Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 WGjT06a\
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 'WK}T)o
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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 ._@Scd
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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 dK'?<w$
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分页支持类: &09z`*,
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java代码: Q!K@
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package com.javaeye.common.util; h<H.8.o
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import java.util.List; ^|y6oj
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publicclass PaginationSupport { L4`bGZl55
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publicfinalstaticint PAGESIZE = 30; mqgA
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privateint pageSize = PAGESIZE; =H6"\`W
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privateList items; Jj+|>(P
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privateint totalCount; s\ft:a@
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privateint[] indexes = newint[0]; @
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privateint startIndex = 0; !|6M ,Rk_
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public PaginationSupport(List items, int ,jJ&x7ra8
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totalCount){ {^>dQ+S x7
setPageSize(PAGESIZE); ({ 'I;]AQ
setTotalCount(totalCount); (sLFJ
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setItems(items); ;;rEv5 /
setStartIndex(0); HqNM3 1)
} @wO"?w(
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public PaginationSupport(List items, int ;u`zZb=,[
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totalCount, int startIndex){ gwE#,OY*
setPageSize(PAGESIZE); !G E-5 \*
setTotalCount(totalCount); -o c@$*t
setItems(items); =" Q5Z6W
setStartIndex(startIndex); {n9]ej^
} &}}c>]m
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public PaginationSupport(List items, int #\9sCnb
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totalCount, int pageSize, int startIndex){ t\44 Pu%
setPageSize(pageSize); >7%Gd-;l
setTotalCount(totalCount); F
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setItems(items); u,AZMjlF
setStartIndex(startIndex); I4'mU$)U
} p6~\U5rXm
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publicList getItems(){ heQ<%NIA"
return items; A0{ !m
} qOaI4JP@
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publicvoid setItems(List items){ 9pAklD 4
this.items = items; }^r=(
} I2G4j/c=z
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publicint getPageSize(){ ]BAM _
return pageSize; 2<&lrsh
} qK}4r5U
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publicvoid setPageSize(int pageSize){ (!kd9uV
this.pageSize = pageSize; S[!sJ-rG
} Hkq""'Mx+w
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publicint getTotalCount(){ cRYnQ{$'
return totalCount; p.{9OrH(4
} ?VC[%sjwn
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publicvoid setTotalCount(int totalCount){ ,G2]3
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if(totalCount > 0){ E.*TJ
this.totalCount = totalCount; >E*j4gg
int count = totalCount / AKWM7fI
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pageSize; jSMvZJX3n
if(totalCount % pageSize > 0) OsS5WY0H
count++; 6ww4ZH?j
indexes = newint[count]; Q'?{_
for(int i = 0; i < count; i++){ Ejc%DSG
indexes = pageSize * O'tVZ!C#J
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i; d=<"sHO
} ]ZJu
}else{ :e9}k5kdk
this.totalCount = 0; EW;R^?Z
} Y@)iPK@z
} l| 1O9I0Gd
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publicint[] getIndexes(){ vZEeb j
return indexes; t;wfp>El
} P'Q|0lB
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publicvoid setIndexes(int[] indexes){ x13t@b
this.indexes = indexes; :U^!N8i"=
} "`pI!nj
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publicint getStartIndex(){ rn1^6qy)
return startIndex; .xXe *dm%
} =,Yi" E
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publicvoid setStartIndex(int startIndex){ om$x;L6
if(totalCount <= 0) Jw%0t'0Zi
this.startIndex = 0; ^,@!L-<~(b
elseif(startIndex >= totalCount) Az+}[t
this.startIndex = indexes j3j<01rq
y*ae 5=6(
[indexes.length - 1]; z+ybtS>pZ
elseif(startIndex < 0) hrfu\cI
this.startIndex = 0; $umh&z/
else{ S\7-u\)
this.startIndex = indexes
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[startIndex / pageSize]; fhx_v^<X
} 4k9O6
} YGp8./ma<I
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publicint getNextIndex(){ 0fgt2gA33
int nextIndex = getStartIndex() + *P4G}9B|9:
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pageSize; O*MC"%T
if(nextIndex >= totalCount) gg;&a(
return getStartIndex(); O 0Fw!IQk
else RS&l68[6
return nextIndex; b!W!Vvf^x
} ByR%2_6&
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publicint getPreviousIndex(){ @eQIwz
int previousIndex = getStartIndex() - i7h!,vaK
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5
pageSize; B j!{JcM-^
if(previousIndex < 0) .ztO._J7f
return0; 5mNd5IM
else g70B22!y
return previousIndex;
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} wOH$S=Ba5,
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} _tE`W96J
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抽象业务类 r|rOIAo
java代码: Gv,_;?7lD
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/** T/NeoU3 p
* Created on 2005-7-12 c#eV!fl>&
*/ 1#H=<iJ
package com.javaeye.common.business; p|Po##E}g^
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import java.io.Serializable; >5Vv6_CI0?
