Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 X0H!/SlS
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 NAQAU
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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?k>:,'[
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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 ith
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分页支持类: iWB=sL&p
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java代码: (*nT(Adk
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package com.javaeye.common.util; gk[aM~p
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import java.util.List; +N9X/QFKV
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publicclass PaginationSupport { \y)rt )
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publicfinalstaticint PAGESIZE = 30; % X+:o]T
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privateint pageSize = PAGESIZE; '()xHEGl3
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privateList items; E$:*NSXj
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privateint totalCount; ox>^>wR*
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privateint[] indexes = newint[0]; ^aMg/.j
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privateint startIndex = 0; 4 \K7xM!
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public PaginationSupport(List items, int C'+YQ]u
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totalCount){ >CgTs
setPageSize(PAGESIZE); udF~5w
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setTotalCount(totalCount); /-ch`u md
setItems(items); 2LL'J7
setStartIndex(0); w%VU/6~
} tl4V7!U@^z
C:* *;=.
public PaginationSupport(List items, int z8~NZ;A
`* ["UER
totalCount, int startIndex){ |vwVghC
setPageSize(PAGESIZE); axRV:w;E<
setTotalCount(totalCount); ;%5N%0,
setItems(items); _AYK435>N
setStartIndex(startIndex); :P\7iW
} 69?wc!
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public PaginationSupport(List items, int %@ODs6 R0
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totalCount, int pageSize, int startIndex){ !/*\}\'4
setPageSize(pageSize); yZ(zdM\/sL
setTotalCount(totalCount); p8H'{f\G
setItems(items); GR.^glG?6
setStartIndex(startIndex); e&F8m%t
} v
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publicList getItems(){ vq0Tk
bzs
return items; qIE9$7*X
} }J`w4P
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publicvoid setItems(List items){ K?Nhi^f"L
this.items = items; k&q;JyUi
} ufZDF=$7
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publicint getPageSize(){ D~fl JR
return pageSize; f:,DWw`B
} 8f4b&ah
sA/D]W.P
publicvoid setPageSize(int pageSize){ vHc%z$-d
this.pageSize = pageSize; #PW9:_BE
} Uh4%}-;
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publicint getTotalCount(){ G1tY) _-8[
return totalCount; z}9(x.I
} I)6+6pm
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publicvoid setTotalCount(int totalCount){ NC`aP0S
if(totalCount > 0){ o]_dJB
this.totalCount = totalCount; vjCu4+w($Z
int count = totalCount / aQc leTb
$am$EU?s
pageSize; Xp% v.M
if(totalCount % pageSize > 0) wqs?828x
count++; Hqx-~hQO
indexes = newint[count]; mzKiO_g}
for(int i = 0; i < count; i++){ hJ? O],4J
indexes = pageSize * I@~QV@U
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i; J#(LlCs?@c
} D&
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}else{ }W8;=$jr
this.totalCount = 0; 9uO 2Mm
} IGQFtO/x
} RnE4<Cy
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publicint[] getIndexes(){ gp?uHKsM
return indexes; 6]N;r5n
} /NFj(+&g+
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publicvoid setIndexes(int[] indexes){ 1{.|+S Z!
this.indexes = indexes; 70nqD>M4
} L,`LN>
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publicint getStartIndex(){ T!kN)#S
return startIndex; q`a'gJx#y
} 1#2 I
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publicvoid setStartIndex(int startIndex){ @ioJ]$o7
if(totalCount <= 0) E_wCN&`[
this.startIndex = 0; 6l1jMm|=
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elseif(startIndex >= totalCount) g2ixx+`?|:
this.startIndex = indexes lU\[aNs
]^7@}Ce_
[indexes.length - 1]; ]7BvvQ
elseif(startIndex < 0) 5d^sA;c
this.startIndex = 0; 5m 4P\y^a
else{ =R|HV;9 h
this.startIndex = indexes ]|ag
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[startIndex / pageSize]; i)#dWFDTv
} P>D)7V9Hh
} mdDOvm:&
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publicint getNextIndex(){ KYI/
int nextIndex = getStartIndex() + U_Ptqqt%
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pageSize; %OCb:s
if(nextIndex >= totalCount) j2[+ztG
return getStartIndex(); tw/dD +
else 9:|{6_Y
return nextIndex; #q$HQ&k
} ()?(I?II
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publicint getPreviousIndex(){ v{N`.~,^
int previousIndex = getStartIndex() - pE0Sw}A:9
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pageSize; F~W6Bp^W
if(previousIndex < 0) [l??A3G
return0; ?e4YGOe.
else -@2iaQ(5a2
return previousIndex;
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} k]|~>9eY]
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} lfgq=8d
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抽象业务类 l|[N42+
java代码: *:7rdzn
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/** ^uc=f2=>,
* Created on 2005-7-12 G e@{_
*/ iWkWR"ysy
package com.javaeye.common.business; h,N?Ab'S
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import java.io.Serializable; EME|k{W
import java.util.List; ;JT-kw6l5K
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import org.hibernate.Criteria; Ll't>)
import org.hibernate.HibernateException; qInR1 r<
import org.hibernate.Session; t{9GVLZ
import org.hibernate.criterion.DetachedCriteria; \V63qg[
import org.hibernate.criterion.Projections; g:@#@1rB6
import oZgjQM$YP
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org.springframework.orm.hibernate3.HibernateCallback; ^{`exCwMx
import q.bSIV|
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org.springframework.orm.hibernate3.support.HibernateDaoS :3Ox~o
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upport; M|h3Wt~7
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import com.javaeye.common.util.PaginationSupport; TIDO@NwF
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public abstract class AbstractManager extends
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HibernateDaoSupport { U7F!Z(
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privateboolean cacheQueries = false; JH9J5%sp
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privateString queryCacheRegion; vvMT}-!
