Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 vp9E}ga
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 U%SNROj
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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 y|2g"J
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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 R.n`R|NOd
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分页支持类: ROI$;B(
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java代码: `:^)"#z)
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package com.javaeye.common.util; I?xhak1)lu
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import java.util.List; &opH\wa
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publicclass PaginationSupport { ;-P:$zw9c
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publicfinalstaticint PAGESIZE = 30; vA $BBXX
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privateint pageSize = PAGESIZE; jind!@}!
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privateList items; ?)ZLxLV::
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privateint totalCount; k?_$h<Y
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privateint[] indexes = newint[0]; MJk:s[o
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privateint startIndex = 0; <MDFfnj
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public PaginationSupport(List items, int >5YYij5Aj
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totalCount){ @zpHemdB
setPageSize(PAGESIZE); m0K2 p~
setTotalCount(totalCount); uc
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setItems(items); ieK'<%dxF
setStartIndex(0); ]&%X(jWyn
} pz z`4VS:
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public PaginationSupport(List items, int sRI=TE]s
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totalCount, int startIndex){ l[OQo|_
setPageSize(PAGESIZE); )I1V2k$n
setTotalCount(totalCount); m+JGe5fR<
setItems(items); :y)&kJpleP
setStartIndex(startIndex); tLGwF3e$A
} 75cr!+
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public PaginationSupport(List items, int Ymh2qGcj]8
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totalCount, int pageSize, int startIndex){ :j!_XMyT:
setPageSize(pageSize); wz2)seZY
setTotalCount(totalCount); Lzb [%?
setItems(items); DL/*t.)"et
setStartIndex(startIndex); >!WBlSy
} !EC\1rmdlN
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publicList getItems(){ gbi~!S-
return items; *xX0]{49q
} X([n>w
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publicvoid setItems(List items){ n@8{FoF
this.items = items; qv >(
} !!Gi.VL
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publicint getPageSize(){ v?iH}7zb%Q
return pageSize; CX(yrP6;
} `E%d$
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publicvoid setPageSize(int pageSize){ ^.aEKr
this.pageSize = pageSize; oHGf |
} <UHf7:0V
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publicint getTotalCount(){ iY`7\/H!L
return totalCount; =(uy':Dbn*
} 1 jd=R7
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publicvoid setTotalCount(int totalCount){ ;R>42
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if(totalCount > 0){ |zegnq~
this.totalCount = totalCount; !)1Zp*
int count = totalCount / >@\?\!Go
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pageSize; ^C#bW<T
if(totalCount % pageSize > 0) *fyEw\`a
count++; P=hf/jOv9
indexes = newint[count]; gf8U &;
for(int i = 0; i < count; i++){ PbC>v
indexes = pageSize * YV+dUvz
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} )Syf5I
}else{ G\+MT(&5
this.totalCount = 0; [1X5r<(W5
} ]uXsl0'`V
} Ho*RLVI0U
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publicint[] getIndexes(){ \{^yB4F_Z
return indexes; }tg n1xpx
} `RLrT34
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publicvoid setIndexes(int[] indexes){ Al;oI3
this.indexes = indexes; G~j<I/)"
} omU)hFvyS
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publicint getStartIndex(){ m.X+sP-e
return startIndex; jtJ8r5j 1
} `Y$5g~3.
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publicvoid setStartIndex(int startIndex){ -s84/E4Y*
if(totalCount <= 0) /1@m#ZxA:
this.startIndex = 0; mhSsOmJ5
elseif(startIndex >= totalCount) vWga>IGM
this.startIndex = indexes LU=)\U@Q
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[indexes.length - 1]; Z1}zf(JU
elseif(startIndex < 0) ooxzM `
this.startIndex = 0; _^A
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else{ _Pm}]Y:_
this.startIndex = indexes `^Sq>R!;
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[startIndex / pageSize]; soCHwiE
} =5#Jsn?U
} ~&jCz4M
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publicint getNextIndex(){ "C|l3X'
int nextIndex = getStartIndex() + G+p>39P
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pageSize; s$G8`$+i1
if(nextIndex >= totalCount) OlFn<:V K
return getStartIndex(); jv^L~<u
else .DsYR/
return nextIndex; K?I&,t_*R
} ~n\ea:.
