Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 j,j|'7J%
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 h+W$\T)
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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 V?M(exN
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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 A08kwYxiW
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分页支持类: $P{`-Y }a
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java代码: }:2##<"\t
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package com.javaeye.common.util; )h}IZSm
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import java.util.List; T01Iu
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publicclass PaginationSupport { 5sT3|yq
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publicfinalstaticint PAGESIZE = 30; NBPP?\1
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privateint pageSize = PAGESIZE; hoq2zDjD
c& ;@i$X(
privateList items; ..JRtuM-v
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privateint totalCount; aZb\uMePK
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privateint[] indexes = newint[0]; iN&oSpQ
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privateint startIndex = 0; w^0hVrws=,
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public PaginationSupport(List items, int "9_$7.q<y
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totalCount){ Z<;W*6J
setPageSize(PAGESIZE); N
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setTotalCount(totalCount); D&):2F^9.
setItems(items); ?h[HC"V/2
setStartIndex(0); 8%K{l g"
} $U_(e:m}f
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public PaginationSupport(List items, int _Ay^v#a
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totalCount, int startIndex){ rQ.zqr
setPageSize(PAGESIZE); dL$ iTSfz"
setTotalCount(totalCount); ;z4J)qw
setItems(items); 8'*x88+
setStartIndex(startIndex); MDF_Xr-hZ
} O(/~cQ
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public PaginationSupport(List items, int 86{>X5 +
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totalCount, int pageSize, int startIndex){ pWxk^qhe/
setPageSize(pageSize); 0#WN2f, <:
setTotalCount(totalCount); 4:/V|E\D
setItems(items); !.'D"Me>
setStartIndex(startIndex); F1.Xk1y%
} \ivxi<SR
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publicList getItems(){ 9qftMDLZJ\
return items; F%6wdM W
} o-@01_j
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publicvoid setItems(List items){ y$%oR6K7-
this.items = items; 7Y8~")f
} <YW)8J
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publicint getPageSize(){ W4o8]&A
return pageSize; fn,n'E]
} \x-2qlZ
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publicvoid setPageSize(int pageSize){ H0s*Lb
this.pageSize = pageSize; cA Nt7
} cTq@"v di
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publicint getTotalCount(){ 2 q4p-
return totalCount; `$/a-K}
} $bG*f*w
f0H.$UAL
publicvoid setTotalCount(int totalCount){ d}Pfj=W
if(totalCount > 0){ ><}nZ7
this.totalCount = totalCount; 56)!&MF
int count = totalCount / +E</A:|}S
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pageSize; ;y,g%uqE
if(totalCount % pageSize > 0) 3/+kjY/
count++; G Y%5N= u
indexes = newint[count]; v^ ^Ibv
for(int i = 0; i < count; i++){ bW=q G
indexes = pageSize * i9L]h69r
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;
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} Ss%Cf6qdWL
}else{ _-C/sp^
this.totalCount = 0; G*4I;'6
} c
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} wnC} TWxX
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publicint[] getIndexes(){ j{Px}f(=
return indexes; }!_z\'u
} NfClR HpVc
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publicvoid setIndexes(int[] indexes){ ~6;I"0b5
this.indexes = indexes; 3`&FXgo
} D>y5&`
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publicint getStartIndex(){ 8r(awp
return startIndex; "Ol:ni1
} zwV!6xG
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publicvoid setStartIndex(int startIndex){ DP),~8
if(totalCount <= 0) X:UlL"G
this.startIndex = 0; &9flNoNR9
elseif(startIndex >= totalCount) th73eC'
this.startIndex = indexes JH\:9B+:L
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[indexes.length - 1]; 2A\b-;4EP
elseif(startIndex < 0) r<ww%2HTS
this.startIndex = 0; LL
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else{ 71@eJQ
this.startIndex = indexes .jD!+wv{9
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[startIndex / pageSize]; * F%1~
}
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} "|X'qKS(H{
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publicint getNextIndex(){ lNxP
int nextIndex = getStartIndex() + .6`r`|=
[
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pageSize; <OEIG0
if(nextIndex >= totalCount) 4,;*sc 6*
return getStartIndex(); LVg#E*J
else /[_aK0U3
return nextIndex; ]t)N3n6Bc
} 9>4 #I3
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publicint getPreviousIndex(){ Q!q6R^5!K
int previousIndex = getStartIndex() - d'W2I*Zc<
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pageSize; 4"@;.C""
