Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 n[:AV
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 VE"0VB.
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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 9
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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 LOUKURe E
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分页支持类: e9hVX[uq
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java代码: 3g#=sd!0O@
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package com.javaeye.common.util; \%?8jQ'tX
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import java.util.List; {p*hN i)0
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publicclass PaginationSupport { O$umu_
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publicfinalstaticint PAGESIZE = 30; c>WpO Z,
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privateint pageSize = PAGESIZE; 3| '#n[3
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privateList items; wI]R+.
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privateint totalCount; CMxjX
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privateint[] indexes = newint[0]; ~SR(K{nf#.
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privateint startIndex = 0; gC_s\WU
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public PaginationSupport(List items, int Xm^h5jAr
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totalCount){ e"s {_V
setPageSize(PAGESIZE); N} x/&e
setTotalCount(totalCount); D@rn@N
setItems(items); 1nlE3Y?AV
setStartIndex(0); R!V5-0%
} Puth8$
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public PaginationSupport(List items, int c]aK
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totalCount, int startIndex){ ^;CR0.4
setPageSize(PAGESIZE); T?]kF-
setTotalCount(totalCount); =S[FJaIu7
setItems(items); /VmCN]2AZ
setStartIndex(startIndex); =FD`A#\C~
} X4P}aC
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public PaginationSupport(List items, int [nN\{"~O
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totalCount, int pageSize, int startIndex){ ~g
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setPageSize(pageSize); A}#]g>L
setTotalCount(totalCount); AK~`pq[.
setItems(items); HV$9b~(
setStartIndex(startIndex); &8X
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}
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publicList getItems(){ m>abK@5na
return items; -e`oW.+
} ,.6J6{
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publicvoid setItems(List items){ dY4k9p8
this.items = items; M ~ i+F0
} >TlW]st
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publicint getPageSize(){ kY'<u
return pageSize; "J8;4p
} _Ra<|NVQh
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publicvoid setPageSize(int pageSize){ 4[LLnF--
this.pageSize = pageSize; ~<2 IIR$H
} !sfXq"F
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publicint getTotalCount(){ $TD~k;
return totalCount; [x2JFS#4
} 54q4CagFq
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publicvoid setTotalCount(int totalCount){ w(76H^e
if(totalCount > 0){ ID67?:%r
this.totalCount = totalCount; K3vseor
int count = totalCount / Usa+b
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pageSize; DA<F{n.Z:
if(totalCount % pageSize > 0) YSR mt/
count++; b]!9eV$
indexes = newint[count]; ,O:EX0
for(int i = 0; i < count; i++){ o"rq/\ovv
indexes = pageSize * r\$6'+Si
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i; QGs1zfh*
} T>}0) s
}else{ Bk?8zYp
this.totalCount = 0; T
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} bA}AD`5
} {Ge+O<mD
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publicint[] getIndexes(){ D
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return indexes; 96(R'^kNX
} `I5O4|K)
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publicvoid setIndexes(int[] indexes){ Iz
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this.indexes = indexes; ?Bo?JMV
} OFc\fW#
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publicint getStartIndex(){ ""co6qo#>
return startIndex; 1HMUHZT
} >\V6+$cNp
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publicvoid setStartIndex(int startIndex){ zVSx$6eiU
if(totalCount <= 0) f}^I=pS&
this.startIndex = 0; \+-zRR0
elseif(startIndex >= totalCount) *)u?~r(F
this.startIndex = indexes 5L8&/EN9-
^:`oP"%-T
[indexes.length - 1]; sLb8*fak
elseif(startIndex < 0) cA D[3b[Gk
this.startIndex = 0; N_ UQ
else{ 9YB2e84j
this.startIndex = indexes (+*
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[startIndex / pageSize]; QV7,G9
} cv}aS_`f
} <OTWT`G2
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publicint getNextIndex(){ -<_QF82
int nextIndex = getStartIndex() + eP "`,<
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pageSize; MDJc[am
if(nextIndex >= totalCount) (8.{+8o
return getStartIndex(); j~bAbOX12
else ((XE\V\}Z
return nextIndex; m`z7fi7u
} /
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publicint getPreviousIndex(){ #ZJMlJ:q`"
int previousIndex = getStartIndex() - Vtr3G.P^
