Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 nECf2>Yp v
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 _qNLy/AY
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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 Y}z?I%zL
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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 *dgNpJ 9
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分页支持类: 4u7>NQUDu
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java代码: ?saVk7Z[|5
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package com.javaeye.common.util; =%G[vm/-)
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import java.util.List; Vtk|WV?>P+
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publicclass PaginationSupport { ' "
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publicfinalstaticint PAGESIZE = 30; vH8%a8V
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privateint pageSize = PAGESIZE; Rj=Om
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privateList items; (LPD
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privateint totalCount; F\72^,0
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privateint[] indexes = newint[0]; F'*4:WD7
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privateint startIndex = 0; {mGWMv
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public PaginationSupport(List items, int 4tTJE<y
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totalCount){ NQ=YTRU
setPageSize(PAGESIZE); Dw,f~D$+ic
setTotalCount(totalCount); kJFHUR
setItems(items); E+ 20->
setStartIndex(0); rNp#5[e
} Xpwom'
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public PaginationSupport(List items, int 2wvDC@
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totalCount, int startIndex){ F
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setPageSize(PAGESIZE); j]SkBZgik
setTotalCount(totalCount); ?yK\L-ad
setItems(items); ]aL}&GlHt
setStartIndex(startIndex); $vz%
} ^Yz05\
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public PaginationSupport(List items, int e vuP4-[y
=<xbE;,0
totalCount, int pageSize, int startIndex){ k=_@1b-
setPageSize(pageSize); W -&5
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setTotalCount(totalCount); _Oq\YQb v
setItems(items); miqCUbcU
setStartIndex(startIndex); xM\ApN~W
} K(S/D(\
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publicList getItems(){ :B~c>:
return items; fO nvC*
} w.H+$=aK
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publicvoid setItems(List items){ <^{: K`
this.items = items; +6atbbe}
} W^f#xrq>
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publicint getPageSize(){ O6]~5&8U.
return pageSize; W[s>TDc`v
} EM}z-@A>
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publicvoid setPageSize(int pageSize){ H=C;g)R
this.pageSize = pageSize; P+h&tXZn8
} 67?5Cv
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publicint getTotalCount(){ lfP|+=^B
return totalCount; pkx>6(Y
} RSC-+c6 1
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publicvoid setTotalCount(int totalCount){ -f=hL7NW
if(totalCount > 0){ /jD'o>
this.totalCount = totalCount; KG$2u:n
int count = totalCount / ig{5]wZ(
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pageSize; `Fj(g!`
if(totalCount % pageSize > 0) J^4k}
count++; 2wCRT}C
indexes = newint[count]; 8n? .w:Y/
for(int i = 0; i < count; i++){ L_,U*Jyo
indexes = pageSize * X[<9+Q-&
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i; :F&WlU$L
} "f_Z.6WMY
}else{ a2TC,
this.totalCount = 0; }|,y`ui\
} "T|\
} ;H lv
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publicint[] getIndexes(){ 3QpTO,
return indexes; <X?F :?Mk
} nP^$p C
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publicvoid setIndexes(int[] indexes){ %:*HzYf
this.indexes = indexes; 32yNEP{
} eORt
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publicint getStartIndex(){ DZue.or
return startIndex; s><co]
} AM>:AtY
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publicvoid setStartIndex(int startIndex){ bb{+
if(totalCount <= 0) 8{C3ijR
this.startIndex = 0; Tx*m
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elseif(startIndex >= totalCount) #82B`y<<y/
this.startIndex = indexes hlRE\YO&8R
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[indexes.length - 1]; -MjRFa
elseif(startIndex < 0) KVuv%?
this.startIndex = 0; 0NxaQ`\
else{ (Gcl,IW
this.startIndex = indexes cc[w%jlA#
yWzTHW`)Mr
[startIndex / pageSize]; &>o)7H];
} :R)IaJ6)
} DI_mF#5q
.
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publicint getNextIndex(){ H|Ems}b
int nextIndex = getStartIndex() + a|.u;
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pageSize; o0 Ae*Y0
if(nextIndex >= totalCount) < -Nj
return getStartIndex(); Y*Pr
else {8' 5
return nextIndex; ' vwBG=9C
} 6{M.S}.^
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publicint getPreviousIndex(){ GOt@x9%
int previousIndex = getStartIndex() - /?sV\shy
[#:k3aFz
pageSize; ?U |lZ~o
if(previousIndex < 0) |fUSq1//
return0; y{&,YV&_h
else hXCDlCO
return previousIndex; D)Zv
} DCj!m<Y&
!>Xx</iD1
} L|<Mtw
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抽象业务类 }^H_|;e1p
java代码: *b&|
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/** g0l- n
* Created on 2005-7-12 9;PtYdJ8
*/ xRfX:3
package com.javaeye.common.business; PF.HYtZqK
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import java.io.Serializable; V|7 cdX#H
import java.util.List; yxH[uJpb
(f)QEho7
import org.hibernate.Criteria; FEkx&9]
import org.hibernate.HibernateException; >(3y(1;
import org.hibernate.Session; ;/v^@
import org.hibernate.criterion.DetachedCriteria; u>BR WN
import org.hibernate.criterion.Projections; %vW@_A~
import VD4(
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org.springframework.orm.hibernate3.HibernateCallback; m`/OO;/;
import FX{Sb"
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org.springframework.orm.hibernate3.support.HibernateDaoS aa|xZ
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upport; YJ6Xq||_
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import com.javaeye.common.util.PaginationSupport; :0J;^@
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public abstract class AbstractManager extends PH6uP]
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HibernateDaoSupport { j9%=^ZoQj
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privateboolean cacheQueries = false; zQ6otDZx
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privateString queryCacheRegion; [|vdr.
