Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 H`P )
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 b7n~z1$
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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 Bw$-*FYE
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自于Quake Wang的javaeye-core包的相应类,然后又做了很多修改 oTL "]3`'
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分页支持类: ]:njP3r
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java代码: ; ^$RG
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package com.javaeye.common.util; yP-Dj
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import java.util.List; |LQmdgVr$
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publicclass PaginationSupport { g
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publicfinalstaticint PAGESIZE = 30; yF:fxdpw
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privateint pageSize = PAGESIZE; CR/LV]G
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privateList items; IJ0RHDod:
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privateint totalCount;
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privateint[] indexes = newint[0]; k91Y"_&
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privateint startIndex = 0; }"T:z{n
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public PaginationSupport(List items, int 2vwT8/
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totalCount){ ]
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setPageSize(PAGESIZE); ka5>9E
setTotalCount(totalCount); AkF1Hj
setItems(items); %8ul}}d9
setStartIndex(0); |`|b&Rhu
} 2@H~nw 0
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public PaginationSupport(List items, int =m40{
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totalCount, int startIndex){ q\~7z1
setPageSize(PAGESIZE); LP87X-qkjW
setTotalCount(totalCount); 9=/8d`r
setItems(items); WgIVhj
setStartIndex(startIndex); V=c&QPP
} f="}.
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public PaginationSupport(List items, int Y}Ov`ZM!r
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totalCount, int pageSize, int startIndex){ G0^PnE0-
setPageSize(pageSize); 464Z0C
setTotalCount(totalCount); n_!&Wr^CX
setItems(items); bi5'- .B
setStartIndex(startIndex); u&<LW4
} iZ58;`
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publicList getItems(){ oU2RxK->u
return items; C>;}CH|X
} l/`Z+];
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publicvoid setItems(List items){ B<oi,S
this.items = items; Ywni2-)<
} ]6nF>C-C
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publicint getPageSize(){ =?}'\
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return pageSize; _WkK%RYV
} 4Qw!YI#40$
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publicvoid setPageSize(int pageSize){ )&w\9}B:
this.pageSize = pageSize; H'Po
} c"|^Lo.
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publicint getTotalCount(){ mX#T<_=d
return totalCount; zR/ATm]9
} {c$W-t):U|
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publicvoid setTotalCount(int totalCount){ 9/'j<v6M
if(totalCount > 0){ d BJM?/
this.totalCount = totalCount; b w cPY
int count = totalCount / MXhS\vF#m
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pageSize; /E*P0y~KTW
if(totalCount % pageSize > 0) ]M2> %Dvw
count++; TKmC/c
indexes = newint[count]; gKPV*
for(int i = 0; i < count; i++){ xNx!2MrR;
indexes = pageSize * *BF1Sso
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i; 3U}z?gP[
} CfVz'
}else{ {d3r>Ub)7d
this.totalCount = 0; :gR`rc!
} <}e<Zf!
} 1mB6rp
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publicint[] getIndexes(){ uW[<?sFG
return indexes; m1frN#3
} .
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publicvoid setIndexes(int[] indexes){ 5$y<nMP
this.indexes = indexes; !|}>Y
} vzVl2
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publicint getStartIndex(){ YX~H!6l
return startIndex; *d%m.:)N
} a MzAA
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publicvoid setStartIndex(int startIndex){ \zKVgywR
if(totalCount <= 0) s*S@}l
this.startIndex = 0; t!PFosFp
elseif(startIndex >= totalCount) 1e&`m~5K+
this.startIndex = indexes h[ tOY
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[indexes.length - 1]; BtjsN22
elseif(startIndex < 0) pE=wP/#
this.startIndex = 0; 8*|@A6ig
else{ fc
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this.startIndex = indexes 3GaM>w}>W
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[startIndex / pageSize]; O/GD[9$i
} a
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} `]fY9ZDKs
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publicint getNextIndex(){ / ]I]
int nextIndex = getStartIndex() + Z'u`)jR
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pageSize; <yIJ$nBx
if(nextIndex >= totalCount) WJ
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return getStartIndex(); 643 O(0a
else Qz
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return nextIndex; QK;A>]
} Zaq:l[%
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publicint getPreviousIndex(){ V{(ve#y7`{
int previousIndex = getStartIndex() - &<L+;k~P%
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pageSize; u[cbRn,W
if(previousIndex < 0) 4u"O/rt
return0; YHE7`\l
else H1q>UU:
return previousIndex; AN^;~m ^
} K}Aaflq
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} 51L:%Af
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抽象业务类 mvYr"6f8
java代码: Iy"
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/** ;Ni+TS
* Created on 2005-7-12 Rh:\/31~
*/ 03#r F@e
package com.javaeye.common.business; '?q|7[SU
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import java.io.Serializable; cz.-cuD[iD
import java.util.List; Tl 9_Wi
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import org.hibernate.Criteria; _sw,Y!x%dF
import org.hibernate.HibernateException; \<V{6#Q=
import org.hibernate.Session; uTOL
import org.hibernate.criterion.DetachedCriteria; .\i9}ye
import org.hibernate.criterion.Projections; y|c]r!A
import _e/vw:
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org.springframework.orm.hibernate3.HibernateCallback; .(3B}}gB>
import I2D<~xP~2+
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org.springframework.orm.hibernate3.support.HibernateDaoS Rh~<#"G]