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pageSize; Hou*lCA
if(previousIndex < 0) t8QRi!\=
return0; F|>05>8
else (Yv{{mIy
return previousIndex; B
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} T-'~? [v
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} ^i+[m
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抽象业务类 B{C_hy-fw
java代码: d+;gw*_Ei
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/** LXj5R99S
* Created on 2005-7-12 8$0\J _
*/ jNA1O68N
package com.javaeye.common.business; |~WYEh
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import java.io.Serializable; ?c]n^GvG
import java.util.List; jfD1
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import org.hibernate.Criteria; t V03+&jF
import org.hibernate.HibernateException; qTT,U9]:
import org.hibernate.Session; Tk*w3c"$
import org.hibernate.criterion.DetachedCriteria; T>A{qu
import org.hibernate.criterion.Projections; F30
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import XM/vDdR
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org.springframework.orm.hibernate3.HibernateCallback; lT'9u,6
import T dk
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org.springframework.orm.hibernate3.support.HibernateDaoS *FK`&(B+}
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upport; ib$nc2BPb
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import com.javaeye.common.util.PaginationSupport; T-gk <V
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public abstract class AbstractManager extends + H_MV=A^
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HibernateDaoSupport { Zp&@h-%YoD
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privateboolean cacheQueries = false; S|em[D[Y^
/*$hx @ih
privateString queryCacheRegion; #]E(N~
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publicvoid setCacheQueries(boolean @%hCAm
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cacheQueries){ C3XmK}h
this.cacheQueries = cacheQueries; &H||&Z[pk
} M6rc!K
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publicvoid setQueryCacheRegion(String 9MY7a=5E~
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queryCacheRegion){ \(
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this.queryCacheRegion = [8XLK 4e
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queryCacheRegion; $s\UL}Gc
} ;@3FF
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publicvoid save(finalObject entity){ ;`dh
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getHibernateTemplate().save(entity); WGu%7e]
} x%N\5 V1
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publicvoid persist(finalObject entity){ uH@FU60
getHibernateTemplate().save(entity); _Ov;4nt!
} 445o DkG
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publicvoid update(finalObject entity){ VZy4_v=
getHibernateTemplate().update(entity); ?4 S+edX
} #]]Su91BA
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publicvoid delete(finalObject entity){ &fOdlQ?
getHibernateTemplate().delete(entity); e:w&(is
} yX!HZu;j
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publicObject load(finalClass entity, =1p8i
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finalSerializable id){ !#2=\LUC
return getHibernateTemplate().load ?GA&f2]a
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(entity, id); "LhvzM-<8
} "O[j!fG8,
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publicObject get(finalClass entity, O#a6+W"U
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finalSerializable id){ N K]B?
return getHibernateTemplate().get X2|Y
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(entity, id); \x{;U#B[3>
} l_rn++
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publicList findAll(finalClass entity){ !v.9"!' N
return getHibernateTemplate().find("from #R0A= !
. @q-B+Eg
" + entity.getName()); ?, r~=
} X-LA}YH=tS
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publicList findByNamedQuery(finalString ;%C'FV e]
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namedQuery){ )E#2J$TD
return getHibernateTemplate oR1^/e
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().findByNamedQuery(namedQuery); -]uUY e
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} I<td1Y1q
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publicList findByNamedQuery(finalString query, >'uU)Y{
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finalObject parameter){ 4+$b~u
return getHibernateTemplate iIT8H\e
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().findByNamedQuery(query, parameter); |'O[7uT
} D]a:@x`+Bz
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publicList findByNamedQuery(finalString query, dy__e ^qi
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finalObject[] parameters){ YTQt3=1ii
return getHibernateTemplate "@A![iP
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().findByNamedQuery(query, parameters); J7D}%
} f3j{V N
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publicList find(finalString query){ [H<bh%
return getHibernateTemplate().find O,bkQY$v
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(query); M->*{D@a
} 9E2j!
