Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 **.:)
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 TbMdQbj}
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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 /%5_~Jkr,
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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 E*OG-r
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。 YWSz84d
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分页支持类: &;Ed*OJ
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java代码: TR~|c|B
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package com.javaeye.common.util; WN$R[N
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import java.util.List; %3rTQ:X
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publicclass PaginationSupport { (=`Z0)=
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publicfinalstaticint PAGESIZE = 30; IKGTsA;
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privateint pageSize = PAGESIZE; `bzr_fJ
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privateList items; KS
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privateint totalCount; Q,D0kS P
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privateint[] indexes = newint[0]; J6eJIKK
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privateint startIndex = 0; RzpC1nd
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public PaginationSupport(List items, int u1tq2"D8
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totalCount){ ,.[.SU#V
setPageSize(PAGESIZE); P`p6J8}4
setTotalCount(totalCount); vc )9Re$
setItems(items); Cca6L9%
setStartIndex(0); G4O,^ v;Q
} C/CN
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public PaginationSupport(List items, int qx Wgt(Os
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totalCount, int startIndex){ $4DFgvy$
setPageSize(PAGESIZE); Vu_&~z7h
setTotalCount(totalCount); Z"-ntx#
setItems(items); 4pLQ"&>}80
setStartIndex(startIndex); f( ]R/'o
} mPckf
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public PaginationSupport(List items, int ;0;3BH A
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totalCount, int pageSize, int startIndex){ Yr5iZ~V$
setPageSize(pageSize); {EOn r1
setTotalCount(totalCount); C5>{Q:.`e'
setItems(items); XI]OA7Zis
setStartIndex(startIndex); hN& yc
} 03~+-h&n
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publicList getItems(){ CKx\V+\O
return items; 4Y`! bT`
} EfFj!)fz
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publicvoid setItems(List items){ y=-{Q
this.items = items;
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} |VTWw<{LX
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publicint getPageSize(){ l{nB.m2
return pageSize; )\um"l*\c
} =]!8:I?C<
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publicvoid setPageSize(int pageSize){ $/NGNkl[
this.pageSize = pageSize; C]yvK}
} o~Bk0V=
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publicint getTotalCount(){ 01&*`0?
return totalCount; iSOD&J_
} UVc>i9,0
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publicvoid setTotalCount(int totalCount){ &6`
if(totalCount > 0){ PXOrOK
this.totalCount = totalCount; T^KCB\\<
int count = totalCount / 2.^7?ok
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pageSize; 5JQd)[Im
if(totalCount % pageSize > 0) `K$:r4/[
count++; )3k)2X F
indexes = newint[count]; FI3sLA
for(int i = 0; i < count; i++){ '
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indexes = pageSize * lf?Z{^
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i; 1i5 vW- '4
} j09mI$2y67
}else{ 3{ .9O$
this.totalCount = 0; zi?qK?m
} /IGrp.}
} A>qd2
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publicint[] getIndexes(){ M3hy5j(b
return indexes; 0|WOReskK
} 7yY1dR<Y
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publicvoid setIndexes(int[] indexes){ vS~AxeW/7R
this.indexes = indexes; F7k4C2r
} C\;;9
P Xyyyir{
publicint getStartIndex(){ ?9o#%?6k
return startIndex; 2&^,IIp
} $ka1X&f
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publicvoid setStartIndex(int startIndex){ Iu=pk@*O
if(totalCount <= 0) C! aX45eg
this.startIndex = 0; D]t~S1ycG7
elseif(startIndex >= totalCount) t:?<0yfp&
this.startIndex = indexes B|$\/xO
H @3$1h&YS
[indexes.length - 1]; !1ie:z>s
elseif(startIndex < 0) d+gk q\
this.startIndex = 0; OGSEvfW
else{ UMHuIA:%U
this.startIndex = indexes m
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"cnG/{($*
[startIndex / pageSize]; NTpz)R
} EG Q1li'B
} v:'P"uU;4
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publicint getNextIndex(){ #Z2>TN
int nextIndex = getStartIndex() + DI$mD{
,Ut!u)
pageSize; UDIac;vT
if(nextIndex >= totalCount) {GGO')p
return getStartIndex(); Y\Fuj)
else !Szgph"ul
return nextIndex; Vp- n(Z
} 6E*Zj1KX
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publicint getPreviousIndex(){ ~2, wI<Nz
int previousIndex = getStartIndex() - Og&0Z)%
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pageSize; L<[,7V
if(previousIndex < 0) [)b/uR
return0; h=p-0 Mx .
else ^)eessZ
return previousIndex; N7j]yvE
} FM@W>+
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} 1xFhhncf
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抽象业务类 ,M+h9_&0?
java代码: S7\|/h:4
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/** >mGGJvTx
* Created on 2005-7-12 `Tm8TZd66
*/ tyGnG0GK
package com.javaeye.common.business; ^{6UAT~!R
l*m]2"n]
import java.io.Serializable; sKE*AGFLd
import java.util.List; hj#+8=
H)?" 8 s
import org.hibernate.Criteria; ]0/~6f
import org.hibernate.HibernateException; +Qb2LR
import org.hibernate.Session; ]UpHD.Of[t
import org.hibernate.criterion.DetachedCriteria; 4n.i<K8K[
import org.hibernate.criterion.Projections; lHj7O&+
import 9X^-)G>
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org.springframework.orm.hibernate3.HibernateCallback; |)>GeE
import ><Mbea=U+
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org.springframework.orm.hibernate3.support.HibernateDaoS )}zA,FOA*
BZ'y}Zu*
upport; #L+s%OJ`
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import com.javaeye.common.util.PaginationSupport; ,XF6Xsg2
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public abstract class AbstractManager extends X\^3,k."
e[py J.
