Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 :oXSh;\
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 ]bJz-6u#:
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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 oX;.v9a
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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 HJ]xZ83pC
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分页支持类: bAPMD
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java代码: 7-``J#9=
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package com.javaeye.common.util; E=N$JM
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import java.util.List; g#=<;X2
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publicclass PaginationSupport { st;iGg
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publicfinalstaticint PAGESIZE = 30; GLn=*Dh#
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privateint pageSize = PAGESIZE; 3)y1q>CQf
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privateList items; q1T)H2S
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privateint totalCount; s`jlE|jtN
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privateint[] indexes = newint[0]; {+WBi(=W
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privateint startIndex = 0; ryVYY>*(K
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public PaginationSupport(List items, int V
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totalCount){ t,?,T~#9
setPageSize(PAGESIZE); q<
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setTotalCount(totalCount); \ZZ6r^99
setItems(items); 5c` ;~
setStartIndex(0); . vb##D
} -N*[f9EJB
m ol,iM*l
public PaginationSupport(List items, int zr/v .$<
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totalCount, int startIndex){ 1zPS#K/3
setPageSize(PAGESIZE); @."K"i'Bl
setTotalCount(totalCount); w.q`E@ T*
setItems(items); =&z+7Pe[
setStartIndex(startIndex); 2y
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} &VGV0K3Dp
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public PaginationSupport(List items, int bzFac5n)Q
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totalCount, int pageSize, int startIndex){ DK74s
setPageSize(pageSize); e Ucbe33
setTotalCount(totalCount); h mRmU{(Y
setItems(items); pi?/]}:
setStartIndex(startIndex); p^pd7)sBr
} M0w Uis:`
= LNU%0m
publicList getItems(){ e,JBz~CK*w
return items; l+9RPJD/:
} ZAr6RRv ^
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publicvoid setItems(List items){ ,)1C"'
this.items = items; SE+hB
} {Dpsr` &
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publicint getPageSize(){ LP"g(D2'n
return pageSize; /o9it;
} NV*
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publicvoid setPageSize(int pageSize){ <=NnrZOF
this.pageSize = pageSize; _d]{[&
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} 1kvX#h&V
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publicint getTotalCount(){ 5-X$"Z|@
return totalCount; K=N&kda
} 6TW<,SM
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publicvoid setTotalCount(int totalCount){ :^]Po$fl
if(totalCount > 0){ $5i\D
rs
this.totalCount = totalCount; 9WG=3!-@
int count = totalCount / ,/?J!W@m
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pageSize; $mPR)T
if(totalCount % pageSize > 0) uOv<*Jld*
count++; KR( apO
indexes = newint[count]; PEI$1,z
for(int i = 0; i < count; i++){ =FzmifTc
indexes = pageSize * 8xLQ"
l+"
*|y'%y
i; ww{k_'RRJ
} FEk9a^Xyx
}else{ Xex7Lr&
this.totalCount = 0; X%YZQc9
} g$uiwqNA%
} wO,qFY
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publicint[] getIndexes(){ jr`T6!\
return indexes; ]Ozz"4Z
} E{Wn&?i>A
@ym:@<D
publicvoid setIndexes(int[] indexes){ nk|(cyt)
this.indexes = indexes; vFe=AY<Rt|
} t\/H. Hb
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publicint getStartIndex(){ (d&" @
return startIndex; 4BMu0["6|s
} wo&IVy@s$
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publicvoid setStartIndex(int startIndex){ (f&V 7n
if(totalCount <= 0) :$G^TD/n
this.startIndex = 0; :rr<#F
elseif(startIndex >= totalCount) zu}uW,XH-
this.startIndex = indexes Vx!ZF+
I%4eX0QY=z
[indexes.length - 1];
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elseif(startIndex < 0) 1O Ft}>1
this.startIndex = 0; lz`\Q6rZ
else{ &- p(3$jn7
this.startIndex = indexes 9BakxmAc
,O:4[M !$w
[startIndex / pageSize]; !\'w>y7
} L[zTT\a
} S_sHwObFu|
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publicint getNextIndex(){ q}_8iDO6
int nextIndex = getStartIndex() + OkRb3}
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pageSize; EZWWvL
if(nextIndex >= totalCount) PlCw,=K 8f
return getStartIndex(); 2_Lu0Yrg
else Idu'+O4
return nextIndex; eV_",W
} n'ZPB
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publicint getPreviousIndex(){ i{}m 8K)
int previousIndex = getStartIndex() - 3x(Y+
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s {*rBX8N
pageSize; -n@,r%`UK
if(previousIndex < 0) t,Tq3zB
return0; =>S[Dh
else v1$}[&/
return previousIndex; &4wSX{c/P
} +sx(q@
&(<Gr0
} Mprn7=I{Tg
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抽象业务类 #F/W_G7 v
java代码: O4nA?bA
fm#7}Y
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/** "vYjL&4h
* Created on 2005-7-12 ([m4dr
*/ "'+/ax[{
package com.javaeye.common.business; A/ zAB3
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import java.io.Serializable;
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import java.util.List; VVF9X(^rQ
z>W?\[E<2
import org.hibernate.Criteria; An]Vx<PD
import org.hibernate.HibernateException; .mnkV -m
import org.hibernate.Session; ;qzn_W
import org.hibernate.criterion.DetachedCriteria; e9\_H=t+
import org.hibernate.criterion.Projections; YPs9Pqkn
import ?5G;=#I
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org.springframework.orm.hibernate3.HibernateCallback; 2UR1T~r
import UN<$F yb
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org.springframework.orm.hibernate3.support.HibernateDaoS 4[Ko|
,*[N_[
upport; ^K<!`B
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import com.javaeye.common.util.PaginationSupport; lNe5{'OrO
"Z';nmv'N
public abstract class AbstractManager extends L{ej<0 yr
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HibernateDaoSupport { s4Jy96<
W T @XHwt
privateboolean cacheQueries = false; 4U$M0 =
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privateString queryCacheRegion; \"I418T K
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publicvoid setCacheQueries(boolean ;5|d[r}k3
sCf)#6mI
cacheQueries){ ow+_g R-
this.cacheQueries = cacheQueries; &G-dxET]
} $;";i:H`
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publicvoid setQueryCacheRegion(String 'K23oQwDB
