Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 Y~-P9
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 f/%QMhM:
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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 Nr0}*8#j
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自于Quake Wang的javaeye-core包的相应类,然后又做了很多修改 {h}e 9
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。 >WYradLUi
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分页支持类: nB#XQ8Nzx^
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java代码: F@kd[>/[
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package com.javaeye.common.util; 2sahb#e
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import java.util.List; bv4G!21]*;
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publicclass PaginationSupport { uxD$dd?
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publicfinalstaticint PAGESIZE = 30; L
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privateint pageSize = PAGESIZE; <P1x3
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privateList items; "'*w_H0
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privateint totalCount; J=AF`[
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privateint[] indexes = newint[0]; /nVGr]t_pj
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privateint startIndex = 0; _*LgpZ-2(
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public PaginationSupport(List items, int -DE?L,9X9
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totalCount){ hScC<=W
setPageSize(PAGESIZE); .{
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setTotalCount(totalCount); @_C?M5v
setItems(items); *MZa|Xy
setStartIndex(0); oTLpq:9J
} y-#01Z
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public PaginationSupport(List items, int 1_6oM/?'
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totalCount, int startIndex){ ?Y\hC0a60
setPageSize(PAGESIZE); -5sKJt]+i
setTotalCount(totalCount); .%T.sQ
setItems(items); S_dM{.!Z(,
setStartIndex(startIndex); XPsRa[08WK
} j55;E
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public PaginationSupport(List items, int Ee 15Y$1
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totalCount, int pageSize, int startIndex){ WHKe\8zWq
setPageSize(pageSize); ?)?}^
setTotalCount(totalCount); #Zt(g( T
setItems(items); e|S_B*1*0
setStartIndex(startIndex); iFkXt<_A
} _2E*
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publicList getItems(){ fsz:A"0H
return items; 9@yi
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} .p$tb2%r
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publicvoid setItems(List items){ 6Us*zKgW
this.items = items; U3b&/z|b?
} dxK3462
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publicint getPageSize(){ :DoE_
return pageSize; RgTrj
} o%sx(g=q6
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publicvoid setPageSize(int pageSize){ II)
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this.pageSize = pageSize; %+0V0.
} 8m"jd+
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publicint getTotalCount(){ =dDr:Y<@*
return totalCount; r0(* ]K:.
} ]o3K
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publicvoid setTotalCount(int totalCount){ |cIv&\ x
if(totalCount > 0){ 8c^Hfjr0
this.totalCount = totalCount; ^< wn
int count = totalCount / x#c%+
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pageSize; iTIYq0u|#R
if(totalCount % pageSize > 0) E2u9>m4_J
count++; 1yV+~)by3
indexes = newint[count]; EUjA-L(
for(int i = 0; i < count; i++){ jSd[
indexes = pageSize * E)z=85;_p
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i; gOLN7K-)
} jU0E=;1
}else{ Q7 @oAeNd
this.totalCount = 0; "^NsbA+
} 4I!g?Moh
} Z)'gj
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publicint[] getIndexes(){ /wT<p
return indexes; J1g+H2
} U\GuCw
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publicvoid setIndexes(int[] indexes){ H?cJ'Q,5
this.indexes = indexes; br%l>Y\"
} x".!&5
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publicint getStartIndex(){ Q%!Dk0-)
return startIndex; %_%BbQf
} E(g$f.9
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publicvoid setStartIndex(int startIndex){ L6Io u
if(totalCount <= 0) $(+#$F<eo+
this.startIndex = 0; V[2}
elseif(startIndex >= totalCount) 4=qZ Z>[t
this.startIndex = indexes 4~i?xo=;v
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[indexes.length - 1]; yZQcxg%
elseif(startIndex < 0) PWk\#dJN&
this.startIndex = 0; &M{;[O{
else{ }*?,&9/_)
this.startIndex = indexes Fxv5kho
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[startIndex / pageSize]; nZ %%{#T7
} DPr~DO`b
} %00cC~}4
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publicint getNextIndex(){ )f,9 h
int nextIndex = getStartIndex() + %&j\:X~A
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pageSize; t-Uo
if(nextIndex >= totalCount) #\Zr$?t|V
return getStartIndex(); TyY%<NCIb
else BlfadM;
return nextIndex; |8?e4yVd
} l1vI
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publicint getPreviousIndex(){ K.Tob,5`
int previousIndex = getStartIndex() - i
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pageSize; n?*r, )'
if(previousIndex < 0) d9up!
