Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 B<99-7x3
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 (R.l{(A
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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 |XDbf3^6
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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 G`/5=
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。 F9Hxqa#1T
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分页支持类: >@g+%K]
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java代码: ~`xaBz0q
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package com.javaeye.common.util; ~t>i+{JKE
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import java.util.List; IL]Js W
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publicclass PaginationSupport { lU`}
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publicfinalstaticint PAGESIZE = 30; ^&!SnM
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privateint pageSize = PAGESIZE; 4N!Eqw
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privateList items; ul-A'
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privateint totalCount; `kRv+Qwfa
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privateint[] indexes = newint[0]; B24,;2J
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privateint startIndex = 0; -p-<mC@<&S
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public PaginationSupport(List items, int <`f~Z|/-_(
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totalCount){ ru#CywK{{;
setPageSize(PAGESIZE); IyV%tOy
setTotalCount(totalCount); q-3e^-S*
setItems(items); 2Hp<(
setStartIndex(0); G@N-+
} aANzL
mdB~~j
public PaginationSupport(List items, int KE_GC ;bQ
0ECQ>Ux:
totalCount, int startIndex){ C)RJjaOr
setPageSize(PAGESIZE); ng-rvr
setTotalCount(totalCount); U9/>}Ni%3G
setItems(items); 4#fgUlV
setStartIndex(startIndex); !</Snsi
} gz~)v\5D/
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public PaginationSupport(List items, int ?j:g. a+U
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totalCount, int pageSize, int startIndex){ fJdTVs@
setPageSize(pageSize); BMJsR0
setTotalCount(totalCount); HC$rC"f
setItems(items); =9;2(<A
setStartIndex(startIndex); <0M2qt8
} B']}n`g
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publicList getItems(){ {I9<W'k{
return items; p4sU:
} g4U`Qf3
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publicvoid setItems(List items){ b&_u+g
this.items = items; 7W7yjG3g
} d+iV19 #i
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publicint getPageSize(){ c)q'" r
return pageSize; c_Fz?R+f?K
} 1<n'F
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publicvoid setPageSize(int pageSize){ tsys</E&
this.pageSize = pageSize; L_(Y[!
} 6EY W:o
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publicint getTotalCount(){ 9_&N0>OF
return totalCount; Y3M"a8 e'
} L8.u7(-#
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publicvoid setTotalCount(int totalCount){ $>6Kn`UX
if(totalCount > 0){ )ipTm{
this.totalCount = totalCount; G$7!/O%#_
int count = totalCount / !IAd.<,
o7^u@*"F
pageSize; dkI(&/
if(totalCount % pageSize > 0) rpn&.#KS
count++; 7Pp~)Kq=
indexes = newint[count]; 9zac[tno
for(int i = 0; i < count; i++){ 'j oE-{
indexes = pageSize * {Ip)%uR
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i; Ew$-,KC[
} =CGB}qU l0
}else{ v#E RXIrf
this.totalCount = 0; 1 ,e`,
} LvbS")
} /}&@1
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publicint[] getIndexes(){ jB -wJNP/
return indexes; z>9gt
} -$@4e|e%a
!^_G~`r$2J
publicvoid setIndexes(int[] indexes){ z3|)WS^
this.indexes = indexes; ?CHFy2%Y
} u.R
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publicint getStartIndex(){ O9jpt>:kZ
return startIndex; kp>AZVk
} n^:Wc[[m
S1G=hgF_L
publicvoid setStartIndex(int startIndex){ 3oE3bBj
if(totalCount <= 0) e,rCutA)
this.startIndex = 0; M%@=BT
elseif(startIndex >= totalCount) w?Nx^)xX
this.startIndex = indexes <lFQ4<"m
+~cW0z
[indexes.length - 1]; /Q*cyLv
elseif(startIndex < 0) ;VIW/
this.startIndex = 0; ]CZ&JL
else{ _?J:Z*z?
this.startIndex = indexes GFmVR2z_+
n3LCQ:]Tf
[startIndex / pageSize]; .>bvI1
} E])X$:P?
