Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 PNSZ
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 N/A.1W
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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 .)W'{2J-
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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 Ks.pb !r
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分页支持类: _LV;q! /j
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java代码: ^ ~HV`s
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package com.javaeye.common.util; Aw)='&;^z
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import java.util.List; L;=<d
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publicclass PaginationSupport { T`{W$4XS
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publicfinalstaticint PAGESIZE = 30; b$P=rIB
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privateint pageSize = PAGESIZE; (( 0%>HJ{~
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privateList items; d%Zt]1$
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privateint totalCount; lHwQ'/r
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privateint[] indexes = newint[0]; k,S'i#4q4
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privateint startIndex = 0; Zqke8q
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public PaginationSupport(List items, int :]Jwcp
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totalCount){ 2H8,&lY.p
setPageSize(PAGESIZE); y&NO[
setTotalCount(totalCount);
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setItems(items); ajuwP1I
setStartIndex(0); xI}h{AF7
} \$ L2xd
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public PaginationSupport(List items, int eN@V?G26K
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totalCount, int startIndex){ \+mc
setPageSize(PAGESIZE); O0#wM-M
setTotalCount(totalCount); aDuO!?Cm
setItems(items); 3k;*xjv6@
setStartIndex(startIndex); /i|T \
} zFh
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public PaginationSupport(List items, int f{[U->#^
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totalCount, int pageSize, int startIndex){ |a#4
setPageSize(pageSize); PZ~uHX_d>
setTotalCount(totalCount); !']=7It{
setItems(items); r*<)QP^B~
setStartIndex(startIndex); E~xK1x"
} _B)LRD+Hj
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publicList getItems(){ mXT{)pU
return items; pPm[<^\# S
} r'M|mQ$s>
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publicvoid setItems(List items){ Fxy-_%a
this.items = items; gT*0WgB
} Rm 1obP
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publicint getPageSize(){ %B`MO-
return pageSize; "BZ6G`
} 8'?V5.6?|~
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publicvoid setPageSize(int pageSize){ wxEFM)zr
this.pageSize = pageSize; |i5A
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} @ 'rk[S}A
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publicint getTotalCount(){ 0PD]#.+
return totalCount; 6,)!\1k
} 0\O*\w?
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publicvoid setTotalCount(int totalCount){ o0^'xVv
if(totalCount > 0){ 0l !%}E
this.totalCount = totalCount; 7yxZe4~|#
int count = totalCount / !Gsr* F{.
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pageSize; &=5
if(totalCount % pageSize > 0) Ks:~Z9r}
count++; 2 628 c`
indexes = newint[count]; !1K<iz_8
for(int i = 0; i < count; i++){ J:Uf}!D
indexes = pageSize * $A,fO~
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} E6|!G
}else{ 'm9f:iTr
this.totalCount = 0; 6?Ul)'
} (nfra,'
} ivsp):W
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publicint[] getIndexes(){ l j*ELy
return indexes; [4sI<aH
} LS@[O])$'
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publicvoid setIndexes(int[] indexes){ K <7#;
this.indexes = indexes; GJW+'-f
} p"f=[awp
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publicint getStartIndex(){ )nU%}Z
return startIndex; ]YYjXg}%
} #k5WTcE
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publicvoid setStartIndex(int startIndex){ Y ::\;s
if(totalCount <= 0) YP{)jAK
this.startIndex = 0; iD,iv
elseif(startIndex >= totalCount) Hi #'h
this.startIndex = indexes fBS`b[x
B4 5B`Ay
[indexes.length - 1]; /*s:ehj
elseif(startIndex < 0) n-[J+DdB
this.startIndex = 0; 7q?u`3l
else{ =SPuOy8
this.startIndex = indexes HubSmbS1
CLU !/J$!