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publicint getPreviousIndex(){ ^@> Qiy
int previousIndex = getStartIndex() - +Ea XS
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pageSize; )o,0aGo>Of
if(previousIndex < 0) @=1``z#
return0; }Elce}
else 1#uw^{n
return previousIndex; ^!tI+F{n{
} xz'd5 re%
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} U /Fomu
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抽象业务类 J8'zvH&I
java代码: m@?e
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/** e8v=n@0
* Created on 2005-7-12 p$<qT^]&
*/ a^,RbV/
package com.javaeye.common.business; }A^,y
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import java.io.Serializable; |0mI3r
import java.util.List; _J!mhUA
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import org.hibernate.Criteria; &9{BuBO[
import org.hibernate.HibernateException; ,:{+
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import org.hibernate.Session; EC/R|\d?Un
import org.hibernate.criterion.DetachedCriteria; xnOlV
import org.hibernate.criterion.Projections; [J
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import u&bU !ZI
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org.springframework.orm.hibernate3.HibernateCallback; 55\mQ|.Jn
import :Aw VeX@
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org.springframework.orm.hibernate3.support.HibernateDaoS EUqG"h5#A{
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upport; j&5Xjl>4
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import com.javaeye.common.util.PaginationSupport; //|Vj | =
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public abstract class AbstractManager extends 2T9Z{v
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HibernateDaoSupport { N5DS-gv
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privateboolean cacheQueries = false; o5uwa{v
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privateString queryCacheRegion; |zKcL3*
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publicvoid setCacheQueries(boolean %#~Wk|8} Q
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cacheQueries){ 5JXLfYTUI
this.cacheQueries = cacheQueries; (WvA9s{/
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publicvoid setQueryCacheRegion(String ><~hOK?v
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queryCacheRegion){ w0iEx1i
this.queryCacheRegion = \\JXY*DA:+
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queryCacheRegion; {'%=tJ[YX
} TF>F7v(,45
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publicvoid save(finalObject entity){ v#xF;@G
getHibernateTemplate().save(entity); om6R/K
} , fn=%tiUk
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publicvoid persist(finalObject entity){ RU=%yk-gM
getHibernateTemplate().save(entity); &3V4~L1aEg
} g,nE iL
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publicvoid update(finalObject entity){ 2Z~ofrj
getHibernateTemplate().update(entity); 6%-2G@6d
} ,")7uMZaF\
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publicvoid delete(finalObject entity){ C'ZU .Y
getHibernateTemplate().delete(entity); {YFru6$
} ||f4f3R'
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publicObject load(finalClass entity, U' Cp3>
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finalSerializable id){ x&
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return getHibernateTemplate().load {$^|^n5j
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(entity, id); mD!imq%=
} _ sd?l
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publicObject get(finalClass entity, `0D+x
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finalSerializable id){ 6c :$[owC
return getHibernateTemplate().get {+;8dtZ)x
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(entity, id); tR3hbL$W
} a$
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publicList findAll(finalClass entity){ <9"i_d%
return getHibernateTemplate().find("from CJ_B.
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" + entity.getName()); W3b\LnUa
} ~X/T6(n$
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publicList findByNamedQuery(finalString `*]r.u0
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namedQuery){ ^:BRbp37i
return getHibernateTemplate \MU4"sXw
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().findByNamedQuery(namedQuery); L<:ya
} dx^3(#B
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publicList findByNamedQuery(finalString query, 4?Io@[7A)
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finalObject parameter){ I ;_.tG
return getHibernateTemplate Nn$$yUkMX
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().findByNamedQuery(query, parameter); 0pQ>V)
} 5Ai
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publicList findByNamedQuery(finalString query, B?jF1F!9
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finalObject[] parameters){ k(MQ:9'|
return getHibernateTemplate &>-Cz%IV
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().findByNamedQuery(query, parameters); $jHL8r\e7
} SNQ+ XtoO
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publicList find(finalString query){ &+\wYa,
return getHibernateTemplate().find ;(XSw%Y
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(query); =Zj9F1E[i
} X_h+\
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publicList find(finalString query, finalObject thh, V
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parameter){ [-l^,,E
return getHibernateTemplate().find ,GK>|gNsb
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(query, parameter); ]SQ_*$`
} VAq:q8(K
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public PaginationSupport findPageByCriteria oR+Fn}mG