} -Yf pfNt
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publicint getNextIndex(){ q[T='!Z\
int nextIndex = getStartIndex() + Bp:i[9w
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pageSize; b*@y/ e\u`
if(nextIndex >= totalCount) 6D n[9V
return getStartIndex(); i[x;k;m2q
else {S;/+X,
return nextIndex; +w'{I`QIL0
} JJe?Zu\
n^m6m%J)
publicint getPreviousIndex(){ ]/C1pG*o
int previousIndex = getStartIndex() - Mk"V%)1k
<D!\"C
pageSize; ?]bZ6|;2
if(previousIndex < 0) #H1ng<QV
return0; (HZzA7eph
else j)[
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return previousIndex; ?[K\X
} beM}({:`
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} !ENb \'>J>
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抽象业务类 P{!r<N
java代码: !SFF 79$c
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/** Kpo{:a
* Created on 2005-7-12 =Qcz :ng
*/ 9V%s1@K
package com.javaeye.common.business; }FTyRHD|
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import java.io.Serializable; K8l|qe
import java.util.List; ,\FJVS;NeJ
=N9a!ii|
import org.hibernate.Criteria;
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import org.hibernate.HibernateException; HZ1e~IIw
import org.hibernate.Session; 54 Baz
import org.hibernate.criterion.DetachedCriteria; 1o;+.]B
import org.hibernate.criterion.Projections; d2x|PpmH
import _:,:U[@Vz
T{iv4`'
org.springframework.orm.hibernate3.HibernateCallback; /Wh}
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import ,4-) e
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org.springframework.orm.hibernate3.support.HibernateDaoS SY`
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z~/z>_y$nv
upport; R^.oM1qu|
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import com.javaeye.common.util.PaginationSupport; pN)9GO5
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public abstract class AbstractManager extends &sp7YkaW
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HibernateDaoSupport { dooS|Mq
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privateboolean cacheQueries = false; 99@uU[&IJ
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privateString queryCacheRegion; $#g1Mx{
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publicvoid setCacheQueries(boolean X=Q)R1~6v
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cacheQueries){ {q%wr*
this.cacheQueries = cacheQueries; :h
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} }@Ij}Ab>
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publicvoid setQueryCacheRegion(String G}d-L!YbE'
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queryCacheRegion){ C:/O]slH
this.queryCacheRegion = ,~-"EQT
]A:n]mL
queryCacheRegion; F$UvYy4O d
} )\C:|
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publicvoid save(finalObject entity){ (PjC]`FK
getHibernateTemplate().save(entity); M-3kF"
} c
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publicvoid persist(finalObject entity){ `Ym7XF&
getHibernateTemplate().save(entity); kh/n|2
} .7Zb,r
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publicvoid update(finalObject entity){ {
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getHibernateTemplate().update(entity); e`%U}_[d
} -t_t3aU|
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publicvoid delete(finalObject entity){ _5(lp} s
getHibernateTemplate().delete(entity); w yP|#Z\
} V&U1WV/
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publicObject load(finalClass entity, fr$E'+l)
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finalSerializable id){ fmf3Hp@
return getHibernateTemplate().load 5qzFH,
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(entity, id); {3F;:%$`c
} pj:s+7"t
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publicObject get(finalClass entity, q(sEN!^L`
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finalSerializable id){ T8( \:v
return getHibernateTemplate().get Atc<xp
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(entity, id); "]\sw"zO?
} od=%8z
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publicList findAll(finalClass entity){ 22aS
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return getHibernateTemplate().find("from ru#,pJ=O(
$VOSd<87
" + entity.getName()); .)L%ANf
} .J0s_[
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publicList findByNamedQuery(finalString 1h uU7xuf
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namedQuery){ ]
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return getHibernateTemplate DX>Yf}
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().findByNamedQuery(namedQuery); 1t&LNIc|^
} Jg} w{,
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publicList findByNamedQuery(finalString query, /Kcp9Qx
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finalObject parameter){ X{cFqW7
return getHibernateTemplate $gZC"~BR
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().findByNamedQuery(query, parameter); Z:>)5Z{'
} t&5N{C:
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publicList findByNamedQuery(finalString query, z~8`xn,
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finalObject[] parameters){ P){b"`f
return getHibernateTemplate `"@Pr,L
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().findByNamedQuery(query, parameters); p>Z18
} Xy(8}
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publicList find(finalString query){ 0iS"V^aH
return getHibernateTemplate().find }4$k-,1S
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(query); dgbqMu"
} dWKjVf
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publicList find(finalString query, finalObject 2TQyQ%
2!@ER i
parameter){ LIah'6qR
return getHibernateTemplate().find Qqm$Jl!
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(query, parameter); vZ6_/ew8
} !+R_Z#gB
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public PaginationSupport findPageByCriteria 9nGS"E l{
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(final DetachedCriteria detachedCriteria){ -F->l5
return findPageByCriteria :`Sd5b>
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); yb/v?q?Fk
} wC&+nS1
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public PaginationSupport findPageByCriteria vx7wW<e%D
PR+L6DT_
(final DetachedCriteria detachedCriteria, finalint oS0rP'V^
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startIndex){ o],z/MPL
return findPageByCriteria f.e4 C,
x<=<Lx0B;
(detachedCriteria, PaginationSupport.PAGESIZE, QKP@+E_U
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startIndex); m[w 8|[
} &sA@!
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public PaginationSupport findPageByCriteria ZHN}:W/p
x2M{=MExE.
(final DetachedCriteria detachedCriteria, finalint >|W\8dTQ
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pageSize, +)<H,?/
finalint startIndex){ IpYw<2'
return(PaginationSupport) lm[LDtc
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getHibernateTemplate().execute(new HibernateCallback(){ 4xsnN@b
publicObject doInHibernate n38l!m(.
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#
(Session session)throws HibernateException { ^`f( Pg!