import java.util.List; 7~@q#]U[
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import org.hibernate.Criteria; uW*)B_c
import org.hibernate.HibernateException; <Wgp$qt;
import org.hibernate.Session; T%kr&XsQX
import org.hibernate.criterion.DetachedCriteria; sqkk4w1#C
import org.hibernate.criterion.Projections; }?zy*yL
import a6AD`| U8
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org.springframework.orm.hibernate3.HibernateCallback; OQt_nb#z`{
import ?1\rf$l8
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org.springframework.orm.hibernate3.support.HibernateDaoS Zo}O,;(F5
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upport; 1-`Il]@?8
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import com.javaeye.common.util.PaginationSupport; 'l,ym~R
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public abstract class AbstractManager extends .t\#>Fe
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HibernateDaoSupport { "8{#R*p
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privateboolean cacheQueries = false; *c<=IcA
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privateString queryCacheRegion; G:'hT=8
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publicvoid setCacheQueries(boolean e nsou!l
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cacheQueries){ j9FG)0
this.cacheQueries = cacheQueries; y\M]\^[7
} )erI3?k
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publicvoid setQueryCacheRegion(String [
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queryCacheRegion){ 9F[k;Uw
this.queryCacheRegion = pY75S5h:
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queryCacheRegion; A.0eeX{
}
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publicvoid save(finalObject entity){ x+niY;Z E
getHibernateTemplate().save(entity); ~?l>QP|o
} IGKF&s*;{[
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publicvoid persist(finalObject entity){ KxZup\\:v
getHibernateTemplate().save(entity); ~.-o*
} #9Src\V
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publicvoid update(finalObject entity){ 'Z^-(xG,+
getHibernateTemplate().update(entity); Ct-^-XD
} Rd|#-7
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publicvoid delete(finalObject entity){ <#c/uIN
getHibernateTemplate().delete(entity); r$7zk<01
} [nL{n bli
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publicObject load(finalClass entity, F#<$yUf%
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finalSerializable id){ E'_3U5U
return getHibernateTemplate().load {,kA'Px)
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(entity, id); gK8E|f-z
} G a1B&@T
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publicObject get(finalClass entity, H Pvs~`>V
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finalSerializable id){ x^ 0MEsR
return getHibernateTemplate().get sr|afqjXD
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(entity, id); vz{Z
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} `dp]N0nz
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publicList findAll(finalClass entity){ ^p@ #
return getHibernateTemplate().find("from 57nSyd]PR
(fSpY\JPI
" + entity.getName()); .=I:cniw\r
} 71)DLGL
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publicList findByNamedQuery(finalString 5!tiu4LU
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namedQuery){ GxFmw:
return getHibernateTemplate J%|n^^ /un
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().findByNamedQuery(namedQuery); KUR9vo
} Y2Z<A(W
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publicList findByNamedQuery(finalString query, L("zS%qr
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finalObject parameter){ Uu}a! V
return getHibernateTemplate W.|r=
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().findByNamedQuery(query, parameter); xoT|fgb
} 0\/cTNN
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publicList findByNamedQuery(finalString query, MPS{MGVjbJ
IN{ 1itE
finalObject[] parameters){ q>n0'`q
return getHibernateTemplate =
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().findByNamedQuery(query, parameters); 1G6 %?Iph
}
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publicList find(finalString query){ Y<h [5
return getHibernateTemplate().find BZdryk:S
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(query); $t1XoL
} >sfH[b
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publicList find(finalString query, finalObject !+F6Bf
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parameter){ ){_D
return getHibernateTemplate().find I7Uj<a=(q
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(query, parameter); `3QAXDWE
} N.l\2S}
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public PaginationSupport findPageByCriteria Wwf],Ya
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(final DetachedCriteria detachedCriteria){ E\GD hfTQ
return findPageByCriteria Y,
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); v})-:
} /8s+eHn&%
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public PaginationSupport findPageByCriteria )]W|i9
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(final DetachedCriteria detachedCriteria, finalint bq}hj Cy
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startIndex){ {,Py%.vvR
return findPageByCriteria #$dk
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(detachedCriteria, PaginationSupport.PAGESIZE, /HiRbwQK#
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startIndex); >
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} 0IP5&[-P
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public PaginationSupport findPageByCriteria <"SOH;w
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(final DetachedCriteria detachedCriteria, finalint eX1<zzd
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pageSize, L)!9+!PKD
finalint startIndex){ SZ*Nr=X
return(PaginationSupport) 1(;_1@P
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getHibernateTemplate().execute(new HibernateCallback(){ #+<"`}]N
publicObject doInHibernate u6pfc'GG g
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(Session session)throws HibernateException { 3EHn}#+U
Criteria criteria = w:0=L`<Eu
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detachedCriteria.getExecutableCriteria(session); ujt0?DM
int totalCount = pod=|(c
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((Integer) criteria.setProjection(Projections.rowCount 6')pM&`t
m&36$>r=
()).uniqueResult()).intValue(); T]#S=]G
criteria.setProjection gFx2\QV
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(null); HLa3lUo
List items = /%P|<[<
[
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criteria.setFirstResult(startIndex).setMaxResults e=yQFzQT)
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(pageSize).list(); ;]/emw=a
PaginationSupport ps = ZjEc\{ s
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new PaginationSupport(items, totalCount, pageSize, ?df*Y5I2
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startIndex); VPAi[<FzOG
return ps; =jWcD{;1I}
} 2(<2Gnpl
}, true); e{*-_j"I
} ROv(O;.Ty
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public List findAllByCriteria(final B]""%&! O
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DetachedCriteria detachedCriteria){ }ob&d.XZ
return(List) getHibernateTemplate DF>LN%a~
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().execute(new HibernateCallback(){ M$O*@])
publicObject doInHibernate ^^O @ [_
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(Session session)throws HibernateException { 3kc.U
Criteria criteria = q3CcXYY
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detachedCriteria.getExecutableCriteria(session); #2XX [d%
return criteria.list(); N3Yf3rK
} 2EU((Q`>=(
}, true); D; @nrj`.
