Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 By(:%=.
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 98eiYh
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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 EM!# FJh
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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 ?rID fEvV
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分页支持类: /1
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java代码: u,e'5,`N
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package com.javaeye.common.util; Cv862kP
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import java.util.List; M-1 VB5
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publicclass PaginationSupport { .}>d[},F
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publicfinalstaticint PAGESIZE = 30; +6t<FH
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privateint pageSize = PAGESIZE; //cj$}Rn!
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privateList items; "@U9'rKx
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privateint totalCount; |3{DlZ2S
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privateint[] indexes = newint[0]; .4Ob?ZS(
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privateint startIndex = 0; v9R#=m/=
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public PaginationSupport(List items, int jV
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totalCount){ YY-{&+,
setPageSize(PAGESIZE); `l,=iy$
setTotalCount(totalCount); 6}^0/76^,
setItems(items); d2lOx|jt
setStartIndex(0); 4<._)_m
} oR (hL4Dc
v(D{_
public PaginationSupport(List items, int n B4)%
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totalCount, int startIndex){ dd1m~Gm
setPageSize(PAGESIZE); W$LaXytmak
setTotalCount(totalCount); U;Z6o1G
setItems(items); f"t\-ux.b
setStartIndex(startIndex); V&`\ s5Q
} RN\4y{@
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public PaginationSupport(List items, int 4]9+
?hUC#{
totalCount, int pageSize, int startIndex){ 4GWt.+{J$
setPageSize(pageSize); YVt#( jl
setTotalCount(totalCount); p'UY Ht
setItems(items); :q=u+h_
setStartIndex(startIndex); [^xLK
} xc dy/J&
#-
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publicList getItems(){ nN" Y~W^k
return items; q !\Ht2$b
} #g[jwl'
N),bhYS]
publicvoid setItems(List items){ (pM5B8U
this.items = items; S|!)_RL
} a@ `1 5O:
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publicint getPageSize(){ K=Z~$)Og)
return pageSize; ULc oti=,
} 3a PCi>i!_
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publicvoid setPageSize(int pageSize){ x*td
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this.pageSize = pageSize; z`UL)W
} e3w4@V`
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publicint getTotalCount(){ @
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return totalCount; 2[f8"'lUQ
} [tYly`F
taOD,}c|$
publicvoid setTotalCount(int totalCount){ yO Ed8
if(totalCount > 0){ MGpP'G:v
this.totalCount = totalCount; D /ysS$!{
int count = totalCount / O{Bll;C
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pageSize; Yqz(@( %
if(totalCount % pageSize > 0) {<0=y#@u
count++; i5wXT
indexes = newint[count]; +U/+iI>0
for(int i = 0; i < count; i++){ .),ql_sXr
indexes = pageSize * 19-|.9m(
sv`+?hjG
i; S@i*+&Ot
} SA_5..
}else{ =au7'i |6
this.totalCount = 0; kBolDPvBG
} v0euvs
} x'Pp!
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publicint[] getIndexes(){ -JOtvJIQI
return indexes; I;iJa@HWQ
} SrGX4
*olV Y/'O
publicvoid setIndexes(int[] indexes){ gyi<ot;
this.indexes = indexes; 1{@f:~ v?