Criteria criteria = O_^X:0}
-;s-*$I
detachedCriteria.getExecutableCriteria(session); r>kDRIHB
int totalCount = {)y8Y9G
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((Integer) criteria.setProjection(Projections.rowCount O{&wqV5m"
@7z_f!'u
()).uniqueResult()).intValue(); !fT3mI6u\
criteria.setProjection *{%d{x}l
r$/.x6g//
(null);
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List items = *<IQ+oat,a
X)^&5;\`
criteria.setFirstResult(startIndex).setMaxResults iTpK:pX
V+dFL9
(pageSize).list(); R)u ${
PaginationSupport ps = c
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6JZ$;x{j
new PaginationSupport(items, totalCount, pageSize, $ 8WJ$73
h_?#.z0ih;
startIndex); >^V3Z{;
return ps; o<f|jGY0
} ;=oGg%@aP
}, true); cd?a rIV5
} K26x,m]p
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public List findAllByCriteria(final vo3[)BDbT
p}{V%!`_
DetachedCriteria detachedCriteria){ OK1f Y`$z
return(List) getHibernateTemplate DUOSL
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().execute(new HibernateCallback(){ Kj`sq":Je0
publicObject doInHibernate V9r58hbVT
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(Session session)throws HibernateException { MI<XLn!*
Criteria criteria = VN[i;4o:|
Vo-]&u&cr
detachedCriteria.getExecutableCriteria(session); ;rJ
return criteria.list(); DfL>fk
} q=|0lZ$`V_
}, true); dtT2h>h9
} c-, 6k
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public int getCountByCriteria(final t1h2ibO
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DetachedCriteria detachedCriteria){ -a(\(^NW
Integer count = (Integer) QW_QizR>|
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getHibernateTemplate().execute(new HibernateCallback(){ -$J%.fdPs
publicObject doInHibernate U~Ai'1?xz
gc6T`O-_;
(Session session)throws HibernateException { 7L=V{,,v
Criteria criteria = }:5>1FfX=
1 n86Mp1.e
detachedCriteria.getExecutableCriteria(session); uVBMI.&w
return ~"ij,Op,3
>&kb|)
criteria.setProjection(Projections.rowCount
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-S(_ZbeN
()).uniqueResult(); jt/
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} _Di}={1[.
}, true); BkTGH.4G%
return count.intValue(); fP9k(mQX
} fDa$TbhjI
} .C2.j[>
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7
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用户在web层构造查询条件detachedCriteria,和可选的 XU}sbbwu
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 Je6=N3)
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PaginationSupport的实例ps。 r|WoM39bp
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ps.getItems()得到已分页好的结果集 M zLx2?
ps.getIndexes()得到分页索引的数组 82X}@5o2
ps.getTotalCount()得到总结果数 "lp),
ps.getStartIndex()当前分页索引 fi[c^e+IX
ps.getNextIndex()下一页索引 O_p:`h:;M
ps.getPreviousIndex()上一页索引 E!4Qc+.
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 hr<E%J1k%
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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 %KeQp W
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一下代码重构了。 $FgpFxz;
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我把原本我的做法也提供出来供大家讨论吧: H>-?/H
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首先,为了实现分页查询,我封装了一个Page类: :zC'jceO
java代码: m<BL/7
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/*Created on 2005-4-14*/ c?0uv2*Yh
package org.flyware.util.page; 3986;>v
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/** #EpDIL
* @author Joa N
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* (WK$
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*/ [UI4YZu}
publicclass Page { =*q:R9V
eB:obz
/** imply if the page has previous page */ -K`0`n}
privateboolean hasPrePage; qVFz-!6b
|67j__XC
/** imply if the page has next page */ U/M(4H3>H
privateboolean hasNextPage; x7J|
rbnu:+!
/** the number of every page */ s
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privateint everyPage; zjh&?G]:G
fV3!x,H
/** the total page number */ S\Qh#yFT
privateint totalPage; 0>-l {4srs
2I:vie
/** the number of current page */
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privateint currentPage; Kg>+5~+E?q
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/** the begin index of the records by the current _Bh-*l?K>
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query */ piO+K!C0n:
privateint beginIndex; Ifu$p]~z$
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/** The default constructor */ J1"u,H F*(
public Page(){ "2CiW6X[M
?|+bM`
} CScM;U=
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/** construct the page by everyPage )%C482GO-
* @param everyPage pi5Al)0
* */ SGH"m/ e
public Page(int everyPage){ IgC)YIhd
this.everyPage = everyPage; 4(&00#Yxg2
} =[`wyQe`_
U;KHF{Vm
/** The whole constructor */ j2#Vdw|j
public Page(boolean hasPrePage, boolean hasNextPage, qo.~5
bE^Z;q19
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int everyPage, int totalPage, y]?%2ud/ =
int currentPage, int beginIndex){ 9L?EhDcDV
this.hasPrePage = hasPrePage; <l5{!g
this.hasNextPage = hasNextPage; &P!^k0NJR
this.everyPage = everyPage; ]xf{.z
this.totalPage = totalPage; oCSf$g8q
this.currentPage = currentPage; tF&%7(EU3
this.beginIndex = beginIndex; (EUX>IJ
} sb(,w
"
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/** I~"-
* @return e\.|d<N?
* Returns the beginIndex. . xX xjl
*/ ,y2ur 2
publicint getBeginIndex(){ xVKx#X9yk
return beginIndex; )TyL3Z\>(
} D2>EG~xWq
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/** "=|yM~V
* @param beginIndex Ff& VBm
* The beginIndex to set. LjXtOF
*/ *kL1r
w6
publicvoid setBeginIndex(int beginIndex){ 5.VA1
this.beginIndex = beginIndex; 7=T0Sa*;
} 1y_{#,{>
ET_}x7
/** >g93Bj*
* @return )J (ekfM
* Returns the currentPage. Aid{PGDk
*/ $F G4wA
publicint getCurrentPage(){ &.<{c
`-
return currentPage; :!tQqy2
} 5qG7LO.
