Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 \+oQd=K@
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 ="1Ind@w!
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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 fa
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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 X:f UI4
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分页支持类: )al]*[lY
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java代码: er("wtM
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package com.javaeye.common.util; :;RMo2Tl
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import java.util.List; s[RAHU
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publicclass PaginationSupport { 4M=]wR;
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publicfinalstaticint PAGESIZE = 30; ?qv
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privateint pageSize = PAGESIZE; BA @lk+aW
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privateList items; [SjqOTon{
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privateint totalCount; gDQ^)1k
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privateint[] indexes = newint[0]; %^)fmu
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privateint startIndex = 0; DTX0
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public PaginationSupport(List items, int QGMV}y
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totalCount){ |%BOZT
setPageSize(PAGESIZE); 70yFaW
setTotalCount(totalCount); fF!Yp iI"
setItems(items); h/QXPdV
setStartIndex(0); qJf?o.Pv
} poc`q5i+
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public PaginationSupport(List items, int w1FcB$
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totalCount, int startIndex){ =}<IfNA
setPageSize(PAGESIZE); 3<e=g)F
setTotalCount(totalCount); Yj<a"
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setItems(items); 7m47rJyW4
setStartIndex(startIndex); bt@<
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} vOH4#
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public PaginationSupport(List items, int 3p$?,0ELH
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totalCount, int pageSize, int startIndex){ 0.Q
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setPageSize(pageSize); %HhBt5w
setTotalCount(totalCount); ,5P0S0*{
setItems(items); +N]J5Ve-`t
setStartIndex(startIndex); +WZX.D
} k`cfG\;r
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publicList getItems(){ =bAx,,D#
return items; cRC6 s8
} +X\FBvP&
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publicvoid setItems(List items){ 4V"E8rUL(
this.items = items; zF@/K`
} h7*J9[$
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publicint getPageSize(){ Ky`qskvu
return pageSize; =?5]()'*n
} i9:C4',sw0
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publicvoid setPageSize(int pageSize){ a)!o @
this.pageSize = pageSize; b35fs]}u-6
} xEa\f[.An
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publicint getTotalCount(){ f'F?MINJP
return totalCount; Q*GN`07@?d
} nF}vw |r>x
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publicvoid setTotalCount(int totalCount){ NYhB'C2
if(totalCount > 0){ 3h]g}&k
this.totalCount = totalCount; i}(LqcYU
int count = totalCount / Do9x
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pageSize; `T1
if(totalCount % pageSize > 0) g%aYDl
count++; W
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indexes = newint[count]; .zf~.R;>
for(int i = 0; i < count; i++){ gZVc 5u<
indexes = pageSize * &L3M]
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i; {aZ0;
} RCJ|P~*
}else{ IM*y|UHt
this.totalCount = 0; g/4[N{Xf
} T%+#xl
} D2#ZpFp"h
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publicint[] getIndexes(){ z xEL+ P
return indexes; }ZYd4h|g\z
} HH`'*$]7
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publicvoid setIndexes(int[] indexes){ )w em|:H
this.indexes = indexes; rDtY[
} K&u_R
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publicint getStartIndex(){ Z<oaK
return startIndex; *9
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} b\f
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publicvoid setStartIndex(int startIndex){ Nd4f^Y
if(totalCount <= 0) ]dVGUG8
this.startIndex = 0; 4>YR{
elseif(startIndex >= totalCount) ]U?^hZ_
this.startIndex = indexes cx,+k]9D
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[indexes.length - 1]; *YI98
elseif(startIndex < 0) ?PLPf>e
this.startIndex = 0; v4<nI;Ux
else{ ;T\%|O=Ke
this.startIndex = indexes D'>_I.