} fs:%L
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public int getCountByCriteria(final e)#O-y
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DetachedCriteria detachedCriteria){ 3t*e|Ih&j5
Integer count = (Integer) 6G^x%s
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getHibernateTemplate().execute(new HibernateCallback(){ 0pC}+
+
publicObject doInHibernate $CXMeY{tOo
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(Session session)throws HibernateException { .:`+4n
Criteria criteria = "IjCuR;#
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detachedCriteria.getExecutableCriteria(session); FS(bEAk}
return 'pa>;{
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criteria.setProjection(Projections.rowCount vZ
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()).uniqueResult(); b,k%n_&n
} %/K'VE6pb
}, true); &{x%"Aq/
return count.intValue(); {#Lj,o
} _`H2CXGg
} }^}fx [
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用户在web层构造查询条件detachedCriteria,和可选的 {Xc^-A[~
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 w`N|e0G@
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PaginationSupport的实例ps。 u(Y! _
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ps.getItems()得到已分页好的结果集 o:p6[SGd
ps.getIndexes()得到分页索引的数组 tiTJ.uz6
ps.getTotalCount()得到总结果数 RW?F{Jy{
ps.getStartIndex()当前分页索引 wfecM(
ps.getNextIndex()下一页索引 |<Cz#|
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ps.getPreviousIndex()上一页索引 )YKnFSm
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 gJ;
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,尤其是上面的示例代码,让我着实觉得该对我原来的分页查询做 efc<lSUR
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一下代码重构了。 TL29{'4V
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我把原本我的做法也提供出来供大家讨论吧: ;2NJkn9t
j56#KNAha
首先,为了实现分页查询,我封装了一个Page类: 4(h19-V
java代码: B8f BX!u/
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/*Created on 2005-4-14*/ e[Tu.$f-
package org.flyware.util.page; +b9gP\Hke
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/** pG|+\k/B
* @author Joa fP:n=A{
* lBYc(cr
*/ mMz^I7$
publicclass Page { csEF^T-
pX\Y:hCug
/** imply if the page has previous page */ zZhAH('fG
privateboolean hasPrePage; ||}k99y +
rt_k }
/** imply if the page has next page */ |4slG
privateboolean hasNextPage; ^57G]$Q
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/** the number of every page */ 0xSWoz[i6~
privateint everyPage; $=IJ-_'o
ytWTJ>L
/** the total page number */ <{z*6FM!'
privateint totalPage; vFz#A/1
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/** the number of current page */ ; qQ* p
privateint currentPage; FC+}gJ(q
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/** the begin index of the records by the current 8iB}gHe9
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query */ [!<W{ ($5
privateint beginIndex; q2pq~LI
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/** The default constructor */ )6t=Bel
public Page(){ BDO]-y
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} iE}Lw&x
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/** construct the page by everyPage <
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* @param everyPage .#4;em%7
* */ q[wVC
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public Page(int everyPage){ |})7\o
this.everyPage = everyPage; w]%|^:
} k*U(ln
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/** The whole constructor */ a%IJ8t+mn
public Page(boolean hasPrePage, boolean hasNextPage, )J"*[[e
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int everyPage, int totalPage, .*x |TPv{
int currentPage, int beginIndex){ 1 p|h\H
this.hasPrePage = hasPrePage; G<MX94?
this.hasNextPage = hasNextPage; T\
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this.everyPage = everyPage; l>J>?b=x"[
this.totalPage = totalPage; x=7qC#+)
this.currentPage = currentPage; <*vWcCS1
this.beginIndex = beginIndex; g?mfpw Zj
} hE9UWa.Q>
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/** B<
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* @return Vt[Kr
* Returns the beginIndex. _P:}]5-|
*/ j@98UZ{g\
publicint getBeginIndex(){ oA;> z
return beginIndex; 'A#bBn,|
} v?)u1-V0
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/** T 8.
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* @param beginIndex k/`WfSM\.
* The beginIndex to set. ,5
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*/ #% 1|$V*:
publicvoid setBeginIndex(int beginIndex){ Pi!3wy
this.beginIndex = beginIndex; PIthv[F
} vr$zYdV>
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/** PAcbC|y
* @return 4_i6qu(4
* Returns the currentPage. _ft)e3Gf
*/ _l$1@
publicint getCurrentPage(){ 8#_"WzDw
return currentPage; yaw33/iN
} $&@etsW0/
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/** D$vP&7pOr4
* @param currentPage yJMHm8OB7
* The currentPage to set. }vof| (Yh
*/ K;NaiRP#k
publicvoid setCurrentPage(int currentPage){ MB#KLTwnT
this.currentPage = currentPage; -gzY~a
} |E7)s;}D
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/** Zi4Ektj2
* @return 4hLv"R.
