Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 6cTd
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 hv9k9i7@l
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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 e/y\P&"eI
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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 E3 aj
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分页支持类: M>|R&v
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java代码: ,&rHBNS
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package com.javaeye.common.util; c>yqq'
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import java.util.List; U<.,"`=l
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publicclass PaginationSupport { ])$Rw$`w
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publicfinalstaticint PAGESIZE = 30; t(5PKD#~Dc
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privateint pageSize = PAGESIZE; 6,Y<1b*|Vo
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privateList items; <P1x3
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privateint totalCount; @hj5j;NHK
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privateint[] indexes = newint[0]; {K >}eO:K
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privateint startIndex = 0; *BAR`+;U
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public PaginationSupport(List items, int NKE,}^C
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totalCount){ y-^m
setPageSize(PAGESIZE); PuGc{kt
setTotalCount(totalCount); s(shgI 3g
setItems(items); ~)IiF.I b
setStartIndex(0); +:#UU;W
} nx'Yevi0$
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public PaginationSupport(List items, int m}o4Vr;"
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totalCount, int startIndex){ &u~#bDh
setPageSize(PAGESIZE); clO9l=g
setTotalCount(totalCount); h!q_''*;
setItems(items); $ {5|{`
setStartIndex(startIndex); !ui:0_
}
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public PaginationSupport(List items, int /{*0
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totalCount, int pageSize, int startIndex){ [7@9wa1v!
setPageSize(pageSize); bz\-%$^k
setTotalCount(totalCount); )lDmYt7me
setItems(items); F*j0o
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setStartIndex(startIndex); Ee 15Y$1
} (bo-JOOdY(
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publicList getItems(){ Eu1t*>ZL
return items; <X~P62<
} \O(~:KN
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publicvoid setItems(List items){ PQA}_o
this.items = items; k*uLjU
} 6Dz N.fz
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publicint getPageSize(){ u5E\wRn
return pageSize; t @vb3
} P&}J(;Lbl
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publicvoid setPageSize(int pageSize){ ?$Jj^/luD
this.pageSize = pageSize; RA$q{$arb
} VFLW@
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publicint getTotalCount(){ mo
return totalCount; w
} ^M~Z_CQL2
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publicvoid setTotalCount(int totalCount){
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if(totalCount > 0){ '4]_~?&x
this.totalCount = totalCount; F0]xc
int count = totalCount / LMTz/M
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pageSize; d_aHUmI^"
if(totalCount % pageSize > 0) $s"{C"4q
count++; } za"rU
indexes = newint[count]; c=#V*<
for(int i = 0; i < count; i++){ :oO
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indexes = pageSize * "1|\V.>>;
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} =]m,7 v Rq
}else{ EUjA-L(
this.totalCount = 0; jSd[
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} TAp8x
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publicint[] getIndexes(){ jU0E=;1
return indexes; Q7 @oAeNd
} fF]w[lLDv
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publicvoid setIndexes(int[] indexes){ @M&qH[tK-A
this.indexes = indexes; N977F$Bo
} "xV0$%
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publicint getStartIndex(){ nR`)kORc
return startIndex; Df5!z \dx
} B&>z&!}
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publicvoid setStartIndex(int startIndex){ nN5fP<H2x
if(totalCount <= 0) o9]i
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this.startIndex = 0; "< })X.t
elseif(startIndex >= totalCount) 8T?D#,/
this.startIndex = indexes CWa~~h<r-
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[indexes.length - 1]; _bn
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elseif(startIndex < 0) 9>9,
this.startIndex = 0; yV?qX\~*
else{ K7c[bhi_w
this.startIndex = indexes j06qr\Es
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[startIndex / pageSize]; XJe}^k
} 2KtK.2; 7
} TXo`P_SE
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publicint getNextIndex(){ YDYN#Ob(;
int nextIndex = getStartIndex() + l!mx,O`
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pageSize; 8F9x2CM-[C
if(nextIndex >= totalCount) $0XR<D
return getStartIndex(); wDDNB1_E
else NOFuX9/'w
return nextIndex; #7['M;_
} `!Yd$=*c_&
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publicint getPreviousIndex(){ eI,H
int previousIndex = getStartIndex() - 2{<o1x,Ym
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pageSize; l1vI
if(previousIndex < 0) DR7 JEE
return0; K.Tob,5`
else i
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return previousIndex; >!Dp'6
} JFFluL=-
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} nzU;Bi^m
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抽象业务类 H3LuRGe&2
java代码: HZqk)sN
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/** +w/B3b
* Created on 2005-7-12 i>O8q%BnJ
*/ Xo$SQ0K
package com.javaeye.common.business; mDx=n.lIz
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import java.io.Serializable; $plqk^P
import java.util.List; {2 k]$|
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import org.hibernate.Criteria; dhjX[7Bl9
import org.hibernate.HibernateException; WK0:3q(P
import org.hibernate.Session; E0AbVa.
import org.hibernate.criterion.DetachedCriteria; _y&XFdp
import org.hibernate.criterion.Projections; cn: L]%<
import 0S96x}]J B
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org.springframework.orm.hibernate3.HibernateCallback; [*M':
import hn~btu9h
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org.springframework.orm.hibernate3.support.HibernateDaoS V!l?FOSZ
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upport; 6j!idA!'