} y ,][
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publicint getStartIndex(){ XnC`JO+7M
return startIndex; 2eErvfC[
} 0'u2xe
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publicvoid setStartIndex(int startIndex){ j8WMGSrrF
if(totalCount <= 0) ! bbVa/
this.startIndex = 0; xo{3r\u?}
elseif(startIndex >= totalCount) ZuZe8&
this.startIndex = indexes yZ?|u57
I4'mU$)U
[indexes.length - 1]; MX!t/&X(n
elseif(startIndex < 0) gP=(2EVE
this.startIndex = 0; df@I C@`pB
else{
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this.startIndex = indexes ( iM*Y"Y
1haH2F^q3
[startIndex / pageSize]; #B7_5y^
} lx9tUTaus/
} _ dFZR
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publicint getNextIndex(){ 7"}<J7"})
int nextIndex = getStartIndex() + +~~FfIzf#
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pageSize; j8/rd
if(nextIndex >= totalCount) I*cB
Ha
return getStartIndex(); s5{N+O)~S
else Fw,'a
return nextIndex; 2<&lrsh
} c%p7?3Ry
b+/XVEsr
publicint getPreviousIndex(){ -I."= c%
int previousIndex = getStartIndex() - N"-</kzV
i}SJ
pageSize; DY2r6bcn`
if(previousIndex < 0) E?%SOU<
return0; .xJW=G{/
else 951"0S`Lo
return previousIndex; PDN3=PAR/A
} c_$9z>$
. ]
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抽象业务类 V%k #M
java代码: {#>>dILPr
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/** j2GO ZKy
* Created on 2005-7-12 J:6wFmU
*/ ]fc9m~0N,\
package com.javaeye.common.business; #1-y[w/
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import java.io.Serializable; [UO?L2$&
import java.util.List; aH@Ux?-}
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import org.hibernate.Criteria; ;3ZHm*xJx
import org.hibernate.HibernateException; ?-"xP'#
import org.hibernate.Session; "4W@p'
import org.hibernate.criterion.DetachedCriteria; ?UD2}D[M
import org.hibernate.criterion.Projections; k-5Enbkr
import w74)kIi
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org.springframework.orm.hibernate3.HibernateCallback; CXC,@T
import QcZ*dI7]:
7.hgne'<
org.springframework.orm.hibernate3.support.HibernateDaoS /?<tjK' "H
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upport; Gb)!]:8
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import com.javaeye.common.util.PaginationSupport; M4hzf
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public abstract class AbstractManager extends 8m? 9?OV5
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HibernateDaoSupport { lMpjE
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privateboolean cacheQueries = false; B8Ob~?
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privateString queryCacheRegion; fiDwa
;,
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publicvoid setCacheQueries(boolean C$MaJHkiF
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cacheQueries){ }9n{E-bj *
this.cacheQueries = cacheQueries; ex_Zw+n
} F8e]sa$K\
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publicvoid setQueryCacheRegion(String nC Mv&{~
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queryCacheRegion){ q}-q[p?
5
this.queryCacheRegion = -{z.8p}IW
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queryCacheRegion; 6"+/Imb-
} nAc02lJh|
S}=d74(/n
publicvoid save(finalObject entity){ 3+6s}u)
getHibernateTemplate().save(entity); pk&kJ307
} dP8b\H
$umh&z/
publicvoid persist(finalObject entity){ ~*-(_<FH
getHibernateTemplate().save(entity); c^^[~YWj
} -Y]ue*k{
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publicvoid update(finalObject entity){ >;@ _TAF
getHibernateTemplate().update(entity); sGx"ja+
} xyGk\= S
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publicvoid delete(finalObject entity){ <DG=qP6O
getHibernateTemplate().delete(entity); p4m9@\gn
} anwMG0
CA2 ,
publicObject load(finalClass entity, /P<K)a4GM
qTM,'7Rwn
finalSerializable id){ KPGo*mY
return getHibernateTemplate().load #R_IF&7
<5qXC.{Cyp
(entity, id); fmH"&>Loc
} CXqU<a&
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publicObject get(finalClass entity, X"V,3gDG
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finalSerializable id){ u&)+~X
return getHibernateTemplate().get (n'Mf
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(entity, id); FJ}RT*7_C
} sQt]Y&_/@
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publicList findAll(finalClass entity){ )4oTA@wR
return getHibernateTemplate().find("from %T:~N<8)
$~M#msK9
" + entity.getName()); "S6'<~s
} o!TG8aeb
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publicList findByNamedQuery(finalString s&vREx(
?C#=Q6
namedQuery){ Q v/}WnBk
return getHibernateTemplate 8 VMe#41
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().findByNamedQuery(namedQuery); Xy{\>}i]N
} ><odBM-
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publicList findByNamedQuery(finalString query, 5&5
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finalObject parameter){ eNN)2-96
return getHibernateTemplate ?+S jt
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().findByNamedQuery(query, parameter); Y{P0?`
} TxZ ^zj
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publicList findByNamedQuery(finalString query, 0eQwi l@
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finalObject[] parameters){ a4gJ-FE
return getHibernateTemplate %%[ "&
KCR6@{@
().findByNamedQuery(query, parameters); Obd@#uab
} Ps3wg=ni[
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publicList find(finalString query){ 7TCY$RcF,I
return getHibernateTemplate().find T_}9b
t!MGSB~
(query); 7hPiPv
} ]qZs^kQ
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publicList find(finalString query, finalObject E0XfM B]+
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parameter){ 7MXi_V;p<
return getHibernateTemplate().find eR,ePyA;
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(query, parameter); octBt`\Of
} Ew>E]Ys
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public PaginationSupport findPageByCriteria ^O_E
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(final DetachedCriteria detachedCriteria){ feOX]g#
return findPageByCriteria &6-udZB-
@ i$jyc
(detachedCriteria, PaginationSupport.PAGESIZE, 0); ;eYm+e^?.
