Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 f~-Ipq;F
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 KOYcT'J@vR
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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 mZ!1Vh
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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 4PDxmH]y
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分页支持类: 79G& 0 P\
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java代码: Izr_]%
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package com.javaeye.common.util; Lju)q6
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import java.util.List; P8\bi"iiN
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publicclass PaginationSupport { 5* 3T+OK
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publicfinalstaticint PAGESIZE = 30; l6z}D;4
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privateint pageSize = PAGESIZE; x2@W,?oPm
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privateList items; bS"zp6Di
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privateint totalCount; kHx6]<
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privateint[] indexes = newint[0]; 5FQtlB9F
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privateint startIndex = 0; S*9qpes-m|
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public PaginationSupport(List items, int e%K
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totalCount){ H=1Jq
setPageSize(PAGESIZE); 5A`T}~"X
setTotalCount(totalCount);
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setItems(items); C[IY9s:Pf
setStartIndex(0); gkRbb
} #dEMjD
&* 1iW(x
public PaginationSupport(List items, int ^!yJ;'H\
} Rs@
totalCount, int startIndex){ l?J|Ip2W
setPageSize(PAGESIZE); WIkr0k
setTotalCount(totalCount); D
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setItems(items); V+- ]txu|
setStartIndex(startIndex); ON
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} *Iir/6myM
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public PaginationSupport(List items, int #s]'2O
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totalCount, int pageSize, int startIndex){ %K7wScz7
setPageSize(pageSize); X$(Dem
setTotalCount(totalCount); D5gDVulsh
setItems(items); $Q'S8TU
setStartIndex(startIndex); p|,3X*-ynx
} N&K`bmtD
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publicList getItems(){ *CS2ndp
return items; ]46#u=y~3
} k<i#agq
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publicvoid setItems(List items){ u>-pgu
this.items = items; f\]splL
} 6&KvT2?tA`
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publicint getPageSize(){ 1$1[6
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return pageSize; 22_%u=p-|
} Q( g&/O
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publicvoid setPageSize(int pageSize){ 71(C@/J
this.pageSize = pageSize; Z(0sMOaX
} GiGXV @dq
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publicint getTotalCount(){ w(-h!d51+
return totalCount; 7v{s?h->$
} \;F_QV
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publicvoid setTotalCount(int totalCount){ t~(|2nTO5
if(totalCount > 0){ D/x!`&.sN
this.totalCount = totalCount; zc#$hIi
int count = totalCount / DSX.84
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pageSize; .QVZ!
if(totalCount % pageSize > 0) "B"Yfg[
count++; ( {}Z
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indexes = newint[count]; xG"*w@fs7
for(int i = 0; i < count; i++){ 8{ooLdpX7
indexes = pageSize * 6(as.U>K
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i; gSn9L)k(O
} =/zb$d cz
}else{ &w"1VOV<
this.totalCount = 0; lwj,8
} LzE$z,
} ;.EW7`)Z
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publicint[] getIndexes(){ ~+OAAkJ9
return indexes; tQSJ"Q
} (#?k|e"Y"`
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publicvoid setIndexes(int[] indexes){ R m^$Dn
this.indexes = indexes; ecIZ+G)k
} & Y Y^Bd#
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publicint getStartIndex(){ _j Ck)3KO
return startIndex; >.4mAO
} \!Cc[n(f#
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publicvoid setStartIndex(int startIndex){ >xB[k-C4
if(totalCount <= 0) vn"+x_
this.startIndex = 0; yuA+YZ
elseif(startIndex >= totalCount) TcEvUZJ"
this.startIndex = indexes x_VD9
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[indexes.length - 1]; 14Y<-OO:
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elseif(startIndex < 0) @B#\3WNt
this.startIndex = 0; OJ!=xTU%h
else{ sfKu7p uc
this.startIndex = indexes O}w"@gO@.
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[startIndex / pageSize]; "J(0J
} D6L5X/#
} r=74'g
97 eEqI$#
publicint getNextIndex(){ *3Qwmom
int nextIndex = getStartIndex() + 2/F";tc\'
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pageSize; B/F6WQdZ
if(nextIndex >= totalCount) vnr{Ekg
return getStartIndex(); F)n^pT
else ::`#qa4!
return nextIndex; J<;@RK,c_
} 0s'h2={iI
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publicint getPreviousIndex(){ ]:_s7v
int previousIndex = getStartIndex() - 7H!/et?S,
,*MAteD
pageSize; !> 2kH
if(previousIndex < 0) *l{GD1ZDk
return0; EJ@&vuDd$
else I 6-.;)McO
return previousIndex; s{9G//
} =IH~:D\&
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} ?%A9}"q]
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抽象业务类 #T3dfVWv
java代码: ;k|U2ajFJ
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/** <{P`A%g@
* Created on 2005-7-12 'B\7P*L"p
*/ Q&]f9j_
package com.javaeye.common.business; (|9t+KP
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import java.io.Serializable; 5_7y 1
import java.util.List; J~.`
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import org.hibernate.Criteria; \)`OEGdOR\
import org.hibernate.HibernateException; K;Fs5|gFU
import org.hibernate.Session; 6m%#cP
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import org.hibernate.criterion.DetachedCriteria; z3Zo64V~7
import org.hibernate.criterion.Projections; Zk ] /m
import ?>s[B7wMp
r#'ug^^k$X
org.springframework.orm.hibernate3.HibernateCallback; e|}B;<
import
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org.springframework.orm.hibernate3.support.HibernateDaoS ^D8~s; ?
