Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 UE8kpa)cQ
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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 OSRp0G20k\
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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 hCi 60%g/n
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分页支持类: "Bh}}!13
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java代码: 8V~k5#&Ow
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package com.javaeye.common.util; $jjfC
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import java.util.List; W/=.@JjI
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publicclass PaginationSupport { =rMUov h
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publicfinalstaticint PAGESIZE = 30; r )Ma3FL0;
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privateint pageSize = PAGESIZE; Lz
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privateList items; R
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privateint totalCount; pI1-cV,`
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privateint[] indexes = newint[0]; )cX*I gO
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privateint startIndex = 0; Z&G+bdA>,
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public PaginationSupport(List items, int TtK[nP
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totalCount){ 8^kGS-+^
setPageSize(PAGESIZE); M-$%Rzl_
setTotalCount(totalCount); lXx=But
setItems(items); ^6jV_QM#
setStartIndex(0); ^4y,W]JUDt
} 6,^>mNm
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public PaginationSupport(List items, int l^!
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totalCount, int startIndex){ X@ --m6-
setPageSize(PAGESIZE); ^3G{|JB!+
setTotalCount(totalCount); eln)BW#
setItems(items); HSw;^E)1
setStartIndex(startIndex); 2% MC Yn
} im${3 >26
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public PaginationSupport(List items, int E`kG-Q5Dw
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totalCount, int pageSize, int startIndex){ aEBu *`-j
setPageSize(pageSize); DMAIM|h
setTotalCount(totalCount); T"(&b~m2b4
setItems(items); _no/F2>!/n
setStartIndex(startIndex); hnffz95
} TCMCK_SQL
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publicList getItems(){ TeMHm?1^
return items; <!&[4-;fU
} HNb/-e ,"
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publicvoid setItems(List items){ JL`-0P<M
this.items = items; z$&{:\hj
} aKJwofD
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publicint getPageSize(){ \J4L:.`qS
return pageSize; t DO=P
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} <h!_>:2L
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publicvoid setPageSize(int pageSize){ aJSO4W)P
this.pageSize = pageSize; cA&9e<
} L s
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publicint getTotalCount(){ rExnxQ<e
return totalCount; -fM1nH&
} b\ X@gq
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publicvoid setTotalCount(int totalCount){ @tF\p
if(totalCount > 0){ \|n-
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this.totalCount = totalCount; gGR"Z]DBk
int count = totalCount / *~2,/D
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pageSize; _Mi5g_
if(totalCount % pageSize > 0) 2kqu p)82e
count++; q'+)t7!
indexes = newint[count]; 7( #:GD
for(int i = 0; i < count; i++){ T*I{WW
indexes = pageSize * \Yy$MLs
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} Ah1]Y}sy
}else{ M
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this.totalCount = 0; hz{`h
} BfXgh'Z~
} K>
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publicint[] getIndexes(){ x!hh"x
return indexes; ZVW'>M7.
} pk>^?MO
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publicvoid setIndexes(int[] indexes){ Lk|hQ
this.indexes = indexes; !zBhbmlKt
} Plc-4y1
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publicint getStartIndex(){ Yh7rU?Gj
return startIndex; |O3q@
} 8aZ=?_gvT
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publicvoid setStartIndex(int startIndex){ 2v :]tj
if(totalCount <= 0) Pi=+/}
this.startIndex = 0; ;$HftG>B
elseif(startIndex >= totalCount) .28<tEf
this.startIndex = indexes Z~GL5]S
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[indexes.length - 1]; 1eA7>$w}[
elseif(startIndex < 0) QemyCCP+
this.startIndex = 0; fAF1"4f
else{ S2E8Gq9
this.startIndex = indexes GeI-\F7b
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[startIndex / pageSize]; _ "E$v&_
} {M3qLf~z#C
} S&e0u%8mc
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publicint getNextIndex(){ e4-@f%5
int nextIndex = getStartIndex() + 9X[kEl
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pageSize; GXcJ< v
if(nextIndex >= totalCount) eJ,/:=QQ{
return getStartIndex(); r=Gks=NX"
else "_P;2N6
return nextIndex; Y21g{$~Q{
} % BVs47g
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publicint getPreviousIndex(){
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int previousIndex = getStartIndex() - 4Xgg%@C
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pageSize; eP.wOl
if(previousIndex < 0) w2Us!<x
return0; &]V.S7LC#
else 7Sf
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return previousIndex; H[m:0eF'5
} uyO/55;HO
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} 'SO %)B
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抽象业务类 P|^f0Rw3.
