Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 E_z,%aD[
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 |jWA >S
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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 =(<7o_gJ
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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 Qc
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分页支持类: 1
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java代码: nwDW<J{f|U
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package com.javaeye.common.util; odvUU#l
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import java.util.List; Ac>GF
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publicclass PaginationSupport { TU| 0I
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publicfinalstaticint PAGESIZE = 30; >u`Ci>tY
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privateint pageSize = PAGESIZE; nzB!0U
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privateList items; ZI!;~q
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privateint totalCount; XQ Si
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privateint[] indexes = newint[0]; kgX"I ?>d
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privateint startIndex = 0; y0t-e
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public PaginationSupport(List items, int taSYR$VJ
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totalCount){ i?F~]8
setPageSize(PAGESIZE); ehX4[j6
setTotalCount(totalCount); KXo[;Db)k
setItems(items); {*Qx^e`h$.
setStartIndex(0); 6A} 45
} y|#Fu
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public PaginationSupport(List items, int {f>e~o
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totalCount, int startIndex){ x1`Jlzrp,
setPageSize(PAGESIZE); j+3=&PkA.]
setTotalCount(totalCount); )5U7w
setItems(items); ; JHf0
setStartIndex(startIndex); *_uGzGB&G
} `$VnB
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public PaginationSupport(List items, int ,5|@vW2@u
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totalCount, int pageSize, int startIndex){ |=Pw-uk
setPageSize(pageSize); ^+dL7g?+
setTotalCount(totalCount); o l+*Oe
setItems(items); Oyjhc<6
setStartIndex(startIndex); eKqo6P:#f
} W%}zwQ
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publicList getItems(){ sTYA
return items; OWHHN<
} GplEad
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publicvoid setItems(List items){ w5Yt mnP
this.items = items; `HM?Fc58
} -sk!XWW+
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publicint getPageSize(){ /.@"wAw:
return pageSize; 1&YkRCn0
} @w[HXb
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publicvoid setPageSize(int pageSize){ *f+DV[DF
this.pageSize = pageSize; <a%RKjQvT
} +@yTcz
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publicint getTotalCount(){ k iY1
return totalCount; Ne2eBmY}(
} s `
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publicvoid setTotalCount(int totalCount){ E$E#c8I:
if(totalCount > 0){ )ocr.wU@
this.totalCount = totalCount; ksli-Px
int count = totalCount / kt hy9<!$
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pageSize; eq$.np
if(totalCount % pageSize > 0) f5&K=4khn
count++; i~EFRI@
indexes = newint[count]; MJI`1*(
for(int i = 0; i < count; i++){ r1[Jo|4vo
indexes = pageSize * kTs.ps8ei
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} c`_[q{(^m
}else{ \zyvu7YA
this.totalCount = 0; OOj}CZ6
} 18gApRa
} O3["5
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publicint[] getIndexes(){ UB|}+WA3
return indexes; nK9?|@S*'
} o",J{
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publicvoid setIndexes(int[] indexes){ y^hCO:`l3
this.indexes = indexes; p`06%"#
} Lk1e{!a
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publicint getStartIndex(){ AqucP@
return startIndex; zqa7!ky
} FWDAG$K@0
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publicvoid setStartIndex(int startIndex){ 'o]8UD(
if(totalCount <= 0) zP|^) h5
this.startIndex = 0; |tuh/e@dx
elseif(startIndex >= totalCount) |'N)HH>;
this.startIndex = indexes [^2c9K^NK
0hM!#BU5K
[indexes.length - 1]; MI\35~JAN
elseif(startIndex < 0) {#4F}@Q
this.startIndex = 0; fy|$A@f
else{ x3Ze\N8w
this.startIndex = indexes &-hXk!A
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[startIndex / pageSize]; [e;c)XS[
} zM2_z
} 8a3h)R
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publicint getNextIndex(){ %{;1i
int nextIndex = getStartIndex() + 7HM%Cd
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pageSize; .I
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if(nextIndex >= totalCount) _%:$sAj
return getStartIndex(); |58xR.S'g
else VQwF9Iq]`
return nextIndex; Z=j6c"
} o3=pxU*
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publicint getPreviousIndex(){ 5V@c~1\
int previousIndex = getStartIndex() - 'j(F=9)
{Etvu
pageSize; g}n-H4LI
if(previousIndex < 0) db`L0JB
return0; Ws*UhJY<GS
else =a^}]k}
return previousIndex; :.aMhyh#*
} p;n"zr8U
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} D,P{ ,/
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抽象业务类 ,u_ Z0S M
java代码: u.dYDi
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/** m6Mko2
* Created on 2005-7-12 t4v@d
*/ @jY=b<
package com.javaeye.common.business; h'ik19
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import java.io.Serializable; 2xK v;
import java.util.List; y,s`[=CT
h yK&)y?~
import org.hibernate.Criteria; fs\A(]`$
import org.hibernate.HibernateException; ,8G6q_ud
import org.hibernate.Session; T7~H|%
import org.hibernate.criterion.DetachedCriteria; H5>?{(m
import org.hibernate.criterion.Projections; a&RH_L jM
import K*S3{s%UR
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org.springframework.orm.hibernate3.HibernateCallback; /odDJxJ
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import .bY
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org.springframework.orm.hibernate3.support.HibernateDaoS @8*lqV2
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upport; n#^ii/H
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import com.javaeye.common.util.PaginationSupport; 'e/wjV