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[startIndex / pageSize]; H.P_]3f
} +:2klJ
} l03B=$
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publicint getNextIndex(){ ]Ee?6]bN
int nextIndex = getStartIndex() + goNG' o %|
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pageSize; s3N'02G
if(nextIndex >= totalCount) MBK^FR-K
return getStartIndex(); [>3./YH`
else #!B4 u?"m
return nextIndex; !"e5h`/ADM
} B^=-Z8
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publicint getPreviousIndex(){ UsG~row:!
int previousIndex = getStartIndex() - :]K4KFM
cdH>n)
pageSize; `%bypHeSp
if(previousIndex < 0) Xfc-UP|}
return0; q_lKKzA
else
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return previousIndex; ux-/>enc
} evJ4C#Pr
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} y8y5*e~A-)
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抽象业务类 sfH_5
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java代码: 5&g@3j]
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/** &<g|gsG`
* Created on 2005-7-12 f^ZRT@`O
*/ *tFHM &a
package com.javaeye.common.business; ?5__oT
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import java.io.Serializable; [Y/}
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import java.util.List; OF>mF~
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import org.hibernate.Criteria; z|uDy2
import org.hibernate.HibernateException; .#!lP/.eQP
import org.hibernate.Session; Y|m+dT6
import org.hibernate.criterion.DetachedCriteria; jwe *(k]z
import org.hibernate.criterion.Projections; *U- 4Sy
import h
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org.springframework.orm.hibernate3.HibernateCallback; t,Lrfv])
import udH7}K v
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org.springframework.orm.hibernate3.support.HibernateDaoS o 11jca|
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upport; `RT>}_j
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import com.javaeye.common.util.PaginationSupport; qbr$>xH
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public abstract class AbstractManager extends Hvauyx5T
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HibernateDaoSupport { G't$Qx,IC
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privateboolean cacheQueries = false; ;O5zUl-`
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privateString queryCacheRegion; 5ta `%R_
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publicvoid setCacheQueries(boolean m@j?za9s
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cacheQueries){ ja'T+!k
this.cacheQueries = cacheQueries; CkC^'V)
} uc{Ihw
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publicvoid setQueryCacheRegion(String !TH)
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queryCacheRegion){ QZwNw;$k*
this.queryCacheRegion = hag$GX'2k
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queryCacheRegion; Gu,wF(x7A
} \7eUw,~Q>
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publicvoid save(finalObject entity){ UgRiIQMq.
getHibernateTemplate().save(entity); ztY}5A2`
} s)t@ol
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publicvoid persist(finalObject entity){ ;d$rdFA_
getHibernateTemplate().save(entity); q q`4<0 I>
} nPtuTySG
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publicvoid update(finalObject entity){ }K>d+6qk5
getHibernateTemplate().update(entity); ?81c 4w
} @{e}4s?7od
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publicvoid delete(finalObject entity){ i"FtcP^
getHibernateTemplate().delete(entity); ~/U1xk%
} [aLI
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publicObject load(finalClass entity, B@))8.h]
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finalSerializable id){ gg/-k;@ Rf
return getHibernateTemplate().load iVr J Q
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(entity, id); 8d{0rqwNE
} L{\8!51L
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publicObject get(finalClass entity, S+6.ZZ9c
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finalSerializable id){ *a^(vo
return getHibernateTemplate().get B mb0cFQ
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(entity, id); m7V/zne
} ~=LE0. 3[
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publicList findAll(finalClass entity){ ) q4[zv9
return getHibernateTemplate().find("from B-Hrex]
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" + entity.getName()); UDFDJm$
} R w\gTo
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publicList findByNamedQuery(finalString h"W,WxL8
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namedQuery){ (mB&m@-N
return getHibernateTemplate |-ALklXr
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().findByNamedQuery(namedQuery); t}4,]ms
} Yh7t"=o
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publicList findByNamedQuery(finalString query, Dy&i&5E.-l
= svN#q5s
finalObject parameter){ lVa%$F{Pq
return getHibernateTemplate j;r-NCBnz
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Q
().findByNamedQuery(query, parameter); 4_lrg|X1