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import com.javaeye.common.util.PaginationSupport; D?=4'"@v
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public abstract class AbstractManager extends ..zX
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HibernateDaoSupport { 5'( T*"
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privateboolean cacheQueries = false; QQHQ3\
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privateString queryCacheRegion; ZZ L@UO>:
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publicvoid setCacheQueries(boolean $6(a6!
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cacheQueries){ ?GlXxx=eV
this.cacheQueries = cacheQueries; Si@6'sw
} N\];{pe>
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publicvoid setQueryCacheRegion(String !C h1q
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queryCacheRegion){ 0'
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this.queryCacheRegion = '4_c;](W
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queryCacheRegion; ~KRS0^
} y+Hz(}4
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publicvoid save(finalObject entity){ 1$+8wDVwad
getHibernateTemplate().save(entity); @+l=R|
} J?EDz,
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publicvoid persist(finalObject entity){ I&m' a
getHibernateTemplate().save(entity); o2'Wu:Y"
} _-3n'i8
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publicvoid update(finalObject entity){ }%z%}V@(&
getHibernateTemplate().update(entity); ;>L8&m)R5
} 0ckmHv
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publicvoid delete(finalObject entity){ hNhEA $X5
getHibernateTemplate().delete(entity); v K[%cA"
} Ctn
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publicObject load(finalClass entity, )P>/g*
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finalSerializable id){ #4lIna%VX
return getHibernateTemplate().load {z\K!=X/
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(entity, id); rwVp}H G
} reNf?7G+m
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publicObject get(finalClass entity, PZ`11#bbm
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finalSerializable id){ #]6{>n1*+w
return getHibernateTemplate().get H%X F~tF:
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(entity, id); E3l*_b0
} ":vEWp+g
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publicList findAll(finalClass entity){ El@*Fo
return getHibernateTemplate().find("from Gw\..O
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" + entity.getName()); NPrLM5
} <e?Eva%t`
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publicList findByNamedQuery(finalString $XTtD UP@
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namedQuery){ WubV?NX;EF
return getHibernateTemplate yW(|auq
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().findByNamedQuery(namedQuery); ~bCA8
} C l,vBjl h
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publicList findByNamedQuery(finalString query, XL^05
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finalObject parameter){ KyfH8Na?
return getHibernateTemplate M:{Aq&.
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().findByNamedQuery(query, parameter); )-emSV0zE
} #XA`n@2Uoo
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publicList findByNamedQuery(finalString query, 9aY8`B
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finalObject[] parameters){ nvT@'y+
return getHibernateTemplate )t"-#$,@
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().findByNamedQuery(query, parameters); L/r_MtN
} &=BzsBh
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publicList find(finalString query){ [#q]B=JB
return getHibernateTemplate().find -PAEJn5$O
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(query); QcW8A ,\q
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publicList find(finalString query, finalObject F{!pii5O9
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parameter){ ,d,2Q
return getHibernateTemplate().find Xs2 jR14`
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(query, parameter); ]5c(:T F
} "mf$E|
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public PaginationSupport findPageByCriteria ESIP+
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(final DetachedCriteria detachedCriteria){ NeG`D'
return findPageByCriteria &<]f-
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); H{vKk
} lQHF=Jex
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public PaginationSupport findPageByCriteria Ly+UY.v"
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(final DetachedCriteria detachedCriteria, finalint v62_VT2v
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startIndex){ +h4W<YnW
return findPageByCriteria c\1X NPGG
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(detachedCriteria, PaginationSupport.PAGESIZE, n jWe^
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startIndex); WC`h+SC`.
} ?gl&q+mv
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public PaginationSupport findPageByCriteria 0bDc
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(final DetachedCriteria detachedCriteria, finalint oT):#,s
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pageSize, dA~:L`A|X
finalint startIndex){ iVI&
return(PaginationSupport) r
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getHibernateTemplate().execute(new HibernateCallback(){ bGH#s {'5
publicObject doInHibernate gmRc4o
}q.D)'g_
(Session session)throws HibernateException { 5]N0p,f
Criteria criteria = 7@fS2mu
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detachedCriteria.getExecutableCriteria(session); q>.7VN[
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int totalCount = d#rr7O
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((Integer) criteria.setProjection(Projections.rowCount 1@}F8&EZ
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()).uniqueResult()).intValue(); Z^&G9I#
criteria.setProjection ~R
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(null); #T_!-;(Z
List items = '"
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criteria.setFirstResult(startIndex).setMaxResults 9j>2C
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(pageSize).list(); 't5ufAT
PaginationSupport ps = #cfiN b}GX
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new PaginationSupport(items, totalCount, pageSize, 8(%F{&<;
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startIndex); JY#vq'dl|
return ps; X3:z=X&Zd
} ZL6HD n!
}, true); wf\"&xwh?
