Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 d*$$E
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 ]=!wMn* *
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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 `dekaRo
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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 Fv$5Zcf
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分页支持类: KM
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java代码: nb
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package com.javaeye.common.util; "`HkAW4GZa
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import java.util.List; sh;DCd
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publicclass PaginationSupport { |`vwykhezO
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publicfinalstaticint PAGESIZE = 30; >L[n4x\
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privateint pageSize = PAGESIZE; V&)Jvx}^
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privateList items; M|8vP53=q
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privateint totalCount; 8 *o*?1.
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privateint[] indexes = newint[0]; AB(WK9o
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privateint startIndex = 0; z7TMg^9#
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public PaginationSupport(List items, int 8'XAZSd(
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totalCount){ v2eLH:6
setPageSize(PAGESIZE); :jL>sGvBv
setTotalCount(totalCount); "?9rJx$
setItems(items); ;B*im
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setStartIndex(0); wT\JA4
} -wr#.8rzTT
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public PaginationSupport(List items, int wr);+.T9R
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totalCount, int startIndex){ $fifx>!
setPageSize(PAGESIZE); 7p1f*N[X
setTotalCount(totalCount); k Il!n
setItems(items); Gbj^o o
setStartIndex(startIndex); vYl2_\,Y?
} }fC=
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public PaginationSupport(List items, int Q$,AQyBlqc
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totalCount, int pageSize, int startIndex){ `>ppDQaS)W
setPageSize(pageSize); 709/'#- ^
setTotalCount(totalCount); IQZ/8UwB
setItems(items); o6bT.{8\
setStartIndex(startIndex); }jE[vVlRw
} OHRkhwF.
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publicList getItems(){ !ZxK+Xqx[
return items; M02U,!di
} Q Ev7k
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publicvoid setItems(List items){ oRkh>yj'
this.items = items; U80h0t%
} `:b*#@
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publicint getPageSize(){ I<+EXH%1,
return pageSize; lKdd3W"o
} h~EGRg
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publicvoid setPageSize(int pageSize){ XrUc`
this.pageSize = pageSize; Q DVk7ks
} njxfBA:
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publicint getTotalCount(){ )kMF~S|H
return totalCount; 0RZ[]:(
} Oa.84a
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publicvoid setTotalCount(int totalCount){ = Ed0vw
if(totalCount > 0){ X 0vcBHh
this.totalCount = totalCount; g1kYL$ o4
int count = totalCount / G!T_X*^q2U
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pageSize; Xb<>AzEM
if(totalCount % pageSize > 0) 7Is:hx|:
count++; ]\Z8MxFD
indexes = newint[count]; Lv&9s
for(int i = 0; i < count; i++){ ;mT
indexes = pageSize * +)xjw9b
*fCmZ$U:{
i; q0C%">>1#
} d/Sw.=vq
}else{ @WCA7DW!
this.totalCount = 0; }]i.z:7+
} FG!2h&k
} nEt{ltsS0
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publicint[] getIndexes(){ h6b(FTC^
return indexes; H)k V8wU
} QHXA?nBX
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publicvoid setIndexes(int[] indexes){ \
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this.indexes = indexes; $35C1"
} 1/f{1k
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publicint getStartIndex(){ r2*8.j51
return startIndex; \,xa_zeO
} H+{@VB
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publicvoid setStartIndex(int startIndex){ B:Y F|k}T
if(totalCount <= 0) W{%X1::q$
this.startIndex = 0; Vk> &
elseif(startIndex >= totalCount) pZcY[a
this.startIndex = indexes BCfmnE4%
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[indexes.length - 1]; GT7&>}FJ)
elseif(startIndex < 0) &\=Tm~
this.startIndex = 0; U8.V Rn
else{ 7`j%5%q
this.startIndex = indexes %M3L<2
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[startIndex / pageSize]; }Y^o("c(
} Q=61.lP6
} = GyABK
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publicint getNextIndex(){ d6a3\f
int nextIndex = getStartIndex() + z/]]u.UP
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pageSize; d_,Ql708f
if(nextIndex >= totalCount) w4fQ~rcUIc
return getStartIndex(); ?[uHRBR'
else C
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return nextIndex; mW$Oi++'d
}
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5 JlgnxRq
publicint getPreviousIndex(){ mlxtey6H3
int previousIndex = getStartIndex() - Y&1N*@YP
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pageSize; ^TD%l8o6
if(previousIndex < 0) 1eywnOjrj
return0; ]>Ym
else BhYvEbt
return previousIndex; $%^](-
} Z($i+L% .
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} X}xf_3N
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抽象业务类 *u-$$@|y
java代码: h\p!J-V
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/** 0hhxTOp
* Created on 2005-7-12 Rc:}%a%e
*/ >|z:CX$]
package com.javaeye.common.business; tz8fZ*n
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import java.io.Serializable; Wsgp#W+
import java.util.List; qw$9i.Z
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import org.hibernate.Criteria; ZH|q#<{l
import org.hibernate.HibernateException; a{L&RRJ
import org.hibernate.Session; &XV9_{Hm
import org.hibernate.criterion.DetachedCriteria; =IW!ZN_
import org.hibernate.criterion.Projections; U3C"o|
import QJj='+R>
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org.springframework.orm.hibernate3.HibernateCallback; oN[}i6^,e
import O\ _ro.
