Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 3ADTYt".
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 hV/$6 8A_
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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 vW
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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 6)kF!/J
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分页支持类: RZ9vQ\X
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java代码: ?ZDXT2b~~
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package com.javaeye.common.util; W~
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import java.util.List; Qi#%&Jz>f
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publicclass PaginationSupport { \aQBzEX
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publicfinalstaticint PAGESIZE = 30; Ps(3X@
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privateint pageSize = PAGESIZE; V=BF"S;-'
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privateList items; W`K XO|'p@
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privateint totalCount; Xz&Hfs"/J
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privateint[] indexes = newint[0]; $%"i|KTsv:
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privateint startIndex = 0; +.whEw(i
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public PaginationSupport(List items, int R$4&>VBu
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totalCount){ k!b\qS~Q
setPageSize(PAGESIZE); 11}X2j~Ww
setTotalCount(totalCount); _ro^<V$%
setItems(items); _9wX8fh3D
setStartIndex(0); g8
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}
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public PaginationSupport(List items, int }BS.OK?
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totalCount, int startIndex){ 7R[4XQ%
setPageSize(PAGESIZE); mS5'q q;t
setTotalCount(totalCount); }(z[
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setItems(items); }$s#H{T!
setStartIndex(startIndex); oE[wOq+
} W#E`h
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public PaginationSupport(List items, int Uc%(#I]Mi
kB{
totalCount, int pageSize, int startIndex){ 3r!6Z5P7{'
setPageSize(pageSize); B>*zQb2:
setTotalCount(totalCount); Ikql
setItems(items); y{+$B
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setStartIndex(startIndex); aa2&yc29hp
} lfp[(Ph)9
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publicList getItems(){ a7s+l=
return items; =<R")D]4z
} e`zx#v
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publicvoid setItems(List items){ 6z=h0,Y}
this.items = items; F]DRT6)
} t+7h(?8L
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publicint getPageSize(){ 'g.9
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return pageSize; +?Vj}p;
} a~E@scD
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publicvoid setPageSize(int pageSize){ b9Jah
this.pageSize = pageSize; "S)2<tV
} @TF^6)4f
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publicint getTotalCount(){ _L
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return totalCount; wZB:7E%
} |^9+c2
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publicvoid setTotalCount(int totalCount){ P"d7Af
if(totalCount > 0){ vFKX@wV S
this.totalCount = totalCount; Otq`4 5
int count = totalCount / D#Qfa!=g
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pageSize; 8w1TX [b
if(totalCount % pageSize > 0) z{XN1'/V
count++; ev~/Hf
indexes = newint[count]; ZS&>%G
for(int i = 0; i < count; i++){ b-4gHW
indexes = pageSize * xuBXOr4"P
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} ]gHxvT\E
}else{ 4C AV)
this.totalCount = 0; "9F]Wv/
} R-odc,P=
} &%J+d"n(
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publicint[] getIndexes(){ T.ZPpxY
return indexes; A8Z2o\+
} UrAg*v!Qy
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publicvoid setIndexes(int[] indexes){ CbPCj.MH
this.indexes = indexes; o=/Cje
} @L?X}'0xI4
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publicint getStartIndex(){ ]LGp3)T-
return startIndex; 6 0C;J!D
} -anLp8G*
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publicvoid setStartIndex(int startIndex){ }m '= _u
if(totalCount <= 0) |GmV1hN
this.startIndex = 0; !r=^aa(\
elseif(startIndex >= totalCount) 9{OH%bF
this.startIndex = indexes >y
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[indexes.length - 1]; PqOy"HO
elseif(startIndex < 0) }qf9ra
this.startIndex = 0; NpmPm1Ix .