if(previousIndex < 0) ?7NSp2aq2A
return0; UK,bfLPt~
else ?L0;,
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return previousIndex; WkiT,(i
} 6agq^wI
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} gfK_g)'2U
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抽象业务类 >s5}pkAv|e
java代码: =J1V?x=l@
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/** x[lIib1s
* Created on 2005-7-12 "9P @bA
*/ ^5s7mls
package com.javaeye.common.business; lO cFF0'
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import java.io.Serializable; ;+\h$
import java.util.List; b|-)p+ba
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import org.hibernate.Criteria; %j^QK>%
import org.hibernate.HibernateException; @K!JE w\
import org.hibernate.Session; @ovaOX
import org.hibernate.criterion.DetachedCriteria;
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import org.hibernate.criterion.Projections; eHvUgDt
import d2eXN3"
R|*0_!O:[
org.springframework.orm.hibernate3.HibernateCallback; CtMqE+j^
import h
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{v0r'+`
org.springframework.orm.hibernate3.support.HibernateDaoS ]D;*2Lw4&
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upport; ,G0"T~
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import com.javaeye.common.util.PaginationSupport; B{=DnB6
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public abstract class AbstractManager extends J.JD8o9sa
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HibernateDaoSupport { K W&muD
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privateboolean cacheQueries = false; ((`\i=-o5
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privateString queryCacheRegion; ?u#s ?$ Y?
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publicvoid setCacheQueries(boolean |9XoRGgXU
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cacheQueries){ %ud-3u52M8
this.cacheQueries = cacheQueries; =iB[sLEJ
} kk`K;`[tB
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publicvoid setQueryCacheRegion(String lZRO"[<
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queryCacheRegion){ d 8;kM`U
this.queryCacheRegion = itNuY<"
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queryCacheRegion; cEa8l~GC<
} Fy\q>(v.
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publicvoid save(finalObject entity){ xGyl7$J
getHibernateTemplate().save(entity); *bo| F%NAz
} kttJTP77t
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publicvoid persist(finalObject entity){ B`)sc ~u
getHibernateTemplate().save(entity); d:iJUVpr
} w/
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publicvoid update(finalObject entity){ GXm#\)
getHibernateTemplate().update(entity); >"IG\//I
} ym5@SBqIx
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publicvoid delete(finalObject entity){ 5 ph CEKt;
getHibernateTemplate().delete(entity); rZwSo]gp
} (z8ZCyq7r[
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publicObject load(finalClass entity, !i8)si_
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finalSerializable id){ %r.OV_04
return getHibernateTemplate().load &I=o1F2B)
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(entity, id); dH5*%
} hN K wQ
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publicObject get(finalClass entity, HqsqUS3[
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finalSerializable id){ Y [)mHs2
return getHibernateTemplate().get
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(entity, id); u(3 uZ:
} XK\nOHLS
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publicList findAll(finalClass entity){ F|6"-*[RS
return getHibernateTemplate().find("from JtY$AP$
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" + entity.getName()); 9mk@\Gqqm
} 93D}0kp
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publicList findByNamedQuery(finalString DqY"N]
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namedQuery){ @ NDcO,]
return getHibernateTemplate K:-jn}i?/
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().findByNamedQuery(namedQuery); ]:@{tX7c
} 6X9$T11Vc
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publicList findByNamedQuery(finalString query, c
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finalObject parameter){ /,uxj5_cT
return getHibernateTemplate CvRCcSJM\2
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().findByNamedQuery(query, parameter); I 2AQ
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} g&$5!ifgi
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publicList findByNamedQuery(finalString query, q p}2
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finalObject[] parameters){ 1H.;r(c
return getHibernateTemplate ~]no7O4
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().findByNamedQuery(query, parameters); /L2ZI1v
} KM)MUPr
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publicList find(finalString query){ vv)w@A:Vn)
return getHibernateTemplate().find `qd5+~c
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(query); 7hx^U90K
} indbg
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publicList find(finalString query, finalObject < ~CY?
