Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 0_'(w;!wq:
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 4x7(50hp#
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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 },58B
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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 S_; 5mb+b
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分页支持类: tLCu7%P>
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java代码: qLrvKoEX2
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package com.javaeye.common.util; \f| Hk*@
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import java.util.List; tGt/=~n9
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publicclass PaginationSupport { ]xGo[:k|E
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publicfinalstaticint PAGESIZE = 30; *+(t2!yFmE
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privateint pageSize = PAGESIZE; lGrp^
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privateList items; |;xm-AM4r
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privateint totalCount; ZEY="pf
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privateint[] indexes = newint[0]; q5
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privateint startIndex = 0; YywiY).]@
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public PaginationSupport(List items, int 1B}q?8n
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totalCount){ 6cR}Mm9Hx3
setPageSize(PAGESIZE); 0IZaf%zYc
setTotalCount(totalCount); A:|dY^,:?*
setItems(items); c:#<g/-{wM
setStartIndex(0); t][U`1>i
} zED#+-7
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public PaginationSupport(List items, int L{`S^'P<
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totalCount, int startIndex){ U-RR>j
setPageSize(PAGESIZE); D5]AL5=Xt2
setTotalCount(totalCount); -64@}Ts*?
setItems(items); /<[S> ;!kr
setStartIndex(startIndex); &6]+a4
} ~K'e}<-G
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public PaginationSupport(List items, int 9Z?P/
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totalCount, int pageSize, int startIndex){ /#mq*kNIM6
setPageSize(pageSize); mCM7FFl I
setTotalCount(totalCount); b1+6I_u.
setItems(items); H~Z$ pk%
setStartIndex(startIndex); -NzO ,?
} DlC\sm
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publicList getItems(){ }"}
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return items; 'Cki"4%<
} $~>3bik@
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publicvoid setItems(List items){ hz:^3F`>/&
this.items = items; $'Pn(eZHGv
} 0!4;."S
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publicint getPageSize(){ '5^$v{
return pageSize; g/*x;d=
} m(2(Caz{
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publicvoid setPageSize(int pageSize){ 7JC^+rk
this.pageSize = pageSize; l>(w]
} )q.Z}_,)@
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publicint getTotalCount(){ ZD$W>'m{F
return totalCount; K&L9Ue
} NxOiT#YH
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publicvoid setTotalCount(int totalCount){ J#k3iE}
if(totalCount > 0){ '(ZJsw
this.totalCount = totalCount; ]V*ku%L0
int count = totalCount / Oup5LH!sW
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pageSize; qcN{p7=0
if(totalCount % pageSize > 0) ]lBe
count++; fj
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indexes = newint[count]; _:RQ9x'
for(int i = 0; i < count; i++){ >Q(+H-w
indexes = pageSize * ,(1n(FZ
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i; )7X+T'?%
} B: '}SA{
}else{ N3M:|D
this.totalCount = 0; ]YQ!i@Y
} [{s 1=c
} 4blw9x N
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publicint[] getIndexes(){ KOQiX?'
return indexes; UJ\[^/t
} ,]:vk|a#;
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publicvoid setIndexes(int[] indexes){ .2K4<UOAbm
this.indexes = indexes; ZQL4<fy'E
} B #[URZ9S
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publicint getStartIndex(){ N }$$<i2o
return startIndex; ym\AVRO{
} mbf'xGO
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publicvoid setStartIndex(int startIndex){ L9lN AiOH
if(totalCount <= 0) |*G$ilu
this.startIndex = 0; }Q }&3m~g
elseif(startIndex >= totalCount) 0XkLWl|k
this.startIndex = indexes S]Y3nI
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[indexes.length - 1]; {2A| F{7>
elseif(startIndex < 0) Vxr_2Kra
this.startIndex = 0; \(4"kY_=
else{ Dw%V.J/&o
this.startIndex = indexes 2
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[startIndex / pageSize]; '}nH\?(
} S.: m$s
} U@;W^Mt
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publicint getNextIndex(){ r Jo8|
int nextIndex = getStartIndex() + V`ODX>\
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pageSize; `6R.*hq
if(nextIndex >= totalCount) #
return getStartIndex(); 1 #zIAN>
else NWSm
return nextIndex; \d"uR@$3mG
} T[~8u9/
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publicint getPreviousIndex(){ G}2DZ=&>'
int previousIndex = getStartIndex() - QU#u5sX A
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pageSize; Z+gG.|"k
if(previousIndex < 0) '8k{\>
return0; QNN*/n
else 3?}\Hw
return previousIndex; ?g~w6|U(r
} v$WH#;(\
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} =XRTeIZ
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抽象业务类 Zb \E!>V
java代码: vU4Gw4
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/** _mEW]9Sp
* Created on 2005-7-12 he
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*/ z1K}] z%
package com.javaeye.common.business; JU6PBY~C'
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import java.io.Serializable; _,"?R]MO
import java.util.List; %2S+G?$M?