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publicvoid setCacheQueries(boolean ZjWI~"]
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cacheQueries){ #}o*1
this.cacheQueries = cacheQueries; 3:s!0ty"
} G22u+ua
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publicvoid setQueryCacheRegion(String o^mW`g8[
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queryCacheRegion){ A\LMmg
this.queryCacheRegion = Q/I/>6M7UZ
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queryCacheRegion; .^eajb`:
} l4RZ!K*X_"
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publicvoid save(finalObject entity){ Nzf tc
getHibernateTemplate().save(entity); Lc=t,=OhGe
} `Ps&N^[
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publicvoid persist(finalObject entity){ Ch>r.OfP
getHibernateTemplate().save(entity); )m|)cLT&
} f]Xh7m(Gh
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publicvoid update(finalObject entity){ 1
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getHibernateTemplate().update(entity); zt6GJz1q
} Kqm2TMO]>V
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publicvoid delete(finalObject entity){ 7*.nd
getHibernateTemplate().delete(entity); :>f}rq
} /@ m]@
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publicObject load(finalClass entity, /V0[Urc@
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finalSerializable id){ 6o6I]QL
return getHibernateTemplate().load n86LU Sj5
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(entity, id); x. 8fxogz
} e w?4;
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publicObject get(finalClass entity, Y'*oW+K
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finalSerializable id){ f}=>c|Do
return getHibernateTemplate().get H}?"2jF
id+ ~ V
(entity, id); R.(PZC vS
} Qco8m4n
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publicList findAll(finalClass entity){ ;Nk,bb K
return getHibernateTemplate().find("from |0OY>5
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" + entity.getName()); H\RejGR
} 2u Zb2O
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publicList findByNamedQuery(finalString Ogv9_X8
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namedQuery){ {>g{+Eq
return getHibernateTemplate ia@ |+r
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().findByNamedQuery(namedQuery); Y O&@
} 2D UY4Ti
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publicList findByNamedQuery(finalString query, %:t! u&:q
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finalObject parameter){ fJOwE
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return getHibernateTemplate b+1!qNuCW#
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().findByNamedQuery(query, parameter); L+N\B@ 0-
} M0yv=g
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publicList findByNamedQuery(finalString query, Qp7h|<
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finalObject[] parameters){ =WT&unw}
return getHibernateTemplate \#4mPk_"
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().findByNamedQuery(query, parameters); Me79:+d
} S4\a"WYg
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publicList find(finalString query){ bgLa`8
return getHibernateTemplate().find 4O<sE@X
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(query); ]"}BqS0
} hjyM xg;Q?
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publicList find(finalString query, finalObject %_."JT$v{
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parameter){ q
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return getHibernateTemplate().find =p^$>o
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(query, parameter); ?Z2`8]-E
} T*:w1*:
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public PaginationSupport findPageByCriteria ; [G:
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(final DetachedCriteria detachedCriteria){ URceq2_
return findPageByCriteria yDfH`]i)U
nNq<x^@83
(detachedCriteria, PaginationSupport.PAGESIZE, 0); l`.z^+!8@
} D&i\dgbK
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public PaginationSupport findPageByCriteria %N)B8A9kh
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(final DetachedCriteria detachedCriteria, finalint SIapY%)h
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startIndex){ dP?prT
return findPageByCriteria K[kK8i+(
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(detachedCriteria, PaginationSupport.PAGESIZE, oUwo!n}
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startIndex); <o/!M6^:
} b{qN7X~>
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public PaginationSupport findPageByCriteria ~P#mvQE)
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(final DetachedCriteria detachedCriteria, finalint ltfKqY-
<3!Al,!ej@
pageSize, )by7[I0v
finalint startIndex){ Tf~eH!~0
return(PaginationSupport) iLch3[p%
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getHibernateTemplate().execute(new HibernateCallback(){ <Y."()}GeH
publicObject doInHibernate o2X95NiH
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(Session session)throws HibernateException {
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Criteria criteria = 5mQ@&E~#W
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detachedCriteria.getExecutableCriteria(session); U|]cB
int totalCount = S=ZZ[E_~S
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((Integer) criteria.setProjection(Projections.rowCount PJiU2Y33
o`QNZN7/}
()).uniqueResult()).intValue(); x(._?5
criteria.setProjection w+/`l*
Z/%FQ
(null); kV+^1@"
List items = Wk\(jaL%
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criteria.setFirstResult(startIndex).setMaxResults ydy TDn
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(pageSize).list(); p;>A:i
PaginationSupport ps = u
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new PaginationSupport(items, totalCount, pageSize, M2Jf-2
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startIndex); Vf;&z$D{r
return ps; ka~_iUU4
} 0K[]UU=P=
}, true); BbI%tmA7
} :a6LfPEAX
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public List findAllByCriteria(final sSZ)C|Q
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DetachedCriteria detachedCriteria){ wkM1tKhy/
return(List) getHibernateTemplate /QY F|%7!
