Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 ;'HF'Z
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 Z>2]Xx%
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据这一功能,我设计了通用的抽象Bean基类和分页类支持,代码来 O R
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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 s<&[\U
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分页支持类: <'&F;5F3V
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java代码: 0pN{y}x,
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package com.javaeye.common.util; iF9_b
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import java.util.List; f^9&WT
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publicclass PaginationSupport { DMZ`Sx
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publicfinalstaticint PAGESIZE = 30; >]&X ^V%Q#
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privateint pageSize = PAGESIZE; l67KJ
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privateList items; Sj-[%D*
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privateint totalCount; |!LnAh
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privateint[] indexes = newint[0]; Z]vL%Gg*!
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privateint startIndex = 0; % fhNxR
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public PaginationSupport(List items, int mhzYz;}
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totalCount){ |LmSWy*7
setPageSize(PAGESIZE); $}tjS3klr
setTotalCount(totalCount); "C74
setItems(items); s@!$='|
setStartIndex(0); R1%y]]*-P
} `ZGcgO<c\
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public PaginationSupport(List items, int u^4h&fL
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totalCount, int startIndex){ SUE
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setPageSize(PAGESIZE); p2d\ZgWD=)
setTotalCount(totalCount); 9DE)S)e8
setItems(items); YBjdp=als
setStartIndex(startIndex); >n$!<
} 3M<!?%v\A
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public PaginationSupport(List items, int {p/YCch,
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totalCount, int pageSize, int startIndex){ {THqz$KN
setPageSize(pageSize); NP_?f%(
setTotalCount(totalCount); &;>4N"]
setItems(items); :6Pad
setStartIndex(startIndex); 4JO@BV >t
} BHr|.9g]%%
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publicList getItems(){ (3%t+aqq
return items;
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} ]P1YHw9
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publicvoid setItems(List items){ `s/?b|,
this.items = items; ~F[L4y!sL
} L
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publicint getPageSize(){ O@&+} D>
return pageSize; REA;x-u*
} ! OE*z $\
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publicvoid setPageSize(int pageSize){ /A07s[L
this.pageSize = pageSize; 5*G%IR@@LK
} ;j'Daupt;=
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publicint getTotalCount(){ I}.i@d'O
return totalCount; ZGz|m0b (
} YfDWM7x7,
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publicvoid setTotalCount(int totalCount){ yrr)
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if(totalCount > 0){ >^SEWZ_[
this.totalCount = totalCount; ^T079=$5
int count = totalCount / .C!vr@@]
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pageSize; <kc#thL
if(totalCount % pageSize > 0) 4Z5#F]OA7
count++; Yl({)qK{
indexes = newint[count]; S# we3
for(int i = 0; i < count; i++){ p2 ! FcFi
indexes = pageSize * {IM! Wb
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i; 1FERmf? ?d
} P:{<*`q
}else{ 2 y8~#*O
this.totalCount = 0; qVgd(?hJ#
} 2qU&l|>
} &M[f&_"8Q
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publicint[] getIndexes(){ 4s.]M>Yb
return indexes; SF<Vds}A2
} 7$uJ7`e
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publicvoid setIndexes(int[] indexes){ Sc$UZ/qPT
this.indexes = indexes; ]z ==
} p]&j;H.
}nrXxfu
publicint getStartIndex(){ ^DAu5 |--R
return startIndex; |m*.LTO
} a.%LHb
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publicvoid setStartIndex(int startIndex){ k*Nr!Z!}
if(totalCount <= 0) >fs2kha
this.startIndex = 0; oy\B;aAK
elseif(startIndex >= totalCount) SNY (*
this.startIndex = indexes IOl+t,0x&
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[indexes.length - 1]; :#{Xuy:
elseif(startIndex < 0) {6,|IGAq
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this.startIndex = 0; +l0g`:
else{ {^ec(EsO#
this.startIndex = indexes {})$
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[startIndex / pageSize]; ff2d@P,!
} 0!GAk
} [~mGsXV
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publicint getNextIndex(){ c_kxjzA#
int nextIndex = getStartIndex() + mucY+k1>g
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pageSize; ' f}^/`J
if(nextIndex >= totalCount) %[B &JhT
return getStartIndex(); l9qq;hhGP,
else 4T Gg`$e;
return nextIndex; bO9F rEz5
} pE^L Qi
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publicint getPreviousIndex(){ {1#5\t>9yD
int previousIndex = getStartIndex() - #Ru+|KL
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pageSize; 2a (w7/W:
if(previousIndex < 0) {SqY77
return0; rQ30)5^V|
else $O%lYQY]
return previousIndex; 1[} =,uaM
} q.K >v'
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} u17Da9@;
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抽象业务类 NV36Q^Am[
java代码: yE{l
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/** h'MX{Wm.
* Created on 2005-7-12 qAivsYN*
*/ `vL R;D
package com.javaeye.common.business; $Z.c9rY1
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import java.io.Serializable; ` *$^rQS
import java.util.List; wW6?.}2zU
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import org.hibernate.Criteria; h&h]z[r R
import org.hibernate.HibernateException; MCz+l0
import org.hibernate.Session; |pq z(j7
import org.hibernate.criterion.DetachedCriteria; nFw&vR/q
import org.hibernate.criterion.Projections; @#*B|lHE
import 4w2V["?X1
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org.springframework.orm.hibernate3.HibernateCallback; '9$xOrv
import &XrF#s
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org.springframework.orm.hibernate3.support.HibernateDaoS je_77G(F
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upport; B 8C3LP}?