* Returns the everyPage. D,<#pNO_
*/ k@RIM(^t
publicint getEveryPage(){ &l| :1
return everyPage; J nzI-
y
} jaOt"iU.B
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/** GO|EeM!iB
* @param everyPage j\^u_D
* The everyPage to set. `JrvD
*/ C\d5t4s
publicvoid setEveryPage(int everyPage){ rjJ-ZRs\
this.everyPage = everyPage; EvJ"%:bp
} e|~s'{3
*K}j>A
/** X"z!52*3]
* @return ;^cc-bLvF
* Returns the hasNextPage. 9>1
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*/ S$egsK"~
publicboolean getHasNextPage(){ "p[FFg
return hasNextPage; rQ!X
} aDreN*n
wwI'n*Q'$
/** _;x7vRWmN
* @param hasNextPage (9X>E+0E
* The hasNextPage to set. {+.ai8
*/ SyWLPh
publicvoid setHasNextPage(boolean hasNextPage){ g'Id31r'
this.hasNextPage = hasNextPage; Dqu][~oQ
} n!>#o1Qr
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/** nOE 1bf^l
* @return 6?X)'
* Returns the hasPrePage. %!_%%p,f
*/ hG3p"_L
publicboolean getHasPrePage(){ J91O$szA
return hasPrePage; 3|FZ!8D
} k.dQ;v}
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/** C*f3PB=H_
* @param hasPrePage KW[Jft
* The hasPrePage to set. g\n0v~T+
*/ dAZh# i[
publicvoid setHasPrePage(boolean hasPrePage){ ,svj(HP$
this.hasPrePage = hasPrePage; O(Tdn;1
} '+Gy)@c
xqAXfJ.
/** VIi/=mO]
* @return Returns the totalPage. yN Bb(!u
* i7RW8*
*/ V`7^v:
publicint getTotalPage(){ E{-W#}#
return totalPage; ?R;K`f9<
} DwL4?!E
:le"FFfk
/** ~{O9dEI
* @param totalPage |4XR [eX
* The totalPage to set. BW61WH?
*/ Q;3v ]h_
publicvoid setTotalPage(int totalPage){ xg>AW Q
this.totalPage = totalPage; ZMVQo-=
} iQI$Y]Y7
b[MdA|C%j
} 2EdKxw3$]
o=,q4;R'
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GG}(*pOr
上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 _c W(R,i
qU1^ K
个PageUtil,负责对Page对象进行构造: 7JedS
java代码: ``:AF:
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/*Created on 2005-4-14*/ N9M''H*VS
package org.flyware.util.page; S4jt*]w5b
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import org.apache.commons.logging.Log; A-"}aCmik
import org.apache.commons.logging.LogFactory; ZL-YoMHc+_
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/** *$KUnd-T
* @author Joa YJ&K0%R
* Eoj 2l&\
*/ &dino
publicclass PageUtil { ||lI_B
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privatestaticfinal Log logger = LogFactory.getLog 8%$Vj
ww]^H$In
(PageUtil.class); r*'X ]q|L+
q]\bJV^/U
/** =!G3YZ
* Use the origin page to create a new page jQKlJi2xu
* @param page fDn| o"
* @param totalRecords ?Q`Sx
* @return t ._PS3
*/ Y!kz0([
publicstatic Page createPage(Page page, int WJ{hta
l
@hXQ/
totalRecords){ Ch1+YZG
return createPage(page.getEveryPage(), G n_AXN
%r<c>sFJN
page.getCurrentPage(), totalRecords); o|s JTY
} pX:FXzYQ
OZF^w[ `w
/** +7jr ]kP9
* the basic page utils not including exception 2o`a^'Iw
;
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handler 5pBQ~m3
* @param everyPage gDw:Z/1X`
* @param currentPage r|XNS>V ,$
* @param totalRecords Dj<]eG]
* @return page pr|P#mc"J
*/ ZD9UE3-
publicstatic Page createPage(int everyPage, int D&{7Av
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currentPage, int totalRecords){ AQ!FJ(X(
everyPage = getEveryPage(everyPage); [mSK!Y@u
currentPage = getCurrentPage(currentPage); N#;k;Z'iL
int beginIndex = getBeginIndex(everyPage, w$9aTL7
uv++Kj!