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upport; ZSHc@r*>
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import com.javaeye.common.util.PaginationSupport; Kh3*\x T
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public abstract class AbstractManager extends N!$y`nwiw'
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HibernateDaoSupport { *"4
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privateboolean cacheQueries = false; #j'OrD
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privateString queryCacheRegion; kE/>Ys@w
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publicvoid setCacheQueries(boolean wB"&K;t
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cacheQueries){ ~^:/t<N
this.cacheQueries = cacheQueries; F@&q4whaVD
} IL`5RZi1
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publicvoid setQueryCacheRegion(String = R; 0Ed&b
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queryCacheRegion){ X+Xjf(
this.queryCacheRegion = pX|\J>u)
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queryCacheRegion; 6Kg
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} N!aV~\E
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publicvoid save(finalObject entity){ &QLCij5:
getHibernateTemplate().save(entity); hG; NJx-=R
} F<
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publicvoid persist(finalObject entity){ wbVM'E/&
getHibernateTemplate().save(entity); 61b,+'-
} MiAXbo#\
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publicvoid update(finalObject entity){ |$^,e%bE
getHibernateTemplate().update(entity); X 1^f0\k
} l8n#sGA %
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publicvoid delete(finalObject entity){ $]!uX&
getHibernateTemplate().delete(entity); p%_r0
} -Z)$].~|t
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publicObject load(finalClass entity, T&6{|IfM_
{ SJ=|L6
finalSerializable id){ WSKG8JT^|
return getHibernateTemplate().load {PWz:\oaD
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(entity, id); !JJCG
} ey@y?X=
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publicObject get(finalClass entity, XLI'f$w&
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finalSerializable id){ a|
return getHibernateTemplate().get )
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(entity, id); iMYvC w/t6
} Ilsh
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publicList findAll(finalClass entity){ :$j!e#?=
return getHibernateTemplate().find("from ]Y}faW(&Y
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" + entity.getName()); k-Le)8+b
} ) yRC$7I
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publicList findByNamedQuery(finalString V
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namedQuery){ _T<ney}Y<
return getHibernateTemplate >5i1M^g(
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().findByNamedQuery(namedQuery); kT []^Jtc
} &7XB$
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publicList findByNamedQuery(finalString query, 0+m"eGwTm
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finalObject parameter){ l92#F*
return getHibernateTemplate 'w^1re=R
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().findByNamedQuery(query, parameter); !f V.#9AB#
} 8HxB\ !0F?
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publicList findByNamedQuery(finalString query, w(<;
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finalObject[] parameters){ rbqH9 S
return getHibernateTemplate VABrw t
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().findByNamedQuery(query, parameters);
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} *B#<5<T
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publicList find(finalString query){ [="moh2*f
return getHibernateTemplate().find )U`H7\*)
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(query); ^-f5;B`\i
} x\3tSP7Vp
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publicList find(finalString query, finalObject _|g(BK2}
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parameter){ H7H'0C
return getHibernateTemplate().find bv)E>%Yy
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(query, parameter); b^;19]/RW
} -!I.:97 N
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public PaginationSupport findPageByCriteria ,.x5
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(final DetachedCriteria detachedCriteria){ <YUc?NF
return findPageByCriteria Fx/9T2%=
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); {(7Dz*0
} 9c}LG5
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public PaginationSupport findPageByCriteria LyS139P$
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(final DetachedCriteria detachedCriteria, finalint J3}^\k=p"
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startIndex){ ;_F iiBk7(
return findPageByCriteria [64K?l0&
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(detachedCriteria, PaginationSupport.PAGESIZE, Go^W\y
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startIndex); d9R0P2
} yaa+j8s]
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public PaginationSupport findPageByCriteria w(k7nGU]
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(final DetachedCriteria detachedCriteria, finalint 4O[5,
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pageSize, FJ!N)`[
finalint startIndex){ &bRmr/D
return(PaginationSupport) ^8
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getHibernateTemplate().execute(new HibernateCallback(){ _g0
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publicObject doInHibernate M#=woj&[
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(Session session)throws HibernateException { ) Z0
Criteria criteria = VCX})sp
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detachedCriteria.getExecutableCriteria(session);
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int totalCount = YEXJh!X
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((Integer) criteria.setProjection(Projections.rowCount 6(ju!pE`
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()).uniqueResult()).intValue(); n'ZlIh
criteria.setProjection c5mv4 MC
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(null); >M[rOu
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List items = Oa$ew'