X/i8$yqv
/** zK:/
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* @param currentPage
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* The currentPage to set. gNLjk4H,S[
*/ X^9_'T9
publicvoid setCurrentPage(int currentPage){ # JuO
this.currentPage = currentPage; N4fuV?E`
} 3QUe:8
D9H|]W ~
/** <ze'o.c
* @return C)#:zv m
* Returns the everyPage. `?=AgGg
*/ qg.[M*
publicint getEveryPage(){ ! h&hPY1
return everyPage; uaJ5'*
} A7|"0*62
pb E`Eq
/** S*#y7YKI
* @param everyPage 30<dEoF
* The everyPage to set. yo
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*/ |[o2S9 0
publicvoid setEveryPage(int everyPage){ r*+9<8-ZX<
this.everyPage = everyPage; &% M^:WT
} 0U`Ic_.
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/** :?RK>}4|F
* @return S~Q7>oNm
* Returns the hasNextPage. tinN$o
Xy
*/ =/dW5qy;*+
publicboolean getHasNextPage(){ sSD(mO<(
return hasNextPage; IUc!nxF#
} 3\mFK$#sr
M"p $9t
/** G =< KAJ
* @param hasNextPage SC|cCK hqi
* The hasNextPage to set. M9f*7{c
*/ u%}vTCg*p
publicvoid setHasNextPage(boolean hasNextPage){ )[nzmL*w
this.hasNextPage = hasNextPage; t'9E~_!C
} IyP\7WZ
Ujj2A^
/** tanuP@O
* @return y[r T5ed
* Returns the hasPrePage. 9=<
Z>
*/ z9dVT'
publicboolean getHasPrePage(){ E>'pMw
return hasPrePage; NoYu"57\
} zo\XuoZ
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/** oY.JK
* @param hasPrePage aL=VNZ!Pqc
* The hasPrePage to set. &G<ZK9Ot}0
*/ jsez$m%vs
publicvoid setHasPrePage(boolean hasPrePage){ l0Pg`wH,
this.hasPrePage = hasPrePage; u:,B"!
} 0|GxOzNd
uN`ACc)ESi
/** *VRFs=
* @return Returns the totalPage. X^xu$d6
* 4El{2cfA
*/ Q?1 KxD!
publicint getTotalPage(){ O]2h=M@q.
return totalPage; 7B&nV92S
} ( I,V+v+{Y
;H\,w/E9
/** 4G`YZZQ
* @param totalPage B:x4H}`vh
* The totalPage to set. zcZr
)Oh
*/ ]e"NJkcm
publicvoid setTotalPage(int totalPage){ /+IR^WG#C}
this.totalPage = totalPage; n$=n:$`q
} BC4u,4S
a[#4Oq/t$
} f%@Y
XGf
t"BpaA^gO
Hss{Sb(
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np>*O }r*
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 jgGn"}
2G'G45Q
个PageUtil,负责对Page对象进行构造: +>:X4A*
java代码: ;\&7smE[
7rr5$,Mv
ZjI^0D8
/*Created on 2005-4-14*/ <XLATS8Y
package org.flyware.util.page; |Xu7cCh$me
UNhD
import org.apache.commons.logging.Log; T:}Ed_m}q
import org.apache.commons.logging.LogFactory; 1MV^~I8Dd
F%Mlid;1
/** 9X*q^u
* @author Joa ix$+NM<n
* Jp,ohVRNq
*/ Nm^q.)dO
publicclass PageUtil { {_
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sY#K=5R
privatestaticfinal Log logger = LogFactory.getLog hnY^Z_v!
(8EZ,V:
(PageUtil.class); q&W#nWBV
H+: $ 7;
/** twN(]w}Ps|
* Use the origin page to create a new page hi
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* @param page MBwp{ET!p
* @param totalRecords Fvv6<E
* @return XSD7~X/:
*/ Xg%zE
publicstatic Page createPage(Page page, int 2]C0d8=*?
-pjL7/ gx
totalRecords){ tx.YW9xD
return createPage(page.getEveryPage(), ER|5_
*yX_dgC>[
page.getCurrentPage(), totalRecords); ?=T&|pp
} j1d=$'a "
,~kMkBkl~
/** 43VuH
* the basic page utils not including exception +V7p?iEY
LvA IAknc
handler H R
V/ A
* @param everyPage #/1Bam6
* @param currentPage DV.MvFV
* @param totalRecords
:?^(&3;
* @return page ~\kRW6
*/ 9GGBJTk-
publicstatic Page createPage(int everyPage, int
)3 v8
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currentPage, int totalRecords){ -+4$W{OK*0
everyPage = getEveryPage(everyPage); 0loC^\f
currentPage = getCurrentPage(currentPage); \m\.+q]
int beginIndex = getBeginIndex(everyPage, 1ii.nt1u
UHg^F4>4
currentPage); Ri3m438
int totalPage = getTotalPage(everyPage, Z?@07Y[|K
Q^F-8
totalRecords); ilHj%h*z
boolean hasNextPage = hasNextPage(currentPage, Ln:
y|t
Gs9jX/#
totalPage); u*U?VZ5
boolean hasPrePage = hasPrePage(currentPage); Y{S/A *X
);*GOLka
returnnew Page(hasPrePage, hasNextPage, D0-e,)G}V,
everyPage, totalPage, dy0!Zz
currentPage, 0b|!S/*A3
O4#zsr:"
beginIndex); 5QT9
} lWdE^-
tDwXb>
privatestaticint getEveryPage(int everyPage){ '-~86Q
return everyPage == 0 ? 10 : everyPage; +pV3.VMH0
} nDo|^{!L`
<0vvlOL5
privatestaticint getCurrentPage(int currentPage){ lg=[cC2
return currentPage == 0 ? 1 : currentPage; vSyN_ AB?$
} iVl"H@m/
K~E]Fkw!;
privatestaticint getBeginIndex(int everyPage, int Ue\&
2V0R|YUt
currentPage){ q\/|nZO4
return(currentPage - 1) * everyPage; 9QYU
J
} $ OR>JnV
(+U!#T]'D
privatestaticint getTotalPage(int everyPage, int I2Us!W>6-
[_~U<
totalRecords){ DUtpd|
int totalPage = 0; #}gc6T~0
mB,7YZv
if(totalRecords % everyPage == 0) X >**M
totalPage = totalRecords / everyPage; {u1t.+
else *83+!DV|
totalPage = totalRecords / everyPage + 1 ; 7+fik0F
k~gQn:.Cx
return totalPage; b6i0_fOO
} E=B9FIx~<
~9n@MPS^!