HibernateDaoSupport { 5qODS_Eq
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privateboolean cacheQueries = false; ve_4@J)
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privateString queryCacheRegion; ?M1 QJ
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publicvoid setCacheQueries(boolean =tvm=
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cacheQueries){ []]LyWk
this.cacheQueries = cacheQueries; [wpt[zG
} , K"2tb
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publicvoid setQueryCacheRegion(String \)6?u_(u
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queryCacheRegion){ Wf&G9Be?8
this.queryCacheRegion = fb S.
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queryCacheRegion; N[?4yV2s
} B )3SiU
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publicvoid save(finalObject entity){ 4VL!U?dk
getHibernateTemplate().save(entity); Se]t;7j
} a!6OE"?QQ
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publicvoid persist(finalObject entity){ <pa];k(IQL
getHibernateTemplate().save(entity); *^$N$t/2
} e715)_HD
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publicvoid update(finalObject entity){ f~(^|~ZT
getHibernateTemplate().update(entity); !nD[hI8P
} oCru 5F
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publicvoid delete(finalObject entity){ (^OC%pc
getHibernateTemplate().delete(entity); 6T'43h. :
} Y&!McM!Jw
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publicObject load(finalClass entity, F@*r%[S/
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finalSerializable id){ 0BU:(o&
return getHibernateTemplate().load h"%,eW|^
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(entity, id); XajY'+DIsz
} Jv$2wH
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publicObject get(finalClass entity, cF>;f(X
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finalSerializable id){ ovRCF(Og,
return getHibernateTemplate().get [}g5Z=l
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(entity, id); 5<'Jd3N{&
} "i5AAP?_]{
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publicList findAll(finalClass entity){ orN2(:Ct7
return getHibernateTemplate().find("from 'bqf?3W
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" + entity.getName()); 7!d<>_oH
} Mh@ylp+q
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publicList findByNamedQuery(finalString %li{VDb
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namedQuery){ *g_>eNpXD
return getHibernateTemplate gM/_:+bT>P
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().findByNamedQuery(namedQuery); 7JK 'vT
} !c;p4B)
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publicList findByNamedQuery(finalString query, PyJblW
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finalObject parameter){ m`w6wz
return getHibernateTemplate \VzQ1B>k
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().findByNamedQuery(query, parameter); :<|fZa4!"
} Wh&Z *J
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publicList findByNamedQuery(finalString query, m3ZOq
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finalObject[] parameters){ f#JF5>o
return getHibernateTemplate !{- 3:N7
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().findByNamedQuery(query, parameters); .6]cu{K(
} W;j)ux7jMY
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publicList find(finalString query){ C]@B~X1H^
return getHibernateTemplate().find PDiorW}]k
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(query); ]7ZC>.t
} Ki6BPi^
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publicList find(finalString query, finalObject 8&AorYw[
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parameter){ D.JVEKLkU
return getHibernateTemplate().find Jrrk$0H^~
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(query, parameter); HCCp<2D"C
} h!3Z%M
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public PaginationSupport findPageByCriteria V'#u_`x"D)
}C1}T}U
(final DetachedCriteria detachedCriteria){ 9d|7#)a;
return findPageByCriteria Y2~{q Y
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); =|^W]2W$
} Y\2>y"8>$x
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public PaginationSupport findPageByCriteria MZ[g|o!)v
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(final DetachedCriteria detachedCriteria, finalint >~r@*gml
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startIndex){ n_gB#L$
return findPageByCriteria t$Ji{t-
Z%d4V<fn
(detachedCriteria, PaginationSupport.PAGESIZE, ]nGA1 S{
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startIndex); DxG'/5jQ[
} Y\F H4}\S
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public PaginationSupport findPageByCriteria Y'":OW#oN
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(final DetachedCriteria detachedCriteria, finalint IWd*"\L
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pageSize, M0\[hps~X
finalint startIndex){ S5p\J!k\B
return(PaginationSupport) =hb87g.
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getHibernateTemplate().execute(new HibernateCallback(){ %zVv3p:
publicObject doInHibernate D($UbT-v
*m/u 3.\
(Session session)throws HibernateException { PhdL@Mr
Criteria criteria = BAed [
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detachedCriteria.getExecutableCriteria(session); ^W*)3;5
int totalCount = 5.;$9~d
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((Integer) criteria.setProjection(Projections.rowCount JG$J,!.\
{x$#5PW
()).uniqueResult()).intValue(); 6XqO'G
criteria.setProjection JH,+F
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(null); b .@dUuKz-
List items = &~i
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criteria.setFirstResult(startIndex).setMaxResults kKO]q#9sO
61 |xv_/
(pageSize).list(); B*Xh$R
PaginationSupport ps = QR8Q10
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new PaginationSupport(items, totalCount, pageSize, qa#F}aGd
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startIndex); x/v+7Pt_
return ps; 2?&ptN)`N
} KL{uhb0f
}, true); &WS%sE{p_
} =i<(hgD
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public List findAllByCriteria(final s47"JKf"
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DetachedCriteria detachedCriteria){ l^Z~^.{y
return(List) getHibernateTemplate $RO=r90o
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().execute(new HibernateCallback(){ )f|6=x4
publicObject doInHibernate I>|?B(F
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(Session session)throws HibernateException { 81C?U5
Criteria criteria = ,]'!2?