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upport; D/YMovH%
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import com.javaeye.common.util.PaginationSupport; oJ?,X^~_
\IaUsx"#o{
public abstract class AbstractManager extends 19b@QgfWpb
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HibernateDaoSupport { jS ?#c+9
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privateboolean cacheQueries = false; v`@M IOv
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privateString queryCacheRegion; fE"-W{M
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publicvoid setCacheQueries(boolean AO238RC!:
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cacheQueries){ )G),iy
this.cacheQueries = cacheQueries; v{SZ(;
} ]P/i}R:
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publicvoid setQueryCacheRegion(String 2m^qXE$
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queryCacheRegion){ fjCFJ_
this.queryCacheRegion = [,3E#+y
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queryCacheRegion; 21O@yNpS$
} D"gv:RojD
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publicvoid save(finalObject entity){ f0879(,i
getHibernateTemplate().save(entity); 2@W`OW Njm
} RzU9]e
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publicvoid persist(finalObject entity){ ^5Zka!'X2Z
getHibernateTemplate().save(entity); K~4bT=
} Y-lwS-Ii
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publicvoid update(finalObject entity){ aLl=L_
getHibernateTemplate().update(entity); !mmSF1f
} pk`5RDBu
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publicvoid delete(finalObject entity){ ]ddH>y&o
getHibernateTemplate().delete(entity); WcQkeh3n
} 0{
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publicObject load(finalClass entity, 4
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finalSerializable id){ PjofW%7F
return getHibernateTemplate().load -(7oFOtg
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(entity, id); 3xN_z?Rg
} I5)$M{#a
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publicObject get(finalClass entity, UoaWI2
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finalSerializable id){ X,c`,B03
return getHibernateTemplate().get U_hzSf
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(entity, id); }u8g7Nj
} B`gH({U
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publicList findAll(finalClass entity){ :wEy""*N0
return getHibernateTemplate().find("from 8)MWC:
&-w. rF@
" + entity.getName()); unNN&m#@
} C4GkFD
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publicList findByNamedQuery(finalString #
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namedQuery){ oIQ$98 M
return getHibernateTemplate acgx')!c
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().findByNamedQuery(namedQuery); 6$kh5$[
} 2G<XA
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publicList findByNamedQuery(finalString query, sl"H!cwF
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finalObject parameter){ pe>?m ^gz[
return getHibernateTemplate \j-:5M#m
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().findByNamedQuery(query, parameter); vR>GE?s6
} u.*}'C>^^v
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publicList findByNamedQuery(finalString query, OT$++cj^
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finalObject[] parameters){ CJDNS21m
return getHibernateTemplate :Rnwyj])
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().findByNamedQuery(query, parameters); <r(D\rmD
} +WKN&@
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publicList find(finalString query){ V#+F*w?&D
return getHibernateTemplate().find .,U4 ATO
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(query); [@B!N+P5;
} yjq|8.L[
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publicList find(finalString query, finalObject FQE(qltf,
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parameter){ VR%*8=
return getHibernateTemplate().find 1)qD)E5&cf
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(query, parameter); 0%Y}CDn_
} "q!*RO'a
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public PaginationSupport findPageByCriteria TJ>1?W\Z
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(final DetachedCriteria detachedCriteria){ Sfp-ns32%A
return findPageByCriteria U.b|3E/^
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); R~|(]#com
} l<<9H-O
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public PaginationSupport findPageByCriteria hN\sC9a1
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(final DetachedCriteria detachedCriteria, finalint TZ3gJ6 Cb
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startIndex){ .7:ecFKk
return findPageByCriteria Fu\#:+5\
p,uM)LD
(detachedCriteria, PaginationSupport.PAGESIZE,
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startIndex); 9C7HL;MF
} t]iKU@3
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public PaginationSupport findPageByCriteria tB4yj_ZF
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(final DetachedCriteria detachedCriteria, finalint gS`Z>+V5!c
"(kiMog-
pageSize, .|TF /b]
finalint startIndex){ [Ls%nz|
return(PaginationSupport) Ex@}x#3
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getHibernateTemplate().execute(new HibernateCallback(){ gw%L M7yQR
publicObject doInHibernate St>
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(Session session)throws HibernateException { T!pZj_ h=
Criteria criteria = N pQOLX/<?
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detachedCriteria.getExecutableCriteria(session); `krVfE;_O
int totalCount = E @Rb+8},"
}#Iqq9[
((Integer) criteria.setProjection(Projections.rowCount e eyZ$n
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()).uniqueResult()).intValue(); H`Zg-j`
criteria.setProjection 9 }42s +
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(null); k)y<iHR_o
List items = |?MD>Pez
[ :Sl~
criteria.setFirstResult(startIndex).setMaxResults -lq`EB+
}g|9P SbJ
(pageSize).list(); "-AFWWKtx
PaginationSupport ps = O#>,vf$
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new PaginationSupport(items, totalCount, pageSize, G
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startIndex); ?[WUix;
return ps; -rHqU|
} 3Q )"
}, true); 1:./f|m
}
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public List findAllByCriteria(final &g0r#K
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DetachedCriteria detachedCriteria){ b.}J'?yLm
return(List) getHibernateTemplate /c4$m3?]
