Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 jj^{^,z\
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 J
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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 k,o|"9H
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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 e%#(:L
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分页支持类: @i`*i@g
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java代码: $Lpt2:.((
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package com.javaeye.common.util; o~7~S
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import java.util.List; jUjgxP*7m
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publicclass PaginationSupport { 2\h]*x%:
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publicfinalstaticint PAGESIZE = 30; S;DqM;Q
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privateint pageSize = PAGESIZE; kL;sA'I:S
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privateList items; *:r@-=M3=
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privateint totalCount; L{fKZ
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privateint[] indexes = newint[0]; t,$4J6
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privateint startIndex = 0; .nCF`5T!
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public PaginationSupport(List items, int J6Uo+0S
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totalCount){ nG<_&h
setPageSize(PAGESIZE); "&;>l<V
setTotalCount(totalCount); BS<5b*wG
setItems(items); \6A-eWIQif
setStartIndex(0); + v. I|c
} DiMkcK_e
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public PaginationSupport(List items, int _:oB#-0
}3sj{:z{
totalCount, int startIndex){ +4G]!tV6
setPageSize(PAGESIZE); 8[
setTotalCount(totalCount); 6t9Q,+nJ
setItems(items); %00KOM:
setStartIndex(startIndex); PveY8[i
} -r%4,4
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public PaginationSupport(List items, int A[QUFk(
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totalCount, int pageSize, int startIndex){ d?dZ=]~C
setPageSize(pageSize); UH=pQm^W
setTotalCount(totalCount); 9\9:)q
setItems(items); w"Gci~]bXU
setStartIndex(startIndex); ">='l9
} MY>mP
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publicList getItems(){ HGqT"NJr
return items; YTH3t]
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} \9Nd"E[B
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publicvoid setItems(List items){ ut8v&i1?
this.items = items; !{'C.sb?~
} E.V#Bk=
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publicint getPageSize(){ Db"jzMW.
return pageSize; vmW >$P
} yVQ0;h
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publicvoid setPageSize(int pageSize){ ? <b>2j
this.pageSize = pageSize; 1<y(8C6
} y[M<x5
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publicint getTotalCount(){ WGwpryaya
return totalCount; ;.$AhjqiP
} ;hP43Bi
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publicvoid setTotalCount(int totalCount){ Zpfsh2`
if(totalCount > 0){
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this.totalCount = totalCount; w1q-bIU
int count = totalCount / VJW%y)_[
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pageSize; D@9adwQb
if(totalCount % pageSize > 0) )+;Xfftz
count++; z ((Y \vP
indexes = newint[count]; ;S
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for(int i = 0; i < count; i++){ G 3))3]
indexes = pageSize * #{-l(016y
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} 1F`1(MYt9
}else{ a3t[Tk;
this.totalCount = 0; P)7:G?OTx
} \@")2o+
} )anprhc
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publicint[] getIndexes(){ 8YroEX[5l
return indexes; #-T xhwYs
} WdQR^'b$
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publicvoid setIndexes(int[] indexes){ }N@8zB~X
this.indexes = indexes; AlZ]UGf^
} %UGXgYDz
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publicint getStartIndex(){ ?T.'
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return startIndex; 3zC<k2B
} p'SclH[
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publicvoid setStartIndex(int startIndex){ ?@n,
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if(totalCount <= 0) =3K}]3f
this.startIndex = 0; ScN'|Ia.-
elseif(startIndex >= totalCount) {'O,G$Ldkr
this.startIndex = indexes lX g.`
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q<=j
[indexes.length - 1]; #)A.yK`u
elseif(startIndex < 0) .W;,~.l
this.startIndex = 0; e`]x?t<U4/
else{ k*xMe-
this.startIndex = indexes KK-}&N8
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[startIndex / pageSize]; <L!9as]w
} d@d\9*mn
} ~m`j=ot
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publicint getNextIndex(){ =r1-M.*a.M
int nextIndex = getStartIndex() + L_@P fI
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pageSize; '! \t!@I$
if(nextIndex >= totalCount) tk]>\}%
return getStartIndex();
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else x-E@[=
return nextIndex; 4$~A%JN3
} d8N{sT
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publicint getPreviousIndex(){ l~mC$>f
int previousIndex = getStartIndex() - eMHBY6<~=
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pageSize; Pp{Re|.