)eX{a/Be
queryCacheRegion){ xxgdp. (
this.queryCacheRegion = 5HB*
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queryCacheRegion; RdjoVCf
} ,7d#t4
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publicvoid save(finalObject entity){ `OZiN;*|
getHibernateTemplate().save(entity); 1k%HGQM{
} }_}LaEYAo
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publicvoid persist(finalObject entity){ DEPsud ;
getHibernateTemplate().save(entity); (nkiuCO
} N7q6pBA"E
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publicvoid update(finalObject entity){ qus%?B{b}
getHibernateTemplate().update(entity); ubKp
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} 'v(b^x<ZS
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publicvoid delete(finalObject entity){ :VR%I;g ;
getHibernateTemplate().delete(entity); =FAIbM>u
} Yru,YA
*aYuuRx
publicObject load(finalClass entity, 6ZXRb
a!j{A?7Kw.
finalSerializable id){ {XXnMO4uR;
return getHibernateTemplate().load ;t/KF"
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(entity, id);
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} qP9`p4c8i
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publicObject get(finalClass entity, y?iW^>|?L=
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finalSerializable id){ s?9`dv}P
return getHibernateTemplate().get /.UISArH
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(entity, id); p8iKZI]g
} 7Zft]C?|@
@6y)wA9Yx
publicList findAll(finalClass entity){ x45F-w{
return getHibernateTemplate().find("from wF-H{C'
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" + entity.getName()); "`KT7
} VTO92Eo
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publicList findByNamedQuery(finalString 0,cU^HMA
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namedQuery){ 9
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return getHibernateTemplate Ih5CtcE1'd
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().findByNamedQuery(namedQuery); 1_mqPMm
} 8%Ak
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publicList findByNamedQuery(finalString query, (Kw%fJT
cf\GC2+"^$
finalObject parameter){ -^>7\]
return getHibernateTemplate ~T=a]V
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().findByNamedQuery(query, parameter); (ul_bA+
} &!>.)I`
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publicList findByNamedQuery(finalString query, =>e>
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finalObject[] parameters){ .sZ"|j9m
return getHibernateTemplate Wm!cjGK
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().findByNamedQuery(query, parameters); IRsyy\[kp8
} cOdgBi
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publicList find(finalString query){ DH])Q5
return getHibernateTemplate().find .aC/ g?U
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(query); AD7&-=p&w
} 0>3Sn\gZ(
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publicList find(finalString query, finalObject -{p~sRc&
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parameter){ Cv<
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return getHibernateTemplate().find ^= qL[S6/M
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(query, parameter); C)&BtiUN/
} =]L ALw
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public PaginationSupport findPageByCriteria CeUC[cUQU
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(final DetachedCriteria detachedCriteria){ WFfn:WSWU
return findPageByCriteria
: !wt/Y
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); rrs0|=
} pvdCiYo1r
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public PaginationSupport findPageByCriteria /!pJ" @
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(final DetachedCriteria detachedCriteria, finalint N}'2GBqfU4
j
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startIndex){ m :2A[H+
return findPageByCriteria p|w0
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(detachedCriteria, PaginationSupport.PAGESIZE, 0>ce~KU
-]Aqt/w"l
startIndex); -T>i5'2)
} +DYsBCVbag
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public PaginationSupport findPageByCriteria T@ zV
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(final DetachedCriteria detachedCriteria, finalint $AdBX}{
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pageSize, Z)<lPg!YAR
finalint startIndex){ &[5pR60
return(PaginationSupport) ;esOe\zjE
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getHibernateTemplate().execute(new HibernateCallback(){ Lwo9s)j<e
publicObject doInHibernate YLb$/6gj6
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(Session session)throws HibernateException { +?6@%mW'
Criteria criteria = !WTL:dk
&&
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detachedCriteria.getExecutableCriteria(session); :c9 H2
int totalCount = 2k^'}7G%
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((Integer) criteria.setProjection(Projections.rowCount }qBmt>#
5I/lF oy7
()).uniqueResult()).intValue(); yVyh\u\
criteria.setProjection pL,l
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(null); 1H8/b D
List items = [=^Wj`;
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criteria.setFirstResult(startIndex).setMaxResults vU9:`@beu
_>4)q=
(pageSize).list(); U,Fyi6{~
PaginationSupport ps = ^`bMFsP
c-ql
new PaginationSupport(items, totalCount, pageSize, EvF[h:C2
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startIndex); wQ81wfr1:
return ps; No*[@D]g
} H`rd bE
}, true); (btmg<WT"
} H4<Q}([w
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public List findAllByCriteria(final `pqTiV
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DetachedCriteria detachedCriteria){ !i\ gCLg2_
return(List) getHibernateTemplate +tJ 7ZR%
WF<3
7"A@
().execute(new HibernateCallback(){ 22 feYm|
publicObject doInHibernate l_Zx'm
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(Session session)throws HibernateException { #gXxBM
Criteria criteria = iWIq~t*,H]
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detachedCriteria.getExecutableCriteria(session); 7 4]qz,
return criteria.list(); s%1ZraMvJ
} *NC@o*
}, true); -\2hSIXj
} e(Rbq8D
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public int getCountByCriteria(final @4n>I+6*&
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DetachedCriteria detachedCriteria){ Z{ 1B:aW
Integer count = (Integer) 9+3 VK
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getHibernateTemplate().execute(new HibernateCallback(){ c7RQ7\
publicObject doInHibernate iU AY
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(Session session)throws HibernateException { R[@}Lg7+v
Criteria criteria = X!m
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],Yy)<e.
