
Integer count = (Integer) .*FBr7rE\
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getHibernateTemplate().execute(new HibernateCallback(){ NGQBOV
publicObject doInHibernate <ZmC8&Uo
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(Session session)throws HibernateException { 5cahbx1"
Criteria criteria = r'bctFsD
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detachedCriteria.getExecutableCriteria(session); \"=4)Huv
return dCq-&3?t
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criteria.setProjection(Projections.rowCount K"Vo'9R[_
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()).uniqueResult(); WcRTv"4&
} h8Wv t's
}, true); ^a+W!
return count.intValue(); MnToL@
} F)fCj^zL
} _:dt8+T#
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用户在web层构造查询条件detachedCriteria,和可选的 <'(O0
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 $z1W0
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PaginationSupport的实例ps。 GJTKqr|1O
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ps.getItems()得到已分页好的结果集 ~>2DA$Ec
ps.getIndexes()得到分页索引的数组 ?
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ps.getTotalCount()得到总结果数 X8(H#Ef[
ps.getStartIndex()当前分页索引 aTi2=HL=S
ps.getNextIndex()下一页索引 p7SX,kpt>
ps.getPreviousIndex()上一页索引 }jL_/gvgy
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 %w9/gD
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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 ?HD
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一下代码重构了。 KImBQ2 ^Tu
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我把原本我的做法也提供出来供大家讨论吧: XSfl'Fll D
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首先,为了实现分页查询,我封装了一个Page类: ~Qg:_ @@\
java代码: a"ct"g=
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/*Created on 2005-4-14*/ <[*%d~92z
package org.flyware.util.page; ,Z3 (`ftC
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/** f{i~hVF
* @author Joa 2Ra}&ie
* R=7,F6.
*/
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publicclass Page { Re[x$rw
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}
/** imply if the page has previous page */ Fa"/p_1
privateboolean hasPrePage; _%r +?I
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/** imply if the page has next page */ *|Bu 7nwg
privateboolean hasNextPage; to2#PXf]y
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/** the number of every page */ NE~R&ym9
privateint everyPage; HQ187IwpTm
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/** the total page number */ >]ghme
privateint totalPage; \`kH2`
h)NZG6R
/** the number of current page */ (u_?#PjX
privateint currentPage; XJ$mRh0`K
Z91{*?
/** the begin index of the records by the current ;nSOeAF)Q
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query */ \Fh#CI
privateint beginIndex; bmid;X|
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/** The default constructor */ z~m{'O`
public Page(){ Q
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l* ap$1'
} g+RgDt9
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/** construct the page by everyPage 9Z[EzKd<~'
* @param everyPage Y^Y1re+}
* */ w'r?)WW$
public Page(int everyPage){ av8\?xmo.$
this.everyPage = everyPage; ^ ,cwm:B@
} RV=Z$
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/** The whole constructor */ V7gv@<1<y
public Page(boolean hasPrePage, boolean hasNextPage, LvPcH
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int everyPage, int totalPage, %"jp':
int currentPage, int beginIndex){ [X&VxTxr
this.hasPrePage = hasPrePage; Lu][0+-
this.hasNextPage = hasNextPage; swTur
this.everyPage = everyPage; ,N1I\f
this.totalPage = totalPage; /0_^Z2
this.currentPage = currentPage; cWU9mzsE
this.beginIndex = beginIndex; *+UgrsRk
} E2nsBP=5C
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/** G u4mP
* @return nOQvBc
* Returns the beginIndex. m>:zwz< ;
*/ SDbR(oV
publicint getBeginIndex(){ Ovhd%qV;Y
return beginIndex; ]ZI ?U<0
} ^o8o
l ~C=yP(~
/** w=Yc(Y:h
* @param beginIndex uE=pq<
* The beginIndex to set. `zP{E T_Y
*/ 9 *+X^q'
publicvoid setBeginIndex(int beginIndex){ ~lQ<#*wl
this.beginIndex = beginIndex; tb1w 6jaU
} V4CL%i
AzZb0wW6p
/** q(XO_1W0V
* @return oro^'#ki
* Returns the currentPage. DkA@KS1Dq
*/ ,7/F?!G!J
publicint getCurrentPage(){ s#*
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return currentPage; `Ei:Z%@7C
} - %'ys
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/** .l:x!
