Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 0 HPqoen$
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 LOi/+;>
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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 cxz\1Vphd
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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 [m0G;%KR/
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分页支持类: -jk-ve
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java代码: Ft<B[bQ
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package com.javaeye.common.util; LO@o`JF
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import java.util.List; 6<Txkk
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publicclass PaginationSupport { A@ZsL
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publicfinalstaticint PAGESIZE = 30; Lk2;\ D>
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privateint pageSize = PAGESIZE; :wY(</H
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privateList items; bj,cU)t0
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privateint totalCount; "5@\"L
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privateint[] indexes = newint[0]; g=e~YM85
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privateint startIndex = 0; (d*~Qpi{7
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public PaginationSupport(List items, int 1 Szv4
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totalCount){ _g%,/y 9y
setPageSize(PAGESIZE); D_M73s!U
setTotalCount(totalCount); :&J1#% t
setItems(items); #ba7r
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setStartIndex(0); |h-e+Wh1
} ?fX`z(Z
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public PaginationSupport(List items, int
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totalCount, int startIndex){ Bk@&k}0
setPageSize(PAGESIZE); @dc4v_9
setTotalCount(totalCount); {r?+PQQ#
setItems(items); L0>7v
setStartIndex(startIndex); WZN0`Od
} Ntlbn&lc;D
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public PaginationSupport(List items, int 0?*":o30
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totalCount, int pageSize, int startIndex){ q"VC#97`
setPageSize(pageSize); `>u^Pm
setTotalCount(totalCount); oT i$@q
setItems(items); ?0?+~0sI
setStartIndex(startIndex); ^?S lM
} thSXri?kl
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publicList getItems(){ Y2W{?<99
return items; #B5-3CwB
} 1AQ3<
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publicvoid setItems(List items){ 9#1Jie$
this.items = items; G8lTIs4u;
} =8AL>:_
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publicint getPageSize(){ R=
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return pageSize; 5`)[FCQ
} <q:2' 4o
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publicvoid setPageSize(int pageSize){ Ws:+P~8
this.pageSize = pageSize; 7T?T0x3>
} P\&n0C~
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publicint getTotalCount(){ 7~H"m/;U&
return totalCount; ne# %Gr
} +HEL ^
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publicvoid setTotalCount(int totalCount){ zKFiCP
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if(totalCount > 0){ ntn ~=oL
this.totalCount = totalCount; G\|P3j
int count = totalCount / &H/3@A3
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pageSize; 3u oIYY
if(totalCount % pageSize > 0) :?:R5_Nd=
count++; I@ D<rjR
indexes = newint[count]; 3XhLn/@
for(int i = 0; i < count; i++){ V3$zlzSm,
indexes = pageSize * e#^vA$d
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} eKe[]/}e9
}else{ OySn[4`(i
this.totalCount = 0; e7n`fEpO
} bdj')%@n
} 3^]Kd
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publicint[] getIndexes(){ h%&2M58:
return indexes; oiItQ4{<
} K
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publicvoid setIndexes(int[] indexes){ -932[+
this.indexes = indexes; (S8hr,%n
} K}QZdN']
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publicint getStartIndex(){ E+P-)bRa
return startIndex; QLb!e"C
} 95*=&d
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publicvoid setStartIndex(int startIndex){ |M|>/U 8
if(totalCount <= 0) bf/z
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this.startIndex = 0; Xbc:Vr
elseif(startIndex >= totalCount) =W"9a\m
this.startIndex = indexes Oe&gTXo
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[indexes.length - 1]; HJ!P]X_J1
elseif(startIndex < 0) WnQ+
this.startIndex = 0; ?-=<7
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else{ %)=c#H1
this.startIndex = indexes KA
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[startIndex / pageSize]; RC^k#+
} yK w.69.