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public abstract class AbstractManager extends dVe,;?+A
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HibernateDaoSupport { je85G`{DC
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privateboolean cacheQueries = false; <.".,Na(J0
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privateString queryCacheRegion; &&g02>gE
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publicvoid setCacheQueries(boolean r4m z
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cacheQueries){ %2y5a`b
this.cacheQueries = cacheQueries; KX
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} bEm9hFvd
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publicvoid setQueryCacheRegion(String 7@
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queryCacheRegion){ U0U y
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this.queryCacheRegion = EKus0"|
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queryCacheRegion; 7-gT:
} YS:p(jtd
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publicvoid save(finalObject entity){ EpH_v`
getHibernateTemplate().save(entity); $[UUf}7L
} wJj:hA}
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publicvoid persist(finalObject entity){ -Xx4:S
getHibernateTemplate().save(entity); pX+4B=*
} S$ffTdRz
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publicvoid update(finalObject entity){ T+e*' <!O
getHibernateTemplate().update(entity); .cm2L,1h
} ocu,qL)W
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publicvoid delete(finalObject entity){ [ ou$*
getHibernateTemplate().delete(entity); y @S_CB47
} iX[g
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publicObject load(finalClass entity, <RKT
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finalSerializable id){ @VPmr}p:{
return getHibernateTemplate().load u*/+cT
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(entity, id); PMUW<UI
} *YSRZvD<\
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publicObject get(finalClass entity, jD${ZIv
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finalSerializable id){ Re&"Q8I.8
return getHibernateTemplate().get M*f]d`B
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(entity, id); s VHk;:e>x
} sn"z'=ch
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publicList findAll(finalClass entity){ hD=.rDvO
return getHibernateTemplate().find("from |c^ ?tR<
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" + entity.getName()); <v'&Pk<
} )U=]HpuzI
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publicList findByNamedQuery(finalString YZ`SF"Bd(
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namedQuery){ :AS`1\ C
return getHibernateTemplate K8R>O *~
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().findByNamedQuery(namedQuery); Q;J(
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} S*$?~4{R
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publicList findByNamedQuery(finalString query, `CI_zc=jx
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finalObject parameter){ xJ2I@*DN
return getHibernateTemplate a|"Uw
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().findByNamedQuery(query, parameter); yOt#6Vw
} 1[T7;i$
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publicList findByNamedQuery(finalString query, _&/ {A|n
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finalObject[] parameters){ B0%=! &
return getHibernateTemplate [orL.D]
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().findByNamedQuery(query, parameters); }zx
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} VX&PkGi?o
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publicList find(finalString query){ )Qd
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return getHibernateTemplate().find |?ssHW
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(query); !3Pbu=(cte
} ~7 U~
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publicList find(finalString query, finalObject naW!b&:
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parameter){ Id##367R
return getHibernateTemplate().find y;uR@{
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(query, parameter); t2s/zxt
} 10i$ b<O
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public PaginationSupport findPageByCriteria +l/v`=C
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(final DetachedCriteria detachedCriteria){ :Ys~Lt54
return findPageByCriteria VOLj#H
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); avL_>7q
} =jJEl=*S
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public PaginationSupport findPageByCriteria qQi\/~Y[:
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(final DetachedCriteria detachedCriteria, finalint 6:O<k2=2
}}{n|l+R5
startIndex){ weSq|f
return findPageByCriteria kB> ~Tb0
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(detachedCriteria, PaginationSupport.PAGESIZE, o[T+/Ej&
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startIndex); <ZF|2
} r~lZ8$KC
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public PaginationSupport findPageByCriteria 0{|HRiQH9+
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(final DetachedCriteria detachedCriteria, finalint `daqzn
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pageSize, WXl+w7jr
finalint startIndex){ )&Oc7\J,
return(PaginationSupport) \ph.c*c
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getHibernateTemplate().execute(new HibernateCallback(){ =O![>Fu5
publicObject doInHibernate @)?]u
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(Session session)throws HibernateException { );\c{QF
Criteria criteria = AQlB_@ b
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detachedCriteria.getExecutableCriteria(session); FT@uZWgQ=
int totalCount = M
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((Integer) criteria.setProjection(Projections.rowCount ^AS\a4`/
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()).uniqueResult()).intValue(); #Ub_m@@4
criteria.setProjection hTr5Q33y>
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(null); 6'r8.~O
List items = DPTk5o[
$'498%K2
criteria.setFirstResult(startIndex).setMaxResults t'vt'[~,U
qW0:q.