[startIndex / pageSize]; Cr|v3Y#h'
} 2)]C'
}
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publicint getNextIndex(){ } r^@Xh
int nextIndex = getStartIndex() + ?n)r1m
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pageSize; 9k =-8@G9
if(nextIndex >= totalCount) {Buoo~
return getStartIndex(); .CH0PK=l
else 0.S].Y[
return nextIndex; z5IHcZ
} G%~=hEK0
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publicint getPreviousIndex(){ 6J0HaL
int previousIndex = getStartIndex() - -IhFPjQ
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pageSize; %0T/>:1[E
if(previousIndex < 0) e&Z}struE
return0; "GoNTM5h
else g/,fjM_
return previousIndex; 49n.Gc
} CK[2duf^~
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} 1L1_x'tT%
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抽象业务类 X1G[&
java代码: 7onMKMktM%
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/** 6dTq&GZ\
* Created on 2005-7-12 {H s""/sb
*/ ;:1d<Q|
package com.javaeye.common.business; Y W_E,A>h
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import java.io.Serializable; m&o}qzC'y
import java.util.List; UI|L;5
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import org.hibernate.Criteria; jfF,:(P%W
import org.hibernate.HibernateException; tVQfR*=
import org.hibernate.Session; t ]{qizfOB
import org.hibernate.criterion.DetachedCriteria; SzkF-yRd
import org.hibernate.criterion.Projections; nW+rJ
import cAC2Xq
b1{~j]"$L
org.springframework.orm.hibernate3.HibernateCallback; KTxdZt
import Ga~N7
%~P]x7%|
org.springframework.orm.hibernate3.support.HibernateDaoS vFY/o,b \
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upport; E(tdL,m'
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import com.javaeye.common.util.PaginationSupport; g.aNITjP
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public abstract class AbstractManager extends t+Mr1e
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HibernateDaoSupport { :xZ/c\
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privateboolean cacheQueries = false; _v4TyJ
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privateString queryCacheRegion; _m;cX!+~_
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publicvoid setCacheQueries(boolean >JS\H6
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cacheQueries){ vq_W zxaG
this.cacheQueries = cacheQueries; o1"U'y-9V
} @I}:HiF
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publicvoid setQueryCacheRegion(String g#`(&
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queryCacheRegion){ '[JrP<~^o
this.queryCacheRegion = aAO[Y"-:,Y
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queryCacheRegion; 1JgnuBX"
} 7M}T^LC
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publicvoid save(finalObject entity){ l3n* b6
getHibernateTemplate().save(entity); ~ $#DB@b
} srx`"
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publicvoid persist(finalObject entity){ e%x$Cb:znn
getHibernateTemplate().save(entity); X;sl?8HG!<
} tc@v9`^_
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publicvoid update(finalObject entity){ *r p@`W5
getHibernateTemplate().update(entity); N::_JH?^=
} S4s\ tA<
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publicvoid delete(finalObject entity){ 9cFFQM|o
getHibernateTemplate().delete(entity); ^C>i(j&
} /YHBhoat
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publicObject load(finalClass entity, Bcrd}'no
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finalSerializable id){ 8U\;N
return getHibernateTemplate().load -`]B4Nt6
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(entity, id); sBS\S
} B9iH+
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publicObject get(finalClass entity, /-E>5 w U
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finalSerializable id){ $q
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return getHibernateTemplate().get "KOLRJ@
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(entity, id); ?F*gFW_k
} ex $d~
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publicList findAll(finalClass entity){ [[JwHM8H&
return getHibernateTemplate().find("from gsc/IUk
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" + entity.getName()); #$K\:V+ 4
} *ky5SM(NR
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publicList findByNamedQuery(finalString {\`#,[
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namedQuery){ p}R)qz-=5U
return getHibernateTemplate ?OYu BZF
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().findByNamedQuery(namedQuery); [@#P3g\:>W
} r&0v,WSp&S
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publicList findByNamedQuery(finalString query, 2aW&d=!ZV
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finalObject parameter){ ?&)<h_R4p
return getHibernateTemplate 0u
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().findByNamedQuery(query, parameter); SR%h=`t
} s=~r. x
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publicList findByNamedQuery(finalString query, VZb0x)w
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finalObject[] parameters){ u_e}m>[S
return getHibernateTemplate Z)|*mJ
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().findByNamedQuery(query, parameters); >LFhu6T
} ~k+-))pf
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publicList find(finalString query){ b0tr)>d
return getHibernateTemplate().find m-5Dbx!j
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(query); 4B-v\3Ff
} I Vq9z
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publicList find(finalString query, finalObject 5=.,a5
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parameter){ "npj%O<bd
return getHibernateTemplate().find 9W5vp:G
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(query, parameter); +<Uc42i7n
} ?#rDoYt/Sx
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public PaginationSupport findPageByCriteria B+*F?k[
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(final DetachedCriteria detachedCriteria){ i=o<\{iV:
return findPageByCriteria o\g",O4-
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); *'QD!Tc
} v /G,
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public PaginationSupport findPageByCriteria 4Xe3PdE
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(final DetachedCriteria detachedCriteria, finalint ^$6EO)<
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startIndex){ n>+M4Zb
return findPageByCriteria {&4+W=0
n
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(detachedCriteria, PaginationSupport.PAGESIZE, b9%hzD,MR
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startIndex); 2Af1-z^^K
} cIw)ScY
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public PaginationSupport findPageByCriteria <I&X[Sqp
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(final DetachedCriteria detachedCriteria, finalint #:v|/2
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pageSize, f}Mc2PQ-
finalint startIndex){ ("}TW-r~
return(PaginationSupport) V[(zRGa{
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getHibernateTemplate().execute(new HibernateCallback(){ HKP<=<8/O
publicObject doInHibernate }~:`9PV)Z%
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(Session session)throws HibernateException { cD YKvrPY
Criteria criteria = $GSn#} yz
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detachedCriteria.getExecutableCriteria(session); _<+!
int totalCount = 4@u*#Bp`|
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((Integer) criteria.setProjection(Projections.rowCount Z_zN:BJ8L
,_!pUal
()).uniqueResult()).intValue(); K pDK Ii
criteria.setProjection ey _3ah3x
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(null); $>hPB[ [
List items = Y^M3m'd?
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criteria.setFirstResult(startIndex).setMaxResults _U?
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(pageSize).list(); mp*&{[XoVC
PaginationSupport ps = az*c0Z<pl
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new PaginationSupport(items, totalCount, pageSize, W;4rhZEgd
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startIndex); eGkB#.+J!
return ps; 7y5`YJ}!
