Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 PN0l#[{EN
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 Zcd!y9]#
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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 U+sAEN_e k
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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 pK O\tkMJ
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分页支持类: ?}^e,.M0?s
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java代码: u>:sXm
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package com.javaeye.common.util; .(Q3M0.D
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import java.util.List; '/
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publicclass PaginationSupport { UMUr"-l =
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publicfinalstaticint PAGESIZE = 30; B]]_rl,
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privateint pageSize = PAGESIZE; <x DD*u
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privateList items; l<)(iU
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privateint totalCount; Fs_V3i3|L
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privateint[] indexes = newint[0]; q.i@Lvu#
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privateint startIndex = 0; ?1}1uJMj-
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public PaginationSupport(List items, int 69(z[opW
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totalCount){ csT_!sII
setPageSize(PAGESIZE); [(}f3W &
setTotalCount(totalCount); _={*<E
setItems(items); (.7_`T6QG
setStartIndex(0); q5:-?|jXJ
} ,6PV"E)_
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public PaginationSupport(List items, int 0wXfu"E{
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totalCount, int startIndex){ `7}6
setPageSize(PAGESIZE); K)$.0S9d
setTotalCount(totalCount); !cT#G
setItems(items); \\
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setStartIndex(startIndex); K$(&Qx}
} IJO`"da
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public PaginationSupport(List items, int hJ#U;GL
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totalCount, int pageSize, int startIndex){ sIdo(`8$
setPageSize(pageSize); [ivz/r(Rj
setTotalCount(totalCount); A_T-]YQ
setItems(items); "Q'#V!
setStartIndex(startIndex); Y'S xehx
} =PAvPj&}e
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publicList getItems(){ W&}YMb
return items; Hkg^
} =1)yI>2e%}
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publicvoid setItems(List items){ (qlIQC
this.items = items; hE-`N,i}
} 4?g~GI3
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publicint getPageSize(){ j{>E.F2.
return pageSize; n'7 3DApW
} REB8_ H"
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publicvoid setPageSize(int pageSize){ -'3vQXj&
this.pageSize = pageSize; 3X*;.'#Z
} W!.UMmw`
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publicint getTotalCount(){ {o+aEMhM
return totalCount; cQzd0X
} 26>e0hBh&
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publicvoid setTotalCount(int totalCount){ je9[S_Z:Y
if(totalCount > 0){ qi`*4cas*A
this.totalCount = totalCount; ii2X7Q
int count = totalCount / ,AGK O,w
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pageSize; MA.1t
if(totalCount % pageSize > 0) F0o7XUt
count++; r.xGvo{iY
indexes = newint[count]; 99G/(Z}
for(int i = 0; i < count; i++){ m@.4Wrv
indexes = pageSize * (k6=o';y
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} ?{\8!_Gvsl
}else{ *W y0hnr;]
this.totalCount = 0; /$\yAOA'y
} [esjR`u
} PDREwBX
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publicint[] getIndexes(){ 0@C`QW%m
return indexes;
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} 3T# zxu
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publicvoid setIndexes(int[] indexes){ [
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this.indexes = indexes; Ik>sd@X*|
} (:,N?bg
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publicint getStartIndex(){ fxI>FhU_
return startIndex; h\Op|#gIT
} d~g
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publicvoid setStartIndex(int startIndex){ $Etf'.
if(totalCount <= 0) kMo;<Z
this.startIndex = 0; MkC25
elseif(startIndex >= totalCount) igOjlg_Q
this.startIndex = indexes LV0g *ng
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[indexes.length - 1]; IxYuJpi
elseif(startIndex < 0) p !AQ
this.startIndex = 0; Za jQ B
else{ &1F)/$,v
this.startIndex = indexes NVS U)#
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[startIndex / pageSize]; LZ|G" 5X[
} x7L$x=8s
} )U>q><
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publicint getNextIndex(){ Iu2RK
int nextIndex = getStartIndex() + -/~^S]
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pageSize; 2xni! *T+
if(nextIndex >= totalCount) tJUMLn?
return getStartIndex(); ZJP.-` U
else !
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return nextIndex; W+H27qsv
} !z{bqPlFGG
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publicint getPreviousIndex(){ /6gqpzum4
int previousIndex = getStartIndex() - W`eYd|+C
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pageSize; 3.Ni%FF`
if(previousIndex < 0) F{[2|u(4
return0; Vd)iv\a
else A0oC*/
return previousIndex; !!o69
} _t:rWC"X
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} H6/@loO!Xy
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抽象业务类 VMad ]bEf
java代码: bNevHKS
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/** @-kzSm
* Created on 2005-7-12 6b-d#H/1Y
*/ !b rN)b)f
package com.javaeye.common.business; 8$v17 3
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import java.io.Serializable; $Fc*^8$ryC
import java.util.List; Rk"VFe>r
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import org.hibernate.Criteria; 67 7p9{:
import org.hibernate.HibernateException; x@v,qF$K
import org.hibernate.Session; yeE_1C .