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return0; K5!OvqzG
else dngG=
return previousIndex; M $f6.j
} !<>*|a
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} \,ne7G21j
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抽象业务类 gI!d*]{BP
java代码: SHT`
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/** 6aLRnH"Ud
* Created on 2005-7-12 0D Lw
*/ ohjl*dw
package com.javaeye.common.business; 2Z>8ROv^X
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import java.io.Serializable; 25 cJA4
import java.util.List; (hEg&@
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import org.hibernate.Criteria; \q\"=
import org.hibernate.HibernateException; &0i$Y\g
import org.hibernate.Session; .N7<bt@~)
import org.hibernate.criterion.DetachedCriteria; [&g"Z"
import org.hibernate.criterion.Projections; >gDeuye
import WLA&K]
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org.springframework.orm.hibernate3.HibernateCallback; fN/;BT
import (&Rql7](8
7>=
org.springframework.orm.hibernate3.support.HibernateDaoS 0SQrz$y
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upport; bh(}f.@
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import com.javaeye.common.util.PaginationSupport; @]!9;?so
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public abstract class AbstractManager extends D|*yeS4>
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HibernateDaoSupport { D5!#c-Y-
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privateboolean cacheQueries = false; 70'gVCb
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privateString queryCacheRegion; `NTtw;%Y
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publicvoid setCacheQueries(boolean ex
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cacheQueries){ {1qr6P,"
this.cacheQueries = cacheQueries; 1[J|AkN
} F2Y!aR
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publicvoid setQueryCacheRegion(String Np i)R)
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queryCacheRegion){ _a f $0!
this.queryCacheRegion = cUr!U\X[
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queryCacheRegion; TW|- 0
} vZW[y5
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publicvoid save(finalObject entity){ J.'%=q(Sb
getHibernateTemplate().save(entity); ANNVE},
} fs?H
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publicvoid persist(finalObject entity){ ^`B;SSV
getHibernateTemplate().save(entity); =H3tkMoi2
} Oi zj|'
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publicvoid update(finalObject entity){ ;rF[y7\
getHibernateTemplate().update(entity); r<4j;"lQK
} 6ypLE@Mk
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publicvoid delete(finalObject entity){ 1=7ASS9
getHibernateTemplate().delete(entity); UhrRB
} m"'}{3$%
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publicObject load(finalClass entity, !\$V?*p7
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finalSerializable id){ _m[DieR
return getHibernateTemplate().load o.kDOqd
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(entity, id); &q@brX<,=
} .6T0d
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publicObject get(finalClass entity, Rk[a|T &
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finalSerializable id){ q2s0g*z
return getHibernateTemplate().get IRwtM'%0
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(entity, id); k|\M(Z*(P
} V.z8
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publicList findAll(finalClass entity){ ]ly" K!1,
return getHibernateTemplate().find("from CGzu(@dd\
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" + entity.getName()); SJ<v< B
} atF#0*e>
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publicList findByNamedQuery(finalString S<-nlBs.
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namedQuery){ aZCq{7Xs
return getHibernateTemplate W7
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().findByNamedQuery(namedQuery); vXRY/Zzj1
} KyfH8Na?
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publicList findByNamedQuery(finalString query, e).;;0
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finalObject parameter){ ]/H6%"CTa
return getHibernateTemplate as!a!1
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().findByNamedQuery(query, parameter); \0d'y#Gp*
} tV`=o$`
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publicList findByNamedQuery(finalString query, E "}@SaB-
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finalObject[] parameters){ |5tZ*$nGa
return getHibernateTemplate (or"5}\6-
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().findByNamedQuery(query, parameters); [#q]B=JB
} -PAEJn5$O
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publicList find(finalString query){ p/?o^_s
return getHibernateTemplate().find 3_Xu3hNH!