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criteria.setFirstResult(startIndex).setMaxResults <;Qle
n?YGXW/
(pageSize).list(); Ud*.[GRD~
PaginationSupport ps = c42p>}P[
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new PaginationSupport(items, totalCount, pageSize, 4Qz
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startIndex); R
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return ps; lh(A=hn"n
} 5u~Ik c~
}, true); 1&i!92:E
} P+%O]v1 Ob
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public List findAllByCriteria(final x1|5q/I
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DetachedCriteria detachedCriteria){ pn{.oXomf
return(List) getHibernateTemplate $qP9EZ]JC
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().execute(new HibernateCallback(){ Lyt6DvAp"
publicObject doInHibernate XFG]%y=/6
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(Session session)throws HibernateException { RgRyo
Criteria criteria = e@L+z
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detachedCriteria.getExecutableCriteria(session); P2 !~}{-
return criteria.list(); F2z^7n.S
} Mff_j0D
}, true); E@0wt^
} E{wVf_K
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public int getCountByCriteria(final U%t:]6d&}
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DetachedCriteria detachedCriteria){ `w[0q?}"`
Integer count = (Integer) FGy7KVR
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getHibernateTemplate().execute(new HibernateCallback(){ m&Ms[X
publicObject doInHibernate xZGR<+t
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(Session session)throws HibernateException { }{bO~L7
Criteria criteria = PcM:0(,G
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detachedCriteria.getExecutableCriteria(session); >| .jG_s
return u32wS$*8
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criteria.setProjection(Projections.rowCount feQ_dA q
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()).uniqueResult(); rYJt;/RtR}
} jcXb@FE6
}, true); O4]Ss}ol
return count.intValue(); &|n*&@fF
} Af5In9WB5
} A!Xn^U*p
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用户在web层构造查询条件detachedCriteria,和可选的 k8Qv>z
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 rouD"cy
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PaginationSupport的实例ps。 03$Ay_2
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ps.getItems()得到已分页好的结果集 3|P P+<o
ps.getIndexes()得到分页索引的数组 rH8?GR0<
ps.getTotalCount()得到总结果数 _q3SR[k+`
ps.getStartIndex()当前分页索引 )Qw|)='-
ps.getNextIndex()下一页索引 ln3x1^!
ps.getPreviousIndex()上一页索引 >Q[]i4*A
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 }gag?yQ.^
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,尤其是上面的示例代码,让我着实觉得该对我原来的分页查询做 /e4hB
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一下代码重构了。 !%T@DT=l&
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我把原本我的做法也提供出来供大家讨论吧: n)$ q*IN"
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首先,为了实现分页查询,我封装了一个Page类: :L*CL 8m
java代码: l]oGhM;
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/*Created on 2005-4-14*/ _ F@>?\B
package org.flyware.util.page; CDU^X$Q
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/** 2=["jP!B
* @author Joa KhXW5hS1
* X+P3a/T
*/ ;2#7"a^
publicclass Page { W5J"#^kdF8
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/** imply if the page has previous page */ *!C^L"i
privateboolean hasPrePage; Vi5RkUY]
vlEd=H,LT
/** imply if the page has next page */ Vu~mi%UH
privateboolean hasNextPage; AL
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/** the number of every page */ 4A|5eg9N
privateint everyPage; \-V
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/** the total page number */ `A&64D
privateint totalPage; XImb"7|
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/** the number of current page */ `4\ H'p
privateint currentPage; ]#3=GFs/
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/** the begin index of the records by the current -_b}b)2iYN
42Kzdo|}
query */ @105 @9F
privateint beginIndex; CIO&VK
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/** The default constructor */ K'1rS[^>R
public Page(){ }KS[(Q
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} D?X97jNm
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/** construct the page by everyPage =]Qu"nRB
* @param everyPage |JuXOcr4
* */ 2)4{
public Page(int everyPage){ q SCt=eQ
this.everyPage = everyPage; JK[7&C-O
} t?YGGu^
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/** The whole constructor */ .hETqE` E
public Page(boolean hasPrePage, boolean hasNextPage, 3<'SnP3mY
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int everyPage, int totalPage, $Iqt
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int currentPage, int beginIndex){ T][\wyLx1
this.hasPrePage = hasPrePage; Q\ro )r
this.hasNextPage = hasNextPage; 33"{"2==`
this.everyPage = everyPage; ;rd!kFd#bq
this.totalPage = totalPage; x<9|t(
this.currentPage = currentPage; )Cu"M#`
this.beginIndex = beginIndex; 0o`0Td
} TtkB
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/** Oyj!N`&z@
* @return 2\EMtR>.M'
* Returns the beginIndex. |iO2,99i
*/ 8M(N
publicint getBeginIndex(){ 0~an\4nh
return beginIndex; >MiA|N=
} *K-,<hJ#L
dIIsO{Zqv
/** "F)7!e
* @param beginIndex TxPP{6t
* The beginIndex to set. 4s0>QD$J
*/ ^t9"!K
publicvoid setBeginIndex(int beginIndex){ Ao?H.=#y
this.beginIndex = beginIndex; JGH9b!}-1
} X$PT-~!a
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/** <t]i'D(K
* @return 7&m*:
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* Returns the currentPage. >UR-37g{p
*/ "qQU ^FW
publicint getCurrentPage(){ -pa.-@
return currentPage; @36^4E>h
} '<4OA!,^)
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/** 1*;?uC\
* @param currentPage ^N0hc!$
* The currentPage to set. vEn12s(lj
*/ {l_R0
publicvoid setCurrentPage(int currentPage){ 4/Ok/I
this.currentPage = currentPage; ZNG.W0{p
} |Q.?<T:wt=
/$I&D}uR`
/** _%Mu{Ni&
* @return %)\Cwl
* Returns the everyPage. DRf~l9f
*/ B3XVhUP
publicint getEveryPage(){ %Ljc#AVg
return everyPage; fN8A'p[
} N#]f?6*R
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/** a]
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* @param everyPage /c__{?go
* The everyPage to set. 1cOp"!