} 1I6px$^E\
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publicList findByNamedQuery(finalString query, .Hm>i
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finalObject[] parameters){ /nsX]V6i
return getHibernateTemplate pki%vRY
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().findByNamedQuery(query, parameters); FV!q!D
} ^\% (,KNo
8,%^
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publicList find(finalString query){ gJ{)-\
return getHibernateTemplate().find ;(%QD
3 >
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(query); ~~P5k:
} kTB0b*V
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publicList find(finalString query, finalObject 5DZ#9m/
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parameter){ uW{l(}0N
return getHibernateTemplate().find dT8S~-d%
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1
(query, parameter); }.(B}/$u
} bJ%h53
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public PaginationSupport findPageByCriteria |df Pki{
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(final DetachedCriteria detachedCriteria){ :Yl-w-oe
return findPageByCriteria =nS3p6>rZ
;'K5J9k
(detachedCriteria, PaginationSupport.PAGESIZE, 0); TdMruSY
} N+xP26D8
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public PaginationSupport findPageByCriteria {P./==^0
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(final DetachedCriteria detachedCriteria, finalint e T{ 4{
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startIndex){ RqrdAkg
return findPageByCriteria Avc%2+
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(detachedCriteria, PaginationSupport.PAGESIZE, 59A}}.@?m
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startIndex); ~mxO7cy5Cg
} 7}>E J
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public PaginationSupport findPageByCriteria [q-h|m
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(final DetachedCriteria detachedCriteria, finalint "8MF_Gu):
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pageSize, M }D}K\)
finalint startIndex){ 2ilQXy
return(PaginationSupport) vE?G7%,
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getHibernateTemplate().execute(new HibernateCallback(){ oc`H}Wvn
publicObject doInHibernate F41=b4/
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(Session session)throws HibernateException { ,"ZMRq
Criteria criteria = oPM96
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detachedCriteria.getExecutableCriteria(session); bd-L`={j
int totalCount = 7NGxa6wi
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((Integer) criteria.setProjection(Projections.rowCount 5;EvNu
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()).uniqueResult()).intValue(); TeM|:o
criteria.setProjection QWYJ*
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(null); Xv^qVn4
List items = i/4>2y9/F4
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criteria.setFirstResult(startIndex).setMaxResults ga +dt
8ib:FF(= u
(pageSize).list(); a~w$#fo"`f
PaginationSupport ps = L8B!u9%
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new PaginationSupport(items, totalCount, pageSize, V,njO{Q
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startIndex); fHFE){
return ps; z}
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} k(HUUH_z
}, true); ?@86P|19
} %ET+iIhK
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public List findAllByCriteria(final XL^GZ
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DetachedCriteria detachedCriteria){ 2+XAX:YD
return(List) getHibernateTemplate ;V!D:5U
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().execute(new HibernateCallback(){ |6-nbj
publicObject doInHibernate 2>%=U~5
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(Session session)throws HibernateException { <hyKu
Criteria criteria = 75lA%|
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detachedCriteria.getExecutableCriteria(session); i
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return criteria.list(); *.[.
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} 'w aaw_>b
}, true); \FaP|28h
} @0''k
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public int getCountByCriteria(final {JLtE{
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DetachedCriteria detachedCriteria){ TWTb?HP
Integer count = (Integer) f o3}W^0
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getHibernateTemplate().execute(new HibernateCallback(){ d=/F}yP~?s
publicObject doInHibernate
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(Session session)throws HibernateException { {qVZNXDn
Criteria criteria = z1a7*)8P
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detachedCriteria.getExecutableCriteria(session); QT}tvm@PMq
return o mx=
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criteria.setProjection(Projections.rowCount %]i15;{X
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()).uniqueResult(); 8ao _i=&x
} UiNP3TJ'L
}, true); *T1_;4i
return count.intValue(); DY*N|OnqJ
} EU#^7
} %C]>9."