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import org.hibernate.Criteria; Y%OJ3B(n|
import org.hibernate.HibernateException; k@[P\(a3b
import org.hibernate.Session; %(P\"hE'
import org.hibernate.criterion.DetachedCriteria; -(Zi
import org.hibernate.criterion.Projections; #4yh-D"
import >`0l"K<
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org.springframework.orm.hibernate3.HibernateCallback; Iu)76Y@=5=
import M%3P@GRg
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org.springframework.orm.hibernate3.support.HibernateDaoS A89n^@
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upport; >*wF~G*k
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import com.javaeye.common.util.PaginationSupport; ~!Ar`=
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public abstract class AbstractManager extends Vgj&hdbd
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HibernateDaoSupport { un&Z'
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privateboolean cacheQueries = false; 'XbrO|%
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privateString queryCacheRegion; I6.!0.G
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publicvoid setCacheQueries(boolean 7\T~KYb?
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cacheQueries){ ].!^BYNht
this.cacheQueries = cacheQueries; eZck$]P(6H
} |riP*b
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publicvoid setQueryCacheRegion(String Miw*L;u@W
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queryCacheRegion){ ask76
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this.queryCacheRegion = x!i(M>P
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queryCacheRegion; 2w7PwNb*32
} DHnO ,"
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publicvoid save(finalObject entity){ +H4H$H
getHibernateTemplate().save(entity); N Dqvt$
} C4].egVg
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publicvoid persist(finalObject entity){ O^2@9
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getHibernateTemplate().save(entity); /uNgftj
} H}p5qW.tH:
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publicvoid update(finalObject entity){ 5gg
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getHibernateTemplate().update(entity); b@>MA
} 5;alq]m7
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publicvoid delete(finalObject entity){ !D \u2h
getHibernateTemplate().delete(entity); K:cZq3F
} P<OSm*;U:
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publicObject load(finalClass entity, Il8,g+W]
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finalSerializable id){ P@xb
return getHibernateTemplate().load \\D(St
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(entity, id); ?RMOy$L
} l$\OSG
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publicObject get(finalClass entity, Pw:{
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finalSerializable id){ Hd8 O3_5
return getHibernateTemplate().get eF06B'uL
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(entity, id); rZi\
} rYP72<
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publicList findAll(finalClass entity){ Ocp`6Fj
return getHibernateTemplate().find("from 6!;eJYj,
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" + entity.getName()); `p'(:W3a
} RP9jZRDbZ
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publicList findByNamedQuery(finalString JHvawFBN<u
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namedQuery){ ' ~F
return getHibernateTemplate q\r@x-&g+
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().findByNamedQuery(namedQuery); d OYEl<!J
} ->rr4xaK C
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publicList findByNamedQuery(finalString query, ..=WG@>$+
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finalObject parameter){ 2x<A7l)6
return getHibernateTemplate 937 z*mh
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().findByNamedQuery(query, parameter); 7%0V ?+]P
} |l#<vw
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publicList findByNamedQuery(finalString query, qrw"z
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finalObject[] parameters){ ~B2,edkM
return getHibernateTemplate ~w,c6Z
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().findByNamedQuery(query, parameters); 6A;,Ph2
} x&4gy%b
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publicList find(finalString query){ $[*QsU%%
return getHibernateTemplate().find hUo}n>Aa
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(query); @}oY6cW;B*
} .G~Y`0
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publicList find(finalString query, finalObject x[dR5
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parameter){ Zai:?%^
return getHibernateTemplate().find Gp.XTz#=
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(query, parameter); Q&k1' nT5
} -L6YLe%w
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public PaginationSupport findPageByCriteria &9ZrZ"]
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(final DetachedCriteria detachedCriteria){ U{[ g"_+~
return findPageByCriteria ^OZ*L e
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); >bUxb-8
} l =X6m(
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public PaginationSupport findPageByCriteria F39H@%R
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(final DetachedCriteria detachedCriteria, finalint IJQ"
*;
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startIndex){ nPRv.h
return findPageByCriteria xJ(}?0h-X
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(detachedCriteria, PaginationSupport.PAGESIZE, rFLm!J]
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startIndex); ^Q9;ro*;ck
} ~^ <1k-
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public PaginationSupport findPageByCriteria !$Whftg
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(final DetachedCriteria detachedCriteria, finalint 0tS<
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pageSize, =Y]'wb
finalint startIndex){ ,3P@5Ef
return(PaginationSupport) S9mcThcZ
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getHibernateTemplate().execute(new HibernateCallback(){ sn.0`Stt
publicObject doInHibernate lq_(au.