*/ a,lH6lDk
publicvoid setEveryPage(int everyPage){ L-G186B$r
this.everyPage = everyPage; P{rJG
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} * Oyic3F
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/** EUUj-.dEN
* @return kc/h]B
* Returns the hasNextPage. .R biF
*/ &<.Z4GxS
publicboolean getHasNextPage(){ mxGvhkj
return hasNextPage; o.}^6.h"
} &&JI$x0;
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/** j!:U*}f
* @param hasNextPage #@lr$^M
* The hasNextPage to set. -v >BeVF
*/ E62VuX
publicvoid setHasNextPage(boolean hasNextPage){ <Hm:#<\
this.hasNextPage = hasNextPage; jwAO{.}T1r
} gh i!4
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/** }u:^ Mz
* @return dpE\eXoa,
* Returns the hasPrePage. {&w%3
*/ }wj*^>*
publicboolean getHasPrePage(){ )k29mqa`
return hasPrePage; #; }IHAR
} V/>SjUNq
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/** ^/Gjk
* @param hasPrePage Mk,8v],-Tj
* The hasPrePage to set. kDO6:sjR7
*/ fbo64$!hZ
publicvoid setHasPrePage(boolean hasPrePage){ `acorfpi
this.hasPrePage = hasPrePage; :M|bw{P*
} ^b>E_u
pPG!{:YT
/** fBw+Y4nCO7
* @return Returns the totalPage. _[XEL+.
* YVu8/D@ o
*/ y%ER51+
publicint getTotalPage(){ (IJf2
return totalPage; f&^Ea-c
} Y k~ i.p
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/** 8a.
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* @param totalPage T7cT4PAW
* The totalPage to set. \mWXr*;
*/ S)JZb_
publicvoid setTotalPage(int totalPage){ jcx/ZR
this.totalPage = totalPage; >`,v?<>+
} t#Yyo$9
iVXR=A\er
} WMh'<'wN_
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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 <| Z0|sel
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个PageUtil,负责对Page对象进行构造: -cq ~\m^6
java代码: Of([z!'Gc
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/*Created on 2005-4-14*/ |W:kzTT-T
package org.flyware.util.page; ua7I K~8l
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import org.apache.commons.logging.Log; s8eiq`6\H}
import org.apache.commons.logging.LogFactory; )2rI/=R
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/** R+!2 j
* @author Joa fjp>FVv3
* {"{J*QH
*/ )#*c|.
publicclass PageUtil { .=^h@C*
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privatestaticfinal Log logger = LogFactory.getLog :VLuI
rD$7;
(PageUtil.class); ^D vaT9s
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/** ^T^U:Zdq
* Use the origin page to create a new page {p6",d."N&
* @param page |S>nfL{TQe
* @param totalRecords 3t%uUkXl
* @return o2Pj|u*X
*/ *jA%.F
publicstatic Page createPage(Page page, int }$AC0
@ Cqg2
totalRecords){ ZTt%7K"L
return createPage(page.getEveryPage(), $RA"NIZ:!
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page.getCurrentPage(), totalRecords); 8|7Tk[X1j
} 6{+~B2Ef
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/** ;?n*w+6<
* the basic page utils not including exception $T3/*xN
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handler {MYlW0)~
* @param everyPage 4eIu@
";!
* @param currentPage 6e~+@S
* @param totalRecords j&8 ~X2?*
* @return page Oa@X! \
*/ dWm[#,Q?
publicstatic Page createPage(int everyPage, int !4oYQB
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currentPage, int totalRecords){ T<! `~#kM
everyPage = getEveryPage(everyPage); )(DV~1r=
currentPage = getCurrentPage(currentPage); p}(w"?2
int beginIndex = getBeginIndex(everyPage, vBM\W%T|d
&V$'{
currentPage); R9=,T0Y
p
int totalPage = getTotalPage(everyPage, jl:O~UL6i
/9GqEQsfM
totalRecords); c+4SGWmO
boolean hasNextPage = hasNextPage(currentPage, +m>Kb edl
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totalPage); $L`7(0U-
boolean hasPrePage = hasPrePage(currentPage); bWMM[pnL
<T0-m?D_$
returnnew Page(hasPrePage, hasNextPage, R^8Opf_UN
everyPage, totalPage, < W&~tVv
currentPage, 2]4R`[#
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beginIndex); n\cP17dr
} Bq:@ [pCQ
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privatestaticint getEveryPage(int everyPage){ `yC
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return everyPage == 0 ? 10 : everyPage; eJy@N
} \LM'KD pP_
4>5%SzZT\3
privatestaticint getCurrentPage(int currentPage){ -,5g cD
return currentPage == 0 ? 1 : currentPage; K5w22L^=+
} _=}Y
lR
H56e#:[$
privatestaticint getBeginIndex(int everyPage, int Ir}&|"~H
_n{N3da
currentPage){ j83p[qR7o
return(currentPage - 1) * everyPage; G_AAE#r`
} possM'vC
&"^A
privatestaticint getTotalPage(int everyPage, int t-E'foYfr`
gXH89n
totalRecords){ DI$zyj~3
int totalPage = 0; EkTen:{G
P, S9gG9
if(totalRecords % everyPage == 0) 4AF"+L
totalPage = totalRecords / everyPage; f-{[ushj
else IndNR:"g
totalPage = totalRecords / everyPage + 1 ; Rj E,Wn
=#+Z KD
return totalPage; 9Pem~<
} =,0E3:X^
?W(wtp,o
privatestaticboolean hasPrePage(int currentPage){ FAQ:0L$G
return currentPage == 1 ? false : true;
?T4%"0
} I1}{7-_t
\XB71DUF
privatestaticboolean hasNextPage(int currentPage, FG8bP
Bj]0Cz
int totalPage){ ~Q]B}qdm
return currentPage == totalPage || totalPage == -rH3rKtf~
p>!r[v'
0 ? false : true; a.]
