Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 r\+AeCyb"p
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 Yyl2J#$!
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据这一功能,我设计了通用的抽象Bean基类和分页类支持,代码来 o?P(Fuf
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自于Quake Wang的javaeye-core包的相应类,然后又做了很多修改 (,\`?g
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。 LV=!nF0
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分页支持类: IsO'aFK)ln
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java代码: 6<A\U/
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package com.javaeye.common.util; S5RS?ya
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import java.util.List; :i*JlKHJd
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publicclass PaginationSupport { 6"
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publicfinalstaticint PAGESIZE = 30; xPqpNs-,
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privateint pageSize = PAGESIZE; @6.1EK0
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privateList items; Uk ?V7?&
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privateint totalCount; `Y.RAw5LrE
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privateint[] indexes = newint[0]; ]-{T-*h:
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privateint startIndex = 0; 4)9X) Qx
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public PaginationSupport(List items, int hUGIy(
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totalCount){ Q*$x!q
setPageSize(PAGESIZE); xKsn);].`
setTotalCount(totalCount); |#5JI#,vX
setItems(items); 1t!Mg{&e[x
setStartIndex(0); ,`+y4Z6`W2
} @b!fs
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public PaginationSupport(List items, int "hog A5=
s'\"%~nF<
totalCount, int startIndex){ )IZ$R*Y{
setPageSize(PAGESIZE); Ev0V\tl>0
setTotalCount(totalCount); s3kh (N
setItems(items); mq'q@@:c
setStartIndex(startIndex); W,Dr2$V
} (a7IxW
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public PaginationSupport(List items, int !h9 An
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totalCount, int pageSize, int startIndex){ ci3{k"
setPageSize(pageSize); qLYv=h$,
setTotalCount(totalCount); z8z U3?
setItems(items); %t+V8A
setStartIndex(startIndex); I8^z\ef&
} sMO3eNLn
d G:=tf&1R
publicList getItems(){ 4TR:bQZs
return items; &5d>jEaB}
} ol`]6"Sc
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publicvoid setItems(List items){ Ii|<:BW
this.items = items; NmtBn^t
} Pi*,&D>{7
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publicint getPageSize(){ kt;X|`V{5z
return pageSize; ~=c^Oo:
} n }MG
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publicvoid setPageSize(int pageSize){ kV<VhBql!
this.pageSize = pageSize; OH=Ffy F,
} ]Uxx_1$,
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publicint getTotalCount(){ g]d"d
return totalCount; >Xb]n_`
} _r,# l5~U
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publicvoid setTotalCount(int totalCount){ $V\xN(Ed
if(totalCount > 0){ =~HX/]zF
this.totalCount = totalCount; 6(ja5)sn*
int count = totalCount / has5"Bb
+JQN=nTA
pageSize; d0N7aacY
if(totalCount % pageSize > 0) fYCAwS{
count++; 7CQ48LH]
indexes = newint[count]; ,%ajIs"Gi
for(int i = 0; i < count; i++){ kF\QO
[
indexes = pageSize * \<z{@
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i; 8H{@0_M
} 8o4
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}else{ Fir7z nRW
this.totalCount = 0; LL,~&5{
} @7BH`b$)!
} Pp.X Du
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publicint[] getIndexes(){ =RQ>q
return indexes; Ajq<=y`NzV
} *?i~AXJm
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publicvoid setIndexes(int[] indexes){ ?. ~@ lE
this.indexes = indexes; w\\
} WRo#ZVt9$
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publicint getStartIndex(){ rN>f"/J
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return startIndex; naAZR*(A
} U:IQWl C
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publicvoid setStartIndex(int startIndex){ 5$9j&&R
if(totalCount <= 0) Pu}2%P)p
this.startIndex = 0; r?[Zf2&
elseif(startIndex >= totalCount) &{7%VsTB
this.startIndex = indexes `VS/Xyp
wt RAq/
[indexes.length - 1]; b
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elseif(startIndex < 0) _\u'~wWl
this.startIndex = 0; 'jfI1 ]q
else{ RJSNniYr7
this.startIndex = indexes gIT"nG=a4
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[startIndex / pageSize]; ^#_@Kq%th
} '{C=vW
} r_Xk:
i\N,4Fdor
publicint getNextIndex(){ LnM+,cBz
int nextIndex = getStartIndex() + C/lpSe
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pageSize; 539[,jH
if(nextIndex >= totalCount) UXe @c@3
return getStartIndex(); Q?Q!D+~mND
else _jP]ifu`
return nextIndex; _W&.{
7
} "-\I?k
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publicint getPreviousIndex(){ Pq !\6s@
int previousIndex = getStartIndex() - \vpUl
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pageSize; gh3_})8c
if(previousIndex < 0) l8jm7@.E
return0; V\4'Hd
else _18) XR
return previousIndex; !$Nh:(>:
} 1XL^Zhr
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} ,D;d#fJ
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抽象业务类 kpLDK81I
java代码: RQ!kVM@
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/** ~"#qG6dP
* Created on 2005-7-12 SwXVa/9a"
*/ 'de&9\
package com.javaeye.common.business; ,F!zZNW9
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import java.io.Serializable; mA@FJK_
import java.util.List; :Ugf3%sQ
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import org.hibernate.Criteria; `-/-(v+ i
import org.hibernate.HibernateException; C6Lc
import org.hibernate.Session; SYkwM6
import org.hibernate.criterion.DetachedCriteria; gNUYHNzDM(
import org.hibernate.criterion.Projections; u5;;s@{Ye4
import jmPnUn
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org.springframework.orm.hibernate3.HibernateCallback; JuQwZ]3ed
import N?`V;`[
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org.springframework.orm.hibernate3.support.HibernateDaoS hK+6S3-Ez
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upport; !mHMFwvS
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import com.javaeye.common.util.PaginationSupport; 0xVw{k}1U
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public abstract class AbstractManager extends 'HKDGQl`
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HibernateDaoSupport { v|\3FEu@
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privateboolean cacheQueries = false; ]-8WM5\qJM
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privateString queryCacheRegion; '_d4[Olu
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publicvoid setCacheQueries(boolean V6Mt;e)C
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cacheQueries){ mww<Xm'
this.cacheQueries = cacheQueries; =PU($
} TZ *>MySiF
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publicvoid setQueryCacheRegion(String B*Q 9g r
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queryCacheRegion){ CYRZ2Yrk?"