currentPage); h^P>,dy0
int totalPage = getTotalPage(everyPage, web=AQ5I4
:<OInKE>Cx
totalRecords); zX-6]j;
boolean hasNextPage = hasNextPage(currentPage, Phsdn`,
7-M$c7S
totalPage); g8yWFqE!T
boolean hasPrePage = hasPrePage(currentPage); ZDZPJp,
+w-UK[p
returnnew Page(hasPrePage, hasNextPage, g1Q^x/
everyPage, totalPage, v hUn3|
currentPage, um@RaU
x@F"ZiYD@O
beginIndex); }b+tD3+
} K?_4|
)*@Oz
privatestaticint getEveryPage(int everyPage){ XelY?Ph,,
return everyPage == 0 ? 10 : everyPage; td@F%*
} ,.`";='o
% Ke:%##Y
privatestaticint getCurrentPage(int currentPage){ :\Z;FA@g(g
return currentPage == 0 ? 1 : currentPage;
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} G?)vqmJ%
YF=@nR$_~j
privatestaticint getBeginIndex(int everyPage, int
;p"G<n
=5E G}@
currentPage){ Xc2Oa
return(currentPage - 1) * everyPage; LSQ2pB2V
} [8/E ;h
cO2
.gQo'
privatestaticint getTotalPage(int everyPage, int }XCHoB
Ys10r-kDS
totalRecords){ vN%zk(?T
int totalPage = 0; EA4aZ6%
`j088<?j
if(totalRecords % everyPage == 0) rMqWXGl`(
totalPage = totalRecords / everyPage; {A4"KX(U
else \GeUX<Fl
totalPage = totalRecords / everyPage + 1 ; 8#S|jBV
tFvti5
return totalPage; TL+a_]3@
} ARW|wXhyf
4J2NIFZ
privatestaticboolean hasPrePage(int currentPage){ 3e"_R
return currentPage == 1 ? false : true; !3K6ew>Sf
} qFmvc
8vB~1tl;
privatestaticboolean hasNextPage(int currentPage, }U'fPYYi8
A>^\jIB>
int totalPage){ 'DlY8rEGP
return currentPage == totalPage || totalPage == K z !-w
v\:>}
<gc
0 ? false : true; _s!(9
} FsZF>vaV
DY?`Y%"
RNuOwZ1m
} ,U2
/J
Zb`}/%\7
J'y*;@4l^:
BCF-lrZ&
r4jW=?|
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 <FmrYwt
[V()7
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 ?s(%3_h
wQ[~7 ,o
做法如下: BOn2`|oLuF
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 !1!;}uzt
5KU}dw>*g
的信息,和一个结果集List: @!^c@
java代码: MuYr?1<q
:*#AJV)
+Tde#T&[
/*Created on 2005-6-13*/ L.lmbxn
package com.adt.bo; _S/bwPj|~y
x;lIw)Ti
import java.util.List; uXW<8(
%W
?Jm/v%0O
import org.flyware.util.page.Page;
=w0Rq~
aDR<5_Yb
/** iSo+6gu
* @author Joa S1wt>}w0$
*/ Lie\3W
publicclass Result { g=Q#2/UQ<
9*RfOdnNe
private Page page; $@+\_f'bU>
?s #DD,
private List content; P~iu|j
9mwL\j
/** [3;J,P=&
* The default constructor zm\=4^X
*/ eI; %/6#
public Result(){ >Be PE(k
super(); =:v\}/
} S*?'y
8Z:NT_Ss
/** .
[+ObF9=
* The constructor using fields /"tVOv#
* 0FsGqFt
* @param page CT3wd?)z`
* @param content -#j-Zo+<
*/ KnbT2
public Result(Page page, List content){ e(x1w&8dB
this.page = page; 1wuLw Ad
this.content = content; 1$?O5.X:
} V/$qD
52/^>=t
/** :e ?qm7 cB
* @return Returns the content. }&d]Uv/4
*/ ^4x(a&
publicList getContent(){ 20d[\P(.
return content; \=v7'Hp
} LR]P?
0XSZ3dY&+
/** @fRB0m"3
* @return Returns the page. 0^*4LM|z
*/ s{x2RDAt
public Page getPage(){
r75,mX
return page; \;I%>yOIu
} #JYv1F
fxXZ^#2wX
/** FGG Fi(
* @param content zPWG^
* The content to set. x,@cU}D
*/ @sav8]
public void setContent(List content){ bT,]=h"0
this.content = content; vi["G7
} &sh
%]o8
ox{)O/aj
/** 0qnToV;
* @param page zK(9k0+s
* The page to set. @ T'!;)
*/ epJVs0W
publicvoid setPage(Page page){ &`0y<0z
this.page = page; BOrfKtG\
} QB'-`GwL
} Pan^@B=Q
Uxn_nh
=PP]LDlJs
%L=roqz
F/tBr%RV
2. 编写业务逻辑接口,并实现它(UserManager, ,jQkR^]j-
y;keOI!
UserManagerImpl) E[/<AY^@!z
java代码: ,6~c0]/
o_t2
Z
cT`x,2
/*Created on 2005-7-15*/ D*|h
c
package com.adt.service; e57}.pF^
`E8m>q Ss
import net.sf.hibernate.HibernateException; ,oT?-PC$z
l"*qj#FD
import org.flyware.util.page.Page; T12?'JL^r
.!\y<9
import com.adt.bo.Result; B%6>2S=E
&1ASWllD
/** T#DJQ"$
* @author Joa 'C]zB'H=
*/ &dp(CH<De
publicinterface UserManager { ;-~Wfh+
w1KLQd:yq
public Result listUser(Page page)throws 1 9$ufod
sycN
HibernateException; z'O$[6m6
KXL]Qw FN
} TW(rK&
)a.w4dH
$2A%y14
1`Cr1pH
(~?P7RnU%
java代码: rV<yM$IA
G5|xWeNgA
1y$Bz?4
/*Created on 2005-7-15*/ K
4j'e6
package com.adt.service.impl; kG[u$[B
\m1r(*Ar
import java.util.List; HDvj{
sw6]Bc
import net.sf.hibernate.HibernateException; )}\jbh>RH
(NyS2`
import org.flyware.util.page.Page; \9geDX9A
import org.flyware.util.page.PageUtil; {wih)XNY
(Gf1#,/3~
import com.adt.bo.Result; 51;V#@CsQ
import com.adt.dao.UserDAO; \`;FL\1+W
import com.adt.exception.ObjectNotFoundException; M&Sjo' ( .