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(Session session)throws HibernateException { +aoenUm5
Criteria criteria = eR|u']Em>T
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detachedCriteria.getExecutableCriteria(session); ;QS(`SK l
int totalCount = -`s_md0BM
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((Integer) criteria.setProjection(Projections.rowCount !V~,aoKTj
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()).uniqueResult()).intValue(); /JGET
criteria.setProjection NfsF'v
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(null); /73ANQ"
List items = {4^NZTjd@
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criteria.setFirstResult(startIndex).setMaxResults F~Sw-b kSf
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(pageSize).list(); EpUBO}q]
PaginationSupport ps = K*sav?c
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new PaginationSupport(items, totalCount, pageSize, O =gv2e
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startIndex); GC3WB4iY@U
return ps; SCq:jI
} e anR$I;Yj
}, true);
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} VOkSR6
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public List findAllByCriteria(final I ]HP
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DetachedCriteria detachedCriteria){ )[np{eF.k
return(List) getHibernateTemplate {7Qj+e^
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().execute(new HibernateCallback(){ oU)Hco "_k
publicObject doInHibernate 5i1E
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(Session session)throws HibernateException { VBq|j"o0"
Criteria criteria = N_liKhq
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detachedCriteria.getExecutableCriteria(session); ttd
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return criteria.list(); aESlbH
} 2kkqPBc_
}, true); FnWN]9
} M;j)F
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public int getCountByCriteria(final uFYcVvbT@
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DetachedCriteria detachedCriteria){ y{g"w
Integer count = (Integer) wmDO^}>ZP
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getHibernateTemplate().execute(new HibernateCallback(){ +cwuj
publicObject doInHibernate ]9lR:V
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(Session session)throws HibernateException { PR3&LI;B*
Criteria criteria = PdqyNn=
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detachedCriteria.getExecutableCriteria(session); vJ9IDc|[
return /I48jO^2
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criteria.setProjection(Projections.rowCount _@@.VmZL
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()).uniqueResult(); 7fXta|eP0
} {v,NNKQ4x
}, true); bR'UhPs-8;
return count.intValue(); 3XSfXS{lwP
} Y|nC_7&Bv
} r?2J
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用户在web层构造查询条件detachedCriteria,和可选的 bc]SY =
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 C+%6N@
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PaginationSupport的实例ps。 NnRX 0]
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ps.getItems()得到已分页好的结果集 o0 |T<_
ps.getIndexes()得到分页索引的数组 tLzb*U8'1w
ps.getTotalCount()得到总结果数 E RjMe'q4
ps.getStartIndex()当前分页索引 p+#]Jr
ps.getNextIndex()下一页索引 2*5pjd{Kt
ps.getPreviousIndex()上一页索引 o@[oI\Vr!
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 {F ',e~}s
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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 ymb{rKkN3
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一下代码重构了。 x5R|,bY
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我把原本我的做法也提供出来供大家讨论吧: pEq }b+-
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首先,为了实现分页查询,我封装了一个Page类: ,t
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java代码: gX]ewbPDQ
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/*Created on 2005-4-14*/ gMs B1|
package org.flyware.util.page; Z '~Ie~
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/** c@Xb6 z_>
* @author Joa 5;X r0f
* .oqe0$I
*/ s)G?5Gz
publicclass Page { {ObUJ3
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/** imply if the page has previous page */ uxlrJ1~M
privateboolean hasPrePage; v}TFM
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/** imply if the page has next page */ dy]ZS<Hz8G
privateboolean hasNextPage; <72q^w
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/** the number of every page */ zy`T!
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privateint everyPage; r3dGXiu
) uTFId
/** the total page number */ '7
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privateint totalPage; Mc{-2
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/** the number of current page */ XD Q<28^
privateint currentPage; dP?QPky{9
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/** the begin index of the records by the current W<:x4gBa
<"yL(s^u"
query */ .'b|pd
privateint beginIndex; JnLF61
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/** The default constructor */ o37D~V;
public Page(){ zEt!Pug
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} B+z>$6
aSMoee@!
/** construct the page by everyPage hQeG#KQ
* @param everyPage Ax*xa6_2
* */ +F*h\4ry#
public Page(int everyPage){ og&-P=4O
this.everyPage = everyPage; SqZ .}s
} Qna*K7kv
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/** The whole constructor */ gv){&=9/
public Page(boolean hasPrePage, boolean hasNextPage, _'l"Dk
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int everyPage, int totalPage, 5\}E4y
int currentPage, int beginIndex){ qRHT~ta-?
this.hasPrePage = hasPrePage; 2I283%xr
this.hasNextPage = hasNextPage; mpQu:i|W
this.everyPage = everyPage; =1y~Qlu
this.totalPage = totalPage; dDa&:L
this.currentPage = currentPage; 0U8'dYf
this.beginIndex = beginIndex; 2"c 5<
} nl~Z,Y$
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/** &Q* 7
* @return Zv(6VVj
* Returns the beginIndex. Bru] ;%Qg%
*/ ^^F 8M0k3
publicint getBeginIndex(){ ]Y@_ 2`
return beginIndex; jVh:Bw
} WF:4p]0~)
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/** [^D>xD3B2
* @param beginIndex L1f=90
* The beginIndex to set. x_CY`Y
*/ MRg Ozg
publicvoid setBeginIndex(int beginIndex){ O[\mPFu5
this.beginIndex = beginIndex; #8~ygEa}
} KTBtLUH]*F
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/** (\o4 c0UzK
* @return =R "LB}>h}
* Returns the currentPage. P@D\5}*6
*/ a_-@rceU
publicint getCurrentPage(){ w|Ry)[
return currentPage; #M4LG; B
} 5~ZzQG
qOIVuzi*
/** ;NE4G;px4<
* @param currentPage `"hWbmQ
* The currentPage to set. 3Yo)K
*/ 5 D=r7
publicvoid setCurrentPage(int currentPage){ -9;?k{{[T
this.currentPage = currentPage; GFju:8P?
} (UCCEQq5
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/** |6;-P&_n
* @return q|0l>DPRp
* Returns the everyPage. K]uH7-YvL/
*/ ZH*h1?\X
publicint getEveryPage(){ zl|
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return everyPage; 62MQ+H
} wqT9m*VK
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/** [4aw*M1z}.