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import com.javaeye.common.util.PaginationSupport; XfViLBY(
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public abstract class AbstractManager extends ]2h~Db=
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HibernateDaoSupport { ^R>&^"oI
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privateboolean cacheQueries = false; P1T LH2)
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privateString queryCacheRegion; "W\
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publicvoid setCacheQueries(boolean Bi?.G7>
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cacheQueries){ @@SG0YxZ
this.cacheQueries = cacheQueries; FIC
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} dgX 0\lKpf
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publicvoid setQueryCacheRegion(String TQID-I
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queryCacheRegion){ lYQcQ*-
this.queryCacheRegion = z Lf^O%zN
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queryCacheRegion; R%7k<1d'`
} CIO&VK
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publicvoid save(finalObject entity){ CFRo>G
getHibernateTemplate().save(entity); ~l{CUQU
} MttVgNV
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publicvoid persist(finalObject entity){ :rk]o*
getHibernateTemplate().save(entity); 7v%~^l7:x
} t?YGGu^
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publicvoid update(finalObject entity){ cJi5\<b
getHibernateTemplate().update(entity); '=%vf
} TyGXDU
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publicvoid delete(finalObject entity){ XXxX;xz$
getHibernateTemplate().delete(entity); oBAD4qK
} (Ozb +W?
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publicObject load(finalClass entity, #_|b;cf
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finalSerializable id){ h'IBVI!P
return getHibernateTemplate().load . +.Y`0
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(entity, id); mP3:Fc_G
} b$.N8W%
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publicObject get(finalClass entity, Z1^S;#v
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finalSerializable id){ Ww)qBsi8
return getHibernateTemplate().get $m~&| s
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(entity, id); {chZ&8)f
} Y>/_A%vQU
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publicList findAll(finalClass entity){ ja~Dp5
return getHibernateTemplate().find("from G u_\ySV/y
/*>}y$
" + entity.getName()); %7 yQ0'P
} 4h_YVG]ur
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publicList findByNamedQuery(finalString uF|_6~g
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namedQuery){ IDJ2epW*;
return getHibernateTemplate _aOs8#(X
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().findByNamedQuery(namedQuery); 3u[8;1}7Q
} {]8|\CcY?
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publicList findByNamedQuery(finalString query, uq-`1m}
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finalObject parameter){ I}o}
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return getHibernateTemplate {DKZ~
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().findByNamedQuery(query, parameter); VpYD/Oj4;
} zSD_t
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publicList findByNamedQuery(finalString query, T30fp
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finalObject[] parameters){ 0wNlt#G;{
return getHibernateTemplate w0Nm.=I-
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().findByNamedQuery(query, parameters); $\vNSTE
} Ns1n|^9
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publicList find(finalString query){ #k)z5vZ$h
return getHibernateTemplate().find T:'JA
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(query); <'$>&^!^
} \ +sa[jK
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publicList find(finalString query, finalObject GVlT+Rs7
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parameter){ 6@/k|t>OT
return getHibernateTemplate().find "&f|<g5
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(query, parameter); ]o"E4Vht
} `5h^!="
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public PaginationSupport findPageByCriteria BI-'&kPk
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(final DetachedCriteria detachedCriteria){ 5vR])T/S0
return findPageByCriteria 'v0rnIsI?
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); Zqe$S
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} D=3Z] 'A
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public PaginationSupport findPageByCriteria PPySOkmS3
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(final DetachedCriteria detachedCriteria, finalint 6Sn&;ap
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startIndex){ "\}h
return findPageByCriteria 9Xa.%vw>
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(detachedCriteria, PaginationSupport.PAGESIZE, x`C"Z7t
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startIndex); `@1e{?$
} o^(I+ <el
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public PaginationSupport findPageByCriteria p9 ,[kb
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(final DetachedCriteria detachedCriteria, finalint PIo@B|W-SX
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pageSize, {j`8XWLZZN
finalint startIndex){ +L'Cbv= "
return(PaginationSupport) &{<hY|%
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getHibernateTemplate().execute(new HibernateCallback(){ L?|}!
publicObject doInHibernate _U4@W+lhX_
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(Session session)throws HibernateException { #*y.C[^5{
Criteria criteria = -u"|{5? '
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detachedCriteria.getExecutableCriteria(session); ZD|F"v.
int totalCount = 3`{
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((Integer) criteria.setProjection(Projections.rowCount C<T6l'S{?