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().execute(new HibernateCallback(){ (l(d0g&p>
publicObject doInHibernate Pi,86?
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(Session session)throws HibernateException { x8wsx
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Criteria criteria = uBC#4cX`D*
1 .o0"
detachedCriteria.getExecutableCriteria(session); Eq8:[o
return criteria.list(); XB:E<I'q!3
} ]!/R tt
}, true); 0U#m7j
} /N./l4D1K-
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public int getCountByCriteria(final J'L6^-gV
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DetachedCriteria detachedCriteria){ Q#&6J =}
Integer count = (Integer) g"g3|$#Ej|
e. E$Ej]w
getHibernateTemplate().execute(new HibernateCallback(){ P$@:T[}v
publicObject doInHibernate n*#HokX
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(Session session)throws HibernateException { xsvJjs;=
Criteria criteria = yD0DPtti
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detachedCriteria.getExecutableCriteria(session); ZK<c(,oZ^
return
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criteria.setProjection(Projections.rowCount azRp4~2?
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()).uniqueResult(); ItZ*$I1<
} `+0P0(bn
}, true); SR<W3a\
return count.intValue(); qmNG|U&
} ="AaC!E,W
} N~?(<DyZR
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用户在web层构造查询条件detachedCriteria,和可选的 '+*'sQvH[
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 _d>{Hz2
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PaginationSupport的实例ps。 {c<cSrfI
8LY^>.
ps.getItems()得到已分页好的结果集 y3P4]sq
ps.getIndexes()得到分页索引的数组 /
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ps.getTotalCount()得到总结果数 yEkwdx5!(
ps.getStartIndex()当前分页索引 \J-D@b;
ps.getNextIndex()下一页索引 fd&>p
ps.getPreviousIndex()上一页索引 F U)=+m
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 Sh:_YD^(
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,尤其是上面的示例代码,让我着实觉得该对我原来的分页查询做 >^ E*7Bfp
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一下代码重构了。 Qn;,OBk
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我把原本我的做法也提供出来供大家讨论吧: O]oH}#5b
N]F}Z#h
首先,为了实现分页查询,我封装了一个Page类: ku#WQL
java代码: +.-mqtM
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/*Created on 2005-4-14*/ h"f_T
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package org.flyware.util.page; ,hp8b$
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/** c/l^;6O/!\
* @author Joa \4O_@d`A
* C>QWV[F
*/ Tz&h[+ 6`
publicclass Page { v]}\Ns/
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/** imply if the page has previous page */ _
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privateboolean hasPrePage; &7r a
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/** imply if the page has next page */ StiWa<"c
privateboolean hasNextPage; x
}]"jj2x
D J7U6{KLq
/** the number of every page */ hV
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privateint everyPage; 3`Xzp
jVqpokWH
/** the total page number */ COHook(:
privateint totalPage; wEQZ9?\
msQ?V&+<
/** the number of current page */ LG??Q+`l
privateint currentPage; 1jpft3*x
RNt9Qdr4y
/** the begin index of the records by the current '($$-P\/
*JZlG%z
query */ vx}BTH
privateint beginIndex; 8d&%H,
}hcY5E-n
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/** The default constructor */ `A-
public Page(){ vhDtjf/*
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} MSB/O.
p =-~qBw
/** construct the page by everyPage (k_9<Yb3
* @param everyPage kM(m$Oo.
* */ )4>7X)j>
public Page(int everyPage){ ARG8\qU
this.everyPage = everyPage; S 8)!70
} P(a}OlG
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/** The whole constructor */ R\]C;@J<
public Page(boolean hasPrePage, boolean hasNextPage, \9`.jB~<
*Rxn3tR7
Rr}m(e=
int everyPage, int totalPage, \u;`Lf
int currentPage, int beginIndex){ 3rR1/\
this.hasPrePage = hasPrePage; ` $q0fTz
this.hasNextPage = hasNextPage; qqys`.
this.everyPage = everyPage; 7y_<BCx
h
this.totalPage = totalPage; \ _?d?:#RD
this.currentPage = currentPage; T1'\!6_5
this.beginIndex = beginIndex; ncTMcu
} Y~?Z'uR
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/** *]nk{jo2
* @return `>OKV;~{z
* Returns the beginIndex. 6Cfsh<]b
*/ <j3|Mh_(I
publicint getBeginIndex(){ eHR]qy 0_X
return beginIndex; A4rkwM
} u'T-}95 V
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/** ?Cx=!k.
* @param beginIndex M+b?qw
* The beginIndex to set. 7
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*/ B:Awy/XMi
publicvoid setBeginIndex(int beginIndex){ +O.qYX
this.beginIndex = beginIndex; S)/548=`
} jmcys
_N3
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/** (H\ `/%Bp
* @return nzbAQ3v
* Returns the currentPage. $VhY"<
*/ &9"Y:),
publicint getCurrentPage(){ }6=?
zs}
return currentPage; _ {6l}
} LF#[$
so{i
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/** 1g j GaC
* @param currentPage %F^,6y
* The currentPage to set. +cKOIMu9
*/ #on ,;QN
publicvoid setCurrentPage(int currentPage){ kt=&mq/B
this.currentPage = currentPage; ^aQ&.q
} &I%E8E
}D.\2x(J
/** X5)(,036
* @return Kr;=4xg=
* Returns the everyPage. G*jq5_6
*/ N;k )>
publicint getEveryPage(){ <lLJf8OK
return everyPage; M?GkHJ %!