} _D1Uc|
}, true); p[2`H$A
} )"/.2S;
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public List findAllByCriteria(final dY5 m) ?
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DetachedCriteria detachedCriteria){ { 0RwjPYp
return(List) getHibernateTemplate *|{1`{8n
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().execute(new HibernateCallback(){ oJ734v [X
publicObject doInHibernate RZoSP(6
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(Session session)throws HibernateException { 9AF%Y:y
Criteria criteria = ?41bZ$j
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detachedCriteria.getExecutableCriteria(session); cc- liY"
return criteria.list(); \f\CK@
}
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}, true); i=T!4'Zu
} `k2YH?
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public int getCountByCriteria(final 4zKmoYt
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DetachedCriteria detachedCriteria){ ##!idcC
Integer count = (Integer) {P')$f)
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getHibernateTemplate().execute(new HibernateCallback(){ 7IkNS
publicObject doInHibernate ~+|Vzm|S}
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(Session session)throws HibernateException { o]/*YaB2>
Criteria criteria = AK$&'t+$}7
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detachedCriteria.getExecutableCriteria(session); K93L-K^J
return $0 ]xeD0X
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criteria.setProjection(Projections.rowCount
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3D 4-Wo4
()).uniqueResult(); MTXh-9DA
} 5<U:Yy
}, true); Qe4O N3X!
return count.intValue(); gZq_BY_U
} 41uiW,
} O]_a$U*6
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用户在web层构造查询条件detachedCriteria,和可选的 . n[;H;
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 B SH2Kq
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PaginationSupport的实例ps。 ~aPe?{yIUa
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ps.getItems()得到已分页好的结果集 %>'Zy6C<j
ps.getIndexes()得到分页索引的数组 a\-AGG{2/X
ps.getTotalCount()得到总结果数 8;Zz25*
ps.getStartIndex()当前分页索引 uwl_TDc>%
ps.getNextIndex()下一页索引 y>^FKN/
ps.getPreviousIndex()上一页索引 fHK.q({Qc
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 D*&#}c,*
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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 J6J">
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一下代码重构了。 k?Kt*T
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我把原本我的做法也提供出来供大家讨论吧: t!-\:8n
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首先,为了实现分页查询,我封装了一个Page类: nuH=pIq6x
java代码: ''dS{nQs
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/*Created on 2005-4-14*/ 3n,jrX75u
package org.flyware.util.page; qv^P
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/** "1$X5?%
* @author Joa GKc?
* >?O?U=:<
*/ $Qz<:?D
publicclass Page { 7Kf
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/** imply if the page has previous page */ R_D&"&
privateboolean hasPrePage; 0!-'4+"
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/** imply if the page has next page */ 5vFM0
privateboolean hasNextPage; 9wlp
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/** the number of every page */ *I!R0;HT
privateint everyPage; egK~w8`W%
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/** the total page number */ ?q7MbQw
privateint totalPage; svx7
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/** the number of current page */ v%$l(
privateint currentPage; 6cd!;Ca
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/** the begin index of the records by the current @0]w!q
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query */ veuX/>!
privateint beginIndex; j,Mbl"P
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/** The default constructor */ #]dq^B~~
public Page(){ \6 1H(,
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} X~UL$S;
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/** construct the page by everyPage c(uDkX
* @param everyPage w[F})u]E
* */ ]isq}Qv~
public Page(int everyPage){ e]nP7TIU
this.everyPage = everyPage; )H @<A93
} 'Kk/
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/** The whole constructor */ 9i U/[d
public Page(boolean hasPrePage, boolean hasNextPage, KTt+}-vP^
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int everyPage, int totalPage, @D=B5f@(o
int currentPage, int beginIndex){ yKuZJXGVo
this.hasPrePage = hasPrePage; lX%-oRQ/os
this.hasNextPage = hasNextPage; VH4wsEH]
this.everyPage = everyPage; L){V(*K '
this.totalPage = totalPage; =xDxX#3
this.currentPage = currentPage; @`)>-k
this.beginIndex = beginIndex; z:Tj0<A'
} U#[T!E
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/** CVvl &on
* @return I{[}1W3]W
* Returns the beginIndex. 4i.&geXA.
*/ Op8Gj
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publicint getBeginIndex(){ 6eUGE 4NF(
return beginIndex; ZnJJ-zP
} j94~cYV
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/** xOPQ~J|z
* @param beginIndex T59FRX
* The beginIndex to set. 2q]ZI
*/ -~aG_Bp!($
publicvoid setBeginIndex(int beginIndex){ QVRQUd
this.beginIndex = beginIndex; W!T[
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} A4|7^Ay
9(qoME}>=
/** Y'jgp Vt
* @return 5x|$q kI
* Returns the currentPage. %]Nm'"Y`U
*/ /s%-c!o^
publicint getCurrentPage(){ P`O`MwEAf
return currentPage; Ym"^Ds}
} v(R^LqE
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/** JL!^R_b&c
* @param currentPage g]JRAM
* The currentPage to set. rXzq:
*/ Tc!n@!RA|
publicvoid setCurrentPage(int currentPage){ _.R]K$U
this.currentPage = currentPage;
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} !<=(/4o&P
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/** cAGM|%
* @return olr#3te
* Returns the everyPage. ctHQZ#.[(
*/ 9>0OpgvC(
publicint getEveryPage(){ wSCI?
return everyPage; fQ"Vx!