pnp8`\cIH
()).uniqueResult()).intValue(); J[Mj8ee#
criteria.setProjection 9a]o?>`E
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(null); Rsq EAdZw[
List items = u$5.GmKm
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criteria.setFirstResult(startIndex).setMaxResults '4#NVXVQm
?Q"<AL>Z
(pageSize).list(); "m6G;cv
PaginationSupport ps = \zk>cQ
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new PaginationSupport(items, totalCount, pageSize, ?,v&
o>*
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startIndex); @@\px66
return ps; nr&|
} ;3& wO~lW
}, true); PcZ<JJ16F$
} ^:ny
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public List findAllByCriteria(final E'mT%@MOM
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DetachedCriteria detachedCriteria){ 9mXmghoCO
return(List) getHibernateTemplate 8tjWVo
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().execute(new HibernateCallback(){ `.pd %\
publicObject doInHibernate Z<AZO ^
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(Session session)throws HibernateException { 6?.S-.Mr
Criteria criteria = />:$"+gKo
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detachedCriteria.getExecutableCriteria(session); jg%mWiKwK7
return criteria.list(); Df2$2VU
} :iE`=( o
}, true); wK fq'W{
} sD?Ynpt
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public int getCountByCriteria(final 9)=bBQyr:
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DetachedCriteria detachedCriteria){ ';.y`{/
Integer count = (Integer) !~7lY]_U
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getHibernateTemplate().execute(new HibernateCallback(){ Ji=`XsV
publicObject doInHibernate m8b-\^eP7
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(Session session)throws HibernateException { d0%Wz5Np
Criteria criteria = n) HV:8j~
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detachedCriteria.getExecutableCriteria(session); As^eL/m2L
return 9X#]Lg?b
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criteria.setProjection(Projections.rowCount Y![i=/
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()).uniqueResult(); b rDyjh
} apM)$
}, true); n
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return count.intValue(); `W1TqA
} OQg}E@LZ
} YReI|{O$c
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# M3d =
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用户在web层构造查询条件detachedCriteria,和可选的 wA,-!m
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 Y|/,*,u+
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PaginationSupport的实例ps。 9&B#@cw
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ps.getItems()得到已分页好的结果集 Ts=TaRwWf
ps.getIndexes()得到分页索引的数组 Z%I 'sWOd
ps.getTotalCount()得到总结果数 mv$gL
ps.getStartIndex()当前分页索引 8 r0;054
ps.getNextIndex()下一页索引 j&8GtE1b
ps.getPreviousIndex()上一页索引 aE:$ N#|Qa
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 5GJa+St?
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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 BGu<1$G
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一下代码重构了。 ue!4By8T
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我把原本我的做法也提供出来供大家讨论吧: criNeKa
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首先,为了实现分页查询,我封装了一个Page类: kidv^`.H$w
java代码: $JK,9G[Vu
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/*Created on 2005-4-14*/ rPifiLl A>
package org.flyware.util.page; ZJjm r,1
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/** .SWn/Kk
* @author Joa I]91{dq
*
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*/ [bBPs&7u
publicclass Page { O%} hNTS"
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/** imply if the page has previous page */ j4(f1
privateboolean hasPrePage; {^R"V ,)
A_.}-dzF
/** imply if the page has next page */ 07,&weQ
privateboolean hasNextPage; -x>2Wb~%
r!p:73L8
/** the number of every page */ U)('}u=b
privateint everyPage; M&rbXi.
aSfAu!j)
/** the total page number */ aq^OzKP?
privateint totalPage; !qs3fe<uh"
:*tFW~<*b
/** the number of current page */ ,e*WJh8k[
privateint currentPage; i%r+/D)KvG
5^{).fig
/** the begin index of the records by the current 6k ]+DbT
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query */ R)]+>M-.
privateint beginIndex; lMjeq.5nP
*UdP1?Y
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/** The default constructor */ uNvdlY]
public Page(){ Cuom_+wV&
*HQ>tvUh
} nX+c
HF
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/** construct the page by everyPage =n_>7@9l
* @param everyPage )!=X?fz,O
* */ <im<0;i&e
public Page(int everyPage){ G;^,T/q47
this.everyPage = everyPage; 3s,a%GOk
} uVZX53 ,g
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/** The whole constructor */ |k/;1.b!9(
public Page(boolean hasPrePage, boolean hasNextPage, rCdTn+O2
Pt7yYl&n7^
7,R
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int everyPage, int totalPage, UH7FIM7kX
int currentPage, int beginIndex){ fa(- &;q
this.hasPrePage = hasPrePage; -b'/}zz
this.hasNextPage = hasNextPage; n wO5<b;
this.everyPage = everyPage; F Xp_`9.zH
this.totalPage = totalPage; xHuw ?4
this.currentPage = currentPage; Zy^ wS1io
this.beginIndex = beginIndex; 8MBvp*
} bMN]co
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/** -y8>c0u
* @return SM[VHNr,-
* Returns the beginIndex. $`"$ZI6[
*/ }_9yemP
publicint getBeginIndex(){ Qa,$_,E
return beginIndex; Ihx[S!:
} ME'LZ"VT
94u~:'t>V
/** p!+bn,?G
* @param beginIndex s#)0- Zj
* The beginIndex to set. _*u$U
*/ Kq}-)
publicvoid setBeginIndex(int beginIndex){ u~1 ,88&U
this.beginIndex = beginIndex; QT[4\)
} 3ZX#6*(}2
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/** Fz@U\\94z
* @return {R5_=MG
* Returns the currentPage. 7$Pf
*/ ~5n?=
publicint getCurrentPage(){ g ~>nT>6
return currentPage; <l$ vnq
} jluv}*If
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/** X-cP'"
* @param currentPage u Uh6/=y
* The currentPage to set. C@9K`N[*
*/ p+^K$w^Cs
publicvoid setCurrentPage(int currentPage){ p}|<EL}Z9
this.currentPage = currentPage; qDjH^f
} N'I9J?e Q
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/** Ba9"IXKH
* @return OwLJS5r@<-
* Returns the everyPage. (O'O#AD
*/ 8hZc#b;
publicint getEveryPage(){ jN!sLW
return everyPage; =T#?:J#a
} =+"-8tz8FV
>*]B4Q
/** %m "9 =C
* @param everyPage s,7OoLE
* The everyPage to set. 14p{V}f3
*/ oX?~
publicvoid setEveryPage(int everyPage){ kDc/]Zb%
this.everyPage = everyPage; E=qfI>2U&
} r,wC5%&Za
3IQ-2 X--
/** $2$jV1s
* @return KZ|p_{0&
* Returns the hasNextPage. ,/UuXX
*/ |6~ Kin
publicboolean getHasNextPage(){ }\vw>iHPX@
return hasNextPage; Bx0=D:j
} 2z9N/SyN
/rv=mlpRL
/** FUZ`ST+OL
* @param hasNextPage M(W-\L
* The hasNextPage to set. #6nuiSF
*/ R5fZ}C7
publicvoid setHasNextPage(boolean hasNextPage){ M[^EHa<i
this.hasNextPage = hasNextPage; H@`lM~T[
} v|2+7N:[;
*NQsD C.J^
/** Zu/1:8x
* @return J%8hf%!ud
* Returns the hasPrePage. 'UB"z{w%
*/ ^fvx2<
publicboolean getHasPrePage(){ Ej'N!d.