iqvLu{
().execute(new HibernateCallback(){ S[1<Qrv]
publicObject doInHibernate hE|P|0U,n
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(Session session)throws HibernateException { ,c4HicRJ#
Criteria criteria = ~f h
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detachedCriteria.getExecutableCriteria(session); sFc \L9 4
return criteria.list(); . :Skc
} j:h}ka/!p
}, true); \IE![=p\w
} HohCb4do
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public int getCountByCriteria(final iX$G($[l(
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DetachedCriteria detachedCriteria){ !BsQJ_H
Integer count = (Integer) ~Jk&!IE2
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getHibernateTemplate().execute(new HibernateCallback(){ tw_o?9
publicObject doInHibernate 7q+D}+ Xf
1(gs({
(Session session)throws HibernateException { 7v*gwBH
Criteria criteria = ZeP=}0TGjn
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detachedCriteria.getExecutableCriteria(session); Qs elW]
return j|t=%*
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criteria.setProjection(Projections.rowCount rP:g`?*V
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()).uniqueResult(); }:0_%=)N<
} ob\-OMNs@
}, true); K6kz{R%`
return count.intValue(); inWLIXC,
} ,X.[37
} z:>cQUYl
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用户在web层构造查询条件detachedCriteria,和可选的 |NuMDVd+s
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 CRK%^3g
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PaginationSupport的实例ps。 k7^hcth
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ps.getItems()得到已分页好的结果集 P.y +jyu
ps.getIndexes()得到分页索引的数组 AJ\&>6GZ(b
ps.getTotalCount()得到总结果数 zmo2uUEd
ps.getStartIndex()当前分页索引 i"h\*B=
ps.getNextIndex()下一页索引 8zp?WUb
ps.getPreviousIndex()上一页索引 ./#YUIC
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N d].(_
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 Fw 0m(7
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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 '^UHY[mX8
0k
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一下代码重构了。 Fi/iA%,
}bb,Iib
我把原本我的做法也提供出来供大家讨论吧: gXxi; g
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首先,为了实现分页查询,我封装了一个Page类: }u_D{ bz
java代码: `HX:U3/
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/*Created on 2005-4-14*/ Pk;\^DRC
package org.flyware.util.page; `D4Wg<,9
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/** x3q^}sj%
* @author Joa y
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* Gyq 6?
*/ ?()*"+N(ck
publicclass Page { W'C>Fn}lO?
7hHID>,o9%
/** imply if the page has previous page */ 0V:H/qu8>
privateboolean hasPrePage; |'h(S|
L/i'6(="
/** imply if the page has next page */ z@,pT"rb
privateboolean hasNextPage; _%e8GWf
Xdn&%5rI
/** the number of every page */ B4y_{V
privateint everyPage; P T;{U<5
3"h*L8No
/** the total page number */ p*Z<DEh#
privateint totalPage; ,X|Oe@/
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/** the number of current page */ "*bLFORkq'
privateint currentPage; K(+=V)'Dz
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/** the begin index of the records by the current |{#St-!-7
Ok!P~2J
query */ 4|?(LHBD)
privateint beginIndex; 1aAOT6h
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/** The default constructor */ zDvV%+RW)
public Page(){ U1YqyG8
.RroO_H
} 7h\is
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/** construct the page by everyPage RdX+:!lD
* @param everyPage tK3$,9+
* */ > "hP
public Page(int everyPage){ hk?i0#7W
this.everyPage = everyPage; HZ9 >4G3
} {y"Kn'1
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/** The whole constructor */ nE]rPRU}[
public Page(boolean hasPrePage, boolean hasNextPage, YuhfPa
n*\o. :f
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int everyPage, int totalPage, mnA_$W3~I
int currentPage, int beginIndex){ S)EF&S(TC
this.hasPrePage = hasPrePage; <V^o.4mOg>
this.hasNextPage = hasNextPage; HM% +Y47a
this.everyPage = everyPage; U^_\V BAk
this.totalPage = totalPage; bc(MN8b ]j
this.currentPage = currentPage; -C2!`/U
this.beginIndex = beginIndex;
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} (-S^L'v62v
<-1:o*8:}
/** rZgu`5<a
* @return -
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* Returns the beginIndex. #ft9ms#N
*/ |sGJum&=
publicint getBeginIndex(){ 7&id(&y/
return beginIndex; ,1I-%6L
} {iyJHY
LVUA"'6V
/** `+Nv=vk
* @param beginIndex vd%AV(]<LJ
* The beginIndex to set. "nz\YQdg
*/ r5gqRh}+
publicvoid setBeginIndex(int beginIndex){ '-"[>`[q
this.beginIndex = beginIndex; Z`kVyuQ
} 2sGKn
a
:
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/** ^|<>`i6
* @return _OGv2r
* Returns the currentPage. qlM<X?