} cmG27\c RO
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public List findAllByCriteria(final )/$J$'mcxd
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DetachedCriteria detachedCriteria){ ?% 24M\
return(List) getHibernateTemplate .*-8rOcc
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().execute(new HibernateCallback(){ u /F!8#
publicObject doInHibernate 8!{*!|Xd
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(Session session)throws HibernateException { )j36Y =r3
Criteria criteria = f1 x&Fk
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detachedCriteria.getExecutableCriteria(session); JY,$B-l
return criteria.list(); Zd[rn:9\
} _`udd)Y2
}, true); Z!"-LQJ
} U6M~N0)Yr
;
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public int getCountByCriteria(final U#[&(
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DetachedCriteria detachedCriteria){ S;% &X
Integer count = (Integer) D;pI!S<#
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getHibernateTemplate().execute(new HibernateCallback(){ 6nW)2LV
publicObject doInHibernate zr.\7\v
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(Session session)throws HibernateException { H
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Criteria criteria = ~XTC:6ts
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detachedCriteria.getExecutableCriteria(session); /mex{+p>tO
return F06o-xH=
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criteria.setProjection(Projections.rowCount eP-|3$
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()).uniqueResult(); `}Zqmfs
} 'Lrn<
}, true); 7?Wte&C];p
return count.intValue(); #rkq
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} 'C'mgEl%L
} NU=ru/
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用户在web层构造查询条件detachedCriteria,和可选的 kUd]8Ff!
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 su%(!XJQpg
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PaginationSupport的实例ps。 vjS`;^9
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ps.getItems()得到已分页好的结果集 S<0 &V
ps.getIndexes()得到分页索引的数组 eY<<Hld
ps.getTotalCount()得到总结果数 o$No@~%v
ps.getStartIndex()当前分页索引 r2=@1=?8
ps.getNextIndex()下一页索引 )5}<@Ql
ps.getPreviousIndex()上一页索引 V`I4"}M1
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 lFzVd
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,尤其是上面的示例代码,让我着实觉得该对我原来的分页查询做 }DhqzKl
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一下代码重构了。 m;@q('O
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我把原本我的做法也提供出来供大家讨论吧: =
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首先,为了实现分页查询,我封装了一个Page类: ?:"ABkL|+Y
java代码: 6
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/*Created on 2005-4-14*/ rwP#Yj[BK+
package org.flyware.util.page; I"Zp^j
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/** e5'I W__
* @author Joa h4;kjr}h}
* jK w
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*/ G2`z?);1b
publicclass Page { I C
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/** imply if the page has previous page */ FIq'W:q:
privateboolean hasPrePage; *#=Ij r~
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/** imply if the page has next page */ :G _
privateboolean hasNextPage; q'mh*
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/** the number of every page */ o[ 5dR<
privateint everyPage; MmT/J1zM
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/** the total page number */ FZi@h
privateint totalPage; Sm'Tz&!
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/** the number of current page */ -#Z df|
privateint currentPage; ^DYS~I%s
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/** the begin index of the records by the current &;@L]
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query */ _Y; TS1u
privateint beginIndex; cH5i420;aO
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/** The default constructor */ %Ig$: I(o
public Page(){ ]oGd,v X
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} bzi"7%c
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/** construct the page by everyPage s=8H<'l
* @param everyPage & zDuh[j}
* */ f.6>6%l
public Page(int everyPage){ dNe!X0[
this.everyPage = everyPage; iWCYK7c@.-
} )?rq8VO
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/** The whole constructor */ ` Ig5*X4|
public Page(boolean hasPrePage, boolean hasNextPage, FV^jCseZ
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int everyPage, int totalPage, o~LJ+m6-)
int currentPage, int beginIndex){ P $`1}
this.hasPrePage = hasPrePage; a/J<(sak~X
this.hasNextPage = hasNextPage; :c*"Dx'D
this.everyPage = everyPage; 2-4N)q
this.totalPage = totalPage; rq%]CsRY5
this.currentPage = currentPage; zhn?;Fi
this.beginIndex = beginIndex; /oPW0of
} tq
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/** {nmG/dn{
* @return #
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* Returns the beginIndex. lod+]*MD
*/ =KPmZ ,/w
publicint getBeginIndex(){ w"R<8e=
return beginIndex; %-n)L
} Xh"9Bcjf
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/** <F9-$_m
* @param beginIndex Hx#YN*\.M
* The beginIndex to set. ?}HK!feU
*/ j yHa}OT
publicvoid setBeginIndex(int beginIndex){ S!?T0c?>
this.beginIndex = beginIndex; :;%Jm
} BE?]P?r?
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/** /2K"Mpf8
* @return K6v~!iiK$
* Returns the currentPage. I5"wa:Z
*/ ^+(5[z
publicint getCurrentPage(){ %vmd2}dA
return currentPage; A?YYR%o%'
} 3BMz{ny=
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/** j97+'AKX
* @param currentPage ^|/mn!7wD
* The currentPage to set. %1#\LRA(
*/ Y:\msq1xp
publicvoid setCurrentPage(int currentPage){ mEY#QN[eq
this.currentPage = currentPage; pBqf+}g4
} s<