this.queryCacheRegion = T/a=z
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queryCacheRegion; ^M{,{bG
} G54J'*Z
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publicvoid save(finalObject entity){ q3AqU?f
getHibernateTemplate().save(entity); 0:f]&Ng
} dgL>7X=7
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publicvoid persist(finalObject entity){ w
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getHibernateTemplate().save(entity); K>dB{w#gS
} 9.8%Iw
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publicvoid update(finalObject entity){ #l ZK_N|1x
getHibernateTemplate().update(entity); V(_1q
} l% T4:p4e
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publicvoid delete(finalObject entity){ E7t;p)x
getHibernateTemplate().delete(entity); ?u|@,tQ[
} #obRr#8
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publicObject load(finalClass entity, VGmvfhf#"
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finalSerializable id){ [ n7>g
return getHibernateTemplate().load z$e6T&u5B
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(entity, id); &^r>Q`u
} gxN>q4z
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publicObject get(finalClass entity, N7?B"p/
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finalSerializable id){ O2?C *
return getHibernateTemplate().get _dJ(h6%3
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(entity, id); ;f=m+QXU
} Snx!^4+MF
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publicList findAll(finalClass entity){ t:2v`uk
return getHibernateTemplate().find("from flsejj$
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" + entity.getName()); c-sjYJXKM*
} {_QdB;VwH
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publicList findByNamedQuery(finalString xG9Sk
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namedQuery){ +(W1x
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return getHibernateTemplate `Mnu<)v
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().findByNamedQuery(namedQuery); Xw-[Sf]p
}
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publicList findByNamedQuery(finalString query, j3gDGw;
Bq q=2lj
finalObject parameter){ S6TNu+2w4
return getHibernateTemplate Vw;Z0_C
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().findByNamedQuery(query, parameter); <$A,Ex94
} i[v4[C=WB!
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publicList findByNamedQuery(finalString query, P {TJ$
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finalObject[] parameters){ 0l!#u`cCI
return getHibernateTemplate g!'R}y
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().findByNamedQuery(query, parameters); VdLoi\-/L
}
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publicList find(finalString query){ "
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return getHibernateTemplate().find p3I"LY
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(query); (}: s[cs
} L:z0cvn"
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publicList find(finalString query, finalObject ekM?
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parameter){ /^.|m3
return getHibernateTemplate().find ]Bhy=1
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(query, parameter); 3H,E8>Vd
} "6B7EH
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public PaginationSupport findPageByCriteria h>N}M}8
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(final DetachedCriteria detachedCriteria){ 64s;EC
return findPageByCriteria C|'DKT4M&
8bIP"!=*W
(detachedCriteria, PaginationSupport.PAGESIZE, 0); o/5-T4
} -%nD'qy,.