else{ 7lP3\7wD@9
this.startIndex = indexes !AR$JUnX
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[startIndex / pageSize]; *~p~IX{
} c k~gB
} 5f54E|vD
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publicint getNextIndex(){ G5^gwG+
int nextIndex = getStartIndex() + m~K[+P
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pageSize; m7:E73:
if(nextIndex >= totalCount) , N:'Z
return getStartIndex(); E\M{/.4 4
else tE)%*z@<Lt
return nextIndex; 4fDo }~
} >M` swEj
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publicint getPreviousIndex(){ vS~y~ uU%6
int previousIndex = getStartIndex() - f;/t7=>d
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pageSize; ;OYwZ
if(previousIndex < 0) "Y&+J@]
return0; //--r5Q
else T7;)HFGeW
return previousIndex; {Y5h*BD>
} ?Az pb}#
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} nsyg>=j
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抽象业务类 kO<`RHlX=
java代码: *$(=I6b
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/** m[^;HwJ
* Created on 2005-7-12 {nQ}t
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*/ ;{|a~e?Y
package com.javaeye.common.business; JxQwxey{
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import java.io.Serializable; Q:+Y-&||"
import java.util.List; ^v3+w"2
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import org.hibernate.Criteria; tC+9W1o
import org.hibernate.HibernateException; 1at$_\{.(
import org.hibernate.Session; ^a`zvrE
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import org.hibernate.criterion.DetachedCriteria; Y=G *[G#
import org.hibernate.criterion.Projections; *9^CgLF
import |PN-,f{ -
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org.springframework.orm.hibernate3.HibernateCallback; 4\(;}M-R{
import 8O{]ML
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org.springframework.orm.hibernate3.support.HibernateDaoS 89l_%To
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upport; SU#
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import com.javaeye.common.util.PaginationSupport; cXJgdBwo
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public abstract class AbstractManager extends r"fu{4aX
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HibernateDaoSupport { @
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privateboolean cacheQueries = false; svpWABO
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privateString queryCacheRegion; cb%w,yXw
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publicvoid setCacheQueries(boolean ^e>v{AE%
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cacheQueries){ -I=}SZ
this.cacheQueries = cacheQueries; ]^
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} Rl5}W\&
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publicvoid setQueryCacheRegion(String ;JL@V}L,
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queryCacheRegion){ 62(WZX%b
this.queryCacheRegion = YSrFHVq
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queryCacheRegion; A v2 _A
} ZQBo|8*
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publicvoid save(finalObject entity){ XVv7W5/q]
getHibernateTemplate().save(entity); I:6xDDpZG`
} 2:DpnLU5
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publicvoid persist(finalObject entity){ *fd` .}
getHibernateTemplate().save(entity); c7rYG]
} tb=L+WAIw
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publicvoid update(finalObject entity){ T!a8c<'V
getHibernateTemplate().update(entity); )i!)Tv
} dfJ7Dhn
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publicvoid delete(finalObject entity){ ]`4QJ;#
getHibernateTemplate().delete(entity); -x_iqrB
} h,p&/oU4U
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publicObject load(finalClass entity, #&8Opo(
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finalSerializable id){ v<c Hx/
return getHibernateTemplate().load '\_)\`a|
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(entity, id); {W4t]Ff
} EEo+#
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publicObject get(finalClass entity, ^y6CV4T+
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finalSerializable id){ (CV=0{]
return getHibernateTemplate().get Bpp9I;)c
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(entity, id); PQ(%5c1e
} #62ww-E~
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publicList findAll(finalClass entity){ VN".NEL
return getHibernateTemplate().find("from J~Ph)|AiS
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" + entity.getName()); vSL{WT]m
} U{}7:&As
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publicList findByNamedQuery(finalString Oxvw`a#
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namedQuery){ ;Dgp
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return getHibernateTemplate CyU>S}t
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().findByNamedQuery(namedQuery); [eN{Ft0x
} O^$Zz<
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publicList findByNamedQuery(finalString query, sg2C_]i,H
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finalObject parameter){ ?(=B=a[
return getHibernateTemplate tSYnc7
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().findByNamedQuery(query, parameter); <>oW f
} ?yb{DZ46
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publicList findByNamedQuery(finalString query, "8]170
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finalObject[] parameters){ u5ygbCm
return getHibernateTemplate E=QQZ\w
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().findByNamedQuery(query, parameters); 463dLEd
} |{K:.x#^
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publicList find(finalString query){ a40BisrD~6
return getHibernateTemplate().find #*/h*GNMs
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(query);
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} -tdG}Gu
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publicList find(finalString query, finalObject M[{:o/]<
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parameter){ }"Cn kg
return getHibernateTemplate().find U*TN/6Qy.
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(query, parameter); (c2\:hvy
} cFvx*n
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public PaginationSupport findPageByCriteria oUSG`g^P(M
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(final DetachedCriteria detachedCriteria){ m5X=P5U
return findPageByCriteria ]Dg0@Y
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); 9 a%@j
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} uyj*v]AE'
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public PaginationSupport findPageByCriteria '4sD1LD~}
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(final DetachedCriteria detachedCriteria, finalint [#Vr)\n
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startIndex){ =[+&({