} ia3!&rZ
rm-;Z<
/** USS%T<Vk
* @param everyPage X*:,|
* The everyPage to set. E0yx
@Vx
*/ [rL 8L6,!
publicvoid setEveryPage(int everyPage){ %wI)uJ2
this.everyPage = everyPage; ;8^(Z
} u?H.Z
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/**
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* @return 1
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* Returns the hasNextPage. Ob}XeN(L3
*/ Rjv;[
publicboolean getHasNextPage(){ 4O/IT1+A
return hasNextPage; oZ ^,*
} ect$g#
@|bJMi
/** mx
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* @param hasNextPage s`0IyQXVU
* The hasNextPage to set. W/}_ y8q
*/ HFlExau
publicvoid setHasNextPage(boolean hasNextPage){
sFnR;
this.hasNextPage = hasNextPage; #9F>21UU
} E31YkD.A
V!>j:"
/** 9v?@2sOoE
* @return !2^~ar{2
* Returns the hasPrePage. WuFBt=%
*/ TdT`Vf
publicboolean getHasPrePage(){ 5 jUy[w @
return hasPrePage; D$*o}*mb
} Yl:[b{Py
WglpWp)
/** &%;n9K
* @param hasPrePage o*ucw3s>
* The hasPrePage to set. 4nQ5zwiV
*/ e9tb]sAG
publicvoid setHasPrePage(boolean hasPrePage){ 1ltW9^cF}
this.hasPrePage = hasPrePage; p>#q* eU5
} DEt!/a{X
z[myf]@
/** %5DM ew
* @return Returns the totalPage. d3S Me
* .\&k]}0qA?
*/ 3HW&\:q5'M
publicint getTotalPage(){ {?2|rv)
return totalPage; 'W>y v
} <RZqs
#f HnM+
/**
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* @param totalPage ^SKHYo`,,N
* The totalPage to set. )rt%.`
*/ SMJRoK3
publicvoid setTotalPage(int totalPage){ Jj5VBI!Ok
this.totalPage = totalPage;
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} {
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Cb`, N
} s{8=Q0^
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BV
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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 RqP_^tB
RyG6_G}
个PageUtil,负责对Page对象进行构造: B]:|;d
java代码: BzkfB:wr
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DV[FZ
/*Created on 2005-4-14*/ `9+R]C]z8
package org.flyware.util.page; u@`a~
G%;>_E
import org.apache.commons.logging.Log; 6H5o/)Q~
import org.apache.commons.logging.LogFactory; pe2:~}WB
w6)Q5H53)
/** f 1+
* @author Joa {"%a-*@%
* kh:_,g
*/ Lo#G. s|
publicclass PageUtil { x[Hx.G}5+
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privatestaticfinal Log logger = LogFactory.getLog _ DT,iF*6
dJ Q K|/
(PageUtil.class); JbS[(+o
O9/)_:Wdh
/** .{*l,
* Use the origin page to create a new page M\
* @param page *hJWuMfY,
* @param totalRecords #ojuSS3
* @return ,aGIq. *v
*/ *78c2`)[
publicstatic Page createPage(Page page, int l>`66~+s,`
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totalRecords){ Ry"4v_e9
return createPage(page.getEveryPage(), #+V4<o
a:`<=^:4,
page.getCurrentPage(), totalRecords); a$Y{ut0t(
} T*PEUq
dcD#!v\0
/** kWVk^,
* the basic page utils not including exception iLNUydiS
[ }Tb2|
handler r@qLG"[\c
* @param everyPage k ,+,,W
* @param currentPage PnInsf%;
* @param totalRecords Z"_8l3
* @return page 2[uFAgf@
*/ 1'Q6l
publicstatic Page createPage(int everyPage, int Rvx7}ZL!
1iLo$
currentPage, int totalRecords){ 2,`X@N`\
everyPage = getEveryPage(everyPage); $fT5Vc]B4
currentPage = getCurrentPage(currentPage); f\_PNZCc
int beginIndex = getBeginIndex(everyPage, qlYi:uygY
O6)Po
currentPage); .ml\z5
int totalPage = getTotalPage(everyPage, K sE$^`
oe2*$\?.