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public PaginationSupport findPageByCriteria ^Q6J$"Tj
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(final DetachedCriteria detachedCriteria, finalint FFHq':v
p>6`jr
startIndex){ D /eH~
return findPageByCriteria ,_[x|8m
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(detachedCriteria, PaginationSupport.PAGESIZE, 9&6j uL
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startIndex); +H)'(<
} r*X,]\V0x
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public PaginationSupport findPageByCriteria \2SbW7"/;P
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(final DetachedCriteria detachedCriteria, finalint $( hT{C,K
/ 3A6xPOg
pageSize, $=aO*i
finalint startIndex){ v2T2/y%
return(PaginationSupport) tne_]+
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getHibernateTemplate().execute(new HibernateCallback(){ LPk@t^[
publicObject doInHibernate s**<=M GK
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(Session session)throws HibernateException { Z;0~f<e%
Criteria criteria = Jt~Ivn,
]
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detachedCriteria.getExecutableCriteria(session); YQVo7"`%
int totalCount = 6j#JhcS+
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((Integer) criteria.setProjection(Projections.rowCount .RD<]BxJ
wxN)dB
()).uniqueResult()).intValue(); J<)qw
criteria.setProjection 53Adic
o)`PSw=
(null); @s5=6z]=H
List items = %X}ZX|{ O
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criteria.setFirstResult(startIndex).setMaxResults #-{<d%qk
b@CB +8$
(pageSize).list(); `e[S Zj\
PaginationSupport ps = SV7;B?e%Y
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new PaginationSupport(items, totalCount, pageSize, KK|w30\f
d;i|s[6ds`
startIndex); %?~'A59
return ps; ycA<l"
} \#sD`O
}, true); qwTz7r
} 3m1g"
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public List findAllByCriteria(final
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DetachedCriteria detachedCriteria){ 8|&,JdT
return(List) getHibernateTemplate WMbkKC.{J
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().execute(new HibernateCallback(){ oFk2y ^>u
publicObject doInHibernate l;8t%JV5
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(Session session)throws HibernateException { y\Wn:RR1 [
Criteria criteria = "be\%W+<
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detachedCriteria.getExecutableCriteria(session); q^X7x_
return criteria.list(); sz7*x{E
} 5eAZfe%H
}, true); n Ja!&G&
} vHaM yA-
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public int getCountByCriteria(final X$};K\I
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DetachedCriteria detachedCriteria){ =vThtl/azD
Integer count = (Integer) RB>=#03
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getHibernateTemplate().execute(new HibernateCallback(){ ]:%DDlRb
publicObject doInHibernate VZ]iep
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(Session session)throws HibernateException { Sv =YI
Criteria criteria = Y;w|Fvjj+
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detachedCriteria.getExecutableCriteria(session); Jb,54uN
return k@xinK%O{
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criteria.setProjection(Projections.rowCount If'q8G3]-
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()).uniqueResult(); ]w *"KG!(
} 5:PS74/
}, true); \zd[A~!
return count.intValue(); \((MoQ9Qk
} |n_N.Z
} #p+iwW-
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用户在web层构造查询条件detachedCriteria,和可选的 Y9BQLu4F
# epP~J_f
startIndex,调用业务bean的相应findByCriteria方法,返回一个 eKLvBa-{@
O_ _s~
PaginationSupport的实例ps。 3f=ZNJ>
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ps.getItems()得到已分页好的结果集 tSy 9v
ps.getIndexes()得到分页索引的数组 w!lk&7Q7Z
ps.getTotalCount()得到总结果数 =r]l"T
ps.getStartIndex()当前分页索引 _2KIe(,;
ps.getNextIndex()下一页索引 L|1,/h
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ps.getPreviousIndex()上一页索引 NQD5=/o
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 P!-RZEt$
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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 *VsGa<V
-1Tr!I:1
一下代码重构了。 6UCF w>
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我把原本我的做法也提供出来供大家讨论吧: cr;:5D%_
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首先,为了实现分页查询,我封装了一个Page类: MK3h~`is
java代码: {.Qv1oOa
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/*Created on 2005-4-14*/ _Q:z -si
package org.flyware.util.page; .B~}hjOZK
kq X=3Zo
/** UIDeMz
* @author Joa Muwlehuq
* WVD48}HF-
*/ (:8a6=xQ
publicclass Page { OPN\{<`*d
D\M"bf>q1
/** imply if the page has previous page */ -ED}
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privateboolean hasPrePage; .@): Uh
NCh-BinK@
/** imply if the page has next page */ a/uo)']B
privateboolean hasNextPage; a4UwhbH
*rTg>)
/** the number of every page */ /4O))}TX
privateint everyPage; GXxI=,L8F
U;/2\Ii
/** the total page number */ n
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privateint totalPage; ,c"J[$i$
^?RH<z
/** the number of current page */ lrZ]c:%k
privateint currentPage; s! 2[zJ19p
*EGzFXa
/** the begin index of the records by the current FD[*Q2fU
^R:&c;&,
query */ ~;9n6U
privateint beginIndex; c #TY3Z|
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/** The default constructor */ <oJ?J^
public Page(){ ?fH1?Z\'K
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} "LTw;& y
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/** construct the page by everyPage
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* @param everyPage sJx_X8
* */ Ea
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public Page(int everyPage){ #&T O(bk
this.everyPage = everyPage; _%R^8FjH*
} 3}FZg
w .
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/** The whole constructor */ W6T4Zsg
public Page(boolean hasPrePage, boolean hasNextPage, ^7\kvW
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int everyPage, int totalPage, @=l6zd@
int currentPage, int beginIndex){ \_O#M
this.hasPrePage = hasPrePage; }|
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this.hasNextPage = hasNextPage; ~2\Sn-`
this.everyPage = everyPage; !b_(|~7Lc
this.totalPage = totalPage; }?,YE5~
this.currentPage = currentPage; D&pn@6bB
this.beginIndex = beginIndex; }O7sP^
} 5e.aTW;U
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/** dJ
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* @return g
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* Returns the beginIndex. LUD.
*/ IrQ.[?C
publicint getBeginIndex(){ vN^.MR+<
return beginIndex; 2c]"*Pb
} 1W'Ai"DLw
%\
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/** 4*qBu}(
* @param beginIndex 0Qa0
* The beginIndex to set. aGC3&c[Wx
*/ _M/N_Fm
publicvoid setBeginIndex(int beginIndex){ <~5O-.G]
this.beginIndex = beginIndex; l+@;f(8}
} g8uqW1E^
>fWGiFmlk
/** E;CM"Y*
* @return SPE)db3
* Returns the currentPage. :W, S
*/ fYjmG[4
publicint getCurrentPage(){ Ur#jJR@%3
return currentPage; ywJ [WfCY
} N\*oL*[j
IMwV9rF
/** A
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* @param currentPage nSyLt6zn\
* The currentPage to set. X3G593ts
*/ @$r[$D
v
publicvoid setCurrentPage(int currentPage){ .4^+q9M
this.currentPage = currentPage; ? Vd~
} 9k ~8n9
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/** iSO xQ
* @return ={%'tv`
* Returns the everyPage. T"{~mQ*
*/ A#cFO)"
publicint getEveryPage(){ J[:#(c&c!1
return everyPage; 5kw
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} |p[Mp:^^
]]:K
l
/** T;(,9>Qsu
* @param everyPage pYQSn.`V~
* The everyPage to set. IrL7%?