import org.hibernate.criterion.DetachedCriteria; Q7"KgqpQ3
import org.hibernate.criterion.Projections; &KbtW_
import un W{ZfEC
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org.springframework.orm.hibernate3.HibernateCallback; a}M7"v9
import 1
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org.springframework.orm.hibernate3.support.HibernateDaoS NvJu)gI%
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upport; ]'~'V2Ey
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import com.javaeye.common.util.PaginationSupport; EVgn^,
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public abstract class AbstractManager extends duXv
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HibernateDaoSupport { 6}C4 SZ
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privateboolean cacheQueries = false; ?tqTG2! (
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privateString queryCacheRegion; v{Zh!mk* L
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publicvoid setCacheQueries(boolean %j2YCV7
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cacheQueries){ $'L(}gNv5
this.cacheQueries = cacheQueries; #q==GT7
} D*vrQ9
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publicvoid setQueryCacheRegion(String Vfg144FG'
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queryCacheRegion){ =<`9T_S 16
this.queryCacheRegion = ;?= ] ffa{
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queryCacheRegion; U
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} k/?+jb
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publicvoid save(finalObject entity){ Fd5{ pM3
getHibernateTemplate().save(entity); UgSSZ05Lq
} b]4yFwb
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publicvoid persist(finalObject entity){ #96E^%:zL
getHibernateTemplate().save(entity); fcnbPO0M
} >/1.VT\E
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publicvoid update(finalObject entity){ lsJ'dS
getHibernateTemplate().update(entity); q6H90Zb
} "* %=k%'
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publicvoid delete(finalObject entity){ NkNw9?:#4
getHibernateTemplate().delete(entity); 9g^@dfBV
} 9Hlu%R
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publicObject load(finalClass entity, d?b2jZ$r]
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finalSerializable id){ sw{EV0&>m
return getHibernateTemplate().load RX?Nv4-
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(entity, id); ;\4}Hcg
} UupQ*,dJ
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publicObject get(finalClass entity, <JF78MD\
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finalSerializable id){ akJ{-
return getHibernateTemplate().get cO)GiWE
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(entity, id); 8Nc i1o
} UO<uG#FB
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publicList findAll(finalClass entity){ ]$0{PBndW
return getHibernateTemplate().find("from ;S,g&%N
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" + entity.getName()); Zu&trxnNf[
} )z7.S"U
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publicList findByNamedQuery(finalString -7m;rD4J
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namedQuery){ N;r,B
return getHibernateTemplate -aKk#fd
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().findByNamedQuery(namedQuery); -s:JD J*
} PM%./
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publicList findByNamedQuery(finalString query, IGu*#>h
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finalObject parameter){ 47$JN}qI0
return getHibernateTemplate Og30&a!~F
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().findByNamedQuery(query, parameter); )TRDM[u
} %4n=qK9T5
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publicList findByNamedQuery(finalString query, #?}Y~Oe
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finalObject[] parameters){ {nj\dU
return getHibernateTemplate BtU,1`El5
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().findByNamedQuery(query, parameters); !X[lNtO
} "GZhr[AW
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publicList find(finalString query){ wx<5*8zP
return getHibernateTemplate().find Y`lC4*g
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(query); /SN.M6~
} 63:ZDQ
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publicList find(finalString query, finalObject E.6^~'/
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parameter){ @["Vzg!I6"
return getHibernateTemplate().find k`\DC\0RG
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(query, parameter); FUq@
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} i 3(bg,
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public PaginationSupport findPageByCriteria y1k""75
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(final DetachedCriteria detachedCriteria){ b%|%Rek8
return findPageByCriteria o^DiIoor
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); U
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} (qB$I\
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public PaginationSupport findPageByCriteria HC!$Z`}Y
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(final DetachedCriteria detachedCriteria, finalint w ="I*7c@
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startIndex){ O- r"G
return findPageByCriteria K
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(detachedCriteria, PaginationSupport.PAGESIZE, `'
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startIndex); m"+9[d_u
} NUx%zY
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public PaginationSupport findPageByCriteria WOgbz&S?J
A"S})
(final DetachedCriteria detachedCriteria, finalint 8 wC3}U
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pageSize, b.ow0WYe
finalint startIndex){ jsi\*5=9p<
return(PaginationSupport) =b9?r
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getHibernateTemplate().execute(new HibernateCallback(){ \>9%=32u.
publicObject doInHibernate lBPZB%
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(Session session)throws HibernateException { wl5!f|
Criteria criteria = *K m%Vl
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detachedCriteria.getExecutableCriteria(session); rxm!'.+
int totalCount = pD`7N<F 3
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((Integer) criteria.setProjection(Projections.rowCount HjV83S;
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()).uniqueResult()).intValue(); M}M.
criteria.setProjection WR~uy|mX
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(null); ]6$NU
[
List items = yrkd#m
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criteria.setFirstResult(startIndex).setMaxResults #7gOtP#{
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(pageSize).list(); JJ7-$h'0q
PaginationSupport ps = ~Bj-n6 QDE
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new PaginationSupport(items, totalCount, pageSize, d \0K3=h
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startIndex); Rn-L:o@?