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detachedCriteria.getExecutableCriteria(session); *2hzReM
return criteria.list(); Cl=ExpX/O
} ~Y[b
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}, true); )`0 j\
} kv2:rmv
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public int getCountByCriteria(final R'U(]&e.j
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DetachedCriteria detachedCriteria){ m\Nc}P_"p
Integer count = (Integer) =uEhxsj)S
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getHibernateTemplate().execute(new HibernateCallback(){ /GNYv*
publicObject doInHibernate T9yW# .
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(Session session)throws HibernateException { G3n7x?4m
Criteria criteria = s"Wdbw(O '
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detachedCriteria.getExecutableCriteria(session); F[Up
return m5*RB1
^%.<(:k[L
criteria.setProjection(Projections.rowCount \Ld7fP
chbs9y0
()).uniqueResult(); X+jSB,
} Vy VC#AK,
}, true); /PlsF
return count.intValue(); xR3A4m
} "a7d`l:
} :7zI!edu
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用户在web层构造查询条件detachedCriteria,和可选的 fq'Of
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 C_/oORvK
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PaginationSupport的实例ps。 A
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ps.getItems()得到已分页好的结果集 QO%K`}Q}
ps.getIndexes()得到分页索引的数组 h9mR+ng*oD
ps.getTotalCount()得到总结果数 V8/o@I{U[
ps.getStartIndex()当前分页索引 nEYJ?_55
ps.getNextIndex()下一页索引 bC|~N0b
ps.getPreviousIndex()上一页索引 ?CC6/bE-{
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 Yv)/DsSyL
Et(prmH
,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 P:+:Cm<
[iD!!{6+
一下代码重构了。 jn'8F$GU
z&8#1'
我把原本我的做法也提供出来供大家讨论吧: ?.H*!u+9>
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首先,为了实现分页查询,我封装了一个Page类: 53c6dl
java代码: gQ[4{+DSf
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/*Created on 2005-4-14*/ Yp8$0KK
package org.flyware.util.page; IM+PjYJ
R!=XMV3$PH
/** %k~=iDk@
* @author Joa iDA`pemmi&
* \[BnAgsF
*/ ?w+T_EH
publicclass Page { Hs9uDGWp
R B!g,u
/** imply if the page has previous page */ Gu-Sv!4p
privateboolean hasPrePage; NTC,Vr\A
/i<g>*82
/** imply if the page has next page */ [3s~Z8
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privateboolean hasNextPage; nz(OHh!}u
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/** the number of every page */ A8?>V%b[Y
privateint everyPage;
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/** the total page number */ 8[k-8h|
privateint totalPage; Gs%kqD{=
iR9iI!+;N
/** the number of current page */ @RC_Ie=#)
privateint currentPage; A U](pXK;
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/** the begin index of the records by the current lxeolDl
t?s1@}G^
query */ A[oRi}=
privateint beginIndex; n1QO/1}
:
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/** The default constructor */ CAX U
#
public Page(){ ("{'],>
*(rq AB0~
} SF6n06UZu
z)ydQw>
/** construct the page by everyPage "}n]0 >J
* @param everyPage Vrnx#j-U
* */ 0wx`y$~R
public Page(int everyPage){ 4x:fOhtP
this.everyPage = everyPage; g
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} ;y"DEFs,u
ykZ)`E]P`
/** The whole constructor */ 'F@'4[uda
public Page(boolean hasPrePage, boolean hasNextPage, A9"ho}<
6 R!0v8
uB%`Bx'OW
int everyPage, int totalPage, gw H6r3=y(
int currentPage, int beginIndex){ =0Nd\
this.hasPrePage = hasPrePage; 'b-}KDP
this.hasNextPage = hasNextPage; X0m\
this.everyPage = everyPage; EfOJ%Xr[,l
this.totalPage = totalPage; 1&dWt_\
this.currentPage = currentPage; m^wYRA.