* @param currentPage 45(n!"u65
* The currentPage to set. +?%LX4Y
*/ U{Xx)l/o
publicvoid setCurrentPage(int currentPage){ YVW`|'7)|
this.currentPage = currentPage; y?-zQs0
} .QLjaEja
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/** xsERn F>`
* @return XIRvIwO
* Returns the everyPage. mzbMX
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*/ K9=f`JI9
publicint getEveryPage(){ INF}~DN]
return everyPage; _qp^+
} VSDG_:!K
+d289"
/** ,&ld:v?~
* @param everyPage rk)h_zN
* The everyPage to set. -VafN
*/ \(4kEB2s$
publicvoid setEveryPage(int everyPage){ @\?QZX(H
this.everyPage = everyPage; "~,3gNTzV
} sIz*r Gz
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/** GS qt:<Qs
* @return V+>.Gf
* Returns the hasNextPage. pRc<U^Z.h
*/ C#oH7o+_.
publicboolean getHasNextPage(){ [eLU}4v{
return hasNextPage; Z` zyEP A
} 2 e9lk$
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/** Z~Vups#+f
* @param hasNextPage l|"SM6
* The hasNextPage to set. /DE`>eJY
*/ @A1Ohl
publicvoid setHasNextPage(boolean hasNextPage){ f2,\B6+
this.hasNextPage = hasNextPage; UC*\3:>'n
} l}&&f8n
zcCGREe=
/** oeA}b-Ct0
* @return Jf3xK"in
* Returns the hasPrePage. qu+Zl1~$]
*/ LQDU8[-
publicboolean getHasPrePage(){ S&z8-D=8k
return hasPrePage; bo_Tp~j
} ?@iGECll
) mh,F#"L
/** Nu4PY@m]C
* @param hasPrePage Kq&JvY^
* The hasPrePage to set. ?5Q_G1H&
*/ Br}0dha3E
publicvoid setHasPrePage(boolean hasPrePage){ :&\^r=D
this.hasPrePage = hasPrePage; iT,Ya-9"
} =&x
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/** Y<)9TU:D!
* @return Returns the totalPage. ~0T,_N
* $(N+E,XB
*/ wdLlQD
publicint getTotalPage(){ cIB[D.
return totalPage; -esq]c%3
} !+{$dB>a
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/** 0oNy
* @param totalPage bVW2Tjc:
* The totalPage to set. oBI@.&tG}
*/ GSa U:A
publicvoid setTotalPage(int totalPage){ ~(Xzm
this.totalPage = totalPage; 5o2vj8::
} hw)#TEt
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} p)YI8nW
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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 NKRI|'Y,
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个PageUtil,负责对Page对象进行构造: $G D@e0
java代码: du_TiI
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/*Created on 2005-4-14*/ i_ z4;%#?
package org.flyware.util.page;
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import org.apache.commons.logging.Log; nf)y_5y
import org.apache.commons.logging.LogFactory; p$!Q?&AV/
P> [,,w
/** c^W \0
* @author Joa 6sz:rv}
* c]>LL(R-7)
*/ #8sv*8&
publicclass PageUtil { 1qN+AT
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privatestaticfinal Log logger = LogFactory.getLog k:*(..!0z
iVAAGZ>am
(PageUtil.class); GQ])y
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/** :7 OhplI
* Use the origin page to create a new page Rt3/dw(p
* @param page #J|DW C!#d
* @param totalRecords !rPU5y*
* @return jQ&82X%m
*/ "e@?^J)
publicstatic Page createPage(Page page, int VB&`g<
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totalRecords){ xQ~N1Y2W
return createPage(page.getEveryPage(), 4>}qdR1L4
q&d5V~q
page.getCurrentPage(), totalRecords); R~! md
} NjP7?nXSx
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/** [a!*m<
* the basic page utils not including exception z!>ml3
Rr"D)|Y;C(
handler *z6m644H
* @param everyPage $4u8"n e)
* @param currentPage }&Kl)2:O
* @param totalRecords rJUXIV>z
* @return page Io\tZXB
*/ CaqqH`/E4
publicstatic Page createPage(int everyPage, int X(dHhO
94b*
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currentPage, int totalRecords){ {~{</ g/
everyPage = getEveryPage(everyPage); C)R#Om
currentPage = getCurrentPage(currentPage); P?$Iht.^
int beginIndex = getBeginIndex(everyPage, EU4j'1!&g<
O#3PUuE%d
currentPage); f0]`TjY
int totalPage = getTotalPage(everyPage, r0j+P%
' T%70)CM~
totalRecords); Ot([5/K
boolean hasNextPage = hasNextPage(currentPage, tr-muhuK
x
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totalPage); Eq6.