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publicvoid setCacheQueries(boolean r l%
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cacheQueries){ LEdh!</'24
this.cacheQueries = cacheQueries; $s:aW^k
} #c!lS<z
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publicvoid setQueryCacheRegion(String C&%_a~
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queryCacheRegion){ "KpGlY?^
this.queryCacheRegion = H7n>Vx:L-
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queryCacheRegion; C1)!f j=
} k y7Gwc
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publicvoid save(finalObject entity){ Ti5-6%~&
getHibernateTemplate().save(entity); r,p%U!S<hV
} ZY+qA
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publicvoid persist(finalObject entity){ oMa6(3T?E
getHibernateTemplate().save(entity); XRi8Gpg
} m:2^=l4
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publicvoid update(finalObject entity){ CD~.z7,LC
getHibernateTemplate().update(entity); Xx:"4l.w.
} L="}ErmK
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publicvoid delete(finalObject entity){ U5de@Y
getHibernateTemplate().delete(entity); DvvK^+-~
} gM:".Ee
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publicObject load(finalClass entity, wIt}dc
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finalSerializable id){ Dp9+HA9t
return getHibernateTemplate().load (!WD1w
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(entity, id); :vbW
} O\r0bUPE
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publicObject get(finalClass entity, kxv1Hn"`{E
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finalSerializable id){ hwv/AnX~O
return getHibernateTemplate().get \4fQMG
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(entity, id); 'H;*W |:-]
} (GfZ*
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publicList findAll(finalClass entity){ JWxwJex
return getHibernateTemplate().find("from gPPkT"
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" + entity.getName()); @q)d
} P&Vv/D
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publicList findByNamedQuery(finalString wibNQ`4k
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namedQuery){ s~X%Y<9l
return getHibernateTemplate =I_'.b
cr;da)
().findByNamedQuery(namedQuery); tCt#%7J;a
} eaU
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publicList findByNamedQuery(finalString query, ?:0Jav
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finalObject parameter){ BI@[\aRLQ
return getHibernateTemplate S_H+WfIHV'
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().findByNamedQuery(query, parameter); 8}:nGK|kx
} h<QY5=SF
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publicList findByNamedQuery(finalString query, ]`WJOx4
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finalObject[] parameters){ Nh+ H 9
return getHibernateTemplate 5z)~\;[ -
} Q+|W=2t
().findByNamedQuery(query, parameters); N;%6:I./
} F#E3q|Q"BS
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publicList find(finalString query){ JucY[`|JV
return getHibernateTemplate().find y@yD5$/
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(query); <#4h}_xA%
} HZZn'u
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publicList find(finalString query, finalObject $*m-R*kt
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parameter){ Tid a a
return getHibernateTemplate().find \i&<s;
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(query, parameter); 'J|_2*
} MolgwVd
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public PaginationSupport findPageByCriteria 5"H=zJ=r
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(final DetachedCriteria detachedCriteria){ fc>L K7M
return findPageByCriteria M',?u
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); 2Tppcj v
} [2cD:JL
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public PaginationSupport findPageByCriteria j] [,J49L
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(final DetachedCriteria detachedCriteria, finalint c&Q$L }
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startIndex){ ?aMOZn?
return findPageByCriteria d/@,@8:
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(detachedCriteria, PaginationSupport.PAGESIZE, <#HYqR',
}<:}XlwT%
startIndex); /qw.p#
} QS`]
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public PaginationSupport findPageByCriteria C7AUsYM
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(final DetachedCriteria detachedCriteria, finalint 9N3eN
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pageSize, kcxAd
finalint startIndex){ x,V r=FB
return(PaginationSupport) )`D:F>p*
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getHibernateTemplate().execute(new HibernateCallback(){ SgOheN-
publicObject doInHibernate *8XEYZa
@KAI4LP
(Session session)throws HibernateException { #.[k=dj
Criteria criteria = 3;Fhg!ZO
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detachedCriteria.getExecutableCriteria(session); 9nbLg5P
int totalCount = TS5Q1+hWHV
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((Integer) criteria.setProjection(Projections.rowCount &+R?_Ooibk
ehY5!D1Q
()).uniqueResult()).intValue(); Rlirs-WQ
criteria.setProjection :Ux_qB
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(null); Z%\,w(o[h
List items = I<tm"?q0
8\gjST*
criteria.setFirstResult(startIndex).setMaxResults )dSi/
xN%K^Tree
(pageSize).list(); ;bhT@aB1
PaginationSupport ps = uW3!Yg@
po7q mLq
new PaginationSupport(items, totalCount, pageSize, v*yuE5{
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startIndex); 7VI*N)OZ8
return ps; @\I#^X5lv
} Rws3V"{`[
}, true); f y8Uk;
} *uvQ\.