privatestaticboolean hasPrePage(int currentPage){ GphG/C (
return currentPage == 1 ? false : true; &sKYO<6K}
} '=ZE*nGC
v#X? KqD
privatestaticboolean hasNextPage(int currentPage, sM4wh_lO
9}\T?6?8pX
int totalPage){ 6lhVwgy3A
return currentPage == totalPage || totalPage == [DE8s[i-
+:t1P V;l
0 ? false : true; hb_Ia]b
} RWoiV10
Md~mI8
UxW>hbzr&V
} r`krv-,O$
{P]l{W@li
I;`V*/s8"
#"Zr#P{P
l^vq'<kI
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。 wVPq1? 9
g7H;d
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 #Q{6/{bM&J
w_-{$8|
做法如下: AV'>
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 jy*wj7fj1
Gg&jb=
的信息,和一个结果集List: RsY<j& f
java代码: '5Y8 rv<
-py.YZ
z#\Z|OKU
/*Created on 2005-6-13*/ S38D
cWIw
package com.adt.bo; + ]__zm/^
%d>Ktf
import java.util.List; "au"\}
z
XvWo6
import org.flyware.util.page.Page; h{! @^Q
"&r1&StO
/** o1Xk\R{
* @author Joa R_*\?^k|A
*/ "L,FUo^&
publicclass Result { cVz.ac
Wb|IWnH$
private Page page; YgDgd\
T#( s2
private List content; -r,J>2`l
\\'!<Bn2d
/** ^GbyA YEp
* The default constructor eL(T
*/ X23TS`
public Result(){ :?S2s Ne2
super(); 2"mO"2d%
} /0r2v/0
RFZrcM
/** Q~]R#S
* The constructor using fields \Lc
pl-;?
* 7Ua
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* @param page & .#0jb1r
* @param content a@ lK+t
*/ w3& F e=c
public Result(Page page, List content){ c_".+Fa
this.page = page; A$oYw(m#
this.content = content; +(<CE#bb[
} 9(iJ=ao (
pymT-
/** :l6sESr
* @return Returns the content. YZoudX'"
*/ sFGXW
publicList getContent(){ [A3hrSw
return content; "_(o% \"7
} kL&^/([9
v/^2K,[0>
/** y /PEm)=Tt
* @return Returns the page. n3)g{K^
*/ ~U^0z|.
public Page getPage(){ #v v
k7
return page; >N*QK6"=|
} 4];NX
h)YqC$A-s
/** q<7Nz]Td
* @param content #fFEo)YG
* The content to set. 6IvLr+I
*/ ^+P]_< 43
public void setContent(List content){ ]v lQNd?
this.content = content; 8en85
pp8P
} b'ew
Od=
J%}}(G~
/** hsl Js^
* @param page W9u(
* The page to set. #ucOjdquq
*/ SKYS6b
publicvoid setPage(Page page){ GI~;2 `V
this.page = page; 7f`jl/
} O|OPdD
} & XrV[d[>
KDY~9?}TM
#<?j784
7{b|+0W
:Z/ig%
2. 编写业务逻辑接口,并实现它(UserManager, pY:xxnE
7tyn?t0n
UserManagerImpl) MjLyB^M
java代码: ?!