return ps; :
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} Ig5J_Z^]b
}, true); o+6Y/6Xp@
} #4d0/28b
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public List findAllByCriteria(final F"a,[i,[W
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DetachedCriteria detachedCriteria){ zif()i
return(List) getHibernateTemplate QE-t v00
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().execute(new HibernateCallback(){ 8kO|t!?:U
publicObject doInHibernate 5/neV&VcB
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(Session session)throws HibernateException { -FE5sW
Criteria criteria = EeL~`$f
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detachedCriteria.getExecutableCriteria(session); EY> %#0
return criteria.list(); c3K(mM:
} E%/E%9-7\
}, true); sowkxw.^Q
} 3MkF
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public int getCountByCriteria(final @GjWeOj]
) VJ|
DetachedCriteria detachedCriteria){ aD%")eP%&
Integer count = (Integer) p?6w/ n
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getHibernateTemplate().execute(new HibernateCallback(){ Lo9+#ITyx
publicObject doInHibernate W;Fcp
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(Session session)throws HibernateException { R},mq&f5
Criteria criteria = ~e'FPVDn
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detachedCriteria.getExecutableCriteria(session); 0 ,Bd,<3
return TLO-$>h
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criteria.setProjection(Projections.rowCount KA%tVBl
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()).uniqueResult(); >&BgF*mm
} Sh{odrMj*
}, true); 1.jW^sM
return count.intValue(); ?XW+&!ar
} !K6: W1
} ioh_5
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用户在web层构造查询条件detachedCriteria,和可选的 Nb(se*Y#
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 C^l)n!fq
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PaginationSupport的实例ps。 +h*&r~T
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ps.getItems()得到已分页好的结果集 A5
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ps.getIndexes()得到分页索引的数组 $"x(:
ps.getTotalCount()得到总结果数 Y5Ey%Mm6
ps.getStartIndex()当前分页索引 /WMG)#kw'
ps.getNextIndex()下一页索引 @{XN}tWDOp
ps.getPreviousIndex()上一页索引 e`8z1r
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 zB 7wGl9
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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 >-+MWu=
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一下代码重构了。 r_
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我把原本我的做法也提供出来供大家讨论吧: 0#<_:E
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首先,为了实现分页查询,我封装了一个Page类: f~W.i]
java代码: :GGsQ
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/*Created on 2005-4-14*/ -YSn 3=
package org.flyware.util.page; w&C SE
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/** w_A-:S
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* @author Joa @RT yCr
* bFJmXx&
*/ FKL}6W:
publicclass Page { o&I0*~sN
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/** imply if the page has previous page */ zIRa%%.i<
privateboolean hasPrePage; MY1
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/** imply if the page has next page */ AS4m227
privateboolean hasNextPage; NP%ll e,l
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/** the number of every page */ \gIdg:"02
privateint everyPage; S2j7(T;~YB
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/** the total page number */ jY ^ndr0;
privateint totalPage; Q Z9)uI
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/** the number of current page */ UP, 0`fh(y
privateint currentPage; zU1rjhv+
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/** the begin index of the records by the current 5z El`h
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query */ G-,PsXSwe
privateint beginIndex; e(!a~{(kq%
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/** The default constructor */ ,QG,tf?
public Page(){ 4b7}Sr=`
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} EHo"y.ODg
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/** construct the page by everyPage G_dia6
* @param everyPage UDp"+nS
* */ _L# Tp
public Page(int everyPage){ /a9+R)Al
this.everyPage = everyPage; M~
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} 5HOhk"
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/** The whole constructor */ G. <9K9K
public Page(boolean hasPrePage, boolean hasNextPage, *sL'6"#Cre
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int everyPage, int totalPage, '| Ag,x[
int currentPage, int beginIndex){ hi.{
this.hasPrePage = hasPrePage; q8[Nr3.
this.hasNextPage = hasNextPage; 1b_->_9
this.everyPage = everyPage; " I _T
this.totalPage = totalPage; gvsS:4N"Nq
this.currentPage = currentPage; fnB-?8K<
this.beginIndex = beginIndex; pCpj#+|_)
} 4H\O&pSS
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/** ^P{'l^CVX
* @return jp[QA\
* Returns the beginIndex. +S3'ms
*/ 4&`66\p;
publicint getBeginIndex(){ qTffh{q V
return beginIndex; Tri.>@-u
} /Ee0S8!Z!1
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/** e3(0L I
* @param beginIndex UejG$JyHP
* The beginIndex to set. u2Rmp4]
*/ MJ92S(
publicvoid setBeginIndex(int beginIndex){ *>\RGL;]8
this.beginIndex = beginIndex; -3w? y
} ~t#'X8.)
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/** yn%w'
* @return 7:1Hgj(
* Returns the currentPage. Nwu#,f=X
*/ SM^6+L"BE
publicint getCurrentPage(){ HP?e?3.T
return currentPage; 5[Q44$a{
} FPcgQ
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/** wvUph[j}J
* @param currentPage Qh{=Z^r
* The currentPage to set. pwu5Fxn)
*/ %!eK"DKG^
publicvoid setCurrentPage(int currentPage){ 5Impv3qaZ
this.currentPage = currentPage; { !FrI@
} 8fDnDA.e
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/** G1P m!CM=
* @return }. ,xhF[
* Returns the everyPage. q=R=z$yr
*/ 0~FX!1;
publicint getEveryPage(){ _$, .NK,6
return everyPage; "ENgu/A!