totalRecords); u_
l?d
boolean hasNextPage = hasNextPage(currentPage, gh\u@#$8
,=4,eCS
totalPage); Z|Rc54Ct
boolean hasPrePage = hasPrePage(currentPage); @KU;'th
;CF:cH*
returnnew Page(hasPrePage, hasNextPage, *pSnEWwE
everyPage, totalPage, g3&nxZ
currentPage, @48!e-W
+$nNYD
beginIndex); uax0%~O\
} ncOgSj7e
zPqJeYK
privatestaticint getEveryPage(int everyPage){ M9BEG6E9
return everyPage == 0 ? 10 : everyPage; 2w8cJadT'p
} w43b=7
4:NMZ `~
privatestaticint getCurrentPage(int currentPage){ ^Cp2#d*
return currentPage == 0 ? 1 : currentPage; N\B&|;-V
} Xb>SA|6[|
H1B%}G*Ir-
privatestaticint getBeginIndex(int everyPage, int fuv{2[NV
d;0]xG?%=
currentPage){ {}ADsh@7d'
return(currentPage - 1) * everyPage; WQ[nK5#
} '@hUmrl
=FV(m
S
privatestaticint getTotalPage(int everyPage, int tlUh8os
7<MEM NYX
totalRecords){ d94k
int totalPage = 0; Kc2y
gDLS)4^w
if(totalRecords % everyPage == 0) EJTM
>Rpor
totalPage = totalRecords / everyPage; nb=mY&q}~
else 4c 8{AZ
totalPage = totalRecords / everyPage + 1 ; l1'v`!
k)*apc\W
return totalPage; M.}J SDt
} kBcTXl
]bh%pn
privatestaticboolean hasPrePage(int currentPage){ JG'%HJ"D
return currentPage == 1 ? false : true; i]?
Eq?k
} 5;" $X 1{
v+ in:\Dv
privatestaticboolean hasNextPage(int currentPage, WA43}CyAe
TmLCmy!
int totalPage){ sBa:|(Y.
return currentPage == totalPage || totalPage == d wG!]j>:_
ud5}jyJ
0 ? false : true; 3lZl
} vVvF e~y]
5G\OINxy
gFHBIN;u
} ='b)6R
S%}G 8Ty
v"ORn5
T5zS3O
K=JDl-#!
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。 Q;y5E`G
.-M5.1mo\(
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 xcWR#z{z
lqmQQ*Z
做法如下: e(
@</W
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 >\<eR]12
Y`]P&y
的信息,和一个结果集List: s)]T"87H'_
java代码: ZJZSt% r
x
cAs}y}
`b8nz 7
/*Created on 2005-6-13*/ W g7
eY'FE
package com.adt.bo; &(Fm@ksh\
=O0A(ca"g
import java.util.List; Vlz\n
Lg!E
import org.flyware.util.page.Page; K=0xR*ll5
4Xa]yA =
/** :FS5BT$=
* @author Joa
b7\> =
*/ 57{T
p:|
publicclass Result { 8b]4uI<
=-:%~ng
private Page page; u3O@ccJ;
mih}?oi
private List content; ,:L^vG@*
v5a\}S<(
/** Ly8=SIZ
* The default constructor z/4<x?}+hE
*/ Uvm.|p_V
public Result(){ I@Hx
LEGj
super(); iu8Q &Us0P
} 96~y\X@x
lPxhqF5pP
/** T})q/oUqK
* The constructor using fields J~WT;s
* +%\Ci!%b
* @param page %?].(
Lc
* @param content L%Zr3Ct
*/ K)>F03=uE
public Result(Page page, List content){ (["kbPma
this.page = page; pu/5#[MC)^
this.content = content; ;.sYE/ZVi
} ^_@[1'^
'a+^= c
/** {Dl@/fz
* @return Returns the content. z;oia!9z
*/ TxF^zx\
publicList getContent(){ "i#g [x
return content; 4y3c=L
No
} ed',\+.uB
PZqp;!:xz
/** hO$Gx*e$
* @return Returns the page. zCo$YP#5_
*/ bLG7{qp
public Page getPage(){ _h^.`Tz,
return page; /+%aSPQ
} $}tF66d
kEC^_sO"
/** "*<vE7
* @param content Lw[=pe0e
* The content to set. 5\h 6"/6Df
*/ lBFKfLp&
public void setContent(List content){ q>BJ:_I
i
this.content = content; #2U# h-vI
} E~WbV+,3
]j:k!=Ss?
/** *Oy*
\cX2[
* @param page 0;><@{'
* The page to set. Za!KM
*/ `mteU"{bx
publicvoid setPage(Page page){ 3>7{Q_5
this.page = page; auAz>6L
} k;cX,*DIn
} hu0z
36
_J,rql@nG<
.qohHJ&
na
$MR3@e
cS YCMQ1ro
2. 编写业务逻辑接口,并实现它(UserManager, 2_ u+&7
QAxy?m,'
UserManagerImpl) %XukiA+
java代码: }(u:K}8
KPz0;2}
BZ.l[LMp
/*Created on 2005-7-15*/ e.MyJ:eL
package com.adt.service; eC<RM Q4
sjLMM_'
import net.sf.hibernate.HibernateException; [6RODp3')
Rl cL(HM
import org.flyware.util.page.Page; +%9Re5R
ui)mYR[8X
import com.adt.bo.Result; Ix_w.f=8
k%~;mu"4}
/** jSvq1$U
* @author Joa f:\)!