this.beginIndex = beginIndex; @=$;^}JS|
} VL\6U05Z
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/** BM3nZ<%3
* @return z2r{AQ.&
* Returns the beginIndex. kWgxswl7H
*/ [j5L}e!T
publicint getBeginIndex(){ Uu
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return beginIndex; :wIbKs.r
} mF
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;&iQNXL
/** [g<JP~4]
* @param beginIndex /vBp Rm
* The beginIndex to set. +Ta7b)
*/ 6%)dsTAB
publicvoid setBeginIndex(int beginIndex){ !4|7U\;
this.beginIndex = beginIndex; HH>]"mv
} IkD\YPL;
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/** [z?<'Tj
* @return 5RqkAC
* Returns the currentPage. V97Eb>@
*/ SA'
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publicint getCurrentPage(){ hse$M\5
return currentPage; !?]NMf_
} E}~GX G
*/6PkNq
/** vrH/Z.WD
* @param currentPage :Vv=p*~
* The currentPage to set. 7dAa~!/(
*/ &QvWT+]c'0
publicvoid setCurrentPage(int currentPage){ ^!=+$@<
this.currentPage = currentPage; PQ1\b-I
} .Zo8KwkFY
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/** @;pTQ
5
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* @return S/8xo@vct]
* Returns the everyPage. d<xBI,g
*/ xmbkn}@A
publicint getEveryPage(){ Tc{r}y[)
return everyPage; }y'KS:Jb
} @zE_fL
CB|Z~_Bm
/** gVA$P
* @param everyPage KN5.2pp
* The everyPage to set. {eS!cZJ
*/ oveW )~4
publicvoid setEveryPage(int everyPage){ 7GpSWM6
this.everyPage = everyPage; ^lf)9 `^U
} s2q#D.f
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/** +[:}<^p?cG
* @return ZVViu4]?y
* Returns the hasNextPage. ^*RmT
*/ {um~]
publicboolean getHasNextPage(){ hmQD-E{Ab
return hasNextPage; _ u/N#*D
} *ZAue.
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/** ?NJ\l5'
* @param hasNextPage &vo]l~.
* The hasNextPage to set. ;4%^4<+3
*/ Sa6}xe."M,
publicvoid setHasNextPage(boolean hasNextPage){ 7h,SX]4Q
this.hasNextPage = hasNextPage; %*zgN[/w
} gFJd8#6t
/&a[D2
/** VcA87*pel
* @return YaDr6)
* Returns the hasPrePage. ^~?VD
*/ B]#0]-ua
publicboolean getHasPrePage(){ cW%F%:b
return hasPrePage; 0OP6VZ\
} t\S}eoc
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/** [.;VCk)0x
* @param hasPrePage ~}(}:#>T
* The hasPrePage to set. M{Wla7
*/ nTyKZ(#u
publicvoid setHasPrePage(boolean hasPrePage){ Od)]FvO
this.hasPrePage = hasPrePage; )Yy`$`
} ohOze\T)=
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/** Syo1Dq6z.
* @return Returns the totalPage. Bzw~OB{!=J
* xbSix:R=Z
*/ 5e6 f)[}
publicint getTotalPage(){ skf7Si0z
return totalPage; &dH/V-te
} %TP0i#J
<T,vIXwu+
/** kO+Y5z6=
* @param totalPage 8 W79
* The totalPage to set. zvL;.U
*/ ]`b/_LJN$F
publicvoid setTotalPage(int totalPage){ M1-n
this.totalPage = totalPage; vg5i+ry<
} @/g%l1$`
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} P?\ IlziCB
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nZ0-
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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 AQw1,tGV
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个PageUtil,负责对Page对象进行构造: YAYPof~A$l
java代码: z1{kZk
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/*Created on 2005-4-14*/ ]6bh #N;.
package org.flyware.util.page; +mIO*UQi
v[E*K@6f
import org.apache.commons.logging.Log; L'iENZI$
import org.apache.commons.logging.LogFactory; tURjIt,I
j'R{llZW
/** kI<;rP1S|
* @author Joa n6Je5fE
* E_[|ZrIO&*
*/ dkVF
publicclass PageUtil { dDK4I3a
#N.W8mq
privatestaticfinal Log logger = LogFactory.getLog |4^us|XY
UzTFT:\
(PageUtil.class); 2~h! ouleY
fkbHfBp[(A
/** M_lQ^7/
* Use the origin page to create a new page &mXJL3iN
* @param page z~\a]MB
* @param totalRecords A)/8j2
* @return b{%p
*/ .fY1?$*6c
publicstatic Page createPage(Page page, int [#hpWNez(>
"%ou'\}
totalRecords){ !W4A9Th
return createPage(page.getEveryPage(), O9?t,1
A/ZZ[B-
page.getCurrentPage(), totalRecords); `K5Lp>=R
} a~ sU
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/** 7)SG#|v[$
* the basic page utils not including exception ]/g&y5RG
wFI2(cQ
handler }tJRBb
* @param everyPage 5tfD*j n
* @param currentPage oM\b>*
* @param totalRecords Xo[j*<=0
* @return page DLggR3K_\
*/ .
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publicstatic Page createPage(int everyPage, int q$RJ3{Sf
6Y9F U
currentPage, int totalRecords){ ,\8F27
everyPage = getEveryPage(everyPage); gCfAy=-,V
currentPage = getCurrentPage(currentPage); m.!n|_}]
int beginIndex = getBeginIndex(everyPage, mUSrC U_}
9j<qi\SSI
currentPage); r&!Ebe-
int totalPage = getTotalPage(everyPage, %:Mi6sR|
6bPoC$<Z
totalRecords); m03D+@F
boolean hasNextPage = hasNextPage(currentPage, JV_VF'
bvn%E
H
totalPage); X?'Sh XI
boolean hasPrePage = hasPrePage(currentPage); "}ibH{$lM
B}S!l>.z
returnnew Page(hasPrePage, hasNextPage, K!~j}z*
everyPage, totalPage, }\
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currentPage, )bqSM&SO
ufl[sj%^|
beginIndex); 1'Sr0
oEd3
} ?|,dHqh{nM
(dvsGYT|.