} hl# 9a?
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/** pf2$%lE
* @param everyPage @<w$QD
* The everyPage to set. ^Yn6kF
*/ ,q:6[~n
publicvoid setEveryPage(int everyPage){ Q)Ppx 7)
this.everyPage = everyPage; =e ;\I/
} <89js87
}K&K{ 9}
/** )W c#?K
* @return "E'OPR
* Returns the hasNextPage. ]" )i~-|R
*/ YjsaTdZ!&
publicboolean getHasNextPage(){ i5)trSM|
return hasNextPage; 55yP.@i9J
} Bp4QHv9xqL
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/** n#x{~oQc
* @param hasNextPage ,ciNoP*-~%
* The hasNextPage to set. 38 B\ \
*/ Nzr zLK
publicvoid setHasNextPage(boolean hasNextPage){ #xts*{u-#
this.hasNextPage = hasNextPage; r]8B6iV
} Omh(UHZBB
l
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/** ;((gmg7,
* @return ;jnnCXp>
* Returns the hasPrePage. snN1
*/ }TYCF@
publicboolean getHasPrePage(){ Gz6FwU8L
return hasPrePage; i:W
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} 4; j#7
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/** +z9;BPw%
* @param hasPrePage aY"qEH7]
* The hasPrePage to set. JfC.U,7Nc
*/ (:@qn+
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publicvoid setHasPrePage(boolean hasPrePage){ iRPd=)
this.hasPrePage = hasPrePage; ayC*n'
} _ sM$O>
na/t=<{
/** i(Y P(8
* @return Returns the totalPage. PJb_QL!9
* _|~2i1Ms,
*/ 5"@<7/2qI
publicint getTotalPage(){ }3N8EmS
return totalPage; NO6. qWl
} g,Q!F
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/** 'jmcS0f
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* @param totalPage v<;,x
* The totalPage to set. @ZT25CD
*/ m*["
publicvoid setTotalPage(int totalPage){ jixU9]
this.totalPage = totalPage; '!En,*'IS
} {V:?r
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} @tp/0E?
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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 s-k-|4
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个PageUtil,负责对Page对象进行构造: ~\XB'
java代码: c*6o{x}K
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/*Created on 2005-4-14*/ VX;u54hS
package org.flyware.util.page; +n)(\k{
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import org.apache.commons.logging.Log; 8l)l9;4 6
import org.apache.commons.logging.LogFactory; d8Upr1_
+Cau/sPXL
/** {)F-US
* @author Joa {4:En;
* HqN|CwGgJ:
*/ F3 wRHq
publicclass PageUtil { BRH:5h
{\0 R[+d
privatestaticfinal Log logger = LogFactory.getLog sW=@G'}3
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(PageUtil.class); h8S%Q|-
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/** P,wFib^1
* Use the origin page to create a new page xD_jfAH'
* @param page 0A}'.LI
* @param totalRecords flb3Iih
* @return s
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*/ |y=CmNG,
publicstatic Page createPage(Page page, int Vy(lyD<6
{5_*f)$[H
totalRecords){ EBebyQcon
return createPage(page.getEveryPage(), e HOm^.gd
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page.getCurrentPage(), totalRecords); 4+ 4?0R
} XK&#K? M
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/** BkO"{
* the basic page utils not including exception ^?juY}rZ=|
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handler 2y<d@z:K
* @param everyPage R6M@pO
* @param currentPage !`aodz*PO
* @param totalRecords [s7I.rdGzz
* @return page Rl S=^}>
*/ IA+>dr
publicstatic Page createPage(int everyPage, int ? th+~dE
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currentPage, int totalRecords){ ob*2V!"
everyPage = getEveryPage(everyPage); -(1e!5_-@
currentPage = getCurrentPage(currentPage); b<[eBXe
int beginIndex = getBeginIndex(everyPage, esLY1c%"/
ow`\7qr
currentPage); h@Hmo^!9J
int totalPage = getTotalPage(everyPage, ZW\h,8%
50'6l
X(v,
totalRecords); Riw>cVi~
boolean hasNextPage = hasNextPage(currentPage, B1p9pr
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totalPage); Sa<R8X'J
boolean hasPrePage = hasPrePage(currentPage); dm.3. xXq
s%/0WW0y^
returnnew Page(hasPrePage, hasNextPage, 8 zY)0
everyPage, totalPage, k} <mmKB
currentPage, RP(FV<ot
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beginIndex); X0C\87xfG
} wicg8[T=B
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privatestaticint getEveryPage(int everyPage){ ](0A/,#q6
return everyPage == 0 ? 10 : everyPage; Nd6N:1-
} VLOyUt~O#
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privatestaticint getCurrentPage(int currentPage){ o@>5[2b4
return currentPage == 0 ? 1 : currentPage; _e-a>y
} .}0Cg2W
Dljq
privatestaticint getBeginIndex(int everyPage, int ZERd#7@m+
f{b"=hQ
currentPage){ |X_yL3`Zb
return(currentPage - 1) * everyPage; R.RCa$
} ,Wdyg8&.