} 9015PEO
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/** <+r~?X_
* @param everyPage p
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* The everyPage to set. !5h-$;
*/ Ac{Tq iIv
publicvoid setEveryPage(int everyPage){ g18zo~LZ
this.everyPage = everyPage; z>0$SBQ-
} =bP<cC=3b
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/** Z_dL@\#|
* @return O(-6Zqk8Q
* Returns the hasNextPage. 8kSyT'kC%
*/ >EA\KrjW
publicboolean getHasNextPage(){ etX(~"gG_
return hasNextPage; I(kEvfxc"
} Il>o60u1
yxT}hMa
/** a%a0/!U[
* @param hasNextPage AqQ5L>:Gq
* The hasNextPage to set. 7&HcrkP]
*/ ~.J*_0~Ze
publicvoid setHasNextPage(boolean hasNextPage){ w(Tr,BFF
this.hasNextPage = hasNextPage; 7rbw_m`12-
} NOoF1kS+
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/** ts_|7Ev
* @return @c"s6h&
* Returns the hasPrePage. ME!P{ _/
*/ vA ZkT"
publicboolean getHasPrePage(){ `-cw[@uD
return hasPrePage; XV4aR3n{Q
} "X!1^)W-8
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/** ~#VDJ[Z
* @param hasPrePage B<Cg_C
* The hasPrePage to set. 2*cc26o
*/ 7I]?:%8h
publicvoid setHasPrePage(boolean hasPrePage){ @q>#]8
this.hasPrePage = hasPrePage; %[~g84@
} FL^t}vA
9C Ki$L
/** wL]#]DiE
* @return Returns the totalPage. bUM4^m
* E+e),qsbO
*/ "Y5 :{Kj
publicint getTotalPage(){ Jy"\_Vvl
return totalPage; _*{Lha
} U7g,@/Qx
9&Y|,&W
/** Z-_Xt^N
* @param totalPage ]B~(yh
* The totalPage to set. aR@+Qf
*/ c3c3T`B
publicvoid setTotalPage(int totalPage){ ^5?|Dj
this.totalPage = totalPage; {%P2.:
} ]mNsG0r6
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} =(P$P
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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 3,*A VcQA
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个PageUtil,负责对Page对象进行构造: luac
java代码: P\{s C6E
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/*Created on 2005-4-14*/ '^7UcgugB
package org.flyware.util.page; y@2"[fo3~
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import org.apache.commons.logging.Log; hBaG*J{
import org.apache.commons.logging.LogFactory; hPGDN\#LD
N:#$S$
/** Z0'LD<
* @author Joa ePaC8sd0
* 3A~<|<}t
*/ ]-a/)8
publicclass PageUtil { n+<
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privatestaticfinal Log logger = LogFactory.getLog qx*b\6Rt
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(PageUtil.class); 4OO^%`=)M'
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/** Zn Rj}y
* Use the origin page to create a new page Ky8,HdAq
* @param page .A6pPRy e
* @param totalRecords Q.V@Sawe5
* @return -=UvOzw
*/
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publicstatic Page createPage(Page page, int pa?AKj]
@(N}
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totalRecords){ Ro<5c_k
return createPage(page.getEveryPage(), Hl{ul'o
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page.getCurrentPage(), totalRecords); cf"!U+x
} 8 K)GH:a
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/** BV/ ^S.~
* the basic page utils not including exception H
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handler Q4S:/"*v8
* @param everyPage "Z&_*F.[O
* @param currentPage V;)+v#4{
* @param totalRecords f/0k,~,*
* @return page K9nW"0>
*/ d]sg9`
publicstatic Page createPage(int everyPage, int <RH%FhT
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currentPage, int totalRecords){ mT|r:Yr:
everyPage = getEveryPage(everyPage); GGZ9DC\{
currentPage = getCurrentPage(currentPage); 5s4x%L (~}
int beginIndex = getBeginIndex(everyPage, I?\P^f
6~?yn-Z
currentPage); :zO;E+s
int totalPage = getTotalPage(everyPage, 8W7ET@`
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totalRecords); ).Iifu|ks
boolean hasNextPage = hasNextPage(currentPage, mOyNl
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totalPage); )lU ocm
boolean hasPrePage = hasPrePage(currentPage); NNJQDkO-I
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returnnew Page(hasPrePage, hasNextPage, x%W~@_
everyPage, totalPage, ox";%|PP1
currentPage, q!h'rX=_-