java代码: 09|K>UC)v
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/** B3: ez
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* Created on 2005-7-12 ZLc -RM
*/ %}[i'rT>
package com.javaeye.common.business; A mvEf
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import java.io.Serializable; $>G8_q
import java.util.List; yZ
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import org.hibernate.Criteria; au N6prGe
import org.hibernate.HibernateException; ,bXe<L)
import org.hibernate.Session; }bs+-K
import org.hibernate.criterion.DetachedCriteria; .I$qCb|FP
import org.hibernate.criterion.Projections; kd>hhiz|
import j1^I+j)
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org.springframework.orm.hibernate3.HibernateCallback; VX].3=T8
import cIUHa
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org.springframework.orm.hibernate3.support.HibernateDaoS ? 8)'oMD
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upport; neB\q[k
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import com.javaeye.common.util.PaginationSupport; ;i8g41qjF
. kQkC:~9
public abstract class AbstractManager extends "76]u)
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HibernateDaoSupport { H6kR)~zhf
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privateboolean cacheQueries = false; ;}7Rjl#
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privateString queryCacheRegion; >x/z7v?^I
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publicvoid setCacheQueries(boolean wZG\>9~
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cacheQueries){ 3Q"<<pi!~
this.cacheQueries = cacheQueries; lun#^ J
} 1uG"f<TsR
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publicvoid setQueryCacheRegion(String ht7l- AK
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queryCacheRegion){ :X0k]p
this.queryCacheRegion = %WSo b@f8
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queryCacheRegion; mi
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} B,<da1(a
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publicvoid save(finalObject entity){ C^3 <={
getHibernateTemplate().save(entity); O#b6mKPt;t
} O|\J}rm'
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publicvoid persist(finalObject entity){ dUsYZdQs
getHibernateTemplate().save(entity); $()5VMb
} 9Kpa><
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publicvoid update(finalObject entity){ yQU_>_!n
getHibernateTemplate().update(entity); FO=4:
} mN~ci 0
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publicvoid delete(finalObject entity){ 34z"Pm
getHibernateTemplate().delete(entity); io _1Y]N
} -!q:p&c
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publicObject load(finalClass entity, GU4'&#
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finalSerializable id){ !5.8]v
return getHibernateTemplate().load XJ;D=~
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(entity, id); {K <iih
} jB`,u|FG
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publicObject get(finalClass entity, RzBF~2 >i
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finalSerializable id){ XDsx3Ws
return getHibernateTemplate().get esHg'8?U
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(entity, id); i8`Vv7LF
} nKS7Q1+
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publicList findAll(finalClass entity){ o1Ph~|s*8
return getHibernateTemplate().find("from e]`[yf
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" + entity.getName()); K17j$o^6KK
} , 0imiv
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publicList findByNamedQuery(finalString Y-pzy']4
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namedQuery){ UADFnwR[R
return getHibernateTemplate IT(lF
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().findByNamedQuery(namedQuery); #,,d>e
} [ad@*KFxy3
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publicList findByNamedQuery(finalString query, OTy.VT|
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finalObject parameter){ }x@2]juJ
return getHibernateTemplate u6T+Cg
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().findByNamedQuery(query, parameter); (}a8"]Z
} qLw{?sH}J/
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publicList findByNamedQuery(finalString query, gGr^@=;YC
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finalObject[] parameters){ 0TCBQ~ "
return getHibernateTemplate {aY%gk?y#>
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().findByNamedQuery(query, parameters);
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} ]+(6,ct&.