import com.adt.service.UserManager; _Ft4F`pM
tu#VZAPW@
/** r"x|]nvg^
* @author Joa m]R< :_
*/ <%#M&9d)E
publicclass UserManagerImpl implements UserManager { w(U-6uA
%*>=L$A
private UserDAO userDAO; j!B+Q
8fKt6T
/** $`(}ygmP
* @param userDAO The userDAO to set. 8G;
t[9
*/ cod__.
publicvoid setUserDAO(UserDAO userDAO){ ~cbq5||
this.userDAO = userDAO; ^s\(2lB\F
} 5"%r,GM U
7pH(_-TF
/* (non-Javadoc) bccJVwXv
* @see com.adt.service.UserManager#listUser UX}ZE.cV
P95U{
(org.flyware.util.page.Page) "toyfZq@
*/ sXDS_Q
public Result listUser(Page page)throws +[:"$?J
58\Rl
HibernateException, ObjectNotFoundException { J3KY?,g3O_
int totalRecords = userDAO.getUserCount(); oXRmnt
if(totalRecords == 0) 3%{A"^S=}
throw new ObjectNotFoundException 6+u}'mSj8
N3
.!E|
("userNotExist"); .Qm"iOyM
page = PageUtil.createPage(page, totalRecords); Ox7v*[x'
List users = userDAO.getUserByPage(page); CMB:%
returnnew Result(page, users); 3[B*l@}j
} G,B?&gFX
~ibF M5m
} TQ?#PRB
n6/f an;
Y_+
SA|s
!j{CuA/
u7[pLtOwN
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 IYLZ
+>
LaclC]yLU
询,接下来编写UserDAO的代码: 2Q}7fht
3. UserDAO 和 UserDAOImpl: L$SMfx
java代码: AxEc^Cof
{d,?bs)
w]}f6VlEl
/*Created on 2005-7-15*/ $D}"k!H
package com.adt.dao; 3
&Sp@,
$7Cgo &J
import java.util.List; 2
^oGwx @
pu#[pa
import org.flyware.util.page.Page; TVYz3~m
QAi1,+y]7w
import net.sf.hibernate.HibernateException; .+HcA x{/2
**n y!
/** 1U'ZVJ5bpK
* @author Joa UG # X/%p
*/ j$mz3Yk
publicinterface UserDAO extends BaseDAO { zC#%6@P\
6m@0;Ht
publicList getUserByName(String name)throws ]q&tQJ/Fa
EWO /u.z
HibernateException; c@9##DPn
oBC]UL;8xJ
publicint getUserCount()throws HibernateException; 6^ab@GrN\
>x*)GPDa
publicList getUserByPage(Page page)throws )T/J
8 ip^]
HibernateException; "O``7HA}
NN mM#eB:4
} ~U3Seo }
o[oqPN3$Y
##GY<\",;
^obC4(
Fv A8T2-v
java代码: e,"FnW
w,/6B&|
J
3B`Krh
/*Created on 2005-7-15*/ fdLBhe#9M
package com.adt.dao.impl; pZjpc#*9N
1fR P1
import java.util.List; ,\x$q'
C/)`<b(
import org.flyware.util.page.Page; x9D/s`!
|Qr:!MA
import net.sf.hibernate.HibernateException; AOAO8%|I
import net.sf.hibernate.Query; >4c` UW
d>/Tu_ y
import com.adt.dao.UserDAO; |EEi&GOR(y
cWM:
/** YXRjx.srf
* @author Joa o[^Q y(2~
*/ (0}j]p'w
public class UserDAOImpl extends BaseDAOHibernateImpl R>HY:-2
[8z&-'J=
implements UserDAO { s[T{c.F
@ZG>mP1Vo
/* (non-Javadoc) ]'UgZsJ
* @see com.adt.dao.UserDAO#getUserByName U6c@Et ,
[<S^c[47U
(java.lang.String) SBL+e]P
*/ m9!DOL1pl
publicList getUserByName(String name)throws Ld~ q1*7J
Wn~ZA#
HibernateException { bw5T2wYZ
String querySentence = "FROM user in class S<pkc8
mLaCkn
com.adt.po.User WHERE user.name=:name"; $L\@da?
Query query = getSession().createQuery tR;{.
&mdB\Y?^
(querySentence); =x#&\ui
query.setParameter("name", name); Y/D-V
return query.list(); 7_%2xewV|
} s`1^*Dl%+
>f%, `r
/* (non-Javadoc) 9rS,?
