Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 6ZQ$5PY
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 ^vZu[m
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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 aN';_tGvK
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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 <!-#]6
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分页支持类: a
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java代码:
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package com.javaeye.common.util; '<h@h*R
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import java.util.List; ]_hXg*?
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publicclass PaginationSupport { nIl<2H]F`
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publicfinalstaticint PAGESIZE = 30; zc1~ q
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privateint pageSize = PAGESIZE; 85](,YYz
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privateList items; h[]3#
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privateint totalCount; ^3nB2G.ax
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privateint[] indexes = newint[0]; OKCX>'j:S
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privateint startIndex = 0; (N{
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public PaginationSupport(List items, int )J&!>GP
{#l@9r%
totalCount){ ?Q6ZZQ~
setPageSize(PAGESIZE); }9?fb[]
setTotalCount(totalCount); .-:6L2
setItems(items); {ZgycMS
setStartIndex(0); 4OdK@+-8U
} QezDm^<
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public PaginationSupport(List items, int
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totalCount, int startIndex){ ^j'vM\^`ml
setPageSize(PAGESIZE); ntF#x.1Pm
setTotalCount(totalCount); 0.!Q4bhD
setItems(items); 5O"wPsl
setStartIndex(startIndex); uzL IllVX*
} W97
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public PaginationSupport(List items, int =_d-MJy~6
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totalCount, int pageSize, int startIndex){ :w4I+*]
setPageSize(pageSize); z|G 39
setTotalCount(totalCount); $]iRfXv,l!
setItems(items); XXZ$^W&
setStartIndex(startIndex); ~{s7(^ P
} Pl[WCh
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publicList getItems(){ 7033#@_
return items; s}":lXkrw
} mQt?d?6
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publicvoid setItems(List items){ .g6(07TyV
this.items = items; Ps{}SZn
} N+NS\Y5
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publicint getPageSize(){ Dz&<6#L<
return pageSize; ctL,Mqr\Z
} ;AgXl%Q
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publicvoid setPageSize(int pageSize){ \6v*c;ZF
this.pageSize = pageSize; E- rXYNfy
} (`Q_^Bfyl
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publicint getTotalCount(){ (
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return totalCount; 3mM.#2=@>
} >a1ovKF
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publicvoid setTotalCount(int totalCount){ h3:dO|Z
if(totalCount > 0){ |CjE}5Op>
this.totalCount = totalCount; W,)qE^+
int count = totalCount / dKTUW<C
p uLQ_MNV
pageSize; ;/-#oW@gQ
if(totalCount % pageSize > 0) `F1 ( v
count++; ;u: }rA)
indexes = newint[count]; iG;GAw|E
for(int i = 0; i < count; i++){ Xa32p_|5~
indexes = pageSize * @Y2&v956
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i; IK^jzx
} 18U
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}else{ O}_Z"y
this.totalCount = 0; FzGla} )
} nLjo3yvV..
} h|Uy!?l
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publicint[] getIndexes(){ u.sn"G-c
return indexes; ZX!u\O|w
} />9?/&N6"
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publicvoid setIndexes(int[] indexes){ v><uHjP
this.indexes = indexes; U0W- X9>y
} nANoy6z:
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publicint getStartIndex(){ h47l;`kD-#
return startIndex; #0j,1NpL
} ROHr%'owgL
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publicvoid setStartIndex(int startIndex){ nY<hfqof
if(totalCount <= 0) vMOit,{
this.startIndex = 0; 1JoRP~mMxa
elseif(startIndex >= totalCount) #5x[Z[m
this.startIndex = indexes Kr]`.@/.S
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[indexes.length - 1]; 5:H9B
elseif(startIndex < 0) *xOrt)D=
this.startIndex = 0; GlVD!0
else{ T9+ ?A
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this.startIndex = indexes +}@HtjM
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[startIndex / pageSize]; cHMS[.=;
} Y+tXWN"8
} Y@Kp'+t(!