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public List findAllByCriteria(final FC"8#*x
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DetachedCriteria detachedCriteria){ 7t_^8I%[
return(List) getHibernateTemplate 8HdAFRw
^sg,\zD 'X
().execute(new HibernateCallback(){ sn>~O4"
publicObject doInHibernate Ecx<OTo
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(Session session)throws HibernateException { ^zgo#J5O
Criteria criteria = /H+a0`/
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detachedCriteria.getExecutableCriteria(session); M&
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return criteria.list(); \5cpFj5%
} n{SJ_S#a.a
}, true); A.w:h;7
} Dn }Jxu'(
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public int getCountByCriteria(final !5?<% *
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DetachedCriteria detachedCriteria){ da~],MN
Integer count = (Integer) tFl"n;~T
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getHibernateTemplate().execute(new HibernateCallback(){ P
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publicObject doInHibernate 1g~R/*Jo
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(Session session)throws HibernateException { /|#fejPh
Criteria criteria = t );/'3|
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detachedCriteria.getExecutableCriteria(session); v74&BL]a
return 0Fr?^3h
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criteria.setProjection(Projections.rowCount *k>n<p3dd
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()).uniqueResult(); <_KIK
} -n5)w*b,
}, true); VOh4#%Vj
return count.intValue(); @$K"o7+]
} F1Bq$*'N$w
} _t}WsEQ+P
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用户在web层构造查询条件detachedCriteria,和可选的 E q+_&Wk
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 7 x?<*T
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PaginationSupport的实例ps。 U|j`e5)
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ps.getItems()得到已分页好的结果集 5.J.RE"M
ps.getIndexes()得到分页索引的数组 ]:/Q]n^
ps.getTotalCount()得到总结果数 mUx+Y ]Ep
ps.getStartIndex()当前分页索引 63x?MY6
ps.getNextIndex()下一页索引 t5IEQ2
ps.getPreviousIndex()上一页索引 iMRwp+$
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 57'4ljvYi
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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 DkAAV9*
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一下代码重构了。 I[X772K
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我把原本我的做法也提供出来供大家讨论吧: B@
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首先,为了实现分页查询,我封装了一个Page类: P J[`|
java代码: 'a.qu9PJ
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/*Created on 2005-4-14*/ ~2khgZ
package org.flyware.util.page; I4?5K@a
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/** 07=mj%yV
* @author Joa t}/( b/VD
* x`)&J
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*/ [Cv/{f3]u{
publicclass Page { I?G: p+
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/** imply if the page has previous page */ 5bpEYW+
privateboolean hasPrePage; W-lN>]5}m
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/** imply if the page has next page */ }txX;"/
privateboolean hasNextPage; Aj]V`B:65
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/** the number of every page */ R@k&SlL'`
privateint everyPage; "kgdbAZ
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/** the total page number */ /%A*aGyIc
privateint totalPage; ZbAcO/
[Hh9a;.*}h
/** the number of current page */ x0:m-C
privateint currentPage; a-L;*
*,WU?tl&
/** the begin index of the records by the current /FEVmH?
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query */ !f&g-V
privateint beginIndex; @/-\k*T
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/** The default constructor */ t |A-9^t'!
public Page(){ (0y~%J
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} m5Di=8
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/** construct the page by everyPage 3"KCh\\b
* @param everyPage >[=^_8M
* */ 9j:"J` '
public Page(int everyPage){ C#Iybg
this.everyPage = everyPage; )gy!GK
} QbpFE)TYJ|
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#
/** The whole constructor */ 55c|O
public Page(boolean hasPrePage, boolean hasNextPage, r#]WI|
$,Yd>%Y
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int everyPage, int totalPage, pgZXJ
int currentPage, int beginIndex){ Sa;qW3dt3E
this.hasPrePage = hasPrePage; tS8u
this.hasNextPage = hasNextPage; ?o#%Xs
this.everyPage = everyPage; ?zHPJLv|Y
this.totalPage = totalPage; L<{i,'M
this.currentPage = currentPage; )iK6:s#
this.beginIndex = beginIndex; pOG1jI5<{8
} 2'MZ s]??w
Ffta](Z;
/** ,>+p-M8ZL
* @return WKa~[j|-K
* Returns the beginIndex. R/>@+
*/ PxkOT*
publicint getBeginIndex(){ PQ$%H>{
return beginIndex; ;)^`3`
} N7
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/** t"'7m^j
* @param beginIndex LsS
* The beginIndex to set. XaPV94
*/ >y:,9;
publicvoid setBeginIndex(int beginIndex){ 7!TueP0Zd
this.beginIndex = beginIndex; VrQmP
} 'K{Z{[s{
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/** x-.?HS[
* @return +@k+2?]