*/ o}=*E
publicint getCurrentPage(){ P].Eb7I
return currentPage; >~ *wPoW
} ,|*Gr"Q=
"EpH02{i
/** ,x\qYz+7|
* @param currentPage %vO(.A+
* The currentPage to set. `\@n&y[`7
*/ :?UcD_F
publicvoid setCurrentPage(int currentPage){ <oXBkCi0r
this.currentPage = currentPage; 3[Q7'\
} E,d<F{=8,o
29=ob("
/** s/ABT.ZO
* @return 8Y-*rpLy
* Returns the everyPage. +tk`$g
*/ Z,p@toj'
publicint getEveryPage(){ d%I7OBBx@
return everyPage; o~'p&f
} TFOx=_.%i
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/** Lv@WI6DM
* @param everyPage UIU Pi
gd
* The everyPage to set. qMEd
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*/ 0to`=;JI
publicvoid setEveryPage(int everyPage){ nP[Z6h
this.everyPage = everyPage; KC"S06
} Rk5#5R n
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/** jW7ffb
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* @return ekY)?$v3
* Returns the hasNextPage. 6*B%3\z)
*/ GPni%P#a@0
publicboolean getHasNextPage(){ 5`3x(=b
return hasNextPage; r?u4[
Oe#
} }8AH/
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/** 0e&&k
* @param hasNextPage 4IW
fp&Q!
* The hasNextPage to set. --diG$x.
*/ >!qtue7B
publicvoid setHasNextPage(boolean hasNextPage){ k>i`G5Dh
this.hasNextPage = hasNextPage; )^8[({r~
} R<fF
^^
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/** 4RctYMz
* @return -uN{28;@
* Returns the hasPrePage. 6|lsG6uf
*/ v5@4|u3ds
publicboolean getHasPrePage(){ 0Sk~m4fj(
return hasPrePage; w;Azxcw
} %AJ9fs4/
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/** Xl1% c7r.1
* @param hasPrePage kIa16m
* The hasPrePage to set. 9:g A0Z
*/ _1RvK? ;.{
publicvoid setHasPrePage(boolean hasPrePage){ E5A"sB
this.hasPrePage = hasPrePage; 3f$n8>mq
} D5xQ
CH(Y.Kj-
/** dSKvs"
* @return Returns the totalPage. 5s\;7>
* Ge({sy>X
*/ &0f/F:M
publicint getTotalPage(){ &u^]YE{
return totalPage; x~uDCbL
} 3=U#v<
>o13?-S%e
/** ELV~
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* @param totalPage wZ0bD&B
* The totalPage to set. YJ6:O{AL1
*/ w:nH_x#C4
publicvoid setTotalPage(int totalPage){ U]+I P;YS
this.totalPage = totalPage; L8n?F#q
} @r[SqGa:
mW {uChHP
} l?IeZisX
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RQ*
Z,AY<[/C
lO|LvJyx
y+Nw>\|S
上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 FO(QsR=\s
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个PageUtil,负责对Page对象进行构造: y|+5R5}K
java代码: T~$Eh6
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/*Created on 2005-4-14*/ b 1.S21
package org.flyware.util.page; L_9uwua.B~
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import org.apache.commons.logging.Log; x>mI$K(6M
import org.apache.commons.logging.LogFactory; wQhu U
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/** g]JJ!$*1
* @author Joa Z" H; t\P
* *tT}N@<%
*/ PA803R74
publicclass PageUtil { .7
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privatestaticfinal Log logger = LogFactory.getLog \>*.+?97
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w
(PageUtil.class); l
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/** ts(u7CJd
* Use the origin page to create a new page
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* @param page _1Rw~}O
* @param totalRecords 4Dn&+=fq
* @return t
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*/ Z5oDj|&l}
publicstatic Page createPage(Page page, int P@G U2[1
)TVd4s(e
totalRecords){ "y*3p0E
return createPage(page.getEveryPage(), #J3}H
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page.getCurrentPage(), totalRecords); V:j^!*
} *-fd$l.
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/** Xu~N97\G
* the basic page utils not including exception At<MY`ka
vy5Fw&?"
handler Qp[
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* @param everyPage (y?F8]TfM
* @param currentPage A0@,^|]
* @param totalRecords RLL
ph
* @return page fnr8{sr.2Z
*/ Iv3yDL;
publicstatic Page createPage(int everyPage, int yU/?4/G!