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publicint getNextIndex(){ z_p/.kQ'5
int nextIndex = getStartIndex() + *tda_B
2
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pageSize; fH7o,U|
if(nextIndex >= totalCount) uFT&r|
return getStartIndex(); AhARBgf<
else qe:,%a-9
return nextIndex; t>T |\WAAL
} f9g#pyH4
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publicint getPreviousIndex(){ ?q<"!U|e
int previousIndex = getStartIndex() - A8R}W=
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pageSize; ODH@/
if(previousIndex < 0) n(b(H`1n
return0; (SLAq$gvd
else ~o+HAc`=v
return previousIndex; e/m,PE
} h+x"?^
x.+}-(`W#~
} '%`Wy@
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抽象业务类 u9FXZK7
java代码: qF(F<$B
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/** OgfmyYMtc
* Created on 2005-7-12 vb}; _/#?
*/ sSi1;9^o
package com.javaeye.common.business; MX?K3=j @>
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import java.io.Serializable; xaWm wsym
import java.util.List;
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import org.hibernate.Criteria; ;jTP|q?|{
import org.hibernate.HibernateException; hp}J_/+4n
import org.hibernate.Session; @U%I 6 t
import org.hibernate.criterion.DetachedCriteria; /)xG%J7H
import org.hibernate.criterion.Projections; OCF\*Sx
import |Q^ZI
9
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org.springframework.orm.hibernate3.HibernateCallback; @#}9?>UV
import vS:%(Y"!<
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org.springframework.orm.hibernate3.support.HibernateDaoS 02} &h
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upport; ]S[zD|U%
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import com.javaeye.common.util.PaginationSupport; IEdC
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public abstract class AbstractManager extends dx@#6Fhy
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HibernateDaoSupport { W 0Q-&4
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privateboolean cacheQueries = false; <w}k9(Ds
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privateString queryCacheRegion; 5f7;pS<
})Rmu."\
publicvoid setCacheQueries(boolean Roy0?6O
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cacheQueries){ qu8i Jq
this.cacheQueries = cacheQueries; bv>;%TF
} Ix%h/=I
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publicvoid setQueryCacheRegion(String LQ?J
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queryCacheRegion){ _$By c(.c
this.queryCacheRegion = Wy,DA^\ef
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queryCacheRegion; zGu(y@o
} gqJ&Q
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publicvoid save(finalObject entity){ *L/_ v
getHibernateTemplate().save(entity); YcGSZ0vQ
} ,qpn4`zE~
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publicvoid persist(finalObject entity){ BG"~yyKA
getHibernateTemplate().save(entity); Tn/T:7C
} iqghcY)
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publicvoid update(finalObject entity){ dx[<@f2c
getHibernateTemplate().update(entity); qJFBdJU (1
} "tUXYY
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publicvoid delete(finalObject entity){ ~o%|#-S
getHibernateTemplate().delete(entity); 6!/e_a
} h/`OG>./
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publicObject load(finalClass entity, g||{Qmr=1
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finalSerializable id){ EKk~~PhW 8
return getHibernateTemplate().load {.z2n>1J{T
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(entity, id); |t|+pBB
} z['>`Kt
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publicObject get(finalClass entity, ];^A8?
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finalSerializable id){ `Ten2(D
return getHibernateTemplate().get Wk'KN o
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(entity, id); N6$pOQ
} =XJ
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publicList findAll(finalClass entity){ J:'cj5@
return getHibernateTemplate().find("from WO)rJr!C
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" + entity.getName()); tk<dp7y7
} ]OM|Oo
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publicList findByNamedQuery(finalString G|Ic6Sd
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namedQuery){ vML01SAi
return getHibernateTemplate Gk8"fs
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().findByNamedQuery(namedQuery); FsY}mql
} 6/T
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publicList findByNamedQuery(finalString query, 7h<Q{X<A
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finalObject parameter){ B=7bQli}
return getHibernateTemplate q+3Z3v
,!|/|4vh
().findByNamedQuery(query, parameter); OTL=(k
} {IYfq)c
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publicList findByNamedQuery(finalString query, &iR>:=ksN
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finalObject[] parameters){ 4!d&Zc>C4
return getHibernateTemplate 782be-n
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().findByNamedQuery(query, parameters); K!5QFO4
} 234OJ?