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beginIndex); u,`V%J?vW
} tv]9n8v
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privatestaticint getEveryPage(int everyPage){ 4>B=k
return everyPage == 0 ? 10 : everyPage; 3YUF\L]yyw
} Vy=+G~
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privatestaticint getCurrentPage(int currentPage){ IRv/[|"L
return currentPage == 0 ? 1 : currentPage; o nv0gb/J
} <0Gk:NB,
0juP"v$C>
privatestaticint getBeginIndex(int everyPage, int Udjn.D
3?!c<^"e
currentPage){ /}eb1o
return(currentPage - 1) * everyPage; Kz]\o"K
} $L ]M3$\9
%qVD-Jln
privatestaticint getTotalPage(int everyPage, int Tx'anP
ezm*9Jc~p
totalRecords){ fP\*5|7%R
int totalPage = 0; oGt2n:
{817Svp@
if(totalRecords % everyPage == 0) .`&k`
totalPage = totalRecords / everyPage; 'Awd:Aed5
else TeJ=QpGW2
totalPage = totalRecords / everyPage + 1 ; =66'33l2
"5\6`\/
return totalPage; }+)q/]%
} 8>I4e5Ym
=&: |a$C
privatestaticboolean hasPrePage(int currentPage){ _.m|Ml,`{
return currentPage == 1 ? false : true; idjk uB(6
} :"K9(XKKU
,OMdLXr
privatestaticboolean hasNextPage(int currentPage, |NWHZo
]KUeSg|
int totalPage){ ?ihRt+eR~
return currentPage == totalPage || totalPage == z6Nz)$!_i
nM!_C-yX
0 ? false : true; p$Floubh]
} CX]L'
dvAz}3p0]
m:9|5W
} xd+aO=)Td
"z*?#&?,
!2.eJ)G
E>u U6#v
r( bA>L*mk
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 AO(zl*4
R)=){SI:1)
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 7GJcg7s*T
D]WrPWL8v
做法如下: n8z++T&
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 P9jSLM
/1xBZfrN
的信息,和一个结果集List: E!=Iz5
java代码: 1%";|
ZsP>CELm@
0~Xt_rN](
/*Created on 2005-6-13*/ UC.kI&A
package com.adt.bo; G#1W":|`
KppYe9?
import java.util.List; @z`eqG,']
5eM{>qr}
import org.flyware.util.page.Page; x+[ATZ([
~1nKL0C6u
/** nZEew.T:6
* @author Joa UMK9[Iy$<M
*/ Us%g&MWdpb
publicclass Result { 1'1>B
7zowvE?#
private Page page; u>*qDr*d
~G.MaSm
private List content; #9{2aRCJ
yqP=6
/** >1` '5A}s
* The default constructor |*l^<= =
*/ dt/-0~U
public Result(){ &%u m#XE
super(); lWBewnLKE
} _\{/#J;lN
3jHE,5m
/** S#T u/2<}
* The constructor using fields }#&L
* i9T<(sdK+
* @param page v<mSd2B*
* @param content d?V/V'T[
*/ %\~U>3Q
public Result(Page page, List content){ 2#s8Dxt
this.page = page; L XTtV0F
this.content = content; VHv L:z
} 46~nwi$,^
}nSu7)3$B
/** [&(~1C|C
* @return Returns the content. 3 Zwhv+CP[
*/ 1-Dw-./N
publicList getContent(){ K#VGG,h7Y
return content; 8/;@4^Ux
} ]@ }o"Td
^oNcZK>
/** 3ug~m-_
* @return Returns the page. >:BgatyPH
*/ q_[`PYT
public Page getPage(){ 9WV8ZP
return page; d<E2=WVB6
} 4
[]!Km
_,igN>
/** fUPYCw6F
* @param content {aUv>T"c
* The content to set. QSwT1P'U
*/ TP)o0U
public void setContent(List content){ P/Y)Yx_(
this.content = content; Mhc5<~?
} ,uO_C(G/i
.')^4\
/** fA=Lb^,M
* @param page J/PK#<
* The page to set. 15%6;K?b
*/ uA cvUN-@
publicvoid setPage(Page page){ ==trl#kQ%%
this.page = page; 3}C-Hg+gt
} fJe5
i6`(
} v?n# C
Y@qugQM>
B[2t.d;h
@moaa} 1
D&]xKx
2. 编写业务逻辑接口,并实现它(UserManager, 4ywtE}mp
l>J%Q^
UserManagerImpl) K<WowU
java代码: "#iO{uMWb
9NZq
k
x@:98P
/*Created on 2005-7-15*/ NdRE,HWd?$
package com.adt.service; A;f)`i0l,
v
"[<pFj^
import net.sf.hibernate.HibernateException; \Rha7O
>y!O_@>z
import org.flyware.util.page.Page; x}x )h3e
G/w@2lYx
import com.adt.bo.Result; KvI/!hl\
S(rnVsW%Ki
/** T8x /&g''
* @author Joa T~4HeEG>uH
*/ 9_Z_5w;h
publicinterface UserManager { t{B6W)q
f/Z-dM\e
public Result listUser(Page page)throws =c]We:I
VP7LKfv
HibernateException; u!fZ>kS
dN){w _
} vi[~Qt
=w:H9uj6F
Svs&?B\}{6
0t*PQ%
ZY;g)`E1
java代码: s"8z q;)
Lf{pTxKr
"`'+@KlE
/*Created on 2005-7-15*/ "'>fTk_
package com.adt.service.impl; $0]5b{i]
O_5;?$[m
import java.util.List; ?pA_/wwp
DvA#zX[
import net.sf.hibernate.HibernateException; 3;!a'[W&p
z,VXH ?.Zo
import org.flyware.util.page.Page; Yt r*"-
import org.flyware.util.page.PageUtil; % 5BSXAc
>as+#rz1p
import com.adt.bo.Result; dp3TJZ+U
import com.adt.dao.UserDAO; !
e?=g%(
import com.adt.exception.ObjectNotFoundException; *6v5JH&K
import com.adt.service.UserManager; .0|_J|{
{4%ddJn[.)