!
} Z;n}*^U
U7ajDw
B8TI 5mZ4
} iK.MC%8?
Dt+"E
kYR&t}jlCg
j+c)%
[C d2L&9
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。 U9N}6a=
%NAz(B
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 @Sv
?Ar
;^
/9sLW?#
做法如下: x]{h$yI
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 ]gmf%g'C
!'[sV^ds
的信息,和一个结果集List: wCI.jGSBW
java代码: i_=P!%,
FS@SC`~(
8KAyif@1::
/*Created on 2005-6-13*/ gK%&VzG4
package com.adt.bo; S$$:G$j
Cu|n?Uk
import java.util.List; -}N{'S,Bp
HV?awc
import org.flyware.util.page.Page; 1DLQZq
".@SQgyb0
/** g`&pQ%|=
* @author Joa &Owt:R)9~
*/ 5T;_k'qe
publicclass Result { T+~~w'v0
tSOF7N/<
private Page page; uZQ)A,#n;
1-qQp.Wj
private List content; n"MFC
}'Z(J)Bg
/** z_Qw's
* The default constructor |H@M-
*/ ~XZ1,2jA/
public Result(){ B\("08x
super(); +HfjnEbtBs
} aG"UV\
m|-O/6~
/** (JM4W
"7'
* The constructor using fields 6dinC <[}
* E? FPxs
* @param page @*c+`5)_
* @param content x[>A'.m@)
*/ eEU:
public Result(Page page, List content){ Q%
dpGI
this.page = page; RL&*.r&
this.content = content; KlrKGmy,)
} N.&K"J
S>*T&K
/** iYnw?4Y
* @return Returns the content. Y&&Y:+
V
*/ !
4s$93
publicList getContent(){ V*)6!N[5
return content; {$s:N&5
} r]]Ke_s!
~q1s4^J
/** @L~y%#
* @return Returns the page. '17=1\Ss6;
*/ ~pF'Qw"z|
public Page getPage(){ o+ tY[UX
return page; [@\f 0R
} OsK=% aDpj
h`vM+,I
/** NuP@eeF>,
* @param content y'+^
ME$H
* The content to set. jf%Ydr}`
*/ k5ZwGJ#r
public void setContent(List content){ l'o}4am
this.content = content; P/y-K0u
} ^X_%e |
f9&D1Gh+w
/** ^Krkf4fO
* @param page pa\]@;P1
* The page to set. D{8V^%{
*/ '@:;oe@]
publicvoid setPage(Page page){ 9YvMJ
this.page = page; leD?yyjw7
} r@!~l1$s`
} a
v`eA`)S
*3k~%RM%?
@TH \hr]
M)LdGN?$
MDB}G
'
2. 编写业务逻辑接口,并实现它(UserManager, W5x]bl#
UGN. ]#"#
UserManagerImpl) &R8zuD`#
java代码: OE[/sv
zO+nEsf^O
m83i6"!H
/*Created on 2005-7-15*/ =_UPZ]
package com.adt.service; )0%<ZVB
V3m!dp]
import net.sf.hibernate.HibernateException; <e=0J8V8,i
wWm#[f],?
import org.flyware.util.page.Page; vx
,yz+yP
|_ @iaLE
import com.adt.bo.Result; gVD!.
$Z(zO;k.
/** fDRQ(}
* @author Joa bk7miRIB
*/ 2?"9NQvz
publicinterface UserManager { G?"1
z;
h?R-t*G?
public Result listUser(Page page)throws 6iTDk
SKS[Lf
HibernateException; F0|T%!FB>%
'WOWm$2
} c^=:]^
1XZ&X]
NKMB,b
wHY;Y-(ZT
e)iVX<qb
java代码: D!-zQ`^
<Nw?9P
W35nnBU
/*Created on 2005-7-15*/ Zkz:h7GUG-
package com.adt.service.impl; @&~BGh
mDq01fU4
import java.util.List; tL3(( W"
{66vdAu&h<
import net.sf.hibernate.HibernateException; ~k J#IA
jt]+(sx
import org.flyware.util.page.Page; BHU[Rz7x
import org.flyware.util.page.PageUtil; wY=ky629
s+CWyW@
import com.adt.bo.Result; |[: `izW
import com.adt.dao.UserDAO; }8FP5Z'Cf%
import com.adt.exception.ObjectNotFoundException; xCQ<G{;C
import com.adt.service.UserManager; _&:o"""Wf
G%>[I6G
/** x7/2e{p
uu
* @author Joa p\,lbrv
*/ _I-0[w
publicclass UserManagerImpl implements UserManager { H`".L^
2.x3^/
private UserDAO userDAO; l9<+4rK2
)GR^V=o7,Y
/** m2V4nxw]Qp
* @param userDAO The userDAO to set. jK{CjfCNz
*/ Na`qA j}
publicvoid setUserDAO(UserDAO userDAO){ R<wb8iir
this.userDAO = userDAO; 57oY]NT?