kup
ly{~X
+ W +<~E
/*Created on 2005-7-15*/ Pajr`gU
package com.adt.service; A5nu`e9&
\F<]l6E
import net.sf.hibernate.HibernateException; *D\nsJ*g
|D^[]*cEH
import org.flyware.util.page.Page; UL{Xe&sT
E(S}c*05O
import com.adt.bo.Result; aEgzQono
H!xBFiOH$n
/** on(W^ocnD
* @author Joa L
~
*/ kp0>8rkF
publicinterface UserManager { eR3!P8t
0">#h
public Result listUser(Page page)throws TM"i9a? ;
MLp5Y\8*
HibernateException; CE?R/uNo{
[,fMh $t
} "PlM{ZI\
2
{31"
QGsUG_/_P
CwT52+Jb
{UwJg
java代码: s~TYzfA
KR z\ct|
i1sc oxX3\
/*Created on 2005-7-15*/ O,DA{> *m
package com.adt.service.impl; 6bU/IVP
)"q2DjfX*
import java.util.List; ,;{mH]"s
zZA I"\;W
import net.sf.hibernate.HibernateException; z? cRsqf
Q}1PPi,
import org.flyware.util.page.Page; ]zD/W%c
import org.flyware.util.page.PageUtil; <;acWT?(
yyZjMnuD
import com.adt.bo.Result; 5[I9/4,
import com.adt.dao.UserDAO; {9)LHX7dN
import com.adt.exception.ObjectNotFoundException; B\4SB
import com.adt.service.UserManager; @jjp\ ~
wCkkfTO
/** &yYK%~}t[
* @author Joa id*UTY
Tg
*/ J4x1qY)Y&v
publicclass UserManagerImpl implements UserManager { :yw0-]/DD
G*n5`N@>7
private UserDAO userDAO; 9WHkw@<R+
&&tQ,5H5
/** R*QL6t
* @param userDAO The userDAO to set. 9}5Q5OZ
*/ vL-%"*>v
publicvoid setUserDAO(UserDAO userDAO){ jd~r~.y
this.userDAO = userDAO; o6svSS
} U-|gtND
g*8sh
/* (non-Javadoc) )L^WD$"'Q
* @see com.adt.service.UserManager#listUser :egSW2"5S
whvM^
(org.flyware.util.page.Page) `oq
3G }
*/ koaH31Q
public Result listUser(Page page)throws ZfMJU
XD*$$`+#
HibernateException, ObjectNotFoundException { fv)-o&Q#
int totalRecords = userDAO.getUserCount(); B<_T"n'#b
if(totalRecords == 0) 4R^'+hy|?
throw new ObjectNotFoundException kigc+R
qk<tLvD_'
("userNotExist"); Th@L68
page = PageUtil.createPage(page, totalRecords); ~Fisno
List users = userDAO.getUserByPage(page); Ei}B9 &O
returnnew Result(page, users); jz/@Zg",
} O^
f[ugs
`qX'9e3VP+
} BEu9gu
'"=C^f
=TyN"0@
*}yW8i}36
2W|j
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其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 %B#Ewt@[
L(}T-.,Slr
询,接下来编写UserDAO的代码: $(C71M|CT
3. UserDAO 和 UserDAOImpl: :#b[gWl0Ru
java代码: BYwG\2?~
p2tBF98
c~dX8+
/*Created on 2005-7-15*/ (}bP`[@rX!
package com.adt.dao; ]`+>{Sx 1
a*=\-;HaZ
import java.util.List; dB< \X.
U4M!RdG
import org.flyware.util.page.Page; zYF'XB]4
&W }ooGg
import net.sf.hibernate.HibernateException; Lv#DIQ8y
DUY#RJf
/** 5P+3D{
* @author Joa H@OYtPHGR
*/ ~I2IgEj>]
publicinterface UserDAO extends BaseDAO { bCc^)o/w
#|2w^Kn
publicList getUserByName(String name)throws +-HaYB|p
`N2zeFG
HibernateException; 4uDz=B+8y
c1e7h l
publicint getUserCount()throws HibernateException; U
= T[-(:H
sL[,J[AN;
publicList getUserByPage(Page page)throws 4l[f}Z
5jkW@
HibernateException; `W{Ye=|[d#
}1epn#O_4
} -`#L rO;n
R (4 :_ xc
{Pu\KRU
N'|zPFkg
G8eAj%88
java代码: #jK{)%}mA
yQ6{-:`)
9/q4]%`
/*Created on 2005-7-15*/ ]Jm9D=
package com.adt.dao.impl; =suj3.
8v c4J5
import java.util.List; 5U%uS^%DP
:6Bk<
import org.flyware.util.page.Page; PK!=3fK4\F
D55dD>
import net.sf.hibernate.HibernateException; eDIjcZ
import net.sf.hibernate.Query; v5 $"v?PT
Uu8Z2M
import com.adt.dao.UserDAO; =<R77rnY&
V=.lpj9m
/** aCy2.Qn
* @author Joa naM4X@jl
*/ +g\u=&<6
public class UserDAOImpl extends BaseDAOHibernateImpl xlS
t
RG #
implements UserDAO { 7$;mkHu4H%
/?HRq ?n
/* (non-Javadoc) lvcX}{>\
* @see com.adt.dao.UserDAO#getUserByName Y#NlbKkzu
r'k-*I
(java.lang.String) !dSY?1>U<
*/ A]ciox$AjW
publicList getUserByName(String name)throws d;H1B/
HI)ks~E/
HibernateException { NCl$vc;,
String querySentence = "FROM user in class 19&!#z
Dy0cA| E
com.adt.po.User WHERE user.name=:name"; cA AJ7?