.]KC*2
currentPage, int totalRecords){ gloG_*W
everyPage = getEveryPage(everyPage);
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currentPage = getCurrentPage(currentPage); <)LR
int beginIndex = getBeginIndex(everyPage, _3%:m||,XP
><IWF#kUA
currentPage); IEm~^D#<=
int totalPage = getTotalPage(everyPage, "1a!]45 +
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totalRecords); 6Hb a@Q1`
boolean hasNextPage = hasNextPage(currentPage, z__t8yc3
PN9vg9'
totalPage); E=,b;S-
boolean hasPrePage = hasPrePage(currentPage); Oprfp^L
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returnnew Page(hasPrePage, hasNextPage, I:oEt
everyPage, totalPage, Ebj0 {ZL
currentPage, 1 Vc_jYO@
ECM#J28D
beginIndex); =$bF[3D
} -le^ 5M7
kq(><T
privatestaticint getEveryPage(int everyPage){ F~E)w5?\O
return everyPage == 0 ? 10 : everyPage; 1Zp/EYWa{
} E <j=5|0t
6J JA"] `
privatestaticint getCurrentPage(int currentPage){ :ln|n6X
return currentPage == 0 ? 1 : currentPage;
Z R=[@Oi
} 2uT6M%OC
UE5,Ml~X
privatestaticint getBeginIndex(int everyPage, int ;xw9#.d#D
_~CJitR3
currentPage){ z8S]FpM6
return(currentPage - 1) * everyPage; Z/: yYSq
} E Lq1
`$JZJ!,A
privatestaticint getTotalPage(int everyPage, int 6W3oIt
]Oo!>iTQi
totalRecords){ :epB:r
int totalPage = 0; xWa[qCr
0&|M/
if(totalRecords % everyPage == 0) [R8BcO(
totalPage = totalRecords / everyPage; r9bAbE
bI
else A0A|c JP
totalPage = totalRecords / everyPage + 1 ; W[`ybGR<
(>u1O V
return totalPage; ND?"1/s
} E]&N'+T
C^'r>0
privatestaticboolean hasPrePage(int currentPage){ /<[_V/g[t?
return currentPage == 1 ? false : true; ZHeue_~x4
} Uv.Xw} q
s/J7z$NEU
privatestaticboolean hasNextPage(int currentPage, $1d{R;b[
O\o@]
int totalPage){ Cb<7?),vK
return currentPage == totalPage || totalPage == or;VmU8$zb
3j$,L(
0 ? false : true; *Uy>F[%@
} ,3}+t6O"
a9^})By&
,Iz9!i
J"
} tGl|/
v_%6Ly
S{2;PaK
+ru `Zw5,
b0h\l#6
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 KgD$P(J:[
CiHx.5TiC
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 #WG;p(?:
3K~^H1l
做法如下: D1>*ml
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 @|ZUyat
b|x B<
的信息,和一个结果集List: x%@M*4:&
java代码: GadY#]}(
/#:*hn
]x8Y]wAU&{
/*Created on 2005-6-13*/ +U,t*U4,
package com.adt.bo; ]
X]!xvN@
B&59c*K
import java.util.List; $?:IRgAr
.@mZG<vg
import org.flyware.util.page.Page; s/~[/2[bnf
?
B|i
/** im:[ViR {
* @author Joa t W
*/ s2N'Ip
publicclass Result { q2*)e/}H
@pv:uON\
private Page page; Qz{Vl>"
BSSehe*
private List content; .uX(-8n ~
~v/`
`s
/** (kK8
Ox fF
* The default constructor *Z.{1
*/ Fv/{)H<:y
public Result(){ (qc<'$o
super(); oliVaavj
} 13 JG[,w
;2fzA<RkK
/** K]>4*)A:
* The constructor using fields {nA+-=T
* ~KGE(o4p
* @param page "k [$euV
* @param content $[cB6
*/ UDcr5u eKn
public Result(Page page, List content){ IWN18aaL?
this.page = page; Gk58VODo
this.content = content; VOATza`
} ]NWcd~"b!Z
KU+u.J
/** +dq2}gM
* @return Returns the content. R"t2=3K
*/ +ZE"pA^C
publicList getContent(){ y\iECdPU
return content; zKYN5|17
} 5>1c4u`x
F)'_,.?0
/** Bgsi$2hI
* @return Returns the page. }L{GwiDMDl
*/ =.m/X>
public Page getPage(){ srImk6YD
return page; #z_.!E
} bccf4EyQ
Y
\:n<&<aVSr
/** ZS_
z
* @param content T|YMU?4
* The content to set. Z>1yLt@ls
*/ [["eK9}0
public void setContent(List content){ ] 4*E:
this.content = content; ph2
_P[S'
} Vn/FW?d7
4uE/!dT
/** ;uZq_^?:9&
* @param page Jl6biJx
* The page to set. (8W?ym
*/ pF~aR]Q
publicvoid setPage(Page page){ }.=wQ_
this.page = page; +'[*ikxD=g
} 11A;z[Zk
} g6SZ4WV
sFgsEKs
8jky-r
uAk>VPuuZ
?6MUyH]a
2. 编写业务逻辑接口,并实现它(UserManager, 9I1`* 0A
gI Gi7x
UserManagerImpl) KAr5>^<zw
java代码: 4>HQ2S{t
!Xq5r8]
AQ"rk9Z
/*Created on 2005-7-15*/ gd]k3XN$f
package com.adt.service; ?%Pi#%P
hx~rq`{
import net.sf.hibernate.HibernateException; J?&%fI
6LT.ng
import org.flyware.util.page.Page; bSTTr<W
z=rSb4"W
import com.adt.bo.Result; >dDcm
P!&yYR\
/** S*ie$}ZX
* @author Joa =}+xD|T
*/ WZbRR.TxO
publicinterface UserManager { U'} [:h~)
leXdxpc
public Result listUser(Page page)throws 1l}fX}5%I;
d=HD!