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org.springframework.orm.hibernate3.support.HibernateDaoS 2*<Zc|uNW
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upport; ilde<!?
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import com.javaeye.common.util.PaginationSupport; hsQDRx%H}
ht*(@MCr<
public abstract class AbstractManager extends \i/HHP[%
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HibernateDaoSupport { =
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privateboolean cacheQueries = false; vQ*RrHG?c
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privateString queryCacheRegion; h]h"-3
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publicvoid setCacheQueries(boolean P))BS
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cacheQueries){ p:TE##
this.cacheQueries = cacheQueries; \c<;!vkZ04
} U+*l!"O,
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publicvoid setQueryCacheRegion(String {?`7D:]`^
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queryCacheRegion){ .SjJG67OyA
this.queryCacheRegion = F \ls]luN
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queryCacheRegion; J/jkb3
} /6Q]f
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publicvoid save(finalObject entity){ .n1&Jsey
getHibernateTemplate().save(entity); 'KIT^k0"Ih
} F$DA/ {.D
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publicvoid persist(finalObject entity){ ,+
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getHibernateTemplate().save(entity); t$(#$Z,RS
} CDM6o!ur3
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publicvoid update(finalObject entity){ Dc@ O Mr
getHibernateTemplate().update(entity); 5"@>>"3U
} {Y@shf;
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publicvoid delete(finalObject entity){ 7tXy3-~biz
getHibernateTemplate().delete(entity); 'bJGQ[c
} Bkd$'7UT
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publicObject load(finalClass entity, _$96y]Bpi
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finalSerializable id){ \894Jqh
return getHibernateTemplate().load #?Kw
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(entity, id); ;.Bz'Q
} ns%gb!FBJX
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publicObject get(finalClass entity, b"A,q
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finalSerializable id){ o3dqsQE%
return getHibernateTemplate().get )][U6 e
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(entity, id); _i {Y0d+
} zawu(3?~)5
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publicList findAll(finalClass entity){ z^U+oG
return getHibernateTemplate().find("from +Q u.86dH
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" + entity.getName()); ]B,tCBt
} 9 Gd6/2
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publicList findByNamedQuery(finalString oh< -&3Jn
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namedQuery){ O3@DU#N&s
return getHibernateTemplate uVUU1@
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().findByNamedQuery(namedQuery); n#g_)\
} A:< %>
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publicList findByNamedQuery(finalString query, KE3`5Y!
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finalObject parameter){ u -t=M]
return getHibernateTemplate -}%J3j|R:
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().findByNamedQuery(query, parameter); FL'}~il
} 9$\s
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publicList findByNamedQuery(finalString query, :oZ<[#p"*
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finalObject[] parameters){ 2.aCo, Kb;
return getHibernateTemplate QcL@3QC
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().findByNamedQuery(query, parameters); D_d>A+
} xRD+!3
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publicList find(finalString query){ ;|WUbc6&g
return getHibernateTemplate().find OM[MRZEh G
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(query); GK}52,NM
} M!J7Vj?Ps
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publicList find(finalString query, finalObject kM506U<g
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parameter){ vW=-RTRH
return getHibernateTemplate().find Qp:I[:Lr;
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(query, parameter); i]r(VKX
} )$:1e)d
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public PaginationSupport findPageByCriteria Rlewp8?LB
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(final DetachedCriteria detachedCriteria){ ?gMx
return findPageByCriteria `f>!/Zm%9
Q-w# !<L.
(detachedCriteria, PaginationSupport.PAGESIZE, 0); :cC$1zv@
} Q]K` p(
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public PaginationSupport findPageByCriteria ~A=zjkm
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(final DetachedCriteria detachedCriteria, finalint P+j=]Yg
}*6BaB
startIndex){ tVRN3fJH
return findPageByCriteria `3F#k[IR
/Sj~lHh
(detachedCriteria, PaginationSupport.PAGESIZE, +]%S}<R
T'5{p
startIndex); |Mq+QDTTw~
} G\gjCp?!
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public PaginationSupport findPageByCriteria rM7qBt
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(final DetachedCriteria detachedCriteria, finalint 6j(/uF4!#
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pageSize, g0grfGo2p
finalint startIndex){ m;dwt1'Zw
return(PaginationSupport) >R F|Q
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getHibernateTemplate().execute(new HibernateCallback(){ .gJ2P?
publicObject doInHibernate mw
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(Session session)throws HibernateException { cj[b ^Wv:
Criteria criteria = Ks%0!X?3q
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detachedCriteria.getExecutableCriteria(session); t neTOj
int totalCount = )aIcA
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((Integer) criteria.setProjection(Projections.rowCount Wzl/ @CPM
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()).uniqueResult()).intValue(); z;qDl%AF
criteria.setProjection ;MS.ag#
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(null); ^>IP"k F
List items = z)3TB&;
(TT=i
criteria.setFirstResult(startIndex).setMaxResults P-\f-FS
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(pageSize).list(); ]UvB+M]Lv)
PaginationSupport ps = Q>{$Aqc,e
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new PaginationSupport(items, totalCount, pageSize, stRM*.