privatestaticint getEveryPage(int everyPage){ w8veh[%3n
return everyPage == 0 ? 10 : everyPage; H#/ #yVw
} ={g.Fn(_
t"# .I?S0
privatestaticint getCurrentPage(int currentPage){ <9f;\+zA
return currentPage == 0 ? 1 : currentPage; [Ey[A|g
} a9LK}xc={
O2;iY_P7lV
privatestaticint getBeginIndex(int everyPage, int _EHz>DJ9
omdoH?
currentPage){ \G4L+Q/13
return(currentPage - 1) * everyPage; A$ 2 AYQ
} 0nOkQVMk>
Z2P DT
privatestaticint getTotalPage(int everyPage, int ;@ <E
&BOq%*+
totalRecords){ K<3,=gL9[
int totalPage = 0; iEx
sGn]2
Sjb[v
if(totalRecords % everyPage == 0) vC#_PI
totalPage = totalRecords / everyPage; fl@=h[g#t
else x)}.@\&%
totalPage = totalRecords / everyPage + 1 ; &JUHm_wd&S
fI<|]c}P&J
return totalPage; <b.O^_zQF
} yj$a0Rgkv
2eC`^
privatestaticboolean hasPrePage(int currentPage){ t@(:S6d
return currentPage == 1 ? false : true; t_xO-fT)
} S"=y>.#
L/Tsq=
privatestaticboolean hasNextPage(int currentPage, 3bsuE^,.@
b;;mhu[D
int totalPage){ 6Dl]d%.
return currentPage == totalPage || totalPage == EN2H[i+,
pZxuV(QP`
0 ? false : true; simD<&p
} !&(^R<-id
!#[B#DZc(
rd_!'pG
} 1
lZRi-P
;9Sb/
;6)Onwx
2#jBh
MA`.&MA.
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 xcHuH-}
aw\0\'}
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 L$zB^lSM
1XppC[))
做法如下: !+EE*-c1c
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 E\Qm09Dj`<
qrr[QEFW
的信息,和一个结果集List: ITssBB9
java代码: w. c]
90Sp(
0FAe5
BE7
/*Created on 2005-6-13*/ 9 $&$Fe
package com.adt.bo; -bP_jIZF;g
uN;]Fv@Z
import java.util.List; Ss~yy0
k>.n[`>$6|
import org.flyware.util.page.Page; $n#NUPzG+
EP'I
/** <$>Jsv
* @author Joa Bj`ZH~T
*/ F1A7l"X]
publicclass Result { CT0 ~
a%YohfsY?U
private Page page; lKSd]:3Xm
aj`_*T"A
private List content; z)_h"y?H{%
/^pPT6
/** A.5`+
* The default constructor i-FsA
*/ b#[EkI 0@
public Result(){ /idrbc
super(); 0!tw)HR%
} ~Gj%z+<
!;, Dlq-}
/** M5Q7izM
* The constructor using fields d:!A`sk7
* oMeIXb)z
* @param page Oz1S*<]=,~
* @param content FzzV%
*/ gp(: o$
public Result(Page page, List content){ f&2f8@
this.page = page; eqQ=HT7J
this.content = content; *=b36M
} |aX1PC)o_
WNO!6*+
/** I&JjyR
* @return Returns the content. &UxI62[k
*/ mmvo
>F"
publicList getContent(){ ,!>1A;~wT
return content; cCBYM
} G$oi>zt3
mx=2lL`
/** xgq
`l#
* @return Returns the page. n6C]JWG\/U
*/ x='T`*HD
public Page getPage(){ vrX@T?>
return page; [X^Oxs
} ZW@%>_JR]
z@Uf@~+U
/** iOrpr,@
* @param content `Kb"`}`_vm
* The content to set. b^^ .$Gu
*/ Q:^.Qs"IK
public void setContent(List content){ jnIf(a
this.content = content; %f1>cO9[
} .H#<yPty
UAEu.AT
/** UlQS]f~
* @param page d1BE;9*/7
* The page to set. ^_ST#fFS
*/ &xLCq&j1
publicvoid setPage(Page page){ Op5S'
this.page = page; 13aj fH
} LQz6op}R
} fWs @ZCt
LK:J kjp^
C
)J@`E
2>*b.$g
srQ]TYH ,
2. 编写业务逻辑接口,并实现它(UserManager, M37GQvo
Nv5)A=6#AA
UserManagerImpl) /8Ru O
java代码: 0BrAgv"3a_
$_f"NE}
7'zXf)!
/*Created on 2005-7-15*/ ^\Epz*cL
package com.adt.service; e1/{bX5
`'G1"CX
import net.sf.hibernate.HibernateException; 1"wZ [.
?rxq//S2
import org.flyware.util.page.Page; UUR+PfY
u3vM !
import com.adt.bo.Result; 9p4=iXfR
Xj5oHHwn
/** %$[#/H7=W
* @author Joa .D{He9
*/ *W-:]t3CR
publicinterface UserManager { brEA-xNWQ
u"gtv
public Result listUser(Page page)throws Xkp?)x3~X
Sp/<%+2(
HibernateException; h>"j!|#!s
2Y~nU(
} EE5mVC&
:r4o:@N'
-]Y@_T.C
v2jpao<K
2(AuhZ>
java代码: XiO~^=J
*2>kic
aH
W9!K~g_
/*Created on 2005-7-15*/ {RC&Ub>
package com.adt.service.impl; VRB!u420
K_ Od u^
import java.util.List; v3b+Ddp
:Z&<5
import net.sf.hibernate.HibernateException; CB^.N>'
xi[\2g+
import org.flyware.util.page.Page; )F_nK f"a
import org.flyware.util.page.PageUtil; -pW*6??+?