detachedCriteria.getExecutableCriteria(session); /@I`V?Q!a
return 6"R'z#{OF
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criteria.setProjection(Projections.rowCount 9dWz3b1[]
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()).uniqueResult(); 9*r^1PRc
} cZ# %tT#
}, true); F6aC'<#/
return count.intValue(); KtGbpcS$f
} !;0K=~(Y^
} l2I%$|)d
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#/{3qPN?@
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Y=5P=wE
3 FV -&Y
用户在web层构造查询条件detachedCriteria,和可选的 F<XOt3VY.
QWtDZ>
startIndex,调用业务bean的相应findByCriteria方法,返回一个 (e0(GOqf4
KC)}Mzt6_
PaginationSupport的实例ps。 r-.>3J
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ps.getItems()得到已分页好的结果集 :>U+HQll
ps.getIndexes()得到分页索引的数组 5{bc&?"
ps.getTotalCount()得到总结果数 mhy='AQJ
ps.getStartIndex()当前分页索引 9zY6hh**
ps.getNextIndex()下一页索引 vrcIwCa
ps.getPreviousIndex()上一页索引 *"OUwEl a
5DVYHN9c|
b` va\'&3
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e['<.Yf+
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 is~2{:
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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 YV!hlYOBi
2;0eW&e
一下代码重构了。 N$x&k$w R
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我把原本我的做法也提供出来供大家讨论吧: Ih>s2nL
)Yv=:+f
首先,为了实现分页查询,我封装了一个Page类: |0Xf":
java代码: AI`k
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/*Created on 2005-4-14*/ P=_fYA3
package org.flyware.util.page; /KNDo^P
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/** ,Aai-AGG@
* @author Joa {M5t)-
* *} ?
*/ n,2
publicclass Page { =^i K^)
mEsb_3?#+
/** imply if the page has previous page */ D:f=Z?L)>
privateboolean hasPrePage; Od)y4nr3~
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/** imply if the page has next page */ =/`]lY&
privateboolean hasNextPage; oeB'{bG
D}LM(s3li7
/** the number of every page */ gWzslgO6
privateint everyPage; P^Owgr=Y
8-Y*b89
/** the total page number */ L!lmy&1
privateint totalPage; qz{9ND|)
gXJBb+P
/** the number of current page */ QA*<$v
privateint currentPage; e6Y>Bk
t>/x-{bH\
/** the begin index of the records by the current )*>wa%[-q
cw{TS
query */ y<E];ub
privateint beginIndex; sQac%.H;`U
#79[Qtkrhm
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/** The default constructor */ *LU/3H|}
public Page(){ q]I aRho
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} >%om[]0E
b%%r`j,'JE
/** construct the page by everyPage !Yv_V]u=
* @param everyPage UaF~[toX
* */ {MSE}|A\V
public Page(int everyPage){ 4P k%+l
this.everyPage = everyPage; XFvl
} t`+A;%=K]
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/** The whole constructor */ ]LUcOR
public Page(boolean hasPrePage, boolean hasNextPage, tVEe) QX
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$_E.D>5^%7
int everyPage, int totalPage, k#Sr; "
int currentPage, int beginIndex){ &hI!mo
this.hasPrePage = hasPrePage; IBo
this.hasNextPage = hasNextPage; <D ~hhGb
this.everyPage = everyPage; T\uIXL?3
this.totalPage = totalPage; 7I
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this.currentPage = currentPage; _huJ*W7lR
this.beginIndex = beginIndex; wW1VOj=6V"
} {zvaZY|K"
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/** R~kO5jpW
* @return Sb /?<$>
* Returns the beginIndex. Sv{n?BYq
*/ :J]'c}
publicint getBeginIndex(){ t{jY@JT|
return beginIndex; b>OB}Is
} w\o6G7
W~;Jsd=f
/** !6%?VJB|b
* @param beginIndex LSou]{R
* The beginIndex to set. <VKJ+
*/ -je} PwT
publicvoid setBeginIndex(int beginIndex){ L
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this.beginIndex = beginIndex; @6>Q&GYqt