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* Returns the currentPage. eu|;eP-+d
*/ 6wECo
publicint getCurrentPage(){ !.(P~j][
return currentPage; T&o(N3lW
} G.d TvLv
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/** yx&51G$
* @param currentPage ;8{4!S&b
* The currentPage to set. C-6F]2:
*/ ktBj|-'>
publicvoid setCurrentPage(int currentPage){ !sW(wAy?o
this.currentPage = currentPage; l &5QZI0I
} 1--C~IjJ+
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/** y^v6AM
* @return 90*5
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* Returns the everyPage. YU5(g^<
*/ J!pygn O
publicint getEveryPage(){ rb+j*5Es
return everyPage; ]B3=lc"
} Vi]W |bP
kbMWGB%;
/** OO*zhGD;[
* @param everyPage d,Yw5$i
* The everyPage to set. P&ptJtNg
*/ RM]M@%,K
publicvoid setEveryPage(int everyPage){ B
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this.everyPage = everyPage; .|b$NM
} K<ft2anY5
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/**
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* @return 27O|).yKX
* Returns the hasNextPage. @H7d_S
*/ _zn.K&I-*k
publicboolean getHasNextPage(){ *<jAiB,O*
return hasNextPage; Q1
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} p=GBUII #
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/** N&g3t%F
* @param hasNextPage b
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* The hasNextPage to set. 4;]hK!AXS
*/ mA+&Io
publicvoid setHasNextPage(boolean hasNextPage){ mmEYup(l0;
this.hasNextPage = hasNextPage; O%!!w
} a>]uU*Xm
vMt/u?oB
/** <[\`qX
* @return v|%Z+w
* Returns the hasPrePage. '~[d=fwH
*/ e2t-4}
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publicboolean getHasPrePage(){ QaS7z#/?.
return hasPrePage; h
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} s!c`=
9c#+qH
/** pU%n]]qF
* @param hasPrePage #W'HR
* The hasPrePage to set. >
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*/ wq(7|!Eix
publicvoid setHasPrePage(boolean hasPrePage){ nvJf/90$
this.hasPrePage = hasPrePage; ]?+p5;{y4
} !K}~/9Z=m
Yu[ t\/
/** f~y%%+{p
* @return Returns the totalPage. >x+6{^}Q >
* o` ZQ d,3
*/ Avd
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publicint getTotalPage(){ )d1_Wm#B
return totalPage; ,PuL{%PXu
} r1.nTO%
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/** ICs\
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* @param totalPage %g$V\zmU
* The totalPage to set. WEQ1 Seq
*/ +HeTtFo{M
publicvoid setTotalPage(int totalPage){ /F-qP.<D,r
this.totalPage = totalPage; ;":zkb{
} */|lJm'R
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} =;3Sx::=
7/ysVWt
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];a=Pn-:}G
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 l@ H
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个PageUtil,负责对Page对象进行构造: EB=-H#
java代码: ^xHTW g%9
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/*Created on 2005-4-14*/ hMUs"
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package org.flyware.util.page; GCX G/k?w:
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import org.apache.commons.logging.Log; d`nVc50
import org.apache.commons.logging.LogFactory; XZJ+h,f
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/** Q6AC(n@:FV
* @author Joa
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* feNdMR7eM
*/ zj`v?#ET
publicclass PageUtil { pUq1|)g
[*H N"
privatestaticfinal Log logger = LogFactory.getLog 4.h=&jz&
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(PageUtil.class);
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/** }YMy6eW4
* Use the origin page to create a new page t!x5 fNo)
* @param page y[\VUzD*'
* @param totalRecords m&\h4$[kql
* @return l>{R`BZ/
*/
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publicstatic Page createPage(Page page, int U,gti,IX^
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totalRecords){ %D8ZO0J7H
return createPage(page.getEveryPage(), 7L@K _ZJ
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page.getCurrentPage(), totalRecords); 7J|VD#DE$Y
} 0-|byAh
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/** ;3: q?&
* the basic page utils not including exception !{)tSipd
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handler M57T2]8,
* @param everyPage w{uuSe
* @param currentPage T2 Y,U {
* @param totalRecords mG`e3X6@-
* @return page T[4<R 5}
*/ )h|gwERj
publicstatic Page createPage(int everyPage, int {]_r W/
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currentPage, int totalRecords){ X
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everyPage = getEveryPage(everyPage); ;D
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currentPage = getCurrentPage(currentPage); x{,q]u /
int beginIndex = getBeginIndex(everyPage, m-DsY
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currentPage); <Ib[82PU
int totalPage = getTotalPage(everyPage, ?(m
jx
vR=6pl$|~~
totalRecords); J9Ou+6 u(
boolean hasNextPage = hasNextPage(currentPage, 9,_mS{+B
] GTAq
totalPage); $:j G- r
boolean hasPrePage = hasPrePage(currentPage); E V^~eTz
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returnnew Page(hasPrePage, hasNextPage, .E&z$N
everyPage, totalPage, @qjfZH@
currentPage, ;9ly'<up
nJ"YIT1K]p
beginIndex); ]%Nlv(
} H_Kj7(=&>
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privatestaticint getEveryPage(int everyPage){ hL;8pE8
return everyPage == 0 ? 10 : everyPage; !F4@KAv
} 6"t;gSt4
L%$|^T=%
privatestaticint getCurrentPage(int currentPage){ E+ tB&
return currentPage == 0 ? 1 : currentPage; N,
*m ,
} D?,#aB"
M$d%p6Cv
privatestaticint getBeginIndex(int everyPage, int G4;3cT3'
P<2+L|X?}
currentPage){ |vMpXiMxxT
return(currentPage - 1) * everyPage; saAxGG
} gEhN3(
@]c(V%x
privatestaticint getTotalPage(int everyPage, int hj$e|arB
8kOKwEX
totalRecords){ N0w`!<y:c
int totalPage = 0; HCJ>X;(`f?