return findPageByCriteria R
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(detachedCriteria, PaginationSupport.PAGESIZE, @#c6\$
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startIndex); n0pe7/Ai
} h';v'"DoW`
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public PaginationSupport findPageByCriteria
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(final DetachedCriteria detachedCriteria, finalint ^)l@7XxD
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pageSize, _|:bac8pL
finalint startIndex){ F@bCm+z-
return(PaginationSupport) wR4u}gb#q
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getHibernateTemplate().execute(new HibernateCallback(){ RgA4@J#
publicObject doInHibernate {Y%=/ba W
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(Session session)throws HibernateException { _Pi:TxY
Criteria criteria = _
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detachedCriteria.getExecutableCriteria(session); $ _Bu,;
int totalCount = 1/+r?F3
WCT W#<izm
((Integer) criteria.setProjection(Projections.rowCount -xIhN?r)
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()).uniqueResult()).intValue(); x>"JWD
criteria.setProjection ]u ~Fn2
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(null); v^_]W3K
List items = S_VncTIO
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criteria.setFirstResult(startIndex).setMaxResults T8TsKjqOZ
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(pageSize).list(); 6 Ok=q:;
PaginationSupport ps = V?dK *8s
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new PaginationSupport(items, totalCount, pageSize, L9?/ -@M
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startIndex); A<CXd t+t
return ps; )K%O/H
} C{i;spc!bi
}, true); Is6 _
} T1!Gr!=
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public List findAllByCriteria(final 8Pr7aT:,
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DetachedCriteria detachedCriteria){ 53*, f
return(List) getHibernateTemplate ~G:2iSi(#
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().execute(new HibernateCallback(){ N?{1'=Om
publicObject doInHibernate :`^3MMLO
! }?jCp p
(Session session)throws HibernateException { xP6?e s`
Criteria criteria = o"}&qA;
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detachedCriteria.getExecutableCriteria(session); {AL9o2
return criteria.list(); HGQ?(2] 8$
} j484b2uj1
}, true); ;zE5(3x
} V52C,]qQH
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public int getCountByCriteria(final [H:GKhPC`
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DetachedCriteria detachedCriteria){ 46P6Bwobh
Integer count = (Integer) i|]Va44
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getHibernateTemplate().execute(new HibernateCallback(){ [aM'
publicObject doInHibernate Xz.Y-5)
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(Session session)throws HibernateException { fxoi<!|iGY
Criteria criteria = }B9~X
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detachedCriteria.getExecutableCriteria(session); jy(+
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return ,WB_C\.#XN
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criteria.setProjection(Projections.rowCount %w8GGm8^/
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()).uniqueResult(); @6
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} ZAX0n!db3
}, true); ){
return count.intValue(); 8lWH=kA\
} 7.e7Fi{
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用户在web层构造查询条件detachedCriteria,和可选的 K4k~r!&OU
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 R{)
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PaginationSupport的实例ps。 2T@L{ ql
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ps.getItems()得到已分页好的结果集 {+"g':><
ps.getIndexes()得到分页索引的数组 n|x$vgb
ps.getTotalCount()得到总结果数 Y8%0;!T
ps.getStartIndex()当前分页索引 ^.D}k
ps.getNextIndex()下一页索引 ^}o7*
ps.getPreviousIndex()上一页索引 p"[O#*p
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 Xb]=:x(
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,尤其是上面的示例代码,让我着实觉得该对我原来的分页查询做 BrJ
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一下代码重构了。 [IX*sr
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我把原本我的做法也提供出来供大家讨论吧: 6ORY`Pe7P|
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首先,为了实现分页查询,我封装了一个Page类: g.x=pt
java代码: P_p6GT:5
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/*Created on 2005-4-14*/ W.A1m4l58R
package org.flyware.util.page; l80bHp=
r^$\t0h(U8
/** YC]PN5[1!
* @author Joa i`prv&
* }B y)y;~
*/ dG&2,n'f
publicclass Page { %
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/** imply if the page has previous page */ J &!B|TS
privateboolean hasPrePage; rdO@X9z
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/** imply if the page has next page */ Wk@
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privateboolean hasNextPage; GDF{Lf)/v
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/** the number of every page */ : *ERRSL)
privateint everyPage; *^'wFbaBO
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/** the total page number */ P:
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privateint totalPage; ?>sQF4 V"
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/** the number of current page */ #c-b}.R
privateint currentPage; #wF1
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/** the begin index of the records by the current 2s 7mI'
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query */ tWm> j
privateint beginIndex; OR]T`meO
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/** The default constructor */ qNpu}\L
public Page(){ Q:mZ" i5
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} 8Jr1_a
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/** construct the page by everyPage 0 h22V$
* @param everyPage c<?[d!vI
* */ NCi>S%pD`<
public Page(int everyPage){ \^LWCp,C"
this.everyPage = everyPage; iNQ0p:<k
} &pM'$}T*
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/** The whole constructor */ "A;s56 }'&
public Page(boolean hasPrePage, boolean hasNextPage, j eq:
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int everyPage, int totalPage, l4KbTKm7
int currentPage, int beginIndex){ Gg|M+M?+
this.hasPrePage = hasPrePage; &1_U1
this.hasNextPage = hasNextPage; }p=g*Zo*C;
this.everyPage = everyPage; Y9u;H^^G
this.totalPage = totalPage; =h|wwQE
this.currentPage = currentPage; D{cZxI
this.beginIndex = beginIndex; ^;r+W-MQ
} 0z7L+2#b^
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/** ]9*;;4Mg
* @return Ql &0O27
* Returns the beginIndex. DL {R|3{N
*/ h*3{6X#(/
publicint getBeginIndex(){ _ij$f<
return beginIndex; UQI
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} ;wR 'z$8
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/** "Z T.k5Z
* @param beginIndex ~zF2`.