e
HibernateException; Y1DbBDk
B|AIl+y
} -BrJ5]T>*
?IiFFfs
A;;OGJ,!\
CT=5V@_u\
immf\
java代码: 8tT/w5
_tnoq;X[
/ EVXkf0
/*Created on 2005-7-15*/ |[/XG2S
package com.adt.service.impl; |5BvVqn
kL -f@CD
import java.util.List; TPi{c_
]
j'SGZnsy*
import net.sf.hibernate.HibernateException; 4"+v:t)z6{
D<^K7tJui
import org.flyware.util.page.Page; EuD$^#
import org.flyware.util.page.PageUtil; #6 $WuIG
k,/2]{#53d
import com.adt.bo.Result; R8j\CiV17
import com.adt.dao.UserDAO; +DSZ(Zb4qY
import com.adt.exception.ObjectNotFoundException; pf&SIG
import com.adt.service.UserManager; xwijCFI*
'^:q|h
/** uHt@;$9A
* @author Joa 7C@m(oK
*/ *.-qbwOg
publicclass UserManagerImpl implements UserManager { OV7SLf
n*eqM2L
private UserDAO userDAO; pG$l
xHn "D@
/** g`H;~ w
* @param userDAO The userDAO to set. RWGAxq`9f
*/ 2&<&q J
publicvoid setUserDAO(UserDAO userDAO){ 6?l|MU"Q.
this.userDAO = userDAO; ~:UAL}b{\~
} ~=Fp0l)#
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/* (non-Javadoc) B,{Q[
* @see com.adt.service.UserManager#listUser [g lhru=+
3=^B
&AB
(org.flyware.util.page.Page) v*@R U
*/ kE{-h'xADD
public Result listUser(Page page)throws K=J">^uW
3TT?GgQ
HibernateException, ObjectNotFoundException { fjy2\J!
int totalRecords = userDAO.getUserCount(); \'P79=AU
if(totalRecords == 0) u< 5{H='6
throw new ObjectNotFoundException ?Aky!43
ue!wo-|#G
("userNotExist"); Q~)A
fa{
page = PageUtil.createPage(page, totalRecords); 'u%SI]*;>
List users = userDAO.getUserByPage(page); 2TX.%%Ze
returnnew Result(page, users); ']>/$[!
} 1lHBg
t[bZg9;
} NKu*kL}W=
X}]g;|~SN
FzQ6UO~'
Z}r9jM
9Ui|8e~=
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 .:TSdusr~
BHIC6i%
询,接下来编写UserDAO的代码: m/1;os5+8
3. UserDAO 和 UserDAOImpl: R-BN}ZS
java代码: m)xz_Plc
!MD uj
l|
QQ
/*Created on 2005-7-15*/ PA${<wyBR_
package com.adt.dao; +C`zI~8
R"{oj]d;$F
import java.util.List; ,) 3Eog\-
0d #jiG
import org.flyware.util.page.Page;
<Lfo5:.
qfB!)Y
import net.sf.hibernate.HibernateException; U$6(@&P!
>Te h ?P
/** [kPF J f
* @author Joa kBJx`tjtp
*/ |&0Cuwt
publicinterface UserDAO extends BaseDAO { #9@UzfZAwT
- f%J_`
publicList getUserByName(String name)throws b:6e2|xf?
Ve|=<7%%S
HibernateException; ~&Y%yN^
4k=LVu]Kcr
publicint getUserCount()throws HibernateException; 43o!Vr/S
6vebGf
publicList getUserByPage(Page page)throws tp3
!6I6
Z oQPvs7_
HibernateException; 9{n?Jy
|Ht~o(]&&/
} A&qZ:&(OM
!wEz=
i
q
`^5<
} !RBH(m%
8H2A<&3i
java代码: a3E.rr;b
}Uunlz<
LE4P$%>H
/*Created on 2005-7-15*/ kZH IzU
package com.adt.dao.impl; D=!5l4
Wx F0LhM
import java.util.List; bWfT-Jewh
35fsr=
import org.flyware.util.page.Page; Uk= L?t
2/#%^,Kb2
import net.sf.hibernate.HibernateException; g.eMGwonTJ
import net.sf.hibernate.Query; Nd61ns(N
5vqh09-FB
import com.adt.dao.UserDAO; z)]Br1
8z'_dfP=5
/** ttA0*
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* @author Joa PitDk
1T
*/ {qPu}?0
public class UserDAOImpl extends BaseDAOHibernateImpl 9|1J pb
w]Z:Y`
implements UserDAO { IRB BLXv7\
?UV!^w@L:0
/* (non-Javadoc) g)Dg=3+>
* @see com.adt.dao.UserDAO#getUserByName Sv|jR r'
/WJ+e
(java.lang.String) R7~#7qKQB
*/ Qwu~{tf+'
publicList getUserByName(String name)throws vHxLn/
8d*W7>rq
HibernateException { jp P'{mc
String querySentence = "FROM user in class ;`-@L
2vx1M6a)L
com.adt.po.User WHERE user.name=:name"; ! )PV-[2
Query query = getSession().createQuery AWn$od`#s
4]%v%64U
(querySentence); },(Ln%M
query.setParameter("name", name); ~xV|<;
return query.list(); Ym/y2B(
} 0X[uXf
s2Hx?~
/* (non-Javadoc) 6F4OISy%3
* @see com.adt.dao.UserDAO#getUserCount() VLs%;|`5D
*/ ;$$.L
bb8
publicint getUserCount()throws HibernateException { 9a lMC
int count = 0; ;Zow C#j
String querySentence = "SELECT count(*) FROM f<v:Tg.[
J}3 7 9
user in class com.adt.po.User"; bO\E)%zp
Query query = getSession().createQuery a>XlkkX
$3Srr*
(querySentence); qJf=f3
count = ((Integer)query.iterate().next :Vl2\H=P
;Alw`'
()).intValue(); EwH_k
return count; <\C/;
} }qn@8}
w*7BiZ{s<
/* (non-Javadoc) :bV1M5
* @see com.adt.dao.UserDAO#getUserByPage DQRr(r~2Kj
yi$ Jk}w
(org.flyware.util.page.Page) ohj(1jt
*/ |B/A)(c
yV
publicList getUserByPage(Page page)throws AEr8^6
!$5.\D
HibernateException { F F7
String querySentence = "FROM user in class Ua=w;h
!<I3^q
com.adt.po.User"; S@PAtB5
Query query = getSession().createQuery "J(W)\
UOAL7
(querySentence); pz]#/Ry?