if(previousIndex < 0) KE$I!$zO
return0; _bsAF^ ;
else ~<Eu
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return previousIndex; t=(d, kf
} &9j*Y
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} uV=ZGr#o
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抽象业务类 }Od=WQv+
java代码: oy[>`qyz
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/** 5MX7V4ist
* Created on 2005-7-12 3*8m!gq7s
*/ xj<
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package com.javaeye.common.business; .DrGr:UW
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import java.io.Serializable; &x"hM
import java.util.List; zg}#X6\G<_
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import org.hibernate.Criteria; S UBrFsA
import org.hibernate.HibernateException; Z [Q jl*
import org.hibernate.Session; 3[*x'"Q;H
import org.hibernate.criterion.DetachedCriteria; %(}%#-X
import org.hibernate.criterion.Projections; &P pb2
import "=Xky,k
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org.springframework.orm.hibernate3.HibernateCallback; )x&4 Q=
import xofxE4.
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org.springframework.orm.hibernate3.support.HibernateDaoS HrK7qLw7
+~n"@ /
upport; [wkSY>Gu
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import com.javaeye.common.util.PaginationSupport; *KYh_i
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public abstract class AbstractManager extends )u?^w
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HibernateDaoSupport { c&"OhzzJK'
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privateboolean cacheQueries = false; M`D`-vv
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privateString queryCacheRegion; ,>3b|-C-
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publicvoid setCacheQueries(boolean XjFaP {
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cacheQueries){ w,zm$s ^
this.cacheQueries = cacheQueries; pY$DOr-r`
} 2J &J
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publicvoid setQueryCacheRegion(String pP)> x*1
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queryCacheRegion){ n2N:rP
this.queryCacheRegion = <Kk[^.7C;
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queryCacheRegion; &BOG&ot
} |'QgL0?
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publicvoid save(finalObject entity){ Hd ${I",
getHibernateTemplate().save(entity); 4<btWbk5u*
} tGwQUn
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publicvoid persist(finalObject entity){ h[& \OD,P
getHibernateTemplate().save(entity); cnL@j_mb
}
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publicvoid update(finalObject entity){ ekPn`U
getHibernateTemplate().update(entity); ,|^ lqY
} jRBKy8?[C
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publicvoid delete(finalObject entity){ )YPut.
getHibernateTemplate().delete(entity); jmr1e).];
} 4"et4Y7
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publicObject load(finalClass entity, RD6`b_]o
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finalSerializable id){ |IZFWZd
return getHibernateTemplate().load {s3 j}&
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(entity, id); C<E;f]d
} 55V&[>|K5
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publicObject get(finalClass entity, .B_a3K4'{^
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finalSerializable id){ (i@B+c
return getHibernateTemplate().get ?UBhM,;XK
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(entity, id); +"3K)9H
} %Hpz^<`
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publicList findAll(finalClass entity){ m%.7l8vT
return getHibernateTemplate().find("from UEH+E&BCC
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" + entity.getName()); %0lJ(hm
} yL"pzD`[H
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publicList findByNamedQuery(finalString ,K8(D<{
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namedQuery){ V~4yS4
return getHibernateTemplate *GC9o/
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().findByNamedQuery(namedQuery); ^ Iy'<J
} p77
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publicList findByNamedQuery(finalString query, Ji;R{tZ.R
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finalObject parameter){ P3+?gW'
return getHibernateTemplate ,7^,\ ,-m
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().findByNamedQuery(query, parameter); TU O*w
} ]oE:p
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publicList findByNamedQuery(finalString query, :=2l1Y[-G
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finalObject[] parameters){ `t Zw(Z=h
return getHibernateTemplate }Oe9Zq
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().findByNamedQuery(query, parameters); ^<v]x;
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} gB}UzEj^<
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publicList find(finalString query){ }NF7"tOL
return getHibernateTemplate().find #RVN7-x
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(query); .Eg[[K_iD
} "V:E BR
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publicList find(finalString query, finalObject =(]||1.