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publicList find(finalString query){ IaH8#3+a
return getHibernateTemplate().find 8uM >Up X
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(query); KFdV_e5lU
} nyi}~sB
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publicList find(finalString query, finalObject 5.]+K<:h"A
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parameter){ LgjL+w19
return getHibernateTemplate().find "'4R_R
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(query, parameter); L|qQZ=
} =;7gxV3;
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public PaginationSupport findPageByCriteria (LA%q6
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(final DetachedCriteria detachedCriteria){ G`8gI)$u
return findPageByCriteria iP~5=
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); 6,G1:BV{K
} wxkCmrV
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public PaginationSupport findPageByCriteria 3DV';
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(final DetachedCriteria detachedCriteria, finalint <MB]W`5
9s6@AJf
startIndex){ II3)Cz}xRG
return findPageByCriteria $/Gvz)M
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(detachedCriteria, PaginationSupport.PAGESIZE, >E|@3g
+2
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startIndex); `$ZX]6G
} Y|_#yb
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public PaginationSupport findPageByCriteria -GD_xk
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(final DetachedCriteria detachedCriteria, finalint NEa:
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pageSize, wOOBW0tj
finalint startIndex){ dQYb)4ir
return(PaginationSupport) ^ ~:f02[D
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getHibernateTemplate().execute(new HibernateCallback(){ U[*VNJSp
publicObject doInHibernate 5DK>4H:
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(Session session)throws HibernateException { gV$j ]
Criteria criteria = -$f~V\M
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detachedCriteria.getExecutableCriteria(session); rIH/<@+
int totalCount = 'C8VD+p
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((Integer) criteria.setProjection(Projections.rowCount n .ZLR=P4
8i!AJF9IQ}
()).uniqueResult()).intValue(); nBI?~hkP3
criteria.setProjection u =z$**M^
:6S!1roi
(null); VLC<ju!
List items = Y ( x_bJ
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criteria.setFirstResult(startIndex).setMaxResults %'a%ynFs
<+o-{{E[
(pageSize).list(); jl;_lcO
PaginationSupport ps = rL3<r
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new PaginationSupport(items, totalCount, pageSize, ;,[6 n|M
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startIndex); DZ92;m
return ps; &)JQ6J_|\
} =.(yOUI
}, true); >A5R
} %@#+Xpa+
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public List findAllByCriteria(final U`N|pPe:w
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DetachedCriteria detachedCriteria){ V>ML-s9
return(List) getHibernateTemplate L^bt-QbhO
J(JsfU4
().execute(new HibernateCallback(){ G3'>KMa.
publicObject doInHibernate rl4B(NZi}
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(Session session)throws HibernateException { v#0F1a?]D
Criteria criteria = 8^\}\@
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detachedCriteria.getExecutableCriteria(session); 4e~^G
return criteria.list(); u.sF/T=6f
} R*a5bKr
}, true); xI}o8G KQq
} k"D6Vyy`
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public int getCountByCriteria(final I=o[\?u*_
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DetachedCriteria detachedCriteria){ ("Z;)s4q
Integer count = (Integer) s0uI;WMg
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getHibernateTemplate().execute(new HibernateCallback(){ >$SP2(Y~
publicObject doInHibernate &[:MTK?x!
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(Session session)throws HibernateException { sd9$4k"
Criteria criteria = i!+D
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detachedCriteria.getExecutableCriteria(session); vQ/}E@?u
return ph{p[QI:{X
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criteria.setProjection(Projections.rowCount 1+6:K._C(m
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()).uniqueResult(); s7.2EkGl=
} .Uq?SmK
}, true); b~X^vXIv%%
return count.intValue(); e8g"QDc
} Lh3>xZy"-z
} `Fa49B|`D
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用户在web层构造查询条件detachedCriteria,和可选的 Py7!_TX
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 i)9}+M5
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PaginationSupport的实例ps。 arJ4^ d
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ps.getItems()得到已分页好的结果集 IN=pki|.
ps.getIndexes()得到分页索引的数组 VH[r@Pn
ps.getTotalCount()得到总结果数 BCsz8U!