* @param everyPage Xvoz4'Gme
* The everyPage to set. 1Wiz0X/
*/ wS+!>Q_]w
publicvoid setEveryPage(int everyPage){ b- bvkPN
this.everyPage = everyPage; iSUu3Yv,_m
} UWhJkJsX
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/** ~ch%mI~
* @return 'Ebjn>"
* Returns the hasNextPage. &=kb>*
*/ }"SqB{5e(
publicboolean getHasNextPage(){ o';/$xrH
return hasNextPage; e ;^}@X
} @WJ\W `P
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/** ~mwIr
* @param hasNextPage QPh3(K1w^
* The hasNextPage to set. UvM4-M%2JN
*/ \WbQS#Z9
publicvoid setHasNextPage(boolean hasNextPage){ DycXJ3eQ
this.hasNextPage = hasNextPage; HVhP |+
} n>7aZ1Qa
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/** L[A?W
* @return %n GjP^
* Returns the hasPrePage. 8e^u KYR<
*/ 1e7I2g
publicboolean getHasPrePage(){ 8qaU[u&$
return hasPrePage; WUo\jm[yr
} 0
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/** KV$4}{
* @param hasPrePage Jp%5qBS^
* The hasPrePage to set. ^sFO[cYo
*/ *,%$l+\h
publicvoid setHasPrePage(boolean hasPrePage){ k`A39ln7wu
this.hasPrePage = hasPrePage; X,#~[%h$-=
} , ,ng]&%i
eV/oY1B]<
/** Dte5g),R
* @return Returns the totalPage. HyOrAv
<
* Jj\lF*B
*/ awvP;F?q|
publicint getTotalPage(){ @6UZC-M0
return totalPage; >T c\~l
} D4{KU%Xp&
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/** %[s%H)e)
* @param totalPage ?FjnG_Uz`D
* The totalPage to set. Wz"H.hf
*/ Kop(+]Q&n
publicvoid setTotalPage(int totalPage){ h3&|yS|
this.totalPage = totalPage; Crg'AB?
} ?w'86^_z
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} ,W|-?b?
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上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 'P" i9j
9=3DYCk/
个PageUtil,负责对Page对象进行构造: hV0fkQ.|
java代码: EG|dN(qh
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/*Created on 2005-4-14*/ noL9@It0
package org.flyware.util.page; s.Bb@Jq
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import org.apache.commons.logging.Log; ,7c Rd }1Y
import org.apache.commons.logging.LogFactory; wT6zeEV~*
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/** `]XI Q\ *
* @author Joa 7pciB}$2
* qt*+ D
*/ X!/Sk1
publicclass PageUtil { >5:O%zQ@
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privatestaticfinal Log logger = LogFactory.getLog :?BK A0E
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(PageUtil.class); Ez0zk9
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/** dpscgW{M
* Use the origin page to create a new page )7NI5x^$
* @param page $--+M
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* @param totalRecords 5B4/2q=
* @return X~c?C-fV
*/ %Q0R]
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publicstatic Page createPage(Page page, int i!e8-gVMP&
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totalRecords){ dzPewOre*
return createPage(page.getEveryPage(), 25-h5$s
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page.getCurrentPage(), totalRecords); AH5;6Q
} htR.p7&Tn
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/** u;-fG9xs
* the basic page utils not including exception xlu4
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handler \|HNFx T`
* @param everyPage O^row1D_
* @param currentPage lV%1I@[M
* @param totalRecords _W_< bI34
* @return page SeDk/}/~e
*/ ;%^=V#
publicstatic Page createPage(int everyPage, int HNv~ZAzBG-
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currentPage, int totalRecords){ @r/~Y]0Ye5
everyPage = getEveryPage(everyPage); qJrKt=CE
currentPage = getCurrentPage(currentPage); $=N?[h&4
int beginIndex = getBeginIndex(everyPage, /B~[,ES@1
J:glJ'4E
currentPage); ,r;xH}tbi
int totalPage = getTotalPage(everyPage, 6{HCF-cQd
u"*DI=pwb
totalRecords); Wu/#}Bw#
boolean hasNextPage = hasNextPage(currentPage, #IM.7`I
,:A;4
totalPage); S* O .
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boolean hasPrePage = hasPrePage(currentPage); 9tPRQM7
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returnnew Page(hasPrePage, hasNextPage, ChG7>4:\
everyPage, totalPage, vBl:&99[/
currentPage, pF8 #H~
\"nut7";2
beginIndex); o?hr>b
} p ZTrh&I]
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privatestaticint getEveryPage(int everyPage){ .E}lAd.Mn
return everyPage == 0 ? 10 : everyPage; I"vkfi#=
} X]D,kKasG
DI{*E
privatestaticint getCurrentPage(int currentPage){ ; s/<wx-C
return currentPage == 0 ? 1 : currentPage; 4$pV;xV
} +)"Rv%.