return hasPrePage; }dG>_/3
} [ejl #'*5
#=I5_u
/** l1]'3]P(
* @param hasPrePage '#CYw=S+
* The hasPrePage to set. :bz;_DZP
*/ {-L}YX"Bh
publicvoid setHasPrePage(boolean hasPrePage){ wK Je^7
this.hasPrePage = hasPrePage;
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} tj[-|h
P.O/ZW>g
/** ie<m)
* @return Returns the totalPage. HkyN$1s
* M.KXDD#O
*/ %QX"oRMn0
publicint getTotalPage(){ fnudy%oo
return totalPage; YG>6;g)Zm
} NucLf6
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/** 8'[7
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* @param totalPage f}ji?p
* The totalPage to set. <al(7
*/ /Iy]DU8
publicvoid setTotalPage(int totalPage){ X7MM2V
this.totalPage = totalPage; VcYrK4
} 65P0,b6"OT
/t57!&
} D/xbF`
#Y`~(K47
7IH@oMvE
{\"x3;3!6
}'V5/>m[
上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 kx{{_w
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个PageUtil,负责对Page对象进行构造: H5B:;g@
java代码: ::lKL
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/*Created on 2005-4-14*/ D,*3w'X!K
package org.flyware.util.page; wE>\7a*P%
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import org.apache.commons.logging.Log; %D34/=(X
import org.apache.commons.logging.LogFactory; _ QI\
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/** X;+sUj8
* @author Joa ^do9*YejX;
* tH@Erh|%
*/ YR\fa Vk
publicclass PageUtil { ?6!JCQJ<
QD&`^(X1p
privatestaticfinal Log logger = LogFactory.getLog wo{gG?B
|Pax =oJ\M
(PageUtil.class); ] )\Pqn(
'?' l;#^i<
/** Y=?3 js?O
* Use the origin page to create a new page Xf]d. :
* @param page i v38p%Zm
* @param totalRecords z6\UGSL
* @return &vMb_;~B
*/ DH!~ BB;
publicstatic Page createPage(Page page, int ]IQ&>z}<
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totalRecords){ A2Ed0|B y
return createPage(page.getEveryPage(), 0R'?~`aTt
+gtbcF@rx
page.getCurrentPage(), totalRecords); 24*XL,
} v%z=ysA
)23H1
/** cf20.F{<
* the basic page utils not including exception u cW-I;"
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handler VU]`&`~J
* @param everyPage k"zv~`i'
* @param currentPage c9u`!'g`i
* @param totalRecords SsDmoEeB[
* @return page yI
*/ P* BmHz4KL
publicstatic Page createPage(int everyPage, int 6}Ci>_i4#
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currentPage, int totalRecords){ "_NN3lD)X
everyPage = getEveryPage(everyPage); qWPkT$ u
currentPage = getCurrentPage(currentPage); e\zm7_+i{
int beginIndex = getBeginIndex(everyPage, D'PI1
0t
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currentPage); kv{za4,&
int totalPage = getTotalPage(everyPage, oY3;.;'bk
^A&1^B
totalRecords); /%1ON9o>
boolean hasNextPage = hasNextPage(currentPage, Z0", !6nS
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totalPage); -zeG1gr3
boolean hasPrePage = hasPrePage(currentPage); MH\dC9%p
16( QR-
returnnew Page(hasPrePage, hasNextPage, j>" @,B g*
everyPage, totalPage, *P=VFP
currentPage, I-(zaqp@
mNTzUoZF'@
beginIndex); .[OUI
} U$A]8NZ$S
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privatestaticint getEveryPage(int everyPage){ `dN@u@[\ks
return everyPage == 0 ? 10 : everyPage; y?? XIsF
} =X:Y,?