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(query); F{!pii5O9
} w\YS5!P,V
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publicList find(finalString query, finalObject Xs2 jR14`
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parameter){ %Qlc?Wl:
return getHibernateTemplate().find %:d7Ts&?Z
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(query, parameter); %z-*C'j5H
} HyU: BW;
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public PaginationSupport findPageByCriteria =I546($
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(final DetachedCriteria detachedCriteria){ UGI<V!
return findPageByCriteria w CB*v<*
v={{$=/t
(detachedCriteria, PaginationSupport.PAGESIZE, 0); KDq="=q
} :86:U 0^
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public PaginationSupport findPageByCriteria e))L&s
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(final DetachedCriteria detachedCriteria, finalint {9U!0h-2"
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startIndex){ <[cpaZT,
return findPageByCriteria #mw!_]
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(detachedCriteria, PaginationSupport.PAGESIZE, < ,*\t
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startIndex); eMC^ORdY
} 8YQuq.(>a
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public PaginationSupport findPageByCriteria fUkqhqe
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(final DetachedCriteria detachedCriteria, finalint w3(|A> s3
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pageSize, ],pB:=
finalint startIndex){ ^w\22 Q
return(PaginationSupport) #f2k*8"eAF
8m?(* [[
getHibernateTemplate().execute(new HibernateCallback(){ .Q,"gsY
publicObject doInHibernate \D? '.Wo%
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(Session session)throws HibernateException { D4!;*2t
Criteria criteria = V|97;
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detachedCriteria.getExecutableCriteria(session);
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int totalCount = @%Ld\8vdfJ
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((Integer) criteria.setProjection(Projections.rowCount %Hbq3U30
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Ot=C=
()).uniqueResult()).intValue(); WzN c=@[W
criteria.setProjection ^?`fN'!p
RW. qw4
(null); C
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List items = tb+gCs'D
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criteria.setFirstResult(startIndex).setMaxResults SN}K=)KF#
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(pageSize).list(); S{+t>en
PaginationSupport ps = x|0C0a\"A
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new PaginationSupport(items, totalCount, pageSize, f=F:Af!
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startIndex); 2d[q5p
return ps; Xxg|01
} V/ G1C^'/
}, true); 73cb1kfPd
} Trv}YT.
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public List findAllByCriteria(final i<^X z
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DetachedCriteria detachedCriteria){ )}@D\(/@
return(List) getHibernateTemplate ~v;I>ij
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().execute(new HibernateCallback(){ Vke<; k-
publicObject doInHibernate *(OG+OkC
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(Session session)throws HibernateException { oe|#!SM(
Criteria criteria = `q*[fd1u.
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detachedCriteria.getExecutableCriteria(session); 5~[7|Y
return criteria.list(); _nMd
} 9Y:I)^ek
}, true); 3x+lf4"
} ZbYC3_7w
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public int getCountByCriteria(final }
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DetachedCriteria detachedCriteria){ 4E^ ?}_$
Integer count = (Integer) k:Pn.<
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getHibernateTemplate().execute(new HibernateCallback(){ 0~qc,-)3
publicObject doInHibernate /mex{+p>tO
> <YU'>%
(Session session)throws HibernateException { @|b-X? `
Criteria criteria = eP-|3$
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detachedCriteria.getExecutableCriteria(session); `}Zqmfs
return 5qz,FKx5
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criteria.setProjection(Projections.rowCount 9eMle?pF
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()).uniqueResult(); [Yt{h9
} hC\
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}, true); (s3k2Z
return count.intValue(); \?xM%(:<Q
} V"YeF:I
} A(FnU:
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用户在web层构造查询条件detachedCriteria,和可选的 Lnh=y2
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 2RkW/)A9
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PaginationSupport的实例ps。 6.D|\;9{c
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ps.getItems()得到已分页好的结果集 X4V>qHV72
ps.getIndexes()得到分页索引的数组 5#DMizv6
ps.getTotalCount()得到总结果数 bJ^h{]
ps.getStartIndex()当前分页索引 \Bo%2O%4
ps.getNextIndex()下一页索引 !D??Y^6bI
ps.getPreviousIndex()上一页索引 Nz
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 h&>3;Lj
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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 *[[Gu^t^!