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用户在web层构造查询条件detachedCriteria,和可选的 /-s6<e!
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 DmcZta8n]
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PaginationSupport的实例ps。 kx^/*~ex
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ps.getItems()得到已分页好的结果集 y();tsWqc
ps.getIndexes()得到分页索引的数组 rm_Nn8p,
ps.getTotalCount()得到总结果数 wd6owr
ps.getStartIndex()当前分页索引 &^nGtW%a 9
ps.getNextIndex()下一页索引 vDvFL<`vmD
ps.getPreviousIndex()上一页索引 nk:)j:fr
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 :Dp0?&_
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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 w-jVC^C]
)/P}?`I
一下代码重构了。
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我把原本我的做法也提供出来供大家讨论吧: ?7A>+EY
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首先,为了实现分页查询,我封装了一个Page类: GvAb`c=
java代码: =~gvZV-<
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/*Created on 2005-4-14*/ Xa&kIq}(g
package org.flyware.util.page; /wv0i3_e
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/** '%;m?t%q
* @author Joa Dp:BU|r
* vQ.R{!",>
*/ EM_d8o)`B
publicclass Page { gM]:Ma
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/** imply if the page has previous page */ (k P9hcV
privateboolean hasPrePage; e+|sSp A
\. S/|
/** imply if the page has next page */ JGZBL{8
privateboolean hasNextPage; V[V[~;Py
^rz_f{c]-
/** the number of every page */ $VR{q6[0S?
privateint everyPage; ->jDb/a{C
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/** the total page number */ =MWHJ'3-/
privateint totalPage; 8XaQAy%d]
.Y|!:t|
/** the number of current page */ O&&~NXI\
privateint currentPage; 4e
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q>+
/** the begin index of the records by the current ^^Vg~){4
F[MFx^sT{
query */ R-14=|7a-
privateint beginIndex; j1Ezf=N6`
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/** The default constructor */ <naz+QK'
public Page(){ SWLo|)@[/
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} ?cZlN!
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/** construct the page by everyPage $Q0n
* @param everyPage 31)&vf[[
* */ P2Y^d#jO
public Page(int everyPage){ !9x}
this.everyPage = everyPage; h];I{crh
} 2SLU:=<3
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/** The whole constructor */ n !(F, b
public Page(boolean hasPrePage, boolean hasNextPage, >dT*rH 3w
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int everyPage, int totalPage, ^Dx&|UwiZa
int currentPage, int beginIndex){ TC"<g
this.hasPrePage = hasPrePage; $xQL]FmS
this.hasNextPage = hasNextPage;
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this.everyPage = everyPage; 05[SC}MCA
this.totalPage = totalPage; %)wjR/o
this.currentPage = currentPage; \v/[6&|X0s
this.beginIndex = beginIndex; Ss`LLq0LO
} _f{{( 7
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/** r*Xuj=
* @return 28nFRr
* Returns the beginIndex. SAz
*/ ~K=b\xc^
publicint getBeginIndex(){ Mp]rUPK
return beginIndex; pJ{Y
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} < vP=zk
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/** .^g p?