* @see com.adt.dao.UserDAO#getUserCount() nALnB1
*/ =y<0UU
publicint getUserCount()throws HibernateException { Km"&mT $
int count = 0; *m&%vj.Kc
String querySentence = "SELECT count(*) FROM 63C(Tp"
0Az/fzJlz
user in class com.adt.po.User"; gmDR{loX
Query query = getSession().createQuery j.B>v\b_3
8t=3
(querySentence); O{u[+g
count = ((Integer)query.iterate().next *v&*% B
=]d^3bqN
()).intValue(); =hhvmo
return count; ~QCA -Yud
} xU:4Y0y8
wE4;Rk1
/* (non-Javadoc) <p/MyqZf
* @see com.adt.dao.UserDAO#getUserByPage Ko+al {2
<r3Jf}%tT
(org.flyware.util.page.Page) dE GX3 -
*/ +N8aq<l
publicList getUserByPage(Page page)throws ftaBilkjp
ydup)[n
HibernateException { N3Z@cp
String querySentence = "FROM user in class cd+^=esSO
k% NrL@z
com.adt.po.User"; ?b"Vj+1:x
Query query = getSession().createQuery b|6 !EGh
q}sK
(querySentence); BCBU b
query.setFirstResult(page.getBeginIndex()) qw2)v*Fn
.setMaxResults(page.getEveryPage()); |@ *3^'
return query.list(); zhjJ>d%w
} Rf?%Tv0\
1\IZcJ {
} ?yf_Dt
p7$3`t6u
*W%'Di
b*`fLrqV.
#w;;D7{@m
至此,一个完整的分页程序完成。前台的只需要调用 W8VO)3nmD
?R282l
userManager.listUser(page)即可得到一个Page对象和结果集对象 ET3,9+Gj
V_lGj
的综合体,而传入的参数page对象则可以由前台传入,如果用 U1jSUkqb
GZS{&w!
webwork,甚至可以直接在配置文件中指定。 [WYJrk.
m|mG;8}pI
下面给出一个webwork调用示例: <ZV7|'^
java代码: ~T7\8K+ $
a}w&dE$!-
F=:c5z
/*Created on 2005-6-17*/ pLPd[a
package com.adt.action.user; ?`"<DH~:0B
&*jixqzvn
import java.util.List; %uW<
..aK sSm(
import org.apache.commons.logging.Log; OoSa95#x
import org.apache.commons.logging.LogFactory; LPMb0F}"5
import org.flyware.util.page.Page; `!_? uT
eiOi3q
import com.adt.bo.Result; \wTW?>oZ
import com.adt.service.UserService; yG4 MUf6
import com.opensymphony.xwork.Action; aC4m{F[
9a-]T=5Ee
/** oR7 7`
* @author Joa /lru"R D
*/
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publicclass ListUser implementsAction{ |]I#CdO
^T=5zqRD
privatestaticfinal Log logger = LogFactory.getLog Y[T J;O!R
fq{I$syY
(ListUser.class); 6mX: =Q
X+\0%|
private UserService userService; 8`6
LMQ
1/!nV
private Page page; lf}?!*V`+
ayHn_
privateList users; 5t TLMZ `o
L{zamVQG
/* 4U:DJ_GN
* (non-Javadoc) dnk1Mu<
* VB}P Ng
* @see com.opensymphony.xwork.Action#execute() N{|[R
*/ r*xq(\v
publicString execute()throwsException{ =xl7vHn7
Result result = userService.listUser(page); A-}PpH~.Z
page = result.getPage(); ^BQ>vI'.4
users = result.getContent(); *'s&/vEy
return SUCCESS; @b4b{d5[
} MI?]8+l
J*/$ywI
/** Ti /;|lP@
* @return Returns the page. k:@a[qnY
*/ l^)o'YS y
public Page getPage(){ }6F_2S3c
return page; "bLP3
} "~B~{ _<j
r@\,VD6J
/** @DRfNJ}
* @return Returns the users. m/SJ4op$
*/ N. ItyV
publicList getUsers(){ yN%3w0v
return users; 1v+JCOy
} `kI?Af*;v
56/.*qa
/** ,K"r:)\
* @param page 1==P.d(
* The page to set. vy>];!Cu
*/ eG a#$x?.
publicvoid setPage(Page page){ \3J+OY
this.page = page; Y0R\u\b
} P*?d6v,r
x0N-[//YV
/** +Y_Q?/M@8
* @param users HPv&vdr3
* The users to set. k:&?$
*/ AIIBd
publicvoid setUsers(List users){ I_R5\l}O+D
this.users = users; o+PQ;Dl
} xF\}.OfWG
b6rzHnl{
/** z/Mhu{ttL
* @param userService ;@h'Mb
* The userService to set. IeqWR4Y
*/ )j)y5_m
publicvoid setUserService(UserService userService){ MZ >0K
this.userService = userService; q329z>
} a!SR"3 k
} +3~Gc<OO
Gx~"iM
soFvrl^Ql+
~Sn5;g8+\
Cz$Hk;3\6
上面的代码似乎看不出什么地方设置了page的相关初值,事实上, [5}cU{M
+w_MSj#P
可以通过配置文件来进行配置,例如,我想每页显示10条记录,那 vh:UXE lm
X7imUy'.
么只需要: @ B}c4,
java代码: &j
wnM
CU7iva
*cb
D&R\
<?xml version="1.0"?> 3>:zo:;
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork MFCbx>#
]ZU:%Qhu
1.0//EN" "http://www.opensymphony.com/xwork/xwork- S|=rF<]my
O
#p)~V8~
1.0.dtd"> Rzn 0-cG
hoSU`X
<xwork> %3@RZe
J T0,Z
<package name="user" extends="webwork- xYzcV%-Pm
~$TE
interceptors"> /hA}9+/
TnZc.