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parameter){ p`&{NR3+
return getHibernateTemplate().find dHOH]x
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(query, parameter); .e5@9G.jb
} BQUYT/$(
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public PaginationSupport findPageByCriteria
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(final DetachedCriteria detachedCriteria){ jQz^)8)B
return findPageByCriteria w=-{njMz6&
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); 9`/ywt3Y
} ;7E"@b,tPN
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public PaginationSupport findPageByCriteria MW^FY4V1m
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(final DetachedCriteria detachedCriteria, finalint $B>L_~cS
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startIndex){ f]2gjQHM
return findPageByCriteria -$%~EY}
9\Rk(dd
(detachedCriteria, PaginationSupport.PAGESIZE, &{WEtaXaa
7 v3%dCvf
startIndex); aB G*
} z,C>Rh9Id
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public PaginationSupport findPageByCriteria 6,CK1j+tZ
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(final DetachedCriteria detachedCriteria, finalint #0*I|gfV
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pageSize, p8F$vx4,
finalint startIndex){ V^.Z&7+E`_
return(PaginationSupport) 2&s(:=
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getHibernateTemplate().execute(new HibernateCallback(){ /Yww G;1
publicObject doInHibernate 26zif
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(Session session)throws HibernateException { M>RLS/r>d
Criteria criteria = 23;\l
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detachedCriteria.getExecutableCriteria(session); Z^A( Q>{e
int totalCount = YE"MtL {
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((Integer) criteria.setProjection(Projections.rowCount A-\n"}4
9<!??'@f
()).uniqueResult()).intValue(); m`XaY J
criteria.setProjection \q-["W34
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(null); TxkvHiq2
List items = 1U~'8=-
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criteria.setFirstResult(startIndex).setMaxResults .b*-GWx
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(pageSize).list(); L(`q3>iC4.
PaginationSupport ps = 6NFLk+kqN
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new PaginationSupport(items, totalCount, pageSize, =o"sBVj
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startIndex); X~; *zYd5
return ps; ;P|v'NNI
} l_q1h]/
}, true); jI}{0LW&F&
} N~yGtnW
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public List findAllByCriteria(final *i7-_pT
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DetachedCriteria detachedCriteria){ P/9|mYmsq
return(List) getHibernateTemplate Mr K?,7*Xi
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().execute(new HibernateCallback(){ ol4!#4Y&{
publicObject doInHibernate b{e|~v6&
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(Session session)throws HibernateException { v}z{OB
Criteria criteria = i6h0_q8
>
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detachedCriteria.getExecutableCriteria(session);
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return criteria.list(); ~Oj-W6-+&,
} +qF,XJ2
}, true); 9VTE?,
} 3o__tU)B
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public int getCountByCriteria(final O~#OVFJ9=
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DetachedCriteria detachedCriteria){ 9c@\-Z'
Integer count = (Integer) TlBu3z'P
}5;3c %
getHibernateTemplate().execute(new HibernateCallback(){ }xzbg
publicObject doInHibernate 0.t1p(x;
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(Session session)throws HibernateException { Uefw
Criteria criteria = obIYC
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detachedCriteria.getExecutableCriteria(session); RE:$c!E!
return Riz!HtyR
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criteria.setProjection(Projections.rowCount 9=^4p=1J
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()).uniqueResult(); </d&bS
} Rh#TR"
}, true); X=OJgyO/
return count.intValue(); ~rU{Q>c
} (svd~h e2
} Os7 3u#!'