Q<>b3X>O
import com.adt.bo.Result; 5tl($j
import com.adt.dao.UserDAO; Q 6n!u;
import com.adt.exception.ObjectNotFoundException; 3I G<Ot9
import com.adt.service.UserManager; "A]#KTP
yJ4ZB/ZQ
/** #QNa|
f#=
* @author Joa y.$Ae1a=
*/ 8/k"A-m
publicclass UserManagerImpl implements UserManager { SS6K7
k`w/
private UserDAO userDAO; G@zJf)u}
fS$;~@p
/** :i>If:>g
* @param userDAO The userDAO to set. hgK
4;R
*/ =Q*x=}NH
publicvoid setUserDAO(UserDAO userDAO){ s#H_QOE
this.userDAO = userDAO; N6HeZB":
} SQDfDrYP
$wC'qV
*
/* (non-Javadoc) FfNUFx2N
* @see com.adt.service.UserManager#listUser _tRRIW"Vx"
nJ}@9v F/
(org.flyware.util.page.Page) H[RX~Xk2E
*/ 0X:$ASocU
public Result listUser(Page page)throws Y @Ur}
e}+Zj'5
HibernateException, ObjectNotFoundException { _FxeZ4\
int totalRecords = userDAO.getUserCount(); @{"?fqo
if(totalRecords == 0) MK(~
throw new ObjectNotFoundException s:3b. *t<
:$*@S=8 O
("userNotExist");
ejc>
page = PageUtil.createPage(page, totalRecords); zGNmc7
List users = userDAO.getUserByPage(page); IGOEqUw*
returnnew Result(page, users); 82iFk`)T
} sYbmL`{
SBI*[
} !Df>Q5~g
.C` YO2,
zpjE_|
@H8DGeM
(K_{a+$[
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 V8Ri2&|3
c \;_jg
询,接下来编写UserDAO的代码: 1obajN
3. UserDAO 和 UserDAOImpl: ~=Q^]y,
java代码: Sc]G7_
U;j\FE^+>
~+C)0Yn
/*Created on 2005-7-15*/ XZ@|(_Z
package com.adt.dao; GT<!e]=6
k{H7+;_
import java.util.List; z'7XGO'Lo
O7p=N8 V
import org.flyware.util.page.Page; L5'?.9]
gD2P)7:
import net.sf.hibernate.HibernateException; VeSQq
mVFo2^%v
/** BOWBD@y
* @author Joa u 7:Iv
*/ A"z9t#dv@
publicinterface UserDAO extends BaseDAO { 74 &q2g{
+D2I~hC0'
publicList getUserByName(String name)throws W>5[_d
_M+7)[xj=
HibernateException; s94*uZ(C/
[r!f&R
publicint getUserCount()throws HibernateException; ia(`3r
:a^/&LbLm
publicList getUserByPage(Page page)throws ]6F\a= J
f>bL
}L
HibernateException; A'.=SA2.Y
H~^)^6)^T
} '/)qI.
f!{@{\
Ch\__t*v!
":f]egq
-
S+#|j
java代码: Q'qX`K+@`
AVm+
1
XDHi4i47`o
/*Created on 2005-7-15*/ 050,S`%<g8
package com.adt.dao.impl; tHAe
L^r & .N\
import java.util.List; }8POm#
NJ]3qH
import org.flyware.util.page.Page; a9UXg<4
Vn_~ |-Wt
import net.sf.hibernate.HibernateException; Kk*8
import net.sf.hibernate.Query; l*6Zh"o:
8NiR3*1
import com.adt.dao.UserDAO; uovv">Uw
[h8s0
/** %~y>9K
* @author Joa /M+Du,
*/ +V Nk#Z i
public class UserDAOImpl extends BaseDAOHibernateImpl =~k
c7f{
zgH(/@P
implements UserDAO { U`lK'..
:PtZKt;~X
/* (non-Javadoc) ~USt&?
* @see com.adt.dao.UserDAO#getUserByName 1Qu@pb^
|JP19KFx'B
(java.lang.String) 9Msy=qvYG
*/ z~ywFk}KGd
publicList getUserByName(String name)throws R|v'+bv
H]pI$t3~
HibernateException { yIrJaS-
String querySentence = "FROM user in class XbqMWQN*
]8}51y8
com.adt.po.User WHERE user.name=:name"; o<G#%9j
Query query = getSession().createQuery AYgXqmH~+
u*TC8!n
(querySentence); B\v+C!/f|
query.setParameter("name", name);
B6Eu."T
return query.list(); 993f6
} :aK?Dt Z
tq}45{FH3
/* (non-Javadoc) jn:_2g[
* @see com.adt.dao.UserDAO#getUserCount() |K"Q>V2y
*/ ZZ7qSyBs?
publicint getUserCount()throws HibernateException { M
`^[Y2 c
int count = 0; i'7+
?YL
String querySentence = "SELECT count(*) FROM u '7h(1@
LP=j/qf|
user in class com.adt.po.User"; Ps74SoD-
Query query = getSession().createQuery BBRL_6
Jjm#ofv
(querySentence); ;4[[T%&v
count = ((Integer)query.iterate().next }!AS?