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一下代码重构了。 E4X6f
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我把原本我的做法也提供出来供大家讨论吧: 9;@p2t*v
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首先,为了实现分页查询,我封装了一个Page类: q1}!O kr"2
java代码: xuioU
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/*Created on 2005-4-14*/ &hYgu3O
package org.flyware.util.page; 7gC?<;\0
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/** , PlH|
* @author Joa ,H]%4@]|o
* S/]\GG{
*/ gb_Y]U
publicclass Page { ,X@o@W+L
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/** imply if the page has previous page */ j?K$w`
privateboolean hasPrePage; 6<lo0PQ"Z
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/** imply if the page has next page */ y]h0c<NP
privateboolean hasNextPage; !..<_qfw
: K|
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/** the number of every page */ 'PF>#X''
privateint everyPage; 5u!\c(TJ+
c*IrZm
/** the total page number */ Pq /5Dy
privateint totalPage; (0 T!-hsP
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/** the number of current page */ (D>_O$o
privateint currentPage; ,L<JG
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/** the begin index of the records by the current rB[J*5v
!Z$d<~Mq q
query */ JEto_&8,C
privateint beginIndex; N~)-\T:ap
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/** The default constructor */ bzi"7%c
public Page(){ "Rj
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} v)
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/** construct the page by everyPage '09|Y#F
* @param everyPage ~gI%lORqN
* */ dFz"wvu` o
public Page(int everyPage){ 9?l a5
this.everyPage = everyPage; dtTn]}J
} 3TwjC:Yhv2
VF?H0}YSHb
/** The whole constructor */ '/>Mr!H#
public Page(boolean hasPrePage, boolean hasNextPage, 6 >kU Lp
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int everyPage, int totalPage, CS[]T9|_
int currentPage, int beginIndex){
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this.hasPrePage = hasPrePage; a/J<(sak~X
this.hasNextPage = hasNextPage; :c*"Dx'D
this.everyPage = everyPage; 2-4N)q
this.totalPage = totalPage; rq%]CsRY5
this.currentPage = currentPage; zhn?;Fi
this.beginIndex = beginIndex; /oPW0of
} w#.3na
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/** #T7v]@K67
* @return <6Q^o[L
* Returns the beginIndex. a#p+.)Wm
*/ ,.)wCZ,wca
publicint getBeginIndex(){ Z)rW>I
return beginIndex; Ks.b).fH
} Pe%[d[k
[:X@|,1V!L
/** qTuR[(
* @param beginIndex Mq>
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* The beginIndex to set. b31$i 5{
*/ w.m8SvS&b
publicvoid setBeginIndex(int beginIndex){ r^
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this.beginIndex = beginIndex; _}R$h=YD
} _pdKcE\X
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/** KXt8IMP_"y
* @return %vmd2}dA
* Returns the currentPage. Z=Y29V8
*/ <nk|Z'G E
publicint getCurrentPage(){ Nc+0_|,
return currentPage; >G`p T#
} %1#\LRA(
'{d_q6,%
/** ,3:f4e\<
* @param currentPage SdH=1zBc
* The currentPage to set. s$fM,l:!
*/ 1Yb &E7j
publicvoid setCurrentPage(int currentPage){ B!'K20"gF
this.currentPage = currentPage; IyO0~Vx>
} * F!B4go
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/** y [Vd*8
* @return +<E#_)}`D6
* Returns the everyPage. P'~`2W0sz
*/ >2#<gp3
publicint getEveryPage(){ er3Mvw
return everyPage; 6))":<J
} v`4w=!4
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/** %H\b5&
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* @param everyPage R0?bcP&
* The everyPage to set. uda++^y:
*/ Cd'D
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publicvoid setEveryPage(int everyPage){ _ZRmD\_t
this.everyPage = everyPage; kff N0(MR
} #S7oW@
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/** Fyvo;1a
* @return - (s0f
* Returns the hasNextPage. *f+s
*/ uEgR>X>
publicboolean getHasNextPage(){ Yn?beu'
return hasNextPage; 1Ek3^TOv7
} u7e$Mq
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/** 3,p!Fun:r
* @param hasNextPage Z
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* The hasNextPage to set. Fo3*PcUv
*/ *~8F.cx
publicvoid setHasNextPage(boolean hasNextPage){ ;f%@s1u
this.hasNextPage = hasNextPage; X;LYGJ{Xk
} =z}PR1X!