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parameter){ Jsw%.<
return getHibernateTemplate().find Bw*6X`'Q
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(query, parameter); 5 $:
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} Z >F5rkJ
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public PaginationSupport findPageByCriteria =J827c{.
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(final DetachedCriteria detachedCriteria){ <"}WpT
return findPageByCriteria >
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); %#-'|~
} 6),VN>j
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public PaginationSupport findPageByCriteria X.hVMX2B
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(final DetachedCriteria detachedCriteria, finalint mFeoeI,Jv
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startIndex){ #hP&;HZ2>"
return findPageByCriteria _%6Vcy
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(detachedCriteria, PaginationSupport.PAGESIZE, @DK;i_i
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startIndex);
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} "%fvA;
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public PaginationSupport findPageByCriteria ui4*vjd
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(final DetachedCriteria detachedCriteria, finalint E|5lm
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pageSize, (Gpk;DD
finalint startIndex){ t9+ME|
return(PaginationSupport) rhvTV(Bz
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getHibernateTemplate().execute(new HibernateCallback(){ 4&/m>%r
publicObject doInHibernate nk-V{']
)1 =|\
(Session session)throws HibernateException { #vBS7ba
Criteria criteria = UJ1Ecob
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detachedCriteria.getExecutableCriteria(session); q+}Er*r
int totalCount = 7(1UXtT
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((Integer) criteria.setProjection(Projections.rowCount U8s&5~IPn
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()).uniqueResult()).intValue(); HE>sZ;
criteria.setProjection #+6t|
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(null); { 0vHgi
List items = eE-c40Bae
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criteria.setFirstResult(startIndex).setMaxResults 1pHt3Vc(G
>5+]~[S
(pageSize).list(); &0QtHcXpR
PaginationSupport ps = ^VAvQ(b!:i
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new PaginationSupport(items, totalCount, pageSize, "8YXFg
]eD5It\
startIndex); ;yVT:qd
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return ps; Ij}k>qO/2
} +/Q?<*[
}, true); f]JLFg7
} !
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public List findAllByCriteria(final PDH00(#;+
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DetachedCriteria detachedCriteria){
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return(List) getHibernateTemplate p.J+~s4G
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().execute(new HibernateCallback(){ Z2wgfP`
publicObject doInHibernate A-XWG9nL
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(Session session)throws HibernateException { X`E3lgfqT
Criteria criteria = 8!q$8]M
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detachedCriteria.getExecutableCriteria(session); Lp}>WCams
return criteria.list(); &*r'Sx)V
} b&~s}IX
}, true); M,j3 z#
} h,WF'X+
sHi *\
public int getCountByCriteria(final %.3]F2_Q
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DetachedCriteria detachedCriteria){ 98^o9i
Integer count = (Integer) %.+#e
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getHibernateTemplate().execute(new HibernateCallback(){ W u9))Ir
publicObject doInHibernate 3Az7urIY
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(Session session)throws HibernateException { _Bhm\|t
Criteria criteria = qe\JO'g#e
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detachedCriteria.getExecutableCriteria(session); @p}"B9h*^
return [~_()i=Y
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criteria.setProjection(Projections.rowCount +bv-! rf
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()).uniqueResult(); 2UGnRZ8:1Y
} -g;cg7O#(
}, true); KqH_?r`
return count.intValue(); a1nj}1M%
} S66..sa
} {~RS$ |
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用户在web层构造查询条件detachedCriteria,和可选的 I/
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 OKH4n/pq
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PaginationSupport的实例ps。 ao(lj
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ps.getItems()得到已分页好的结果集 3?rYt:Uf!