U\tx{CsSz
privatestaticint getBeginIndex(int everyPage, int l9&k!kF`
qrlC
U4
currentPage){ 9DNp
return(currentPage - 1) * everyPage; SI+Uq(k
} }QE*-GVv]
u/u(Z&
privatestaticint getTotalPage(int everyPage, int c Pf_B=
#6<1
=I'j
totalRecords){ OpEH4X.Z
int totalPage = 0; F. SB_S<'
j/d}B_2
if(totalRecords % everyPage == 0) Fds
11
/c7
totalPage = totalRecords / everyPage; =oq8SL?bJ*
else lt&(S)
totalPage = totalRecords / everyPage + 1 ; SULFAf<
daI_@k Y"
return totalPage; ^x: lB>
} *b.
>
nJ2x;';lA
privatestaticboolean hasPrePage(int currentPage){ P U/<7P*
return currentPage == 1 ? false : true; i#`q<+/q
} \H@1VgmR;
c_D(%Vf5
privatestaticboolean hasNextPage(int currentPage, _b~{/[s
aLGq<6Ja
int totalPage){ Lr$Mk#'B
return currentPage == totalPage || totalPage == {4G/HW28
K%? g6j
0 ? false : true; jfY7ich
} Ey|_e3Lf[
Qw}1q!89
TB!I
} -$Hu$Y}>
wgS,U}/i
F#sm^% _2
dWvVK("Wj
'|zrzU=
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 5FoZ$I
y(p_Unm
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 r[a7">n
"^n,(l*4x
做法如下: J{1H$[W~}
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 7~mhWPzMwB
7#0buXBg
的信息,和一个结果集List: sI!H=bp-8
java代码: &xQM!f
3c=kYcj
00QJ596
/*Created on 2005-6-13*/ =Xh)34q
package com.adt.bo; @i1e0;\
&Vz$0{d5
import java.util.List; 3S:Lce'f
:hX[8u
import org.flyware.util.page.Page; qq| 5[I.?
ukW&\
/** FQDf?d5
* @author Joa [X.bR$>
*/ Hsf::K x
publicclass Result { _s=H|#l
lD/9:@q\V
private Page page; J+u}uN@
v _MQ]X
private List content; !mmMAsd,
}'$PYAf6
/** KhHFJo[8sf
* The default constructor $')C&
*/ y2G Us&09
public Result(){ vjuFVJwL
super(); 50^ux:Uv+N
}
p+h$]CH
D(AH3`*|#
/** 6}"c4^k6
* The constructor using fields dI{DiPho
* ~|V^IJZ22
* @param page lM6pYYEq=
* @param content Gmz^vpQ]t
*/ 0@
Y#P|QF
public Result(Page page, List content){ AG N/kx
this.page = page; i+*!"/De
this.content = content; P=QxfX0B
}
9r!8BjA
%=`JWLLG
/** kJWg},-\
* @return Returns the content. 7>JTQ CJ
*/ d~LoHp
publicList getContent(){ h Jb2y`,q
return content; z%82Vt!a5
} 7zb^Z]
b dgkA
/** H@Z_P p?
* @return Returns the page. ;)(g$r^_i
*/ D@O`"2
public Page getPage(){ 4ba*Nc*Yc
return page; Z[oF4 z
} -K64J5|b7
2B
]q1>a!
/** oJ74Mra
* @param content z0[XI 7KK
* The content to set. O
*sU|jeO
*/ EhcJE;S)
public void setContent(List content){ `\kihNkJn3
this.content = content; a5D|#9
} G,u=ngZ]
R6+)&:Ab{R
/** q&3
;e4
* @param page 53HA6:Q[
* The page to set. >t+U`6xK
*/ u "[f\l
publicvoid setPage(Page page){ <^5!]8*O
this.page = page; z5E%*]
} (Rw<1q`,
} KGz Nj%
1/.BP
A~?M`L>B
,i2-
i\i%WiRl
2. 编写业务逻辑接口,并实现它(UserManager, cb}"giXQTB
t#k]K]
UserManagerImpl) Pq;OShU_
java代码: jm}CrqU
QJ|@Y(KV0
Ipp_}tl_
/*Created on 2005-7-15*/ R'>!1\?Iq
package com.adt.service; ON :t"z5
Bn}woyJdx
import net.sf.hibernate.HibernateException; \T7Mt|f:5
(jT)o,IW&
import org.flyware.util.page.Page; Y6` xb`
1EyN
|m|
import com.adt.bo.Result; k# [!; <
<LHhs<M'
/** l5[5Y6c>
* @author Joa 2Ez<Iw
*/ E9:@H;Gc
publicinterface UserManager { #[+# bw_6
]I?.1X5d0
public Result listUser(Page page)throws uO%0rKW
2|nm> 4
HibernateException; @N=vmtLP
l2D*b93
} bJ~H
DB'v7
Ij0
st-{xC#N#
mUYRioNj
ZT0\V
]!B
java代码: HI.*xkBXl&
66yw[,Y
-ss= c #
/*Created on 2005-7-15*/ USg"wJY
package com.adt.service.impl; acd[rjeT
GEBSUvM 7
import java.util.List; UcRP/LR%C
A_xC@$1e<
import net.sf.hibernate.HibernateException; #N|\7(#~u
OF-k7g7
import org.flyware.util.page.Page; ~tDYo)hH8
import org.flyware.util.page.PageUtil;
aJu&h2G
7sot?gF
import com.adt.bo.Result; jLAEHEs
import com.adt.dao.UserDAO; z0z@LA4k6@
import com.adt.exception.ObjectNotFoundException; Qb536RpcTY
import com.adt.service.UserManager; E&M(QX5
kSAVFzUS
/** XiUq#84Q
* @author Joa UP~28%>X
*/ `m,4#P-kj
publicclass UserManagerImpl implements UserManager { (MwRe?Ih
!~ox;I}S
private UserDAO userDAO; >3 o4 U2
6(n0{A
/** cgnNO&
* @param userDAO The userDAO to set. {}O~tf_
*/ P}R:o
publicvoid setUserDAO(UserDAO userDAO){ -ng1RA>
this.userDAO = userDAO; mRk)5{
} +QChD*
#:K=zV\
/* (non-Javadoc) F/5&:e?( )
* @see com.adt.service.UserManager#listUser :eN&wQ5q
tsXKhS;/w
(org.flyware.util.page.Page) ]aX@(3G1s
*/ $:9t(X)H
public Result listUser(Page page)throws c*bvZC^6
je] DR~
HibernateException, ObjectNotFoundException { '&IGdB I
int totalRecords = userDAO.getUserCount(); I"Oq< _
if(totalRecords == 0) oPe|Gfv\G
throw new ObjectNotFoundException x#1Fi$.