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publicList find(finalString query, finalObject 0P^L }VVX
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parameter){ =*qD4qYA
return getHibernateTemplate().find &6 s) X
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(query, parameter); ?[<Tx-L
} j"^+oxH
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public PaginationSupport findPageByCriteria /={Js*
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(final DetachedCriteria detachedCriteria){ &8&d3EQ
return findPageByCriteria .:p2Tbo
vb 1@yQ
(detachedCriteria, PaginationSupport.PAGESIZE, 0); Z=B_Ty
} FGO[
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public PaginationSupport findPageByCriteria SK1!thQy
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(final DetachedCriteria detachedCriteria, finalint e^4 p%
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startIndex){ dkgSvi :!
return findPageByCriteria YprHwL
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(detachedCriteria, PaginationSupport.PAGESIZE, MV_Srz
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startIndex); }bN%u3mHws
} c4&' D;=
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public PaginationSupport findPageByCriteria Q9}dHIe1E
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(final DetachedCriteria detachedCriteria, finalint iGB_{F~t4}
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pageSize, dm-pxE "
finalint startIndex){ />'V!iWyz
return(PaginationSupport) ;.xoN|Per
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getHibernateTemplate().execute(new HibernateCallback(){ b'MSkEiQG
publicObject doInHibernate Wg{k$T_>
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(Session session)throws HibernateException { ReiB $y6
Criteria criteria = 26X+
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detachedCriteria.getExecutableCriteria(session); f\'{3I29
int totalCount = !O\;Nua
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((Integer) criteria.setProjection(Projections.rowCount '$4O!YI9@
e%8|<g+n6
()).uniqueResult()).intValue(); 8WE{5#oi
criteria.setProjection 0 a]/%y3V
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(null); ^c~)/F/cF
List items = LjL[V'JL
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criteria.setFirstResult(startIndex).setMaxResults {`2R,Jb%S
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(pageSize).list(); H|cNH=
PaginationSupport ps = 85EQ5yY
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new PaginationSupport(items, totalCount, pageSize, $+.l*]
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startIndex); $/6;9d^
return ps; 2[0JO.K
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} *:i1Lv@
}, true); VG/3xR&y
} ikE<=:pe
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public List findAllByCriteria(final yj4+5`|f
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DetachedCriteria detachedCriteria){ Ax !+P\\2~
return(List) getHibernateTemplate 7'NwJ,$6\
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().execute(new HibernateCallback(){ cA6lge<{~
publicObject doInHibernate Vh}SCUof'
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(Session session)throws HibernateException { 9qS"uj
Criteria criteria = uKgZ$-'
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detachedCriteria.getExecutableCriteria(session); 4&/j|9=X
return criteria.list(); ]|<w\\^A
} Xl@cHO=i
}, true); AoA!q>
} Xf)|Pu
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public int getCountByCriteria(final ~=R SKyzt
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DetachedCriteria detachedCriteria){ ]*7Y~dO
Integer count = (Integer) EUsI%p
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getHibernateTemplate().execute(new HibernateCallback(){ hzk6rYg1
publicObject doInHibernate wP"dZagpj
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(Session session)throws HibernateException { eT2*W$
Criteria criteria = <0S=,!
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detachedCriteria.getExecutableCriteria(session); |yo\R{&6
return V.wqZ {G
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criteria.setProjection(Projections.rowCount mo~*C
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()).uniqueResult(); =_YG#yS
} qY 4#V k
}, true); $=?@*p
return count.intValue(); [pVamE
} /c):}PJ^#7
} `K,1K
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用户在web层构造查询条件detachedCriteria,和可选的 b,8{ X<
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 .xBu-?6s6
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PaginationSupport的实例ps。 NH_<q"gT
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ps.getItems()得到已分页好的结果集 ?`J[[",
ps.getIndexes()得到分页索引的数组 ~}Rj$%_
ps.getTotalCount()得到总结果数 r H ~" 4
ps.getStartIndex()当前分页索引 [@4rjGwB
ps.getNextIndex()下一页索引 HYmn:?H
ps.getPreviousIndex()上一页索引 <V>dM4Mkr
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 WOh|U4vt
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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 -(K9s!C!.