* The beginIndex to set. s]H^wrg&
*/ #r<?v
publicvoid setBeginIndex(int beginIndex){ f8'MP9Lv
this.beginIndex = beginIndex; iY~rne"l
} *V1J4 u
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/** ZCYS\E7X
* @return C!&y
* Returns the currentPage. 4Po)xo
*/ ^aF8wbuZ
publicint getCurrentPage(){ #? ?%B
return currentPage; |cDszoT
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} v+=k-;-
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/** C5@V/vA
* @param currentPage *hdC?m._
* The currentPage to set. y&oNv
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*/ y3eHF^K+$
publicvoid setCurrentPage(int currentPage){ a{'Z5ail
this.currentPage = currentPage; g=l:cVr8y
} o>?*X(+le
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/** yGj.)$1},@
* @return ;%!B[+ut"
* Returns the everyPage. wX,F`e3"/
*/ / nZ;v4
publicint getEveryPage(){ @Uo6>-WF
return everyPage; MCc$TttaVz
} ,v9f~qh
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/** bAwl:l\`
* @param everyPage =f1B,%7G+5
* The everyPage to set. z[EFQ^*>
*/ ycAKK?O*
publicvoid setEveryPage(int everyPage){ 6l\FIah@
this.everyPage = everyPage; ]zfG~^.
} JC#>Td
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/** |=dC
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* @return )G1P^WV4
* Returns the hasNextPage. T=Z.TG|lIx
*/ mXzrEI
publicboolean getHasNextPage(){ :6{`~=
return hasNextPage; 9QC.TG@
} fJAnKUF)
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/** %^]?5a!
* @param hasNextPage %9v@0}5V
* The hasNextPage to set. ciQZHH2
*/ wzCUZ1N9q
publicvoid setHasNextPage(boolean hasNextPage){ h"+ `13
this.hasNextPage = hasNextPage; U/l?>lOD\
} ,u9M<B<F
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/** g\SrO {*
* @return M~Ttb29{
* Returns the hasPrePage. WjSc/3Qy
*/ _aWl]I){5
publicboolean getHasPrePage(){ R(Kk{c:-@
return hasPrePage; eYX5(`c[
}
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aGZi9O7G}
/** 8;14Q7,S
* @param hasPrePage @%ip7Y]e
* The hasPrePage to set. 7nq3S
*/ 1BHG'y
publicvoid setHasPrePage(boolean hasPrePage){ ao_4m SB
this.hasPrePage = hasPrePage; \b=Pj!^gwb
} X1{[}!
#|GSQJ$F)`
/** \%Ves@hG>
* @return Returns the totalPage. C)'q
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* u c7Eq45
*/ z!;1i[|x
publicint getTotalPage(){ ~Nf})U
return totalPage; 'y]\-T
}
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/** W14F
* @param totalPage )a@k]#)Skm
* The totalPage to set. c;0Vs,DUmG
*/ <JMcIV837
publicvoid setTotalPage(int totalPage){ :cu#V
this.totalPage = totalPage; ;9o;r)9~
}
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上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 bVP"(H]
n
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个PageUtil,负责对Page对象进行构造: ;%tF58&
java代码: !EUan
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/*Created on 2005-4-14*/ f&v9Q97=
package org.flyware.util.page; ]smkTo/
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import org.apache.commons.logging.Log; 2 41*!
import org.apache.commons.logging.LogFactory; {uzf"%VtP
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/** p<=$&*
* @author Joa PkI:*\R
* quY:pqG38q
*/ McB[|PmC
publicclass PageUtil { N F)~W#
;a:[8 Yi
privatestaticfinal Log logger = LogFactory.getLog RKPO#qju\F
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(PageUtil.class); .\>v0Du
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/** pz"0J_xDM
* Use the origin page to create a new page $D G?M6
* @param page f^W;A"+
* @param totalRecords E>l~-PaZY
* @return bhniB@<
*/ 5\z`-)
publicstatic Page createPage(Page page, int 1GzAG;UUo6
-Uml_/rd_
totalRecords){ m *JaXa
return createPage(page.getEveryPage(), 21"1NJzP
c/sC&i;%O
page.getCurrentPage(), totalRecords); X&kp;W
} Jv^h\~*jH
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/** KCs[/]
* the basic page utils not including exception 4:FK;~wM&x
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handler !r<pmr3f@7
* @param everyPage s0vDHkf8
* @param currentPage Yw-G'
* @param totalRecords {;2PL^i
* @return page WPQ fhr#|
*/ >7 ="8
publicstatic Page createPage(int everyPage, int 5 sX+~Q
wRVUu)
currentPage, int totalRecords){ |:gf lseE
everyPage = getEveryPage(everyPage); vX.VfY
currentPage = getCurrentPage(currentPage); 1jcouD5?H
int beginIndex = getBeginIndex(everyPage, 7<*yS310
^~etm
currentPage); j:v@pzTD
int totalPage = getTotalPage(everyPage, K|epPGRr
`x*Pof!Io
totalRecords); ?{ryGhb ~
boolean hasNextPage = hasNextPage(currentPage, \2h!aRWR
iUN Ib
totalPage); %$.3V#?