Q VTL}AT2:
startIndex); Yqs=jTq`{
return ps; :TQp,CEa
} ws0qwv#
}, true); P~\rP6
;
} jSem/;
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public List findAllByCriteria(final w5m/[Z
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DetachedCriteria detachedCriteria){ W[&nQW$E
return(List) getHibernateTemplate layxtECP(
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().execute(new HibernateCallback(){ (K[{X0T
publicObject doInHibernate l?m"o-Gp3
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(Session session)throws HibernateException { 9+1{a.JO
Criteria criteria = g6Vkns4
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detachedCriteria.getExecutableCriteria(session); B[uyr)$
return criteria.list(); lM\dK)p21O
} bsQ'kBD
}, true); HJl?@&l/
} ]KFh 1
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public int getCountByCriteria(final iV{_?f1jo
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DetachedCriteria detachedCriteria){ e4YfJd
Integer count = (Integer) &[d'g0pF
p cLKE
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getHibernateTemplate().execute(new HibernateCallback(){ 31G:[;g
publicObject doInHibernate +~"IF+TRH
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(Session session)throws HibernateException { ,Q"'q0hM=
Criteria criteria = k[x-O?$O@
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detachedCriteria.getExecutableCriteria(session); `:C1Wo^<
return *ra)u-
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criteria.setProjection(Projections.rowCount V>Jr4z
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()).uniqueResult(); N]W*ei
} Nn_fhc>
}, true); gN/!w:
return count.intValue(); Q`bXsH
} 5p.rd0T]l3
} )?72 +X
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用户在web层构造查询条件detachedCriteria,和可选的 (U'n1s/X
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 <Y)14w%
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PaginationSupport的实例ps。 v/ry" W
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ps.getItems()得到已分页好的结果集 ^JY {<
ps.getIndexes()得到分页索引的数组 DGJ:#UE
ps.getTotalCount()得到总结果数 U.TZd"
ps.getStartIndex()当前分页索引 |lLe^FM
ps.getNextIndex()下一页索引 1:eWZ]B5"
ps.getPreviousIndex()上一页索引 =o(}=T>:"
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 /o4_rzR?
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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 s~,!E
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一下代码重构了。 S\Z*7j3;M
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我把原本我的做法也提供出来供大家讨论吧: 4<s;xSCL
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首先,为了实现分页查询,我封装了一个Page类: +vZYuEq_
java代码: E]q>ggeNH
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/*Created on 2005-4-14*/ [
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package org.flyware.util.page; Y's=31G@
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/** 0-p^ oA
* @author Joa Ow-ejo
* lz=DGm
*/ pKLcg"{[F
publicclass Page { W<<G
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/** imply if the page has previous page */ \WE/#To
privateboolean hasPrePage; 0faf4LzU!
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/** imply if the page has next page */ I6WHC*
privateboolean hasNextPage; dtuCA"D
.;?ha'
/** the number of every page */ ,GWa3.&.d
privateint everyPage; v_5O*F7)
)-+tN>Bb
/** the total page number */ 7'+`vt#E
privateint totalPage; kYS#P(1
/;_$:`|/
/** the number of current page */ gB#!g@
privateint currentPage; ${Lrj}93
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/** the begin index of the records by the current >%"TrAt
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query */ {X,-T&
privateint beginIndex; Rq15AR
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/** The default constructor */ #p"F$@N
public Page(){ o< b
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} fwtsr>SV
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/** construct the page by everyPage :V8oWMY
* @param everyPage :TrP3wV_
* */ '\H
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public Page(int everyPage){ >a@1y8B
this.everyPage = everyPage; uYTyR;a
} =2Ju)!%wr
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/** The whole constructor */ 34k(:]56|
public Page(boolean hasPrePage, boolean hasNextPage, :qXREF@h
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7
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int everyPage, int totalPage, j.Y!E<e4]
int currentPage, int beginIndex){ O0^Y1l
this.hasPrePage = hasPrePage; 1|*%
this.hasNextPage = hasNextPage; t":^:i'M
this.everyPage = everyPage; [9EL[}
this.totalPage = totalPage; #~*v*F~3
this.currentPage = currentPage; =]Y'xzJuu
this.beginIndex = beginIndex; D{]w+
} :^7_E&
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/** 6mZpyt
* @return 2QHu8mFU
* Returns the beginIndex. a"O9;&};&
*/ g7%vI8Y)@
publicint getBeginIndex(){ ;rJ#>7K
return beginIndex; OwC{ Ad{
} 'e))i#/VF
w#(E+s~}
/** 9MRe?