} gGL}FNH
Ne1Oz}
/** 0BlEt1e2T
* @return f?Zjd&|Ch
* Returns the currentPage. p{^:b6
*/ 4 k<o
publicint getCurrentPage(){ @)6b
return currentPage; ^EX"fRwNi
} cZNcplt8
M/=36{,w-
/** ,r w4Lo
* @param currentPage /B@{w-N
* The currentPage to set. a31e.36g
*/ !Ud'(iGa
publicvoid setCurrentPage(int currentPage){ l5{60$g
this.currentPage = currentPage; UrizZ5a
} w5HIR/kP
m7'<k1#"Y
/** UJI2L-;Ul
* @return 6MT
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* Returns the everyPage. sX%n` L
*/ ~{/M_
=
publicint getEveryPage(){ V2Vr7v=Y"
return everyPage; f[k#Znr
} iH }-
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/** *=!e,
* @param everyPage x950,`zy
* The everyPage to set. 8~C_ng-wn
*/ UPuoIfuqI
publicvoid setEveryPage(int everyPage){ "#r)NYq`"|
this.everyPage = everyPage; }8ubGMr,Y
} 7EE{*}?0E
fZo#:"{/K
/** T?pS2I~
* @return 8Agg%*Qs}
* Returns the hasNextPage. smf"F\Ws
*/ (?r,pAc:
publicboolean getHasNextPage(){ $ZBYOA
return hasNextPage; yDafNH
} ,/{e%J
q*&R&K;q
/** -eG~
* @param hasNextPage %lHHTZ{+
* The hasNextPage to set. G tI )O}
*/ F}nwTras
publicvoid setHasNextPage(boolean hasNextPage){ 'ZuS
this.hasNextPage = hasNextPage; y!#-[K:
} rL{R=0
N y'\Q"Y]
/** XDemdMy$
* @return Z10Vx2B
* Returns the hasPrePage. k7CKl;Fck
*/ ' P?h?w^T
publicboolean getHasPrePage(){ faQmkO
return hasPrePage; !RI _Uph
} |3'
7Z< ~{eD,
/** FDz`U:8
* @param hasPrePage HT;^u"a~
* The hasPrePage to set. ]3_b3@k
*/ +X=*>^G(-
publicvoid setHasPrePage(boolean hasPrePage){ Y,}_LS$f
this.hasPrePage = hasPrePage; Jl/w P
} WoEK #,I;
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/** p~$cwbQ!
* @return Returns the totalPage. u.GnXuax
* 1r;zA<<%R
*/ *&NP?-E
publicint getTotalPage(){ w 9dkJo
return totalPage; N[e,){v
} yaj dRU
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/** BO[:=x`
* @param totalPage VzP az\e
* The totalPage to set. 3kn-tM
*/ G4)~p!TSQ
publicvoid setTotalPage(int totalPage){ 6X \g7bg
this.totalPage = totalPage; W;vNmg}mn
} tk"+ u_u w
nuce(R
} X94a
gQn%RPMh
:$WO"HfMSn
'FErk~}/4s
%fj5;}E.
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 6cH8Jr _
T`&zQQ6F'
个PageUtil,负责对Page对象进行构造: rW{!8FhI
java代码: 0pZvW
VXeO}>2S
EgjJywNhd2
/*Created on 2005-4-14*/ \2\{c1df
package org.flyware.util.page; >+2&7u
9kL,69d2
import org.apache.commons.logging.Log; bv+u7B6,
import org.apache.commons.logging.LogFactory; ){;XI2
QZzamT)"
/** _ \D%
* @author Joa w*qj0:i5as
* =XP[3~
*/ @-$8)?`q
publicclass PageUtil { x)PW4{3qR
\9?[|m
z
privatestaticfinal Log logger = LogFactory.getLog 5n@YNaoIb
8dczC
(PageUtil.class); 4>KF`?%4
WXQ@kQD
/** X6Ha C+P
* Use the origin page to create a new page 02-ql
F@i
* @param page MEDh
* @param totalRecords /F0q8j0
* @return ^ ""edCs
*/ I|@+O#
publicstatic Page createPage(Page page, int QNNURf\[(
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totalRecords){ I3t5S;_8
return createPage(page.getEveryPage(), :`bC3Mr
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page.getCurrentPage(), totalRecords); $L/`nd
} :{7+[LcH7
Xg)8}
/** KkJqqO"EL
* the basic page utils not including exception P?0X az
t<H"J__&
handler At Wv9
* @param everyPage @*6fEG{,q
* @param currentPage \x<8
* @param totalRecords g) X3:=['
* @return page /fI}QY1
*/ 1dH|/9
publicstatic Page createPage(int everyPage, int ^? fOccfQ{
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currentPage, int totalRecords){ (@?mm
everyPage = getEveryPage(everyPage); Rlq7.2cP
currentPage = getCurrentPage(currentPage); |L2>|4
int beginIndex = getBeginIndex(everyPage, SQodk:1)
384n1?