c~ss^[qx|
("userNotExist");
RD$:.
page = PageUtil.createPage(page, totalRecords); JZ5k3#@e
List users = userDAO.getUserByPage(page); N\{"&e
returnnew Result(page, users); O]N /(pe:d
} %a%xUce&-X
Y_Yf'z1>[
} X8C7d6ca
I)HO/i6>3
c -w #`
<BR^Dv07U
i%2u>Ni^
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 GVY7`k"km
Q,U0xGGz
询,接下来编写UserDAO的代码: DAn2Pqf
3. UserDAO 和 UserDAOImpl: GZ%vFje_
K
java代码: HC iRk1
V_7\VKR
{j2V k)\[i
/*Created on 2005-7-15*/ mLCDN1UO{
package com.adt.dao; }b_Ob
#QNN;&L]R
import java.util.List; [WwoGg*)mn
'l*X?ccKy
import org.flyware.util.page.Page; H& |/|\8F
\ .xS
import net.sf.hibernate.HibernateException; v~$V
wQxI({k@
/** 1@]&iZ]
* @author Joa )[rVg/m
*/ ^<I(
publicinterface UserDAO extends BaseDAO { >pq~ &)^u
@16GF!.
publicList getUserByName(String name)throws rN0<y4)!
sJ6.3=
c
HibernateException; F8pA)!AH
1lw%RM
publicint getUserCount()throws HibernateException; t"=5MaQk-
)+.=z
publicList getUserByPage(Page page)throws yRXML\Ge
mjeJoMvN)H
HibernateException; b3A0o*
-FZC|[is
} VD=H=Ju
O8]e(i
0Lo8pe`DH
.NOAp
HTQZIm
java代码: -WC0W
l=?e0d>O
4BCPh:
/*Created on 2005-7-15*/ 4@9Pd &I
package com.adt.dao.impl; +x]/W|5
[.#nM
import java.util.List; [ZWAXl
$
bzr2Zj{4
import org.flyware.util.page.Page; ]$smFF
'ZbWr*bo
import net.sf.hibernate.HibernateException; *HoRYCL
import net.sf.hibernate.Query; t2[/eM.G
\VpEUU6^U
import com.adt.dao.UserDAO; gAAC>{Wh
-S$F\%
/** 4H{t6t@-:
* @author Joa 7^dr[.Q[*
*/ tZ_'>7)
public class UserDAOImpl extends BaseDAOHibernateImpl ale'-V)5
gd;!1GNi]
implements UserDAO { #Oka7.yz
VN`.*B|9[
/* (non-Javadoc) 2KLMFI.F
* @see com.adt.dao.UserDAO#getUserByName ~I||"$R
@KQ>DBWQM
(java.lang.String) EI_-5Tt RD
*/ 1 Pk+zBJ$
publicList getUserByName(String name)throws mnm
ZO}
A`7(i'i5]
HibernateException { hRf
l\Q[
String querySentence = "FROM user in class ocGrB)7eD
dl4n-*h
com.adt.po.User WHERE user.name=:name"; DU^.5f
Query query = getSession().createQuery u*C*O4f>OC
$DHE%IN`
(querySentence); q5;dQ8Y?
query.setParameter("name", name); eHr0],
return query.list(); N/tcW
} E)-;sFz
7zu\tCWb
/* (non-Javadoc) ]8A*uyi
* @see com.adt.dao.UserDAO#getUserCount() `~XksyT
*/ }e\"VhAl/
publicint getUserCount()throws HibernateException { 2!#g\"
int count = 0; #^}H)>jWy
String querySentence = "SELECT count(*) FROM 'z|Da &d P
UoxlEec
user in class com.adt.po.User"; nxZz{&
Query query = getSession().createQuery C19N0=
A8-[EBkK
(querySentence); 8~Kq"wrbu
count = ((Integer)query.iterate().next e,%|sAs[
)7 57
()).intValue(); O#)1zD}
return count; AjK5x@\
} Ohm{m^VD"
8pnD6Lp>
/* (non-Javadoc) *w0!C:mL&
* @see com.adt.dao.UserDAO#getUserByPage +[76 _EXy
]IV{;{E)
(org.flyware.util.page.Page) wAHuPQ&_Q
*/ JSL&`
`
publicList getUserByPage(Page page)throws }#ink4dK:
@2E52$zu
HibernateException { )Cy>'l*Og7
String querySentence = "FROM user in class /a\i
jg]KE8(
com.adt.po.User"; 5}%R
Query query = getSession().createQuery 5zK,(cF0-
6kAAdy}ck
(querySentence); =@U5/J
query.setFirstResult(page.getBeginIndex()) OBWb0t5H?