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boolean hasPrePage = hasPrePage(currentPage); D9;s%
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returnnew Page(hasPrePage, hasNextPage, GjeRp|_Qd<
everyPage, totalPage, VK3e(7b
currentPage, Yu_`
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beginIndex); i8i~b8r]
} O~&j}WN
q^^&nz<A
privatestaticint getEveryPage(int everyPage){ `VD7VX,rp*
return everyPage == 0 ? 10 : everyPage; l$DQkbOj
} R~H +.Vh
\Ws$@J-M
privatestaticint getCurrentPage(int currentPage){ -$tf`
return currentPage == 0 ? 1 : currentPage; UMj8<Lq)j
} o6c>sh
&7L g)PG
privatestaticint getBeginIndex(int everyPage, int NK$BF(HBi
H#FH'@J
currentPage){ \oy8)o/Gb
return(currentPage - 1) * everyPage; l$J2|\M6
} xF])NZy|
}e0>Uk`[
privatestaticint getTotalPage(int everyPage, int 66Bx,]"6
h7cE"m
totalRecords){ 2R>!Wj'G+o
int totalPage = 0; @@} ]qT*
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if(totalRecords % everyPage == 0) @r9[&
totalPage = totalRecords / everyPage; GRj#1OqL
else IXof-I%8
totalPage = totalRecords / everyPage + 1 ; 08F~6e6a8
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return totalPage; tde&w=ec
} F%`O$uXA
TDZ p1zpXb
privatestaticboolean hasPrePage(int currentPage){ DA9f\q
return currentPage == 1 ? false : true; /{FSG!
} 35Cm>X
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privatestaticboolean hasNextPage(int currentPage, [['
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rkWiGiisM
int totalPage){ ^Q5advxuq
return currentPage == totalPage || totalPage == 8 GW0w
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0 ? false : true; hL}AgY@
} z\+Ug9Of
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} prO ~g
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j+NsNIJq
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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。 3fdqFJ O
bo40s9"-*W
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 CQ/ps,~M
\CVrLn;}
做法如下: ~__rI-/_
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 ).8NZ
Aj
!(#d7R
的信息,和一个结果集List: _<6B.{$\7m
java代码: `=19iAp.
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<P0&!yN
/*Created on 2005-6-13*/ $_Q]3"U
package com.adt.bo; a|kEza,]
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import java.util.List; }Wz[ox 9b
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import org.flyware.util.page.Page; $n_ax\15
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/** \fJ _,
* @author Joa ]!v\whZ>
*/ E3QyiW
publicclass Result { d~z%kl
5:
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private Page page; %z"n}|%!
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private List content; @H61^K<
7;$[s6$
/** %&pd`A/
* The default constructor $<F9;Z
*/ I
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public Result(){ m\@ q2l-
super(); .RN2os{
} L&G5 kY`
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/** `P?!2\/
* The constructor using fields R/Te;z
* k]~|!`
* @param page 37 d-!
* @param content +
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*/ }E#1Z\)
public Result(Page page, List content){ g^[BnP)I
this.page = page; 3.w &e0Es
this.content = content; >8%O;3-m#