} a $KM
q>
^*0;Z<_
/* (non-Javadoc) =B/^c>w2
* @see com.adt.service.UserManager#listUser 1'g?B`
.N5"IY6>
(org.flyware.util.page.Page) -Rf|p(SJ,E
*/ adxJA}K}
public Result listUser(Page page)throws 5]F9o9]T
?hwQY}
HibernateException, ObjectNotFoundException { Cf+O7Y`^
int totalRecords = userDAO.getUserCount(); kTnvD|3_!P
if(totalRecords == 0) -&HN h\
throw new ObjectNotFoundException ;lK2]
Pq`4Y
K
("userNotExist"); m t*v@'l.
page = PageUtil.createPage(page, totalRecords); @Xh4ZMyEx
List users = userDAO.getUserByPage(page); Q;Oc#
u
returnnew Result(page, users); 8ZahpB
} {1qEN_ERx
5Ut0I]h|z
} B kC(9[Ei
jb*#!m.l
5H',Bm4-
vWgh?h/ot
p@^2.O+
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 Y /wvn8~C
Mr&]RTEE
询,接下来编写UserDAO的代码: ^ZV xBQKg
3. UserDAO 和 UserDAOImpl: ;Lu}>.t
java代码: 9\"~ G)
Mc\lzq8\ 1
&hF>}O
/*Created on 2005-7-15*/ 6Qo6T][
package com.adt.dao; iffU}ce
E O}(MXS
import java.util.List; p3Gj=G
L,:U _\HQ
import org.flyware.util.page.Page; *yJb4uALB
G{s ,Y^
import net.sf.hibernate.HibernateException; $4?%Z>'
k20H|@g2
/** IAtZ-cM<
* @author Joa )XNcy"
*/ mki=.l$O
publicinterface UserDAO extends BaseDAO { Kp99y
EZ=M^0=Hpf
publicList getUserByName(String name)throws ?e ~* ,6
O35f5Kz
HibernateException; :3G9YjzC}
0(..]\p^d
publicint getUserCount()throws HibernateException; O}%=c\Pb
<Q8bn?Z
publicList getUserByPage(Page page)throws NR3IeTd
)-sEm`(`I9
HibernateException;
vdo[qk\C
ES+&e/G"ds
} @.gCeMlOf
/@OGYYH,M
'IgtBd|K>
a@X'oV`(2b
Kzmgy14o
java代码: X31k HK5F_
TX
87\W.
Wqqo8Y~fq
/*Created on 2005-7-15*/ '|+_~ZO*d
package com.adt.dao.impl; =GpLlJ`-
PK~okz4b
import java.util.List; EYQ!ELuF
K;Xn!:) V:
import org.flyware.util.page.Page; E6G^?k~q
0|U<T#t8?
import net.sf.hibernate.HibernateException; Oe=,-\&_
import net.sf.hibernate.Query; 6?Wsg`9
fY `A
import com.adt.dao.UserDAO; 6v1j*'
U]P;X~$!
/** vD*KJ3(c
* @author Joa [;b9'7j'
*/ H4pjtVBr
public class UserDAOImpl extends BaseDAOHibernateImpl 9#agI|d~
Hnaq+ _]
implements UserDAO { 1|%$ie
7,jqA"9
/* (non-Javadoc) u|Ai<2b$
* @see com.adt.dao.UserDAO#getUserByName N
Lo>"<Xb
Z,2uN!6
(java.lang.String) (thzWr6;
*/ `?>OY&(
publicList getUserByName(String name)throws hIw*dob
B U)4g[4
HibernateException { )Qo6bei!
String querySentence = "FROM user in class QR#,n@fE
(kSkbwu
com.adt.po.User WHERE user.name=:name"; ;Rt,"W)
Query query = getSession().createQuery k4|YaGhf
m:H )b{
(querySentence); LO2sP"9
query.setParameter("name", name); ffWvrY;j[
return query.list(); N$3F4b%+
} [m"X*ZF
)HmpVH
/* (non-Javadoc) }skXh_Vu4
* @see com.adt.dao.UserDAO#getUserCount() leiza?[
*/ ~p8!Kb6
publicint getUserCount()throws HibernateException { O
8fh'6
int count = 0; |ST&,a$(
String querySentence = "SELECT count(*) FROM =]"PSY7p
abF_i#
user in class com.adt.po.User"; 2{qoWys8[
Query query = getSession().createQuery aJfW75C
-V+fQGZe
(querySentence); ;<* VwXJR
count = ((Integer)query.iterate().next =EG[_i{r
c2i^dNp_
()).intValue(); QTDI^ZeuF
return count; @Wv*`
} ' E@D
AvwX 2?tc
/* (non-Javadoc) eC3ZK"oJ
* @see com.adt.dao.UserDAO#getUserByPage }b{N[
1\3n
(org.flyware.util.page.Page) 1,/oS&?E
*/ )i?wBxq'MA
publicList getUserByPage(Page page)throws rzex"}/ly
?$gEX@5h
HibernateException { Coyop#q#"{
String querySentence = "FROM user in class ZA# jw 8F
R` N-^x
com.adt.po.User"; 18`?t_8g
Query query = getSession().createQuery E0*81PS
mjw:Z,
(querySentence); ?>w%Lg{L}
query.setFirstResult(page.getBeginIndex()) >y az
.setMaxResults(page.getEveryPage()); sQ_{zOUPh
return query.list(); zi5;>Iv0}
} mO\6B7V!