.setMaxResults(page.getEveryPage()); 'I,a 29
return query.list(); +La2-I
} uE1;@Dm+
in>+D|q
c
} ,
>7PG2
a
L3b0e_8>R
<|r|s
}u8(7
uWJJ\
至此,一个完整的分页程序完成。前台的只需要调用 [/a
AH<9b
TtkHMPlm_
userManager.listUser(page)即可得到一个Page对象和结果集对象 ;"M6}5dQ4
~vXbh(MX
的综合体,而传入的参数page对象则可以由前台传入,如果用 8dR `T}
rl}<&aPH
webwork,甚至可以直接在配置文件中指定。 {0,b[
gvI!Ice#
下面给出一个webwork调用示例: d5^^h<'
java代码: p8'$@:M\
,:mL\ZED
f#z:ILG=
/*Created on 2005-6-17*/ b-ss^UL
package com.adt.action.user; ~cc }yDe
lp(2"$nQ
import java.util.List; Gwk$<6E
kWW2N0~$
import org.apache.commons.logging.Log; LDQ,SS,
import org.apache.commons.logging.LogFactory; ~u&gU1}
import org.flyware.util.page.Page; Erw1y,mF
sFM$O232
import com.adt.bo.Result; &|x7T<,)
import com.adt.service.UserService; \Y!#Y#c
import com.opensymphony.xwork.Action; cF
5|Pf
|$\K/]q-
/** 1["i,8zB
* @author Joa #@oB2%&X?
*/ VpJKH\)Rt(
publicclass ListUser implementsAction{ b? o
Y# }qXXZ>]
privatestaticfinal Log logger = LogFactory.getLog [gT}<W
JU17]gQ
(ListUser.class); iyn9[>je
h/ n(
private UserService userService; fG1iq<~
Z3&}C h
private Page page; wp@_4Iq1$
OKh0m_ )7
privateList users; +ydd"`
ah*{NR)
/* {dZ]+2Z~+
* (non-Javadoc) +(2$YJ35
* JuSS(dJw
* @see com.opensymphony.xwork.Action#execute() J$}]p
*/ <8}FsRr;J
publicString execute()throwsException{ eN<L)a:J_
Result result = userService.listUser(page); HQ@g6
page = result.getPage(); l/={aF7+
users = result.getContent(); D^4nT,&8
return SUCCESS; WO.u{vW]'
} VgVDTWs7
=p_*lC%N
/** TVcA%]y{;
* @return Returns the page. Nf([JP% 4
*/ <<!fA><W
public Page getPage(){ 'S3<' X
return page; 0g[ %)C
} +%YBa'Lk
&jqylX
/** #csP.z3^y
* @return Returns the users. Dnd; N/9
*/ Tc(=J7*r&
publicList getUsers(){ Dizz ?O
return users; %[|^7
} &:l-;7d
#_.JkY
/** |'z8>1
* @param page SAdT#0J
* The page to set. 2
`>a(
*/ BP9#}{kE
publicvoid setPage(Page page){ %rb$tKk
this.page = page; ~yJ 2@2I
} qt}M&=}8Q
(=^KP7
/** "jAd.x?X7e
* @param users qm$(_]R~`
* The users to set. $A?9U}V#^
*/ n1PptR
publicvoid setUsers(List users){ }sH[_%)
this.users = users; 3SIqod;%
} :V.@:x>id
U,P>P+\@
/** <-k!
* @param userService 9" q-Bb
* The userService to set. ^:-GPr
*/ T)gulP
publicvoid setUserService(UserService userService){ b;b,t0wS
this.userService = userService; >g<YH'U{
} *:yG)J 3F
} EQ273sdK
i*=~mO8E
R1H^CJ=v0
gl+d0<Rzw
Z jmQ
上面的代码似乎看不出什么地方设置了page的相关初值,事实上, /-p!|T}w
K#+?oFo:
可以通过配置文件来进行配置,例如,我想每页显示10条记录,那 {|u"I@M*O
^i%S}VK
么只需要: GS>[A b+
java代码: Ip'tB4Mq
]i#p2?BR
bqED5;d'#
<?xml version="1.0"?> nx'c=gp
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork KZjh<sjX|
~bZ=]i
1.0//EN" "http://www.opensymphony.com/xwork/xwork- ?:wb#k)Z/
gQr+~O
1.0.dtd"> r+ bGZ
-~{Z*1`,
<xwork> }R}+8
#Kb /tOp1
<package name="user" extends="webwork- >SI'Q7k
M,fL(b;2
interceptors"> _P.I+!w:x
%C_tBNE<
<!-- The default interceptor stack name LH4A!a]
a%r!55.