boolean hasPrePage = hasPrePage(currentPage); lgk.CC
.:F%_dS D
returnnew Page(hasPrePage, hasNextPage, 9P+-#B
everyPage, totalPage, @J/K-.r
currentPage, cPlZXf
?Wlb3;
beginIndex); 8)_XJ"9)G
} A
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privatestaticint getEveryPage(int everyPage){ ``hf=`We
return everyPage == 0 ? 10 : everyPage; )
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} asppRL||
Hx?;fl'G%
privatestaticint getCurrentPage(int currentPage){ pOIJH =#
return currentPage == 0 ? 1 : currentPage; ,s"^kFl
} s;ls qQk
0Qf,@^zL*
privatestaticint getBeginIndex(int everyPage, int u 7>],<
yPb" V
currentPage){ n-tgX?1'
return(currentPage - 1) * everyPage; AP 2_MV4W
} *XIF)Q=<>
+nFu|qM}
privatestaticint getTotalPage(int everyPage, int fHx*e'eA
n{argI8wF
totalRecords){ %]}
int totalPage = 0; Rl?_^dPx
_@
qjV~%Sy
if(totalRecords % everyPage == 0) \@c,3
totalPage = totalRecords / everyPage; Yg||{
else n FHUy9q
totalPage = totalRecords / everyPage + 1 ; UGV+/zxIM
K0|FY=#2y
return totalPage; TrEu'yxy8*
} RbOUfD(J4
(c=6yV@
privatestaticboolean hasPrePage(int currentPage){ u}macKJmp\
return currentPage == 1 ? false : true; Nk?
^1n$
} ?]_$Dcmx
"jKY1*?
privatestaticboolean hasNextPage(int currentPage, B"1c
BYL)nCc
int totalPage){ /[
5gX^A
return currentPage == totalPage || totalPage == wDal5GJp
P~ >OS5^
0 ? false : true; nv|NQ
Tk
} {HltvO%8
:^6y7&o[
KOk4^#h@
} -P$PAg5"2
$]/{[@5
%S960
uP)'FI
/|6N*>l)y
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 ;#W2|'HD
vxBgGl
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 y4?0j:
X:"i4i[}{9
做法如下: l` lk-nb
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 =
SMXDaH
]nn98y+
的信息,和一个结果集List: -V77C^()8d
java代码: ,aZ[R27rpL
zZPO&akB"
Y.(PiuG$G
/*Created on 2005-6-13*/ _aSxc)?
package com.adt.bo; nfbR
P t
*aM=Z+
import java.util.List; TQF| a\M'
hn
GZ=
import org.flyware.util.page.Page; "<N*"euH
gh]cXuph
/** {UI+$/v#
* @author Joa y'.p&QH'`
*/ Qz1E 2yJ
publicclass Result { Q~
w|#
YoNDf39
private Page page; -$ls(oot
(=AWOU+
private List content; ,?%Zc$\LW
>1Ibc=}g
/** *Hn8)x}E
* The default constructor (mpNcOY<D
*/ $bR~+C
public Result(){ p?OoC
super(); P/eeC"
} 97*p+T<yp
Ynj,pl
/** A}9`S6 @@
* The constructor using fields .uZ3odMlx
* 6<QQ@5_
* @param page JX;G<lev
* @param content WSB0~+
*/ `*R:gE=
public Result(Page page, List content){ .*Y
this.page = page; U%QI
a TN*
this.content = content; T.BW H2gRP
} 45c$nuZ
6A-|[(NS
/** +I|vzz`ZVr
* @return Returns the content. EV%gF
*/ \ ~$#1D1f
publicList getContent(){ [RhO$c$[\
return content; eq;uO6[
} f.$af4
u
Wd:uV
/** 1>h]{%I
* @return Returns the page. @qAS*3j
*/ JPw.8|V)y
public Page getPage(){ sDlO#
return page; p_%Rt"!
} pl?`8@dI
VpDbHAg
/** \_f(M|
* @param content '\iCP1>+S
* The content to set. HIZe0%WPw
*/ eD6fpe\(
public void setContent(List content){ 2E'UZ
m
this.content = content; >|UOz&
} W/h[A3 `3N
BRiE&GzrF
/** lt8|9"9<
* @param page *z8\Lnv~k
* The page to set. -uf|w?
*/ @\#td5'
publicvoid setPage(Page page){
_w+Qy.
this.page = page; H G^'I+Yn
} [{,1=AB
} m9rp8r*e
0 @oJFJrO
q(84+{>B
4^:=xL
( a#BV}=
2. 编写业务逻辑接口,并实现它(UserManager, Sdryol<
k9L;!TH~1K
UserManagerImpl) /%^#8<=|U
java代码: <Q3c[ Y
>4CbwwMA
PEZ!n.'S
/*Created on 2005-7-15*/ A*BeR0(
package com.adt.service; "^GGac.