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一下代码重构了。 QNDHOo>v
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我把原本我的做法也提供出来供大家讨论吧: "Ky; a?Y
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首先,为了实现分页查询,我封装了一个Page类:
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java代码: s=[h?kB
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/*Created on 2005-4-14*/ H:"maS\I
package org.flyware.util.page; =N 5z@;!
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/** *-xU2
* @author Joa fw[y+Bi&
?
* Qyy.IPTP
*/ kY'T{Sm1^
publicclass Page { LiKxq=K
`mN4_\]
/** imply if the page has previous page */ \rPbK+G.
privateboolean hasPrePage; O(_[ayE
&5:tn=E
/** imply if the page has next page */ B-l'vVx
privateboolean hasNextPage; Uk\Id~xLV
[k-+AA>:
/** the number of every page */ B 2ec@]uD`
privateint everyPage; 36am-G
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/** the total page number */ ?mlNL/:
privateint totalPage; h>Hb`G<
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/** the number of current page */ + T8B:
privateint currentPage; uw2hMt (N
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/** the begin index of the records by the current /JT#^Y
a. z;t8
query */ /q5:p`4{J
privateint beginIndex; IUwm}9Q!
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/** The default constructor */ XQS9,Hl
public Page(){ Zv#Ll@v
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} rylzcN9RM$
M}!2H*
/** construct the page by everyPage PiA0]>
* @param everyPage Q~T$N
* */ L5,NP5RC
public Page(int everyPage){ nR`ov1RH
this.everyPage = everyPage; B7!3-1<k>
} !o$!Fr c
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/** The whole constructor */ t]-5 ]oI
public Page(boolean hasPrePage, boolean hasNextPage, [p<w._b i
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int everyPage, int totalPage, \eFR(gO+
int currentPage, int beginIndex){ ,TFIG^Dvq
this.hasPrePage = hasPrePage; `]W|8M
this.hasNextPage = hasNextPage; |6<p(i7
this.everyPage = everyPage; L`24?Y{
this.totalPage = totalPage; J_;o|gqX
this.currentPage = currentPage; ? YG)I;(
this.beginIndex = beginIndex; o]opdw
} rEF0oJ.
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/** Hhh0T>gi
* @return KRA/MQ^7~U
* Returns the beginIndex. _F`lq_C
*/ bcYF\@};
publicint getBeginIndex(){ 6H7],aMg$A
return beginIndex; 4#lo$#
} !@v7Zu43,
@mfEKU!
/** ^f(@gS}?
* @param beginIndex V 0rZz
* The beginIndex to set. }I>tO9M
*/ LEtG|3Dx
publicvoid setBeginIndex(int beginIndex){ k`N^Vdr
this.beginIndex = beginIndex; 5s].
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} 9th,VnD0
@/31IOIV]`
/** OE- gC2&Bm
* @return ~Rr~1I&mR,
* Returns the currentPage. J Px~VnE%%
*/ yYfsy?3
publicint getCurrentPage(){ hyFyP\u]
return currentPage; 8Q'0h
m?
} {yExQbN
%QP0
/** 2=^m9%
* @param currentPage .qZI$
l.
* The currentPage to set. f=9|b
*/ qXwPDq/
publicvoid setCurrentPage(int currentPage){ &mx)~J^m
this.currentPage = currentPage; Dg?:/=,=9r
} v'3J.?N
.yEBOMNZ
/** \:UIc*S
* @return @qYp>|AF
* Returns the everyPage. [;J>bi;3N
*/ @
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publicint getEveryPage(){ %B.yW`,X
return everyPage; %xyou:~0zs
} K9up:.{QQ
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/** k-^mIJo}
* @param everyPage 5f 5f0|ok
* The everyPage to set. :w^Ed%>y7
*/ #e$5d>j(
publicvoid setEveryPage(int everyPage){ *vwbgJG! *
this.everyPage = everyPage; 73\JwOn~
} &eX!#nQ_.