currentPage); DH(<{ #u
int totalPage = getTotalPage(everyPage, FQZ*i\G>>
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totalRecords); f{sT*_at
boolean hasNextPage = hasNextPage(currentPage, 2b"*~O;
qE)FQeN
totalPage); E7 Cobpm
boolean hasPrePage = hasPrePage(currentPage); 8U{D)KgS
5zl+M`
returnnew Page(hasPrePage, hasNextPage, ;4F6
$T'I
everyPage, totalPage, R/hf"E1
currentPage, r4yz{^G
eM7@!CdA9q
beginIndex); f|d~=\0y
} \""^'pP@
;: ;E|{e
privatestaticint getEveryPage(int everyPage){ UK =ELvt]
return everyPage == 0 ? 10 : everyPage; ,.,8-In^
} iJs~NLCgVu
{:X'9NEE
privatestaticint getCurrentPage(int currentPage){ vX+oZj
return currentPage == 0 ? 1 : currentPage; DX_mrG
} JF=R$! 5
[|]J8o@u^
privatestaticint getBeginIndex(int everyPage, int {[y6qQm
5!c/J:z
currentPage){ v">?`8V
return(currentPage - 1) * everyPage; 1T^WMn:U
} -U|c~Cqc
-]N2V'QB
privatestaticint getTotalPage(int everyPage, int %>|FJ
6= ?0&Bx&
totalRecords){ ;_}pIO
int totalPage = 0; 2#wnJdr6E
bWe2z~dP
if(totalRecords % everyPage == 0) w\buQ6pR)
totalPage = totalRecords / everyPage; (.J/Ql0Y
else V DFgu
totalPage = totalRecords / everyPage + 1 ; ^C>kmo3J
!:(+#
return totalPage; qGinlE&\
} ~D52b1f
P\U<,f
privatestaticboolean hasPrePage(int currentPage){ DE(XSzX
return currentPage == 1 ? false : true; ]*0zir/
} [|nK5(e9
E7uIur=g!
privatestaticboolean hasNextPage(int currentPage, ]c(FgYc
+R'8$
int totalPage){ +=tdgw/
return currentPage == totalPage || totalPage == Wf~^,]9N
w-|Rb~XT
h
0 ? false : true;
@|gG3
} UHl3/m7g
!0{SVsc)
]kj^T?&n.
} {*xE+ |
4^7 v@3
o}N@Q-i gq
j=sfE qN).
TKZtoQP%
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。 TOG:`FID
7[ ovEE54
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 +gl\l?>sr
k!c7eP"%8^
做法如下: ~&?([}A
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 O& Y;/$w
WK%cbFq(
的信息,和一个结果集List: XYcZ;Z 9:
java代码: I9?\Jbqg
g]~vZj
v({O*OR
/*Created on 2005-6-13*/ @-@Coy 4Tt
package com.adt.bo; !6/UwPs
{vu\qXmMv
import java.util.List; @@Ib^sB%
?9 huuJs7
import org.flyware.util.page.Page; AR |4^
91R#/i
/** h.<f%&)F
* @author Joa d`sZ"8}j
*/ vC]X>P5 Px
publicclass Result { "Q: Gd6?h;
x^s,<G
private Page page; f;E#CjlTL
+d,
~h_7!
private List content;
,,H5zmgA
VDxm|7
/** k1Y\g'1
* The default constructor Ez1eGPVr
*/ 9<mMU:
public Result(){ Wn<?_}sa|z
super(); A7 RI&g
v5
} *HrEh;3^J
_c>iux;
/** BM :x`JY
* The constructor using fields b(K"CL\p
* /k.0gYD
* @param page E'6>3n
* @param content \h
~_<)
*/ #*(}%!rD*
public Result(Page page, List content){ ;4O[/;i
this.page = page; OVLVsNg
this.content = content; r S@/@jKZE
} [6VB&
Z`TfS+O6
/** 7?dWAUF
* @return Returns the content. O-,
"/Z
*/ b++r#Q
g
publicList getContent(){ ,_V V;P
return content; BJ
UG<k
} 0["93n}r
9#DXA}
/** %A zy#m
* @return Returns the page. Ip8ml0oG
*/ Nd0tR3gi7
public Page getPage(){ +C%6jGGh
return page; &bTCTDZh
} n Bm ]?
[F<E0rjwM
/** (]@S<0
* @param content *7Vb([x4;
* The content to set. BA\aVhmx
*/ eRUdPPq_d
public void setContent(List content){ <Jgcj4D
this.content = content; YZ~MByu
} 6A"$9sj6
oU=vl!\J
/** Y"FV#<9@7E
* @param page /pMOinuO
* The page to set. 66val"^W
*/ 1EU4/6!C
publicvoid setPage(Page page){ < $zJi V
this.page = page; 'lIs`Zc5N
} ysnW3q!@
} '/O:@P5qY
MCN>3/81
']k<'`b|
FJvY`zqB
HXq']+iC
2. 编写业务逻辑接口,并实现它(UserManager, JM7mQ'`Ud
?L<B]!9HZt
UserManagerImpl) ~& -h5=3
java代码: [t4v/vQT
sVyV|!K
r;Sk[Y5#
/*Created on 2005-7-15*/ u=:f%l
package com.adt.service; /+*"*Br/
+bumWOQ'
import net.sf.hibernate.HibernateException; }40T'y
TOwqr T/
import org.flyware.util.page.Page; w)dnmrKDZg
2yA)SGri
import com.adt.bo.Result; U[wx){[|
bq/Aopfr
/** 9c^ ,v_W@
* @author Joa ~0MpB~ {xd
*/ =E9\fRGU
publicinterface UserManager { YTTyMn
Tpl]\L1v-
public Result listUser(Page page)throws
0pE>O7
D:T]$<=9
HibernateException; i{^T;uAE
wOAR NrPx2
} QFP9"FM5F
^xe+(83S2?