(pageSize).list(); sQvRupYRO
PaginationSupport ps = ]
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new PaginationSupport(items, totalCount, pageSize, 6<._^hyq
"6$V1B0KW
startIndex); a>'ez0C
return ps; @1JwjtNk
} hj [77EEz
}, true); <U@N^#
} [y[d7V9_o
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public List findAllByCriteria(final O1J&Lwpk,
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DetachedCriteria detachedCriteria){ i2~uhGJ
return(List) getHibernateTemplate <Kd(fFe
Q +^&
().execute(new HibernateCallback(){ V&M*,#(?
publicObject doInHibernate 3'0Pl8
=?<WCR
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(Session session)throws HibernateException { `Vb
Criteria criteria = ]:<!(
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detachedCriteria.getExecutableCriteria(session); dAh.I3
return criteria.list(); cz>,sz~i
} r9i?H
}, true); %lF*g
} E-bswUVaEE
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public int getCountByCriteria(final tS'lJu
/ (&E
DetachedCriteria detachedCriteria){ _FY&XL=
Integer count = (Integer) Fb5U@X/vE
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getHibernateTemplate().execute(new HibernateCallback(){ 0
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publicObject doInHibernate Ts5)r(
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(Session session)throws HibernateException { &S,D;uhF
Criteria criteria = UN]gn>~j
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detachedCriteria.getExecutableCriteria(session); A`c%p7Z%
return KP&+fDa
{ mi}3/
criteria.setProjection(Projections.rowCount ,=:K&5mCv
+$dJA
()).uniqueResult(); z%;plMj
} ~VGnE:
}, true); kQ`tY`3F
return count.intValue(); *'<AwG&
} ?+yr7_f3*
} mmAm@/
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用户在web层构造查询条件detachedCriteria,和可选的 m&.LJ*uM\K
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 4T@:_G2b
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PaginationSupport的实例ps。 :t}\%%EbmE
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ps.getItems()得到已分页好的结果集 )pB#7aEw
ps.getIndexes()得到分页索引的数组 P6:9o}K6
ps.getTotalCount()得到总结果数 CVj^{||eF
ps.getStartIndex()当前分页索引 $~/2!T_
ps.getNextIndex()下一页索引 RJrz ~,}
ps.getPreviousIndex()上一页索引 SK<Rk
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 Wv;0PhF
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,尤其是上面的示例代码,让我着实觉得该对我原来的分页查询做 (m~>W"x/
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一下代码重构了。 D tsZP
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我把原本我的做法也提供出来供大家讨论吧: M&Uy42,MR
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首先,为了实现分页查询,我封装了一个Page类: 2w?q7N%
java代码: 44]s`QyG
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/*Created on 2005-4-14*/ @KN+)q P
package org.flyware.util.page; #lYyL`B+~
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/** uZqL'l+/y
* @author Joa B=_w9iVN
* o`U}uqrO
*/ ZlT }cA/n
publicclass Page { pu-HEv}]a|
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/** imply if the page has previous page */ x.Sf B[SZ
privateboolean hasPrePage; i'>6Qo
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/** imply if the page has next page */ =Tj{)=^/#
privateboolean hasNextPage; &,X}M
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/** the number of every page */ ("$/sT
privateint everyPage; `MtzA^X r
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/** the total page number */ OgQdyU
privateint totalPage; ]?9*Vr:P^
nL@'??I1
/** the number of current page */ mypV[
privateint currentPage; BI'>\hX/V
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/** the begin index of the records by the current _y@28t
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query */ ]\E"oZ
privateint beginIndex; lZFu|(
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@HT\Y%E
/** The default constructor */ =|3BkmO
public Page(){ "J VIkC
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} L9GLjRp-
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/** construct the page by everyPage Y
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* @param everyPage /K=OsMl2b8
* */ u4x-GObJM
public Page(int everyPage){ L2}\Ah"[
this.everyPage = everyPage; /6x&%G:m#
} 8 Rx@_
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/** The whole constructor */
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public Page(boolean hasPrePage, boolean hasNextPage, OO:S2-]Y>e
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int everyPage, int totalPage, Sj+H{xJi
int currentPage, int beginIndex){ g4K+AK
this.hasPrePage = hasPrePage; 'aSsyD!?<
this.hasNextPage = hasNextPage; +^.Yt0}
this.everyPage = everyPage; ,Qj G|P
this.totalPage = totalPage; ~_ THvx1
this.currentPage = currentPage; 0~|0D#klB
this.beginIndex = beginIndex; Z8v\>@?5R
} 4:/]Y=)x
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/** ~i,d%a
* @return _O`prX.:B0
* Returns the beginIndex. w$]G$e
*/ P,v7twc0M
publicint getBeginIndex(){ r!r08yf
return beginIndex; xfk
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} ($di]lbsT
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/** dOjly,!