f%)zg(YlO
if(totalRecords % everyPage == 0) o|iYd
n\
totalPage = totalRecords / everyPage; c8M2 ^{O,`
else aJe^Tp(
totalPage = totalRecords / everyPage + 1 ; ^eGNgE
iy\nio`
return totalPage; st&
} 2Nm>5l
kctzNGF|
privatestaticboolean hasPrePage(int currentPage){ ^(f4*m6`
return currentPage == 1 ? false : true; L0]_hxE?
} @a>2c$%
s/e"'Hz
privatestaticboolean hasNextPage(int currentPage, 6PF8
/@Nh
Z,;cCxE
int totalPage){ ?$Wn!"EC8
return currentPage == totalPage || totalPage == 5,;`$'?a%
G"59cv8z4R
0 ? false : true; KkMay
} u=NSsTP&
j9U%7u]-k
q$.{j"cZV
} dg7=X{=9jv
KZe)K_1[
tYqs~B3
I.@hW>k
A[dvEb;r
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。 X$b={]b
OR Wm
C!
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 &G >(9
[;oCYb$9
做法如下: ,chf~-d
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 Grz 3{U
0 Hw-59MK
的信息,和一个结果集List: xf>z @)e
java代码: |nk3^;Yf
l\!-2 T6Y
]G}B 0u3
/*Created on 2005-6-13*/ 's!-80sd
package com.adt.bo; ~;OYtz
25|8nfeC5
import java.util.List; s;YKeE!8
W"xP(7X
import org.flyware.util.page.Page; NOK/<_/
HFQR
;9]
/** nCvPB/-
* @author Joa ] 43bere
*/ (5Tvsw`
publicclass Result { }^K/?dM
}T0K^Oe+eS
private Page page; 1fL<&G
tAFti+Qb
private List content; &~f3 psA
FM5e+$>@
/** Uo_tUp_Q
* The default constructor ]Lqt(c
*/ p'?w2YN/
public Result(){ oXt,e
super(); hsG#6?l3
} rt +..t\
do>"[RO
/** ?68uS;
* The constructor using fields :Ze+%d=
* +>g`m)?p
* @param page =KX<_;E
* @param content nxap\Lf
*/ $
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public Result(Page page, List content){ agOk*wH5
this.page = page; i!dv0|_
this.content = content; \H5Jk$*
} *sfD#Bi]
N<_Ko+VF
/** bT!($?GNdg
* @return Returns the content. snp v z1iS
*/ d2ENm%q*PX
publicList getContent(){ [{<dbW\ 9
return content; VLg
EX4
} *Wb=WM-.
)yb+M ez
/** SHqyvF
* @return Returns the page. 6=PiVwI
*/ x@cN3O
public Page getPage(){ K,}w]b
return page; ~%|G+m>
} xQlT%X;'
H.J5i~s
/** ?&h3P8
* @param content mg+k'Myo+
* The content to set. ~HUZ#rUHm>
*/ 9 K
public void setContent(List content){ )3muPMaY
this.content = content; +ydm,aKk
} WA.\*Nqz e
kJ: 2;t=
/** ZAg;q#z j
* @param page 26:evid
* The page to set. 5>ST"l_ca
*/ O'}llo
publicvoid setPage(Page page){ ?9u4a_x
this.page = page; N^elVu4 K
} ^4`&EF
} _&
4its
h<[+HsI
`:-J+<`
abY0)t
~' =lou
2. 编写业务逻辑接口,并实现它(UserManager, voRfjsS~
<qiICb)~
UserManagerImpl) DB&SOe
java代码: hD 46@
! VRI_c
z-0:m|=yH
/*Created on 2005-7-15*/ H$-$2?5
package com.adt.service; u5gZxO1J5
2A$0CUMb
import net.sf.hibernate.HibernateException; ~2N-k1'-'
"L~@.W!@
import org.flyware.util.page.Page; ^[M~K5Y
hrM"Zg
import com.adt.bo.Result; 5(}H
?
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/** =
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* @author Joa D$_8rHc\A
*/ &R\XUxI
publicinterface UserManager { "zZ&n3=@
dV$!JTsd
public Result listUser(Page page)throws x9`ZO<L$
2uo8j F.h
HibernateException; YbvX$/zGu
5|WOBOh>`&
} owMuT^x?
/;UTC)cJ
P6OM)>C
<J# R3{
\FI^Vk
java代码: ^~I @
spR4
X"J%R/f
iE{Oit^aG
/*Created on 2005-7-15*/ >7FSH"8[,
package com.adt.service.impl; "X?LAo
DM/hcY$MW
import java.util.List; Nzc>)2% N
OX,F09.C
import net.sf.hibernate.HibernateException;
,(hY%M&\
anitqy#E
import org.flyware.util.page.Page; =w ,(M
import org.flyware.util.page.PageUtil; xDe47&qKM
g Np-f
import com.adt.bo.Result; vj@V
!j?
import com.adt.dao.UserDAO; k*9%8yi_ U
import com.adt.exception.ObjectNotFoundException; ;G$)MS'nB
import com.adt.service.UserManager; = P8~n2V
9_`3IJ
/** :,=Fx</H
* @author Joa '!j(u@&!