avT>0b:
} U_!6pqFc
{:? -)Xq
N#UyAm<9
ptsi\ 7BG
NTn-4iJy
至此,一个完整的分页程序完成。前台的只需要调用 j#Y8h5r
Bkcs4 x
userManager.listUser(page)即可得到一个Page对象和结果集对象 :${Lm&J
f6z[k_lLN
的综合体,而传入的参数page对象则可以由前台传入,如果用 O/FQ'o1F
KI#hII[Q.
webwork,甚至可以直接在配置文件中指定。 .-o$IQsS
Xf.SJ8G
下面给出一个webwork调用示例: R[9[lQ'vR
java代码: 5` Q#2
Gz
kf
z,^baU
/*Created on 2005-6-17*/ /|>z7#?m^
package com.adt.action.user; |i|>-|`!
Bq\%]2;eo{
import java.util.List; ? 1_*ct=g9
Wx^L~[l
import org.apache.commons.logging.Log; BK-{z).)
import org.apache.commons.logging.LogFactory; C^uXJ~8
import org.flyware.util.page.Page; pE`BB{[@
h nyZXk1|
import com.adt.bo.Result; X${k
import com.adt.service.UserService; mH;\z;lyK
import com.opensymphony.xwork.Action; `i<U;?=0'
<Nkj)`%5iK
/** QupCr/Hs
* @author Joa zEa3a
*/ `~gyq>Ik2
publicclass ListUser implementsAction{ ] @IzJz"R
\[Q,>{^
privatestaticfinal Log logger = LogFactory.getLog RU@`+6j+
pvcD
61,
(ListUser.class); &t`l,]PQ=6
lh
.p`^v
private UserService userService; 2r\f!m'
%kyvtt
private Page page; Es)Kw3^a
Ut0oh
privateList users; aLG6y Vtu
%\CsP!
/* sN;xHTY
* (non-Javadoc) \QQw1c+
* T,5]EHea
* @see com.opensymphony.xwork.Action#execute() N5o jXX!l%
*/ 0<fN<iR`
publicString execute()throwsException{ meE&, {
Result result = userService.listUser(page); 3!#d&
page = result.getPage(); EdLbVrN,
users = result.getContent(); Z+E@B>D7A^
return SUCCESS; YQ;?N66
} wOn.m
V|DAw[!6N
/** iz&)FuOr
* @return Returns the page. oS, %L
*/ >DPC}@Wl
public Page getPage(){ {}~7Gi!
return page; {Q I"WFdGx
} R9^Vk*`gFU
7]62=p2R
/** KP%A0
* @return Returns the users. $O?&!8);,
*/ E&/#Ov
publicList getUsers(){ T5Yu+>3
return users; KHI-m9(
} 4uwI=U UB
VPet1hAy
/** bU7n1pzW,o
* @param page ol[
* The page to set. H)ud?vB6
*/ xhWWl(r`5
publicvoid setPage(Page page){ u%}zLwMH
this.page = page; srLXwoN[
} F8S% \i
wa5wkuS)ld
/** -X3yCK?re
* @param users `$Z:j;F
* The users to set. WRe9ki=R
*/ %
tT L
publicvoid setUsers(List users){ Q9Sh2qF^2
this.users = users; ")}^\Om
} xk7MMRb
iz.J._&
/** *2P%731n5
* @param userService B<%cqz@
* The userService to set. EyO=M~nsS
*/ 5bKM}?=L
publicvoid setUserService(UserService userService){ $SQUN*/>
this.userService = userService; 6j/g/!9c!
} xf% _HMKc
} uB_8P+h7
H`d595<=i;
@y]ek/
VKqIFM1b
#ue WU
上面的代码似乎看不出什么地方设置了page的相关初值,事实上, ,1&Pb %}
g(& hu S
可以通过配置文件来进行配置,例如,我想每页显示10条记录,那 '"qTmo!
mSdByT+dG
么只需要: Vsw]v
java代码: C9OEB6
e ?sMOBPlv
Y7vUdCj
<?xml version="1.0"?> MVP|l_2!
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork jlXzfDT
v#c'p^T
1.0//EN" "http://www.opensymphony.com/xwork/xwork- Td(eNe_4T
&6wD
1.0.dtd"> =p{55dR
79`OB##
<xwork> 1 etl:gcEC
+-2o b90_m
<package name="user" extends="webwork- :8h\x
B8.a#@R
interceptors"> &YpViC4K.
