Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 (E0WZ$f}
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 <lFHmi$qt{
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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 t#P7'9Se8
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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 [!%5(Ro_
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分页支持类: *Hn=)q
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java代码: Fxa{
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package com.javaeye.common.util; poafGoH-Y
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import java.util.List; @lDnD%vZ`
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publicclass PaginationSupport { 9<rs3 84
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publicfinalstaticint PAGESIZE = 30; OSO MFt
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privateint pageSize = PAGESIZE; Rp2h[_>
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privateList items; 8g8eY pG
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privateint totalCount; jX4$PfOhR
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privateint[] indexes = newint[0]; -sv%A7i
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privateint startIndex = 0; l7T?Yx j
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public PaginationSupport(List items, int ?wkT=mv
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totalCount){ W>!:K^8]
setPageSize(PAGESIZE); dn'|~zf.
setTotalCount(totalCount); Sm {Sq
setItems(items); ugN%8N
setStartIndex(0); 02EX_tt),
} Yz2N(g[
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public PaginationSupport(List items, int L=;T$4+p
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totalCount, int startIndex){ nL^7t7mp
setPageSize(PAGESIZE); `%[m%Y9h
setTotalCount(totalCount); c86?-u')
setItems(items); }f;TG:6
setStartIndex(startIndex); /Zs_G=\>
} &zgliT!If
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public PaginationSupport(List items, int z4D)Xy"/
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totalCount, int pageSize, int startIndex){ q<.k:v&
setPageSize(pageSize); U^[AW$WzU
setTotalCount(totalCount); i;~.kgtq4
setItems(items); :-59~8&
setStartIndex(startIndex); W"s/8;
} nT:<_'!
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publicList getItems(){ l@w\
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return items; ?r|iZKa
} & +`g~6U
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publicvoid setItems(List items){ [}Xw/@Uc;
this.items = items; Wx#l}nD
} ? Lxc1
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publicint getPageSize(){ V G7#C@>Z
return pageSize; vt"bB
} bO$KV"*!
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publicvoid setPageSize(int pageSize){ <J~6Q
this.pageSize = pageSize; XjzGtZ#6
} g3'dkS!
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publicint getTotalCount(){ ?2o+x D2
return totalCount; DJdhOLx
} Q& d;UVp
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publicvoid setTotalCount(int totalCount){ ,b^jAzow
if(totalCount > 0){ 30w(uF
this.totalCount = totalCount; -h|[8UG^b
int count = totalCount / |4BD
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pageSize; '_DB0_Dp
if(totalCount % pageSize > 0) GZ5 DI+3
count++; 4VF]tX?o
indexes = newint[count]; (JOR:
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for(int i = 0; i < count; i++){ Z! /_H($
indexes = pageSize * Yt_tAm
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} j?tE#
}else{ +#>nOn(B
this.totalCount = 0; 6 Yva4Lv
} 6C"${}SF`
} jN=
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publicint[] getIndexes(){ GRj [2I7:
return indexes; Su@V5yz
} 3&[ d.,/
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publicvoid setIndexes(int[] indexes){ +Y+fM
this.indexes = indexes; 0%rE*h9+
} wmbG$T%k
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publicint getStartIndex(){ 4Af7x6a;
return startIndex; DcRoW
} b~ig$!N]
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publicvoid setStartIndex(int startIndex){ S{XO3
if(totalCount <= 0) |'}r-}
this.startIndex = 0; V@G|2ZI
elseif(startIndex >= totalCount) UaXIrBc
this.startIndex = indexes ;\13x][
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[indexes.length - 1]; NP\/9
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elseif(startIndex < 0) 4%yeEc;z
this.startIndex = 0; R Ee~\n+P^
else{ BUI#y `J
this.startIndex = indexes ;x|?N*
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[startIndex / pageSize]; `}
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} %dd B$(
} Xa'b@*o&
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publicint getNextIndex(){ P
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int nextIndex = getStartIndex() + |gk"~D
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pageSize; ?*q-u9s9
if(nextIndex >= totalCount) rV%;d[LB
return getStartIndex(); ki`ur%h
else !8
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return nextIndex; $Vs5d=B
} 8v^AVg
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publicint getPreviousIndex(){ >A L^y(G
int previousIndex = getStartIndex() - j=Q ?d]
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pageSize; SrdCLT8
if(previousIndex < 0) "5sUE!)f
return0; 0x,4H30t(
else }lx'NY~(W
return previousIndex; }vF=XA
} apxq] !