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/** \r+8qC[,
* @return BNs@n"k
* Returns the hasNextPage. V6,H}k
*/ fd.^h*'mU
publicboolean getHasNextPage(){ ]%u@TK7
return hasNextPage; K42K!8$
} mrF58Uq;A
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/** "[ZB+-|[0
* @param hasNextPage /x
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* The hasNextPage to set. }xh$T'M8
*/ :BV6y|J9O^
publicvoid setHasNextPage(boolean hasNextPage){ B e0ND2oo
this.hasNextPage = hasNextPage; [UWdW
} 9j6QX~,
!*B'?|a<\
/** M# %a(Y3K)
* @return NdD`Hn-
* Returns the hasPrePage. Rx=>6,)'
*/ lUMS;H(
publicboolean getHasPrePage(){ oV|4V:G q
return hasPrePage; lSVp%0jR
} )x=1]T>v"'
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/** 6"&6`f
* @param hasPrePage %_%Q8,W
* The hasPrePage to set. #W.#Hjpp
*/ 2Tp1n8FV
publicvoid setHasPrePage(boolean hasPrePage){ U!*M*s
this.hasPrePage = hasPrePage; _)>_{Pm
} naR0@Q"\h
+{f:cea (1
/** [QoK5Yw{
* @return Returns the totalPage. Ssou
* ?FpWvyz|
*/ &&8IU;J
publicint getTotalPage(){ ij( B,Y
return totalPage; tne ST.
} 7>))D'l57
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/** &-Gqdnc
* @param totalPage afuOeZP
* The totalPage to set. DN-+osPi
*/ -~v2BN/
publicvoid setTotalPage(int totalPage){ c]n1':FT"
this.totalPage = totalPage; QLvHQtzwX
} RL@VSHXc
[ 0KlC1=
} r") `Ph@yp
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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 !Sh&3uy_qN
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个PageUtil,负责对Page对象进行构造: D%OQ e#!
java代码: *rs5]U<
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/*Created on 2005-4-14*/ hIs4@0
package org.flyware.util.page; 0ghGBuv1s
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import org.apache.commons.logging.Log; Dwr)0nk
import org.apache.commons.logging.LogFactory; pN:Kdi
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/** "U>JM@0DNm
* @author Joa Tc>
* .w=/+TA
*/ r~jm`y
publicclass PageUtil { \E72L5nJW
PV'x+bN5
privatestaticfinal Log logger = LogFactory.getLog 4sF"6+%5d
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(PageUtil.class); 4o
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/** H]{v;;'~
* Use the origin page to create a new page C*)3e*T*
* @param page GP!?^r:en
* @param totalRecords ^84G%)`&
* @return rb5~XnJk
*/ EUD~CZhS"k
publicstatic Page createPage(Page page, int ,
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totalRecords){ 8=B|C'>
return createPage(page.getEveryPage(), M -cTRd-i
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page.getCurrentPage(), totalRecords); l&OKBUG
} [842&5Pd?
DBW[{DE
/** WejYy|
* the basic page utils not including exception `<``8
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handler q0i(i.h
* @param everyPage 8Wrh]egu1
* @param currentPage !;&p"E|b#
* @param totalRecords R]}}$R`j
* @return page ]i&6c
*/ dt \TQJc~
publicstatic Page createPage(int everyPage, int ck ]Do!h
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currentPage, int totalRecords){ nhB1D-
everyPage = getEveryPage(everyPage); gp};D
currentPage = getCurrentPage(currentPage); 8;b(0^
int beginIndex = getBeginIndex(everyPage, m,*QP*
nt 81Bk=
currentPage); $UMFNjL
int totalPage = getTotalPage(everyPage, Ygm`ZA y
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totalRecords); 8p^bD}lN7
boolean hasNextPage = hasNextPage(currentPage, cv-PRH#
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totalPage); / ;$#d}R
boolean hasPrePage = hasPrePage(currentPage); {C 6=[
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returnnew Page(hasPrePage, hasNextPage, x5,++7Tz
everyPage, totalPage, w k(VR
currentPage, q.KG^=10
3 R=,1<
beginIndex); R0P
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} nOt&pq7
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privatestaticint getEveryPage(int everyPage){ yh Yb'GK
return everyPage == 0 ? 10 : everyPage; s>B5l2Q4
} j`JMeCG=Ee
V, Z|tB^
privatestaticint getCurrentPage(int currentPage){ s1MErd
return currentPage == 0 ? 1 : currentPage; ,~a QL
} [;r)9mh7
1t:Q_j0Ym
privatestaticint getBeginIndex(int everyPage, int ;kFDMuuO
*;l]8.