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publicList find(finalString query){ `!XY]PI+e
return getHibernateTemplate().find iJ~Zkd
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(query); G"\`r* O
} I Y2)?"A
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publicList find(finalString query, finalObject uv=.2U46
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parameter){ .Si,dc\
return getHibernateTemplate().find *FC=X) _&W
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(query, parameter); eCN })An
} =+ytTQc*ot
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public PaginationSupport findPageByCriteria N"8_S0=pw
#.it]Nv{
(final DetachedCriteria detachedCriteria){ ABF"~=aL
return findPageByCriteria ko Z
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); hJn%mdx~w|
} crqpV F]1]
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public PaginationSupport findPageByCriteria Qy.w=80kf
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(final DetachedCriteria detachedCriteria, finalint V^JV4 `o
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startIndex){ S'A>2>
return findPageByCriteria (5R?#vj
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(detachedCriteria, PaginationSupport.PAGESIZE, g6Q !8
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startIndex); :,Pn3xl
} y=`2\L" O
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public PaginationSupport findPageByCriteria &0NFb^8+
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(final DetachedCriteria detachedCriteria, finalint GqWB{$J;"
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pageSize, \]=7!RQ\
finalint startIndex){ kB/D!1
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return(PaginationSupport) ,=tD8@a<
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getHibernateTemplate().execute(new HibernateCallback(){ dik:4;
publicObject doInHibernate 4"{ooy^Q
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(Session session)throws HibernateException { 0o+6Q8q
Criteria criteria = y9_K, g
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detachedCriteria.getExecutableCriteria(session); D$bIo"
int totalCount = F_;vO%}
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((Integer) criteria.setProjection(Projections.rowCount -sw
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()).uniqueResult()).intValue(); Fe]B&n
criteria.setProjection x*?x=^I{
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(null); >+]_5qc
List items = wW#}:59}
)+}]+xRWGj
criteria.setFirstResult(startIndex).setMaxResults ROk5]b.
?\$#L^;b}
(pageSize).list(); XLAN Np%E
PaginationSupport ps = FP;Ccl"s
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new PaginationSupport(items, totalCount, pageSize, jJuW-(/4[
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startIndex); c8L~S/t
return ps; %7"X(Ts7B
} cJ1#ge%4
}, true); 31rx-D8o
} 3H|_mX
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public List findAllByCriteria(final 2'_:S@
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DetachedCriteria detachedCriteria){ Fb7#<h
return(List) getHibernateTemplate TQx.KM>y
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().execute(new HibernateCallback(){ o3I Tr';
publicObject doInHibernate fRtUvC-#H
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(Session session)throws HibernateException { 'h^0HE\~p
Criteria criteria = MxGu>r
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detachedCriteria.getExecutableCriteria(session); 9T|IvQK8
return criteria.list(); RA G3o-
} qQ"Fv|]~>
}, true); NR -!VJQ
} y($%;l
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public int getCountByCriteria(final q)Fq
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DetachedCriteria detachedCriteria){ SzUpWy&
Integer count = (Integer) oo=Qt(#
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getHibernateTemplate().execute(new HibernateCallback(){ /%&2HDA)
publicObject doInHibernate %n
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(Session session)throws HibernateException { yto,>Utzg
Criteria criteria = f}1&HI8r
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detachedCriteria.getExecutableCriteria(session); l-ct?T_@
return &_"]5/"(
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criteria.setProjection(Projections.rowCount B
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()).uniqueResult(); hir4ZO%Zt
} )('%R|$ /
}, true); Gm(b/qDDe
return count.intValue(); Kj<^zo%w
} 'ow.=1N-
} ?r?jl;A&
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用户在web层构造查询条件detachedCriteria,和可选的 #m[|2R
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 ,4ei2`wV
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PaginationSupport的实例ps。 L2, 1Kt7
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ps.getItems()得到已分页好的结果集 6IWxPt~
ps.getIndexes()得到分页索引的数组 {%IE xPJ
ps.getTotalCount()得到总结果数 e _/b2"{
ps.getStartIndex()当前分页索引 j{NNSi3
ps.getNextIndex()下一页索引 /Wy.>YC|
ps.getPreviousIndex()上一页索引 'Er:a?88l
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 2 Sh
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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 vP!{",>
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一下代码重构了。 J,zO2572u
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我把原本我的做法也提供出来供大家讨论吧: de>v
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首先,为了实现分页查询,我封装了一个Page类: kI:}| _
java代码: qQ0cJIISb\
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/*Created on 2005-4-14*/ Op>%?W8/UF
package org.flyware.util.page; *P#WDXRwd
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/** ^|TG$`M(w
* @author Joa xCYE
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* Gkp<o
*/ dlG=Vq&Y
publicclass Page { jS]><rm
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/** imply if the page has previous page */ ZKXo-~=>
privateboolean hasPrePage; !>>f(t4
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/** imply if the page has next page */ Dgx8\~(E'
privateboolean hasNextPage; J]q%gcM
8,atX+tc
/** the number of every page */ r" K':O6y
privateint everyPage; v*9<c{a
3 q`)*
/** the total page number */ SL,p36N
privateint totalPage; 2e|N@j
&
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/** the number of current page */ O)Y?=G)
privateint currentPage; gt/zpiKmV
;L,mBQB?0b
/** the begin index of the records by the current fPrLM'
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query */ Z*])6=2Q
privateint beginIndex; $DZHQH
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/** The default constructor */ **+e7k
public Page(){ BbRBT@
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} QMsHC%l3b
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/** construct the page by everyPage ]r-C1bKD`
* @param everyPage 11,!XD*"
* */ JkGnKm9G
public Page(int everyPage){ ;A'":vXmc
this.everyPage = everyPage; cW{1
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} iR\Hv'|
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/** The whole constructor */ HFq m6|
public Page(boolean hasPrePage, boolean hasNextPage, 4<x'ocKlD
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int everyPage, int totalPage, ru`U'
int currentPage, int beginIndex){ 9W8]8sUeG
this.hasPrePage = hasPrePage; /RyR>G!