*/ +8zACs{p
publicvoid setEveryPage(int everyPage){ m8F$h-
this.everyPage = everyPage; yZ6WbI8n
} <8 <P,
c
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/** "'[M~Js
* @return +h"i6`g
* Returns the hasNextPage. y[$UeE"0
*/ k*;U?C!
publicboolean getHasNextPage(){ fQib?g/G
return hasNextPage; Wd7*7']
} Z0Sqw
kEq~M10
/** !O"2)RU1
* @param hasNextPage A[m?^vk q
* The hasNextPage to set. ?MFC(Wsh
*/ ]\fHc"/
publicvoid setHasNextPage(boolean hasNextPage){ 8i]
S[$Fc
this.hasNextPage = hasNextPage; DL V ny]
} aQ(P#n>a2
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/** P
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* @return w&H>`l06
* Returns the hasPrePage. >oq\`E
*/ Q<6* UUQm
publicboolean getHasPrePage(){ t8RtJ2;
return hasPrePage; {H,O@
} /95z1e
t }4
/** G_=i#Tu[
* @param hasPrePage _"p(/H
* The hasPrePage to set. vGsAM*vw6
*/ %G(VYCeK
publicvoid setHasPrePage(boolean hasPrePage){ mxCneX
this.hasPrePage = hasPrePage; EFDmNud`Q
} cRKLyb
SN"Y@y)=
/** 1@I#Fv
* @return Returns the totalPage. |s/Kb]t
* MjQ>&fUK
*/ gcwJ{&
publicint getTotalPage(){ O=}
return totalPage; mW)kWuOO
}
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/** N4qBCBr(
* @param totalPage rg[#(
* The totalPage to set. ,]JIp~=nsh
*/ a'HHUii=
publicvoid setTotalPage(int totalPage){ LsGO~EiJ
this.totalPage = totalPage; "MzBy)4Q
} d\Up6F
;K l'[~z
} B:i$
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'Kmf6iK>[
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上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 4+>~Ui_#
pdN8hJ
个PageUtil,负责对Page对象进行构造: V`/c#y||
java代码: fZap\
Xeja\5zB
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/*Created on 2005-4-14*/ W4qT]m
package org.flyware.util.page; ae3 Gn}tf
w"kBAi&
import org.apache.commons.logging.Log; .j)DE}[q>
import org.apache.commons.logging.LogFactory; :`BG/
| LZ+_
/** @QpL*F
* @author Joa RK&RMN8@
* yHf^6|$8
*/ /i!/)]*-
publicclass PageUtil { 3# 0Nd"/0
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privatestaticfinal Log logger = LogFactory.getLog @GweNo`p7
;x|?N*
(PageUtil.class); @Z""|H"0
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/** %dd B$(
* Use the origin page to create a new page R4[|f0l}s
* @param page r<dvo%I#|
* @param totalRecords >Wd=+$!I
* @return Q'e[(^8
*/ './qBJ
publicstatic Page createPage(Page page, int ?6\A$?
l,QO+
>)z
totalRecords){ ucLh|}jJ5
return createPage(page.getEveryPage(), v~dUH0P<>e
Y!u">M#@
page.getCurrentPage(), totalRecords); cE,,9M@^
} C91'dM
U6nC
<3f
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/** <&1hJ)O
* the basic page utils not including exception ZOJ7^g
1OK~*=/4
handler u]3VK
* @param everyPage FePWr7Ze
* @param currentPage Zq/=uB7Z
* @param totalRecords i@YM{FycX
* @return page 5.Nc6$
N
*/ cbx(
L8
publicstatic Page createPage(int everyPage, int /-ewCCzZV
j4D`Xq2X
currentPage, int totalRecords){ =~$)Ieu
everyPage = getEveryPage(everyPage); y2x)<.cDP
currentPage = getCurrentPage(currentPage); 3)dtl!VMW[
int beginIndex = getBeginIndex(everyPage, rY=dNK]d
Eds{-x|10
currentPage); ]<o^Q[OL
int totalPage = getTotalPage(everyPage, 2cJ3b
0Xx
sGbk4g
totalRecords); u,S}4p&l
boolean hasNextPage = hasNextPage(currentPage, `hl1R3nBM
Oufdi3h
totalPage); KSl@V>!_
boolean hasPrePage = hasPrePage(currentPage); -hO[^^i9
p@=B\A]
returnnew Page(hasPrePage, hasNextPage, ;u?H#\J,
everyPage, totalPage, 1GgG9I
currentPage, 4,6nk.$yN
}z wHUf9q1
beginIndex); Ha!]*wg#
} ^: V6=
BxXP]od
privatestaticint getEveryPage(int everyPage){ l`<u\],
return everyPage == 0 ? 10 : everyPage; @arMg2"o
} l*4_
-*"Q-GO
privatestaticint getCurrentPage(int currentPage){ I/w=!Ih
return currentPage == 0 ? 1 : currentPage; %-, -:e
} lJXihr
Eh?,-!SUQn
privatestaticint getBeginIndex(int everyPage, int JdA3O{mT)
vZ2/>}!Z=
currentPage){ @D&}ZV=J
return(currentPage - 1) * everyPage; hQDZ%>
} wWUt44:0O
J*'#!