Y4k2=w:D
lDL&":t
`2Pa{g-.
java代码: BqNsW
(+
6ll!7U(9(
VWft/2p~
/*Created on 2005-7-15*/ 5/"$_7"{a
package com.adt.service.impl; (p>|e\(]0
R XCn;nM4
import java.util.List; Znb={hh
C]!2
import net.sf.hibernate.HibernateException; >jt2vU@t.
SwOW%o
import org.flyware.util.page.Page; x;~:p;]J2F
import org.flyware.util.page.PageUtil; UWT%0t_T
o]1BWwtY&
import com.adt.bo.Result; a7g;8t-&
import com.adt.dao.UserDAO; $INB_/RE
import com.adt.exception.ObjectNotFoundException; 9nR\7!_
import com.adt.service.UserManager; .!3e$mhV
zsp%Cz7T
/** %7ngAIg
* @author Joa hTDK[4e
*/ Qu|CXUk
publicclass UserManagerImpl implements UserManager { =F+v+zP7P
v~mVf.j1
private UserDAO userDAO; ?+]=|hN
ZDW9H6ux
/** i<Z%
* @param userDAO The userDAO to set. ?Bf>G]zx
*/ Yc[umn^K
publicvoid setUserDAO(UserDAO userDAO){ `w!XO$"]Z
this.userDAO = userDAO; c5ij2X|I
} Y5aG^wE[:
JI>Y?1i0O
/* (non-Javadoc) $cSUB
* @see com.adt.service.UserManager#listUser }a;xs};X;
R1zt6oY
(org.flyware.util.page.Page) #Y=^4 U`
*/ Mq\=pxC@
public Result listUser(Page page)throws hhU_kI
D7hTn@I
HibernateException, ObjectNotFoundException { .~i|kc]Ue
int totalRecords = userDAO.getUserCount(); Go%Z^pF3CO
if(totalRecords == 0) VM$n|[C~
throw new ObjectNotFoundException $yx\2
6ld4'oM
("userNotExist"); ">[#Ops-;$
page = PageUtil.createPage(page, totalRecords); *D|a`R!Y
List users = userDAO.getUserByPage(page); WZ' Z"'
returnnew Result(page, users); 1Dr&BXvf]8
} 7( 84j5zb
W\l&wR
} <{#_;7h"
h4]^~stI
iwF_'I$#N
A4"TJZBg}
Sp\TaUzg
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 W9?*
~!
AX`Tku
询,接下来编写UserDAO的代码: #QwkRzVoy
3. UserDAO 和 UserDAOImpl: %5e|
java代码: c!\Gj|
*^-AOSVt,
a&'9[9E1
/*Created on 2005-7-15*/ c,@Vz
7c
package com.adt.dao; ]^ R':YE
g}W`LIasv
import java.util.List; w;,34qbf
T?RY~GA
import org.flyware.util.page.Page; m}l);P^
V#Wy`
ce
import net.sf.hibernate.HibernateException; VukbvBWPN
f\
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/** AMyg>n!
* @author Joa /"e@rnn
*/ %6[,a
publicinterface UserDAO extends BaseDAO { E^)FnXe5
9Jwd *gevV
publicList getUserByName(String name)throws vbmt0df
&. =8Q?
HibernateException; >
'R{,1# U
7n5gXiI"
publicint getUserCount()throws HibernateException; "}3sL#|z
PSJj$bt;<+
publicList getUserByPage(Page page)throws &@6xu{o
Ll
KO(Q{"
HibernateException; <N)!s&D
vm! y2
} JRB6T _U
]$g07 7o
v-#,@&Uwq
)+L|<6J XA
Gsh9D
java代码: obvE m[x!Z
+<Gp >c
MnD}i&k[
/*Created on 2005-7-15*/ <{W{
Y\_A>
package com.adt.dao.impl; $z_yx
`5
:aOR@])>o
import java.util.List; no+m.B
|Z>-<]p9g
import org.flyware.util.page.Page; i"V.$|,
)5@P|{FF
import net.sf.hibernate.HibernateException; ykC3Z<pI.
import net.sf.hibernate.Query; E+Bc>xl@m
{z>!Fw
import com.adt.dao.UserDAO; $6n
J+
wNUT0 +
/** _WNbuk0
* @author Joa S]@;`_?m{
*/ 8oE`>Y
public class UserDAOImpl extends BaseDAOHibernateImpl J!om"h
sV#%U%un
implements UserDAO { ~Z5AIm R|
u4hn9**a1
/* (non-Javadoc) o%'1=d3R1Q
* @see com.adt.dao.UserDAO#getUserByName YXp\C"~g
vN(~}gOd\
(java.lang.String) G/JGb2I/7|
*/ vEfj3+e
publicList getUserByName(String name)throws 7> f2P!:
Milp"L?B%
HibernateException { ~B[e*|d
String querySentence = "FROM user in class 6c!F%xU}
#H7
SLQr\
com.adt.po.User WHERE user.name=:name"; mP*$wE9b,:
Query query = getSession().createQuery y`j_]qvt
|-ZML~2S=h
(querySentence); vP,pK=5
query.setParameter("name", name); Zd-qBOB2L
return query.list(); 6
5zx<
} hr]+4!/
Vja 4WK*
/* (non-Javadoc) waMV6w)<
* @see com.adt.dao.UserDAO#getUserCount() (EcP'F*;;y
*/ pT=^o
publicint getUserCount()throws HibernateException { [.>=>KJ_
int count = 0; 79 4UY
String querySentence = "SELECT count(*) FROM 'TYO-'aC
N&G'i.w/
user in class com.adt.po.User"; D zD5n
Query query = getSession().createQuery .iV=ybMT
<h#7;o
(querySentence); o1#3A
count = ((Integer)query.iterate().next #)}BY"C%
C] Fw*t
()).intValue(); V(Pw|u"
e
return count; +7%?p"gEY\
} 7l7VT?<:
&/[MWQ
/* (non-Javadoc) T"P}` mT
* @see com.adt.dao.UserDAO#getUserByPage ~U w<e~
oQ,n?on
(org.flyware.util.page.Page) ]0'cdC
*/ r??_2>Q
publicList getUserByPage(Page page)throws E"*E[>
D`QMlRzXy
HibernateException { _b8KK4UR
String querySentence = "FROM user in class 9U;
Yp(0 XP5o
com.adt.po.User"; <U$YJtEK
Query query = getSession().createQuery :JSxsA6k
7[=G;2<
(querySentence); 274j7Y'
query.setFirstResult(page.getBeginIndex()) 9+y&&;p
.setMaxResults(page.getEveryPage()); ~ ?nn(Q-
return query.list(); lO\HchGzB
} ]+`K\G ^X
TNh&g.