this.hasNextPage = hasNextPage; ?h0X,fl3
this.everyPage = everyPage; $-&BB(-{E&
this.totalPage = totalPage; #_B-4sm
this.currentPage = currentPage; R@wjccu
this.beginIndex = beginIndex; sO5?aB&
} J-ePE7i
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/** T2D<UhP
* @return w ~ dk#=
* Returns the beginIndex. 93<:RV
*/ LPwT^zV&N
publicint getBeginIndex(){ {>"NyY
return beginIndex; n 3lE,b
} ?X-)J=XG
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/** :=9] c17=
* @param beginIndex }'OHE(s
* The beginIndex to set. fRfn2jA)d
*/ Y $u9%0q|?
publicvoid setBeginIndex(int beginIndex){ k6kM'e3V
this.beginIndex = beginIndex; ||zb6|7I4
} :iiw3#]
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/** jt@SZI`
* @return <F
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* Returns the currentPage. 0A:n0[V:]
*/ fGv#s
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publicint getCurrentPage(){ |8bq>01~
return currentPage; CdUAy|!`R
} N-g8}03
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/** '&99?s`u
* @param currentPage xcJ`1*1N
* The currentPage to set. QW_agm
*/ ^ZM0c>ev=l
publicvoid setCurrentPage(int currentPage){ 2S8P}$mM
this.currentPage = currentPage; O,<IGO
} O'GG Ti]e
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/** +f0~D(d!_
* @return +x]9+D&
* Returns the everyPage. azP+GM=i7
*/ >23-
publicint getEveryPage(){ /j"sS2$U
return everyPage; ^>?CMcN4*
} AkU<g
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/** j$da8] !
* @param everyPage QR">.k4QJ
* The everyPage to set. y{9~&r
*/ pr,p=4m{\
publicvoid setEveryPage(int everyPage){ $^ 'aCU0C
this.everyPage = everyPage; lZ&]|*>
} AOp/d(vx5i
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/** \#'TNmS
* @return qi^!GA'5j
* Returns the hasNextPage. #,(sAj
*/ q@hp.(V
publicboolean getHasNextPage(){ >O/D!j|
return hasNextPage; `d 2,*KR
} ki;UY~
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/** { m8+Wju}
* @param hasNextPage K={qU[_O
* The hasNextPage to set. ZAuWx@}
*/ qpJ{2Q
publicvoid setHasNextPage(boolean hasNextPage){ t!1$$e?`r
this.hasNextPage = hasNextPage; 7*w VI+
} rg_Q"g
}%TSGC4{
/** OndhLLz
* @return `N/RHb%
* Returns the hasPrePage. 6+K_ Z\
*/ ]=73-ywn]
publicboolean getHasPrePage(){ (x;g/!:
return hasPrePage; mgZf3?,)
} 1x~U*vbhQ
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/** jy2IZ o
* @param hasPrePage .7ayQp
* The hasPrePage to set. Fk=}iB#(
*/ Hqz?E@bc@
publicvoid setHasPrePage(boolean hasPrePage){ Wk4.%tpeO7
this.hasPrePage = hasPrePage; G+*cpn
} f DgD@YC D
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/** <uP^-bv;(
* @return Returns the totalPage. 5wC* ?>/
* ]>i~6!@
*/ jx_4B%kzq
publicint getTotalPage(){ jY!ZkQsVe
return totalPage; T:asm1BC[
} 1;eX&
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/** t>UkE9=3\
* @param totalPage tGcya0RL
* The totalPage to set. ! o,5h|\
*/ ]r]k-GZ$
publicvoid setTotalPage(int totalPage){ S\NL+V?7h
this.totalPage = totalPage; 2_QN&o ~h
} d6 _C"r
h7_)%U<J2
} K_-d(
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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 1D([@)^
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个PageUtil,负责对Page对象进行构造: &[|VZ[
java代码: }ublR&zlp
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/*Created on 2005-4-14*/ |E/L.gdP7
package org.flyware.util.page; 7_KhV
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import org.apache.commons.logging.Log; N1--~e
import org.apache.commons.logging.LogFactory; ES:!Vx9t0|
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/** GtI6[ :1t
* @author Joa
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* {6vEEU
*/ |@VF.)_
publicclass PageUtil { v$|mo;6
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privatestaticfinal Log logger = LogFactory.getLog MXAEX2xmme
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(PageUtil.class); 0??Yr
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/** EH9Hpo
* Use the origin page to create a new page ,qFA\cO*
* @param page ~0tdfK0c
* @param totalRecords yDd[e]zS`
* @return 8LM#WIm?