currentPage){ H7z,j}l
return(currentPage - 1) * everyPage; )JDs\fUE
} 9A/\h3HrJ
,V,`Jf
privatestaticint getTotalPage(int everyPage, int ^!<U_;+
l7XUXbYp&=
totalRecords){ 03|PYk 6EW
int totalPage = 0; \l'm[jy>
Lz`E;k^
if(totalRecords % everyPage == 0) \s/s7y6b+
totalPage = totalRecords / everyPage; oiF}?:7Q7
else 0ZT5bg_M
totalPage = totalRecords / everyPage + 1 ; MuYk};f
;+e}aER&9
return totalPage; O!mvJD
} 5QW=&zI`=
`_BNy=`s*
privatestaticboolean hasPrePage(int currentPage){ fL_4uC i\
return currentPage == 1 ? false : true; wg7V-+@i
} zcel|oz)
@GBxL*e
privatestaticboolean hasNextPage(int currentPage, Sc>,lIM
S'|,oUWDb
int totalPage){ bV(Y`g
return currentPage == totalPage || totalPage == ujDd1Bxf?
C\S3Gs
0 ? false : true; _K`wG}YIE
} RTvqCp
HTVuStM8
*i\Qo
} D N'3QQn
na#CpS;pc
qIVx9jNN
8qY79)vD4E
"oTHq]Ku
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。 vL|SY_:4
Keuf9u
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 di?K"Z>
G^~k)6v=m
做法如下: x^HGVWw_
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 SFB~
->db
^"VJd[Hn
的信息,和一个结果集List: W}3.E "K
java代码: "8c@sHk(w
"w^!/
#D<C )Q
/*Created on 2005-6-13*/ bP8Sj16q
package com.adt.bo; O;z,qo X
cWEE%
import java.util.List; $Wjww-mx
W,4QzcQR
import org.flyware.util.page.Page; '= _/ 1F*q
NiWa7 /Hr
/** NMW#AZVd
* @author Joa kjW+QT?T&
*/ ZO!I.
publicclass Result { Qt iDTr
<A[E:*`*
private Page page; ~"!]
3C,L
AuUde$l_
private List content; Y,GU%[+
_p#CwExuy
/** CKtB-a
* The default constructor " W!M[qBW
*/ Fw/6?:C}O6
public Result(){ C+?Hm1
super(); 1LqoF{S:
} 6o
|kIBte-
{G|,\O1
/** [DJ flCR&
* The constructor using fields s8QMewU
* D;oe2E{I
* @param page tkVbo.[8K
* @param content pA`+hQNN
*/ nA?`BOe(
public Result(Page page, List content){ hhSy0
this.page = page; XUM!Qv
this.content = content; VcAue!MN
} *YW/_
stG~AC
/** 8;z6=.4xtg
* @return Returns the content. IYqBQnX}oM
*/ @En^wN
publicList getContent(){ g3Ec"_>P
return content;
<p}R~zk
} aHs^tPg
{n(b{ibl
/** ;6gDV`Twy
* @return Returns the page. jYx38_5e
*/ -#0qV:D
public Page getPage(){ tna .52*/
return page; @xQgY*f#
} *n;!G8\
VOKZ dC-
/** p%iGc<vHX
* @param content 3Dg,GaRk
* The content to set. WzAb|&?
*/ JCz@s~f\y
public void setContent(List content){ ]Gpxhg
this.content = content; Yb:\a/ y
} P#pn*L*"T
E>&n.%
/** %dJX-sm@
* @param page 7x#Ckep:I
* The page to set.