}wUF#
privatestaticint getTotalPage(int everyPage, int b>waxQxjS
WFh!re%Z
totalRecords){ 9wAP%xh
int totalPage = 0; :`uo]B"
h.8J6;36
if(totalRecords % everyPage == 0) W*_ifZ0s.
totalPage = totalRecords / everyPage; 2h/`RefHJ
else _x>u"w
totalPage = totalRecords / everyPage + 1 ; 7aU*7!U
[`
i;gx[^
return totalPage; u4Xrvfb,
} wv*r}{%7g[
M2m@N-+R
privatestaticboolean hasPrePage(int currentPage){ T[7-3[w<)
return currentPage == 1 ? false : true; w.V8-9{
} g;*~xo
4f/8APA
privatestaticboolean hasNextPage(int currentPage, 7zNyH(.
}2{%V^D)r
int totalPage){ 5&VLq
return currentPage == totalPage || totalPage == iKdC2m
gFW1Nm_DJ
0 ? false : true; {j(,Q qB;f
} 9x:c"S*
,iHl;3bu
b _6j77
} S3n$
{0[qERj"z
0{jRXa-(
#kxg|G[Ol
iveWau292
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。 \75%[;.
++FMkeHZ
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 xvW+;3;
dvUJk<;w
做法如下: ty"k
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 F02NnF
PDtaL
的信息,和一个结果集List: qf'uXH
java代码: >
^D10Nf*
:vm*miOF
;Cv x48
/*Created on 2005-6-13*/ _I75[W!
package com.adt.bo; rH & ^SNc
*P9)M%
import java.util.List; j'v2m 6/
0OlB;
import org.flyware.util.page.Page; ?-Oy/Y K
<b{ApsRJf
/** ,%D \
* @author Joa (?$}Vp
*/ MQLa+I,S4
publicclass Result { <@JK;qm>S
o-49o5:1
private Page page; qd(`~a
k;q|pQ[
private List content; 0f1*#8-6
,7<5dIdZ
/** f%d7?<rw
* The default constructor wzF/`z&0?6
*/ ]iYjS
public Result(){ >u~
l_?
super(); U^:+J-z{
} W}XDzR'<
1VH7z
/** /tDwgxJ
* The constructor using fields epR7p^`7
* F0])g
* @param page #jbo!
wdg
* @param content Y!"LrkC
*/ [|E
93g
public Result(Page page, List content){ |3QKxS0
this.page = page; SfEgmp-m
this.content = content; gT?:zd=;
} M qFuZg
~*ST fyFw
/** [,yoFm%"
* @return Returns the content. :$L^l{gT
*/ +VCG/J
publicList getContent(){ ^yyL4{/
return content; Hj2E -RwG
} 2mRm.e9?
{ZrIA+eH
/** M4~^tML>Ey
* @return Returns the page. )E;B'^RVR
*/ ER;?[!
public Page getPage(){ N7=lSBm
return page; GHaD32
} WzDL(~m+Z
At3>
/** S ( e]@
* @param content PFq1Zai}n|
* The content to set. IT!u4iH[
*/ @Fvp~]jCb
public void setContent(List content){ 'I^3r~_
this.content = content; FN0)DN2d}
} +-"uJIwMD
' d' Dlg
/** "MM)AY*b
* @param page v P;
* The page to set. (JenTL`%u
*/ (
y0
publicvoid setPage(Page page){ %k3A`ClW
this.page = page; }w&W\g+E$
} C%&A9(jG
} ?VnA
\USl9*E
B6UTooj
?gYQE&M !
`
ES-LLhVf
2. 编写业务逻辑接口,并实现它(UserManager, `O,^oD4
c`,'[Q5(O
UserManagerImpl) _"l2UDx
java代码: AcHr X=O
$Iz *W]B!
-<0xS.^
/*Created on 2005-7-15*/ h8XoF1wuw
package com.adt.service; Dm{9;Abs%
8f`r!/j
import net.sf.hibernate.HibernateException; Nhf@Y}Cu
E5iNuJj=f
import org.flyware.util.page.Page; 6K7DZ96L
2^w8J w9
import com.adt.bo.Result; 5FMe &
{q!GTO
/** zQ~N(Jj?h
* @author Joa ~v>3lEGn*
*/ L$t.$[~L
publicinterface UserManager { 0?,<7}"<X
vC^Ul
public Result listUser(Page page)throws awB+B8^s
u~8=ikn+T
HibernateException; YQ|o0>
w!_6*
} */'j[uj
9;Qgby
2`^M OGYk
kxCN0e#_
`T,^os#6
java代码: ~F"w
#;0F-pt
Ua.%?V
/*Created on 2005-7-15*/ * ,Le--t
package com.adt.service.impl; |mQC-=6t;Y
ntxaFVD
import java.util.List; XUVBD;"f!