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/** O>)eir7
* @return 5AT^puL]]
* Returns the hasPrePage. s9C^Cy^su
*/ 0H_Ai=G
publicboolean getHasPrePage(){ qT?{}I
return hasPrePage; W* LC3B^
} t|@5,J
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/** &YIL As^8A
* @param hasPrePage M~zI;:0O
* The hasPrePage to set. O/eZ1YAC
*/ ?;tPqOs&
publicvoid setHasPrePage(boolean hasPrePage){ z$&B7?
this.hasPrePage = hasPrePage; |5flvkid
} >33=0<
_`gF%$]b
/** Mmz;
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* @return Returns the totalPage. mAlG}<
* K+Him]
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*/ yl$Ko
publicint getTotalPage(){ 1ZFKLI`V
return totalPage; !w7/G
} -aT-<+?s
inW7t2p<s
/** RZW=z}T+H
* @param totalPage J@>|`9T9$
* The totalPage to set. YI0l&'7
*/ :s_o'8z7L
publicvoid setTotalPage(int totalPage){ 7c_2.T@4
this.totalPage = totalPage; r 2:{r`ocM
} 8YZ9
10Eun }
} XU7to]'K
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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 r QzdHA
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个PageUtil,负责对Page对象进行构造: `GE8?UO-
java代码: [w}- )&c
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/*Created on 2005-4-14*/ ET^?>YsA
package org.flyware.util.page; u""26k51
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import org.apache.commons.logging.Log; Op0*tj2i),
import org.apache.commons.logging.LogFactory; Um/l{:S
xy`Y7W=
/** aUL7]'q}
* @author Joa 7s^b@&Le
* RV]#Bg*[#
*/ XrUI[ryE
publicclass PageUtil { #j7&2L
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privatestaticfinal Log logger = LogFactory.getLog QE/kR!r
/- Gq`9Z
(PageUtil.class); \asn^V@"zz
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/** M*k,M=sX
* Use the origin page to create a new page VMABj\yG
* @param page Uic
* @param totalRecords #i~P])%gNP
* @return HB#!Dv&'
*/ 7 Td
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publicstatic Page createPage(Page page, int S\ak(<X
tRPIvq/
totalRecords){ sm"Rp~[i
return createPage(page.getEveryPage(), 5~pxu
kmW/{I9,ua
page.getCurrentPage(), totalRecords); TgJ+:^+0
}
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-e$ T}3IV
/** Qz=e'H
* the basic page utils not including exception Lp%J:ogV`
;8=Bee4
handler C_3,|Zq?|
* @param everyPage 3` IR
^
* @param currentPage !hJ!ck]M
* @param totalRecords 7/M[T\c
* @return page /w?zO,!
*/ KHP/Y{mH
publicstatic Page createPage(int everyPage, int !L+b{
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currentPage, int totalRecords){ 2iKteJ@h)
everyPage = getEveryPage(everyPage); E6R\DM
currentPage = getCurrentPage(currentPage); MMO/vJC
int beginIndex = getBeginIndex(everyPage, WUauKRR.
%>/&&(BE
currentPage); xjD$i'V+
int totalPage = getTotalPage(everyPage, K:e[#b8:R
S*n5d >;
totalRecords); s Y4wdG
boolean hasNextPage = hasNextPage(currentPage, p%iZ6H>G
tVf):}<h
totalPage); Vk`Uz1*
boolean hasPrePage = hasPrePage(currentPage); 'uzHI@i
9e.v[K~
returnnew Page(hasPrePage, hasNextPage, 43g1/,klm
everyPage, totalPage, 9b6U]z,
currentPage, mph9/ %]S
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beginIndex); zk1]?
} ZUj1vf6I
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privatestaticint getEveryPage(int everyPage){ #'@@P6o5
return everyPage == 0 ? 10 : everyPage; -p0*R<t
} c0l?+:0M
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privatestaticint getCurrentPage(int currentPage){ 7}NvO"u
return currentPage == 0 ? 1 : currentPage; S@[NKY
} 8B+C[Q:+'
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privatestaticint getBeginIndex(int everyPage, int ts@w 9|
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Jn_
currentPage){ n4B
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return(currentPage - 1) * everyPage; ,Y|
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} G,+3(C
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privatestaticint getTotalPage(int everyPage, int -`\n/"#X6i
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totalRecords){ s(Wys^[g
int totalPage = 0; :3s^, g
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if(totalRecords % everyPage == 0) g`Q!5WK*
totalPage = totalRecords / everyPage; 89KFZ[.}]
else 3A0Qjj=
totalPage = totalRecords / everyPage + 1 ; =oq= ``%
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return totalPage; @K S .H
} [j
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privatestaticboolean hasPrePage(int currentPage){ KbciRRf!k
return currentPage == 1 ? false : true; ,c`Wmp^AY
} Gh6U<;V?*
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privatestaticboolean hasNextPage(int currentPage, }Q9+krrow
7wY0JS$fz
int totalPage){ rmC7!^/
return currentPage == totalPage || totalPage == }4piZ
ch
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0 ? false : true; "9X!Ewm"P
} vqVwo\oEdU
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} u^i3 @JuX
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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。 "1>w\21
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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 0k_3]Li=(
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做法如下: hpbi!g
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 6wbH{}\ll
4$mtc*tzT
的信息,和一个结果集List: LOG>x!