} KiN8N=z
^8p=g-U\
public PaginationSupport findPageByCriteria ay}}v7)GM
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(final DetachedCriteria detachedCriteria, finalint x9UF
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startIndex){ sem:"
return findPageByCriteria @BbqYX
8PQKB*<dB"
(detachedCriteria, PaginationSupport.PAGESIZE, tz#Fy?pe
6?an._ C
startIndex); %3B0s?,I
} kWVaHZr
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public PaginationSupport findPageByCriteria |tl4I2AV
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(final DetachedCriteria detachedCriteria, finalint *3;H6
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pageSize, ~(W q 5<v
finalint startIndex){ /"w%?Ea
return(PaginationSupport) 7`113`1
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getHibernateTemplate().execute(new HibernateCallback(){ oWg"f*
publicObject doInHibernate V/C":!;
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(Session session)throws HibernateException { '!8'Xo@Go3
Criteria criteria = L1'R6W~%dN
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detachedCriteria.getExecutableCriteria(session); ~I'1\1
int totalCount = {OA2';3
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((Integer) criteria.setProjection(Projections.rowCount JDi\?m d.
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()).uniqueResult()).intValue(); u-yVc*<,
criteria.setProjection R(jp
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=
(null); hfUN~89;
List items = 5Oh>r K(
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criteria.setFirstResult(startIndex).setMaxResults <Lz/J-w
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(pageSize).list(); [T|_J$
;
PaginationSupport ps = hzG+s#
>NL4&MV:
new PaginationSupport(items, totalCount, pageSize, $9LI v
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startIndex); BhJag L ^o
return ps; zQpF,N<b
} 3zdm-5R.b
}, true); :Kc9k(3&r
} 8RGU^&
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public List findAllByCriteria(final jIpc^iu`,
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DetachedCriteria detachedCriteria){ kkvG=
return(List) getHibernateTemplate [FhFeW>
a!iG;:K
().execute(new HibernateCallback(){ ){~]-VK
publicObject doInHibernate %d3KE|&u
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(Session session)throws HibernateException { <d&9`e1Hc
Criteria criteria = 1?6zsA%N
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detachedCriteria.getExecutableCriteria(session); bq+Q$#F2X
return criteria.list(); {3s=U"\
} (RhGBgp
}, true); =a!w)z_rw
} VV'K$v3'N8
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public int getCountByCriteria(final tv,Z>&OM
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DetachedCriteria detachedCriteria){ tQTVP 2:Y
Integer count = (Integer) nIWZo ~
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getHibernateTemplate().execute(new HibernateCallback(){ [^rMM1^,OB
publicObject doInHibernate (P=q&]l[
j>D[iHrH
(Session session)throws HibernateException { wtm=
Criteria criteria = j,:vK
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detachedCriteria.getExecutableCriteria(session); J 'qhY'te
return o3=2`BvJ
}iOFB&)w
criteria.setProjection(Projections.rowCount ;:)1:Dy5
Y/|wOm;|
()).uniqueResult(); f9ziSD#
} (fSpY\JPI
}, true); -UTTJnu^
return count.intValue(); h_xHQf
} C71\9K*X
} yu^n;gWH
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用户在web层构造查询条件detachedCriteria,和可选的 zG"*B_l}+
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 5Xe1a'n5]
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PaginationSupport的实例ps。 CVk.Ez6
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ps.getItems()得到已分页好的结果集 CVa?L"lK
ps.getIndexes()得到分页索引的数组 U&PwEh4uG
ps.getTotalCount()得到总结果数 ggQB Q/ L
ps.getStartIndex()当前分页索引 $N@EH;{_0
ps.getNextIndex()下一页索引 # Vq"Cf
ps.getPreviousIndex()上一页索引 o?T01t=
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 -JMlk:~
j$%uip{
,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 nKR=/5a4Y
6/4?x)l3-
一下代码重构了。 =W*Js %4
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我把原本我的做法也提供出来供大家讨论吧: w%Bo7 'o)V
8dBG ZwyET
首先,为了实现分页查询,我封装了一个Page类: +f+#W
java代码: <"}Gvi
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/*Created on 2005-4-14*/ 9hNHcl.