--> BI:Cm/ >
<default-interceptor-ref W q<t+E[
,Iyc0
name="myDefaultWebStack"/> .j:,WF<"l5
CI{2(.n4
<action name="listUser" S-Y{Vi"2
P{9:XSa%
class="com.adt.action.user.ListUser"> #r9+thyC
<param <(KCiM=E$
x{:U$[_
name="page.everyPage">10</param> wGti|7Tu*
<result C{bxPILw
&DMC\R* j
name="success">/user/user_list.jsp</result> FY'0?CT$
</action> Q~]oN
ARu_S
B
</package> s-IE}I?;
B!/kC)bF:
</xwork> =R=V
6nk}k]Ji
yq-~5ui
M>i(p%
tQ9%rb
R0=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 sYS
8]JU
.u)KP*_
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。 |Ml~Pmpp
r)|~Rs!y,
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 LWM<[8wJ4
T!H(Y4A
} [#8>T
XN<!.RCw
Z^V;B _
我写的一个用于分页的类,用了泛型了,hoho h*VDd3[#
j~N*T XkC
java代码: BsFO]F5mmX
"IU}>y>J
{P6Bfh7CZ
package com.intokr.util; %!\=$ s}g
5b:1+5iF-
import java.util.List; >\1twd{u]
E,m|E]WP
/** 1x_EAHZ>7
* 用于分页的类<br> U:*rlA@_.
* 可以用于传递查询的结果也可以用于传送查询的参数<br> :Vxt2@p{
* xq;>||B
* @version 0.01 fJ/INL
* @author cheng j9k:!|(2'
*/ STwGp<8
public class Paginator<E> { &MpLm&
privateint count = 0; // 总记录数 gg`{kN^r.a
privateint p = 1; // 页编号 pl>b 6 |
privateint num = 20; // 每页的记录数 OH>.N"IG
privateList<E> results = null; // 结果 tCrEcjT-
N 8[rWJ#
/** X}Q4;='C-
* 结果总数 g}hUCx(
*/ 1#x5
o2n
publicint getCount(){ %O9 Wm_%
return count; ~S('\h)1
} ) 'xyK
*R+M#l9D`
publicvoid setCount(int count){ 1<vJuF^
this.count = count; wxHd^b
} DPf].i#
cI[i v
/** gqv+|:#
* 本结果所在的页码,从1开始 IER;d\_V<
* G
T~rr*X
* @return Returns the pageNo. }`L;.9
*/ = -oP,$k
publicint getP(){ yr},pB
return p; p^Ey6,!8]D
} S!A:/(^WB
@2"uJ6o
/** Ct `)R
* if(p<=0) p=1 #v(As)4^
* DTC
IVLV
* @param p {qHQ_ _Bl
*/ YQD`4ND
publicvoid setP(int p){ )vq}$W!:9
if(p <= 0) HBp??.r
p = 1; _kBmKE
this.p = p; n}Z%-w$K#
} P\dfxR;8%
L<dh\5#p9Y
/** pbG-uH^
* 每页记录数量 N|mggz
*/ JPTLh{/
publicint getNum(){ %S^ke`MhF
return num; 5:38}p9`
} 7d.H8C2
$E[O}+L$#
/** s>L-0vG
* if(num<1) num=1 d1#lC*.Sg
*/ cWnEp';.
publicvoid setNum(int num){ y3(~8n
if(num < 1) rWWpP<
num = 1; z@UH[>^gj
this.num = num; @wD#+Oz
} O)^F z:
kR1
12J9P
/** ]foS.D,
* 获得总页数 ,sj(g/hg
*/ ?6*\M
publicint getPageNum(){ `%|3c
return(count - 1) / num + 1; 1?)h-aN
} .K^gh$z!
q>%.zc[x
/** rui 8x4c
* 获得本页的开始编号,为 (p-1)*num+1 BT(eU*m-
*/ ,r3`u2)
publicint getStart(){ MA{ZmPm)
return(p - 1) * num + 1; I[A<e]uK
} nEUH; z
>Ch2Ep
/** Zah<e6L
* @return Returns the results. %d:cC:`
*/ x%)oL:ue
publicList<E> getResults(){ UK'8cz9
return results; (Qw >P42J
} ,I|^d.[2
jKcl{',
public void setResults(List<E> results){ }`Wo(E}O
this.results = results; >G1]#'6;
} <b~~X`Z
;]R5:LbXS
public String toString(){ KKk<wya&O
StringBuilder buff = new StringBuilder Y A+R!t:F{
d?5oJ'JU
(); 2 .Xx)(>
buff.append("{"); 9[~.{{Y
buff.append("count:").append(count); PQi(Oc
buff.append(",p:").append(p); V,Bol(wY
buff.append(",nump:").append(num); a-#$T)mmfj
buff.append(",results:").append bOYM-\
{y
dM}c-=w`
(results); u=PLjrB~}
buff.append("}"); 8fQfu'LyjY
return buff.toString(); fM&
fqI
} ) F -8
Wt5pK[JV
} Z1$S(p=)L
&n?RKcH}d
q( EN]W],