xIa
privatestaticint getTotalPage(int everyPage, int d"4J)+q
tcS7 @^'
totalRecords){ x[H9<&)D
int totalPage = 0; [n;GP@A]R
|R$/oq
if(totalRecords % everyPage == 0) p7Q
%)5o
totalPage = totalRecords / everyPage; d+:pZ
else n42XqR
totalPage = totalRecords / everyPage + 1 ; 1Igo9rv
=L?(mNHT
return totalPage; <gc\,P<ru
} hiA%Tq?
Rd{#cW~
privatestaticboolean hasPrePage(int currentPage){ j; )-K 3Ia
return currentPage == 1 ? false : true; =WP`i29j9}
} vL:tuEE3
Hb{G
RG70
privatestaticboolean hasNextPage(int currentPage,
d365{
)'gO?cN
int totalPage){ C'jE'B5b
return currentPage == totalPage || totalPage == Qh.
:
N
a6fqtkZ x
0 ? false : true; 00)=3@D
} jZvQMW
8g CQ0w<
]f"l4ay@M
} x_TtS|
,k5b,}tN
G_UxR9Qo
%4rPkPAtrp
8 m
T..23
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 }28,fb
/
F)g.xQ
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 92HxZ*t7km
d;10[8:5=
做法如下: R@)L@M)u;
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 ]ZOzqh_0C
`CXAE0Fx
的信息,和一个结果集List: SecZ5(+=
java代码: - &/n[EE
=9ISsI\Y6
D.\s mk
/*Created on 2005-6-13*/ :{Crc
package com.adt.bo; J3B]JttU
T m0m$l
import java.util.List; 'YcoF;&[C
gqf*;Z eU
import org.flyware.util.page.Page; T] tG,W1>i
[:!D.@h|
/** g^EkRBU
* @author Joa ^KK6 d
*/ a:(.{z?nM
publicclass Result { H,!3s<1
?!J{Mrdn
private Page page; m
pWmExQ
K8UgP?c;0
private List content; BiUOjQC#
.v3~2r*&
/** YQI&8~z
* The default constructor nUL8*#p-
*/ s2-p-n
public Result(){ pU |SUM
super(); l}$Pv?T,2
} /J"U`/
{4
[z1[4
/** 0V&6"pF_Y'
* The constructor using fields ]`2=<n;=
* 62 biOea
* @param page Z+< zKn}
* @param content k-b0Eogp]
*/ 2vit{
public Result(Page page, List content){ PfI~`ke
this.page = page; Gn*vVZ@`x
this.content = content; "Oh(&N:U
} iS{8cN3R
y:N
QLL>
/** >e7w!v]
* @return Returns the content. ;nPjyu'g
*/ =2z9Aq{
publicList getContent(){ :{d?B$
return content; "@JSF
} q>T7};5m2
8yH*
/** ?vgHu
* @return Returns the page. ]KS|r+
*/ i$Q$y
hT{
public Page getPage(){ 2U-F}Z
return page; Qifjv0&;u
} G6N$^HkW?
h] (BTb#-
/** qd9CKd
* @param content mE"?{~XVL
* The content to set. (YbRYu
*/ S[bFS7[
public void setContent(List content){ Q]Fm4
this.content = content; 'Lw4jq
} z@nJ-*'U8
pm-SDp>s
/** Kzw)Q
* @param page H
h4G3h0
* The page to set. F]hKi`@
*/ l%?D%'afN
publicvoid setPage(Page page){ ==[a7|q
this.page = page; $ePBw~yu
} I$o^F/RH
} *;~*S4/P
/ ;U
B*+3A!{s
idLysxN
QeYO)sc`
2. 编写业务逻辑接口,并实现它(UserManager, HCh;Xi
@Fp-6J
UserManagerImpl) !vU$^>zo~
java代码: L- -
b5hJaXJN
Kp+Lk
/*Created on 2005-7-15*/ q][{?
package com.adt.service; *[Ld\lRj
+X4O.6Mn
import net.sf.hibernate.HibernateException; OIK14D:
,r{[l D^
import org.flyware.util.page.Page; ps#+i
&R54?u^A
import com.adt.bo.Result; s6(iiB%d
D{&0r.2F
/** 8#OcrJzC
* @author Joa ~:Jw2 P2z
*/ Jl^Rz;bQ-
publicinterface UserManager { x(/KHpSWK
h)EHaaf
public Result listUser(Page page)throws SCClD6k=V
[b:$sR;
HibernateException; ~RV>V*l
} PD]e*z{Z
} ?j^[7
IR (6
o0Z(BTO
+?[,y
78v4cQ Y
java代码: LFsrqdzJ
U!E
SMr
]Gf.