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用户在web层构造查询条件detachedCriteria,和可选的 S)\%.~ n
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 cS1BB#N0
*[_>d.i
PaginationSupport的实例ps。 eqE%ofW
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ps.getItems()得到已分页好的结果集 gobqS+c
ps.getIndexes()得到分页索引的数组 Z66@@?`
ps.getTotalCount()得到总结果数 S}*%l)vfR
ps.getStartIndex()当前分页索引 @=[SsS
ps.getNextIndex()下一页索引 )TcW.d6
ps.getPreviousIndex()上一页索引 $r=Ud >
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 9f4#b8
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,尤其是上面的示例代码,让我着实觉得该对我原来的分页查询做 u{ .UZTn
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一下代码重构了。 7MT[fA8^
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我把原本我的做法也提供出来供大家讨论吧: }A"%YDrNbG
LJMw-#61sj
首先,为了实现分页查询,我封装了一个Page类: }0Q6iHX@
java代码: 1vQj` F
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/*Created on 2005-4-14*/ BI] %$rq
package org.flyware.util.page; K G~fDb
{
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/** &?<o692
* @author Joa i=<N4Vx
* b&Sk./
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*/ bg)yliX
publicclass Page { 9c1n
DP NUm<>
/** imply if the page has previous page */ XoaB X2
privateboolean hasPrePage; f&Bu_r
of^N4
/** imply if the page has next page */ ;
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privateboolean hasNextPage; )*iSN*T8q
jn#
/** the number of every page */ <5~} !N X`
privateint everyPage; Ee##:I[z
X] /r'Tz
/** the total page number */ s Hu~;)
privateint totalPage; 4PEJ}BW
7oDr`=q1]r
/** the number of current page */ e}e\*BL
privateint currentPage; HzT"{N9
J~:/,'Ea
/** the begin index of the records by the current mYN|)QVKy
Cj}1 )qWq
query */ @W^A%6"j
privateint beginIndex; 6;GL>))'
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INrUvD/*
/** The default constructor */ D;|4ZjM-
public Page(){ swnov[0
h"')D
} !G#3jh:kiY
J+LFzl07q
/** construct the page by everyPage ]v 6u
* @param everyPage cv0}_<Tyx
* */ g/4.^c
public Page(int everyPage){ K{HRjNda#
this.everyPage = everyPage; d7u"Z5t
} h?DMrYk_%#
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/** The whole constructor */ Ajhrsa\~a
public Page(boolean hasPrePage, boolean hasNextPage, g Bq, So
8lt P)K4
2|#3rF
int everyPage, int totalPage, ue$\i =jw
int currentPage, int beginIndex){ .Lp0_R@
this.hasPrePage = hasPrePage; LeY\{w
this.hasNextPage = hasNextPage; HT5G HkT
this.everyPage = everyPage; ])a?ri
this.totalPage = totalPage; ]RQQg,|D
this.currentPage = currentPage; }yU,_:
this.beginIndex = beginIndex; /"Om-DK%
} h8O[xca/~
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9
/** LC\Ys\/,U
* @return |9!3{3
* Returns the beginIndex. <Dt,FWWkv'
*/ s0.yPA
publicint getBeginIndex(){ Hi9 ;i/
return beginIndex; RIM"MR9qe=
} |]]Xee]
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/** C 9,p-
* @param beginIndex vu YH+
* The beginIndex to set. u/cL[_Q
*/ ^&DHBx"J
publicvoid setBeginIndex(int beginIndex){ %n9}P ,
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this.beginIndex = beginIndex; *#frbV?;
} p(~>u'c
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/** ho@f}4jhQ3
* @return ALwkX"AN
* Returns the currentPage. *n2Q_o
*/ yIbz\3
publicint getCurrentPage(){ M0 x5s@
return currentPage; o
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} sN7I~
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/** 'sY>(D*CQ
* @param currentPage ^,b*.6t
* The currentPage to set. T8ZBQ;o
*/ FymA_Eq
publicvoid setCurrentPage(int currentPage){ OgS6#X
this.currentPage = currentPage; VE6T&fz`
} yK0Q,
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/** 5}~*,_J2Z
* @return oFHVA!lqe
* Returns the everyPage. 9ToM5oQ
*/ J~DP*}~XK
publicint getEveryPage(){ 7~eo^/PbS
return everyPage; -^$CGRE6A
} bP Er+?fu
*
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/** 23y7l=.b/
* @param everyPage djPr 4Nog
* The everyPage to set. v(=fV/
*/ rc*&K#? B
publicvoid setEveryPage(int everyPage){ RV^2[Gdi
this.everyPage = everyPage; 4G@vO{$
} zY\v|l<T
_1dG!!L_
/** Yiu)0\ o
* @return Q9 kKk
* Returns the hasNextPage. A`=ESz
*/ 27E6S)zv
publicboolean getHasNextPage(){ p2!x8`IB*
return hasNextPage; -deY,%
} -d%bc?