<!-- The default interceptor stack name jT wM<?
v=yI#5
--> [XY:MUe
<default-interceptor-ref =O}%bZ)Q
L{o >D"
name="myDefaultWebStack"/> DlQ[}5STF
)4o=t.O\K
<action name="listUser" a\HtxR8L
?-6x]l=]
class="com.adt.action.user.ListUser"> 0I
ND9h.%
<param BR0p0%
szM=U$jKq
name="page.everyPage">10</param> ah&plaVzC
<result L}sm R,
1PT_1[eAR
name="success">/user/user_list.jsp</result> (w7cdqe
</action> q_m#BE;t
uBL~AC3>O
</package> f^yLwRUD
fU){]YP
</xwork> uzn))/"
&V,-W0T_
BOl$UJ|K
vGLb2Q
yKk,);
t BXsWY{
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 "=5vgg3
"lnk
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。
] !*
cK}
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 rQQPs\o
b<8J ;u<
[8J}da }
9QM"JEu@
0R!}}*Ee>q
我写的一个用于分页的类,用了泛型了,hoho V/[,1W[B
fm2M i~}0
java代码:
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=rtA{g$)+
h,jAtL!
package com.intokr.util; X72X:"
OQb9ijLeK
import java.util.List; Chi<)P$^
LkbvA
/** RlPByG5K
* 用于分页的类<br> g1!L.
On
* 可以用于传递查询的结果也可以用于传送查询的参数<br> CzsY=DBH=
* oP`M\KXau
* @version 0.01 N %/DN
* @author cheng _w,0wn9N$
*/ s\1_-D5]Z
public class Paginator<E> { !5 :[X vI#
privateint count = 0; // 总记录数 ob5nk^y
privateint p = 1; // 页编号 Ol5xyj
privateint num = 20; // 每页的记录数 qN,FX#DP
privateList<E> results = null; // 结果 %+W
>+xRb
Z1lF[d,f;
/** JY8"TQ$x
* 结果总数 WM l ^XZO
*/ ]SR`96vG
publicint getCount(){ 4g^+y.,r_f
return count; tNf" X!
} : )*Ge3
[k{iN1n
publicvoid setCount(int count){ r{jD,x2
this.count = count; EuA<{%i
} `-YSFQ~O,
/g7?,/vnZ
/** o[ W3/
* 本结果所在的页码,从1开始 +\$|L+@Z
* l%5%oN`4
* @return Returns the pageNo. ]@}BdMlHp
*/ ?v~3zHK
publicint getP(){ q;~>h
return p; R'HA>?D
} 0BD((oNg
;<R_j%*
/** O}!@28|3"
* if(p<=0) p=1 To?
bp4
* >^HTghgRD
* @param p y%l#lz=6
*/ eyjUNHeh#
publicvoid setP(int p){ [t)i\ }V
if(p <= 0) ,T[
+omo
p = 1; {
4{{;
this.p = p; BtApl)q#
} Z*3}L
?^5*[H
/** ?G w89r
* 每页记录数量 XB 7^Ka
*/ y.<Y]m
publicint getNum(){ / {~h?P}
return num; ]}y'3aW
} [
[CXMbD`*
]arskmB]
/** 4ux5G`oL
* if(num<1) num=1 }Cg~::,"
*/ agD.J)v\
publicvoid setNum(int num){ `I{Q,HQ7
if(num < 1) >g2.z>
num = 1; >iJuR.:OO
this.num = num; umn^QZ,
} t+q`h3
l);8y5
/** :[03upyS
* 获得总页数 E NjD~ S
*/ X;>} ;LiK
publicint getPageNum(){ .w)t<7 y
return(count - 1) / num + 1; AE
_~DZ:%c
} +[`%b3N k
0E1)&f
/** >L4$DKO
* 获得本页的开始编号,为 (p-1)*num+1 bOKNWI
*/ B(dL`]@Xm
publicint getStart(){ FR"^?z?}p
return(p - 1) * num + 1; KVy5/A/8c
} 5C?1`-&65V
ir#^5e@
/** "r+<=JU>OV
* @return Returns the results. h_!"CF<n
*/ S}O\<6&
publicList<E> getResults(){ eO G%6C%a
return results; CU_06A|}
} .x%SbG<k{
oFp&j@`k8j
public void setResults(List<E> results){ --sb ;QG
this.results = results; fh<G&E8
p
} k({8C`&tK/
YfKty0
public String toString(){ $0t
%}DE
StringBuilder buff = new StringBuilder [NcOk,
;0gpS y$#
(); N/VIP0Kb
buff.append("{"); )`-]nMc
buff.append("count:").append(count); 4[q *7m
buff.append(",p:").append(p); =T]OYk
buff.append(",nump:").append(num); &@-glF5
buff.append(",results:").append 'h6RZKG T
_3S{n=9
(results); V
""
buff.append("}"); _I!&w!3oM
return buff.toString(); *Rd&4XG
} 6 -}gqkR
[4e5(!e
} &EOh}O<
{9MYEN}FO
r
N7"%dx