F:S}w
import net.sf.hibernate.HibernateException; +
{'.7#
LKDO2N
import org.flyware.util.page.Page; Zj'9rXhrM1
k!Y, 63V=
import com.adt.bo.Result; yJIscwF
{+>-7
9b
/** Iu=(qU
* @author Joa CU!Dhm/U
*/ tQ#n${a@f
publicinterface UserManager { #Gi$DMW
N8df8=.kw
public Result listUser(Page page)throws fp"W[S|uL
?}Y]|c^W
HibernateException; G' 1'/
cH2K )~
} 1< ?4\?j
=?8@#]G+
8 LCb+^
#GFr`o0$^
CAf6:^0
java代码: ))Za&S*<
Kc\fu3Q
{oL>1h,%3?
/*Created on 2005-7-15*/ |Y.?_lC
package com.adt.service.impl; %(Icz?
'Pbr
v
import java.util.List; BnY&f
x4O~q0>:Le
import net.sf.hibernate.HibernateException; m]&SN z=
"<gOzXpa
import org.flyware.util.page.Page; K(|}dl:
import org.flyware.util.page.PageUtil; 4skD(au8
.6J$,.Ig
import com.adt.bo.Result; x?<FJ"8"k
import com.adt.dao.UserDAO; %"-5 <6d
import com.adt.exception.ObjectNotFoundException; N$tGQ@
import com.adt.service.UserManager; ;9#KeA _
-G=]=f/'
/** w32y3~
* @author Joa q,%st~
*/ y1#1Ne_
publicclass UserManagerImpl implements UserManager { glw+l'@
q.}CU.dp
private UserDAO userDAO; w!XD/jN
)U#K
/** @(lh%@hO
* @param userDAO The userDAO to set. }-`4DHgq
*/ _u Il
publicvoid setUserDAO(UserDAO userDAO){ 'c~4+o4co
this.userDAO = userDAO; pK4)yu+
} eJX#@`K
Alq(QDs
/* (non-Javadoc) %}T6]S)%u
* @see com.adt.service.UserManager#listUser Xwtqi@zlE
GN>@ZdVG}#
(org.flyware.util.page.Page) w2'5#`m
*/ oL<St$1
public Result listUser(Page page)throws }GIt!PG
7-A2_!_x{
HibernateException, ObjectNotFoundException { e:W{OIz:
int totalRecords = userDAO.getUserCount(); 6w7 7YTJ
if(totalRecords == 0) q cno^8R
throw new ObjectNotFoundException >-c8q]()ly
6H|S;K+
("userNotExist"); Mb=" Te>|
page = PageUtil.createPage(page, totalRecords); A %-6`>
List users = userDAO.getUserByPage(page); M3Kfd
returnnew Result(page, users); &m vSiyKX
} WEpoBP
CL
IGN1gs
} PI<vxjOK`
!!y a
3uMy]HUQ
c[e}w+uB
-{A<.a3P}=
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 {>;R?TG]$
H)&R=s
询,接下来编写UserDAO的代码: %>s|j'{
3. UserDAO 和 UserDAOImpl: {XHh8_^&
java代码: ^C%<l(b
S[QrS7
xLn%hxm?,
/*Created on 2005-7-15*/ YbLW/E\T
package com.adt.dao; 2+O'9F_v
-^wl>}#*T3
import java.util.List; :H[6Lg\*
.8|X
import org.flyware.util.page.Page; ]R? 4{t4
CH/rp4NeSy
import net.sf.hibernate.HibernateException; lRdChoL$2
aN=B]{!
/** F<w/PMb
* @author Joa jq-_4}w?C
*/ bN88ua}k{
publicinterface UserDAO extends BaseDAO { h.fq,em+H
{ "E\Jcjl\
publicList getUserByName(String name)throws cGD(.=
Vq2$'lY
HibernateException; c:g'.'/*
u-C)v*#L
publicint getUserCount()throws HibernateException; fn!KQ`,#
Xry47a
)
publicList getUserByPage(Page page)throws .[ mRM
V1JIht>Opo
HibernateException; ]s748+
}d }lR
} b u"!jHPB
D
sWSGb
m4yL@d,Yw
bJ;'`sw1
{zFMmPid
java代码: MJrR[h]
yCX?!E;La
3yXY.>'
/*Created on 2005-7-15*/ <Ok3FE.K
package com.adt.dao.impl; +'w3 =2Bo
2Wb]4-
import java.util.List; V470C@
I`p;F!s
import org.flyware.util.page.Page; )F2OT<]m,
E+JqWR5
import net.sf.hibernate.HibernateException; NgCvVWto
import net.sf.hibernate.Query; &!