* @param beginIndex rH}|~
* The beginIndex to set. $LP(\T([
*/ D
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publicvoid setBeginIndex(int beginIndex){ V@'Xj .ze
this.beginIndex = beginIndex; l@`k:?
} d i\.*7l?
}7PJr/IuF
/** t]xz7VQ
* @return &3vm
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* Returns the currentPage. > ,6
*/ 1[P}D~ nQ
publicint getCurrentPage(){ pa-*&p
return currentPage; kZ9Gl!g
} x{H+fq,M
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/** ib,`0=0= O
* @param currentPage 6IqPZ{g9K'
* The currentPage to set. u`ir(JIj]
*/ 8mX!mYO3c
publicvoid setCurrentPage(int currentPage){ +3,7 Apj
this.currentPage = currentPage; Th_@'UDa
} Agd"m4!
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/** {O+T`;=)L
* @return Laj/~Ru6
* Returns the everyPage. L*0YOE%=]
*/ pH~\~
publicint getEveryPage(){ 4LSs WO<@
return everyPage; | W@ ~mrO
} N"9^A^w8k
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/** ^-%'ItVO
* @param everyPage 8vx
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* The everyPage to set. "6,fIsU
*/ \8(Je"S
publicvoid setEveryPage(int everyPage){
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this.everyPage = everyPage; >~g-
} F:zmO5L5
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/** )U/Kz1U
* @return L7ae6#5.
* Returns the hasNextPage. 5;`Ot2
*/ kEh9J>|M
publicboolean getHasNextPage(){ Wvb ~j
return hasNextPage; /&6{}n
} 6;E3|st1X
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/** +9/K|SB{$
* @param hasNextPage l!1_~!{y
* The hasNextPage to set. lz^Vi!|p
*/ uh\G6s!4/
publicvoid setHasNextPage(boolean hasNextPage){ 5K
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this.hasNextPage = hasNextPage;
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} BOpZ8p'eH1
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/** 4 95Y<x}=
* @return 65Z}Hf
* Returns the hasPrePage. gX"
*/ >{AE@@PB^
publicboolean getHasPrePage(){
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return hasPrePage; (-ELxshd
} 6+=_p$crMx
!\ b-Ot(
/** j32*9
* @param hasPrePage taDe^Istj
* The hasPrePage to set. 8{Wl
*/ +B{u,xgg
publicvoid setHasPrePage(boolean hasPrePage){ ybpOk
this.hasPrePage = hasPrePage; "]3o933D
} 7a[6@
p$"~vA .
/** !S~)U{SSK
* @return Returns the totalPage. "yymnIQ3u
* Q``1^E'
*/ OcB&6!1u
publicint getTotalPage(){ Av.`'.b
return totalPage; j6s j 2D
} Z71_D
{~&]
/** V 2Xv)
* @param totalPage Zl[EpXlZ
* The totalPage to set. "tT4Cb3
*/ PU%Zay
publicvoid setTotalPage(int totalPage){ R(t%/Hvs$
this.totalPage = totalPage; vdXi'<
} =pzTB-G
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} lP=,|xFra
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,7$&gx>2&
上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 e!=7VEB
w#2apaz
个PageUtil,负责对Page对象进行构造: >'n[B
java代码: sc t3|H#
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/*Created on 2005-4-14*/ em7L`,
package org.flyware.util.page; pPxgjX
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import org.apache.commons.logging.Log; 0aq{Y7sYU
import org.apache.commons.logging.LogFactory; J+CGhk
W +Piqf*
/** E 9Kp=3H
* @author Joa "[/W+&z[~
* (]k Q9}8
*/ g3s5ra[
publicclass PageUtil { ?i_2ueVR
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privatestaticfinal Log logger = LogFactory.getLog t(<k4 ji,
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(PageUtil.class); IUAe6
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/** 2K3j3 |T
* Use the origin page to create a new page l _2Xao$
* @param page &n]v
* @param totalRecords -7oIphJ=\
* @return Z9H2! Cp
*/ ^0"fPG`
publicstatic Page createPage(Page page, int GRpwEfG
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totalRecords){ m
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return createPage(page.getEveryPage(), "cS7E5-|
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page.getCurrentPage(), totalRecords); |0^IX
} ;"f9"
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/** R,7.o4Wt
* the basic page utils not including exception p%Q{Rqc)
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handler x`2dN/wDhf
* @param everyPage ;B<rw^h5
* @param currentPage +
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* @param totalRecords Tq^B>{S"
* @return page (^T}6t3+4
*/ ZCK#=:ln
publicstatic Page createPage(int everyPage, int ^-Ks_4
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currentPage, int totalRecords){ )4ok@^.