/** gUp9yV
* @author Joa &3*r-9BZ
*/ *LvdrPxU=
publicclass UserManagerImpl implements UserManager { V7+/|P_
ZV07;`I
private UserDAO userDAO; QKoJxjR=^
0bGQO&s
[
/** 26j-1c!NGd
* @param userDAO The userDAO to set. 2[KHmdgtB
*/ 3V]psZS
publicvoid setUserDAO(UserDAO userDAO){ >waA\C}
this.userDAO = userDAO; @*$"6!3s5
} Wx8;+!2Q/
m# ^).+
/* (non-Javadoc) 7re4mrC
* @see com.adt.service.UserManager#listUser MOIVt) ZY
GVdJ&d\x
(org.flyware.util.page.Page) HZ\=NDz
*/ >rFM8P(
public Result listUser(Page page)throws ASNo6dP7
U.|0y =
HibernateException, ObjectNotFoundException { G2J4N2hu
int totalRecords = userDAO.getUserCount(); fl*49-d
if(totalRecords == 0) RLDu5
throw new ObjectNotFoundException Ge76/T%{Q
w/7vXz<
("userNotExist"); BU^E68?G
page = PageUtil.createPage(page, totalRecords); `1R[J4e
List users = userDAO.getUserByPage(page); u 0 K1n_
returnnew Result(page, users); McvLU+
} EFs\zWF
C,{ Ekbg
} qPCI@5n3T?
ITjg]taD
K*"Fpx{M
p vu% p8
PS??wlp7
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 "K*^%{
[wUJ~~2#
询,接下来编写UserDAO的代码: 4WQ
96|F
3. UserDAO 和 UserDAOImpl: 83{v_M
java代码: FFf
~Vmw
c5{3
U[!wu]HMF
/*Created on 2005-7-15*/ 8noo^QO
package com.adt.dao; o(xt%'L`t
?&.Eg^a"
import java.util.List; M,P:<-J
SS-7y:6y>
import org.flyware.util.page.Page; rVnolA*%
DZ5h<1
import net.sf.hibernate.HibernateException; &>hln<a>
~&_BT`a
/** $yMNdBI[
* @author Joa }h\]0'S~J~
*/ zMAlZ[DN
publicinterface UserDAO extends BaseDAO { 2iWxx:e
kn6X
I*
publicList getUserByName(String name)throws -O[9{`i]
Bj\ oo+L/
HibernateException; Hp3T2|uL
; <|m0>X
publicint getUserCount()throws HibernateException; K_BF=C.k
9 N@N U:M+
publicList getUserByPage(Page page)throws {+|Em (M
D-\z'gS
HibernateException; }Ym~[S*x
<:`x> _
} n)>nfnh
-r6LndQs
n0=[N'Tw3
)Ft>X9$
[moz{Y
java代码: BO-=X
78f@
hjY)W;
\-)augq([
/*Created on 2005-7-15*/ bA3pDt).p
package com.adt.dao.impl; 4[m4u6z=
{K+]^M
import java.util.List; uVV;"LVK~
'~kAsn*/
import org.flyware.util.page.Page; Fu#mMn0c
NxQ+z^o\
import net.sf.hibernate.HibernateException; 5y|/}D>
import net.sf.hibernate.Query; {!7 ^w
]abox%U=%
import com.adt.dao.UserDAO; POc-`]6<F
{afR?3GK
/** 0p'=Vel{}
* @author Joa NhA_dskvo
*/ 1t7S:IZ
public class UserDAOImpl extends BaseDAOHibernateImpl Ym"Nj
xk8P4`;d$
implements UserDAO { R} aHo0r
fu?Y'Qet
/* (non-Javadoc) dD0:K3@
* @see com.adt.dao.UserDAO#getUserByName fo30f=^Gi
{(!j6|jK
(java.lang.String) `?R~iLIAq
*/ rN%aP-sa<
publicList getUserByName(String name)throws !FVXNl
m;d#*}n\p
HibernateException { _4jRUsvjY
String querySentence = "FROM user in class 6Q.6
rwUKg[
1N
com.adt.po.User WHERE user.name=:name"; 7-hSso.'
Query query = getSession().createQuery -hIDL'5u-I
~&Gw[Nd1
(querySentence); 7+vyN^XJ"5
query.setParameter("name", name); O0i[GCtP5
return query.list(); F&om^G'U
} ?`%)3gx|
'rwnAr
/* (non-Javadoc) *@2?_b}A
^
* @see com.adt.dao.UserDAO#getUserCount() _n;V iQMu
*/ v&GBu
publicint getUserCount()throws HibernateException { y84=Q
int count = 0; 7TjK;w7xS.