package org.flyware.util.page; D
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/** SniKCqmC]
* @author Joa 0QakFt
* =xf7lN'
*/ i!tF{'*%#
publicclass Page { $h)VKW^\
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/** imply if the page has previous page */ K]bw1KK
privateboolean hasPrePage; M8,_E\*
Q*GJREC
/** imply if the page has next page */ >^U$2P
privateboolean hasNextPage; DqQ+8 w
<}vult^
/** the number of every page */ #("/ 1N6
privateint everyPage; @An "ClDa
"c'K8,+?
/** the total page number */ %XUV[L}
privateint totalPage; ^o|Gx
vz^w%67&
/** the number of current page */
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privateint currentPage; Gv$}>YJ
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/** the begin index of the records by the current P p]Ygt'u
;DG&HO
query */ 4/Wqeq,E8
privateint beginIndex; W/?\ 8AE
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/** The default constructor */ bVbh| AA
public Page(){ hj<h]dhp
0>aAI3E
} lY,dyNFHV
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/** construct the page by everyPage xGU~FU
* @param everyPage iuxS=3lT"K
* */ r^jiK\*
public Page(int everyPage){ A=+
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this.everyPage = everyPage; ryKc7<
} a-9Y U
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/** The whole constructor */ *fIb|r
public Page(boolean hasPrePage, boolean hasNextPage, *It`<F|
R{X@@t9@
u*:;O\6l
int everyPage, int totalPage, XoO#{7a
int currentPage, int beginIndex){ "T?hIX/p_
this.hasPrePage = hasPrePage; c-ud $0)c
this.hasNextPage = hasNextPage; *w/})Y3^
this.everyPage = everyPage; /^XGIQ/W
this.totalPage = totalPage; W :qQ
this.currentPage = currentPage; 1(;_1@P
this.beginIndex = beginIndex; \A ?B{*
} `1Cg)\&[e0
yM}Wg~:D:
/** u6pfc'GG g
* @return U,_jb}$Sq7
* Returns the beginIndex. .0gF&>I}
*/ 555*IT3b
publicint getBeginIndex(){ F79!B
return beginIndex; 7/:C[J4GTN
} E/Ng
B>!OW2q0D
/** pod=|(c
* @param beginIndex GCEcg&s=\S
* The beginIndex to set. o2J-&
*/ a7_ &;
publicvoid setBeginIndex(int beginIndex){ ZtFOIb*
this.beginIndex = beginIndex; 6')pM&`t
} XLeQxp=
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/** ZWVN(U
* @return kg@Okz N%
* Returns the currentPage. /@!%/Kl
*/ '%}k"&t$i
publicint getCurrentPage(){ nJ]oApb/-
return currentPage; (
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} FU~xKNr
oOj7y>Nm
/** [;E~A
* @param currentPage 82z\^a
* The currentPage to set. , '_y@9?I
*/ Xc!0'P0T
publicvoid setCurrentPage(int currentPage){ Z fQzA}QD
this.currentPage = currentPage; uq~Z
} Vp5i i]B4
tt=JvI9>
/** j-% vLL/
* @return n&j@7R
* Returns the everyPage. O8 \dMb
*/ &YU;
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publicint getEveryPage(){ ?mRGFS
return everyPage; Z/p>>SCak
} l[G&=/R@H
h:J0d~u
/** hyPVt6Gkj
* @param everyPage v *pN~}5
* The everyPage to set. &ml7368@
*/ +Ui @3Q
publicvoid setEveryPage(int everyPage){ fC \Cx;q-
this.everyPage = everyPage; LMF@-j%
} )rqb<O
bu
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/** 9MI~yIt`L
* @return 4=T.rVS[
* Returns the hasNextPage. ^>3q@,C]c
*/ sFvu@Wm'7W
publicboolean getHasNextPage(){ I&jiH)
return hasNextPage; q3CcXYY
} ecZT|X4u
HoTg7/iK
/** ?