everyPage = getEveryPage(everyPage); {
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currentPage = getCurrentPage(currentPage); F:Vl\YZ
int beginIndex = getBeginIndex(everyPage, , iEGf-!k
8~!h8bkC
currentPage); dr8Q>(ZY
int totalPage = getTotalPage(everyPage, MB5V$toC
>!PM5%G
totalRecords); mE+=H]`.p
boolean hasNextPage = hasNextPage(currentPage, PMiu "
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totalPage); $v8T%'p+
boolean hasPrePage = hasPrePage(currentPage); 3]NKAPY
1)e[F#|
returnnew Page(hasPrePage, hasNextPage, lq1223
everyPage, totalPage, V1i^#;
currentPage, #cikpHLXG
"<L9-vb
beginIndex); gjJ:s,Fg
} W;X:U.
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privatestaticint getEveryPage(int everyPage){ 1JS5 LS
return everyPage == 0 ? 10 : everyPage; 7wrRIeES
} t|&hXh{
rWL&-AZQl
privatestaticint getCurrentPage(int currentPage){ < A`srmS?
return currentPage == 0 ? 1 : currentPage; )):D&wlq
} ()Img.TIt
RR`\q>|
privatestaticint getBeginIndex(int everyPage, int zYis~+
D.F1^9Q
currentPage){ pm}_\_
return(currentPage - 1) * everyPage;
1[Q~&QC
} W$}2
$}r0U
9y\Ik/
privatestaticint getTotalPage(int everyPage, int UOe@R|79q
|o_
N$70
totalRecords){ 3! KyO)8
int totalPage = 0; p%Ns
f[1>
So NgDFD
if(totalRecords % everyPage == 0) wG 5H^>6u>
totalPage = totalRecords / everyPage; [MAvU?;
else vA?3kfL|#
totalPage = totalRecords / everyPage + 1 ; }y|_v^
1LmbXH]%
return totalPage; #E/|WT
} H'@@%nO(
Z4k'c+
privatestaticboolean hasPrePage(int currentPage){ (>\4%(pnD
return currentPage == 1 ? false : true; ;M O,HdP;
} =EHKu|rX~
4E$6&,\
privatestaticboolean hasNextPage(int currentPage, ?R@u'4yK
V4*/t#L/
int totalPage){ bM,%+9oz;
return currentPage == totalPage || totalPage == Z%{`j!!p
}o=s"0 a
0 ? false : true; }F_=.w0
} q' t"
@Bsvk9}
9 b&HqkXX
} PmUq~YZ7
e=i9l
dY?>:ce
()_^:WQO?
xn<x/e
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 w\>@>*E>
T#YJ5Xw
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 F@xKL;'N74
|x ir93 |
做法如下: 9+'*
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 2 o5u02x
z7JhS|
的信息,和一个结果集List: xc?=fv
java代码: `!
)^g/>0i
NE?tfj
JPe<qf-
/*Created on 2005-6-13*/ ,/-DAo~O
package com.adt.bo; RPTIDA))
u0Opn=(_
import java.util.List; 8J0#lu
&*qAB)**
import org.flyware.util.page.Page; ou\~^
kybDw{(}gc
/** jrO{A3<E
* @author Joa B5qlU4km&
*/ Tu=~iQ
publicclass Result { *5" )3\/
j-/F*P
private Page page; YZc{\~d
1{CVd m<9
private List content; nhB.>ReAi
TdrRg''@
/** m>^#:JK
* The default constructor BK foeN)%
*/ q!) nSD
public Result(){ A{wSO./3
super(); 5eX+9niY
} 7;ddzxR4
M^y5 Dep
/** 1v9#Fr Y
* The constructor using fields <)$JA
* T:VFyby\w
* @param page _sqV@ J
* @param content $_u)~O4$
*/ kXZG<?
public Result(Page page, List content){ }\.Z{h:t
?
this.page = page; $$---Y
this.content = content; :w26d-QR(
} ?_@Mg\Hc
QjFE
/** CQET
* @return Returns the content. 82w=t
*/ $+w -r#,
publicList getContent(){ fsV_>5I6
return content; *|.-y->
} a(K^/BT
NfXEW-
/** oedLe9!