} _FzAf5DO
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publicint getNextIndex(){ O[ug7\cl+
int nextIndex = getStartIndex() + B1o*phM
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pageSize; (
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if(nextIndex >= totalCount) F+/#ugI
return getStartIndex(); )@6iQ
else w5q'M
return nextIndex; FLQ>,=O
} _.5ABE
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publicint getPreviousIndex(){ ^@;P -0Sy
int previousIndex = getStartIndex() - R?8/qGSVqJ
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pageSize; 3e1^r_YI
if(previousIndex < 0) B dxV [SF
return0; DS=Dg@y
else BoofJm
return previousIndex; ?'^yw C`
} U\6Ee-1#_
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} uwu`ms7z 2
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抽象业务类 &W
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java代码: 4GexYDk'#
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/** }M &hcw<
* Created on 2005-7-12
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*/ b#Vm;6BHD1
package com.javaeye.common.business; .|GnTC q
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import java.io.Serializable; a
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import java.util.List; h`:B8+k
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import org.hibernate.Criteria;
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import org.hibernate.HibernateException; ?A~a}bFZ
import org.hibernate.Session; 6bUcrw/#
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import org.hibernate.criterion.DetachedCriteria; :CG;:( |
import org.hibernate.criterion.Projections; 43N=OFU
import 'Xg9MS&
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org.springframework.orm.hibernate3.HibernateCallback; >7 qZ\#
import p&ZLd`[
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org.springframework.orm.hibernate3.support.HibernateDaoS a@N
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upport; #XeabcOQ
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import com.javaeye.common.util.PaginationSupport; bOK0^$k
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public abstract class AbstractManager extends z}2
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HibernateDaoSupport { ig4mj47wJ
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privateboolean cacheQueries = false; [wcp2g3Px
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privateString queryCacheRegion; ,pa=OF
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publicvoid setCacheQueries(boolean J;Eg"8x]
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cacheQueries){ q[%SF=~<k{
this.cacheQueries = cacheQueries; $i$Z+-W4'
} U9h@1:
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publicvoid setQueryCacheRegion(String >{#QS"J#
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queryCacheRegion){ M$2lK^2L
this.queryCacheRegion = @T~~aQFk
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queryCacheRegion; n hGh5,
} y-)5d
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publicvoid save(finalObject entity){ xU'% 6/G
getHibernateTemplate().save(entity); V)cL=4G
} `<*
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publicvoid persist(finalObject entity){ ]/od p/jm
getHibernateTemplate().save(entity); MO_;8v~0
} h2vD*W
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publicvoid update(finalObject entity){
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getHibernateTemplate().update(entity); SHN'$f0Mb
} YfVZ59l4y6
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publicvoid delete(finalObject entity){ I5w>*F
getHibernateTemplate().delete(entity); R<e ~Cb-
} pSS8 %r%S'
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publicObject load(finalClass entity, n<Z1i)
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finalSerializable id){ fk(h*L|sI
return getHibernateTemplate().load
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(entity, id); /xkF9
}
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publicObject get(finalClass entity, a f UOIM
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finalSerializable id){ l6< bV#_qe
return getHibernateTemplate().get 7SjWofv
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(entity, id); ] F2{:RW
} <CGJ:% AY
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publicList findAll(finalClass entity){ v)rQ4
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return getHibernateTemplate().find("from 7oZtbBs]M
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" + entity.getName()); N6%M+R/Q
} 7^DN8g"&\
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publicList findByNamedQuery(finalString y/!jC]!+c
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namedQuery){ GA2kg7
return getHibernateTemplate H]VoXJ\*
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().findByNamedQuery(namedQuery); nBGcf(BE.$
} R9O1#s^
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publicList findByNamedQuery(finalString query, Q ;$NDYV1
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finalObject parameter){ &v<Am%!N
return getHibernateTemplate /@+[D{_Fw
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().findByNamedQuery(query, parameter); 5ii:93Hlj
} h"On9
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publicList findByNamedQuery(finalString query, 3Jw}MFFV
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finalObject[] parameters){ (GbZt{.
return getHibernateTemplate x4;ndck%U
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().findByNamedQuery(query, parameters); </9@RO
} 0i/!nke.
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publicList find(finalString query){ Gw?$.@L'I6
return getHibernateTemplate().find e\'=#Hw
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(query); lW3wmSWn%
} d @>1m:p
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publicList find(finalString query, finalObject K)9+3(?