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(final DetachedCriteria detachedCriteria){ KT3[{lr
return findPageByCriteria j1BYSfX'
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); eA!aUu
} H:|yu
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public PaginationSupport findPageByCriteria 3}"VUS0wh
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(final DetachedCriteria detachedCriteria, finalint h.67]U7m
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startIndex){ c6e?)(V>
return findPageByCriteria X3nwA#If1
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(detachedCriteria, PaginationSupport.PAGESIZE, 2-$R@
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startIndex); 2W}RXqV<
} 7B'0(70
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public PaginationSupport findPageByCriteria "MyYu}AD
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(final DetachedCriteria detachedCriteria, finalint 7QQnvoP
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pageSize, pM>.z9
finalint startIndex){ 2+|[e_
return(PaginationSupport) 6ds&n#n
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getHibernateTemplate().execute(new HibernateCallback(){ QII>XJ9
publicObject doInHibernate [ P
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(Session session)throws HibernateException { WhkE&7Gk
Criteria criteria = +jHL==W&
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detachedCriteria.getExecutableCriteria(session); M,l
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int totalCount = 9;:Lf
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((Integer) criteria.setProjection(Projections.rowCount r>
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()).uniqueResult()).intValue(); HbCM{A9
criteria.setProjection r=s7be
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(null); |`,%%p|T%
List items = f9;M"Pd
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criteria.setFirstResult(startIndex).setMaxResults uHy^ Bq
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(pageSize).list(); dD#A.C,Rz
PaginationSupport ps = 3Y>!e#
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new PaginationSupport(items, totalCount, pageSize, d
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startIndex); ).xQ~A\.
return ps; v\Q${6kEtx
} SC'fT!
}, true); !sUo+Y
} S_C+1e
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public List findAllByCriteria(final K4y4!zz
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DetachedCriteria detachedCriteria){ {gzL}KL
return(List) getHibernateTemplate EWbFy"=
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().execute(new HibernateCallback(){ &g|-3)A
publicObject doInHibernate {D$#m
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(Session session)throws HibernateException { R\)pW9)
Criteria criteria = |[C3_'X
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detachedCriteria.getExecutableCriteria(session); z0a=A:+/
return criteria.list(); F $B_;G
} cu.f]'
}, true); 9FK%"s`
} xoPpu
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public int getCountByCriteria(final jeC3}BL}
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DetachedCriteria detachedCriteria){ vTN$SgzfCU
Integer count = (Integer) 8IbHDDS
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getHibernateTemplate().execute(new HibernateCallback(){ v 6Tz7
publicObject doInHibernate !\2Xr{f
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(Session session)throws HibernateException { ~`(#sjr6KR
Criteria criteria = 9tWu>keu
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detachedCriteria.getExecutableCriteria(session); L3,p8-d9Z
return j$siCsF
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criteria.setProjection(Projections.rowCount Y0
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()).uniqueResult(); b v~"_)C
} P;{f+I|`
}, true); p8frSrcU
return count.intValue(); *ax$R6a#X
} V~ %!-7?
} c&J,O1){\
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用户在web层构造查询条件detachedCriteria,和可选的 V`m'r+ Y
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 ZXh6Se4o
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PaginationSupport的实例ps。 UW_fn
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ps.getItems()得到已分页好的结果集 1!~=8FTv
ps.getIndexes()得到分页索引的数组 @))PpE`co8
ps.getTotalCount()得到总结果数 qlNK }
ps.getStartIndex()当前分页索引 \x5b=~/
ps.getNextIndex()下一页索引 B;@7
ps.getPreviousIndex()上一页索引 fczId"
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 buu~#m1z
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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 9(V12gn+lk
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一下代码重构了。 h(l4\)
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我把原本我的做法也提供出来供大家讨论吧: f.-b.nNf
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首先,为了实现分页查询,我封装了一个Page类: 7j| ^ZuI+
java代码: * G!C 'w\$
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/*Created on 2005-4-14*/ "N>~]
package org.flyware.util.page; rozp
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/** 4i|yEf
* @author Joa LVP2jTz
* 4+"2K-]
*/ wc`UcGO
publicclass Page { nLicog)!I
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/** imply if the page has previous page */ ROsR;C0!
privateboolean hasPrePage; I7,5ID4pn
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/** imply if the page has next page */ 3 }~.#`QeY
privateboolean hasNextPage; wrI66R}@
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/** the number of every page */ cBZ$$$v\#
privateint everyPage; pY]T32
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/** the total page number */ kCRfO}wt3
privateint totalPage; (dmLEt
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