* @param beginIndex 'PHl$f*k
* The beginIndex to set. +h$
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*/ _-\#i
publicvoid setBeginIndex(int beginIndex){ 4I7>f]=)
this.beginIndex = beginIndex; #/]nxW.S
} ,vDbp?)'U
d'2A,B~_*
/** HTtnXBJ)*H
* @return w>YDNOk
* Returns the currentPage. <uJ@:oWG7
*/ qWw=8Bq
publicint getCurrentPage(){ o(HbGHIP
return currentPage; yHGADH0B
} pXUSLs
(#'>(t(4
/** @@%ataUSBT
* @param currentPage q*KAk{kR(v
* The currentPage to set. 16 $B>
*/ =QsYXK7Mn4
publicvoid setCurrentPage(int currentPage){ o}!PQ#`M
this.currentPage = currentPage; cu6Opq9
} DrQ`]]jj7
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/** [!z,lY>
* @return u4j5w
* Returns the everyPage. B1STG L`nK
*/ ix$bRdl
publicint getEveryPage(){ _j3f Ar(V
return everyPage; M`>E|"<
} 626r^c=
rGO8!X 3d
/** :-'qC8C
* @param everyPage ]{iQ21`a-
* The everyPage to set. #*}+J3/
*/ "}!G!k:
publicvoid setEveryPage(int everyPage){ #`IN`m|
this.everyPage = everyPage; MJvp6n
} Vc2`b3"Br
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/** #S(Hd?34,
* @return &o*A{
* Returns the hasNextPage. :r[`.`
*/ wbHb;]
publicboolean getHasNextPage(){ TNth
return hasNextPage; +0~YP*I`/
} d5.4l&\u
pFXEu=$3
/** Y7aqO5
* @param hasNextPage /NlGFO*Z
* The hasNextPage to set. yw!{MO
*/ ]3gSQ7
publicvoid setHasNextPage(boolean hasNextPage){ Qd-A.{[h
this.hasNextPage = hasNextPage;
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} dscgj5b1~
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/** <m m[S
* @return i$@:@&(~Y
* Returns the hasPrePage. T|p"0b A
*/ yZRzIb_
publicboolean getHasPrePage(){ N$DkX)Z
return hasPrePage; "{n&~H`
} ^_6|X]tz1T
/mMV{[
/** :svqE+2
* @param hasPrePage g{Rd=1SK]
* The hasPrePage to set. OPi0~s
*/ ,>M[@4`,U
publicvoid setHasPrePage(boolean hasPrePage){ U17d>]ka
this.hasPrePage = hasPrePage; Th%zn2R B
} nEfK53i_
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/** JVJMgim)0
* @return Returns the totalPage. S 5U;#H
* TV:9bn?r)
*/ XuTD\g3)
publicint getTotalPage(){ C+]I@Go'Tk
return totalPage; ~?dI*BZ)]
} ~@!bsLSMU
&L:!VL{I
/** %C0Dw\A*:
* @param totalPage N;R^h? '
* The totalPage to set. [RL9>n8f
*/ ,I9bNO,%JK
publicvoid setTotalPage(int totalPage){ BWNi [^]
this.totalPage = totalPage; lFkR=!?=
} 7,MR*TO,
s*4dxnS_8
} 3
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上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 . me;.,$#
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个PageUtil,负责对Page对象进行构造: ^pS~Z~[d/
java代码: 3'Rx=G'
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/*Created on 2005-4-14*/ z{543~Og59
package org.flyware.util.page; ni<(K
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import org.apache.commons.logging.Log; E$e5^G9
import org.apache.commons.logging.LogFactory; fJ\[*5eiS
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/** [;N'=]`
* @author Joa "7
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* yu|>t4#GT
*/ >l m&iF3y
publicclass PageUtil { QPx^_jA
t-AmX)$
privatestaticfinal Log logger = LogFactory.getLog rOYx
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(PageUtil.class); GY*p?k<i
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/** 54,er$$V
* Use the origin page to create a new page Q59suL
* @param page ?0.NIu,,o
* @param totalRecords + 3gp%`c4
* @return =wJX0A|
*/ @WhHUd4s
publicstatic Page createPage(Page page, int =M1I>
{:s f7
totalRecords){ qK+5NF|
return createPage(page.getEveryPage(), Sdo-nt
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page.getCurrentPage(), totalRecords); mDWG7 Asp
} \['Cj*e k
# _1`)VS
/** +|v90ed
* the basic page utils not including exception 0K+ne0I
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handler =]t|];c%
* @param everyPage W^Yxny
* @param currentPage F
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* @param totalRecords %>yL1BeA4
* @return page ' QG?nu
*/ 1\Xw3prH
publicstatic Page createPage(int everyPage, int }C:r9?T
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currentPage, int totalRecords){ ~&T~1xsFJ
everyPage = getEveryPage(everyPage);
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currentPage = getCurrentPage(currentPage); Ri{=]$
int beginIndex = getBeginIndex(everyPage, \RiP
1x)J[fyId
currentPage); "g|#B4'e
int totalPage = getTotalPage(everyPage, ]lbuy7xj63
2iOV/=+
totalRecords); -~0^P,yQ
boolean hasNextPage = hasNextPage(currentPage, =&]L00u.