* @param beginIndex {KqW<X6Hp
* The beginIndex to set. ld~*w
*/ 5k_%%><: q
publicvoid setBeginIndex(int beginIndex){ IL8&MA%
this.beginIndex = beginIndex; w4y???90)
} 4>=Y@z
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/** DKQQZ`PF
* @return 0} \;R5a<
* Returns the currentPage. 1
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*/ G* mLb1
publicint getCurrentPage(){ o,1Fzdh6(
return currentPage; uN9.U _
} 0J )VEMC
P`hg*"<V
/** $I@. <J*
* @param currentPage x@@k_'~t%
* The currentPage to set. e]jzFm~
*/ BGB.SN#q+
publicvoid setCurrentPage(int currentPage){ Re\V<\$J
this.currentPage = currentPage; %]DJ-7 xE
} )N
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/** ctC!b{S"@
* @return kZ_5R#xK
* Returns the everyPage. ~o;*{ Q
*/ YF");itH
publicint getEveryPage(){ eR1]<Z$W\
return everyPage; =uR[Jewa
} a67NWH
Xo4K!U>TzZ
/** fl9J
* @param everyPage N'5!4JUI
* The everyPage to set. M\9p-%"L
*/ oX]c$<w5
publicvoid setEveryPage(int everyPage){ X15e~;&
this.everyPage = everyPage; u|8V7*)3
} zQ eXN7$
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/** $
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* @return CI?M2\<g
* Returns the hasNextPage. D #twS
*/ I'uRXvEr7
publicboolean getHasNextPage(){
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return hasNextPage; 8J7<7Sx
} d 'wWj
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/** s2+s1%^Ll
* @param hasNextPage H"g
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* The hasNextPage to set. ,e>N9\*
*/ (OK;*ZH+T@
publicvoid setHasNextPage(boolean hasNextPage){ G0h7MO%x
this.hasNextPage = hasNextPage; blB00
} 4[]4KKO3Q2
@xtfm.}
/** au1(.(
* @return C@
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* Returns the hasPrePage. \xaK?_hv
*/ g*#.yC1/
publicboolean getHasPrePage(){ gTP0:
return hasPrePage; aq,?
} RnkrI~x
xBcE>^{1.
/** X6@G)68
* @param hasPrePage Ik|nL#JH]
* The hasPrePage to set. E>SLR8!Cv
*/ ?g'? Ou
publicvoid setHasPrePage(boolean hasPrePage){ *e05{C:kS
this.hasPrePage = hasPrePage; "(d7:!%
} -z4pI=
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/** *]
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* @return Returns the totalPage. rfMzHY}%
* MY}B)`yx=
*/ Ey;uaqt
publicint getTotalPage(){ 7l3sd5
return totalPage; n P4DHb&5
} dAcy;-[[P
',p`B-dw
/** 5zF7yvS.w
* @param totalPage vJfex,#lv
* The totalPage to set. t1YVE%`w
*/ /g!', r,
publicvoid setTotalPage(int totalPage){ =sW(2Im
this.totalPage = totalPage; e'z[JG=
} wg=ge]E5
beYaQz/@W
} %<8lLRl
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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 h>+,ba"D
5l"v:Px
个PageUtil,负责对Page对象进行构造: /u8m|S<
java代码: #}W^d^-5t5
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/*Created on 2005-4-14*/ 0)'^vJe
package org.flyware.util.page; <k&Q"X:"
}Z_w8+BZ
import org.apache.commons.logging.Log; N?h=Zl|
import org.apache.commons.logging.LogFactory; 1^zpO~@S
Vn6 g(:\w
/** b}9Ry"
* @author Joa m. G}#/
* 1/YWDxo,
*/ bi bjFg
publicclass PageUtil { -q BrJ1*
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privatestaticfinal Log logger = LogFactory.getLog E8~Bp-G)
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(PageUtil.class); 39QAj&
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/** 8rXu^
* Use the origin page to create a new page H1>}E5^?
* @param page ~ b;%J:
* @param totalRecords v'*#P7%Kf
* @return g,!6,v@
*/ 1#9 Q1@'OS
publicstatic Page createPage(Page page, int MGd 7Ont
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totalRecords){ nxP>IfSA
return createPage(page.getEveryPage(), 9air"4
^6 F-H(
page.getCurrentPage(), totalRecords); `2y2Bk
} brGUK PB
([='LyH];z
/** jd|? aK;(
* the basic page utils not including exception 0S0 ?\r
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handler +.T&U7xV
* @param everyPage `)FSJV1
* @param currentPage "]81+
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* @param totalRecords HgP9evz,0
* @return page oq4*m[
*/ vcnUb$%
publicstatic Page createPage(int everyPage, int k1HukGa
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currentPage, int totalRecords){ ++Qg5FukR
everyPage = getEveryPage(everyPage); Cyg\FHs
currentPage = getCurrentPage(currentPage); WUSkN;idVG
int beginIndex = getBeginIndex(everyPage, hTZaI *
pDO&I]S`q0
currentPage); (5] |Kcp|
int totalPage = getTotalPage(everyPage, jemg#GB8
q"@Y2lhD!
totalRecords); E-_FxBw
boolean hasNextPage = hasNextPage(currentPage, mYf7?I~
wIIxs_2Q0c
totalPage); r<38; a
boolean hasPrePage = hasPrePage(currentPage); 7yLO<o?9w
j_VTa/
returnnew Page(hasPrePage, hasNextPage, xJ)hGPrAl
everyPage, totalPage, y|1,h}H^n
currentPage, (-tF=wR,W
\e64Us>"x
beginIndex); 00 Qn1
} p=vu<xXtD
FWv-_
privatestaticint getEveryPage(int everyPage){ )>$@cH
return everyPage == 0 ? 10 : everyPage; <o8j+G)K#
} ^b=9{.5
j'#M'W3@
privatestaticint getCurrentPage(int currentPage){ FOxMt;|M
return currentPage == 0 ? 1 : currentPage; sHx>UvN6
} pJ7M.C!