ps.getStartIndex()当前分页索引 wI.i\S
ps.getNextIndex()下一页索引 Vcn04j#Q
ps.getPreviousIndex()上一页索引 Vij P;
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 j,%@%upM
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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
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一下代码重构了。 (t&]u7Atr
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我把原本我的做法也提供出来供大家讨论吧: 4w,=6|#
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首先,为了实现分页查询,我封装了一个Page类: @(>XSTh9
java代码: W}m-5L
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/*Created on 2005-4-14*/ q-s! hiK
package org.flyware.util.page; X-1<YG
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/** O@JgVdgf
* @author Joa
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* &y`
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*/ ' >(])Oq,
publicclass Page { HQHFD0hv
1d/-SxhZ
/** imply if the page has previous page */
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privateboolean hasPrePage; i0F.c\
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/** imply if the page has next page */ <$\vL
privateboolean hasNextPage; kN3 T/96
tP; &$y.8
/** the number of every page */ )|;*[S4
privateint everyPage; is=sV:j:
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/** the total page number */ /H#- \r&r
privateint totalPage; []HMUL]"
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/** the number of current page */ y,qP$5xiq
privateint currentPage; fR_
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/** the begin index of the records by the current H I/]s^aL
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query */ 0kN;SSX!
privateint beginIndex; '[#a-8-JY_
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/** The default constructor */ Pn@k)g
public Page(){ %bI(
|8I #`
} 8r
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/** construct the page by everyPage (IXiwu
* @param everyPage ^l1tQnj)7
* */ =H*}{'#
public Page(int everyPage){ xe^*\6Y
this.everyPage = everyPage; x_9<&Aj6
} *8}Y0V\s
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/** The whole constructor */ (]wi^dE
public Page(boolean hasPrePage, boolean hasNextPage, }.Eq_wP<
WqN=D5
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int everyPage, int totalPage, 8@%Xd^
int currentPage, int beginIndex){ [% chN/
this.hasPrePage = hasPrePage; }Ictnb
this.hasNextPage = hasNextPage; "=4`RM
this.everyPage = everyPage; 9 tZ)#@\
this.totalPage = totalPage;
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this.currentPage = currentPage; %bf+Y7m
this.beginIndex = beginIndex; $ q*kD#;mh
} -1Y9-nn[m
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/** L(!4e
* @return #!p=P<4M
* Returns the beginIndex. 6cof Zc$
*/ s
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publicint getBeginIndex(){ {#q']YDe`
return beginIndex; y e!Bfz>
} EM/NT/
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/** ~ZU;0#
* @param beginIndex kTQ:k
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* The beginIndex to set. A7U'>r_.
*/ CG'NC\x5
publicvoid setBeginIndex(int beginIndex){ R`=3lY;
this.beginIndex = beginIndex; 3nuf3)
} Lm+!/e
)
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/** <B6@q4Q
* @return ${'gyD
* Returns the currentPage. D^Dm, -
*/ <'A>7M~h?*
publicint getCurrentPage(){ C%d 4ItB >
return currentPage; 7}bjJR "
} ];Whvdnv
lJ]r%YlF
/** !f_GR Pj'
* @param currentPage P# 2&?.d\
* The currentPage to set. /^96|
*/ mY-Z$8r
publicvoid setCurrentPage(int currentPage){ E%eao$
this.currentPage = currentPage; 3ojK2F(1D
} 1wUZ0r1'
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/** hZnT`!iFE^
* @return -Nmf}`_
* Returns the everyPage. KsYT3
*/ O{8"f\*
publicint getEveryPage(){ b3b 4'l
return everyPage; hTI8hh
} .;WJ(kB\U
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/** LLmgk"
* @param everyPage tW5\Ktjno
* The everyPage to set. a:@9GmtV&
*/ vy/U""w`