/*Created on 2005-7-15*/ i2ap]
package com.adt.service.impl; 4WV'\R+m
W?;kMGW-
import java.util.List; UXz0HRRS0
B!|<<;Da6
import net.sf.hibernate.HibernateException; ~c>* 3*
-jc8ku3*
import org.flyware.util.page.Page; (3YI> /#
import org.flyware.util.page.PageUtil; ^`Tns6u>
~c~$2Xo
import com.adt.bo.Result; PiD%PBmUl
import com.adt.dao.UserDAO; HH>"J/;c,
import com.adt.exception.ObjectNotFoundException; cTO\Vhg
import com.adt.service.UserManager; 8Wn;U!qT
wN [mU
/** ;2||g8'
* @author Joa -c-#1_X5
*/ C WJGr:}&
publicclass UserManagerImpl implements UserManager { {Mc^[}9
:` >|N|i
private UserDAO userDAO; V[<]BOM\v
j?&Rf,,%
/** NZ(c>r6
* @param userDAO The userDAO to set. MS~c
$
*/ C9-IJj
publicvoid setUserDAO(UserDAO userDAO){ 5T?esF<
this.userDAO = userDAO; jtdhdA
} j9zK=eG
]UG+<V
,:
/* (non-Javadoc) ]Mu
+
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* @see com.adt.service.UserManager#listUser 74VN3m
3[kY:5-
(org.flyware.util.page.Page) KX e/i~AS
*/ - aCtk$3
public Result listUser(Page page)throws l0Myem
v?z
Cx $M
HibernateException, ObjectNotFoundException { <szD"p|K
int totalRecords = userDAO.getUserCount(); nJJ9>#<g$
if(totalRecords == 0) >hcA:\UPk
throw new ObjectNotFoundException VeixwGZ.
)3_I-Ia
("userNotExist"); \%nFCK0
page = PageUtil.createPage(page, totalRecords); $dAQ'\f7
List users = userDAO.getUserByPage(page); HC0q_%j
returnnew Result(page, users); aa8xo5tIp
} gxEa?QH
-!uut7Z|
} CmaV>
2|vArRKt
>}#h
&61;v@
7Y$#*
7
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 W2L:
D9H(kk
询,接下来编写UserDAO的代码: {R[FwB^7wJ
3. UserDAO 和 UserDAOImpl: F|K=].
java代码:
rn^7B-V
O>)<w
Ms`
2s, [DC
/*Created on 2005-7-15*/ Bl5*sfjG
package com.adt.dao; J /3qJst
ZMmaM "9
import java.util.List; l[=7<F
YQ}xr^VA
import org.flyware.util.page.Page; t^0^He$Ot
e)dPv:oK3
import net.sf.hibernate.HibernateException; l4+!H\2
xaO9?{O
/** TJ@@kSSbl
* @author Joa 3F' {JP
*/ H`/QhE
publicinterface UserDAO extends BaseDAO { W=T3spV
KlMrM% ;y
publicList getUserByName(String name)throws %}
WSw~X
y2k'^zE
HibernateException; jU2Dpxkt
%Gp%l
publicint getUserCount()throws HibernateException; Jz D
Mx?
W:q79u yX
publicList getUserByPage(Page page)throws }Z
T{
$:M *$r^u
HibernateException; Jy)E!{#x
wD|,G!8E2
} #L}YZ
C3kxw1*
m,nZrap
a.+2h%b
c|<*w[%C
java代码: :fI|>I
~
'< ]:su+
" , c1z\
/*Created on 2005-7-15*/
#:0dqD=
package com.adt.dao.impl; Wx#((T
<
aeBhg%
import java.util.List; g z!q
y+f@8]
import org.flyware.util.page.Page; ( lbF/F>v
oJC-?
import net.sf.hibernate.HibernateException; OgJd^
import net.sf.hibernate.Query; su]CaHU
tydD~a
import com.adt.dao.UserDAO; GOJ*>GpS
cU8Rm\?
/** }X{#=*$GQ
* @author Joa ,4oYKJ$+h
*/ x2p}0N
public class UserDAOImpl extends BaseDAOHibernateImpl E"!I[
7'wt/9
implements UserDAO { ~=h M y`Ml
CJ B
/* (non-Javadoc) {~.~ b+v
* @see com.adt.dao.UserDAO#getUserByName `f.okqBAh
Fu4LD-#
(java.lang.String) ^lVZW8
*/ @y%4BU&>0
publicList getUserByName(String name)throws n4Fh*d ixg
aty"6~
HibernateException { 4Q2=\-KFj
String querySentence = "FROM user in class }7iWm XlI
PI{;3X}9$,
com.adt.po.User WHERE user.name=:name"; ;J|sH>i
Query query = getSession().createQuery JmDi{B?
j^ L"l;m
(querySentence); MhMY"bx8
query.setParameter("name", name); )cA#2mlS'1
return query.list(); Jy&O4g/'5
} [{.e1s<EK
Q 6djfEN>
/* (non-Javadoc) OiI[w8
* @see com.adt.dao.UserDAO#getUserCount() #<ppiu$
*/ r|$@Wsb?#
publicint getUserCount()throws HibernateException { ~(E.$y7P
int count = 0; }{>)2S
String querySentence = "SELECT count(*) FROM qfp,5@p
e~tgd8a2a
user in class com.adt.po.User"; %lVc7L2]
Query query = getSession().createQuery lej-,HX
i#/,Q1yEn
(querySentence); 2NS(;tBB0
count = ((Integer)query.iterate().next 'n`+R~Kkh
; MU8@?yN
()).intValue(); FEqs4<}E
return count; (XtN3FTY
} eQh@.U*S)
]IbX<
/* (non-Javadoc) {"Xn`@Y
* @see com.adt.dao.UserDAO#getUserByPage b~;gj^
Ewjzm,2
(org.flyware.util.page.Page) l ;"v&?