&W
*/ $*X?]?
publicinterface UserManager { DjK7_'7(L
:l]qTCmY
public Result listUser(Page page)throws &1T)'Bn
3xz~##
HibernateException; W"@'}y
RYvcuA)
} %,vq@..^
YC6guy>
T;B FO5G@
L bJf5xdi
y lczM^@
java代码: +$L}B-F
D~"a"
Dom]w.W5
/*Created on 2005-7-15*/ S+.>{0!S"
package com.adt.service.impl; hfIP
N}nE9z5
import java.util.List; y7h^_D+Ce
>ryA:TO{
import net.sf.hibernate.HibernateException; "#pxZ
B=
|$IL:W6
import org.flyware.util.page.Page; f@!9~s
import org.flyware.util.page.PageUtil; o9|
OL
|(W04Wp"@
import com.adt.bo.Result; egA*x*8
import com.adt.dao.UserDAO; l*hWws[
import com.adt.exception.ObjectNotFoundException; -!7Z
import com.adt.service.UserManager; HTiLA%%6
{9 |*au(K
/** -`Z!p
* @author Joa ML|?H1m>
*/ AEj%8jh
publicclass UserManagerImpl implements UserManager { nl(GoX$vRQ
TtrO _D
private UserDAO userDAO; g?xXX
/Qe
I:DAn!N-A*
/** FsOJmWZ
* @param userDAO The userDAO to set. w3
vZ}1|
*/ 1l)j(,Zd*
publicvoid setUserDAO(UserDAO userDAO){ 7&P70DO
this.userDAO = userDAO; yy/'B:g
} Jjj;v2uSK
Ppl :_Of
/* (non-Javadoc) Z>R@
* @see com.adt.service.UserManager#listUser a.UYBRP/l
Pm^FSw"
(org.flyware.util.page.Page) 9 9:.j=
*/ <<cezSm
public Result listUser(Page page)throws `Mg3P_}=
l v:GiA"X
HibernateException, ObjectNotFoundException { 0@{bpc rc
int totalRecords = userDAO.getUserCount(); k1g-%DB
if(totalRecords == 0) l%Ke>9C
throw new ObjectNotFoundException X4\T=Q?uLx
E83$(6z
("userNotExist"); g*FHZM*N9
page = PageUtil.createPage(page, totalRecords); E|-5=!]fX
List users = userDAO.getUserByPage(page); nnBS;5
returnnew Result(page, users); dEMv9"`*!
} `x?_yogPM
$D65&R
} ,ko#z}Z4r,
JDa_;bqL
POl-S<QV
E[ -yfP~[
t5b cQ@Y
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 ZR=i*y
@mu{*. &
询,接下来编写UserDAO的代码: %/\sn<6C}
3. UserDAO 和 UserDAOImpl: G2n.NW#d4
java代码: 5FB3w48
yMkR)HY
\>"Zn7
/*Created on 2005-7-15*/ X xwcvE
package com.adt.dao; c CZ$TH
#sF#<nHZ
import java.util.List; hEo$Jz`
]==7P;_-
import org.flyware.util.page.Page; p; , V
)AieO-4*
import net.sf.hibernate.HibernateException; $aT '~|?
&
\5Ur^t
/** u&={hJ&7
* @author Joa
>_]Ov:5
*/ # ^,8JRA
publicinterface UserDAO extends BaseDAO { 1xkk5\3]
9+ve0P7$
publicList getUserByName(String name)throws \cX9!lHl
B/Q>i'e
HibernateException; Y/m-EL
)iIsnM
publicint getUserCount()throws HibernateException; +DefV,Ny
$u,A/7\s
publicList getUserByPage(Page page)throws cRag0.[
TL"+Iv2]/$
HibernateException; d8
v9[4
2XUIC^<@s
} aRn""3[
9.~_swkv
~k@{b&
GM^H
)8U
j)Q}5M
java代码: !p36OEx
^^uY)AL
$mq+/|bn
/*Created on 2005-7-15*/ X?r$o>db
package com.adt.dao.impl; F2(^OFh
GX.a!XQ@!
import java.util.List; n
sN n>{
h{~GzrL*
import org.flyware.util.page.Page; vgNrHq&2q
z+0#H39 &
import net.sf.hibernate.HibernateException; j:48l[;ed
import net.sf.hibernate.Query; X`E}2|q'
:$X dR:f}}
import com.adt.dao.UserDAO; X,8Zn06M
RWDPsZC
/** >)>~S_u
* @author Joa vON7~KA
*/ $b_~
public class UserDAOImpl extends BaseDAOHibernateImpl )iPU
5Tidb$L;Du
implements UserDAO { L&5zr_
h,fahbH-
/* (non-Javadoc) ?WS.RB e2
* @see com.adt.dao.UserDAO#getUserByName p[!9 objU
S!R(ae^}
(java.lang.String) 6l"4F6
*/ #aP;a-Q|k
publicList getUserByName(String name)throws !.q#X^@>L
ZM=eiJZ
HibernateException { $iH
String querySentence = "FROM user in class PIsXX#`7;
[H`5mY@
com.adt.po.User WHERE user.name=:name"; 0V2~