String querySentence = "SELECT count(*) FROM 3,cZ*4('d
"`AIU}[_I
user in class com.adt.po.User"; F(i@Gm=J]
Query query = getSession().createQuery kU5chltGF
;nbUbRb
(querySentence); *VFUC:
count = ((Integer)query.iterate().next /M;A)z
Q!<b"8V]
()).intValue(); =gb.%a{R
return count; ):lq}6J#
} *hp3w
k]=Yi;
/* (non-Javadoc) HV^*_
* @see com.adt.dao.UserDAO#getUserByPage `4'['x
b{KpfbxcI
(org.flyware.util.page.Page) &?=UP4[oif
*/ i(XcNnn6
publicList getUserByPage(Page page)throws )kSE5|:pi
SoY=
HibernateException { Ub8|x]ix
String querySentence = "FROM user in class i-'rS/R
-$#'
com.adt.po.User"; Wv]NFHe#
Query query = getSession().createQuery {%K(O$H#
h-Q3q:
(querySentence); ROr..-[u
query.setFirstResult(page.getBeginIndex()) bojx:g
.setMaxResults(page.getEveryPage()); 0?]*-wvp
return query.list(); =8?gx$r2
} 0^Vc,\P?
fD#VI
} 1)8;9
Ba:
gu[3L
%G& Zm$u=
!YlyUHD
iD)R*vnAi
至此,一个完整的分页程序完成。前台的只需要调用 :bxq%D%|o
H=OKm
userManager.listUser(page)即可得到一个Page对象和结果集对象 Ldnw1xy
T.vkGB=QZ%
的综合体,而传入的参数page对象则可以由前台传入,如果用 \lVxlc0{?
$\xS~w
webwork,甚至可以直接在配置文件中指定。 P%8zxU;
URbu=U
下面给出一个webwork调用示例: 3[: |)i)
java代码: Hf
]aA_:
ssv4#8p3
$okGqu8z.O
/*Created on 2005-6-17*/ !xm87I
package com.adt.action.user; >z*2Og#1
o7N3:)
import java.util.List; v7+f@Z:N*
N'nI
^=
import org.apache.commons.logging.Log; V#:`:-$$+
import org.apache.commons.logging.LogFactory; vDgf}
import org.flyware.util.page.Page; !JtVp&?
tkBp?Wl
import com.adt.bo.Result; >}`q4U6$
import com.adt.service.UserService; zmH 8#
import com.opensymphony.xwork.Action; 2<jbNnj
<QGf9{m
/** tH0=ysf
* @author Joa 3+gp_7L
*/ {O-,JCq/
publicclass ListUser implementsAction{ kK2x';21
Iy\{)+}aS
privatestaticfinal Log logger = LogFactory.getLog @GzEhv
(B@:0}>
(ListUser.class); 4-@D` ,3L
-EV_=a8[y
private UserService userService; LMchNTL
=p 9d4smbn
private Page page; %xE\IRlR
tgn_\ - +
privateList users; =vxiqRm
RkVU^N"
/* 1{B^RR.
* (non-Javadoc) %zx=rn(K
* N>?R,XM
V
* @see com.opensymphony.xwork.Action#execute() |7Z7_YWs
*/ h$)},% e
publicString execute()throwsException{ KD9Y
Result result = userService.listUser(page); -`FPR4;
page = result.getPage(); 6 <JiHVP7
users = result.getContent(); ZSj^\JU
return SUCCESS; HMbF#!E
} F%!ZHE7
5#+G7 'k
/** `RUOZ@r
* @return Returns the page. x{IxS?.j+
*/ #Jt9U1WbF
public Page getPage(){ ,"!t[4p=f
return page; 5tMp@$F\{[
} #Aox$[|@
^<fN
/** *C*n (the
* @return Returns the users. GaMiu!|,
*/ yrO\\No#H
publicList getUsers(){ %dMq'j
return users; :K{!@=o
} 4J3cQ;z
Op^r }7
/** XPnN"Y"y
* @param page ;`IZ&m$
* The page to set. C<Q;3w`#1j
*/ x}I'W?g
publicvoid setPage(Page page){ <
&[=,R0 @
this.page = page; {VqcZhqy/l
} 2aiZ
:=u Ku'~
/** U JO
* @param users FV|/o%XqK
* The users to set. R1Jj 3k
*/ ^W-03
publicvoid setUsers(List users){ m{itMZ@
this.users = users; 5(kRFb'31F
} DuJbWtA
'(M8D5?N-
/** cl s-x@
Kd
* @param userService ~Y^
UP
* The userService to set. NsYeg&>`
*/ W#1t%hT$
publicvoid setUserService(UserService userService){ ][R#Q;y<
this.userService = userService; qI,4uGg
} }lzUl mRTe
} O+U9 p
sG{hUsPa
7U_~_yb
/8 /2#`3R
z Qtg]@S
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, G
@ib
595P04
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 >P*wK9|(
NIn#
么只需要: }$-;P=k
java代码: ?`%7Y~
)LE SdX
=lIG#{`Q
<?xml version="1.0"?> e-vwve
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork 4f+R}Ee7
W|S{v7[l
1.0//EN" "http://www.opensymphony.com/xwork/xwork- Ar@"
K!TS
Ic_>[E?k
1.0.dtd"> "?E>rWz
"0al"?