} V^tD@N
|};d:LwX
#qVvh3#g
w &YUb,{Y
?J6Ek*E#
至此,一个完整的分页程序完成。前台的只需要调用 #NyO'
)7Hx<?P
userManager.listUser(page)即可得到一个Page对象和结果集对象 RNB-W%
bCP2_h3*
的综合体,而传入的参数page对象则可以由前台传入,如果用 "{@[06|1
{
(.@bT@
webwork,甚至可以直接在配置文件中指定。 >]_6|Wfl
W2h*t"5W
下面给出一个webwork调用示例: 78]*Jx>L
java代码: a9&[Qv5-/
\roJf&O }
|}^u<S8X
/*Created on 2005-6-17*/ W0x9^'=s\
package com.adt.action.user; v8)wu=u
Ib{#dhV
import java.util.List; 7>im2"zm
%_n%-Qn
import org.apache.commons.logging.Log; ?`OFn F,K
import org.apache.commons.logging.LogFactory; (ID%U
import org.flyware.util.page.Page; w)J-e gc
5.-:)=
import com.adt.bo.Result; r=.@APZB
import com.adt.service.UserService; G "+[@|
import com.opensymphony.xwork.Action; f\?Rhyz
1d!s8um;
/** FLJ&ZU=s
* @author Joa ~c&sr5E
*/ |5>A^a
publicclass ListUser implementsAction{ O*+HK1q7
A%EhRAy
privatestaticfinal Log logger = LogFactory.getLog 5G6 P p7[
N/lEfy<&g:
(ListUser.class); QpzdlB44l
OS%[SHs
private UserService userService; 5fs,UH
k2loGvBJ
private Page page; F+VNrt-
DNDzK
iMk
privateList users; C!547(l[
Uth+4Aq
/* $C=XSuPNK
* (non-Javadoc) c{`!$Z'k<
* ((AK7hb
* @see com.opensymphony.xwork.Action#execute() mGg/F&G9
*/ 4D5Wse
publicString execute()throwsException{ ~Ih`
ayVq
Result result = userService.listUser(page); e4_A`j'
page = result.getPage(); IW@xT@
users = result.getContent(); *:\[;69[
return SUCCESS; vS ( Y_6
} P$Yw'3v/
x]Nx,tt
/** HQF@@
* @return Returns the page. fb0)("_V
*/ <Ed; tq
public Page getPage(){ f@9XSZ<.71
return page; zGme}z;1@
} KN@ [hb7%
r25VcY
/** !iHC++D
* @return Returns the users. |0p@'X1
*/ e|SNb*_
publicList getUsers(){ o=7e8l
return users; .|DrXJ\c
} ~U7Bo(EJp
3J8>r|u;1'
/** ADxje%!1O
* @param page 08AD~^^
* The page to set. 2xi;13?
*/ 82)=#ye_P
publicvoid setPage(Page page){ X ?ZLmP7|
this.page = page; 4uE)*1
} {]|<|vc;GI
V]]!0ugvk(
/** O.Te"=^"F
* @param users 19% "F!^i
* The users to set. r4K_Wp
*/ @D["#pe,}
publicvoid setUsers(List users){ EAr;
this.users = users; ?|oN}y"i
} ~T9QpL1OJ
q|klsup
/** kwww5p ["
* @param userService 8)s0$64Ra
* The userService to set. TWRnty-C
*/ Wd+kjI \
publicvoid setUserService(UserService userService){ WAuT`^"u
this.userService = userService; c|'$3dB*
} GM8>u O
} >'m&/&h
9 M?UPE
5D-as9k*
q$H@W.f
2ZbSdaM=
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, :%28*fl
jL)Y'
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
5Uhxl^c
GaJE(N
么只需要: VqD_FS;E
java代码: f]sR4mhO
iz [IK%K
U![$7k>,pr
<?xml version="1.0"?> Dbx zqd
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork n0K+/}m
xe.f]a
1.0//EN" "http://www.opensymphony.com/xwork/xwork- 1NTx?JJfW
rHybP6C<
1.0.dtd"> l7<VH z0b
PktnjdFV
<xwork> p.MLKp-'
KqBiF]Q
<package name="user" extends="webwork- -W/D Cj<
3*{l^<`:gA
interceptors"> kE+fdr\ T
@^#
9N!Fj]
<!-- The default interceptor stack name
DHhty qm
_BgWy#
--> 9J_vvq`%`
<default-interceptor-ref ?J+*i
d
GVf[H2%H
name="myDefaultWebStack"/> s/3sOb}sA
"-5FUKI-
<action name="listUser" qauvwAMuX
lA6{TH.x
class="com.adt.action.user.ListUser"> 'UGgY3
<param P uQ
U5F1m]gFr
name="page.everyPage">10</param> 9N2.:<so
<result N!tNRMTi
yk^2<?z>2
name="success">/user/user_list.jsp</result> #K` [XA
</action> JvCy&xrE;
[H$kVQC
</package> 39~WP$GM
@C('kUX~!