publicvoid setEveryPage(int everyPage){ kF'^!Hp
this.everyPage = everyPage; #1Mk9sxo
} EZ #UdK_
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/** @RotJl/>
* @return sb4)@/Q7j
* Returns the hasNextPage. ih`/1n
*/ (PGmA>BT
publicboolean getHasNextPage(){ (Br$(XJoK}
return hasNextPage; `.;7O27A^%
} cb&y8!ci~
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/** 5X&<+{bX
* @param hasNextPage Bir}X
* The hasNextPage to set. oSNB\G<
*/ 80$P35Q"
publicvoid setHasNextPage(boolean hasNextPage){ ]Oc
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this.hasNextPage = hasNextPage; yP0P-8
} iM2
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/** `'Ta=kd3
* @return ;t%L(J
* Returns the hasPrePage. L:YsAv
*/ 1hZM))
publicboolean getHasPrePage(){ y:4Sw#M%(
return hasPrePage; ;0E"4(S.q1
} j-gLX
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/** CkoPno
* @param hasPrePage a2/r$Tgm
* The hasPrePage to set. 9?D7"P+
*/ s
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publicvoid setHasPrePage(boolean hasPrePage){ X1<)B]y
this.hasPrePage = hasPrePage; Y'fI4
} 'G(N,vu[@
37p0*%a":
/** #BS]wj2#
* @return Returns the totalPage. z+" :,#
* SUD]Wl7G`r
*/ =)M 8>>l
publicint getTotalPage(){ -Kg@Sj/U}R
return totalPage; 'lC"wP&$
} '5ky<
x|0Q\<mEe
/** Y@eHp-[
* @param totalPage H[@}ri<
* The totalPage to set. R'dF<&Kj|
*/ 3JW9G04.
publicvoid setTotalPage(int totalPage){ fH`1dU
this.totalPage = totalPage; md$[Bs9
} } Q1$v~
vzi=[A
} &8"a 7$
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p5F[( H|9
^%_B'X9
/<:9NP'^
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 ;x^&@G8W`
EoU}@MjM~
个PageUtil,负责对Page对象进行构造: L*FmJ{Yf
java代码: gY0*u+LF
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6FEtq,;0w
/*Created on 2005-4-14*/ /oiAAB27
package org.flyware.util.page; JS(KCY 9
fS#/-wugOB
import org.apache.commons.logging.Log; &tMvs<q,
import org.apache.commons.logging.LogFactory; @1n0<V/
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/** 7/Lbs
* @author Joa czMLvPXRx
* bSz6O/A/
*/ LV8,nTYvE
publicclass PageUtil { AX'(xb,
}i[i{lKj
privatestaticfinal Log logger = LogFactory.getLog t ?bq~!X
/SMp`Q88
(PageUtil.class); S\0"G*
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/** #S<>+,Lk
* Use the origin page to create a new page }GkEv}~t
* @param page nWXI*%m5
* @param totalRecords :Hd?0eZ|
* @return CWBsiL
f
*/ Q]6nW[@j'
publicstatic Page createPage(Page page, int =Rb, `%
$Fr2oSTT)
totalRecords){ M8juab%y
return createPage(page.getEveryPage(), rcI(6P<*
;uoH+`pf
page.getCurrentPage(), totalRecords); K?I@'B'
} 1Za\T?V
I">z#@CT
/** a*SJHBB
* the basic page utils not including exception #{h4lte
Y!POUMA
}A
handler {xM%3
* @param everyPage _^a.kF
* @param currentPage / _}v|E0
* @param totalRecords H>M%5bj
* @return page 8kMMQ ES
*/ kJDMIh|g
publicstatic Page createPage(int everyPage, int t Ac;O[L
Q 5@~0
currentPage, int totalRecords){ a'T|p)N.;T
everyPage = getEveryPage(everyPage); j,1,;
currentPage = getCurrentPage(currentPage); <EBp X
int beginIndex = getBeginIndex(everyPage, sXhtn'<v
8:t-I]dzk
currentPage); a[(n91J0
int totalPage = getTotalPage(everyPage, i( c2NPbX
Q;aZpi-E"
totalRecords); E#HO0]S
boolean hasNextPage = hasNextPage(currentPage, &)bar.vw/
6eS#L2 1*
totalPage); :=i0$k<E/
boolean hasPrePage = hasPrePage(currentPage); /au\OBUge
cOUO_xp(
returnnew Page(hasPrePage, hasNextPage, ~(%G;fZ?x
everyPage, totalPage, pM#:OlqC
currentPage, m7RWu I,
iz*aBXV A[
beginIndex); |Cen5s
W&
} H<NYm#a"
wV-cpJ,}
privatestaticint getEveryPage(int everyPage){ Z&.FJZUP
return everyPage == 0 ? 10 : everyPage; *E$D,
} zZf#E@=$|
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privatestaticint getCurrentPage(int currentPage){ ^ g4)aaBZ
return currentPage == 0 ? 1 : currentPage; U3za}3
} RsV<*s
t8P>s})[4
privatestaticint getBeginIndex(int everyPage, int 55!9U :{
VS}Vl
currentPage){ gH_r'j
return(currentPage - 1) * everyPage; +- .BF"}
} 1%-?e``.