* @return Returns the page. R?J=5tO
*/ hR~~k~84
public Page getPage(){ -Z&9pI(3R~
return page; ^r^) &]
} O`'r:W
1y6{3AZm<
/** 5H/D~hr&
* @param content c~n:xblv
* The content to set. <):= mr7
*/ ;
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public void setContent(List content){ Y2P%0
this.content = content; l#!6
tw+e?
} +Am\jsq
KOVR=``"/
/** R}0!F2
* @param page
mI3
\n
* The page to set. f VpE&F
*/ {h}e 9
publicvoid setPage(Page page){ Q1u/QA:z7
this.page = page; >WYradLUi
} 4
JDk()
} =LojRY
]"-c?%L
.#}`r`/
94GF8P
LVxR*O
2. 编写业务逻辑接口,并实现它(UserManager, Et+W LQ6)
7eQc14
UserManagerImpl) C?7I(b:
java代码: ^Z:qlYZ
*waaM]u
H4IJLZ3G
/*Created on 2005-7-15*/ U9:I"f,
package com.adt.service; }^n346^
pJ3Yjm[l
import net.sf.hibernate.HibernateException; (z.eXo P@>
ibQN
p Iz
import org.flyware.util.page.Page; M}xyW"yp
C *U,$8j|}
import com.adt.bo.Result; cP`[/5R
H+F>#
/** xPorlX)zW
* @author Joa f|'8~C5I@>
*/ @0U={qX
publicinterface UserManager { .u$o^; z!
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:#okt
public Result listUser(Page page)throws #Bi8>S
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HibernateException; ad,pHJ`
;]sbz4?
} &u~#bDh
clO9l=g
(|.rEaTA[1
oS Apa
<t"|wYAa_
java代码: IO}53zn<l
wJu,N(U
vC>8:3Zaq
/*Created on 2005-7-15*/ eeu;A,@U
package com.adt.service.impl; Q,<V)
VVDd39q
import java.util.List; oeIza<:=R
o=y0=,:a?9
import net.sf.hibernate.HibernateException; _"688u'88
o-r00H|
import org.flyware.util.page.Page; Z@QJ5F1y
import org.flyware.util.page.PageUtil; ylwh_&>2
H&E3RU>`
import com.adt.bo.Result; ^% jk. *
import com.adt.dao.UserDAO; F%^)oQT+c
import com.adt.exception.ObjectNotFoundException; s 8iB>-dk
import com.adt.service.UserManager; 7dtkylW
\S[I:fw#&
/** kP,^c{
* @author Joa Xjs`iK=w
*/ #f-pkeaeq
publicclass UserManagerImpl implements UserManager { r`5svY
I*hzlE
private UserDAO userDAO; r%UsUj
l/g6Tv`w
/** .}ePm(
* @param userDAO The userDAO to set. d}--}&r
*/ a5nA'=|}i
publicvoid setUserDAO(UserDAO userDAO){ FoB^iA6e
this.userDAO = userDAO; gvu1
} l[u=_uaYl
.LA?2N
/* (non-Javadoc) zyPc<\HoK
* @see com.adt.service.UserManager#listUser $fFh4O4
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(org.flyware.util.page.Page) 9L9qLF5 t
*/ g8L{xwx<
public Result listUser(Page page)throws 1%`Nu ]D
EEdU\9DH(
HibernateException, ObjectNotFoundException { SKeX~uLz
int totalRecords = userDAO.getUserCount(); w$4*/D}Y
if(totalRecords == 0) {dXmSuO
throw new ObjectNotFoundException }(/\vTn*1
c4Wl^E8
("userNotExist"); ?{rpzrc!*
page = PageUtil.createPage(page, totalRecords); cbaa*qoU
List users = userDAO.getUserByPage(page); O
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returnnew Result(page, users); ViYfK7Z
} Vh'H =J
SBh"^q
} L5 Q^cY]p
jHQnD]Hr
j`:D BO&)\
P]%)c6Uh
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其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 J1g+H2
Eu|O<9U\
询,接下来编写UserDAO的代码: S:8 WBY] M
3. UserDAO 和 UserDAOImpl: H?cJ'Q,5
java代码: br%l>Y\"
x".!&5
lFZl}x
/*Created on 2005-7-15*/ Q%!Dk0-)
package com.adt.dao; %_%BbQf
E(g$f.9
import java.util.List; *"Uf|
L6Io u
import org.flyware.util.page.Page; $(+#$F<eo+
V[2}
import net.sf.hibernate.HibernateException; +sT S1t
/X;/}fk
/** Ld?'X=eQ
* @author Joa Jp"yb`w
*/ o1Nfn'!3/>
publicinterface UserDAO extends BaseDAO { LDh,!5G-M
Yan}H}Oq
publicList getUserByName(String name)throws 9Yd"Y-
`lA_knS
HibernateException; :JIJ!Xn)
>PK 6CR
publicint getUserCount()throws HibernateException; u\Y3h:@u
H*HL:o-[
publicList getUserByPage(Page page)throws qPoN 8>.