H<%7aOwO2
/** M[R, m_p
* @param hasNextPage S]9:3~
* The hasNextPage to set. phbdV8$L
*/ t_3)}
publicvoid setHasNextPage(boolean hasNextPage){ zScV 9,H1
this.hasNextPage = hasNextPage; h^~eTi;c]Q
} \ H<'W"
)(\5Wk9(
/** A,lcR:@w
* @return QXq~e
* Returns the hasPrePage. 8:$kFy\A'
*/ Q2^}NQO=
publicboolean getHasPrePage(){ M$%aX,nk'
return hasPrePage; vjZX8KAiZ
} EiP_V&\
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/** _myam3[W
* @param hasPrePage !;'U5[}8
* The hasPrePage to set. EZIMp8^
*/ cpFw]w%]
publicvoid setHasPrePage(boolean hasPrePage){ kdQ=%
this.hasPrePage = hasPrePage; E^1uZI\z
} RX=C)q2c
!F;W#Gc
/** 0$}+tq+
* @return Returns the totalPage. uc=-+*D'I
* 0l.+yr}PE
*/ -q(,}/Xf
publicint getTotalPage(){ @XDU!<N
return totalPage; 5^GUuFt5m
} H=Yl
@
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/** u+[ZWhKUp
* @param totalPage rA8neO)
* The totalPage to set. =
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*/ ^z9ITGB~tV
publicvoid setTotalPage(int totalPage){ 2p@Rr7
this.totalPage = totalPage; Qgo0uuM
} lx U}HM
}v0oFY$u`H
} c(ZkK
(
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`"zX<
eO(VSjo'`
@5acTYQ
上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 9!_`HE+(XJ
cpgHF`nt
个PageUtil,负责对Page对象进行构造: lb{*,S
java代码: T"in
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/*Created on 2005-4-14*/ 22}J.'Zb
package org.flyware.util.page; .9lx@6]+
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import org.apache.commons.logging.Log; Rw^4S@~T
import org.apache.commons.logging.LogFactory; '2uQ
`-]*Qb+
/** f@[q# }6
* @author Joa ]*%0CDY6`N
* wcsUb9(
*/ 'Xxt[Jy
publicclass PageUtil { ,hT t]w
KNQX\-=
privatestaticfinal Log logger = LogFactory.getLog -zN*2T
QI=",vmau
(PageUtil.class); SD8Q_[rY
V. =! ^0'A
/** ;[ pyKh
* Use the origin page to create a new page &=<x&4H+
* @param page (gvaYKvr
* @param totalRecords "CT'^d+
* @return fg*IHha
*/ p r(:99~3
publicstatic Page createPage(Page page, int 1 c3gHc7{t
K> lA6i7?
totalRecords){ %^2LTK(P
return createPage(page.getEveryPage(), ^7Z)/c`"
jU@qQ@|
page.getCurrentPage(), totalRecords); #J)sz,)(
} ,m8l
/wG
zp!{u{
/** v'`C16&^]
* the basic page utils not including exception deQ0)A 4g
@4sv(HyDY
handler (05/}PhB`
* @param everyPage 2%. A{!
* @param currentPage oa}-=hG
* @param totalRecords A=I]1r
* @return page }_@*,
*/ 9=ns.r
publicstatic Page createPage(int everyPage, int Xb?P'nD
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currentPage, int totalRecords){ Eu l,1yR
everyPage = getEveryPage(everyPage); (6^v`SZ
currentPage = getCurrentPage(currentPage); ,=Xr'7w,
int beginIndex = getBeginIndex(everyPage, ">v76%>Z7
eL0U5>#
currentPage); ht(RX
int totalPage = getTotalPage(everyPage, *_!nil 3(i
pTprU)sa7
totalRecords); [_G_Wl'#8
boolean hasNextPage = hasNextPage(currentPage, aiF7\^aw$
-ce N}Cb3
totalPage); .Quu_S_vH
boolean hasPrePage = hasPrePage(currentPage); i,8h
B(M!