</xwork> !6#.%"{-
juu"V]Q1
q{[y4c1bG{
\O~WMN
?}uvpB1}
"}[ ]R
这样就可以通过配置文件和OGNL的共同作用来对page对象设置初值 OB+ cE4$
kA2)T,s74
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。
>h9~
/
ljg6uz1v%
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 `USze0"t0:
Q2m 5&yy@s
.G<Or`K^i
l;h -`( 11
<P*7u\9&
我写的一个用于分页的类,用了泛型了,hoho tqt~F2u
Xp6Z<Z&N
java代码: wk=s3^
a_D K"8I
)1YGWr;ykS
package com.intokr.util; z,!A4ws
G!D~*B9G
import java.util.List; ]r#NjP
R&'Mze fb
/** tPw7zFy6r
* 用于分页的类<br> dJb7d`
* 可以用于传递查询的结果也可以用于传送查询的参数<br> l{kacfk#
* i4SWFa``
* @version 0.01 >RiU/L
* @author cheng ~X;sa,)L1+
*/ -l"8L;`
public class Paginator<E> { oChf&W 8u
privateint count = 0; // 总记录数 2@&"*1(Xu
privateint p = 1; // 页编号 0'zjPE#
privateint num = 20; // 每页的记录数 ~PN[ #e]
privateList<E> results = null; // 结果 idS+&:'
)Dcee@/7S
/** 5mZ9rLn
* 结果总数 CWD
$\K G
*/ sI4
FgO
publicint getCount(){ )%:
W;H
return count; G+3uY25y
} %2?"x*A
)R@Y$*fm
publicvoid setCount(int count){ )1)&fN41i#
this.count = count; f\:I1y
} Z#GR)jb+
\x_$Pu
/** 0U2dNLc
* 本结果所在的页码,从1开始 On+0@hh
* B]>rcjD
* @return Returns the pageNo. ]go.IfH
*/ nF
'U*
publicint getP(){ iZ(p]0aP7
return p; u^L_X A
} EYZ,GT-I
6fT^t!<i
/** I(9+F
* if(p<=0) p=1 ^w*vux|F
* 8nSw7:z
* @param p 2%pe.stQ
*/ `ih#>i_&
publicvoid setP(int p){ '?E@H.""
if(p <= 0) A.!3{pAb
p = 1; ?Xp+5{
this.p = p; c,*a|@
} s6oIj$
{Q0DHNP(G
/**
Bf,}mCq
* 每页记录数量 gdqED}v
*/ t.7_7`bin~
publicint getNum(){ $bk_%R}s
return num; A&Q!W)=
} Ez>!%Hpn\
sgB|2cj;j
/** u3PM 7z!~
* if(num<1) num=1 ZgzYXh2
*/ Ak\"C4s
publicvoid setNum(int num){ ZB,UQ~!Yr
if(num < 1) KeC&a=HL
num = 1; ;FjI!V
this.num = num; {5T:7*J
} w6l56CB`
vXR27
/** `u8=~]rblj
* 获得总页数 x=1Sbs w{
*/ pzDz@lAwR
publicint getPageNum(){ V##T G0
return(count - 1) / num + 1; O$Dj_R#
} J]&nZud`
2u}ns8wn
/** ^coj ETOv
* 获得本页的开始编号,为 (p-1)*num+1 7"{CBbT
*/ S`[r]msw
publicint getStart(){ []H0{a2{<
return(p - 1) * num + 1; z|N*Gs>,
} CDFkH
;BEX|wxn
/** CWE^:kr6
* @return Returns the results. 0h"uJco,
*/ ${7s"IX
publicList<E> getResults(){ ">R`S<W
return results; ]=%u\~AvL
} Lor__
K
jx];=IC3tt
public void setResults(List<E> results){ %U&ztvR0C
this.results = results; StMvz~
} )B Xl|V,
5R#:ALwX:
public String toString(){ Q".p5(<
StringBuilder buff = new StringBuilder lp]q%P
dcN4N5r
(); R!_1 *H$
buff.append("{"); 7FP
@ v ng
buff.append("count:").append(count); +|spC
buff.append(",p:").append(p); ; 5!8LmZ0#
buff.append(",nump:").append(num); FVoKNaK-
buff.append(",results:").append +hMF\@
NJ!}(=1|K
(results); D+Z,;XZ
buff.append("}"); Um
I,?p
return buff.toString(); M_F4I$V4
} H~ =;yy
4' <y
} }+
TA+;
uulzJbV,K
O>arCr=H