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* @param hasNextPage YoT<]'
* The hasNextPage to set. d[p-zn.
*/ rKtr&w7X
publicvoid setHasNextPage(boolean hasNextPage){ dE`a1H%
this.hasNextPage = hasNextPage; )C@O7m*.4
} 8~~*/oCoJt
9Ez>srH(
/** e)#O-y
* @return /p&V72
* Returns the hasPrePage. Q^|ZoJS
*/ I 19 /
publicboolean getHasPrePage(){ WPN4mEow
return hasPrePage; D<DSK~
} ^~iFG+g5
3[RP:W@%
/** 8c6dTT4
* @param hasPrePage re$xeq\1P?
* The hasPrePage to set. $CXMeY{tOo
*/ `[&) X
publicvoid setHasPrePage(boolean hasPrePage){ EINjI:/D
this.hasPrePage = hasPrePage; GmONhh(k
} #D qVh!t"
+J`HI1
/** 0|D^_1W`R
* @return Returns the totalPage. tJ_6dH8Y
* <hS %I
*/ +bGj(T%+'
publicint getTotalPage(){ *i=+["A
return totalPage; FK^JCs^
} <fZ?F=
Ci}v +
/** +i@r-OL
* @param totalPage 2$fFl,v!z
* The totalPage to set. &J
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*/
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publicvoid setTotalPage(int totalPage){ ]z%X%wL
this.totalPage = totalPage; 5Dhpcgq<<
} XVlZ:kz
}:b6WN;c
} )}G?^rDH(
v4pFts$J
<#[_S$54
6c?;-5.
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上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 5*q!:$
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个PageUtil,负责对Page对象进行构造: ,D6hJ_:
java代码: Ez= Q{g
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/*Created on 2005-4-14*/ ':mw(`
package org.flyware.util.page; T~238C{vh
o9j*Yz
import org.apache.commons.logging.Log; [\Ks+S
import org.apache.commons.logging.LogFactory; &yQilyU{V
pZYcCc>6&
/** &sbKN[x M
* @author Joa (eG9b pqr
* t7t?xk!2
*/ ~)ZMGx
publicclass PageUtil { 7M|!N_ $
FR7DuH/f)
privatestaticfinal Log logger = LogFactory.getLog DR d|m<Z
t,YnweH
(PageUtil.class); cJ}J4?
-=tf)
/** )r9lT*z
* Use the origin page to create a new page \hm;p
* @param page \A{ [2
* @param totalRecords xD:t$~
* @return M_:_(y>l
*/ 3y[uH'
publicstatic Page createPage(Page page, int x344}\
zKY 9'y
totalRecords){ h.QsI`@f
return createPage(page.getEveryPage(), 3N5un`K7
y4V~fg;
page.getCurrentPage(), totalRecords); ke+3J\;>
} q{fgsc8v\
3? R56$-+
/** oCCTRLb02
* the basic page utils not including exception #|ppW fZQ
<l:c O$ m
handler (O&R-5m
* @param everyPage j,]KidDWm
* @param currentPage 1\[En/6
* @param totalRecords K4r"Q*h
* @return page JGJy_.C
*/ h()Ok9]
publicstatic Page createPage(int everyPage, int oPqWL9]
)\k({S
currentPage, int totalRecords){ ;fdROI
everyPage = getEveryPage(everyPage); G$eA(GE
currentPage = getCurrentPage(currentPage); 6>fQe8Y
int beginIndex = getBeginIndex(everyPage, IbC8DDTD
,y>%m;jL
currentPage); ;Sc}e/WJj
int totalPage = getTotalPage(everyPage,
@hb K
DX*eN"z[
totalRecords); rz@FUU:&
boolean hasNextPage = hasNextPage(currentPage, $jc&Tk#
rt_k }
totalPage); A ;06Zrf1
boolean hasPrePage = hasPrePage(currentPage); 2 SJN;A~}
^57G]$Q
returnnew Page(hasPrePage, hasNextPage, V5.=08L
everyPage, totalPage, 2;v1YKY
currentPage, cC NyW2'
k3 YDnMRA9
beginIndex); bh[`uRC}
} bzl-|+!yB
z;VAi=m
q
privatestaticint getEveryPage(int everyPage){ <{z*6FM!'