*/ !)OB@F%U
publicstatic Page createPage(Page page, int =LH}YUmd
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totalRecords){ 4B O %{
return createPage(page.getEveryPage(), @6xGJ,s
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page.getCurrentPage(), totalRecords); Zy]s`aa
} 0my9l;X
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/** {/M\Q@j
* the basic page utils not including exception 7|D|4!i2Y
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handler qJs[i>P[W
* @param everyPage p%RUHN3G[
* @param currentPage oFg'wAO.
* @param totalRecords ,r+"7$
* @return page Etnb3<^[t
*/ ?g}kb
publicstatic Page createPage(int everyPage, int >2-F2E,
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currentPage, int totalRecords){ CUhV$A#oo
everyPage = getEveryPage(everyPage); *=nO
currentPage = getCurrentPage(currentPage); 2*[Un(
int beginIndex = getBeginIndex(everyPage, @5Qoi~o
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currentPage); fNhT;Bux
int totalPage = getTotalPage(everyPage, c;V D}UD'
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totalRecords); 03E3cp"
boolean hasNextPage = hasNextPage(currentPage, C!UEXj`l9
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totalPage); QPg2Y<2
boolean hasPrePage = hasPrePage(currentPage); U~QMR-bz
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returnnew Page(hasPrePage, hasNextPage, 5d
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everyPage, totalPage, =:5<{J OG
currentPage, a&5g!;.
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beginIndex); h(:<(o@<
} VO9f~>`(
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privatestaticint getEveryPage(int everyPage){ g,?\~8-c
return everyPage == 0 ? 10 : everyPage; !k h{9I>M
} $N\+,?
q+/l"&j.
privatestaticint getCurrentPage(int currentPage){ BjD&>gO)
return currentPage == 0 ? 1 : currentPage;
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} ER<eX4oU
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privatestaticint getBeginIndex(int everyPage, int rt.[,m
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currentPage){ syFI$rf
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return(currentPage - 1) * everyPage; )fCMITq.|
} <9 },M
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privatestaticint getTotalPage(int everyPage, int SI_?~Pf3k
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totalRecords){ V4?Oc2mS
int totalPage = 0; hZF(/4Z2
,kE=TR.|
if(totalRecords % everyPage == 0) |Y{PO&-?r
totalPage = totalRecords / everyPage; B! `\L!
else 3/tJDb5
totalPage = totalRecords / everyPage + 1 ; q!2<=:f
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return totalPage; u%aFb*
} M71R -B`-
.;Z.F7{q
privatestaticboolean hasPrePage(int currentPage){ 5&%fkZ0
return currentPage == 1 ? false : true; j];G*-iv{
} Kw*~W
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privatestaticboolean hasNextPage(int currentPage, V85.DK!
yM17H\ =
int totalPage){ C38XQLC
return currentPage == totalPage || totalPage == `(T!>QVW+g
4
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0 ? false : true; YAMfP8S
} u9@b<
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} FG _,
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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。
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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 mrReast
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做法如下: C$ hQN
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 !3?~#e{_
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的信息,和一个结果集List: R}.3|0
java代码: 1O9$W?)Q
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j #es2;
/*Created on 2005-6-13*/ #rq?f
package com.adt.bo; Y`=z.D{
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import java.util.List; x {vIT- f
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import org.flyware.util.page.Page; /[L)tj7B
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/** `
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* @author Joa hJ4S3b
*/ r?]%d!