*/ >?Qxpqf2
publicclass UserManagerImpl implements UserManager { =[8d@d\
QW:Z[?39^
private UserDAO userDAO; 0JOju$Bl,
i-Ljff
/** r?XDvU
* @param userDAO The userDAO to set. C_89YFn+
*/ a j_:|]j
publicvoid setUserDAO(UserDAO userDAO){ R mgxf/
this.userDAO = userDAO; 1#kawU6[]
} %[+/>e/m
S&`O\!NF
/* (non-Javadoc) o9^$hDs,si
* @see com.adt.service.UserManager#listUser 4jD\]Q="1
%1@.7uTN
(org.flyware.util.page.Page) 0<"tl0p_
*/ :=B[yD!
public Result listUser(Page page)throws nR#a)et
a#6,#Q"
HibernateException, ObjectNotFoundException { A9.;>8!u
int totalRecords = userDAO.getUserCount(); 92NC]_jw
if(totalRecords == 0) \Qb>:
throw new ObjectNotFoundException s2%0#6c'c
Dl@{}9
("userNotExist"); %L.rcbg:<c
page = PageUtil.createPage(page, totalRecords); zZw@c?
List users = userDAO.getUserByPage(page); d<)s@Ntgm
returnnew Result(page, users); TyyRj4>
} f@#w{W,3
l+'`BBh*]
} AzW%+ LUD
dnLo(<{<U
N+[}Gb"8q
)<tzm'Rc
jBGG2[hV
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 *%]+sU
iu+zw[f
询,接下来编写UserDAO的代码: xQ_:]\EZ
3. UserDAO 和 UserDAOImpl: S@;&U1@h
java代码: GZ}*r{
vJzx Py|
G-Zr M
/*Created on 2005-7-15*/ V=Ww>
package com.adt.dao; sd]0Hx[
>J?jr&i
import java.util.List; sL;z"N@PK
SIJ# ?0,
import org.flyware.util.page.Page; V&$ J;
t
PAt?
import net.sf.hibernate.HibernateException; o7hH9iY
p}cd}@cQ6
/** kz3?j<
* @author Joa s-Q7uohK
*/ cG<Q`(5~
publicinterface UserDAO extends BaseDAO { H{&a)!Ms
m.|qVN
publicList getUserByName(String name)throws #.RG1-L
v_[)FN"]Y.
HibernateException; F?!};~$=Z
I>(;bNgNE
publicint getUserCount()throws HibernateException; DHSU?o#jY
KLj 4LOs
publicList getUserByPage(Page page)throws 0:PH[\Z
Uv#>d}P
HibernateException; B=r]_&u-u
3m?@7 F
} ID_|H?.
uVoF<={
i,C0o
?nj"Ptzs
%D`^
java代码: _m)gO/02A
\fkS_r, i
:9v*,*@x
/*Created on 2005-7-15*/ )ylv(qgV
package com.adt.dao.impl; \a9D[wk;@
OcyiL)tv 5
import java.util.List; cWX"e6
1D3dYVE
import org.flyware.util.page.Page; .eZPp~[lAN
tRpL0 =y
import net.sf.hibernate.HibernateException; KY;uO 8Te
import net.sf.hibernate.Query; ,'/HcF?yf
v3=&{}+j.
import com.adt.dao.UserDAO; Y#Sd2h,^X
QYODmeu
/** #3 }5cC8_
* @author Joa ir( -$*J
*/ S&;T_^|
public class UserDAOImpl extends BaseDAOHibernateImpl 8YT_DM5iI
.x\/XlM
implements UserDAO { P 'FPe55F
Q6e'0EIKC
/* (non-Javadoc) (25^r
* @see com.adt.dao.UserDAO#getUserByName ,E
n(gm
ZQgxrZx3
(java.lang.String) tk]_QX
%
*/ Lqz}&A
publicList getUserByName(String name)throws qcpG}o+&D
}R?v"6aBS
HibernateException { lN*1zM<6;
String querySentence = "FROM user in class \(3Qqbw
P22y5z~
com.adt.po.User WHERE user.name=:name"; DKaG?Y,*p
Query query = getSession().createQuery )U"D4j*p
>Rz#g*@E
(querySentence); 6qmo
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query.setParameter("name", name); 4F1.D9u
return query.list(); ePPp)=
} 2\$WP-)%
P^uP$D
/* (non-Javadoc) )edU <1P
* @see com.adt.dao.UserDAO#getUserCount() 945
|MQPn
*/ 8as$h*Wh
publicint getUserCount()throws HibernateException { d=.n|rS4
W
int count = 0; jN5} 2 p*
String querySentence = "SELECT count(*) FROM ;c \zgs~"T
3f7t%
user in class com.adt.po.User"; +lk\oj$S+
Query query = getSession().createQuery H *z0xxa
KNUMz4
(querySentence); l{D,O?`Av
count = ((Integer)query.iterate().next G*{ u(x(
f"Vm'0r
()).intValue(); b@Mng6R
return count; zd*W5~xKg
} nJM9c[Ou^H
f6aT[Nw<
/* (non-Javadoc) 56j/w[&8
* @see com.adt.dao.UserDAO#getUserByPage OJC*|kN-#^
E-7a`S
(org.flyware.util.page.Page) y[ rB"
*/ @poMK:
publicList getUserByPage(Page page)throws $.x?in|_
PL$(/Z
HibernateException { !m/Dd0
String querySentence = "FROM user in class v2W"+QS}u
2)j#O
com.adt.po.User"; ^r?sgJ
Query query = getSession().createQuery ]Pg?(lr6)
:n%sU*'T
(querySentence); ,co9f.(w
query.setFirstResult(page.getBeginIndex()) V]CK'
.setMaxResults(page.getEveryPage()); VE S4x%r=
return query.list(); D/%b@Ls2ze
} IZ(CRKCGBl
07G*M ]
} >sl1 cC
dBD4ogo1
\qK}(xq[
ovBd%wJ 0
zdpLAr
至此,一个完整的分页程序完成。前台的只需要调用 {bq-: CZe
N6m*xxI{
userManager.listUser(page)即可得到一个Page对象和结果集对象 (
_F
d8y=.