ps.getIndexes()得到分页索引的数组 8w|-7$ v
ps.getTotalCount()得到总结果数 8^FAeV#
ps.getStartIndex()当前分页索引 F3L'f2yBG
ps.getNextIndex()下一页索引 o :tz_5
ps.getPreviousIndex()上一页索引 Xob,jo}a
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 _Ka6! 9
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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 v>&sb3I
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一下代码重构了。 AM ZWPU
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我把原本我的做法也提供出来供大家讨论吧: J"&jR7-9
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首先,为了实现分页查询,我封装了一个Page类: 7Ib/Cm0d|
java代码: }}g.L|
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/*Created on 2005-4-14*/ Y,%d_yR[
package org.flyware.util.page; -!kfwJg8N(
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/** v_$'!i$
* @author Joa Gc'CS_L
* lW!}OzE(m
*/ 0Ek+ }`
publicclass Page { /s\_"p
+?!x;qS^
/** imply if the page has previous page */ m<DiYxK
privateboolean hasPrePage; W_ =
SX4"HadV>
/** imply if the page has next page */ %bp8VR sY
privateboolean hasNextPage; }95;qyQ$
5:o$]LkOWC
/** the number of every page */ d? Old
privateint everyPage; lhk[U!>#
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/** the total page number */ p? dXs^ c
privateint totalPage; *+-L`b{SX
TC=djC4$/
/** the number of current page */ ,bQbj7
privateint currentPage; qXH\e|
@vC7j>*4B
/** the begin index of the records by the current 45u\v2,C3
Y)-)owx7
query */ .[1"3!T
privateint beginIndex; u9:+^F+
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/** The default constructor */ @"\j]ZEnY
public Page(){ `Z}7G@ol
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} )<kId4E
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/** construct the page by everyPage *f? z$46
* @param everyPage 4|Wglri
* */
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public Page(int everyPage){ ~is$Onf99#
this.everyPage = everyPage; epWO}@
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} x*EzX4$x
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/** The whole constructor */ Z]1=nSv
public Page(boolean hasPrePage, boolean hasNextPage, eu]t.Co[X
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int everyPage, int totalPage, !F|mCEU
int currentPage, int beginIndex){ (&w'"-`
this.hasPrePage = hasPrePage; lYS+EVcR
this.hasNextPage = hasNextPage; me#?1r
this.everyPage = everyPage; $ON4nx
this.totalPage = totalPage; abHW[VP9
this.currentPage = currentPage; Vu%XoI)<KY
this.beginIndex = beginIndex; vBMuV pzO
} Xy74D/ocui
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/** j A 9!
* @return |HjoaN )
* Returns the beginIndex. `ehZ(H}
*/ -7^A_!.
publicint getBeginIndex(){ :%!}%fkxH
return beginIndex; M<A*{@4$w&
} _::q
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/** 1|?8g2Vf
* @param beginIndex h "7:&=e
* The beginIndex to set. PJ=N.xf}
*/ N(%%bHi#V
publicvoid setBeginIndex(int beginIndex){ ii.L]#3y
this.beginIndex = beginIndex; DA/l`Pn
} {M7`z,,[
J H%^FF2
/** [|=#~(yYQ
* @return ,s%1#cbR
* Returns the currentPage. e~#"#?
*/ pT90TcI2
publicint getCurrentPage(){ xm)s%"6n
return currentPage; 1N`1~y
} Br}&
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/** ~\4B 1n7
* @param currentPage aKLA_-E
* The currentPage to set. dFd^@b
*/ ad\?@>[I
publicvoid setCurrentPage(int currentPage){ 2 kOFyD
this.currentPage = currentPage; -:hiLZJ7-
} <K~> :4c
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/** 9@Iz:!oqb
* @return '`-W!g[
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* Returns the everyPage. AhZ`hj
*/ h6*&1r
publicint getEveryPage(){ `A]CdgA
return everyPage; %uuh+@/&yz
} )JO#Z(
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/** Kk}|[\fW
* @param everyPage AoaRlk-#
* The everyPage to set. J3]!<v=
*/ V~Zi #o
publicvoid setEveryPage(int everyPage){ qk;vn}auD]
this.everyPage = everyPage; FS3MR9
} W\'njN
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/** DcNQ2Zz?%
* @return %idn7STJ}
* Returns the hasNextPage. 1]yOC)u"i
*/ >-2eZ(n)"
publicboolean getHasNextPage(){ [79 eq=
return hasNextPage; (,5oqU9s@
} O'6zV"<P
=!axQ[)A
/** thoAEG80
* @param hasNextPage ")/TbTVu
* The hasNextPage to set. hX-([o
*/ vv2N;/;I
publicvoid setHasNextPage(boolean hasNextPage){ y_^w|
this.hasNextPage = hasNextPage; _RLx;Tn)L
} HF9\SVR
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/** KGMX >t'
* @return `y&d
* Returns the hasPrePage. ]=s!cfu
*/ o/EN3J
publicboolean getHasPrePage(){ GM.2bA(y
return hasPrePage;
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} s6#@S4^=\
ZS&n,<a5L}
/**
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* @param hasPrePage dXkgWLI~
* The hasPrePage to set. +N161vo7
*/ ?[$=5?