xY(*.T9K
privatestaticint getCurrentPage(int currentPage){ 7[XRd9a5(
return currentPage == 0 ? 1 : currentPage;
Aw.qK9I
} CkQ3#L <2
g:8h|w)
privatestaticint getBeginIndex(int everyPage, int K is"L(C
Ai3*QX
currentPage){ VjZ|$k
return(currentPage - 1) * everyPage; "@0]G<H
} ENs&RZ;
-x`@6
privatestaticint getTotalPage(int everyPage, int V {ddr:]4
&d^m 1
totalRecords){ hMD|#A-<
int totalPage = 0; Z}Ft:7
oEZdd#*;
if(totalRecords % everyPage == 0) HRfYl,S,
totalPage = totalRecords / everyPage; Dwfu.ZJa
else 'AS|ZRr/
totalPage = totalRecords / everyPage + 1 ; y/ef>ZZ
E#N|wq
return totalPage; *wB1,U{
} 0gP}zM73
">,|V-H
privatestaticboolean hasPrePage(int currentPage){ Zaf:fsj>
return currentPage == 1 ? false : true; "
9wvPC ^
} [uN?
~lp\%
2*l/3VW
privatestaticboolean hasNextPage(int currentPage, h_3E)jc
paE[rS\
int totalPage){ ~1AgD-:Jz
return currentPage == totalPage || totalPage == 4-y:/8
CXx*_@}MU
0 ? false : true; SBk4_J/_
} ?(F6#"/E
#:U%mHT(_
k&vz7Q`T
} cj|80$cSA
DGn;m\B
Vl=l?A8
m6\E$;`
rCbDu&k]
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 n&qg;TT
3-qr)h
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 CMG&7(MR
*:LK8U
做法如下: li'YDtMKCY
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 ?*1uN=oI{*
;oKZ!ND
的信息,和一个结果集List: %XoiVlT@:
java代码: qHplJ "
mt+Oi70
N06OvU2>xU
/*Created on 2005-6-13*/ PI:4m%[
package com.adt.bo; O1U= X:Zl
RYQR(v
import java.util.List; uLL]A>vR
b"uu
import org.flyware.util.page.Page; .B]MpmpK
vkx7paY_
/** ~Z?TFg
* @author Joa L:pYn_
*/ Vvn2 Ep
publicclass Result { HV!m8k=6
m '|bGV
private Page page; sV{,S>s
F|o:W75
private List content; 7uS~MW
5j<mbt}
/** Pg0x/X{t
* The default constructor UXc-k
*/ 0d"[l@UU0
public Result(){ Ic"ybj`
super(); Ustv{:7v
} Q_Q''j(r6b
hk(ZM#Bh
/** hl7bzKO*w
* The constructor using fields @fZ,.2ar
* |+FubYf?$
* @param page G C),N\@Q
* @param content MSQEO4ge
*/ \:# L)
public Result(Page page, List content){ W#4 7h7M
this.page = page; H1pO!>M
this.content = content; [fya)}
} 5,Jp[bw{H{
L3u&/Tn2
/** "/*\1v9
* @return Returns the content. KQaxvU)L
*/ -LoZs
ru
publicList getContent(){ p*R;hU
return content; =r?hgGWe
} ??-[eB.
-[4T
/** (^8Y|:Tz
* @return Returns the page. _wbF>z
*/ u<7/0;D#+
public Page getPage(){ ?K$(817
return page; ~NrG`
D}
} =1FRFZI!j
I+%[d^,
/** :}L[sl\R
* @param content \+oQd=K@
* The content to set.
acajHs
*/ ="1Ind@w!
public void setContent(List content){ zsEc(
this.content = content; tzWSA-Li
} <$A
aD<A.Lhy
/** |sJ[0z
* @param page qTRsZz@
* The page to set. !_]Y~[
*/ oA7tEu
publicvoid setPage(Page page){ e&|'I"
this.page = page; T>Z<]s
} gJ{)-\
} B[Scr5|
!<";cw(q
(CL%>5V
0+ '&`Q!u
T-L||yE,h
2. 编写业务逻辑接口,并实现它(UserManager, Zi
i
Or+U@vAnk
UserManagerImpl) (t|Zn@uY
java代码: $%Kfq[Q
33q}CzK
rlLMT6r.8
/*Created on 2005-7-15*/ *&W"bOMH*
package com.adt.service; B9 uoVcW
J@'wf8Ub
import net.sf.hibernate.HibernateException; ITBE|b
Y.UFbrv
import org.flyware.util.page.Page; +'a^f5
0OE:[pR
import com.adt.bo.Result; /~?*=}c^m
n\DV3rXI9
/** 2zb"MEOS5
* @author Joa %$L{R
*/ y%T_pTcU
publicinterface UserManager { <'*LRd$1
7$=InK
public Result listUser(Page page)throws AkV#J,
3LC
vE?G7%,
HibernateException; r19
pZAc
IJ"q~r$
} H
<l7ZS:
}Y\%RA
tsjrRMR
+0Y&`{#Z
Z9|P'R(l
java代码: 0,")C5j
jLluj
&QgR*,5eo
/*Created on 2005-7-15*/ 4B.*g-L
package com.adt.service.impl; :o3N;*o>)0
y)@wjH{6
import java.util.List; GTd,n=
N6:`/f+A>T
import net.sf.hibernate.HibernateException; (<9u-HF#
K"MX!
import org.flyware.util.page.Page; =^?/+p8k
import org.flyware.util.page.PageUtil; (9a^$C*
0=YI@@n)
import com.adt.bo.Result; 1qA;/-Zr<o
import com.adt.dao.UserDAO; xJe%f\UDu
import com.adt.exception.ObjectNotFoundException; })%{AfDRF
import com.adt.service.UserManager; ]f_p8?j"
9*M,R,y
/** QXK{bxwC
* @author Joa GbI/4<)l}
*/ Z`i(qCAd(
publicclass UserManagerImpl implements UserManager { ^cWnF0)j.