?eL
!v0LBe4
import com.adt.dao.UserDAO; .6'qoo_N
&8 x-o,
/** \'bzt"f$j
* @author Joa r>U@3%0&
*/ O1mKe%'|
public class UserDAOImpl extends BaseDAOHibernateImpl ""|Qtubv
*=c1do%F
implements UserDAO { @|%2f@h
IB7E}56l
/* (non-Javadoc) ^v`\x5"Vp
* @see com.adt.dao.UserDAO#getUserByName C73kJa
<A'$%`6m
(java.lang.String) k)Qtfj}uij
*/ ^ovR7+V
publicList getUserByName(String name)throws ][h}
Z/;aT -N
HibernateException { (*)hD(C5
String querySentence = "FROM user in class 5o8EC"
0
{,~3.5u
com.adt.po.User WHERE user.name=:name"; q%?in+l
Query query = getSession().createQuery FG*r'tC~r
/RC7"QzL
(querySentence); eHDN\QA 2
query.setParameter("name", name); $H>W|9Kg,
return query.list(); Tyf`j,=
} nQ,HMXj
'y3!fN=h
/* (non-Javadoc) :A'y+MnK<
* @see com.adt.dao.UserDAO#getUserCount() )/?$3h;
*/ b`O'1r\Y;
publicint getUserCount()throws HibernateException { M1iS(x
int count = 0; "~C,bk
String querySentence = "SELECT count(*) FROM ~1vDV>dpE
*itUWpNhr
user in class com.adt.po.User"; u($!z^h
Query query = getSession().createQuery _8_R 1s
wT8DSq
(querySentence); g~A`N=r;h
count = ((Integer)query.iterate().next @wNG{Stj
h|{]B,.Lh
()).intValue(); I75DUJqy]
return count; )C]gld;8
} \ Et3|Iv
=w
2**$
/* (non-Javadoc) $6iX
* @see com.adt.dao.UserDAO#getUserByPage 6.nCV0xA
FZslv"F
(org.flyware.util.page.Page) 8i#2d1O
*/ !\.pq 2
publicList getUserByPage(Page page)throws XBu"-(
G^4hd i3@
HibernateException { iN8zo:&Z
String querySentence = "FROM user in class C
mWgcw1
"8jf81V*
com.adt.po.User"; CSq4x5!_7>
Query query = getSession().createQuery O so#+
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(querySentence); N.{H,oO `
query.setFirstResult(page.getBeginIndex()) Ata:^qI
.setMaxResults(page.getEveryPage()); +V046goX W
return query.list(); ZyPVy
} k],Q9
Q%tXQP .r
} 0e ~JMUb
""F5z,'
r8rgY42
'3DXPR^B6
T9_RBy;%
至此,一个完整的分页程序完成。前台的只需要调用 xvl#w
q" sed]
userManager.listUser(page)即可得到一个Page对象和结果集对象 O#~yKqB
dkBIx$t
的综合体,而传入的参数page对象则可以由前台传入,如果用 J^5So
zC@o
webwork,甚至可以直接在配置文件中指定。 &LZn
FR
`WFw3TI
下面给出一个webwork调用示例: dx{bB%?Y\=
java代码: J76kkW`5
# 0Q]dO
~{B7 k:
/*Created on 2005-6-17*/ @oY~..d`
package com.adt.action.user; j94=hJVKi
Eog0TQ+*
import java.util.List; +LZLy9iKt
z] PSpUd
import org.apache.commons.logging.Log; Yi+wC}
import org.apache.commons.logging.LogFactory; (\hx` Yh=>
import org.flyware.util.page.Page; #crQ1p) \
=9["+;\e&
import com.adt.bo.Result; xH(lm2kvT
import com.adt.service.UserService; ukfQe }I
import com.opensymphony.xwork.Action; Cc' 37~6~P
i6tf2oqO7
/** )c83/= <v
* @author Joa kmsb hYM)
*/ iWB=sL&p
publicclass ListUser implementsAction{ }{qZ[/JwqN
6YLj^w] %
privatestaticfinal Log logger = LogFactory.getLog gk[aM~p
]&xk30
(ListUser.class); EQyC1j
w\}ieI8J
private UserService userService; '}JhzKNj
~u!|qM
private Page page; }Jve cRtg1
H*QIB_
privateList users; ^aMg/.j
}QcCS2)Ud
/* gA5/,wDO
* (non-Javadoc) EXwo,?I
*
(GuzN
* @see com.opensymphony.xwork.Action#execute() f/NH:1)y
*/ {3p4:*}
publicString execute()throwsException{ 6C^
D#.S
Result result = userService.listUser(page); z8~NZ;A
page = result.getPage(); `* ["UER
users = result.getContent(); =wHVsdNCN
return SUCCESS; NP#w+Qw
} RtP2]O(F
V _/%b)*
/** wj<6kG
* @return Returns the page. Xe'x[(l
*/ y$F'(b|)
public Page getPage(){ }6}l7x
return page; 88gM?G _X
} p8H'{f\G
k>Vci{v