publicvoid setHasPrePage(boolean hasPrePage){ BrW1:2w
>\
this.hasPrePage = hasPrePage; ;2o+|U@
} pK)*{fC$`
p^2"g~
/** i\P?Y(-{
* @return Returns the totalPage. - nWs@\
* :NB,Dz+i
*/ }E01B_T9z
publicint getTotalPage(){ XA
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return totalPage; ep"YGx[V
} 64Ot`=A"
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/** h)%}O.ueB
* @param totalPage 87/!u]q
* The totalPage to set. 9n$0OH
/q
*/ pNOVyyo>BW
publicvoid setTotalPage(int totalPage){ -{Lc?=
this.totalPage = totalPage; F1V[8I.0
} ?)B"\#`t
+]n.uA-`[a
} I91pX<NBf
; Nw.
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-IBf;"8f
Sm(QgZO[4
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 9Fe(],AzF
ryz
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个PageUtil,负责对Page对象进行构造: #z|\AmZ\
java代码: ~[@Gj{6p0
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^
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/*Created on 2005-4-14*/ ];bl;BP
package org.flyware.util.page; Z[.+Wd\)-9
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import org.apache.commons.logging.Log; d^"dL" Q6m
import org.apache.commons.logging.LogFactory; #!IezvWf
o<`)cb }
/** Sz\"*W;>
* @author Joa ^wL
n
* )4d)G5{
*/ t6.hg3Y
publicclass PageUtil { m){.{Vn]
\bt+46y@]
privatestaticfinal Log logger = LogFactory.getLog x+V;UD=mH
a:C'N4K
(PageUtil.class); >*xa\ve
}*!7
Vrep
/** Tct[0B
* Use the origin page to create a new page ^ <Z^3c>/
* @param page ,`7;S,f
* @param totalRecords `aFy2x`3
* @return <1(:W[M
*/ j @c
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publicstatic Page createPage(Page page, int 4X2XSK4
1Aq*|JSk(
totalRecords){ stnyJ9
return createPage(page.getEveryPage(), r7tN(2;5
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page.getCurrentPage(), totalRecords); ;H#'9p ,2
} lFWN[`H
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/** q% Eze
* the basic page utils not including exception |Rr^K5hmD
&a?&G'?