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privatestaticint getTotalPage(int everyPage, int Ab(bvS8r$
QY^ y(I49
totalRecords){ EI_J7J+
int totalPage = 0; IsRsjhg8x
@ym7hk.
if(totalRecords % everyPage == 0) Yb?#vp I
totalPage = totalRecords / everyPage; Uc6U!X
else R/b=!<
totalPage = totalRecords / everyPage + 1 ; 2#E;5UYu
*=sU+x&X
return totalPage; 1i>)@{P&BN
} ;ib~c,
x`lBG%Y[-v
privatestaticboolean hasPrePage(int currentPage){ gq0gr?
return currentPage == 1 ? false : true;
V!Joh5=a
} +'KM~c?]
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privatestaticboolean hasNextPage(int currentPage, I+<`}
*}v'y{;
int totalPage){ T4f:0r;^f*
return currentPage == totalPage || totalPage == mWGT
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0 ? false : true; }>OE"#si
} Hv`Zc*
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} m#S ZI}
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my} P\r.
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Z7f~|}
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。 d@l;dos),
ILVbbC`D
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 X:e'@]Z)?
N&GcWcq
做法如下: 3{c&%F~!
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 *FAg^G&1
N&ddO-r[s
的信息,和一个结果集List: WI6er;D
java代码: xj~6,;83xR
?Z!KV=
u(o @_6
/*Created on 2005-6-13*/ 7dakj>JM
package com.adt.bo; ::5-UxGL<2
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import java.util.List; +X?jf.4
`C()H@;
import org.flyware.util.page.Page; gTq-\k(
+amvQ];?Q8
/** awawq9)Y
* @author Joa "ulaF+
*/ JBYQ7SsAS0
publicclass Result { dKMuo'H'%
@V-ZV
private Page page; 81n%2G
TcIUo!:z
private List content; P*LcWrK
'0=U+Egp
/** hlVP_h"z
* The default constructor K
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*/ 0hv[Ff
public Result(){ Z/I!\
super(); eGE%c1H9a
} hT_snb;ow
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/** IM#+@vv
* The constructor using fields p!691LI
* O3_Mrn(R
* @param page !of7]s
* @param content
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*/ X-duG*~
public Result(Page page, List content){ nJ? C 4\#3
this.page = page; >YW>=5_
this.content = content; -`;8~ wMN
} QZfPd\Q5
^w HMKC
/** .SsIU\[)
* @return Returns the content. f^]AyU;F:
*/ 55I>v3 w
publicList getContent(){ lt*k(JD
return content; g PfaiVY
} :Hd<S
m<yA]
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/** J8%|Gd0#4
* @return Returns the page. IQ_0[
*/ nFP2wvFM
public Page getPage(){ P]TT
return page; 01dx}L@hz
} 8fN0"pymo
d.+vjMI
/** XX F9oy8
* @param content JC#@sJ4az)
* The content to set. YOY+z\Q
*/ U%4g:s
public void setContent(List content){ -Z Z$
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this.content = content; 06`__$@h
} _(jE](,
UqHO S{\Sz
/** 08f~vw"
* @param page 1_t Dp&UO
* The page to set. d;=,/a
*/ 9j 8t<5s
publicvoid setPage(Page page){ OBl8kH(b>
this.page = page; ZMe| fn
} wx!*fy4hL
} V;6M[ic}
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i
<Hp"ZCN
fH.W
kAE1
"VeUOdNA>
2. 编写业务逻辑接口,并实现它(UserManager, d5%*^nMpY
1^;h:,e6
UserManagerImpl) rEf\|x=st:
java代码: "tark'
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W>~%6K>p
/*Created on 2005-7-15*/ 7L]?)2=
package com.adt.service; Gh
pd
k;
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}Q
import net.sf.hibernate.HibernateException; !$?@;}=
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i
import org.flyware.util.page.Page; (w-u"1&
@r43F$bcqo
import com.adt.bo.Result; ~Qsj)9
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/** 3oKGeB;Ja
* @author Joa [0LqZ<\5
*/ {q)B@#p
publicinterface UserManager { 8.^U6xA
e^GW[lT
public Result listUser(Page page)throws {|gJC>f@
z|<oxF.