return everyPage == 0 ? 10 : everyPage; AjW5H*
} B@8M2Pl
-MCDX^>P
privatestaticint getCurrentPage(int currentPage){ dr54D
return currentPage == 0 ? 1 : currentPage; K[.*8
} o>#ue<Bc6
"B$r{ vG
privatestaticint getBeginIndex(int everyPage, int =vpXYj
,4OH9-Q1
currentPage){ ]"*sp
return(currentPage - 1) * everyPage; (>LJv |wn
} oZ/z{`
++m^z` D
privatestaticint getTotalPage(int everyPage, int lCX*Q{s22
)zKZ<;#y
totalRecords){ 4P>4d +
int totalPage = 0; )Rlh[Y& r
1 m>x5Dbk!
if(totalRecords % everyPage == 0) 68!W~%?pR
totalPage = totalRecords / everyPage; &4dh $w]q
else 'Avp16zg
totalPage = totalRecords / everyPage + 1 ; 1luRTI8^
}Qqi013E L
return totalPage; &>YdX$8x
} ;PA^.RB
.!B>pp(9
privatestaticboolean hasPrePage(int currentPage){ (FY<%.Pa
return currentPage == 1 ? false : true; M%vZcP
} ac2G;}B|
Rg3cqe#O/
privatestaticboolean hasNextPage(int currentPage, mF6 U{=
5, j&-{0W
int totalPage){ BJL*Dihm[
return currentPage == totalPage || totalPage == 2qN|<S&
(L2:|1P)
0 ? false : true; -J`VXG:M
} IHrG!owf
i'\7P-a
]bui"-tlK
} fbjT"jSzw
av!'UZP
]9 ArT$
gQ0W>\xz
ZDhl$m[m
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。 9iwSE(},
z5UY0>+VdS
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 g?mfpw Zj
6]mFw{6qn1
做法如下: `yvH0B -
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 x,+2k6Wn!
)M:pg%
的信息,和一个结果集List: zDD1EycH
java代码: F.DRGi.i
}[2|86,G;
/&eF,4
/*Created on 2005-6-13*/ :mI[fQ
package com.adt.bo; vz*'1ugaA
^(:Z*+X~>
import java.util.List; m0a <~
Z2t
r?]
import org.flyware.util.page.Page; ]i@WZ(
kzb%=EI
/** ^=1:!'*3D
* @author Joa ITmW/Im5
*/ W3HTQGV
publicclass Result { U~}cib5W5
#A@d;U%
private Page page; FL /395 <:
,5 ylrE
private List content; Tg-HR8}X
g(b:^_Nep
/** PAcbC|y
* The default constructor Di^7@}kQS
*/ H*H=a
public Result(){ g3h:oQCS
super(); ]CnqPLqL
} -:P`Rln
E979qKl
/** (UGmbRf&
* The constructor using fields c1 ~=
* w<o#/J9
* @param page &UV=<Az{
* @param content .>;}GsN&
*/ fN-y8
public Result(Page page, List content){ B'U;i5u4'
this.page = page; AgU 7U/yk
this.content = content; B|zVq=l~
} W4ygJL7 6
qbunP!