5,pNqXRp
()).intValue(); l6y}>]
return count; W3:Fw6v
} nuXL{tg6
0]kKF<s
/* (non-Javadoc) sVK?sBs]
* @see com.adt.dao.UserDAO#getUserByPage +a3E=GJ
>
[J.
(org.flyware.util.page.Page) qyv=ot0"~F
*/ dF\#:[B
publicList getUserByPage(Page page)throws V`1,s~"q
pL5cw=
HibernateException { 1^4:l!0D
String querySentence = "FROM user in class ,VHqZ'6
@kqxN\DE
com.adt.po.User"; ?9kC[4G
Query query = getSession().createQuery :-B+W9'5
d=PX}o^
(querySentence); N+=|WeZ
query.setFirstResult(page.getBeginIndex()) 80Dn!9j*
.setMaxResults(page.getEveryPage()); RqtBz3v
return query.list(); eHy UY&N/
} BVw2skOT
RZzHlZ
} ujZ`T0
bI55G#1G
h6Z:+
`8ac;b
s*ZE`/SM3
至此,一个完整的分页程序完成。前台的只需要调用 } #rTUX
Q$c6l[(g
userManager.listUser(page)即可得到一个Page对象和结果集对象 )1uiY
f&k
e@Lxduq
的综合体,而传入的参数page对象则可以由前台传入,如果用 FfdB%
6
Rl[M+Q
webwork,甚至可以直接在配置文件中指定。 [OW <<6
Do/R.Mgy*
下面给出一个webwork调用示例: YV<y-,Io
java代码: ,U z8 _r
#$I@V4O;#
HOR8Jwf:
/*Created on 2005-6-17*/ 9{*{Ba
package com.adt.action.user; P.'.KZJ:WD
@up,5`
import java.util.List; %.Ma_4o
Z
rm8Ys61\=
import org.apache.commons.logging.Log; +;?mg(:
import org.apache.commons.logging.LogFactory; @-'a{hBR
import org.flyware.util.page.Page; SM2Lbfp!u
mG jB{Q+
import com.adt.bo.Result; tWIs
|n
import com.adt.service.UserService; 9 {&g.+
import com.opensymphony.xwork.Action; HIXAA?_eh=
JWixY/
/** ^#HaH
* @author Joa 7k(}U_v
*/ !6KX^j-
publicclass ListUser implementsAction{ Y%XF64)6
*siX:?l
privatestaticfinal Log logger = LogFactory.getLog ~U0%}Bbh
|O{N_-];.
(ListUser.class); &-3e3)
K(EJ`2]:r
private UserService userService; h2ROQKL"B
b=,BLe\
private Page page; C/e.BXA
gV2vwe
privateList users; J~m$7T3Af
b/M/)o!C
/* /4G1,T_,
* (non-Javadoc) Ti%MOYNCv
* D&G6^ME
* @see com.opensymphony.xwork.Action#execute() E^1yU
*/ }QFL
publicString execute()throwsException{ YThVG0I =
Result result = userService.listUser(page); srVWN:uuH
page = result.getPage(); sbW+vc
users = result.getContent(); 2d D"^z{
return SUCCESS; o,*m,Qc
} uUI#^ A
Qr.{_M
/** @dWA1tM
* @return Returns the page. DYf QlA
*/ :_8K8Sa
public Page getPage(){ g3:@90Ba
return page; GV0\+A"vD
} AxH;psj
6g|,]{
/** kE&R;T`Gb%
* @return Returns the users. <=4$.2ym
*/ p<mL%3s0
publicList getUsers(){ :Y99L)+=/
return users; &}"kF\
} $*C
}iJsF
d@Z DIy
/** h4hAzFQ.s
* @param page T3wTMbZ!VK
* The page to set. :zHSy&i`
*/ q" VmuQ
publicvoid setPage(Page page){ yKML{N1D
this.page = page; 8<VDp Y
} !db=Iz5)
@]Jq28
/** q8{Bx03m6
* @param users imM!Me 0TE
* The users to set. Z",0 $Gxu
*/ 1=5"j]0hY
publicvoid setUsers(List users){ O*u
this.users = users; %J*1F
} 2*cNd}qr
xA3_W
/** 8{>|%M
* @param userService T9yI%;D
* The userService to set. PaTOlHr
*/ $DDO9
publicvoid setUserService(UserService userService){ 8-;.Ejz!\A
this.userService = userService; `oxBIn*BD
} f#s 6 'g
} )z7CT|h7S
`wi+/^);
1uo-?k
VzT*^PFBg
(Y~/9a4X
上面的代码似乎看不出什么地方设置了page的相关初值,事实上, 59.$;Ip;g
]3v)3Wp
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 u>'0Xo9R
+3))G
么只需要: ]xS%Er
java代码: `{#""I^_
AF:_&gF
L'wR$
<?xml version="1.0"?> =c6d$
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork
^tTM
7
}9ulHiR
1.0//EN" "http://www.opensymphony.com/xwork/xwork- ) 8xbc&M
c]*yo
1.0.dtd"> R~=c1bpdq
z(A60b}
<xwork> qjRbsD>
g0 Q,]\~
<package name="user" extends="webwork- Ic3a\FTr\
^iH[
22b4
interceptors"> K"l~bFCZ8
Aw7N'0K9UN
<!-- The default interceptor stack name $?ss5:
S
?8753{wk
--> %g?M?D8Ud3
<default-interceptor-ref v}!lx)#
%RW*gUvc]
name="myDefaultWebStack"/> (\qf>l+*
5B~]%_gZr
<action name="listUser" ^qL<=UC.