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抽象业务类 #zn`)n
java代码: S6yLq|W0
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/** .'1]2/ad
* Created on 2005-7-12 R|O^7o
*/ 1$yS Ii
package com.javaeye.common.business; 2+YM .Zl
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import java.io.Serializable; u69G
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import java.util.List; :N4?W}r.
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import org.hibernate.Criteria; ]MMXpj,9h
import org.hibernate.HibernateException; RL"hAUs_1
import org.hibernate.Session; @G>&Gu;5
import org.hibernate.criterion.DetachedCriteria; 90Z4saSUw
import org.hibernate.criterion.Projections; y8di-d3_
import ;ejtP #$
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org.springframework.orm.hibernate3.HibernateCallback; 2Nx#:Rz
import 3SF J8
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org.springframework.orm.hibernate3.support.HibernateDaoS b~rlh=(o#_
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upport; _#E@&z".L
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import com.javaeye.common.util.PaginationSupport; d^aLue>g;+
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public abstract class AbstractManager extends u|ru$cIo
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HibernateDaoSupport { "SwM%j
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privateboolean cacheQueries = false; LaIH3!M3
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privateString queryCacheRegion; m&6I@S2
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publicvoid setCacheQueries(boolean W^9=z~-h
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cacheQueries){ G8hDR^ra
this.cacheQueries = cacheQueries; /5R?(-
} c~Z\|Y`#B
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publicvoid setQueryCacheRegion(String G]>P!]
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queryCacheRegion){ NK(; -~{P
this.queryCacheRegion = YjeHNPf
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queryCacheRegion; ddeH-Z
} >Q# !.lH$W
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publicvoid save(finalObject entity){ 0p \,}t\E
getHibernateTemplate().save(entity); wArtg'=X
} 5sF?0P;ln
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publicvoid persist(finalObject entity){ .Aa(
getHibernateTemplate().save(entity); _dw6 C2]P
} - z"D_5
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publicvoid update(finalObject entity){ CEb al\R
getHibernateTemplate().update(entity); 6%UhP;(
} PqwoZo0j
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publicvoid delete(finalObject entity){ =M/($PA
getHibernateTemplate().delete(entity); 8` f=Eh
} ew6\Z$1c~
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publicObject load(finalClass entity, <<ifd?
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finalSerializable id){ ,~xX[uB
return getHibernateTemplate().load 4>8'.8S
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(entity, id); 75#&hi/~
} JlN<w
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publicObject get(finalClass entity, J@pCF@'
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finalSerializable id){ >_um-w #C
return getHibernateTemplate().get g:>Mooxzi
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(entity, id); _,9/g^<
} 6`hHx=L
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publicList findAll(finalClass entity){ srfM"Lb'
return getHibernateTemplate().find("from 3eS
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" + entity.getName()); ){{]3r
} Snf1vH
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publicList findByNamedQuery(finalString qHQ#^jH
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namedQuery){ z>./lu\
return getHibernateTemplate lCMU{)
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().findByNamedQuery(namedQuery); h$y0>eMWs
} )'gO?cN
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publicList findByNamedQuery(finalString query, Qh.