/** pRTdP/(OQ
* @return Returns the content. F VVpyB|
*/ wvuh
publicList getContent(){ B+pJWl8u
return content; Kd%>:E*
} D,<#pNO_
U*R
/** }w%W A&"W
* @return Returns the page. sP`
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*/ $mF(6<w
public Page getPage(){ F#
a)"$j;
return page; B*,Qw_3dG
} ,iYKtS3
;A3aUN;"I
/** Cjn)`Q8
* @param content 5"cYZvGkJ
* The content to set. >_m4
idq1
*/ RO9oO7S
public void setContent(List content){ Q&;d7A.@
this.content = content; i(pevu
} (46S^*
|-'.\)7:
/** h5>38Kd
* @param page &qP@WFl
* The page to set. t&^cYPRfY'
*/ Dj$W?dC"^
publicvoid setPage(Page page){ d O' apey
this.page = page; ;^cc-bLvF
} =w/S{yC
} 8g!C'5
]B'H(o
R<|
yS2[V,vS7
H{4/~Z
d J;y>_
2. 编写业务逻辑接口,并实现它(UserManager, aDreN*n
F,l%SQCyj
UserManagerImpl) ZR|cZH1}C
java代码: =nTNL .SX
|vLlEN/S
u}L;/1,B
/*Created on 2005-7-15*/ A!\-e*+W=
package com.adt.service; GSh~j-C'
zV<vwIUrr
import net.sf.hibernate.HibernateException; 9"RGf 1]
-Z/'kYj?U
import org.flyware.util.page.Page; 6d%|yl
~5xs$ub
import com.adt.bo.Result; |x ~<Dc>0*
i(l'f#
/** Jjgy;*hM
* @author Joa x(UOt;
*/ J91O$szA
publicinterface UserManager { F]"Hs>
lbg^ 2|o~~
public Result listUser(Page page)throws V.8pxD5s
mn;Wqb/
HibernateException; ,aLdW,<6
0k7kmDW
} ~=pAy>oV
3 IK+&hk
VSJ08Ngi
wV,l }Xb-
a!!>}e>Cj*
java代码: B2uLfi$q
'+Gy)@c
U $ bLt
/*Created on 2005-7-15*/ FKN!*}3
package com.adt.service.impl; ;%V%6:5
yN Bb(!u
import java.util.List; -UhGacw
IRxFcLk
import net.sf.hibernate.HibernateException; 1Z+\>~8
=rrbS8To=
import org.flyware.util.page.Page; fcC?1M[BP~
import org.flyware.util.page.PageUtil; >[U.P)7;
ny,a5zEnF
import com.adt.bo.Result; ;J)8#|
import com.adt.dao.UserDAO; 7rdPA9
import com.adt.exception.ObjectNotFoundException; mAFVjSa2
import com.adt.service.UserManager; npW1Z3n
v G7aT
/** ^z^ UFW
* @author Joa :<}.3 Q?&
*/ -}W`
publicclass UserManagerImpl implements UserManager { WRWcB
mu!hD^fw
private UserDAO userDAO; NSPa3NE
b[MdA|C%j
/** hR] AUH
* @param userDAO The userDAO to set. 8O)!{gB
*/ -5Km9X8
publicvoid setUserDAO(UserDAO userDAO){ .$k2.-k
this.userDAO = userDAO; m R? } gR
} V(Dn!Nz
>;;tX3(
/* (non-Javadoc) _c W(R,i
* @see com.adt.service.UserManager#listUser 6.!3g(w
H(1(H0Kj"
(org.flyware.util.page.Page) t[.wx.y&0
*/ G}lP'9/
public Result listUser(Page page)throws WG_20JdJY
N!`8-ap\^
HibernateException, ObjectNotFoundException { \3ZQ:E}5
int totalRecords = userDAO.getUserCount(); l5m5H,`
if(totalRecords == 0) MZ8jL,a^
throw new ObjectNotFoundException S4jt*]w5b
l^F%fIRp)
("userNotExist"); ^rDT+ x
page = PageUtil.createPage(page, totalRecords); rX*ATN
List users = userDAO.getUserByPage(page); M99gDN
returnnew Result(page, users); PKx ewd
} SseMTw:
&y}nd
7o
} g8_C|lVZi
E[FRx1^R9
f.o,VVYi
7sQw&yUL)
B~0L'8WzW
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 4+V+SD
%>cl0W3x
询,接下来编写UserDAO的代码: 8%$Vj
3. UserDAO 和 UserDAOImpl: _V9 O,"DDc
java代码: tkG0xRH
bs%lMa.o
C XQPbt[5
/*Created on 2005-7-15*/ 4@wH4H8
package com.adt.dao; F=29"1 ._
*hT1_
import java.util.List; 6PS #Zydb
Ua@rp3fr
import org.flyware.util.page.Page; o@o6<OP^
myVV5#{
import net.sf.hibernate.HibernateException; h9McC 3
_Gf.1Bsf@S
/** pLFJ"3IJB
* @author Joa n: ~y]
*/ da[u@eNrnX
publicinterface UserDAO extends BaseDAO { uF!3a$4]
yW$ja|^E
publicList getUserByName(String name)throws pX:FXzYQ
fC_dSM[{c
HibernateException; ;JcOm&d/hk
w2:!yQk_
publicint getUserCount()throws HibernateException; 2o`a^'Iw
5!55v
publicList getUserByPage(Page page)throws \;?=h
H(^O{JC]y!