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parameter){ P2sM3C
return getHibernateTemplate().find Q7XlFjzcm
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(query, parameter); Q(h/C!rKe
} M 3c
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public PaginationSupport findPageByCriteria |J^$3RX
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(final DetachedCriteria detachedCriteria){ y\c-I!6>26
return findPageByCriteria <F-W fR
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); H:.l:PJ
} MNd[Xzm
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public PaginationSupport findPageByCriteria \#q|.d$u
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(final DetachedCriteria detachedCriteria, finalint j2Uu8.8d
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startIndex){ ~<q^4w.=7C
return findPageByCriteria (K3eb
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(detachedCriteria, PaginationSupport.PAGESIZE, kyu
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startIndex); H:_R[u4r
} c,_??8
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public PaginationSupport findPageByCriteria fE,Io3
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(final DetachedCriteria detachedCriteria, finalint -1c{Jo
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pageSize, sH /08Z
finalint startIndex){ =w2_1F"
return(PaginationSupport) /'Q2TLy=
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getHibernateTemplate().execute(new HibernateCallback(){ 22r$Ri_>
publicObject doInHibernate J~k'b2(p3
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(Session session)throws HibernateException { >j_N6B!
Criteria criteria = .ly K
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detachedCriteria.getExecutableCriteria(session); GLr7sack
int totalCount = (V9 ;
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((Integer) criteria.setProjection(Projections.rowCount ^2-t|E=
t$-!1jq
()).uniqueResult()).intValue(); ,8Q&X~$rY
criteria.setProjection OGAC[s~V
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(null); 98LyzF9
List items = :C9vs
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criteria.setFirstResult(startIndex).setMaxResults R;`C;Rbf
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(pageSize).list(); 'rDai[
PaginationSupport ps = p-JGDjR0G
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new PaginationSupport(items, totalCount, pageSize, @tg4rl
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startIndex);
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return ps; 0=Mu|G|Z
} _FtsO<p)"
}, true); QI*<MF,1
} ,WQg.neOA
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public List findAllByCriteria(final K410.o/=-
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DetachedCriteria detachedCriteria){ h"t\x}8qq
return(List) getHibernateTemplate vk.P| Y-;
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().execute(new HibernateCallback(){ 8=,-r`oNy
publicObject doInHibernate (qdvvu#E
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(Session session)throws HibernateException { 'ocPG.PaU
Criteria criteria = = ow=3Ku
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detachedCriteria.getExecutableCriteria(session); Z,7VOf6g
return criteria.list(); 12HE=
} <P.'r,"[
}, true); U*:E|'>
} ]'5 G/H5?;
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public int getCountByCriteria(final ,v_NrX=f?
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DetachedCriteria detachedCriteria){ "WZ |
Integer count = (Integer) Hp5.jor(k
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getHibernateTemplate().execute(new HibernateCallback(){ {.o@XP,.
publicObject doInHibernate 3{9d5p|\i
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(Session session)throws HibernateException { 3 @%XR8ss
Criteria criteria = <d~si^*\ch
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detachedCriteria.getExecutableCriteria(session); j9~lf
return
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criteria.setProjection(Projections.rowCount RZP7h>y6@
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()).uniqueResult(); +0g L!r
} l;i/$Yu7
}, true); -mw`f)?Ev
return count.intValue(); p((a(Q/
} bk:mk[
} KvXFzx|A
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用户在web层构造查询条件detachedCriteria,和可选的 (!%9#
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 ziC%Q8
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PaginationSupport的实例ps。 IPf>9#L
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ps.getItems()得到已分页好的结果集 Go(Td++HS
ps.getIndexes()得到分页索引的数组 ]i\;#pj}
ps.getTotalCount()得到总结果数 n&3}F?
ps.getStartIndex()当前分页索引 GQ2/3kt
ps.getNextIndex()下一页索引 ym_p49
ps.getPreviousIndex()上一页索引 tmi)LRF
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 (dTQ,0
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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 Up5 |tx7
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一下代码重构了。 &O#,"u/q`
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我把原本我的做法也提供出来供大家讨论吧: .FG%QF F~
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首先,为了实现分页查询,我封装了一个Page类: H*Tzw,f~ v
java代码: nF$HWp>
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/*Created on 2005-4-14*/ jl5&T{z
package org.flyware.util.page; )Z)Gb~G
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/** |-L7qZu%
* @author Joa @qEUp7W.?
* 3OFI>x,h
*/ bEln.)
publicclass Page { o59b#9
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/** imply if the page has previous page */ SEVB.;
privateboolean hasPrePage; ~LQzt@G4
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/** imply if the page has next page */ >wb Uxl%{5
privateboolean hasNextPage; b0Dco0U(
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/** the number of every page */ ?tA%A
privateint everyPage; f-p$4%(
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/** the total page number */ ;cB3D3fR.
privateint totalPage; SP/'4m
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