."<mL}Fi(
privatestaticint getBeginIndex(int everyPage, int vkWh2z
s)ymm7?
currentPage){ 7{
zkqug
return(currentPage - 1) * everyPage; 5_@ u Be~
} sBGYgBu!a
Ly1V@
privatestaticint getTotalPage(int everyPage, int oqa]iBO
E(F<shT#
totalRecords){ y#Je%tAe
2
int totalPage = 0; g/&`NlD
6\ g-KO
if(totalRecords % everyPage == 0) 2`qO'V3Q
totalPage = totalRecords / everyPage; Zb<IZ)i# 1
else XS5*=hv:
totalPage = totalRecords / everyPage + 1 ; G:NI+E"]
bLyU;
return totalPage; e)kN%JqW
} ]5X=u(}
#;59THdtPk
privatestaticboolean hasPrePage(int currentPage){ <QoSq'g#,=
return currentPage == 1 ? false : true; #gzY _)E
} [;3` Aw
jdsN ZV
privatestaticboolean hasNextPage(int currentPage, AV\6K;~
^sR]w]cz.
int totalPage){ Nf(Np1?;c
return currentPage == totalPage || totalPage == !iBe/yb
Sq"O<FmI
0 ? false : true; *5'U3py
} cs[_5r&:
,2\?kPoc8
Te=[tx~x
} e|)6zh<O:
>CtT_yhx
C'mYR3?m;
5}d"nx
gPs%v`y)*D
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。 vovc,4}
7'g'qUW+~
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 by z2u
S&]AIG)
做法如下: Wy{xTLXk2
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 *"4d6
dLb9p"EE#
的信息,和一个结果集List: \mRRx#-r%
java代码: n]$50_@
#w\Bc\
d4OWnPHv&}
/*Created on 2005-6-13*/ ck-ab0n
package com.adt.bo; @Sb 86Ee
*k)v#;B
import java.util.List; zs!}P
Id`?yt
import org.flyware.util.page.Page; |_q:0qo
: tKa1vL
/** h/u>F$}c
* @author Joa NjT#p8d X
*/ ts
BPQ 8Ne
publicclass Result { "RPX_
VJ1(|v{D4[
private Page page; KUs\7Sb
hs'J'~a
private List content; .kO!8Q-;%
7O6VnKl
/** N\ nr
* The default constructor -:92<G\D
*/ '\yp}r'u
public Result(){ '_)NI
super(); Hd)z[6u8eT
} 3m1]Ia-9
!FwR7`i
/** fJ"#c<n
* The constructor using fields -&87nR(eW
* B{IYVviiP
* @param page !Gwf"-TQ
* @param content }2qmL$
*/ Yv0;U Kd
public Result(Page page, List content){ = ~{n-rMF
this.page = page; WH Zz?|^
this.content = content; yxfV|ox
} _ PC}`Y'&
PVBf'
/** 1S!<D)n
* @return Returns the content. U'IJwGRP
*/ G/tah@N[7
publicList getContent(){ /rRQ*m_
return content; bJ8~/d]+
} 9:tvkl
FS.z lk\D=
/** J:M)gh~#
* @return Returns the page. XxT7YCi
*/ (`0dO8
public Page getPage(){ ;1Kxqpz_i
return page; s(yV E
} =6#tJgg8
<,S0C\la=
/** pa0'\
* @param content
.*H0{
* The content to set. :P$I;YY=A
*/ ypxqW8Xe
public void setContent(List content){ phIEz3Fu/
this.content = content; kqYvd]ss
} Nkfu k
s^_E'j$
/** 5BKmp-m
* @param page zdA:K25"
* The page to set. M4a-+T"
*/ f[)_=T+
publicvoid setPage(Page page){ l'~]8Wo1
this.page = page; Y=3:Q%X
} !=#230Y
} I>b-w;cC
LkFXUt ?
ZyqTtA!A
aE^tc'h~
4%WV)lt
2. 编写业务逻辑接口,并实现它(UserManager, D5X;hd
Y^gK^?K
UserManagerImpl) H[ %Fo
java代码:
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l79jd%/m
"r0z(j
/*Created on 2005-7-15*/ o a,Ju
package com.adt.service; 78tWzO
>Uvtsj#
import net.sf.hibernate.HibernateException; {+[~;ISL
%+$P<Rw7
import org.flyware.util.page.Page; xmtbSRgK9
r
@~T}<I
import com.adt.bo.Result; -"5x? \.{m
o}5:vi]
/** Yfy6o6*:
* @author Joa 8xmw-s)
*/ #&">x7?5
publicinterface UserManager { $P]%Px!x
HSx~Fs^J
public Result listUser(Page page)throws c1/Gyq
Sm#;fx+
HibernateException; vII&v+C
U-TwrX
} H<`[,t
*Rshzv[
*MkhRLw\,
w;Qo9=-
qce#
java代码: 8 Oeg"d
TMG:fg&E~
C5Q|3d
/*Created on 2005-7-15*/ #I@]8U#,":
package com.adt.service.impl; ( ~pcPGUG
8{Y
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import java.util.List; }M/w 0U0o
o<-%)#e
import net.sf.hibernate.HibernateException; #s1M>M)
;JFE7\-mC
import org.flyware.util.page.Page; NpD}7t<EF
import org.flyware.util.page.PageUtil; 'KQ]7
W<2%J)N<
import com.adt.bo.Result; uYL6g:]+ZC
import com.adt.dao.UserDAO; )F? 57eh
import com.adt.exception.ObjectNotFoundException; P0Na<)\'Y!
import com.adt.service.UserManager; !N,Z3p>Q
5 LX3.
/** z$G?J+?J
* @author Joa p%IR4f
*/ >^:g[6Sj
publicclass UserManagerImpl implements UserManager { D4'?