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uZ8:f
*/ 4Yxo~ m(
publicvoid setPage(Page page){ ML:Q5 ^`
this.page = page; ^=C{.{n
} ?bPRxR
} "XB[|#&
]NjX?XdX<
O>SLOWgha
x6(~;J
t]>Lh>G
2. 编写业务逻辑接口,并实现它(UserManager, &Q+Ln,(&L
z|=}1;(.
UserManagerImpl) kV?y0J.
java代码: :Mb%A
M>DaQ`b
kz{/(t
/*Created on 2005-7-15*/ "Weg7mc#
package com.adt.service; +hvO^?4j
^9^WuSq
import net.sf.hibernate.HibernateException; &@%W29:
UH]l9Aq$P
import org.flyware.util.page.Page; TS /.`.gT
P6!jRC"52'
import com.adt.bo.Result; X'%E\/~u
&L#UGp$,
/** .zS?9MP
* @author Joa 8*8Zc/{
*/ pF&(7u
publicinterface UserManager { Fkvl%n
9v?N+Rb
public Result listUser(Page page)throws LAVAFlK5
;w:M`#2
HibernateException; Em?d*z
JXCCTUO
} "[vu6 `m?
7#@cz5Su
S?RN?1
!xP8#|1
9&upujVS
java代码: f&}k^>N#3
n.wF&f'D]
n,=VQOu
/*Created on 2005-7-15*/ I([!]z
package com.adt.service.impl; k:JrHBKv\
k9$K}
import java.util.List; Mzsfo;kk+
=3q/F7-
import net.sf.hibernate.HibernateException; mu?Eco`~
[PQ?#:r
import org.flyware.util.page.Page; 7s"<
'cx_F
import org.flyware.util.page.PageUtil; VS9`{
3BB%Z6F
import com.adt.bo.Result; uIcn{RZ_z
import com.adt.dao.UserDAO; A'G66ei
import com.adt.exception.ObjectNotFoundException; "
Om[~-31
import com.adt.service.UserManager; Y3r%B9~
2rmSo&3@s
/** Yiry["[]Q
* @author Joa T_sTC)&a
*/ :/:.Kb
publicclass UserManagerImpl implements UserManager { 8aO~/i:(.
s_x:T<]
private UserDAO userDAO; @7n/Q(
@kk4]:,w
/** -QOw8vm
* @param userDAO The userDAO to set. {LX.iH9}l
*/ [QMu2
publicvoid setUserDAO(UserDAO userDAO){ Sl-v W
this.userDAO = userDAO; 4Fp0ZVT
} &C_'p {G
AFc$%\s4
/* (non-Javadoc) 0TN;86Mo
* @see com.adt.service.UserManager#listUser p[<Dk$7K
QFg sq{
(org.flyware.util.page.Page) 0GB:GBhZ
*/ Swp;HW7x
public Result listUser(Page page)throws |AcRIq
fRy^Q_~,
HibernateException, ObjectNotFoundException { -:30:oq
int totalRecords = userDAO.getUserCount(); ~n[xtWO0
if(totalRecords == 0) ox:[f9.5
throw new ObjectNotFoundException
Vm(1G8 a
GDu~d<R H
("userNotExist"); 2R=DB`3
page = PageUtil.createPage(page, totalRecords); bhkUKxd
List users = userDAO.getUserByPage(page); SG-'R1
J
returnnew Result(page, users); }:u~K;O87
} FL(6?8zK
(S xR`QP?,
} Mu{;vf|j
Nc+,&R13m
$-#Yl&?z9
58%#DX34M
S:TgFt0
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 e*@{%S
A-,up{g
询,接下来编写UserDAO的代码: ##@$|6
3. UserDAO 和 UserDAOImpl: ?CC"Yij
java代码: )Psb>'X
~=8uN<
{Zh>mHW3
/*Created on 2005-7-15*/ G
16!eDMt
package com.adt.dao; 6&bY} i^K
/%0<p,T
import java.util.List; qHNE8\9
6)vSG7Ise
import org.flyware.util.page.Page; R
zf
ua5OGx
import net.sf.hibernate.HibernateException; e*bH0'; q