HibernateException; gDw:Z/1X`
OAc*W<Q0
} 1$q>\
u7=jtB
VK*2`Z1
H:X=v+W
'JBf*p".
java代码: FTy`#*7Ul
x9#>0
4s
+$#YW5wy
/*Created on 2005-7-15*/ '8NKrI
package com.adt.dao.impl; 1@nGD<,.
%`%xD>![
import java.util.List; v5|X=B>&>
y@;4F n/
import org.flyware.util.page.Page; ,KlTitJl\+
|5wuYG
import net.sf.hibernate.HibernateException; 1Ftl1uf
import net.sf.hibernate.Query; JD^&d~n_
:<OInKE>Cx
import com.adt.dao.UserDAO; ?"p:6%GFz
=?`5n|A*
/** }}3*tn<6
* @author Joa 7-M$c7S
*/ Vrf+~KO7
public class UserDAOImpl extends BaseDAOHibernateImpl gY],
(*v
B)F2SK<@
implements UserDAO { +w-UK[p
;SzOa7
/* (non-Javadoc) n%w36_
* @see com.adt.dao.UserDAO#getUserByName # E'g{.N
Mj&f7IUO
(java.lang.String) b9[KdVsT6^
*/ [_jTy;E
publicList getUserByName(String name)throws TqNEU<S/t
yA%(!v5UT
HibernateException { EO'[AU% ~
String querySentence = "FROM user in class vgzNT4o
U9;C#9E
com.adt.po.User WHERE user.name=:name"; 5|ih>? C/(
Query query = getSession().createQuery (Al.hEs'
L&qzX)
(querySentence); DRD%pm(
query.setParameter("name", name); R1z\b~@"
return query.list(); l1~>{:mq
} =KwG;25hX
30Nya$$A=
/* (non-Javadoc) slEsSR'J]
* @see com.adt.dao.UserDAO#getUserCount() ]6{G;f$
*/ 29g("(}TK
publicint getUserCount()throws HibernateException { (=${@=!z
int count = 0; NDhHU#Q9
String querySentence = "SELECT count(*) FROM WigC'
,TD@s$2x
user in class com.adt.po.User"; #F5O>9hA
Query query = getSession().createQuery ^5biD9>M
}%EQ
(querySentence); Hw34wQX
count = ((Integer)query.iterate().next _pQ9q&i4
guv)[:cd;
()).intValue(); ,MwwA@,9-
return count; ZD1UMB0$4
} g2 uc+p
x%ZjGDF m
/* (non-Javadoc) "sz)~Q'W5
* @see com.adt.dao.UserDAO#getUserByPage 8#S|jBV
rr2'bf<]
(org.flyware.util.page.Page) b1>%%#
*/ >R/^|hnJ
publicList getUserByPage(Page page)throws ARW|wXhyf
?Zu=UVb
HibernateException { 3e"_R
String querySentence = "FROM user in class
o@_pV
U]dz_%CRP
com.adt.po.User"; "])X0z yM
Query query = getSession().createQuery *5 FSq
pB{QO4qn
(querySentence); z2og&|uT
query.setFirstResult(page.getBeginIndex()) pYJv|`+
.setMaxResults(page.getEveryPage()); &C3J6uCm+
return query.list(); /reSU 2
} i\G@ kJNnF
6q?C"\_
} no+{9Uf
%;9f$:U
!z X`M1J
/ocdAW`0
+Ij>\;vM"
至此,一个完整的分页程序完成。前台的只需要调用 02&m