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private UserDAO userDAO; 0P/A
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he
/** ~B(]0:
* @param userDAO The userDAO to set. d5A!kU _.
*/ Z;S*fS-_
publicvoid setUserDAO(UserDAO userDAO){ Z/wh?K3y
this.userDAO = userDAO; Dr`\
} &t%CuU]/@
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/* (non-Javadoc) `1EBnL_1
* @see com.adt.service.UserManager#listUser 1`O`!plD+
[tMf KO
(org.flyware.util.page.Page) |@nvg>mu
*/ RW(AjDM
public Result listUser(Page page)throws RU"w|Qu>pM
JIb<>X,
HibernateException, ObjectNotFoundException { Pms3X
int totalRecords = userDAO.getUserCount(); xOT'4v&.
if(totalRecords == 0) xxkP4,(p
throw new ObjectNotFoundException *`}_e)(k
2+=|!+f
("userNotExist"); HC{|D>x.
page = PageUtil.createPage(page, totalRecords); />ob*sk/Y
List users = userDAO.getUserByPage(page); .?I!/;=[
returnnew Result(page, users); iZMsN*9[
} #-'}r}1ZT
|B` -chK
} 'EZ[aY!);
EE}NA{b
}#'KME4
8@hzw~>
LOnhFX
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 MCh8Q|Yx4
8~HC0o\2
询,接下来编写UserDAO的代码: b V9Z[[\
3. UserDAO 和 UserDAOImpl: Ysr{1! K
java代码: B10p7+NBF
)sV#
b
TdKl`"Iy
/*Created on 2005-7-15*/ h*MR5qa
package com.adt.dao; "[[fQpe4@
e982IP
import java.util.List; nrt0[E-&~
l42m81x"
import org.flyware.util.page.Page; yFpHRfF}
w|L~+
import net.sf.hibernate.HibernateException; !'{j"tv
rB4#}+Uq
/** .qK=lHxT
* @author Joa ?>%u[g
*/ k5/nAaiVE
publicinterface UserDAO extends BaseDAO { %+I(S`}
k2t?e:)3zr
publicList getUserByName(String name)throws *0c
}`|
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HibernateException; JA(nDD/;
MxdfuFss
publicint getUserCount()throws HibernateException; v,D_^?] @
|nicvg@
publicList getUserByPage(Page page)throws (VO Ka
mlVv3mVyR<
HibernateException; 8fe"#^"s R
g u|;C
} _O!D*=I
>}4]51s
) F~>
[CUJ A
?1N0+OW
java代码: y:42H tS
'^/E2+
Bw_Ih|y,w
/*Created on 2005-7-15*/ ]~K&mNo
package com.adt.dao.impl; %eV`};9
!8L
Ql}
import java.util.List; L}21[ N~ky
&R5M&IwL
import org.flyware.util.page.Page; 3?O|X+$p
:?UIyN?
import net.sf.hibernate.HibernateException; zHdp'J"
import net.sf.hibernate.Query; D46|)-
d|o"QYX
import com.adt.dao.UserDAO; jSVO$AW~C
?s?uoZ /2
/** QE #$bCw
* @author Joa =TP>Y"
*/ (Dl"s`UH~
public class UserDAOImpl extends BaseDAOHibernateImpl 6AwnmGL(;;
w-#0k.T
implements UserDAO { H9>&"=".
A N%.LK
/* (non-Javadoc) 2ga}d5lu
* @see com.adt.dao.UserDAO#getUserByName RyhR#
xg^fM@#m
(java.lang.String) b@X@5SJFW
*/ YpKai3 B
publicList getUserByName(String name)throws d#d~t[=
E{6}'FG+A
HibernateException { u]2k %TUY
String querySentence = "FROM user in class [.Y=~)7FB
ho20>vw#
com.adt.po.User WHERE user.name=:name"; !6%G%ZG@3-
Query query = getSession().createQuery GawO>7w8
c:6w >:
(querySentence); qnS7z%H8
query.setParameter("name", name); IY19G U9
return query.list(); Kulg84<AwM
} B.G!7>=
?oJ~3Kg
/* (non-Javadoc) 5&kR1Bp#-
* @see com.adt.dao.UserDAO#getUserCount() #
R&[+1=9j
*/ Yq
Fzbm{\
publicint getUserCount()throws HibernateException { d5=xOEv;
:
int count = 0; 6wd]X-G++
String querySentence = "SELECT count(*) FROM y?JbJ
yJL"uleRT
user in class com.adt.po.User"; p)jxqg
Query query = getSession().createQuery AFFLnLA<L
}M7kApb>Y
(querySentence); Sy'>JHx
count = ((Integer)query.iterate().next dJ!o/y6
8$vH&HdI
()).intValue(); C5M-MZaS
return count; H<xC%/8
} -,;Ep'
<^\r9Qxl
/* (non-Javadoc) l
xfdJNb
* @see com.adt.dao.UserDAO#getUserByPage #TWc` 8
nGbrWu]w
(org.flyware.util.page.Page) sy?>e*-{
*/ !kcg#+s91
publicList getUserByPage(Page page)throws .'a |St
mr1}e
VM~!