]4R[<<hd
/** q4}PM[K?=\
* @author Joa Qtbbb3m;
*/ Ku\Y'ub
publicinterface UserDAO extends BaseDAO { 0A,]$Fzt
F)s{P Cl
publicList getUserByName(String name)throws w3=%*<
AtF3%Zv2
HibernateException; pGf@z:^{*-
{e+-vl
publicint getUserCount()throws HibernateException; v2H#=E4cZ#
zX0mdx<|<
publicList getUserByPage(Page page)throws uiJS8(Cb
g.'yZvaP
HibernateException;
fv`O4
taFn![}/!g
} s<9RKfm
6oLwfTy
(9<guv
ow0!%|fO
yU8{i&w4
java代码: IkrF/$r
hGbj0
VQ0fS!5'
/*Created on 2005-7-15*/ q EP
4
package com.adt.dao.impl; L0&RvI#
u%]shm
import java.util.List; Y$Q|J4z
y`$Q\}fS
import org.flyware.util.page.Page; FBpH21|/y
l5g$vh\aQ]
import net.sf.hibernate.HibernateException; 1j:Wh
import net.sf.hibernate.Query; *^RmjW1I
MXzVgy
import com.adt.dao.UserDAO; "y_#7K
[5uRS}!
/** A |3tI
* @author Joa G7)Fk%>
*/ HcedE3Rg
public class UserDAOImpl extends BaseDAOHibernateImpl 6_d.Yfbq
wKi^C8Z2
implements UserDAO {
u1z
mwY
IJy[
/* (non-Javadoc) J?Dq>%+^
* @see com.adt.dao.UserDAO#getUserByName K]j0_~3s
,RgB$TcE
(java.lang.String) :^Fh!br==
*/ oyNSh8c7c
publicList getUserByName(String name)throws C_4)=#@GU
+ +aL4:
HibernateException { B*~5)}1op
String querySentence = "FROM user in class NvHJ3> "%
BWrv%7
com.adt.po.User WHERE user.name=:name"; !2z?YZhu
Query query = getSession().createQuery : C b&v07
AgRjr"hF*e
(querySentence); 1fo
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query.setParameter("name", name); IBQ@{QB
return query.list(); +&Hr4@pgW
} jMbC Y07v
o$[z],RO
/* (non-Javadoc) !!4Qj
* @see com.adt.dao.UserDAO#getUserCount() V^hE}`>z&
*/ ZVbl88,(l
publicint getUserCount()throws HibernateException { e]T`ot#/
int count = 0; C=s1R;"H
String querySentence = "SELECT count(*) FROM p|Q*5TO
!<UJ6t}
user in class com.adt.po.User"; 7C$
5
Query query = getSession().createQuery cZ(elZ0~
0b/ WpP
(querySentence); "H&"(=
count = ((Integer)query.iterate().next j:}D Bk
t\RF=BbJJ
()).intValue(); B%KG3]
return count; 6<N5_1
} ?W(6
K]U;?h&CZc
/* (non-Javadoc) M.nvB)
* @see com.adt.dao.UserDAO#getUserByPage 4n
%?YQ[t
kKPi:G52F
(org.flyware.util.page.Page) W`"uu.~f
*/ +uBLk0/)>
publicList getUserByPage(Page page)throws 2_ :n
P\]B<
HibernateException { r}0\}~'?c
String querySentence = "FROM user in class $t5V=}m>
P
i Fm|
com.adt.po.User"; Fbu5PWhlc
Query query = getSession().createQuery RN)dS>$
3SSm5{197
(querySentence); 4;HJ;0-ps
query.setFirstResult(page.getBeginIndex()) dB+N\HBY
.setMaxResults(page.getEveryPage()); n!')wIk
return query.list(); 5C"QE8R o
} <5G{"U+ \
.`7cBsXH
} d/}SAvtt
8/t$d#xHI
h'$QC )P
rJa$9B*^
"+zCS|
至此,一个完整的分页程序完成。前台的只需要调用 xil[#W]7Ge
9}c8Xt^&