的综合体,而传入的参数page对象则可以由前台传入,如果用 +ouy]b0`t
I!i#=
webwork,甚至可以直接在配置文件中指定。 `sp'Cl!
,h)T(
下面给出一个webwork调用示例: l4B O@
java代码: 5fDtSsW
S|5lx7
HDae_.
/*Created on 2005-6-17*/ .WPR}v,.Z
package com.adt.action.user; ]&tr\-3
kl{OO%jZ
import java.util.List; vS,G<V3B
v%PWr5]
import org.apache.commons.logging.Log; ^zluO
import org.apache.commons.logging.LogFactory; fKK-c9F
import org.flyware.util.page.Page; Xe^=(| M
A%2M]];%X
import com.adt.bo.Result; !6fpMo
import com.adt.service.UserService; =D"63fP1
import com.opensymphony.xwork.Action; &.bR1wX
*U^\Mwp
/** "GC]E8&>H
* @author Joa u g$\&rM>
*/ Z=5}17kA
publicclass ListUser implementsAction{ YPJx/@Z`
uP'w.nA&2
privatestaticfinal Log logger = LogFactory.getLog hZ /
`F`'b)
(ListUser.class); Vh[o[ U
y2hFUq
private UserService userService; lIc9,|FL
p(&o'{fb
private Page page; ]TZWFL-
u:u 7|\q
privateList users; M[3w EX^
D"XQ!1B%
/* ?%fZvpn -
* (non-Javadoc) ~^5n$jq
* 9QQ@Y}
* @see com.opensymphony.xwork.Action#execute() CR PE?CRQF
*/ :W<,iqSCm
publicString execute()throwsException{ WHj4#v(
Result result = userService.listUser(page); C-b% PgA
page = result.getPage(); $j2)_(<A%Q
users = result.getContent(); +mW$D@Pf
return SUCCESS; [^BUhm3a
} N~<}\0
la{:RlW
/** oZcwbo8
* @return Returns the page. d`][1rZk
*/ &Or=_5Y`
public Page getPage(){ )tQ6rd'
return page; U.sPFt
} T9v#Jb6
fy-Z{
/** `}Zbfe~
* @return Returns the users. X^ ]$/rI)
*/ <hC3#dNRd
publicList getUsers(){ 8PVs!?Nne
return users; W>s9Mp
} U;dt-3?=.h
[?6D1b[
/** yzzre>F
* @param page 6uE1&-:L
* The page to set. ;Sl0kSu
*/ 6e-h;ylS
publicvoid setPage(Page page){ '#
2J?f'
this.page = page; 4J2F>m40
} GoA>sK
T@.m^|~
/** naCI55Wx
* @param users z"C(#Y56 x
* The users to set. ij5=f0^4.
*/ v7u}nx
publicvoid setUsers(List users){ hg/&[/eodm
this.users = users; mqc Z3lsv
} 3Ty{8oUs^
-#M~NbI,
/** l'8TA~
* @param userService "/h"Xg>q
* The userService to set. NJ!#0[@C
*/ Dk6\p~q
publicvoid setUserService(UserService userService){ /1
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this.userService = userService; -2Cf)>`v
} n|2-bRK-
} K T72D
5kZ yiC*
6Tmb@<I_
^`5Yxpz
`l#$l3v+
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, QHz76i!=>
p<['FRf"
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 !+ hgKZ]
vXZz=E
AH
么只需要: t[ocp;Q
java代码: T mE4p
!h(0b*FUJ
3YF]o9
<?xml version="1.0"?> ~?+m=\
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork ~i#xjD5
l:/V%{sx
1.0//EN" "http://www.opensymphony.com/xwork/xwork- )% c)-c
=qQQ^`^F'~
1.0.dtd"> 9@+X?Nhv5
{oeQK
<xwork> Nn\\}R
u`nn{C4D"
<package name="user" extends="webwork- Zul32]1r
l@jJJ)Qyk
interceptors"> <xNM@!'\h
Ot<!Y M
<!-- The default interceptor stack name LA0x6E+I
@= 9y5r
--> f#MN-1[67
<default-interceptor-ref EmoU7iy
$^ 3 f}IzA
name="myDefaultWebStack"/> v> PHn69PU
e-t`\5b;
<action name="listUser" :|Ty 0>k
W5g!`f
class="com.adt.action.user.ListUser"> +:Zi(SuS]
<param X;RI7{fW%X
mmK_xu~f28
name="page.everyPage">10</param> U<gw<[>f
<result Ro$XbU)
~`fB\7M
name="success">/user/user_list.jsp</result> h:90K
</action> :AGQkJb
Im#$iPIvT
</package> 4 l(o{{
*r3vTgo$
</xwork> y~ LVK8
y>PbYjuIU
go5!zSs
Jz b".A
>f/g:[
t$|6}BX
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 C[,-1e?