<xwork> Z>GqLq\`ed
Q)}_S@v|%
<package name="user" extends="webwork- 5e^t;
bnS"@^M
interceptors"> hVPSW# .d
go^?F-
dZ
<!-- The default interceptor stack name 5v:c@n
sBozz #
--> :sD/IM",},
<default-interceptor-ref \%fl`+`
0Q]@T@F.
name="myDefaultWebStack"/> ~4HS
2\
%hcn|-"F
<action name="listUser" =?Y%w%2
Kfho:e,
class="com.adt.action.user.ListUser"> \bJ,8J1C
<param 1p#O(o
e RiP C
name="page.everyPage">10</param> @SH%l]
<result
%W!C
zqqu7.`
name="success">/user/user_list.jsp</result> N;4tvWI
</action> }%z {tn
ROZOX$XM
</package> wBr$3:
_=ani9E]uF
</xwork> |TCHPKN
:{z a[,
*aKT&5Ch-
VFUuG3p)
:CH?,x^!@
gJYB)LjH"
这样就可以通过配置文件和OGNL的共同作用来对page对象设置初值 &_mOw.
EyJWi<
了。并可以通过随意修改配置文件来修改每页需要显示的记录数。 bB01aiUw@l
~";GH20
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 )HPt(Ck
9b
K K
{9(#X]'
#=~n>qn]
W(
O)J$j
我写的一个用于分页的类,用了泛型了,hoho BEn,py7
Q
a(>$. h
java代码: N%8O9Dp8;
&j4 1<A
c rx8+
package com.intokr.util; !JZ)6mtlr
y7)s0g>%H
import java.util.List; (8bo"{zI
ivy+e-)
/** l/|bU9o /u
* 用于分页的类<br> E1p?v!
* 可以用于传递查询的结果也可以用于传送查询的参数<br> 2D,EWk/4
* fTn
* @version 0.01 07L
>@Gf
* @author cheng Qx$CoY
*/ @9yY`\"ed
public class Paginator<E> { 9 F"2$;
privateint count = 0; // 总记录数 &O0@)jIV
privateint p = 1; // 页编号 I)@b#V=
privateint num = 20; // 每页的记录数
{*EA5;
privateList<E> results = null; // 结果 nP9zTa
Ns^[Hb[b'
/** @EPO\\C"f
* 结果总数 P2lDi!q|
*/ H}TzNs
publicint getCount(){
3vs;ZBM
return count; Mp8BilH-T
} -ti
nL(?3
$JH_
publicvoid setCount(int count){ Knd2s~S
this.count = count; f@:.bp8VB8
} lIs<&-0
%<4ZU!2L
/** |$Y0VC4a
* 本结果所在的页码,从1开始 3zV{cm0
* [QC|Kd^#
* @return Returns the pageNo. _FG?zE
*/ hrLPyV:
publicint getP(){ 5.1 c#rL
return p; r-Nv<oH;
} #x)lN
&f2'cR
/** KW17CJ@
* if(p<=0) p=1 e.8(tEqZ1
* X-xN<S q
* @param p eiiI Wr_7
*/ jHP6d =
publicvoid setP(int p){ K'Gv+UC*6
if(p <= 0) 6jdNQC$#B
p = 1; O@$wU9D<
this.p = p; :$=r^LSH
} h5vvizruy
Y|NL #F
/** D7|=ev
* 每页记录数量 ENmfbJ4d~
*/ YIb=rR[ $
publicint getNum(){ Q
db~I#}m'
return num; 1Wz -Z
} o.)8A8
ncF|wz
/** QX1rnVzg0
* if(num<1) num=1 z2EZ0vZ
*/ $i:wS=
w'
publicvoid setNum(int num){ **].d;~[l
if(num < 1) %fv;C
num = 1; `^mPq?f
this.num = num; -#9Hb.Q;
} @W{VT7w
&}YJ"o[I
/** Py&DnG'H
* 获得总页数 'G6M:IXno
*/ dtXAEL\q
publicint getPageNum(){ mX4u#$xs:
return(count - 1) / num + 1; \]@XY_21
} o$S/EZ
`|{6U"n
/** ?1DA
* 获得本页的开始编号,为 (p-1)*num+1 s>pOfXIx
*/ ,3m]jp'
publicint getStart(){ IvW%n(a8^
return(p - 1) * num + 1; s8/sH];
} gM0^k6bB8
_kgGz@/p
/** P|:*OM
p
* @return Returns the results. sHt
PO[h
*/
;8?i
publicList<E> getResults(){ ~v
/N G
return results; K`BNSdEN>
} #_A <C+[
$r>\y (W
public void setResults(List<E> results){ lphELPh
this.results = results; \0{g~cU4
} 2
/rDi
$p(,Qz(.8
public String toString(){ FuA8vTV{
StringBuilder buff = new StringBuilder y([""z3<w
HQpw2bdy
(); $?Et sf#*'
buff.append("{"); c@+ ;4Iz
buff.append("count:").append(count); \Mi] !b|8
buff.append(",p:").append(p); aMUy^>
buff.append(",nump:").append(num); NI@$"
buff.append(",results:").append W7j-siWJ
'1$#onx
(results); iva?3.t
buff.append("}"); 9PU9BYBG
return buff.toString(); 01/?
} |Lq -vs?
FXAP]iqo
} Q%seV<!/
oicj3xkw?
>N&C-6W