Query query = getSession().createQuery V=\&eS4^"
+X"TiA7{j
(querySentence); 6e/ 2X<O
query.setParameter("name", name); ~@MIG
return query.list(); [Gy sx
} BX2&tQSp
;sCX_`t0E
/* (non-Javadoc) 03AYW)"}M
* @see com.adt.dao.UserDAO#getUserCount() yz,ak+wp
*/ DJT)7l {
publicint getUserCount()throws HibernateException { jHTaG%oh
int count = 0; Y#3m|b45n
String querySentence = "SELECT count(*) FROM I?Eh
0fI
5|wQeosXxI
user in class com.adt.po.User"; hjaI&?w
Query query = getSession().createQuery q1`uS^3`
%\%1EZQ%
(querySentence); <iv9Mg}
count = ((Integer)query.iterate().next qdvGBdF
=}u;>[3
()).intValue(); Ui'~d(F
return count; ;m{[9i`2
} pBh[F5
J6rXbui$
/* (non-Javadoc) :G,GHU'/78
* @see com.adt.dao.UserDAO#getUserByPage H[fD
>
u;J9aKD
(org.flyware.util.page.Page) R~[
u|EC}
*/ ,|?B5n&
publicList getUserByPage(Page page)throws ^L<1S/~)
L&q~5 9
HibernateException { ps_CQh0
String querySentence = "FROM user in class ib*$3Fn~
5"]PwC
com.adt.po.User"; ~+V]MT
Query query = getSession().createQuery y/4 4((O
64o`7
(querySentence); Td
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query.setFirstResult(page.getBeginIndex()) >LwAG:Ud
.setMaxResults(page.getEveryPage()); -L</,>p
return query.list(); cD-\fRBGK
} hDjsGB|Fz
eW0:&*.vMj
} 2m/1:5
&=K-~!?
_QkU,[E
rL&585
c|hKo[r)
至此,一个完整的分页程序完成。前台的只需要调用 wF$8#=
#^%Rk'W
userManager.listUser(page)即可得到一个Page对象和结果集对象 /,$6`V
,K8PumM_
的综合体,而传入的参数page对象则可以由前台传入,如果用 Bn}@wO
q yQPR
webwork,甚至可以直接在配置文件中指定。 s[8<@I*u
/!d,f4n
下面给出一个webwork调用示例: <),FI <~
java代码: x{5I
]%"Z[R
U_Emp[
/*Created on 2005-6-17*/ RR*z3i`PP
package com.adt.action.user; &.K=,+0_R/
/,c9&it(M
import java.util.List; `61VP-r
M@
! {m
import org.apache.commons.logging.Log; (*^_wq-;
import org.apache.commons.logging.LogFactory; / QSK$ZDC
import org.flyware.util.page.Page; 3[-L'!pOX3
?v8B;="#w
import com.adt.bo.Result; VL7zU->
import com.adt.service.UserService; OfbM]:}<3
import com.opensymphony.xwork.Action; u
L/*,[}'
xAon:58m{
/** {6a";Xj\e
* @author Joa \/S?.P#L~
*/ }7wQFKME
publicclass ListUser implementsAction{ c3g\*)Jz"F
X;6&:%ZL@^
privatestaticfinal Log logger = LogFactory.getLog g>T'R Vb
+w%MwPC7`
(ListUser.class); ){L`hQ*=w
v|CRiwx
private UserService userService; J:M^oA'N:>
P_lk40X
private Page page; f:=q=i
}V6}>!Sb
privateList users; 9iUkvnphh
qwiM.b5
/*
*:_xy{m\
* (non-Javadoc) & i)p^AmM
* Cp_"PvTmT
* @see com.opensymphony.xwork.Action#execute() V:2|l!l*
*/ q#c\
publicString execute()throwsException{ +f;z{)%B
Result result = userService.listUser(page); *-ZJF6
page = result.getPage(); 7f~.Qus
users = result.getContent();
QU8?/
return SUCCESS; h9 [ov)
} ZYc)_Og
\; $j
"i&
/** kYmkKl_
* @return Returns the page. zl4Iq+5~6Q
*/ ]geO%m
public Page getPage(){ <G}>Gk8x
return page; {UvZ
} Nq9@^ E-{M
`:R8~>p
/** &5~bJ]P
* @return Returns the users. ,K,n{3]
*/ !1-:1Whz8
publicList getUsers(){ '<4/Md[
return users; FJ}/g
?
} ?.,..p
LmseY(i
N
/** P8:k"i/6J
* @param page q: ?6
* The page to set. 3{]csZvW
*/ cRI&cN"o
publicvoid setPage(Page page){ g.iiT/b
this.page = page; D-69/3 PvP
} [
!].G=8
6rq:jvlx$
/** ;[uJ~7e3
* @param users bX=A77
* The users to set. OF2*zU7M
*/ 3K_J"B*7
publicvoid setUsers(List users){ h/QZcA
this.users = users; 65)/|j+
} |9@?8\
>#)^4-e
/** !QSL8v@c
* @param userService Jx.Jx~
* The userService to set. Y'DI@
*/ Z ZX|MA!
publicvoid setUserService(UserService userService){ 1<Qb"FN!2
this.userService = userService; [59_n{S 1
} /MosE,7l
} k-*H=km
L|u\3.:
D0.7an6
;SagN
|Q@4F&k
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, ~Yb5FYE
d3St Z~&r!
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 `!K(P- yB?