publicclass Result { #O><A&FrF`
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private Page page; cyHhy_~R
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private List content; 7>KQRLw
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/** tUrNp~ve,
* The default constructor )ZeLaa P
*/ 79a9L{gso
public Result(){ n8Q*
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super(); p*!q}%U
} >Ban?3{
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/** T&!ZD2I
* The constructor using fields M.t@@wq
* z2ds8-z
* @param page pbFYiu+
* @param content e-jw^
*/ " C&x,Ic
public Result(Page page, List content){ wU.'_SBfB
this.page = page; xLZMpP5c
this.content = content; @,GjeF]!
} .2/,XwIr
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/** WySNL#>a
* @return Returns the content. 4xp j<
*/ h9U+%=^O
publicList getContent(){ H[Cj7{V
return content; 3 ^pYCK%
} a&8l[xe1
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/** <TL])@da
* @return Returns the page. $>|?k$(x
*/ (%Ng'~J\|
public Page getPage(){ {GAsFnZk
return page; $>EqH?EQ
} \A ;^ UxG
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/** ZHb7+
* @param content F@Pem
* The content to set. R2SBhs,+R
*/ 4Sqvhz
public void setContent(List content){ ^z38<L=z"
this.content = content; zv`zsqDJ
} (2cGHYU3N<
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/** n}+wd9J*!2
* @param page ?-4OfGN
* The page to set. 2$iw/r
*/ QZ#3Bn%B5
publicvoid setPage(Page page){ :l4^iSf
this.page = page; ysL0hwir
} j-j'ph K
} ,!jR:nApE
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|G>q:]+AV
5s#R`o%Z
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2. 编写业务逻辑接口,并实现它(UserManager,
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UserManagerImpl) pb~Ps#"Zg
java代码: Pkj T&e)
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5sG ]3z+1
/*Created on 2005-7-15*/ PpW
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package com.adt.service; RA!x
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import net.sf.hibernate.HibernateException; D`1I;Tb#
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import org.flyware.util.page.Page; FpwlV}:
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import com.adt.bo.Result; $_ST:h&C
" vv$%^
/** B8`R(vu;
* @author Joa -Mr{+pf
*/ - $xKv4
publicinterface UserManager { D WsCYo
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public Result listUser(Page page)throws B9%yd*SJ
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HibernateException; 8''9@xz
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} ~3LhcU-
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P9 W<gIO
java代码: S~]8K8"sT
n P0Ziu'{
C~3@M<X
/*Created on 2005-7-15*/ a.5zdoH_
package com.adt.service.impl; b>GqNf!
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import java.util.List; I|Vk.,
N )b|
import net.sf.hibernate.HibernateException; at_dmU2[7
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import org.flyware.util.page.Page; XHU<4l:kl
import org.flyware.util.page.PageUtil; R^n*
o
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import com.adt.bo.Result; AT2NC6{M
import com.adt.dao.UserDAO; 8 /:X&
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import com.adt.exception.ObjectNotFoundException; mBYS"[S(
import com.adt.service.UserManager; {s9y@c*15.
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/** Dx9$H++6$X
* @author Joa | 7t=\
*/ )Mm;9UA
publicclass UserManagerImpl implements UserManager { w*|= k~z
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private UserDAO userDAO; n_e}>1_
,U} 5
/**
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* @param userDAO The userDAO to set. 3j[w
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*/ #n6FQ$l8m
publicvoid setUserDAO(UserDAO userDAO){ *y":@T
this.userDAO = userDAO; %[+a[/
} 4GmSG,]
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/* (non-Javadoc) s!nSE
* @see com.adt.service.UserManager#listUser N]O{T_5-0
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(org.flyware.util.page.Page) 0jip::x
*/ Q"l"p:n%n
public Result listUser(Page page)throws //`cwnjp
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HibernateException, ObjectNotFoundException {
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int totalRecords = userDAO.getUserCount(); $?CBX27AV
if(totalRecords == 0) Q]2sj:
throw new ObjectNotFoundException hi4h0\L!}
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("userNotExist"); 0|K/=dh5+
page = PageUtil.createPage(page, totalRecords); 4EaSg#
List users = userDAO.getUserByPage(page); .O@q5G
returnnew Result(page, users); {7ZtOe
} o|p;6
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} mTI\,x%<OC
$)kBz*C[
}
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其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 X*c_^g{
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询,接下来编写UserDAO的代码: 6x (L&>F
3. UserDAO 和 UserDAOImpl: buxI-wv
java代码: %O4}i@Fe
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/*Created on 2005-7-15*/ O[5_9W
4
package com.adt.dao; N c&i) qh
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import java.util.List; &?5{z\;1"
uZ=UBir
import org.flyware.util.page.Page; g~$GE},,
@FnI?Rx
import net.sf.hibernate.HibernateException; Ok~W@sYST
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/** :+?W
* @author Joa >TY5ZRB
*/ vS24;:f
publicinterface UserDAO extends BaseDAO { cA (e"N
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publicList getUserByName(String name)throws #<PA-
y
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HibernateException; 7KSGG1ts
n'&`9M['%d
publicint getUserCount()throws HibernateException; #)h
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publicList getUserByPage(Page page)throws 9qu24zz$P
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HibernateException; >`rNT|rg
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} A 4W
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java代码: >fZ/09&3
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wMPw/a;
/*Created on 2005-7-15*/ X\$W'^ np
package com.adt.dao.impl; ~b6<uRnM.