} |G(I,EPag
"J>8ZUP
/** OpLUmn
* @return Returns the content. ,nSapmg
*/ yt#~n_
publicList getContent(){ 9"f
return content; gzEcdDD
} ~=gpn|@b
g96]>]A<{
/** F&$~]R=&
* @return Returns the page. /TY=ig1z
*/ /dwj:g0y
public Page getPage(){ >(C5&3^
return page; G!E1N(%o
} ,$bK)|pGV
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/** A9o"L.o)
* @param content ub]"b[j\1
* The content to set. iHlee=}od
*/ {\55\e/C,
public void setContent(List content){ aPm2\Sq$
this.content = content; O:jaA3
} gb}>x O
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/** csj4?]gI
* @param page )}1S
`*J/O
* The page to set. Y InPmR
*/ 1;JH0~403
publicvoid setPage(Page page){ jS4fANG
this.page = page; J=Hyoz+9
} ^b6yN\,S
} *}=z^;_oq
>j)y7DSE
M i047-% (
x,UP7=6
V=)' CCi{
2. 编写业务逻辑接口,并实现它(UserManager, /A93mY[
*Ke\Yb
UserManagerImpl) Uf#9y182*c
java代码: 9YY*)5eyD
M?QX'fia
O6n]l
/*Created on 2005-7-15*/ Xd5uF/w
package com.adt.service; M`H@
% M
tC\(H=ecP
import net.sf.hibernate.HibernateException; !YIW8SP)
H0-v^H>^
import org.flyware.util.page.Page; La
r9}nx0
SHRn$<
import com.adt.bo.Result; Xp0S
6-QcHJ>m6U
/** r=S,/N(1
* @author Joa g)nT]+&
*/ 3c[]P2Bh
publicinterface UserManager { ,D2nUk
+ lZvj=gW
public Result listUser(Page page)throws $lb$ <
KN".0WU
HibernateException; Bb.U4#
t>h:s3c
} o_n 3.O=
GuKiNYI_
` NCH^)
i= jYl
@.} @K
java代码: m.Ki4NUm
t^"8
v3'h
Z ty9O8g
/*Created on 2005-7-15*/ 23/;W|
package com.adt.service.impl; sE! $3|Q
HM &"2c
import java.util.List; 3|=L1Pw#
@0-vf>e3-
import net.sf.hibernate.HibernateException; F"0=r
0}N"L ml
import org.flyware.util.page.Page; sf8F h
import org.flyware.util.page.PageUtil; .qs5xGg#9
$^`@ lyr
import com.adt.bo.Result; P.-
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import com.adt.dao.UserDAO; (: @7IWZf@
import com.adt.exception.ObjectNotFoundException; +!$]a^3l
import com.adt.service.UserManager; "~L$oji
dz1kQzOU*
/** ))4RgS$
* @author Joa Wv]ODEd
*/ 5IfC8drAs
publicclass UserManagerImpl implements UserManager { zoZ10?ojC
UdcrX`^.
private UserDAO userDAO; ##nC@h@
yaYJmhG
/** xc,Wm/[
* @param userDAO The userDAO to set. J$i.^|hE/
*/ GezMqt;2
publicvoid setUserDAO(UserDAO userDAO){ 7yUX]95y8
this.userDAO = userDAO; .+&M,%
x
} yaPx=^&
t"P:}ps{?
/* (non-Javadoc) $'3'[Nr(;t
* @see com.adt.service.UserManager#listUser v(p<88.!m
A~H@0>1
(org.flyware.util.page.Page) }!N/?A5
*/ ;*cCaB0u
public Result listUser(Page page)throws FT\%=>{
"6gBbm
HibernateException, ObjectNotFoundException { p\DSFB
int totalRecords = userDAO.getUserCount(); D+y?KihE
if(totalRecords == 0) J@+b_e*
throw new ObjectNotFoundException +mC?.B2D
DA>TT~L
("userNotExist"); avW33owb@
page = PageUtil.createPage(page, totalRecords); CI=M0
List users = userDAO.getUserByPage(page); ^.c<b_(=h
returnnew Result(page, users); *gOUpbtXa
} NRazI_Z
(Ta (Y=!uq
} Wpc8T="q
%:Z_~7ZR
yw >Frb5p
i5SDy(?r
_pxurq{
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 l OiZ2_2
J~AmRo0!k
询,接下来编写UserDAO的代码: KBa0
3. UserDAO 和 UserDAOImpl: d;i@9+
java代码: & l0LW,Bx
$hy0U_}6
b8!
/*Created on 2005-7-15*/ +v<
\l=
package com.adt.dao; Z=oGyA
vbfQy2q
import java.util.List; Z1{>"o:@
5YYBX\MV
import org.flyware.util.page.Page; `%*`rtZ+H.