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finalObject parameter){ /6@Wm?`DB
return getHibernateTemplate H-aSLc
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().findByNamedQuery(query, parameter); }
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} Y^W.gGM
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publicList findByNamedQuery(finalString query, \+B+M 7
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finalObject[] parameters){ C 9:5c@G
return getHibernateTemplate e^ygQ<6%
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().findByNamedQuery(query, parameters); ;F!wyTF>}
} 4chSo.= 4V
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publicList find(finalString query){ }vLK-Vv
return getHibernateTemplate().find 3d@$iAw1<
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(query); N [iv.B
} ,5L[M&5
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publicList find(finalString query, finalObject HC*V\vz
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parameter){ `d[ja,
return getHibernateTemplate().find }6V` U9^g
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(query, parameter); oAgO3x
} d;D8$q)8Q
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public PaginationSupport findPageByCriteria pK~K>8\
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(final DetachedCriteria detachedCriteria){ _,JdL'[d
return findPageByCriteria ` E2@GX+,
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); 1Gojuey
} y-iuOzq4
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public PaginationSupport findPageByCriteria $`&uu
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(final DetachedCriteria detachedCriteria, finalint ,mE*k79L6
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startIndex){ &91U(Go
return findPageByCriteria +EWfsKz
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(detachedCriteria, PaginationSupport.PAGESIZE, loLN
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startIndex); Ws;}D}+
} $0MP*TFWa
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public PaginationSupport findPageByCriteria MWS=$N)v*
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(final DetachedCriteria detachedCriteria, finalint pv2u.qg5z
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pageSize, 3d2|vQx,K
finalint startIndex){ Y4 Y;xK"
return(PaginationSupport) j<LDJi>O
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getHibernateTemplate().execute(new HibernateCallback(){ 6^]Y])
publicObject doInHibernate BQol>VRu
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(Session session)throws HibernateException { }!-K )j .
Criteria criteria = C>vp
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detachedCriteria.getExecutableCriteria(session); )PU?`yLTr
int totalCount = JZ5NQ)sX
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((Integer) criteria.setProjection(Projections.rowCount X~O2!F
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()).uniqueResult()).intValue(); 3UIR^Rh+
criteria.setProjection gt9{u"o
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(null); 6Y|jK<n?H
List items = {/x["2a1
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criteria.setFirstResult(startIndex).setMaxResults qn+b*4
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(pageSize).list(); fJ3*'(
PaginationSupport ps = ?=%Q$|]-
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new PaginationSupport(items, totalCount, pageSize, Q]Fm4
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startIndex); /=zzym~<>
return ps; S?bG U8R5
} ]8|cVGMa
}, true); ab 1qcQ<
} EPQ~V
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public List findAllByCriteria(final d85\GEF9i
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DetachedCriteria detachedCriteria){ ubn`w=w$
return(List) getHibernateTemplate >4A~?=
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().execute(new HibernateCallback(){ H*DWDJxmV
publicObject doInHibernate ,haCZH{
ic}M)S FD;
(Session session)throws HibernateException { HCh;Xi
Criteria criteria = @Fp-6J
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detachedCriteria.getExecutableCriteria(session); MX%D%}N
return criteria.list(); b5hJaXJN
} [/}y!;3iXM
}, true); qV%t[>
} #OKzJ"g
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public int getCountByCriteria(final nwk66o:|
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DetachedCriteria detachedCriteria){ :wJ=t/ho
Integer count = (Integer) P<+5So0
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getHibernateTemplate().execute(new HibernateCallback(){ [Yx)`e
publicObject doInHibernate fI2/v<[
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(Session session)throws HibernateException { &j\<UPn
Criteria criteria = D:9/;9V
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detachedCriteria.getExecutableCriteria(session); SCClD6k=V
return HSk gS
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criteria.setProjection(Projections.rowCount AnV\{A^
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()).uniqueResult(); ;- D1n
}
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}, true); PQ`p:=~>:i
return count.intValue(); 7Vf2Qx1_
} "T/
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} 289@O-
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用户在web层构造查询条件detachedCriteria,和可选的 mC
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 _zG9.?'b3
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PaginationSupport的实例ps。 )$#]h]ac
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ps.getItems()得到已分页好的结果集 Ih*}1D)7
ps.getIndexes()得到分页索引的数组 ;$|[z<1RdW
ps.getTotalCount()得到总结果数 3PB#m.N<
ps.getStartIndex()当前分页索引 P@ewr}
ps.getNextIndex()下一页索引 @add'>)
ps.getPreviousIndex()上一页索引 :` >|N|i
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 60KhwD1
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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 N=J$+
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一下代码重构了。 I\JJ7/S`t
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我把原本我的做法也提供出来供大家讨论吧: *Mf;
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首先,为了实现分页查询,我封装了一个Page类: <eU28M?\
java代码: FNpMu3Q
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/*Created on 2005-4-14*/ k r0PL)$
package org.flyware.util.page; #hEN4c[Ex
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/** vkdU6CZO
* @author Joa ze!S4&B
* >[ r
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*/ Qp{gV Ys
publicclass Page { (fmcWHs
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/** imply if the page has previous page */ Qe=,EXf
privateboolean hasPrePage; k!e \O> +
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/** imply if the page has next page */ >}#h
privateboolean hasNextPage; &61;v@
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7
/** the number of every page */ W2L:
privateint everyPage; D9H(kk
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/** the total page number */ j4wcxZYY~
privateint totalPage; ,?Pn-aC+
d,}fp)
/** the number of current page */ q\Cg2[nn2
privateint currentPage; M_tY: v
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/** the begin index of the records by the current ~~[Sz#(
2}Dd{kC-
query */ YfBb=rN2s
privateint beginIndex; 0-H! \IB
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/** The default constructor */ }q1@[
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public Page(){ 3L$_OXx
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} %(a<(3r
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/** construct the page by everyPage L8K=Q
* @param everyPage 5y7rY!]Bf
* */ #3@ Du(_n
public Page(int everyPage){ >$=-0?.