&rs
<!-- The default interceptor stack name ( f]@lNmx
Jui:Ms
--> }$%j} F{
<default-interceptor-ref BA(erf>
~?#>QN\\c
name="myDefaultWebStack"/> F \0>/
C-)mP- |8
<action name="listUser" 2~`vV'K
L)(JaZyV5
class="com.adt.action.user.ListUser"> 1V
,Mk#_
<param 7M8oI.?C|
/|s~X@%K
name="page.everyPage">10</param> 27J!oin$
<result N>
7sG(!'"
A#7/,1h\
name="success">/user/user_list.jsp</result> vbBNXy/
</action> ahICx{hK
^#( B4l!
</package> ty ESDp%
05>mR qVL
</xwork> }uR[H2D`L
R`5g#
(/gv
U80
_ck)yY?7
11VtC)
`^v=* &
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 |qs8(
5z0
*jR4OY|DXH
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。 [g<Y,0,J
r{ >`"
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 baQORU=X
=Gv*yR*]t
~%chF/H
z`}z7e'>
6.Jvqn
我写的一个用于分页的类,用了泛型了,hoho &zR\Rmpt
_ sqj~|K
java代码: &L[i"1a
+$}3=n34)
9epMw-)k
package com.intokr.util; cslZ;
y#T.w0*
import java.util.List; r1axC%
Z)&!ZlM
/** ='vD4}"j
* 用于分页的类<br> Ko|m<;LX
* 可以用于传递查询的结果也可以用于传送查询的参数<br> \OJam<hZ
* .} O@<t
* @version 0.01 8$F"!dc _
* @author cheng I1pnF61U
*/ w!dgIS$
public class Paginator<E> { d88Dyzz
privateint count = 0; // 总记录数 +0ALO%G;G"
privateint p = 1; // 页编号 _`I}"`2H
privateint num = 20; // 每页的记录数 *z'v
privateList<E> results = null; // 结果 &HQ_e$1
$PstEL
/** ?:tk8Kgf
* 结果总数 %lk^(@+ T
*/ DFkDlx
publicint getCount(){ bN\;m^xfu
return count; hp c &s
} {^D; ($lm
skm~~JM^
publicvoid setCount(int count){ 38 ]}+Bb
this.count = count; ;Rlf[](iL
} Z;O!KsJ
$Ge0<6/
/** pwH*&YU
* 本结果所在的页码,从1开始 J!Q #xs
* <z#.J]
* @return Returns the pageNo. z]2MR2W@X
*/ Oq^t[X'
publicint getP(){ Z9G4in8
return p; }a!ny
} .mHVJ5^:4\
enx+,[
/** .p=OAh<
* if(p<=0) p=1 SBy{sbx4&F
* F
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* @param p )K8^}L,
*/ +Wl]1
c/
publicvoid setP(int p){ uO>x"D5tZ:
if(p <= 0) :7M%/#Fy
p = 1; l 88n*O
this.p = p; p()q)P
} H_ a##z
M"Af_Pbx
/** **$kWbS
* 每页记录数量 -9~$Ll+2h
*/ >V?W_oM)
publicint getNum(){ ^F'~|zc"C
return num; / Xq|SO
} IgjPy5k
&pf"35ll
/** 25f[s.pv8
* if(num<1) num=1 L@'2}7N1%
*/ $Zr \$z2
publicvoid setNum(int num){ &pQ[(|=(
if(num < 1) h3bQ<?m
num = 1; 7H*,HZc@=
this.num = num; Ee_?aG
e&
} /6rQ.+|).
vz(=3C[
/** g(auB/0s
* 获得总页数 'qUM38 s
*/ 9OFH6-;6`\
publicint getPageNum(){ &.(iS
return(count - 1) / num + 1; LF`]=.Q
} CIui9XNU
u -)ED
/** QLU <%w:B
* 获得本页的开始编号,为 (p-1)*num+1 3ZC@q
#R
A
*/ ])G|U A.
publicint getStart(){ # >I_
return(p - 1) * num + 1; :@@`N_2?
} =jKu=!QPq
T+x
/J]A
/** W\($LD"X
* @return Returns the results. Yecdw'BW?
*/ {sxdDl
publicList<E> getResults(){ C=CZtjUt
return results; #D#kw*c
} C?k\5AzT
5VpqDL~d
public void setResults(List<E> results){ =`*@OJHH
this.results = results; >0[:uu,'>
} ,cxe"U
}9^'etD
public String toString(){ M)ao}m>
StringBuilder buff = new StringBuilder r;)31Tg
A9g/At_
(); 33KCO
buff.append("{"); (f^/KB=
buff.append("count:").append(count); !vSq?!y6*P
buff.append(",p:").append(p); t^Lb}A#$4
buff.append(",nump:").append(num); HY eCq9S
buff.append(",results:").append }
xA@3RT
s FJ:09L|
(results); m]*a;a'}#
buff.append("}"); N iu
|M@
return buff.toString(); N
p*T[J
} \D k >dE&I
HL]J=Gh
} pacD7'1{
|'&$VzA
5Ok3y|cEx