a|z@5r%
import net.sf.hibernate.HibernateException; mDO! o
|)S*RQb\
/** .R)uk
* @author Joa 51;[R8'w
*/ ~SS3gL v
publicinterface UserDAO extends BaseDAO { q@1xYz:J
B+MnT{
publicList getUserByName(String name)throws KxDp+]N]
AWd,qldv
HibernateException; Cv[1HO<
nPk&/H%5hn
publicint getUserCount()throws HibernateException; +'wO:E1( w
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publicList getUserByPage(Page page)throws PJ\k|
bnJ4Edy
HibernateException; 7&u$^c S(
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} !|8"}ZF
&@=W+A=c~
#7@p
[S9"' ^H
3i~X`@$k>
java代码: L3A2A
H4$f+
NryOdt tI
/*Created on 2005-7-15*/ jB`:(5%RO
package com.adt.dao.impl; MaPI<kYQv
Hp@Q
import java.util.List; u<4bOJn({
T3I{D@+0
import org.flyware.util.page.Page; BN~ndWRK
RFX{]bQp9
import net.sf.hibernate.HibernateException; !(gSXe)*
import net.sf.hibernate.Query; O{0it6
e^;%w#tEqI
import com.adt.dao.UserDAO; P3nBxw"
r AE5.Q!u
/** |a%Wd
* @author Joa hzT)5'_
*/ F|@\IVEB]
public class UserDAOImpl extends BaseDAOHibernateImpl Wg2 0H23XW
'.C#"nY>1
implements UserDAO { UuC-R)
=2}V=E/85
/* (non-Javadoc) zRbY]dW
* @see com.adt.dao.UserDAO#getUserByName z#1"0Ks&P
20}w.V
(java.lang.String) sPXjU5uq#
*/ }9&dY!h +
publicList getUserByName(String name)throws nxNHf3
1}Y3|QxF
HibernateException { %0 i)l|
String querySentence = "FROM user in class /4@
[^}x
z:Z-2WV2o
com.adt.po.User WHERE user.name=:name"; SlwQ_F"4L
Query query = getSession().createQuery JW)f'r_f
/nn~&OU
(querySentence); Cc;8+Z=a?G
query.setParameter("name", name); X yiaRW
return query.list(); ]k'^yc{5
} `5!AHQ/
fI1
9p Q
/* (non-Javadoc) H8g%h}6h
* @see com.adt.dao.UserDAO#getUserCount() 6P:fM Y
*/ (.X)=
publicint getUserCount()throws HibernateException { 1b86@f
int count = 0; ^bP`Iv
String querySentence = "SELECT count(*) FROM y#th&YC_b
1z4_QZZ.NG
user in class com.adt.po.User"; -y{(h%6
Query query = getSession().createQuery pb)kN%
gS8+S\2
(querySentence); *,IK4F6>:
count = ((Integer)query.iterate().next - Ry+WS=
EB*C;ms
()).intValue(); &AWrM{e
return count; *")*w> R
} A=IpP}7J
esj6=Gh
/* (non-Javadoc) 2pU'&8
* @see com.adt.dao.UserDAO#getUserByPage DR,7rT{$
5-y*]:g(
(org.flyware.util.page.Page) h(<>s#=E
*/ {+nf&5E 6
publicList getUserByPage(Page page)throws 3W]gn8
f*xr0l
HibernateException { :0QDV~bs
String querySentence = "FROM user in class T\g+w\N
'nBP%
com.adt.po.User"; vZ811U~}
Query query = getSession().createQuery :~#)Xa0I
W]bgWKd
(querySentence); 9[;da
query.setFirstResult(page.getBeginIndex()) }WaZ+Mdg\
.setMaxResults(page.getEveryPage()); "qd|!:bE
return query.list(); gPb.%^p
} >3@3~F%xAX
EwkSUA>Tm
} ^+v1[U@
ZWo~!Z [Y
GZ,MC?W
=B5{ 7g\
1dw{:X=j
至此,一个完整的分页程序完成。前台的只需要调用 MfHOn YV
6@t&
userManager.listUser(page)即可得到一个Page对象和结果集对象 2QM{e!9
FO%pdLs,
的综合体,而传入的参数page对象则可以由前台传入,如果用 s\pukpf@
p6K ~b
webwork,甚至可以直接在配置文件中指定。 euVDrJ^
C\~}ySQc.e
下面给出一个webwork调用示例: yCav;ZS_
java代码: `lWGwFg g(
I`H&b&
.`
8V 4e\q
/*Created on 2005-6-17*/ xPPA8~Dm*
package com.adt.action.user; _#NibW
iC/*d
import java.util.List; 6lv@4R^u
u}|v;:|j
import org.apache.commons.logging.Log; #v<`|_
import org.apache.commons.logging.LogFactory; "YY<T&n
import org.flyware.util.page.Page; Yj/o17
6]~/`6Dub
import com.adt.bo.Result; \Ta5c31S+
import com.adt.service.UserService; PJ0~ymE1~G
import com.opensymphony.xwork.Action; ]% HxzJ
FHw%ynC
/** Mms|jFoQ
* @author Joa
vxTn
*/ _:=\h5}8
publicclass ListUser implementsAction{ ;Vs2e
pu]U_Ll@
privatestaticfinal Log logger = LogFactory.getLog wbrOL(q.m
hxH6Ii]\
(ListUser.class); $qz{L~ <
iD G&