Query query = getSession().createQuery p+2%LYR u
z`dnS]q9
(querySentence); :`@W`V?6-
query.setParameter("name", name); W3MH8z
return query.list(); V<n#%!M5gV
} tKi^0vE8
<V8=*n"mR
/* (non-Javadoc) qV$0 ";d
* @see com.adt.dao.UserDAO#getUserCount() %we! J%'Y]
*/ s"wz !{G4
publicint getUserCount()throws HibernateException { =NRiro
int count = 0; Tkh?F5l
String querySentence = "SELECT count(*) FROM dTU`@!f
bh5C
user in class com.adt.po.User"; y<yU5
Query query = getSession().createQuery w- wJhc|
@]],H0
(querySentence); M!PK3
count = ((Integer)query.iterate().next t |:XSJ9
Fow{-cs_p
()).intValue(); o|VM{5
return count; 1!ijRr
} A1jA$
d\ Xijy
/* (non-Javadoc) O;#0Yg
* @see com.adt.dao.UserDAO#getUserByPage "[ >ql1t{b
Op iVQr:
(org.flyware.util.page.Page) lYrW"(2
*/ <+`}:
A
publicList getUserByPage(Page page)throws |e&hm
~R1
6"bdbV=t
HibernateException { Hg[AulNna
String querySentence = "FROM user in class ~</H>Jd
<QK2Wc_}-"
com.adt.po.User"; oJ0
#U
Query query = getSession().createQuery w 1O)
yjChnp
Cc
(querySentence); zhACNz4tJ
query.setFirstResult(page.getBeginIndex()) m8v=pab e
.setMaxResults(page.getEveryPage()); :\#/T,K"
return query.list(); ]=5D98B
} ~uO9>(?D
m\|ie8
} kQtnT7
I9jzR~T
$K~ t'wr
/}-LaiS
&?SU3@3|
至此,一个完整的分页程序完成。前台的只需要调用 &PEw8: TX
Ni61o?]Nj
userManager.listUser(page)即可得到一个Page对象和结果集对象 `S/;S<';
sHMZ'9b
的综合体,而传入的参数page对象则可以由前台传入,如果用 OQsF$%*
=q*j". <
webwork,甚至可以直接在配置文件中指定。 4p/d>DTiM
4ko(bW#jL
下面给出一个webwork调用示例: nx`I9j\
java代码: -(![xZ1{K
kM @heFJb.
2NqO,B|R
/*Created on 2005-6-17*/ pGSS
package com.adt.action.user; iED
gcg7
gA DF
import java.util.List; }tH6E
GMoE,L
import org.apache.commons.logging.Log; Nc[u?-
import org.apache.commons.logging.LogFactory; :+}Eo9
import org.flyware.util.page.Page; Jg%jmI;Y
kT4Tb%7KM
import com.adt.bo.Result; ;PX>] r5U0
import com.adt.service.UserService; Q2!vO4!<N
import com.opensymphony.xwork.Action; >[gNQJ6
gLPgh%B4
/** s4{ >7`N2
* @author Joa Ba]^0Y
u
*/ [5Pin>]z
publicclass ListUser implementsAction{ 2t"&>1
Z\*jt B:
privatestaticfinal Log logger = LogFactory.getLog co%-d
6"Rw&3D?
(ListUser.class); +d,Z_ 6F
si3@R?WR6*
private UserService userService; =G%L:m*
XVkCYh4,
private Page page; Q"sszz
4BAG GD2
privateList users; RL3G7 ;X
la[>C:8IG
/* A"~4|`W
* (non-Javadoc) {Zy)p%j8
* IH~[/qNk
* @see com.opensymphony.xwork.Action#execute() <ULydBom
*/ 'z3I*[!
publicString execute()throwsException{ ^N:bT;;$nZ
Result result = userService.listUser(page); Q !G^CG
page = result.getPage(); E >lW'
users = result.getContent(); d;O4)8>
return SUCCESS; O;?Nz:/q
} uu+)r
%.VFj7J
/** T:(c/>
* @return Returns the page. 'Q F@@ 48
*/ I9;,qd%<T
public Page getPage(){ `E2HQA@
return page; Z`Sbq{Kx
} L4-v'Z;
2io~pk>
/** 1A.e cv'
* @return Returns the users. V+&C_PyC
*/ ~V6wcXd
publicList getUsers(){ |QB[f*y5
return users; !U8n=A#,-
} >crFIkOJ
_/`H<@B_U
/** q,v)X
* @param page 9S]]KEGn4
* The page to set. ==)q{e5
*/ Yb;$z'
publicvoid setPage(Page page){ XdxSi"+
this.page = page; >qC,IQ'
} r`GA5}M
Th>ff)~e
/** G"|`&r@
* @param users %$CV?K$C
* The users to set. K)[DA*W
*/ %{HeXe
publicvoid setUsers(List users){ DA wUG
this.users = users; $Cx ?%X^b
} |g,99YIv>
Js}1_K
/** ni`uO<\U
* @param userService {ZIEIXWb2
* The userService to set. R7ze~[oF
*/ J_rb3
publicvoid setUserService(UserService userService){ I$HO[Z!