*/ rQ~7BlE
publicList getUserByPage(Page page)throws 9>gxJ7pY
8U,VpuQ:
HibernateException { ^%(HZ'$wC
String querySentence = "FROM user in class (S1c6~
on?<3eED
com.adt.po.User"; v&t~0jX,
Query query = getSession().createQuery YyOPgF] M
h`O"]2
(querySentence); Z05kn{<a8
query.setFirstResult(page.getBeginIndex()) <9zzjgzG{c
.setMaxResults(page.getEveryPage());
*&$J.KM
return query.list(); DONXq]f:,"
} ~)!yl. H
~)5NX
4Po
} 8<BYAHY^
#-76E
p;;4b@
USF9sF0l
3r{3HaN(^'
至此,一个完整的分页程序完成。前台的只需要调用 ckR>ps[ u
L $R"?O7
userManager.listUser(page)即可得到一个Page对象和结果集对象 { +d](+$
+NIq}fZn9
的综合体,而传入的参数page对象则可以由前台传入,如果用 ra87~kj<
8 xfn$
webwork,甚至可以直接在配置文件中指定。 l&rS\TCkp
ITcgpK6k
下面给出一个webwork调用示例: MBy0Ky
java代码: L=`QF'Im
*nb `DR
|'mwr!
/*Created on 2005-6-17*/ O&DkB*-
package com.adt.action.user; iBCZx>![;
6T-h("t
import java.util.List; ]=X6*
E*/E
s98Jh(~
import org.apache.commons.logging.Log; Y
j[M>v
import org.apache.commons.logging.LogFactory; _ ~q!<-Z
import org.flyware.util.page.Page; .3xpDVW^e
&BF97%E2
import com.adt.bo.Result; :bBLP7eyV
import com.adt.service.UserService; JmMB=}
<
import com.opensymphony.xwork.Action; Q]44A+M]
'G] P09`*)
/** NC]]`O2r@
* @author Joa 2o8:[3C5
*/ >"LHr&;m&h
publicclass ListUser implementsAction{ 6I)[6R
0tA~Y26
privatestaticfinal Log logger = LogFactory.getLog ?vA)F)MS
.h({ P#QT
(ListUser.class); Uc>kiWW
!VLk|6mn
private UserService userService; :/rl \woA>
n6A N
private Page page; O}#Ic$38
^?+qNbK
privateList users; |3LD"!rEx
7rIz
/* 7j,-o
* (non-Javadoc) qq
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* W=E+/ZvPt
* @see com.opensymphony.xwork.Action#execute() { XI 0KiE
*/ Lzr&Q(mL
publicString execute()throwsException{ x*`S>_j27=
Result result = userService.listUser(page); }~I(e
page = result.getPage(); |uUGvIsXn
users = result.getContent(); #%Hk-a=>)#
return SUCCESS; =g.R?H8cj5
} o7gYj\
w\V1pu^6@
/** h#hx(5"6
* @return Returns the page. T]er_n
*/ /Pbytu);ds
public Page getPage(){ tLH:'"{zx
return page; m!22tpb
} ye<b`bL2.
GtuA94=!V&
/** P}`|8b1W
* @return Returns the users. ]|JQH
*/ IOfxx>=3
publicList getUsers(){ [Sr^CYP(
return users; ?g{--'L
} A&?8 rc
K20,aWBq;3
/** /gX=79
* @param page [c^!;YBp)
* The page to set. N F$k~r
*/ QJ
i5 H
publicvoid setPage(Page page){ (6}[y\a+
this.page = page; enC/@){~
} -1_WE/Ps
O'Mo/
u1-
/** n%faD
* @param users lr*p\vH
* The users to set. 1;*4yJ2
*/ ;\]&k
publicvoid setUsers(List users){ M2kvj'WWq
this.users = users; 'c&[ kMR
} bIXudE[8zq
<<=.;`(/v
/** aM7e?.rU
* @param userService cyMvjzzRN
* The userService to set. u1}/SlCp
*/ K N Y
publicvoid setUserService(UserService userService){ )_&P:;N
this.userService = userService; ndmsXls
} o5@d1A
} Z bW!c1s{
bcR";cE
adcH3rV
A`B>fI
UF&B7r
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, 0&~JC>S
6%a9%Is!O
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 -Qy@-s $
]x1;uE?1J
么只需要: &lCOhP#
java代码: a1>Tz
sSLVR^
P5JE = &M
<?xml version="1.0"?> bJ"}-s+Dx
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork :[:*kbWN-
kOE\.}~4
1.0//EN" "http://www.opensymphony.com/xwork/xwork- _v#Vf*#
Zt"#'1
1.0.dtd"> SHc?C&^S
f`s.|99Y
<xwork> s/l>P~3=
1gA^Qv~?