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totalPage); XUYtEf
boolean hasPrePage = hasPrePage(currentPage); A<{{iBEI`
r"
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returnnew Page(hasPrePage, hasNextPage, L#J1b!D&<6
everyPage, totalPage, fl(wV.Je|
currentPage, t!XwW$@
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beginIndex); o4X{L`m
} Wc#24:OKe3
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privatestaticint getEveryPage(int everyPage){ JI}'dU>*U:
return everyPage == 0 ? 10 : everyPage; khe}*y
} u[YGm:}
L_T5nD^D
privatestaticint getCurrentPage(int currentPage){
)2.Si#
return currentPage == 0 ? 1 : currentPage; M-71 1|eGI
} #] QZ
wj,=$RX
privatestaticint getBeginIndex(int everyPage, int +whDU2 "
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currentPage){ py4 h(04u
return(currentPage - 1) * everyPage; Xhm
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} DUS6SO
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privatestaticint getTotalPage(int everyPage, int ,F|f. 7;
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totalRecords){ HtFDlvdy]
int totalPage = 0; [WmM6UEVS
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if(totalRecords % everyPage == 0) h0$iOE
totalPage = totalRecords / everyPage; &8H'eAA
else l**X^+=$
totalPage = totalRecords / everyPage + 1 ; t_^4`dW`
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return totalPage; ~}P,.QQ
} ]G\}k
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privatestaticboolean hasPrePage(int currentPage){ I,tud!p`
return currentPage == 1 ? false : true; {FkF
} ^W^OfY
@dKTx#gZ
privatestaticboolean hasNextPage(int currentPage, 7I}uZ/N
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int totalPage){ eFgA 8kY)
return currentPage == totalPage || totalPage == 7dWS
,bi^P>X
0 ? false : true;
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} TbU#96"~.
4 KiY6)
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} ~$'awY
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上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 @{Q4^'K"
S[gx{Bxiw
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 7#XzrT]
qGo.WZ$
做法如下: IxU/?Zm
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 0B2t"(&
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的信息,和一个结果集List: %J(:ADu]
java代码: W\3X=@|u)
Y<OFsWYY
nlP;nl W
/*Created on 2005-6-13*/ ~ljXzD93Z
package com.adt.bo; 0J9x9j`&j
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import java.util.List; ?,mmYW6TjB
1}x%%RD_
import org.flyware.util.page.Page; HJ"GnZp<
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/** HPl<%%TI
* @author Joa [n@]
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*/ u`W2+S
publicclass Result { SUiOJ[5,
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private Page page; (`^1Y3&2
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private List content; X?O[r3<
@d'j zs
/** H_a[)DT
* The default constructor zhQJy?>'m
*/ I7onX,U+
public Result(){ B,@i
super(); (PLUFT
} m
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/** ch]IzdD
* The constructor using fields #a#F,ZT
* KlEpzJ98
* @param page 7CysfBF0g
* @param content -7ep{p-
*/ sJZiI}Xc
public Result(Page page, List content){ >4TO=i
this.page = page; i-1op> Y
this.content = content; `5*}p#G
} =_CzH(=f#
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/** Wtnfa{gP%
* @return Returns the content. F?0Ykjh3
*/ OUnA;_
publicList getContent(){ [^iN}Lz
return content; j 7B!h|
} W/N7vAx X
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/** ).O)p9
* @return Returns the page. KNl$3nX
*/ inL(X;@yo
public Page getPage(){ "]*tLL:`
return page; 0-gAyiKx?