HibernateException; ]Yu+M3Fq
_HK&KY
} 6'ZnyWb
M;Rw]M
]*@$%iCPE
!VHIl&Mos
t/ 1NTa
java代码: WK}+f4tdW[
=QfKDA
aX%Zuyny
/*Created on 2005-7-15*/ "k|`xn
package com.adt.service.impl; #[W[|m
UT~2}B9fc
import java.util.List; EAB+kY
K)+l 6Q
import net.sf.hibernate.HibernateException; ?GarD3#A
#<PdZl R
import org.flyware.util.page.Page; 5Nb_K`Vp*
import org.flyware.util.page.PageUtil; ehusI-q
5)7mjyo%
import com.adt.bo.Result; }#x3IE6'
import com.adt.dao.UserDAO; 55LF
import com.adt.exception.ObjectNotFoundException; 1hyah.i]Y
import com.adt.service.UserManager; Q/n.T0Z^
I
6YT|R
/** Bqi2n'^O2
* @author Joa
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*/ .^S78hr]n
publicclass UserManagerImpl implements UserManager { F\R}no5C
emB D@r
private UserDAO userDAO; -ikuj
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/** PL$F;d
* @param userDAO The userDAO to set. UMwMXmZNJ
*/ ~ p.W*skD
publicvoid setUserDAO(UserDAO userDAO){ P i!r}m
this.userDAO = userDAO; )hW {>Y3x
} }.) 43(>]
%QgAilj,
/* (non-Javadoc) 2P_^@g
* @see com.adt.service.UserManager#listUser $ F7gH
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(org.flyware.util.page.Page) "EYjY->
*/ >Ro n+
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public Result listUser(Page page)throws r)]CZ])
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HibernateException, ObjectNotFoundException { ,M&0<k\
int totalRecords = userDAO.getUserCount(); Ti|++oC/&
if(totalRecords == 0) h&M
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throw new ObjectNotFoundException w00\1'-Kz
SzlfA%4+GR
("userNotExist"); 64' ]F1p0
page = PageUtil.createPage(page, totalRecords); !TL}~D:J
List users = userDAO.getUserByPage(page); K('lH-3wS
returnnew Result(page, users); 51opP8
} d 4\E
>MWpYp
} ynbpew aa
P&3/nL$9N
:@`(}5F4
s|j<b#<xQ
&9_\E{o%]
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 <o7#?AcPu
yXV|4
询,接下来编写UserDAO的代码: u?3NBc$~A
3. UserDAO 和 UserDAOImpl: F2`htM@,
java代码: '#i]SU&*
AOx3QgC^NO
lhA
s!\F
/*Created on 2005-7-15*/ 9>&tMq
package com.adt.dao; QcG5PV
EhPVK6@
import java.util.List; .hlQ?\
Qy^z *s
import org.flyware.util.page.Page; )cKtc
nuO3UD3
import net.sf.hibernate.HibernateException; $jed{N7Y
QS [B
/** W+f&%En
* @author Joa @ZkAul0@
*/ B+e_Y\Bu
publicinterface UserDAO extends BaseDAO { tkN3BQ
NC.P2^%
publicList getUserByName(String name)throws QYTTP6 Gz+
7vpN6YP
HibernateException; q _]
Q P=[ Vw
publicint getUserCount()throws HibernateException; $JhZ'Z
k=mT!
publicList getUserByPage(Page page)throws n;kciTD%wK
('**nP
HibernateException; !P~ PF:W~|
*pTO|x{
} (}FW])y
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v*H &