{Sh ;(.u^
private UserDAO userDAO; 'w aaw_>b
RA 6w}:sq7
/** jP.dDYc
* @param userDAO The userDAO to set. "tK=+f`NM
*/ TWTb?HP
publicvoid setUserDAO(UserDAO userDAO){ m&3xJuKih
this.userDAO = userDAO; i%?* @uj
} +}AI@+
SpBy3wd
/* (non-Javadoc) sI2^Qp@O1
* @see com.adt.service.UserManager#listUser KI.hy2?e
HzsdHH(J
(org.flyware.util.page.Page) Q>z8IlJ}
*/ X?Q4} Y
public Result listUser(Page page)throws i|kRK7[6B
ca9X19NG
HibernateException, ObjectNotFoundException { bN.Pex
int totalRecords = userDAO.getUserCount(); #vlgwA
if(totalRecords == 0) L~3Pm%{@A
throw new ObjectNotFoundException Fr-SvsNFB
['D]>Ot68
("userNotExist"); ]4e;RV-B
page = PageUtil.createPage(page, totalRecords); Ib0ZjX6
List users = userDAO.getUserByPage(page); 4NIRmDEd
returnnew Result(page, users); _]*>*XfF(
} Yir
[!{
~3S~\0&|
} F*K_+
?m
4YX3+oS
w8D"CwS1Rx
C{XmVc.
K!]/(V(}
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 zZC9\V}R
.K<Q&
询,接下来编写UserDAO的代码: o\)F}j&b#=
3. UserDAO 和 UserDAOImpl: B !=F2
java代码: ]}(H0?OQR
qWKAM@
}Ys>(w
/*Created on 2005-7-15*/ '!a'ZjYyi
package com.adt.dao; 8&Y^""#e)
*C=>X193U
import java.util.List; A6iq[b]
QZ%`/\(!8_
import org.flyware.util.page.Page; x7x\Y(@
Q'mM3pq4r
import net.sf.hibernate.HibernateException; ,T8 ~L#M~
A7hVHxNJ-
/** ,$+V
* @author Joa 1\rz%E
*/ _aMPa+D=P
publicinterface UserDAO extends BaseDAO { k/gZ,
Wh2tNyS
publicList getUserByName(String name)throws usL*
x9i
A^EE32kbm
HibernateException; wtV#l4
M6-&R=78K
publicint getUserCount()throws HibernateException; f_Av3
;H.^i|_/
publicList getUserByPage(Page page)throws cXOK)g#
{9aE5kR
HibernateException; do+.aOC
6,9>g0y'NG
} 4G>H
} c}_<#I
Ev(>z-{F
Yv!a88+A8M
#!KE\OI;@5
java代码: )Z ?Ym.0/
4l45N6"
Nf"r4%M<6
/*Created on 2005-7-15*/ qF-@V25P
package com.adt.dao.impl; q Xe8Kto
k<{{*
import java.util.List; Jrpx}2'9:a
o;R2p $
import org.flyware.util.page.Page; rOOT8nkR#
r_6ZO&
import net.sf.hibernate.HibernateException; 0h\smqm
import net.sf.hibernate.Query; Hi1JLW,
[>%xd)8.c
import com.adt.dao.UserDAO; Z>W g*sZy)
#"\gLr_:m
/** 364`IC( a
* @author Joa doy`C)xI
*/ )MchsuF<
public class UserDAOImpl extends BaseDAOHibernateImpl W_8wed:b
TS9|a{j3!
implements UserDAO { PFne+T!2F
(/j/>9iro
/* (non-Javadoc) h*$y[}hDuv
* @see com.adt.dao.UserDAO#getUserByName {Um)15K
es&vMY
(java.lang.String) ;J2z p*|
*/ f;gw"onx8F
publicList getUserByName(String name)throws ?Yk.$90
?ztkE62t
HibernateException { j=aI9p
String querySentence = "FROM user in class JYd 'Jp8bP
W=vP]x
>J
com.adt.po.User WHERE user.name=:name"; i?g5_HI
Query query = getSession().createQuery iQ
fJ
3ojlB |Z
(querySentence); giIWGa.a+
query.setParameter("name", name); Sf7\;^
return query.list(); SO(NVJh
} _EMwm&!