bCqTubbx!t
HibernateException; L30$
xO&qo8*
} " 6ScVa5)
.,F`*JVFq
aUk]wiwIR9
2#oU2si
JA~q}C7A7o
java代码: Lu
CiO
N;gY5;0m
$i@I|y/
/*Created on 2005-7-15*/ Y.kgJ #2
package com.adt.dao.impl; 0Ua&_D"
PUmgcMt
import java.util.List; 2p~}<B
OJiwI)a9
import org.flyware.util.page.Page; lokKjs
9DdR"r'7
import net.sf.hibernate.HibernateException; nh*6`5yj
import net.sf.hibernate.Query; ksf6O$
ZvwU
import com.adt.dao.UserDAO; *vzEfmN:d
}0,dG4Oo=
/** D)tL}X$
* @author Joa mDx=n.lIz
*/ SHT`
public class UserDAOImpl extends BaseDAOHibernateImpl ![9$ru
-&l%CR,U
implements UserDAO { {gh<SZsE
+kN,OK~
/* (non-Javadoc) Zc'^iDAY
* @see com.adt.dao.UserDAO#getUserByName % {-r'Yi%
2"HG6"Rr
(java.lang.String) 5W0s9yD
*/ C8x9 Jrc
publicList getUserByName(String name)throws -Fq`#"
cn: L]%<
HibernateException { 60 %VG
String querySentence = "FROM user in class S~bhh&
C\4d.~C:w3
com.adt.po.User WHERE user.name=:name"; BA[ uO3\4
Query query = getSession().createQuery #p
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#\
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(querySentence); UA|\D]xe
query.setParameter("name", name); 6-z(34&N
return query.list(); (D:-p:q.
} `<{LW>Lb
w{ ;Sp?Os
/* (non-Javadoc) \SoT^PW
* @see com.adt.dao.UserDAO#getUserCount() ..zX
*/ {Fqwr>e
publicint getUserCount()throws HibernateException { 5'( T*"
int count = 0; HX)]@qL
String querySentence = "SELECT count(*) FROM IXG@$O?y/
$6(a6!
user in class com.adt.po.User"; !nq`Py MR
Query query = getSession().createQuery C`R<55x6
Xmi~fie
(querySentence); qV;I<AM
count = ((Integer)query.iterate().next 9J?lNq
ltlo$`PR
()).intValue(); hw.>HT|.N
return count; bYoBJ
#UX
} 8
/%{xB^
w51l;2$des
/* (non-Javadoc) !FD d5CS
* @see com.adt.dao.UserDAO#getUserByPage I,<?Kv
=Z{jc
(org.flyware.util.page.Page) $s4.Aj
*/ @meT8S9t
publicList getUserByPage(Page page)throws 2W2T
TMo DN%{
HibernateException { I$MlIz$l v
String querySentence = "FROM user in class yM7Iq)o6u
/!MVpi'6&
com.adt.po.User"; ``eam8Az_U
Query query = getSession().createQuery ,@/O\fit)
\m%c"'[
(querySentence); QM*
T?PR
query.setFirstResult(page.getBeginIndex()) H>W8F2VT
.setMaxResults(page.getEveryPage()); fERO(o
return query.list(); Xhq6l3 M
} M9""(`U
;b:'i&r
} 5\=
y9Z- x
N.H<'Q8&
/&<V5?1|
O@4 J=P=w
PR]b]=
至此,一个完整的分页程序完成。前台的只需要调用 Wa7wV
9
SZyORN
userManager.listUser(page)即可得到一个Page对象和结果集对象 N#ZWW6
k}p8"'O
的综合体,而传入的参数page对象则可以由前台传入,如果用 $dXx@6fP
%B( rW?p&
webwork,甚至可以直接在配置文件中指定。 Uqb]&2
Dk>6PBl
下面给出一个webwork调用示例: ".%d{z}vz
java代码: IRwtM'%0
.izq}q*P
JSi0-S[Y{
/*Created on 2005-6-17*/ k_!e5c
package com.adt.action.user; fIl!{pv[
jw9v&/-
import java.util.List; ]ly" K!1,
GGhk~H4OP
import org.apache.commons.logging.Log; i#hFpZ6u
import org.apache.commons.logging.LogFactory; 92t.@!m`
import org.flyware.util.page.Page; -fl6M-CYX
7KX27.~F
import com.adt.bo.Result; o{! :N> (