query.setFirstResult(page.getBeginIndex()) Zbobi,
.setMaxResults(page.getEveryPage()); ppu WcGo
return query.list(); :*MqYny&
} >qhoGg
zOzobd
} ^ H )nQ
p!]$!qHO(
HHU0Nku@ho
Q1?09
sGdlS&08(
至此,一个完整的分页程序完成。前台的只需要调用 Az"(I>VfD
}"CX`
userManager.listUser(page)即可得到一个Page对象和结果集对象 S LSbEm
}HC6m{vH(
的综合体,而传入的参数page对象则可以由前台传入,如果用 +{F2hEYP
vPbmQh ex
webwork,甚至可以直接在配置文件中指定。 3
2MdDa
bQFMg41*w7
下面给出一个webwork调用示例: mzkv/
java代码: r p^Gk
<>tQa5;
\uTy\KA
/*Created on 2005-6-17*/ !?u{2D
package com.adt.action.user; ~gAp`Q
;mw$(ZKa#
import java.util.List; _K5R?"H0
<5wk~|@t
import org.apache.commons.logging.Log; S"wn0B$"
import org.apache.commons.logging.LogFactory; .3JLa8y
import org.flyware.util.page.Page; xOAA1#
~$\9T.tre2
import com.adt.bo.Result; Fw!TTH6l0
import com.adt.service.UserService; 6*]g~)7`Q~
import com.opensymphony.xwork.Action; q;<=MO/
m5/d=k0l
/** B"rfR_B2M#
* @author Joa f8c'`$O
*/ _R 6+bB$
publicclass ListUser implementsAction{ ySEhi_)9^
Xi~%,~
privatestaticfinal Log logger = LogFactory.getLog
2l#c?]TA
YAoGVey
(ListUser.class); f,_EPh>
#uzp
private UserService userService; <*4BT}r,^2
BD(Y=g
private Page page; >.)m|,
l9eCsVQ~V
privateList users; dvl'Sq<
fd<a%nSD
/* CC<(V{Png
* (non-Javadoc) ZWH9E.uj
* Jiv%Opo/|
* @see com.opensymphony.xwork.Action#execute() WE|-zo
*/ 'zg; *)x1/
publicString execute()throwsException{ wcI?.
Result result = userService.listUser(page); |\W9$V
page = result.getPage(); i:coNK)4
users = result.getContent(); qP}187Q1
return SUCCESS; +%%Ef]
} }+{?
Ms
} qf=5v
/** f=L&>X
* @return Returns the page. Q*J8`J:#^R
*/ ~5Cid)Q}@o
public Page getPage(){ &Is}<Ew
return page; &*4C{N
} nbECEQ:|B
\[57Dmo
/** 3iI 4yg
* @return Returns the users. jrl'?`O
*/ y|7sh
publicList getUsers(){ fUg<+|v*
return users; (1pR=
} m'b9 f6
MN.h,^b
/** Ddr.kXIpo
* @param page 2.>WR~\
* The page to set. Sz_{ #-
*/ Z?);^m|T
publicvoid setPage(Page page){ o;zU;pkB
this.page = page; @|jLw($Ly
} PXRkK63
a
At<36{?
/** )#H&lH
* @param users L^{1dVGWNa
* The users to set. 6Kbc:wlR
*/ *:+&SxL
publicvoid setUsers(List users){ X^td`}F/=V
this.users = users; djk?;^8
} Jx jP'8
+~x'1*A_
/** %lbDcEsf9
* @param userService A%[BCY_
* The userService to set. s.#%hPX{
*/ |}-bMQ|
publicvoid setUserService(UserService userService){ .yF@Ow
this.userService = userService; cOq'MDr
} 0'3f^Ajf
} <?&Y_
2lc
wi gs1
jGSY$nt9
i eL7jN,'m
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, ]VCVV!G_=n
9Ev<t\B
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 5Qh$>R4!"