K%.t%)A_3
import net.sf.hibernate.HibernateException; 9
lXnNK
|]
;$vVYC
import org.flyware.util.page.Page; f"-3'kqo
import org.flyware.util.page.PageUtil; G){A&F
h$]nfHi_Q
import com.adt.bo.Result; Nd
He::
import com.adt.dao.UserDAO; /H*[~b
import com.adt.exception.ObjectNotFoundException; (qw;-A
W8
import com.adt.service.UserManager; .npD<*
SaOOD-u
/** KK?R|1VK9
* @author Joa BsR3$
*/ 0DaKd<Scv
publicclass UserManagerImpl implements UserManager { XMF#l]P
NC3XJ
4
private UserDAO userDAO; Ip0`R+8
m 0]1(\%
/** 06 an(&a9
* @param userDAO The userDAO to set. +^q-v-
*/ 7O~hA*Z
publicvoid setUserDAO(UserDAO userDAO){ S;SI#Vg@
this.userDAO = userDAO; [U,hb1Wi3
} :j[=
-n:;/ere7-
/* (non-Javadoc) xUPg~c0
* @see com.adt.service.UserManager#listUser je74As[
bSW~hyI w
(org.flyware.util.page.Page) b?-KC\}v
*/ |ADg#oX
public Result listUser(Page page)throws xf;Tk
CN6b982&
HibernateException, ObjectNotFoundException { :n OCs
int totalRecords = userDAO.getUserCount(); ybcCq]cgt
if(totalRecords == 0) M1eM^m8U
throw new ObjectNotFoundException
8#|PJc
g6H` uO
("userNotExist"); ~PX#' Jr
page = PageUtil.createPage(page, totalRecords); 7Q|v5@;pU
List users = userDAO.getUserByPage(page); /BrbP7
returnnew Result(page, users); |H%,>r`9S
} p[%B#(]9,
loD:4e1
} q+)s
xgIb4Y%
-e.ygiK.`S
W"g@*B'|
-l<[CI
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 Sr-!-eC
r#c+{yY
询,接下来编写UserDAO的代码: X1="1{8H
3. UserDAO 和 UserDAOImpl: H6Kt^s<6xu
java代码: `<?((l%;R
(X|lK.W y
lmx'w
/*Created on 2005-7-15*/ Px`z$~*B:
package com.adt.dao; ?e hUGvV2
@}tk/7-E
import java.util.List; )C>M74Bt
G}`Hu_ [\)
import org.flyware.util.page.Page; KRh?{
*%QTv3{
import net.sf.hibernate.HibernateException; \)BDl
88+J(^y>
/** +w+qTZyky
* @author Joa UzUt=s!^H
*/ )%9P ;/
publicinterface UserDAO extends BaseDAO { ETq~,g'
"3VMjF\
publicList getUserByName(String name)throws nNcmL/(
B1 [O9 U:
HibernateException;
!\_li+
g/ x\#W
publicint getUserCount()throws HibernateException; }'Yk#Q
)-d&XN7
publicList getUserByPage(Page page)throws 0V?:5r<
q/t~`pH3
HibernateException; 2bt2h.a
YGr^uTQb
} O$ ;:5zT
m_r_4BP
j?P8&Fm<
0x8aKq\'
3}X; WE `
java代码: dtUt2r)6L;
OcGHMGdn
|DMa2}%
/*Created on 2005-7-15*/ X8=sk
package com.adt.dao.impl; `)s>},8W!
6GtXM3qtS
import java.util.List; qddP -uN
[vY? !
import org.flyware.util.page.Page; rWMG_eP:
J2adA9R/,
import net.sf.hibernate.HibernateException; C/x<_VJzN/
import net.sf.hibernate.Query; l/w<R
e6WKZ~
vo
import com.adt.dao.UserDAO; o]|a5.O
:]oR x
/** =e$6o 2!'}
* @author Joa naoH685R4
*/ |,Xrt8O/[
public class UserDAOImpl extends BaseDAOHibernateImpl f*^)0Po
L(i*v5?
implements UserDAO { wIT}>8o
-w:F8k ~
/* (non-Javadoc) =D2x@ank[
* @see com.adt.dao.UserDAO#getUserByName )pAN_e"
;Y>cegG\
(java.lang.String) `+/xA\X]
*/ ^N5BJ'[F:
publicList getUserByName(String name)throws XABI2Ex
9(( QSX
HibernateException { 9V=bV=4:
String querySentence = "FROM user in class F!;0eS"xp
U ExK|t
com.adt.po.User WHERE user.name=:name"; 6T5nr
Query query = getSession().createQuery U{2UKD@PM
PDnwaK
(querySentence); 9\]%N;;Lo
query.setParameter("name", name); <([1(SY2e
return query.list(); |NcfR"[c
} RqIic\aD
IP` ;hC
/* (non-Javadoc) pGy(JvMw"
* @see com.adt.dao.UserDAO#getUserCount() |?!Ew# w
*/ #Pz},!7
publicint getUserCount()throws HibernateException { :>.~"uWo{
int count = 0; Dm1;mR S+
String querySentence = "SELECT count(*) FROM \Om<
FH}
qd B@P
user in class com.adt.po.User"; 8S>T1st
Query query = getSession().createQuery f-?00*T
>y&4gm
(querySentence); zhDmZ
count = ((Integer)query.iterate().next )hHkaI>eYv
aD~3C/?aW
()).intValue(); .ya^8gM
return count; :o}Ju}t
} N.|Zh+!