} @7}W=HB
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/** Uo49*Mr
* @param content ?,/ }`3Vw
* The content to set.
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*/ kJU2C=m@e2
public void setContent(List content){ " bG2:
this.content = content; PT
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} `[A];]
+@UV?"d
/** @ Qe0! (_=
* @param page btB%[]
* The page to set. 9c],<;{'
*/ 637:
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publicvoid setPage(Page page){ ceA9){
this.page = page; }V>T M{
} U$g?!Yl0
} f);FoVa6
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2. 编写业务逻辑接口,并实现它(UserManager, =4!mAo}
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UserManagerImpl) ]:;&1h3'7
java代码: iU-j"&L5
jPeYmv]
f1? >h\F8
/*Created on 2005-7-15*/ WIOV2+
package com.adt.service; ICCc./l|
MD]>g>
import net.sf.hibernate.HibernateException; pAEx#ck
~[: 2I
import org.flyware.util.page.Page; *Ex|9FCt$
*j=%
#
import com.adt.bo.Result; GbyJ:
Ac6=(B
/** %y@AA>x!
* @author Joa ysN3
*/ 2c}E(8e]
publicinterface UserManager { Rcv9mj]l
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public Result listUser(Page page)throws 0(Ij%Wi,
$'TM0Yu,
HibernateException; 49P4b<1
^.tg 7%dJ
} $kgVa^
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lr?;*f^3
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L=/$
Cw%{G'O
java代码: c,22*.V/
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0V]s:S
/*Created on 2005-7-15*/ ]Dzlp7Y}
package com.adt.service.impl; =sFTxd_"iQ
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import java.util.List; wBzC5T%,
]9L
oZ)
import net.sf.hibernate.HibernateException; fVwUe _Y
f::Dx1VcX
import org.flyware.util.page.Page; 'yth'[
import org.flyware.util.page.PageUtil; B *vM0
$(9U @N9E
import com.adt.bo.Result; E4!Fupkpf
import com.adt.dao.UserDAO; \jA~9
import com.adt.exception.ObjectNotFoundException; +"(jjxJm
import com.adt.service.UserManager; !BI;C(,RL
/(T?j!nPE
/** S'14hk<
* @author Joa Qd6F H2Pl
*/ WHI`/FM
publicclass UserManagerImpl implements UserManager { =xrv~
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private UserDAO userDAO; zQA`/&=Y
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/** OB7hlW
* @param userDAO The userDAO to set. F?cK-.
*/ }Lv;!
publicvoid setUserDAO(UserDAO userDAO){ 2tLJU Z1
this.userDAO = userDAO; n(Uyz`qE
} :4s1CC+@\
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/* (non-Javadoc) 1}37Q&2
* @see com.adt.service.UserManager#listUser M;NX:mX9
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(org.flyware.util.page.Page) _6Ha
*/ 9kojLqCT
public Result listUser(Page page)throws 7KPwQ?SjT
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HibernateException, ObjectNotFoundException { V1?]|HTQcT
int totalRecords = userDAO.getUserCount(); kLY^!