?J-KB3Uv3
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。 C" WZsF^3
(#`o>G(
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 [i _x
1
{`55nwd
(7
iMIY
s:H1v&t,<
I78pul8!
我写的一个用于分页的类,用了泛型了,hoho \[jItg,+
Dh<e9s:
java代码: T]`"
Xl8
_=#mmZkq
58,mu#yq6
package com.intokr.util; ;zODp+4@Q
OwUbm0)h^V
import java.util.List; EG6fC4rfC
IgJC>;]u
/** %4J?xhd
* 用于分页的类<br> UPF=X)!M
* 可以用于传递查询的结果也可以用于传送查询的参数<br> O:)@J b2
* _aYQ(FO
* @version 0.01 2ra4t]f6
* @author cheng hI0l2OE
*/ `Fr$q1qae{
public class Paginator<E> { i=@*F$,
privateint count = 0; // 总记录数 zZ-*/THB@R
privateint p = 1; // 页编号 n9 DFa3
privateint num = 20; // 每页的记录数 Tr)[q>
privateList<E> results = null; // 结果 RqR X
{wySH[V
/** f5Oh#
* 结果总数 ,fRb6s-
*/ gw:BKR'o
publicint getCount(){ u)-l+U.
return count; l"CONzm!
} |Sm/Uq(c
;p8xL)mUP
publicvoid setCount(int count){ .rHO7c,P~
this.count = count; x`&W[AA4
} }$jIvb,3?
`^ok5w"oi
/** aL}_j#m{
* 本结果所在的页码,从1开始 v3Kqs:"\
* AsOI`@FV
* @return Returns the pageNo. ~7g6o^A>
*/ SrIynO
publicint getP(){ F44")fY
return p; #q%/~-Uk
} zF7T5Ge
b._pG(o1
/** e6Y0G,K
* if(p<=0) p=1 ]h6<o*
* tEl_A"^e
* @param p }<p%PyM
*/ {1[8,Ho
publicvoid setP(int p){ %Ok.XBS)
if(p <= 0) vHmn)d1pl
p = 1; b.(^CYYQ
this.p = p; 7JbrIdDl|
} =zdRoXBY[b
u}$3.]-.?T
/** kmwFw>#
* 每页记录数量 ~Q5HM
*/ Wp $\>
publicint getNum(){ *&s_u)b
return num; FsjblB3?E
} 7-)KTBFL
?~"RCZ[;.f
/** zK v}J
* if(num<1) num=1 TD<. :ul]
*/ 3 }XS|Y
publicvoid setNum(int num){ t V</x0#
if(num < 1) }I"^WCyH
num = 1; (Q&Z/Fe
this.num = num; kq+L63fZ
} HUH=Y;
hz!.|U@,{<
/** {dDU^7O
* 获得总页数 Q =Z-vTD+
*/ j1)w1WY0@
publicint getPageNum(){ *=rl<?tX
return(count - 1) / num + 1; {8eNQ-4I
} sqhM[u
k
}QK-@T@4<
/** o 0B`~7(
* 获得本页的开始编号,为 (p-1)*num+1 gO29:L[t
*/ \RJ428sxn
publicint getStart(){ w5p+Yx=q
return(p - 1) * num + 1; UWz<~Vy
} F{v+z8nW
NeYj[Q~xy
/** o&zeOJW
* @return Returns the results. #~"jo[
*/ iVE+c"c!2&
publicList<E> getResults(){ kAMt8
return results; czafBO6
} 0oD?4gn
b@Fa|>"_
public void setResults(List<E> results){ wNn6".S
this.results = results; wml`3$"cf
} s<:J(gD
-70Ut
4B
public String toString(){ .M04n\
StringBuilder buff = new StringBuilder >Tw|SK+3
|X>:"?4t
(); 5bk5EE`
buff.append("{"); 8D-g%Aj-
buff.append("count:").append(count); =73wngw
buff.append(",p:").append(p); uXXwMc<p
buff.append(",nump:").append(num); |,o!O39}>
buff.append(",results:").append c}QjKJ-c
Vx'_fb?wap
(results); BQsy)H`4E
buff.append("}"); 3vx?x39*Y
return buff.toString(); 8@ b83
} 1Ypru<.)W
rQU;?[y
} UPH:$Fk&
n<MH\.!tM
Xr-eDUEi