$e; _N4d^
/* (non-Javadoc) ;K:)R_H
* @see com.adt.dao.UserDAO#getUserByPage @'DfNka
;wfzlUBC
(org.flyware.util.page.Page) Nkt(1?:-'
*/ P+sxlf:0
publicList getUserByPage(Page page)throws $up.<qzj
xS` %3+|
HibernateException { dlC)&Ai
String querySentence = "FROM user in class %v\0Dm+A
9}FWO&LiB
com.adt.po.User"; j(!M
Query query = getSession().createQuery ? Ovl(4VG
<@}~Fp@
(querySentence); 8YAUy\
query.setFirstResult(page.getBeginIndex()) /lSz8h2
.setMaxResults(page.getEveryPage()); /a\6&Eb
return query.list(); /a%5!)NE%
} h5&l#>8&
Us'm9 J
} 8H3|i7.1h
=N`"%T@=
maLKUSgo
^o]ZDc
mvI[=e*
至此,一个完整的分页程序完成。前台的只需要调用 TdI5{?sW
R74kt36M
userManager.listUser(page)即可得到一个Page对象和结果集对象 `'[u%U E
zg&<HJO
的综合体,而传入的参数page对象则可以由前台传入,如果用 ,V!s w5_5m
+?n81|7`
webwork,甚至可以直接在配置文件中指定。 4;_{* U-
R:98'`X=
下面给出一个webwork调用示例: Z VuHO7'
java代码: $
+;`[b
l [?o du4
-:`$8/A|
/*Created on 2005-6-17*/ a|`Pg1j#
package com.adt.action.user; n'{cU(
0b9K/a%sQv
import java.util.List; bE.,)GY
u~\u8X3
import org.apache.commons.logging.Log; s<[%76Y!
import org.apache.commons.logging.LogFactory; [k.|iCD
import org.flyware.util.page.Page; ~`c?&YixU
1HG~}E
import com.adt.bo.Result; Y~vI@$<~(
import com.adt.service.UserService; Rz1&(_Ps
import com.opensymphony.xwork.Action; V} Y %9V
Od70w*,
/** ~h6aw
* @author Joa "qUUH4mR`
*/ `:!mPNW#
publicclass ListUser implementsAction{ eKNZ?!c=
q?g4**C
privatestaticfinal Log logger = LogFactory.getLog "tB"C6b
r7/y'Y]O
(ListUser.class); Vu0jNKUV
Y;d$x}dh
private UserService userService; $Zp\^cIE+
.w\AyXp
private Page page; u
HqP b8
2`I"
QU
privateList users; a}ogNx
eWSA
/* fEE[huG
* (non-Javadoc) m8;;
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* hIu;\dfwk
* @see com.opensymphony.xwork.Action#execute() !`L%wS
*/ #z_lBg. K
publicString execute()throwsException{ T;qP"KWZ
Result result = userService.listUser(page); #L5H-6nz
page = result.getPage(); HtB>#`'
users = result.getContent(); 2apR7
return SUCCESS; z^+f3-Z
} oBiJiPE=`
Nw[TP
G5
/** iTF`sjL
* @return Returns the page. u8L%R[#o
*/ m`gH5vQa
public Page getPage(){ G=Hvh=K(
return page; &?flH;
} t?f2*N:
S[(Tpk2_
/** fTd=}zY
* @return Returns the users. *Z\B9mx
*/ IHHL. gT
publicList getUsers(){ P}hHx<L
return users; AL@8v=
} I WKq_Zjkz
dPZrX{ c
/** yXP+$oox9
* @param page Hc^q_{}"
* The page to set. nR'!Ui
*/ &{E1w<uv
publicvoid setPage(Page page){ ;:2]++G
this.page = page; 0'q&7
MV
} KSkT6_<
D*.U?
/** Em8q1P$tm>
* @param users 6Hoc F/Ye
* The users to set. >tc#Ofgzd
*/ Ug(;\*yg
publicvoid setUsers(List users){ EQ< qN<uW
this.users = users; nk=+6r6
} FyleK+D?
]e`&py E
/** 8Ld{Xg
* @param userService @p`*MWU
* The userService to set. ;;>hWAS
*/ -u+@5K;^Y
publicvoid setUserService(UserService userService){ ws}cMX]*
this.userService = userService; n!Hj4~T0
} )B"k;dLm
} y,&'nk}
T($d3Nn1
3s%Kw,z
Vx'82CIC
1M@OBfB8
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, ]k+XL*]' A
%vF,wQC
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 arVu`pD*n
9mA6nmp
么只需要: @6["A'h
java代码: `G/%U~
j8P qc]
Ygeg[S!7
<?xml version="1.0"?> rF@njw@
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork b"4'*<=au
ws/e~ T<c
1.0//EN" "http://www.opensymphony.com/xwork/xwork- -d-vzri
+"mS<
1.0.dtd"> ,gO}H)v]t
b@v_db]|t.
<xwork> zv%]j0 ?
"aL.`^.