<package name="user" extends="webwork- p
uZY4}b_
qyKI.X3n*
interceptors"> o5E5s9n
GI<3L K\
<!-- The default interceptor stack name aD&4C-,1
/;5/7Bvj
--> ^, &'
<default-interceptor-ref /HE{8b7n3F
N79?s)l:K
name="myDefaultWebStack"/> 3Q#Tut
Ez/>3:;
<action name="listUser" i*]$_\yl"
xrZzfg
class="com.adt.action.user.ListUser"> .MS41
E!
<param =o)B1(v@.
Gc=uKQ+\V
name="page.everyPage">10</param> o?g9Grk
<result TFNB%|
Hmx
Y{KB
name="success">/user/user_list.jsp</result> kz"QS.${
</action> h+!@`c>)Y
2M>`W5
</package> ]PlLy:(
NI:3hfs
</xwork> YO9ofT
C"0vMUZ
K8JshFIe
K]'t>:G@
[#SiwhF|
c :2 w(BVi
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 ":_~(?1+
!{?<(6;t
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。 +,_%9v?3
K,o&gY
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 KTE X]
&u4;A[-R
"?G?G'yK>
oO^=%Mc(
yf2P6b\
我写的一个用于分页的类,用了泛型了,hoho tH(g;flO)
cl'wQ1<:
java代码: _l+8[\v
GP(ze-Yp
hvc3n>
Y[}
package com.intokr.util; YCq:]
eGLB,29g
import java.util.List;
fCbd]X
6@x^,SA
/** @e-2]z
* 用于分页的类<br> HF<h-gX
* 可以用于传递查询的结果也可以用于传送查询的参数<br> cAn_:^
* A[`2Mnj
* @version 0.01 )~CNh5z6Y
* @author cheng
(F&o!W
*/ *mz-g7
public class Paginator<E> { ]2c0?f*Y7
privateint count = 0; // 总记录数 N<O<wtXIj
privateint p = 1; // 页编号 iB}*<~`.Eg
privateint num = 20; // 每页的记录数 RBLOc$2
privateList<E> results = null; // 结果 [ut[W9
txiX1o!/L
/** Cw l:
* 结果总数 &Z(6i}f,Gp
*/ t[/APm-k~>
publicint getCount(){ :eH\9$F`x;
return count; D?G'1+RIT~
} -6xh
8 q>
publicvoid setCount(int count){ 92ngSaNC
this.count = count; BZ,{gy7g7X
} Y[s}?Xu]w#
s`|KT&r
/** G1Vn[[%k
* 本结果所在的页码,从1开始 ? ph>:M
* MvTp%d.
* @return Returns the pageNo. x@@bC=iY$
*/ 6 $K@s
publicint getP(){ m:c0S8#:
return p; qJJ},4}
} vwzElZ{C:v
>IipWTVo<
/** lHFk~Qp[
* if(p<=0) p=1 y@<&A~Cl^
* V}ls|B$Y
* @param p t)mc~M9w
*/ ]!uId#OH
publicvoid setP(int p){ }lP`3e
if(p <= 0) !AG {`[b
p = 1; fVJWW):
this.p = p; - LB} =
} 72vp6/;)
L^=G(op*
/** <`u_O!h
* 每页记录数量 i]Bu7Fuu
*/ 6#Rco%07zI
publicint getNum(){ RIDl4c
[
return num; R\-]$\1D
} K'y|_XsBB)
@aP1[( m
/** :%h|i&B
* if(num<1) num=1 X6BOB?
*/ j_h0hm]
publicvoid setNum(int num){ MpTOC&NG%s
if(num < 1) s{*bFA Z1F
num = 1; Z)f?X
this.num = num; {&a6<y#-
} ^b4i9n,t1
D=SjCmG
/** T:" .{h-i
* 获得总页数 211V'|a_>
*/ {w@9\LsU
publicint getPageNum(){ =ui3I_*)
return(count - 1) / num + 1; 9ji`.&#
} =mSu^q(l
MY^o0N
/** ;0`IFtz
* 获得本页的开始编号,为 (p-1)*num+1 >I',%v\?@
*/ biS{.
publicint getStart(){ HBZ6 Pj
return(p - 1) * num + 1; dkeMiLm
} Ro;I%j
mW~*GD~r
/** @<&u;8y-Cn
* @return Returns the results. o$Y#C{wC%
*/ ErgWs Aw-
publicList<E> getResults(){ s LWVgD
return results; ,N
nh$F
} (/E@.z[1
0\,!
public void setResults(List<E> results){ R\<d&+q@
this.results = results; XM#nb$gl
} ]^Xj!01~
=MvB9gx@r
public String toString(){ "xnULQK
StringBuilder buff = new StringBuilder Xkk 8#Y":
E^0a; |B[
(); C{+JrHV%h
buff.append("{"); TF 80WMt
buff.append("count:").append(count); #. 71O#!
buff.append(",p:").append(p); SE(c_ sX
buff.append(",nump:").append(num); Dy:r)\KX
buff.append(",results:").append h6}rOchj
<8YvsJ
(results); ah,"c9YX
buff.append("}"); wk{]eD%
return buff.toString(); <\eRa{ef
} { `xC~B h
[KCR@__
} )[u'LgVN/L
~Orz<%k.
X4+H8],)