p@5`&Em,
/* (non-Javadoc) SB|Qa}62
* @see com.adt.dao.UserDAO#getUserCount() h=kh@},
*/ ;y\IqiA{o
publicint getUserCount()throws HibernateException { sy"^?th}b
int count = 0; S` ;?z
String querySentence = "SELECT count(*) FROM l6kWQpV
F,MO@&ue"
user in class com.adt.po.User"; Q[pV!CH
Query query = getSession().createQuery ,Pjew%
.my0|4CQ#@
(querySentence); @&:ar
count = ((Integer)query.iterate().next >>o dZL
[uq$5u
()).intValue(); s4SG[w!d
return count; -}=%/|\FG
} I@%t.%O Jp
cmg^J
/* (non-Javadoc) Uo>]sNP~
* @see com.adt.dao.UserDAO#getUserByPage TXk?#G\o
6qaQ[XTxf
(org.flyware.util.page.Page) aL%AQB,
*/ 'BPp ]R#{
publicList getUserByPage(Page page)throws ul2")HL];
M&Uj^K1
HibernateException { pxf$1
String querySentence = "FROM user in class ); dT_
F\k+[`%{
com.adt.po.User"; R_7 d@FQ1
Query query = getSession().createQuery xJZ>uTN
G *;a^]-
(querySentence); .!,z:l$Kh
query.setFirstResult(page.getBeginIndex()) q+]h=:5=I
.setMaxResults(page.getEveryPage()); h!ZV8yMc
return query.list(); T {Uc:Z
} g(J&m<I
C
#6dC0
} ,JN8f]a^"g
&2zq%((r
tAte)/0C
p2udm! )J
qt
2d\f
至此,一个完整的分页程序完成。前台的只需要调用 [7S} g
<l9-;2L4
userManager.listUser(page)即可得到一个Page对象和结果集对象 o1Q7Th
:!b'Vk
的综合体,而传入的参数page对象则可以由前台传入,如果用 p>;_e(
P2'DD 3
webwork,甚至可以直接在配置文件中指定。 .j>hI="b
@kU@N?5e
下面给出一个webwork调用示例: m"jV}@agX
java代码: z`FCs,?K
FMkzrs
mAW,?h
/*Created on 2005-6-17*/ *9c!^$V
package com.adt.action.user; o b|BXF
{=-\|(Bx
import java.util.List; mJ`A_0
iVTGF<
import org.apache.commons.logging.Log; )V:]g\t
import org.apache.commons.logging.LogFactory; 3UQ;X**F
import org.flyware.util.page.Page; 1,~SS
Cp]"1%M,
import com.adt.bo.Result; ADk8{L{UU
import com.adt.service.UserService; 1=a>f"cyf
import com.opensymphony.xwork.Action; z2hc.29t
!i%"7tQ3$
/** 3LTcEd
* @author Joa M7+h(\H]2
*/ @L:>!<
publicclass ListUser implementsAction{ TkO[rAC
zC:wNz@zK
privatestaticfinal Log logger = LogFactory.getLog ]B]*/
Cssl{B
(ListUser.class); 4[-*~C|W5
_fP&&}
private UserService userService; /q$,'^.A
STw#lU) %(
private Page page; [j:[
~/ilx#d
privateList users; [kgdv6E
wL^%w9q-
/* pdEiqLhH
* (non-Javadoc) -}6xoF?
* i^!ez5z
* @see com.opensymphony.xwork.Action#execute() ?cEskafb>
*/ 2kUxD8BcN
publicString execute()throwsException{ %9#gB
Result result = userService.listUser(page); _:B1_rz7,
page = result.getPage(); !'*csg
users = result.getContent(); Q9&kJ%Mo
return SUCCESS; FG!X"<he
} BMIyskl=i
yj(vkifEB
/** n7YEG-J
* @return Returns the page. 3o|I[!2.
*/ GzTq5uU&
public Page getPage(){ M}wXJ8aF?
return page; vHE^"l5 v
} eVcANP
}/,CbKi,+
/** 35x 0T/8
* @return Returns the users. DK&h
eVIoZ
*/ ow' lRHZ
publicList getUsers(){ Zf>^4_x3P
return users; nD2,!71
} N=)z
:p4 "IeKs
/** 35*\_9/#
* @param page 'snYu!`z
* The page to set. VNtPKtx\
*/ HOp-P8z
publicvoid setPage(Page page){ Jj^GWZRu
this.page = page; !"TZ:"VZU
} 8Z2.`(3c[
/+3a n9h
/** S?0)1O
* @param users Ih[+K#t+E
* The users to set. "XLe3n
*/ :;!\vfZbU
publicvoid setUsers(List users){ e|r0zw S
this.users = users; D["MUB4l
} Sb:T*N0gS
)hj|{h7
/** @)8]e
S7
* @param userService mEuHl>
* The userService to set. ,`8Y8
*/ [W,-1.$!dM
publicvoid setUserService(UserService userService){ - n6jG}01b
this.userService = userService; XDD<oo
} *xM/;)
} [[)_BmS5r
m^{
xd2
e^$j5jV
WIh@y2&R
ER{3,0U
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, Cj;/Uhs
K.SeK3(
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 .%0ne:5
<V_7|)'/A
么只需要: RwTzz]
M
java代码: 5`E))?*"Pe
^i:\@VA:
[D'Gr*5~{
<?xml version="1.0"?> q3'o|pp
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork $~'Tf>e
=`I?mn&
1.0//EN" "http://www.opensymphony.com/xwork/xwork- s!6=|SS7
;~sr$6
1.0.dtd"> 04y!\
o+g4p:Mf
<xwork> h#3m4<w(9
'0+$ m=
<package name="user" extends="webwork- ]RFdLV?
iY.eJlfH
interceptors"> $ehg@WK}.