this.userService = userService; g?i0WS
} @K=C`N_22
} GZWU=TC2{2
GW;O35
m
#4BwYj(Sl
GLtd6; V
"1HKD
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, qe<aJn
^M6R l0
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 I )wc&>Lc
@Tz}y"VG
么只需要: x,: DL)$1
java代码: $~5ax8u&!#
Dlqvz|X/
"cD MFu
<?xml version="1.0"?> 5e}adHjM
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork V18A|]k
^LAnR>mz^r
1.0//EN" "http://www.opensymphony.com/xwork/xwork- &Xh_`*]ox
;nbV-<e
1.0.dtd">
5VZZk%oy
B3g#)
<xwork> <e'/z3TbRW
L-eO_tTh0
<package name="user" extends="webwork- <@H`5[R
_2
oZhJ
interceptors"> s&7TARd
Ci(c`1av
<!-- The default interceptor stack name ( we)0AxF'
;fe~PPT
--> 0"J0JcFX
<default-interceptor-ref t5RV-$
=M`Xu#eRk
name="myDefaultWebStack"/> qN\?cW'
tg6iHFa
<action name="listUser" /l>!7
9oQ$w?=#$
class="com.adt.action.user.ListUser"> PT39VI
=
<param )0?u_Z]w9
>0E3Em<(}l
name="page.everyPage">10</param> _|VF^\i
<result s
a{x.2/o}
<N{Y*,^z
name="success">/user/user_list.jsp</result> }?^]-`b
</action> d}Xb8SaE%c
lsA?|4`mn
</package> -BcnJK0
{R8)DK
</xwork> sZPyEIXie
9%Qlg4~<s
*BHp?cn;F2
~yiw{:\
weC.kx
{5Sy=Y
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 2@,rIve
)~-r&Q5d
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。 8_/,`}9
@Nn'G{8OG
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 %>-?oor
=z zmz7op
`Z^\<{z
[JYy
P&IS$FC.\
我写的一个用于分页的类,用了泛型了,hoho :!yPR
~s*kuj'%+
java代码: &}r-C97
S S fNI>
d<RJH
package com.intokr.util; w@WPp0mny
K_F"j!0
import java.util.List; GIhX2EvAS
5Nl?Km~
/** q.VZ P
* 用于分页的类<br> gH
yJ~
* 可以用于传递查询的结果也可以用于传送查询的参数<br> <:4b4Nl
* SZvp%hS0
* @version 0.01 ipyc(u6Z5
* @author cheng CsEU:v
*/ A|YiSwyy
public class Paginator<E> { _*ar\A`
privateint count = 0; // 总记录数 I]a [Ngj
privateint p = 1; // 页编号 f7/M _sx
privateint num = 20; // 每页的记录数 OlP1Zd/l
privateList<E> results = null; // 结果 q$PO.#
-"rANP-UI
/** ^hcK&
* 结果总数 '^`iF,rg
*/ wZVLpF+7
publicint getCount(){ XT?wCb41R
return count; Ca-.&$f
} 7(d#zu6n
*dN_=32u
publicvoid setCount(int count){ KM?w{ ~9
this.count = count; :7~DiH:Q
} mVEIHzk2b
kD(#LM<9s
/** \k{d'R#~(
* 本结果所在的页码,从1开始 Mm;[f'{M)
* $18?Q+?3
* @return Returns the pageNo. \5}*;O@
*/ _2hZGC%&E
publicint getP(){ @z^7*#vQv
return p; U/-k'6=M
} "RTv[n!
.F N
6/N\
/** W ",yq|
* if(p<=0) p=1 b=5ZfhIg[
* N:;z~`
* @param p .03Rp5+v
*/ tUt_Q;%yC
publicvoid setP(int p){ p3>Md?e
if(p <= 0) D#A6s32a
p = 1; TKQ^D
this.p = p; J9MAnYd)i
} (3~^zwA
ICiGZ'k
/** gJ~CD1`O
* 每页记录数量 aW}d=y[
*/ @_wJN Qo`
publicint getNum(){ s
bd$.6
|&
return num; djqw5kO:R
} [^W
+^3V
G[6i\Et
/** 7Ck3L6J#
* if(num<1) num=1 ZQ>Q=eCs 1
*/ X]o"4#CQIX
publicvoid setNum(int num){ a?xZsR
if(num < 1) P EMBh?)g
num = 1; dL_9/f4
this.num = num; M2\c0^R
} I E{:{b\
\}~71y}
/** 34Cnbtq^
* 获得总页数 |AT`(71
*/ ;/t~MH
publicint getPageNum(){ %w?C)$Kn\
return(count - 1) / num + 1; WZTAXOw
} =sAU5Ag68
Z*ag{N
/** r`\@Fv,
* 获得本页的开始编号,为 (p-1)*num+1 T$<yl#FY
*/ t fD7!N{
publicint getStart(){ yZN~A:
return(p - 1) * num + 1; e)N<r
} 4j8$&~/
~FQHT?DAo
/** 0b['{{X(
* @return Returns the results. %~} ,N
*/ 3 qJ00A
publicList<E> getResults(){ xkU8(=
return results; u:Ye`]~o
} m'N8[ o|h
9aNOfs8(
public void setResults(List<E> results){ (#Xs\IEV F
this.results = results; =z]rZSq*o
} &H
P g>
|sY
public String toString(){ )0DgFA6k_
StringBuilder buff = new StringBuilder q#SEtyJL
T
"hjL
(); wph8ln"C-
buff.append("{"); ;mRZ_^V;
buff.append("count:").append(count); oe|8
buff.append(",p:").append(p); b(CO7/e>
buff.append(",nump:").append(num); xcn~KF8
buff.append(",results:").append >rJ**y
cGR) $:
(results); #C~ </R%
buff.append("}"); c*]f#yr?
return buff.toString(); g cB
hEw
} ^b|I^TN0
h"/'H)G7_&
}
2W`WOBz
Xs# _AX
JWYe~