HibernateException { y|dXxd9
String querySentence = "FROM user in class mqHt%RX
xS}H483h6W
com.adt.po.User"; nKO&ffb'<
Query query = getSession().createQuery _+N^yw ,r*
Pc7:hu
(querySentence); p~.@8r(
query.setFirstResult(page.getBeginIndex()) <e^/hR4O
.setMaxResults(page.getEveryPage()); DPwSg\*)
return query.list(); #'8PFw\zw
} `Z/ IW
9CNHjs+-}s
} K_5&_P1
IebS~N
E
5);#\&B
J qUVGEg
e%U*~{m+
至此,一个完整的分页程序完成。前台的只需要调用 .vv*bx
8j'*IRj*q
userManager.listUser(page)即可得到一个Page对象和结果集对象 6.|~~/
LU{Z
的综合体,而传入的参数page对象则可以由前台传入,如果用 ]~^/w}(K
8UIL_nPO
webwork,甚至可以直接在配置文件中指定。 =5ih,>>g
4I-p/&Q
下面给出一个webwork调用示例: //Gvk|O1
java代码: O i0;.<kX
_@N)]!\MgP
dM UDLr-
/*Created on 2005-6-17*/ `X='g96C1
package com.adt.action.user; tD]&et
32iI :u
import java.util.List; JF*g!sV%
UTQKlwPa
import org.apache.commons.logging.Log; HD{`w1vcN
import org.apache.commons.logging.LogFactory; k&/)g3(N(
import org.flyware.util.page.Page; IDh`0/i]
Zir`IQ$
import com.adt.bo.Result; (UF!Zb]{
import com.adt.service.UserService; Gme$FWa
import com.opensymphony.xwork.Action; DANSexW
GC[{=]}9U
/** .$0Ob<.
* @author Joa bUN,P"
*/ @q/1m~t
publicclass ListUser implementsAction{ pK9^WT@
2 ?T:RB}
privatestaticfinal Log logger = LogFactory.getLog X u):.0I
dz|*n'd
(ListUser.class); pq3 A%|
wzPw;xuG
private UserService userService; i grog
Yp]G)}'R
private Page page; Pp_3 nyQ
nb_^3K]r
privateList users; 2<G1'7)
q|X4[E|{Q
/* Qc;[mxQe
* (non-Javadoc) `4H9f&8(
* &H&P)Px*_
* @see com.opensymphony.xwork.Action#execute() k|3(dXLG
*/ o#P3lz
publicString execute()throwsException{ {p|%hhTK%
Result result = userService.listUser(page); 50ew/fZj|
page = result.getPage(); aNC,ccm
users = result.getContent(); :bRR(sP
return SUCCESS; Kk>qgi$
} 5\0.[W{^
_IV@^v
/** )v=G}j^
* @return Returns the page. cXcx_-
*/ (VaN\+I:T
public Page getPage(){ RVnyl`s
return page; h+3Z.WKhwP
} `4.sy +2
KWJgW{{v
/** (oitCIV
* @return Returns the users. rz}l<t~H
*/ 0BB@E(*
publicList getUsers(){ rm=~^eB
return users; :{s%=\k {d
} {!1n5a3" 1
X$ B]P7G7
/** k!/_/^{
* @param page 1Bk*G>CX9(
* The page to set. @zynqh
*/ a\69,%!:
publicvoid setPage(Page page){ S"^KJUUc
this.page = page; @B'8SLoP
} bsi q9$F
@'r`(o3z!Z
/** Ui|a}`c
* @param users Z;y}gv/{
* The users to set. 3y=<w|4F
*/ y8hg8J|
publicvoid setUsers(List users){
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this.users = users; StZRc\k
} X;6r$
to!W={S<ol
/** {QS@Ugf
* @param userService Pkx(M E
* The userService to set. {,f!'i&b@
*/ v^],loi<V
publicvoid setUserService(UserService userService){ \+Rwm:lI
this.userService = userService; qi SEnRG.
} Gr#rM/AfCK
} ZC5Yve8
^s@*ISY
:uwRuPI
mrhp)yF
@oz&
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, 22/?JWL>
6Sb'Otw.
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 Ef`5fgp?