;8'hvc3i$
returnnew Page(hasPrePage, hasNextPage, =;l.<{<VH
everyPage, totalPage, /[q6"R!uMz
currentPage, z{]$WVs:^
b" 1a7
beginIndex); }cn46L%/
} V\W?@V9g-
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privatestaticint getEveryPage(int everyPage){ kl?U2A.=
return everyPage == 0 ? 10 : everyPage; SGXXv
} f<=<:+
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privatestaticint getCurrentPage(int currentPage){ %\6|fKB4<
return currentPage == 0 ? 1 : currentPage; :rk=(=@8`
} fINF;TK
qg7.E+
privatestaticint getBeginIndex(int everyPage, int ZNuz%VO
-+Axa[,5=
currentPage){ 9y{[@KG
return(currentPage - 1) * everyPage; =3]}87
} F=7X,hK
6NPCp/
privatestaticint getTotalPage(int everyPage, int MCZTeYnx
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totalRecords){ jV2L;APCq
int totalPage = 0; 6}6;%{p"Gu
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'8
if(totalRecords % everyPage == 0) IDQ@h`"B
totalPage = totalRecords / everyPage; qjFz}6
else 8UJK]_99I,
totalPage = totalRecords / everyPage + 1 ; q_bE?j{
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return totalPage; .vE=527g)
} 9t:F![rg
A'vQtlvKA
privatestaticboolean hasPrePage(int currentPage){ ;IZ*o<_
return currentPage == 1 ? false : true; VgD z:j
} ,m;S-Im_Xr
Jr$,w7tQn@
privatestaticboolean hasNextPage(int currentPage, PIR#M('
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int totalPage){ O-J;iX }
return currentPage == totalPage || totalPage == b`){f\#t
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0 ? false : true; 5\gL+qM0
} GqMa|8j
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} ?oana%
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m5m}RWZ#
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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。 O=~8+sa
ZKy)F-yX
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 s~
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nr7#}pzo
做法如下: Yv<'QC
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 ]L+YnZ?6
PP)iw@9j
的信息,和一个结果集List: RfH.WXi
java代码: ~QgyhJM_h=
TRP#b 7nC
,5!&}
/*Created on 2005-6-13*/ +`tl<rg;
package com.adt.bo; i[_(0P+Da
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import java.util.List; 5.m&93P
}<R,)ZV^G
import org.flyware.util.page.Page; R=
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/** w0qrh\3du
* @author Joa `EKmp|B_p_
*/ G &,1 NjSi
publicclass Result { b3R1L|@
I> <B6pIR
private Page page; G"k.sRKu
ha[c<e]uo[
private List content; jf&B5>-x
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/** DrI"YX
* The default constructor nhV\<
*/ Vw-,G7v&E
public Result(){ Yc~(Wue
super(); loRT+u$&
} H<_BnT#
dbn9t7'{
/** ` 9;0Y
* The constructor using fields LLy w9y1
* %+ln_lgD:
* @param page aa|u*afWQ
* @param content UWU(6J|Fk
*/ q4u,pm,@
public Result(Page page, List content){ m=Mb'<
this.page = page; 5OEo(&
this.content = content; a8 X}r.
} e"}JHXs
b a5,?FVI~
/** AWaptw_p*
* @return Returns the content. /{1s U}k-
*/ &T.d"i
publicList getContent(){ A]0A,A0
return content; &10l80vj
} M3XG s|gw
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/** w8=&rzr8
* @return Returns the page. Vn&{yCm3
*/ cp1-eR_&
public Page getPage(){ /80H.|8O
return page; ]MD,{T9l\>
} zM+4<k_dH]
Sg%h}]~
/** pbCj
^
* @param content { 6
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* The content to set. -VZn`6%s
*/ DWv(|gO
public void setContent(List content){ /esdtH$=
this.content = content; oW}nr<G{<
} )Ehi8
LN z
/** su$IXI#R-&
* @param page .7K)'
* The page to set. In[rxT~K}Q
*/ BiY-u/bH9a
publicvoid setPage(Page page){ dU}Cb?]7s
this.page = page; m+UWvUB)
} G2$<Q+UYs?
} jz,K>
QhhL_vP
GB%kxtGD;\
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n;@.eC,T/
2. 编写业务逻辑接口,并实现它(UserManager, oACbZ#/@n
6|mHu2qXm
UserManagerImpl) sLKk1A
java代码: ,`Keqfx
e{EC#%x_
kzE<Y
/*Created on 2005-7-15*/ V`
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package com.adt.service; LC1WVK/
zqHG2:MN"
import net.sf.hibernate.HibernateException; OV
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^4b;rLfk@
import org.flyware.util.page.Page; -9]
ucmN
ZUyS+60
import com.adt.bo.Result; z*a-=w0
z@g%9|U
/** -uKTEG[
* @author Joa Ypx5:gm|J
*/ 0OXl`V`w
publicinterface UserManager { nt&"?