<package name="user" extends="webwork- 6DkFI kS
D;1?IeS
interceptors"> 0Y>5&
d9=i{i3
<!-- The default interceptor stack name ,r5'nDV=d
^Uq%-a
--> +DsdzR`Gx,
<default-interceptor-ref H|\@[:A+
1j_gQ,'20
name="myDefaultWebStack"/> yf4I<v$y
\=1$$EDS9
<action name="listUser" 6y+_ x'
NZb}n`:
class="com.adt.action.user.ListUser"> #zf,%IYF
<param Tv[|^G9x
?td`*n~,
name="page.everyPage">10</param> y:HH@aa)
<result 1G'D'
2RbK##`vC
name="success">/user/user_list.jsp</result> PtTL
tiE~
</action> "M;aNi^B
)5[OG7/g
</package> 8P?p
ROhhd.
</xwork> u<['9U
,*kh{lJ
`VrQ?s
^?V9
wi/qI(O!
$5wf{iZY.Q
这样就可以通过配置文件和OGNL的共同作用来对page对象设置初值 j.ZXLe~
m9=93W?
了。并可以通过随意修改配置文件来修改每页需要显示的记录数。 ^)E#
c
)Drif\FF)
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 Bwc_N.w?3
|s'5~+
LO;?#e7
|jB/d@RE
g)1`A24
我写的一个用于分页的类,用了泛型了,hoho x~JOg57up
+-!2nk`"a
java代码: +QEP:#qZw
/o^/J~/3
FEO/RMh
package com.intokr.util; G3o `\4p
jdIAN
import java.util.List; FN/siw(?3
x
}@P
/** ZY|$[>X!
* 用于分页的类<br> F!<!)_8Q
* 可以用于传递查询的结果也可以用于传送查询的参数<br> feJl[3@tO
* VfFbZds8f
* @version 0.01 ||))gI`3a
* @author cheng &^7(?C'u
*/ z22:O"UHa
public class Paginator<E> { u`;P^t5
privateint count = 0; // 总记录数 ?IG[W+M8
privateint p = 1; // 页编号 YrsE
88QqI
privateint num = 20; // 每页的记录数 q+BG
privateList<E> results = null; // 结果 "vX\Q rL
je`Inn<
/** :Y|[?;
* 结果总数 ?=im~
*/ L_tjclk0J
publicint getCount(){ [V_+/[AA)
return count; p<<dj%
} NwVhJdo
'6cXCO-_P
publicvoid setCount(int count){ vY7@1_"
this.count = count; pL . 0_
} &smZ;yb|'h
uu.}<VM.1
/** ~9PZ/(
'
* 本结果所在的页码,从1开始 6OB3%R'p
* l.P;85/+
* @return Returns the pageNo. +sV~#%%
*/ !;4Hh)2
publicint getP(){ .%!^L#g
return p; G^';9 UK
} !L@<?0xLW
E3]
8(P%D-
/** I9dX\w}
* if(p<=0) p=1 U~d%5?q
* 5,4m_fBoW
* @param p sm;kg=
*/ Cg|\UKfy$
publicvoid setP(int p){ s7 sTY
if(p <= 0) {VXucGI|
p = 1; O~v~s
'c&
this.p = p; <k0/O
} tLxeq?Oo]
Uu52uR
/** 80`$F{xcX
* 每页记录数量 jSSEfy>^
*/ $ai;8)C6
publicint getNum(){ 9 r&JsCc
return num; $$uMu{?0i
} +,]VXH<y
CZ'm|^S
/** 0OQ*V~>f
* if(num<1) num=1 N:okt)q:%
*/ J .VZD
publicvoid setNum(int num){ $7ix(WL<%
if(num < 1) x7Gf):,LK
num = 1; L`e19I$
this.num = num; aj,o<J
} o(H.1ESk
Z zjCS2U
/** 0\vG
<
* 获得总页数 ~
rQ,%dH
*/ &r~s3S{pQ
publicint getPageNum(){ 'n
^,lXWB
return(count - 1) / num + 1; `uUzBV.FR
} KQvSeH>r
5&h">_j
/** %q~q,=H$]
* 获得本页的开始编号,为 (p-1)*num+1 b$%Kv(
*/ 01n132k
publicint getStart(){ 77y+ik
return(p - 1) * num + 1; <9piKtb|L
} .c~z^6x
h6OQeZ.
/** P tLWFO
* @return Returns the results. "M!m-]
*/ >Q!}tbg~9
publicList<E> getResults(){ \/?J)k3H.
return results; @4D{lb"{
} gBi3^GxjM?
lux
g1>
public void setResults(List<E> results){ N%xCyZ
this.results = results; zSQy
} \~z$'3H`
iB"ji4[z
public String toString(){ |bnYHP$!
StringBuilder buff = new StringBuilder }8#Ed;%K
FRZ]E)9Z]b
(); R:YVmqd
buff.append("{"); /\b*
oPWJ
buff.append("count:").append(count); Zfcf?&><
buff.append(",p:").append(p); 2dkWzx
buff.append(",nump:").append(num); t@9-LYbL
buff.append(",results:").append X,_K
)f
_1qR1<V
(results); }O
$]xB
buff.append("}"); #`
gu<xlW
return buff.toString(); 8K-P]]
} HXSryjF?
!ess.U&m'
} sdg2^] |
$zp|()_
05T?c{ ;