->yeJTsE9
<!-- The default interceptor stack name GH3#E*t+[
X_70]^XL
--> H|+tC=]4IZ
<default-interceptor-ref h}=M^SL
t^@T`2jL
name="myDefaultWebStack"/> =%h~/,
B2hfD-h,>
<action name="listUser" {~GR8
U
}#b
%"I0
class="com.adt.action.user.ListUser"> 1| xN%27>
<param V8'`nuC+
~5t?C<wo
name="page.everyPage">10</param> _9h.Gt
<result A'DVJ9%xB
9 )Yw
:
name="success">/user/user_list.jsp</result> 56s*A*z$
;
</action> <7gMl
cjg=nTsBA
</package> `Ei"_W
#O</\|aH)i
</xwork> 5V|tXsy:
A!;meVUs
C.E[6$oVc
UpeQOC
R:11w#m7w
JI(8{ f
这样就可以通过配置文件和OGNL的共同作用来对page对象设置初值 ~W!sxM5(*
(ZDRjBth[
了。并可以通过随意修改配置文件来修改每页需要显示的记录数。 (G:$/fK
o: TO[
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 <jfi"SJu
W*gu*H^s~
x2;92I{5C,
Q9{%
iugTXZ(
我写的一个用于分页的类,用了泛型了,hoho BB9Z?}
C)Mh
java代码: /8lGP!z
&`{%0r[UD#
.hnGHX
package com.intokr.util; ?:~ `?
bc%7-%
import java.util.List; W +C\/
taw
#r
/** u.R:/H<>~
* 用于分页的类<br> bNj| GIf
* 可以用于传递查询的结果也可以用于传送查询的参数<br> "@DCQ
* &!a[rvtZ+
* @version 0.01 (q*Za
* @author cheng P6dIU/w
*/ ^<7)w2ns
public class Paginator<E> { yin"+&<T
privateint count = 0; // 总记录数 Jy{A1i@4~s
privateint p = 1; // 页编号 CZt)Q4
privateint num = 20; // 每页的记录数 2 ES .)pQ
privateList<E> results = null; // 结果 qK#\k@E
qbpvTTF
/** "3W!p+W
* 结果总数 ~\(U&2t
*/ 3@_je)s
publicint getCount(){ Xb5n;=)
return count; 3L/>=I{5
} ZoF\1C ^
K>"M#T
publicvoid setCount(int count){ rer=o S
this.count = count; GjfY
} S2w|\"
6uOR0L
/** hT#[[md"
* 本结果所在的页码,从1开始 k5P&F
* 8S&`
* @return Returns the pageNo. s+$l.aIO!
*/ P] ouLjyq
publicint getP(){ ~W_m<#K(
return p; 5JBenTt
} (Rve<n6{A
P
BpjE}[Q
/** o'?Y0Wt
* if(p<=0) p=1 >x eKO2o
* 120<(#
* @param p !Z`~=n3bk
*/ gQCkoQi:j
publicvoid setP(int p){ z+C>P4c-y&
if(p <= 0) .yd{7Te
p = 1; _A;jtS)SY
this.p = p; a{mtG{Wc
} y9?B vPp+
s
'u6Ep/V
/** /xWkP{
* 每页记录数量 (&=-o(
*/ eo24I0`N
publicint getNum(){ K, WNM S
return num; uI}S9
} !-m(1
=)
$a>N
/** QS4sSua
* if(num<1) num=1 b54<1\&
*/ ;$wS<zp6
publicvoid setNum(int num){ Ks(+['*S
if(num < 1) fILINW{Yk)
num = 1; }5z6b>EI9a
this.num = num; k"uqso/
} )O#]Wvr
bjmUU6VLT
/** BuCU_/H
* 获得总页数 Z2_eTC
u
*/ Xp[[ xV|
publicint getPageNum(){ (wdE@/V
return(count - 1) / num + 1; F42r]k
} v7&e,:r2E@
cpF\^[D
/** dE7 kd=.o
* 获得本页的开始编号,为 (p-1)*num+1 [=z1~dXKb
*/ KJo[!|.
publicint getStart(){ 2Vxr
return(p - 1) * num + 1; dQVV0)z
} 4_TxFulX.
8p,q9Ey
/** >9'G>~P~I=
* @return Returns the results. T;XEU%:LK
*/ G"T)+!6t
publicList<E> getResults(){ pk%I98! Jy
return results; !@{_Qt1
} IHZ WNT2
[u;]J*
public void setResults(List<E> results){ j0B, \A
this.results = results; 0}2Uj>!i
} _A|1_^[G(
V@&zn8?
public String toString(){ z9}rT<hy
StringBuilder buff = new StringBuilder Z$ Fh4
GMU.Kt
(); S5*wUd*p#
buff.append("{"); :~3sW< PR
buff.append("count:").append(count); "aHY]E{
buff.append(",p:").append(p); *[*LtyCQt4
buff.append(",nump:").append(num); */sVuD^b`
buff.append(",results:").append Vy.A`Hz
6^F"np{w
(results); JP)/
O!
buff.append("}"); mq`N&ABO!K
return buff.toString(); zhY VMQ
} QDYS}{A:V
tQ_;UQlX
} `e .;P
;W]NT4p
7Oe |:Z