/** v
~?qz5:K~
* @return Returns the users. ;Ax
}KN7
*/ fZzoAzfv2
publicList getUsers(){ eKLZt%=
return users; +z\^t_"f
} 2K6qY)/_
+nhLIO{{L
/** 4 Y9`IgQ
* @param page E *6Cw
l
* The page to set. UWJ8amA
*/ V-2(?auZd
publicvoid setPage(Page page){ Rz:]\jcIT/
this.page = page; ,~$p,ALwN7
} VUGmi]qd
6|%?te x
/** LTCb@L{^i
* @param users "]x'PI 4J
* The users to set. @#>rYAb8,
*/ oUr66a/[U
publicvoid setUsers(List users){ v2\FA(BPn
this.users = users; J T7nG.9
} ")5":V~fN
9C9oUtS
/** (k)v!O-
* @param userService 7\[@m3s
* The userService to set. VG#EdIiI
*/ EIAc@$4
publicvoid setUserService(UserService userService){ ]t,BMu=%
this.userService = userService; HTS0s\R$
} P [ck84F/
} b<ZIWfs
OU.6bmWy|
Tc:)-
z[o
RFc v^Xf
c )g\/
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, 'n]w"]|
\fdv]f
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 6]N;r5n
M `M5'f
么只需要: $G+@_'
java代码: GPudaF{
P=Jo+4O
<w9JRpFY
<?xml version="1.0"?> B{#I:Rs9
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork vWv"
iByf{ I>+
1.0//EN" "http://www.opensymphony.com/xwork/xwork- k5e;fA/w
{9pZ)tB
1.0.dtd"> #L;dI@7C
=R|HV;9 h
<xwork> 3M7/?TMw{6
WDD%Q8ejV&
<package name="user" extends="webwork- mdDOvm:&
AKfDXy
interceptors"> @n /nH?L
tw/dD +
<!-- The default interceptor stack name #q$HQ&k
6;d*r$0Fc
--> lgy<?LI\
<default-interceptor-ref `HSKQ52
%)1?TU
name="myDefaultWebStack"/> AeM^73t
|aS.a&vwR
<action name="listUser" B dfwa
Bm<`n;m
class="com.adt.action.user.ListUser"> -d/
=5yxL
<param s!zx}
5
|syR6(U}
name="page.everyPage">10</param> L`TLgH&?R
<result l|[N42+
)2o?#8J
name="success">/user/user_list.jsp</result> V2EUW!gn
2
</action> z&\a:fJ&
SKN`2[ahD
</package> _;y9$"A
ebhXak[w
</xwork> Ll't>)
2l'6.
*N<]Xy@
K5h
|wMN}bq|T
(%6P0*
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 'H>^2C iM
RtS+<^2a;
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。 2F.;;Ab
<'oQ \eB
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 ]%H`_8<gc
hn@08t G
B9z?mt'|r)
!e<^?
r4
7n<{tM
我写的一个用于分页的类,用了泛型了,hoho YD6'#(
Zu[su>\
java代码: ~<bZ1TD
v\ )W?i*l
4+8@`f>s
package com.intokr.util; [z{1*Xc
Wac&b
import java.util.List; _B<X`L
=
wP@(?z
/** vk^xT
* 用于分页的类<br> _G@GpkSe>
* 可以用于传递查询的结果也可以用于传送查询的参数<br> lL3U8}vn
* <]2w n
* @version 0.01 d$!RZHo10V
* @author cheng u6JM]kR
*/ 7?_CcRe
public class Paginator<E> { #X1ND
privateint count = 0; // 总记录数 m-, x<bM?
privateint p = 1; // 页编号 WOap+
privateint num = 20; // 每页的记录数 gM:".Ee
privateList<E> results = null; // 结果 4!?eRY
F JyT+
/** sO@Tf\d
* 结果总数 Q;rX;p^W
*/ ~]2K^bh8&
publicint getCount(){ f-Z/tfC
return count; x%B/
} R\[e!g*I
[4f{w%~^
publicvoid setCount(int count){ &^jXEz;
this.count = count; > ~O.@|
}
x.$FNt(9
NzvXN1_%
/** @q)d
* 本结果所在的页码,从1开始
P*j|.63
* OneY_<*a<
* @return Returns the pageNo. |sE'XT4ag
*/ T>W,'H
publicint getP(){ +NUG
return p; "w<#^d_6
} (tW`=]z-<
Z%UP6%
/** 4Z0]oIX
* if(p<=0) p=1 y6BAH
* `R^g U]Z,
* @param p Q7CsJzk~)
*/ ?S=mybp
publicvoid setP(int p){ N;%6:I./
if(p <= 0) q)
KKvO
p = 1;
]ZS
OM\}
this.p = p; 8&dF
} ]Hv[ IodJ
0"z9Q\{}
/** YS_;OFsd
* 每页记录数量 R4d=S4i
*/ l'E6CL}@[
publicint getNum(){ )+Pus~w
return num; tZo} ;|~'
} W2!+z{:m
>yDZw!C
/** Ax}JLPz5'
* if(num<1) num=1 <~=Vg
*/ dAj$1Ke
publicvoid setNum(int num){ /Z4et'Lo
if(num < 1) HxI"
8A
num = 1; sDV Q#}a
this.num = num; }<:}XlwT%
} w4Z'K&