import com.adt.service.UserService; ! xG*W6IT
import com.opensymphony.xwork.Action; \Dy|}LE
A+gS'DZ9C
/** IhBc/.&RL
* @author Joa p7@R+F\.};
*/ ~!5=o{wy
publicclass ListUser implementsAction{ rv(?%h`
2jC` '8
privatestaticfinal Log logger = LogFactory.getLog :>2wVN&\c
!&>`
(ListUser.class); (/N&_r4x
q:TNf\/o
private UserService userService; pm ,xGo2
"GQ Q8rQ
private Page page; P3: t
4^
?q9]H5\
privateList users; [#q]B=JB
BhzD V
/* <y] 67:"<v
* (non-Javadoc) QcW8A ,\q
* `vgaX,F*
* @see com.opensymphony.xwork.Action#execute() UJSIbb5
*/ 8ZVQM7O
publicString execute()throwsException{ a
\1QnCy
Result result = userService.listUser(page); %Qlc?Wl:
page = result.getPage(); %:d7Ts&?Z
users = result.getContent(); jt on \9
return SUCCESS; ESIP+
} U`i5B;k}-
+q'1P}e
/** 26rg-?;V^
* @return Returns the page. kuy?n-1g
*/ xF8n=Lc
public Page getPage(){ cQyN@W
return page; z'_Fg0kR{
} qrYbc~jI7
uW(-?
/** jRg
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* @return Returns the users. Td|u@l4B
*/ GQn:lu3j:
publicList getUsers(){ oNyYx6q:Q
return users; WC`h+SC`.
} ?gl&q+mv
G/<zd)
/** #BUq;5
* @param page "mW'tm1+
* The page to set. oNAnJ+_
*/ igfQ,LWe!
publicvoid setPage(Page page){ |(z{)yWbC[
this.page = page; b4e~Z
} %- 540V{q
*y?HaU
/** #`*uX6C
* @param users j#n ]q{s4
* The users to set. {,Q )D$i
*/ phuiLW{&
publicvoid setUsers(List users){ *9EwZwE_K
this.users = users; Yt]`>C[|D
} 2!J#XzR0W
II=`=H{
/** 7 H
* @param userService y9 {7+]
* The userService to set. %Hbq3U30
*/ ~R
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publicvoid setUserService(UserService userService){ T+}|$/Tv
this.userService = userService; 'K ?h6?#
} S)W xTE9
} RW. qw4
9efDM
&-yRa45?
DQQ]grU
6DHK&<=D8
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, SN}K=)KF#
DWt|lO
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 K6IT$$g
.[O{,r
么只需要: lPR=C0h}@
java代码: szsVk#p
Sv n7.Ivep
|q*yuK/
<?xml version="1.0"?> L1SKOM$
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork .KA-=$~J1
[`\VgKeu
1.0//EN" "http://www.opensymphony.com/xwork/xwork- AOR?2u
i<^X z
1.0.dtd"> L7C ;l,ot
s|Mo3_>
<xwork> |u>(~6
x.+T65X~4
<package name="user" extends="webwork- %R c#/y
JY,$B-l
interceptors"> Zd[rn:9\
_`udd)Y2
<!-- The default interceptor stack name Z!"-LQJ
k<< x}=
--> VhUWws3E
<default-interceptor-ref m^3x%ENZ
\)~d,M}kK
name="myDefaultWebStack"/> el9P@r0
mAW.p=;
<action name="listUser" r N$0qo
Fc1!i8vv
class="com.adt.action.user.ListUser"> F/s
n"2
<param w \b+OW
wXQxZuk[
name="page.everyPage">10</param> YhN<vZ}U!~
<result Z=a%)Ki?Ag
"]S
name="success">/user/user_list.jsp</result> O
k`}\NZL
</action> yJ $6vmQ
_re# b?
</package> 4Hj)Av<O(
c;VqEpsbl
</xwork> 'Lrn<
9eMle?pF
G"<#tif9K
7?Wte&C];p
..)J6L5l
$l]:2!R
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 qIi
\[Ugh
_i05'_
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。 PILpWhjL$9
A &