java代码: 8 .K; 2
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/*Created on 2005-6-13*/ ']sjW'~
package com.adt.bo; y,OG9iD:h
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import java.util.List; 6#qt%t%?D
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import org.flyware.util.page.Page; b5.]}>]t
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/** |+[Y_j
* @author Joa $*:$-
*/ w /PE )xA
publicclass Result { nW K7*
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private Page page; X f;R'a,$
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private List content; sk:B;.z
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/** O~?d;.b
* The default constructor %h,&N D
*/ (F3R!n
public Result(){ CGb4C(%-7
super(); c4Q9foE
} &sYxe:H
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/** }7xcHVO8-
* The constructor using fields <dVJV?i;
* Wl+spWqW
* @param page W1LR ,:$
* @param content 5G`fVsb
*/ R>5Xv%R
public Result(Page page, List content){ sX}#L
this.page = page; A>mk0P)~Q
this.content = content; 2AMb-&po&f
} QctzIC#;k
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/** n0EW
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* @return Returns the content. DSq?|H
*/ @,2,(=l*C
publicList getContent(){ *5hbD-a:
return content; J p^#G2
} }L%2K"8?}
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/** oIj-Y`92!
* @return Returns the page. E="uDHw+
*/ EDh-pK
public Page getPage(){ 9HPwl
return page; LCzeE7x
} %.'oY%
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/** je 3Qq1
* @param content tJ8:S@E3,
* The content to set. ,!PV0(F(
*/ B&1E&Cv_8
public void setContent(List content){ s%>8y\MaK
this.content = content;
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} q"S,<I<f
4M6[5RAW{
/** w-NTw2x,&
* @param page Tdz#,]Q
* The page to set. knpdECq&k
*/ 3J/l>1[
publicvoid setPage(Page page){ )iK:BL*Nw
this.page = page; cW"DDm
g
} jP2#w{xq
} hd(TKFL^y
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}s6Veosl
2|WM?V&
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2. 编写业务逻辑接口,并实现它(UserManager, >LH}A6dUC
3-1a+7fD
UserManagerImpl) .j>MsQP#\C
java代码: OA} r*Wz
23,pVo
J6>tGKa+e
/*Created on 2005-7-15*/ _% \%
package com.adt.service; 6-g>(g
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import net.sf.hibernate.HibernateException; /EegP@[
_Y}cK|3
import org.flyware.util.page.Page; 7&%HE\
#N~1Ye
import com.adt.bo.Result; \j BA4?(S
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1S
/** Q00v(6V46
* @author Joa :("@U,
*/ sX*L[3!vN
publicinterface UserManager { EwuRIe;D
/& c2y=/'C
public Result listUser(Page page)throws $<&_9T#&w
G%zJ4W%
HibernateException; UWK|_RT6SA
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} ]%FP*YU4O
@,c`#,F/
KK6z3"tk5
x(4"!#
V[WLS ?-)
java代码: %W=BdGr[8z
X=lsuKREZ
#sg
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/*Created on 2005-7-15*/ SXO.|"M
package com.adt.service.impl; I3'UrKKO
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import java.util.List; 2Qh)/=8lM
'$'a .q1q9
import net.sf.hibernate.HibernateException; ct
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""|;5kJS4
import org.flyware.util.page.Page; lFSvHs5
import org.flyware.util.page.PageUtil; 9vwm
RVN
[F;\NJp6?^
import com.adt.bo.Result; mE>{K
import com.adt.dao.UserDAO; E`hR(UL
?