S
sK 1m9
么只需要: [B~zoB(
java代码: L.0} UXd
:Q
r7:$S^
P"=UI$HN
<?xml version="1.0"?> bN4&\d*u#
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork 7 xp1\j0
)YnI!v2T
1.0//EN" "http://www.opensymphony.com/xwork/xwork- @x=BJuUuX
bmO__1
1.0.dtd"> 3KG) 6)1*
K_&c5(-(_
<xwork> A:.IBctsd
YoF\MT]W
<package name="user" extends="webwork- 1>@]@ST[:
38U5^`
interceptors"> )pS_+ZF
V^ fGRA
<!-- The default interceptor stack name @r/Id{pCI
8XYD
L]I'
--> ?BDlB0jxzi
<default-interceptor-ref XY!{ g(
_
7BF+*T
name="myDefaultWebStack"/> nG},v%
:n+y/6*
<action name="listUser" B15O,sL&W
@7Rt4}g
class="com.adt.action.user.ListUser"> vzyN c'
<param !qTpQ5Dm
7TV>6i+7
name="page.everyPage">10</param> EFRZ% Y
<result B;z>Dd,Y_x
#0?"J)
name="success">/user/user_list.jsp</result> 8g[(nxI~
</action> Ho )t=qn
&N/|(<CB
</package> C`2*2Y%xkG
'z +$3\5L
</xwork> ez^*M:K
B_."?*|w
BP[CR1Gs
N;C"X4rV
@Z9>3'2]A
3^02fy
这样就可以通过配置文件和OGNL的共同作用来对page对象设置初值 FI?gT
%Ye)8+-
了。并可以通过随意修改配置文件来修改每页需要显示的记录数。 b:F Ep'ZS
ot@|blVC8
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 3@PUg(M
+p9LE4g7Q
U^[cYTG
lruF96C/Y
VQy9Y
我写的一个用于分页的类,用了泛型了,hoho M.xhVgFf)
Hi; K"H]x1
java代码: OX)#F'Sl}
N+\oFbE
`7QvwXsH]
package com.intokr.util; ~^lH ^J
4i_spF-3
import java.util.List; .Bb$j=
9?u9wuH
/** i"%JFj_G
* 用于分页的类<br> uQ[vgNe*m
* 可以用于传递查询的结果也可以用于传送查询的参数<br> ,zAK3d&hj
* bU;}!iVc]
* @version 0.01 Mvy6"Q:
* @author cheng LN@E\wRw{r
*/ aW0u8Dz
public class Paginator<E> { RNv{n
mf
privateint count = 0; // 总记录数 Iz6ss(UJ
privateint p = 1; // 页编号 U8-Q'1IT&
privateint num = 20; // 每页的记录数 j>$=SMc
privateList<E> results = null; // 结果 pau*kMu^}
tJUVw=
/** {E3xI2
* 结果总数 Ne &Xf
*/ %^a]J"Ydi8
publicint getCount(){ y2z{rd
return count; qpb/g6g
} cm@jt\D
i{TIm}_\
publicvoid setCount(int count){ bK?1MiXb
this.count = count; Y
brx%
} @T<ad7g-2J
A#v|@sul
/** q%OcLZ<,
* 本结果所在的页码,从1开始 4t&gW
* >EBZ$ X
* @return Returns the pageNo. WW//heJe-
*/ [3t0M5x w
publicint getP(){ Dh
hG$
return p; '8s>rH5[V
} d>lt
+<S9E'gT3V
/** Wc~3^;U
* if(p<=0) p=1 &?SX4c~?u
* J+{Ou rWt
* @param p 8K|J:[7
*/ lbQ6
a
publicvoid setP(int p){ AI&qU/}
if(p <= 0) \bU`
p = 1; Qo'yS"g<9)
this.p = p; ! G*&4V3Mg
} 1S+;ZMk
>F/XZC
/** f"vk# 3
* 每页记录数量 v2Dt3$@H6
*/ uzHT.iBn
publicint getNum(){ YSqv86
return num; *,"jF!C&[
} By2s ']bw
7sXy`+TZ->
/** j'3j}G%\T
* if(num<1) num=1 ec`bz "1
*/ ,%A)"doaG
publicvoid setNum(int num){ bRWIDPh
if(num < 1) Dq?E\
num = 1; X6Un;UL
this.num = num; p`d
XqW
} 2Oyy`k
@'*eC}\E
/** I`22Zwq:
* 获得总页数 T36x=LX
*/ 8QT<M]N%
publicint getPageNum(){ St6aYK
return(count - 1) / num + 1; C`dkD0_
} ( :
A'GlCp
/** 5gSylts8
* 获得本页的开始编号,为 (p-1)*num+1 34z_+
*/ "\7 v
publicint getStart(){ G@9u:\[l
return(p - 1) * num + 1; 5B1G?`]?
} NeHx2m+
BYS lKTh
/** P^"R4T
* @return Returns the results. M ~als3
*/ RoX
&+~
publicList<E> getResults(){ RL6Vkd?
return results; 4AQ[igTDP
} auRY|j
/-Wuq`P/ T
public void setResults(List<E> results){ "lTZ|k^
this.results = results; 'qjX$]H
} W]_g4,T>
rOW;yJ[
public String toString(){ Kv}k*A% S
StringBuilder buff = new StringBuilder %MN.O-Lc
U2bzUxK
(); S`=n&'
buff.append("{"); hd5$ yU5JQ
buff.append("count:").append(count); IhE9snJ[
buff.append(",p:").append(p); (VyA6a8
buff.append(",nump:").append(num); T'.[F
buff.append(",results:").append
rIVvO
)Ob]T{GY
(results); X'f)7RbT
buff.append("}"); \b$<J.3
return buff.toString(); 5X0QxnnV
} W"Z#Fs{n8
'G8 ?'u_)
} ,HZYG4,
za T_d/?J
1fY>>*oP