if(totalRecords == 0) ca}2TT&t
throw new ObjectNotFoundException -+5>|N#
{t!!Uz 7
("userNotExist"); Zov~B-Of:
page = PageUtil.createPage(page, totalRecords); .o8t+X'G
List users = userDAO.getUserByPage(page); &R siVBA
returnnew Result(page, users); q =Il|Nb>
} H[UlY?&+
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} Wf<LR3
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其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 w:l"\Tm
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询,接下来编写UserDAO的代码: W l16`9
3. UserDAO 和 UserDAOImpl: -DCbko
java代码: yBRC*0+Vy
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/*Created on 2005-7-15*/ 4~=l}H>&
package com.adt.dao; 0ksa
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import java.util.List; -F92 -jBM4
66 Tpi![
import org.flyware.util.page.Page; 7?t6UPf
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r>@
import net.sf.hibernate.HibernateException; f X)#=c|5
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/** Hefg[$m
* @author Joa [:V$y1
*/ dTtSUA|V7"
publicinterface UserDAO extends BaseDAO { };g"GNy
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publicList getUserByName(String name)throws Jo}eeJ;k
vFsLY
HibernateException; ??T#QQ
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publicint getUserCount()throws HibernateException; Z6pUZ[j,
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publicList getUserByPage(Page page)throws "\=U)CJ
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HibernateException; \;-|-8Q
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} 05k0n E
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@A5?3(e
java代码: C
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ERt{H3eCcJ
4e1Y/
Xq`
/*Created on 2005-7-15*/ PT9*)9<L
package com.adt.dao.impl; ~nPtlrQa#*
U?=Dg1
import java.util.List; f9\X>zzB2|
hL5|69E
import org.flyware.util.page.Page; $\! 7 {6a
:h V7>
rr
import net.sf.hibernate.HibernateException; x=jK:3BF
import net.sf.hibernate.Query; kxRV)G
Bw{I;rW{2
import com.adt.dao.UserDAO; ,=:D
(khL-F
/** 6DWgl$[[
* @author Joa T n}s*<=V
*/ 7`YEH2
public class UserDAOImpl extends BaseDAOHibernateImpl !L8#@BjU
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implements UserDAO { 2dzrRH
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/* (non-Javadoc) Ydy9
* @see com.adt.dao.UserDAO#getUserByName TW>WHCAm
%!L9)(}"
(java.lang.String) 0C*7K?/
*/ -o.:P>/
publicList getUserByName(String name)throws +t:0SRSt
evJ.<{M
HibernateException {
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String querySentence = "FROM user in class W 8!Qv8rf
BV+ Bk+
com.adt.po.User WHERE user.name=:name"; _\HQvH
Query query = getSession().createQuery zNuJj L
;]jNk'oa
(querySentence); F.v{-8GV
query.setParameter("name", name); T${Q.zHY[!
return query.list(); zZC9\V}R
} 63~
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"v4B5:bmqW
/* (non-Javadoc) kn"(A.R
* @see com.adt.dao.UserDAO#getUserCount() Ji 0
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*/ E`k@{*Hn&
publicint getUserCount()throws HibernateException { @k/NY*+
int count = 0; ^Js9 s8?$
String querySentence = "SELECT count(*) FROM [\b0Lem
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user in class com.adt.po.User"; t3Y:}%M
Query query = getSession().createQuery f8.gT49I
fe#\TNeQJ[
(querySentence); V}NbuvDB@
count = ((Integer)query.iterate().next W1FI mlXS
pQ<Y:-`c
()).intValue(); CoAvSw
return count; A7hVHxNJ-
} +V^;.P</
klR|6u]%
/* (non-Javadoc) VEw"
* @see com.adt.dao.UserDAO#getUserByPage Yr=Y@~ XL
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(org.flyware.util.page.Page) y[_Q-
*/ Uwx
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publicList getUserByPage(Page page)throws
}sO&. ME
1&(V
HibernateException { A4<Uu~
String querySentence = "FROM user in class %O;bAC_M
bl(RyAgA
com.adt.po.User"; 1!T1Y,w
Query query = getSession().createQuery WYYa/,{9.
Y6L~K?
(querySentence); @)&=%
query.setFirstResult(page.getBeginIndex()) be^6i:
.setMaxResults(page.getEveryPage()); 4G>H
return query.list(); gH7|=W
} =j*$
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fG(SNNl+D
} c[1oww
4l45N6"
Nf"r4%M<6
<r`2)[7N
q Xe8Kto
至此,一个完整的分页程序完成。前台的只需要调用 k<{{*
-f>%+<