import com.adt.exception.ObjectNotFoundException; euRKYGW
import com.adt.service.UserManager; GRVF/hPn
BSB&zp
/** qbCU&G|)
* @author Joa G`Z<a
*/ PlK3;
publicclass UserManagerImpl implements UserManager { 7zA+UWr
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private UserDAO userDAO; {.[EX MX
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/** ^;9l3P{
* @param userDAO The userDAO to set. =n_z `I
*/ mW+5I-~
publicvoid setUserDAO(UserDAO userDAO){ XzqB=iX
this.userDAO = userDAO; _8F;-7Sz
} KsK]y,^Z
;3xi.^=B
/* (non-Javadoc) sDTw</@
* @see com.adt.service.UserManager#listUser pzUr9
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(org.flyware.util.page.Page) *tk=D sRW
*/ .O(9\3q\
public Result listUser(Page page)throws 1LhZmv
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HibernateException, ObjectNotFoundException { C&%NO;Ole
int totalRecords = userDAO.getUserCount(); gyV`]uqG
if(totalRecords == 0) }bdoJ5
throw new ObjectNotFoundException 9V&+xbR&
[wiB1{/Ls.
("userNotExist"); UL#:!J/34
page = PageUtil.createPage(page, totalRecords); 2Oyw#1tdn
List users = userDAO.getUserByPage(page); ["Tro;K#
returnnew Result(page, users);
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} }u$c*}
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} MLM/!N 7
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)'e1@CR
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 m\/) m]wR
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询,接下来编写UserDAO的代码: j8bA"r1
3. UserDAO 和 UserDAOImpl: S~ S>62
java代码:
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m_Z(osoE#W
h&v].l
/*Created on 2005-7-15*/ 2_o\Wor#
package com.adt.dao; 9) $[W
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import java.util.List; <SOG?Lh~
,{msJyacmR
import org.flyware.util.page.Page; ycki0&n3
,`!lZ|
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import net.sf.hibernate.HibernateException; 02tN=}Cj)
-aE,KQ
/** F9r/
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* @author Joa F$|:'#KN
*/ ;mz#$"(
publicinterface UserDAO extends BaseDAO { F2_'U' a
#f_'&m
publicList getUserByName(String name)throws h6<i,1gQ1
y;4g>ma0
HibernateException; 3
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publicint getUserCount()throws HibernateException; +Zr~mwM=x
4KSq]S.
publicList getUserByPage(Page page)throws :[f[-F
+~of#
HibernateException; !+z^VcV
#Cy3x-!
} LjW32>B
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Vkd_&z7
KLVYWZib
java代码: x%goyXK
k $8Zg*)
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/*Created on 2005-7-15*/ @OUBo;/
package com.adt.dao.impl; JdUdl_Dz
TgDT
import java.util.List; Xo[cpcV
Q)M-f;O
import org.flyware.util.page.Page; E]g6|,4~-
^-n^IR}J
import net.sf.hibernate.HibernateException; (vzYgU,
import net.sf.hibernate.Query; ~&F|g2:
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import com.adt.dao.UserDAO; $F X$nY
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/** aK|
* @author Joa 5!$sQ@#}D
*/ +opym!\
public class UserDAOImpl extends BaseDAOHibernateImpl hJSWh5]
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implements UserDAO { VYh/URU>
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/* (non-Javadoc) XkoPN]0n
* @see com.adt.dao.UserDAO#getUserByName +t&)Z
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(java.lang.String) KHC Fz
*/ AW|SD
publicList getUserByName(String name)throws "iX\U'`
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HibernateException { fl9VokAT
String querySentence = "FROM user in class _?'W30Dg
)^4Ljb1
com.adt.po.User WHERE user.name=:name"; pr4y*!|Y$
Query query = getSession().createQuery v3t<rv
KU0Ad);e
(querySentence); q(hBqU W
query.setParameter("name", name); 9kqR-T|Q
return query.list(); fZsw+PSy
} vSoG] :1
N=T}
/* (non-Javadoc) )8}k.t>'s
* @see com.adt.dao.UserDAO#getUserCount() WJa7
*/ F:jtzy"
publicint getUserCount()throws HibernateException { wTZ(vX*mK
int count = 0; %Ny1H/@Q1+
String querySentence = "SELECT count(*) FROM H_x}-
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user in class com.adt.po.User"; |S@
Query query = getSession().createQuery #8M^;4N>[
Z(R0IW
(querySentence); _nxu8g]
count = ((Integer)query.iterate().next C0Fd<