'A[PUSEE
class="com.adt.action.user.ListUser"> +P))*0(c_
<param }X9&!A8z
P*k n}:
name="page.everyPage">10</param> 3uw3[
SR1
<result N!7?D'y
l(1.Ll
name="success">/user/user_list.jsp</result> ` 0@m,
</action> 3X Y"s"
UK6x]tE
</package> _E9[4%f
;-JF1p 7;
</xwork> b0}dy\dnQ
d\-*Fmp(S
bM'F8Fi
-medD G
$\m:}\%p
h8WM4
PK
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 X!V#:2JY
GYtgw9 "Y
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。 odL*_<Z
HMD\)vMK6
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 iklZ[G%A0
2(uh7#Q
Q)E3)),
*QN,wBQ
XnYX@p
我写的一个用于分页的类,用了泛型了,hoho /QB;0PrE
LmY[{.'tX
java代码: Swf%WuDj
(<.\v@7HC
papMC"<g$
package com.intokr.util; r7R39#
}x|q*E\
import java.util.List; U
`lp56
BW)@.!C
/** X+{brvM<
* 用于分页的类<br> C6g p}%
* 可以用于传递查询的结果也可以用于传送查询的参数<br> (-J'x%2)
* aY4v'[
* @version 0.01 X#by Dg
* @author cheng |"}7)[BW}
*/ 8@doKOA~T
public class Paginator<E> { I@qGDKz;
privateint count = 0; // 总记录数 jp"Q[gR##
privateint p = 1; // 页编号 M:.+^.h
privateint num = 20; // 每页的记录数 ]*MVC/R,
privateList<E> results = null; // 结果 O,7S1
le_aIbB"P
/** bp" @p:
* 结果总数 'PrBa[%
*/ GfSD%"
publicint getCount(){ h}tC+_"D
return count; {ZdF6~+H(!
} W NeBthq6
*oLDy1<
publicvoid setCount(int count){ G'Wp)W;])\
this.count = count; ]>Dbta.27
} Xn~\Vb
rosD)]I7
/** 'pUJREb
* 本结果所在的页码,从1开始 8mOGEx
* Z0M,YSn z
* @return Returns the pageNo. #""T>+
*/ d=D#cs;\
publicint getP(){ +tt!xfy
return p; : &nF>
} n2_;:=
#%%!r$UL
/** ePq (.o
* if(p<=0) p=1 t>a D;|Y
* HNc/p4z
* @param p LB({,0mcX
*/ .*n*eeD,
publicvoid setP(int p){ 2rC&
if(p <= 0) E 6MeM'sx
p = 1; J8@.qC'!
this.p = p; I5QtPqB>
} sZ7,7E|_
XgXXBKf$
/** Z0v?3v}9^
* 每页记录数量 ]1zud
*/ SXe1Q8;
publicint getNum(){ __+8wC
return num; ~K5A$s2
} QrFKjmD<
Y^DGnx("m
/** 3.P7GbN
* if(num<1) num=1 Xf"<
>M
*/ g'w"U9tjO
publicvoid setNum(int num){ raSga'uT;
if(num < 1) +84
p/B#
num = 1; } 7:T?
`V:
this.num = num; j[mII5e7g
} |c2sJy j*
x)Zm5&"Gg
/** p{v*/<.;
* 获得总页数 Zl'/Mxg
*/ h-O;5.m-P
publicint getPageNum(){ _iDVd2X"H
return(count - 1) / num + 1; R
i,_x
} (GGosXU-v
(~bx %
/** zN;P_@U
* 获得本页的开始编号,为 (p-1)*num+1 !;vv-v,LQ
*/ 3 G<4rH]
publicint getStart(){ qQ3pe:n?
return(p - 1) * num + 1; 2"shB(:z>
} QBi]gT@&g
}CZw'fhVWO
/**
JC9$"0d7
* @return Returns the results. bZAL~z+ V
*/ IsJx5GO
publicList<E> getResults(){ PJ?C[+&
return results; (C
uM*-
} XHdhSFpm
f[R~oc5P0
public void setResults(List<E> results){ bWlYQ
this.results = results; _!vy|,w@e
} @^ti*`
f52P1V]
public String toString(){ f9},d1k
StringBuilder buff = new StringBuilder OAiv3"p
JKrS;J^97v
(); ~b
X~_\
buff.append("{"); .}Xf<G&
buff.append("count:").append(count); yH43Yo#Rk
buff.append(",p:").append(p); @TXLg2
buff.append(",nump:").append(num); Ac*J;fI
buff.append(",results:").append \/\w|j
3HuGb^SNg
(results); 6rD]6#D
buff.append("}"); =O8>[u;
return buff.toString(); }(XKy!G6
} 8HZ+r/j
x H=15JY1W
} d:^B2~j
H[OgnnM
IoK/ 2Gp