Xt_8=Q
么只需要: x32hO;
java代码: #||^l_
)4toBDg"
6`J*{%mP
<?xml version="1.0"?> pi7W8y
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork %7xx"$P:R
SRRqIQz
1.0//EN" "http://www.opensymphony.com/xwork/xwork- !NuiVC]
.-awl1 W
1.0.dtd"> 9i;%(b{
N>/!e787OU
<xwork> ;xS@-</:
P\pHos
<package name="user" extends="webwork- ^mv F%"g
[U5[;BNRD
interceptors"> |k\4\aLj
_)"-zbh}{
<!-- The default interceptor stack name SDwTGQ/0
^KM' O8
--> wDVKp['
<default-interceptor-ref bC{}&a
>7V96jL$Y
name="myDefaultWebStack"/> ^Vso`(Ss
!KKkw4
<action name="listUser" =\"88e;b2
3X=9$xw_
class="com.adt.action.user.ListUser"> K`{P/w
<param PzMJ^H{
m(i8 4~
name="page.everyPage">10</param> /Nt#|C>
<result 4>-'w MW")
MxQhkY-=
name="success">/user/user_list.jsp</result> Ye% e!
</action> ikX"f?Q;S2
BiT
#bg
</package> @.0>gmY;:
_kg<KD=P
</xwork> SR!EQ<
_2xNio&
-K eoq
z6)b XL[f
*:gx1wd
t~]n"zgovz
这样就可以通过配置文件和OGNL的共同作用来对page对象设置初值 rofj&{w
`u$
Rd
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。 H=RzY-\a%
LeRyS]
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 3`.*~qW
3qujz)o
hjf!FY*F
DA]<30w
(VV5SvdE
我写的一个用于分页的类,用了泛型了,hoho 6
<XQ'tM]N
o&0fvCpW
java代码: ;-sZaU;
FjR/_GPo6
MdXOH$ps
package com.intokr.util; !IF]P#
=1sGT;>
import java.util.List; fIe';a
Z.'j7(tu
/** QOiPDu=8z
* 用于分页的类<br> v=5H,4UMA
* 可以用于传递查询的结果也可以用于传送查询的参数<br> HVjN<H IqM
* Pt5"q3ec{T
* @version 0.01 A0X'|4I
* @author cheng mh#NmW>n
*/ 6Cw+
public class Paginator<E> { /5:2g#S4
privateint count = 0; // 总记录数 epN>;e z
privateint p = 1; // 页编号 !iv6k~.e'2
privateint num = 20; // 每页的记录数 ]Q0m]OaT
privateList<E> results = null; // 结果 ~&HP}Q$#f
^/]w}C#:d
/** M^IEu}
* 结果总数 ?#s9@R1
*/ -&q@|h'
publicint getCount(){ cD.afy
return count; !ZNirvk
} J([Y4Em5
Y*VF1M,2_
publicvoid setCount(int count){ 3bYPi^
this.count = count; &s6;2G&L$
} b'q ru~i
X* 4C?v
/** I+2#k\y
* 本结果所在的页码,从1开始 gy5 ^JL
* GmhfBW?
* @return Returns the pageNo. P* X^)R
*/ oZ,J{I!L
publicint getP(){ B7x(<!B
return p; 5PY4PT=G
} ;k?Z,M:
'Em3;`/C*+
/** n?Zt\Kto
* if(p<=0) p=1 >0F)^W?
* ncGt-l<9
* @param p #`]`gNB0Yg
*/ ej91)3AO
publicvoid setP(int p){ j]HzI{7y
if(p <= 0) :2t0//@X
p = 1; ='A VI-go5
this.p = p; <+y%k~("
} Es<& 6
;*%3J$T+
/** ,J6t
1V
* 每页记录数量 YCl&}/.pA
*/ E)3Ah!
publicint getNum(){ e5AZU7%.
return num; \LG0
} IA%|OVAfF
:o3>
/** p=!12t
* if(num<1) num=1 []lMv
ZW
*/ X9
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publicvoid setNum(int num){ 3</W}]$)p
if(num < 1) M^ZEAZi
num = 1; p40;@gUug
this.num = num; *@I/TX'\rY
} 0tKVo]EK
~3&*>H^U
/** V15/~
* 获得总页数 NufRd/q
*/ ="p,~ivrz
publicint getPageNum(){ aT4I sPA?_
return(count - 1) / num + 1; uG7?:) pxv
} vpq"mpfkh
j>8S,b=%
/** n'To:
* 获得本页的开始编号,为 (p-1)*num+1 "D,}|
*/ &=*sN`
publicint getStart(){ R$h
B9BK
return(p - 1) * num + 1; 2c*w{\X
} /
Q| Z&-c
B?%e-xV-
/** 15z(hzU?#
* @return Returns the results. jl>jy6T
*/ 0fGt7 "Q
publicList<E> getResults(){ xX?9e3(
return results; d>gQgQ;g
} r>#4Sr
frokl5L@
public void setResults(List<E> results){ 2BKiA[
;;
this.results = results; kyi"U A82
} +iqzj-e&e[
4|&_i)S-Y
public String toString(){ ::p%R@?
StringBuilder buff = new StringBuilder QE|x[?7e,!
(gRTSd T?
(); mEmgr(W
buff.append("{"); Cxd^i
buff.append("count:").append(count); *ESi~7;#
buff.append(",p:").append(p); ]GT+UX
buff.append(",nump:").append(num); >*/:"!u
buff.append(",results:").append }Ug$d>\
+~>cAWZq_
(results); G#Kw6
buff.append("}"); 1Ep7CV-n}
return buff.toString(); I5*<J n
} m\oxS;fxWi
;m=k
FZ?
} e45)t}'
"8p<NsU
>Hu3Guik]