VK]cZ%)
么只需要: 5{"v/nXV
java代码: XYh)59oM%
x* 9 Xu"?
J\@W+/#dF
<?xml version="1.0"?> !2o1c
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork [qL{w&R
~Oc:b>~
1.0//EN" "http://www.opensymphony.com/xwork/xwork- b4R;#rm
3OlXi9>3
1.0.dtd"> z]%c6ty
mM $|cge"
<xwork> ^ 5D%)@~
..K@'*u
<package name="user" extends="webwork- -`8pahI
+v.<Fw2k#
interceptors"> ]<xzCPB
B@ xjwBUk
<!-- The default interceptor stack name RDSkFK( D
{O=PVW2S
--> #aua6V!"
<default-interceptor-ref z8@[]6cW
K7-z.WTUR
name="myDefaultWebStack"/> 8)o%0#;0B
hE;|VSdo
<action name="listUser" cp)BPg
T2ZB(B D
class="com.adt.action.user.ListUser"> Dx5X6 t9=
<param +e87/\5
4aGVIQ
name="page.everyPage">10</param> $VxKv7:
<result GiK4LJ~cH)
hjgB[
&U>
name="success">/user/user_list.jsp</result> >lV'}0u)
</action> Nrn_Gy>|D
}1#prQ0F
</package> A`:a
T{j
U!\~LKfA
</xwork> xep8CimP'
W;T5[
UasU/Q <
W>j@E|m$
]<*-pRN
,x=S)t
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 ^?8/9o
;EB^1*AEw
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。 b]b+PK*h
sR4B/1'E
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 ^)UX#D3b
6Vj=SYK
&\y`9QpVF
AGGT]
58|
!+u
K@z&G
我写的一个用于分页的类,用了泛型了,hoho agkGUK/
+^DDWVp
java代码: Z0[d;m*
]Zz.n5c
ueyQ&+6r
package com.intokr.util; 2}n7f7[/b
\2^o,1r/
import java.util.List; +'$5Jtz
SU5O+;{`'
/** G1fC'6$3
* 用于分页的类<br> cN-$;Ent
* 可以用于传递查询的结果也可以用于传送查询的参数<br> jVPX]8
* SJ2l6
* @version 0.01 UDT\Xc
* @author cheng f~10 iD
*/ KL yI*`
public class Paginator<E> { zP&D
privateint count = 0; // 总记录数 =NmW}x|n
privateint p = 1; // 页编号 .b?Aq^i8
privateint num = 20; // 每页的记录数 5P{[8PZxbV
privateList<E> results = null; // 结果 cLf<YF
`W:z#uNG]
/** ~1&WR`U
* 结果总数 Ew JNpecX
*/ TM5 Y(Q*
publicint getCount(){ EsS$th)d
return count; P1R5}i
} 2){O&8 A
PJYUD5
publicvoid setCount(int count){ wF9L<<&B
this.count = count; O6ph_$nt.
} B@U'7`v
edo+ o{^
/** nMK$&h,{
* 本结果所在的页码,从1开始 k1.%ZZMM
* c'>_JlG~
* @return Returns the pageNo. x"n++j
*/ & 'CUc/,
publicint getP(){ npd:a Gx
return p; |BUgsE
} \(RD5@=!4#
S1[, al
/** = N;5T
* if(p<=0) p=1 R nwFxFIQ
* &f}w&k2yj
* @param p F{4v[WP)
*/ $A`m8?bY
publicvoid setP(int p){ dVUe!S`
if(p <= 0) W4,'?o
p = 1; ('{aOiSH
this.p = p; _, E/HAX
} Cs(sar:7
>(-A"jf
/** *4e?y
* 每页记录数量 \1SC:gN*#
*/ i),bAU!+m
publicint getNum(){ 'J$@~P
return num; mITNx^p4f
} ;:&|DN3;
QWnGolN
/** vz~Oi
* if(num<1) num=1 @mJ~?d95v
*/ Mg2 e0}{
publicvoid setNum(int num){ z)(W
x">
if(num < 1) Rx.v/H
num = 1; C5~n^I|
this.num = num; r6nnRN/S=
} :w-:B^VB
+TyN;e
/** P@keg*5@
* 获得总页数 tXqX[Td`0g
*/ 2n$Wey[
publicint getPageNum(){ peF)U
!`D
return(count - 1) / num + 1; 1yZA_x15:
} L$i:~6
*:Rs\QH
/** @({=~
W^
* 获得本页的开始编号,为 (p-1)*num+1 op\$(7<d-
*/ qY$ [2]
publicint getStart(){ NYr)=&)Ke.
return(p - 1) * num + 1; *FktI\tS
} EK5$z>k>m
yQ$]`hr;
/** uorX;yekC
* @return Returns the results. %S"85#R5E
*/ tRpY+s~Fq
publicList<E> getResults(){ k qL.ZR
return results;
4g"%?xN
} x(cv}#}S8
i%JJ+9N
public void setResults(List<E> results){ Ix6\5}.c 9
this.results = results; cFt&E