this.everyPage = everyPage; ]3tg|?%B
} ;SAurG$
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/** The whole constructor */ o:ki IZ]
public Page(boolean hasPrePage, boolean hasNextPage, ~F8M_
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int everyPage, int totalPage,
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int currentPage, int beginIndex){ Fj\}&H*+
this.hasPrePage = hasPrePage; %,$Ms?,n`
this.hasNextPage = hasNextPage; t3ua5xw
this.everyPage = everyPage; uP<w rlW
this.totalPage = totalPage; 5urM,1SQ@
this.currentPage = currentPage; wjk-$p
this.beginIndex = beginIndex; sS 5 ]d8
} Rk2V[R.`S
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/** DA)+)PhY7K
* @return Q3MG+@) S
* Returns the beginIndex. D"o}X TH
*/ 1PWs">*(
publicint getBeginIndex(){ Bw-<xwD
return beginIndex; T'9I&h%\
} yX%T-/XJ
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/** KK;3<kX
* @param beginIndex y6.}h9~
* The beginIndex to set. ~_WsjD0O
*/ pEk^;
publicvoid setBeginIndex(int beginIndex){ ,Y&LlB 2
this.beginIndex = beginIndex; /(C?3}}L
} }:u" ?v=|j
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/** 1qWIku
* @return K*;e>{p
* Returns the currentPage. hn9'M!*:O
*/ w~J 7|8Y
publicint getCurrentPage(){ 9"mOjL
return currentPage; ;V(- ;O
} 8wGq:@#=
vK2sj1Hzr
/** ~l$u~:4Ob
* @param currentPage nR)/k,3W
* The currentPage to set. [.\uHt
*/ Df;EemCh
publicvoid setCurrentPage(int currentPage){ >|%dN
jf@Q
this.currentPage = currentPage; RUcpdeo
} 5/j7 C>
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/** _2Sb?]Xn
* @return 3xS+Pu\)
* Returns the everyPage. utIR\e#:B
*/ :V1ttRW}52
publicint getEveryPage(){ eliT<sw8
return everyPage; A/n-.ci
} +2%ih!
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/** 2E~WcB
* @param everyPage W.OcmA>x
* The everyPage to set. Kx.'^y
*/ ]h4^3
publicvoid setEveryPage(int everyPage){ :;[pl|}tM
this.everyPage = everyPage; _ndc^OG
} y]|Hrx
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/** \_?A8F
* @return _'9("m V
* Returns the hasNextPage. [fF0Qa-
*/ r':wq
publicboolean getHasNextPage(){ gycjIy@t
return hasNextPage; K)z{R n
} 6"@+Jz
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/** EBjSK/
* @param hasNextPage MB]8iy8
* The hasNextPage to set. @Qw~z0PE<l
*/ ^(<Ecdz(
publicvoid setHasNextPage(boolean hasNextPage){ e~#;ux
this.hasNextPage = hasNextPage; &R