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import java.util.List; !$KhL.4P
7N59B z
import org.flyware.util.page.Page; dD.d?rnZq7
uZiY<(X
import net.sf.hibernate.HibernateException; gt t$O
import net.sf.hibernate.Query; w#G=Z_Tt
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import com.adt.dao.UserDAO; eDM0417O(
!qw=I(
/** ~q_+;W.
* @author Joa @y\{<X.F\1
*/ vo( j@+dz
public class UserDAOImpl extends BaseDAOHibernateImpl ?lwQne8/
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implements UserDAO { y'2kV6TtqD
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/* (non-Javadoc) vb"dX0)<
* @see com.adt.dao.UserDAO#getUserByName /4B4IT
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(java.lang.String) h3d\MYO)B
*/ 3Llj_lf
publicList getUserByName(String name)throws Zqs-I8y
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HibernateException { _9-D3_P[3
String querySentence = "FROM user in class =u3@ Dhw
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com.adt.po.User WHERE user.name=:name"; 3Gd&=IJ
Query query = getSession().createQuery ^3)2]>pW
(~pEro]?+)
(querySentence); ~~:8Yv[(
query.setParameter("name", name); 97))'gC
return query.list(); ?.Yw%{?TG
} ;`PkmAg
PSQ:'
/* (non-Javadoc) `)C`_g3Ew
* @see com.adt.dao.UserDAO#getUserCount() CpqSn/
*/ $-9@ /%Y
publicint getUserCount()throws HibernateException { S.F=$z.%
int count = 0; `Ig2f$}
String querySentence = "SELECT count(*) FROM 5f*'wA
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user in class com.adt.po.User"; b;{"lJ:+Z
Query query = getSession().createQuery ?6YUb;
'iISbOM
(querySentence); *JC{G^|Y
count = ((Integer)query.iterate().next C.B}Py+
WKIiJ{@L
()).intValue(); .SV3<)
return count; X@AkA9'fq
} s^?sJUj
\y )4`A
/* (non-Javadoc) PLD'Q,R
* @see com.adt.dao.UserDAO#getUserByPage b}L,kT
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(org.flyware.util.page.Page) g&F<Uv#mZ
*/ A{Htpm ~
publicList getUserByPage(Page page)throws )>M@hIV5>
'-]BSU
HibernateException { [`-O-?=
String querySentence = "FROM user in class 8!%"/*P$
~W *j^+T"
com.adt.po.User"; &aAo:pj
Query query = getSession().createQuery -%V-'X5
U9fF;[g
(querySentence); ;$L!`"jn
query.setFirstResult(page.getBeginIndex()) 7C?mD75j
.setMaxResults(page.getEveryPage()); ODvpMt:+
return query.list(); jG(~9P7
} RGA*7
5m7Ax]\
} I nK)O';
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wYMX1=
jzA8f+:q
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至此,一个完整的分页程序完成。前台的只需要调用 wY_-
G{Enh<V
userManager.listUser(page)即可得到一个Page对象和结果集对象 DD$Pr&~=
27 TZ+?
的综合体,而传入的参数page对象则可以由前台传入,如果用 y^46z(I
RrpFi'R
webwork,甚至可以直接在配置文件中指定。 "sx&