/s
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public Result listUser(Page page)throws YdZ9##IU3
y
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HibernateException; ?gsPHP US
j.&Y'C7GOC
} KuRJo]
/7 8zs-
;J@U){R
KqN;a i,F
4U8N7
java代码: )x,/+R]{8l
2tb+3K1
u`.3\Geh
/*Created on 2005-7-15*/ SK5_^4
package com.adt.service.impl; hgj ]Jr
D6dliU?k
import java.util.List; Z2U6<4?1%
(@ 1>G
^%
import net.sf.hibernate.HibernateException; BM~6P|&qD
X"jL
import org.flyware.util.page.Page; ECyG$j0
import org.flyware.util.page.PageUtil; _l"=#i@L
rB|1<jR
import com.adt.bo.Result; pO/vD~C>
import com.adt.dao.UserDAO; fN1b+d~*6
import com.adt.exception.ObjectNotFoundException; /-knqv
import com.adt.service.UserManager; 6HguZ_jC
soRYM
/** DfU]+;AE
* @author Joa x5Ue"RMl+
*/ :GN++\1pw
publicclass UserManagerImpl implements UserManager { Z2L7US-
MQQQaD:v
private UserDAO userDAO; NEUr w/
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/** K'}I?H~P_
* @param userDAO The userDAO to set. 2,Aw6h;
*/ U(PW$\l
publicvoid setUserDAO(UserDAO userDAO){ oTRidG
this.userDAO = userDAO; A0>r]<y
} W}y)vrL
c1q;
/* (non-Javadoc) Gshy$'_e
* @see com.adt.service.UserManager#listUser m68>`
a/v]E]=qI
(org.flyware.util.page.Page) E/hT/BOPK
*/ cij8'("+!
public Result listUser(Page page)throws x=Aq5*A0
Kx?.g#>U;
HibernateException, ObjectNotFoundException { ]%ewxF
int totalRecords = userDAO.getUserCount(); 9[`c"Pd
if(totalRecords == 0) ]WzeJ"r {3
throw new ObjectNotFoundException ^9`|QF
o[1#)&
("userNotExist"); +!GJ
page = PageUtil.createPage(page, totalRecords); gKY6S?
List users = userDAO.getUserByPage(page); g${JdxR:
returnnew Result(page, users); #sg*GK+|:R
} kdWUz(
S[gACEZ =
} @eZBwFe
1{5t.
"hQGk
hj&~Dn(
f ~*7hv\
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 Y]*&\Ex"\
A|,qjiEJCc
询,接下来编写UserDAO的代码: @ze2'56F}
3. UserDAO 和 UserDAOImpl: Q lA?dXQ
java代码: 5HsF#
J>k
6`gw
aNs8T`
/*Created on 2005-7-15*/ j74hWz+p4
package com.adt.dao; Q% d1O
J2 / 19'QE
import java.util.List; BG8/
E]8uj8K3]
import org.flyware.util.page.Page; ZW9OPwV
K@JaN/OM
import net.sf.hibernate.HibernateException; ]v0Z[l>yf
_g
fmo
/** [Y$TVwFwX
* @author Joa TqL+^:cq
*/ ZDAW>H<
publicinterface UserDAO extends BaseDAO { ).IyjHY
vBJxhK-
publicList getUserByName(String name)throws dC8}Ttc}
*`|xa@1v`
HibernateException; 3u/AqL
!yVY[
publicint getUserCount()throws HibernateException; dA (n,@{
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publicList getUserByPage(Page page)throws tHo|8c~[
rQ_]%ies8
HibernateException; t,dm3+R
Ssuz%*
} /M::x+/T
w[\rS`J
#Q)r6V:
|:&O!36
y.I&x#(^
java代码: f1v4h[)-
UPP"-`t
#qmsZHd}b
/*Created on 2005-7-15*/ f>$RR_
package com.adt.dao.impl; fN&uat