handler &"dT/5}6
* @param everyPage LGN,8v<W(
* @param currentPage mU1lEx$
* @param totalRecords 1sFTXl
* @return page WA-`
*m$v
*/ m`<Mzk.u<
publicstatic Page createPage(int everyPage, int RUTlwTdv
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currentPage, int totalRecords){ 2[&3$-]
everyPage = getEveryPage(everyPage); Jji~MiMn
currentPage = getCurrentPage(currentPage); 0\tk/<w2
int beginIndex = getBeginIndex(everyPage, X !5
7s%DM6li 6
currentPage); C24[brf
int totalPage = getTotalPage(everyPage, gY AXUM,
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totalRecords); /^~3Ib8Fw+
boolean hasNextPage = hasNextPage(currentPage, lAsDdxB`
+w Oa
totalPage); ,jWMJ0X/N=
boolean hasPrePage = hasPrePage(currentPage); t&UPU&tY
/#Y)nyE
returnnew Page(hasPrePage, hasNextPage, M.K-)r,
everyPage, totalPage, 73/kyu-0%
currentPage, Q)\7(n
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beginIndex); $'3`$
} +zxj-diM
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privatestaticint getEveryPage(int everyPage){ xq:.|{HUk
return everyPage == 0 ? 10 : everyPage; <dx
xXzLT
} _//)|.6c3
bWv4'Y!p
privatestaticint getCurrentPage(int currentPage){ -If-c'"G
return currentPage == 0 ? 1 : currentPage; `fEB,0j^
} &x{CC@g/
nu,#y"WQ
privatestaticint getBeginIndex(int everyPage, int ./@!k[
#n^P[Zw
currentPage){ -bHQy:
return(currentPage - 1) * everyPage; YmM+x=G:
} VOBzB]
:ho)3kB
privatestaticint getTotalPage(int everyPage, int @sly-2{e1
RQI? \?o
totalRecords){ !|`G<WD
int totalPage = 0; ]trVlmZXH}
ReOp,A/y
if(totalRecords % everyPage == 0) 2=X 2M
totalPage = totalRecords / everyPage; -ea>}S
else -SaH_Nuj
totalPage = totalRecords / everyPage + 1 ; =whZ?,u1
0uzm@'^
return totalPage; Ec| Gom?
} O=}4?Xv
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privatestaticboolean hasPrePage(int currentPage){ b:.aZ7+4
return currentPage == 1 ? false : true; BP2-LG&\
} <va3L y)c&
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privatestaticboolean hasNextPage(int currentPage, v8"plx=3
\P]w^
int totalPage){ Ev;HV}G
return currentPage == totalPage || totalPage == M:|Z3p K
H8~<;6W
0 ? false : true; J#B%
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} TEl:;4
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} `_sc_Y|C!
pN/)$6=
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&~U!X~PpB
!%x8!;za
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 ) W)m?%
UKp- *YukT
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 > 4ex:Z
6>v`6
做法如下: Vu '/o[nF>
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 pv&:N,p
3o%,8l,
的信息,和一个结果集List: YQOdwcLG
java代码: 9;s:Bo
v5l)T}Nb
^'i(@{{o\
/*Created on 2005-6-13*/ `;b@a<Wl
package com.adt.bo; {4Y@DQ-
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import java.util.List; Tx?,]c,(u
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import org.flyware.util.page.Page; T6JN@:8
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/** Zws[}G"7h
* @author Joa Z`nHpmNM
*/ R%o:'-~
publicclass Result { ;4tVFqR
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private Page page; %o9@[o
.]
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private List content; L<!}!v5ja
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/** Xn-GSW3{
* The default constructor \y^ Od7F
*/ F+Rtoq|
public Result(){ 8*3o9$Pj
super(); pDb5t>
} 'Ca6cm3Tg
\bqIe}3V7
/** PHl{pE*
* The constructor using fields m8eyAvi6
* %"PG/avo
* @param page s42M[BW]
* @param content .GUm3b
*/ D'Tb=
public Result(Page page, List content){ $9<q'hf<w
this.page = page;
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this.content = content; l CHaRR7
} 90> (`pI=
`rsPIOu
/** K[0.4+
* @return Returns the content. 5G=<2;
*/ 8A}w}h
publicList getContent(){ % eWzr
return content; ia
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} !!Z#'Wq
4s nL((
/** =LV7K8FSd
* @return Returns the page. tAFKq>\
*/ 3Yf&F([t
public Page getPage(){ w2!G"oD
return page; n4Nb,)M
} SLp &_S@4
01N"
/** w naP? |/
* @param content {'VP_ZS1v
* The content to set. r(xh5{^x
*/ O6Bs!0,
public void setContent(List content){ t-Rfy`I3
this.content = content; D7|[:``
} (n+2z"/
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/** RY'f%c
* @param page :;W[@DeO[
* The page to set. O*{<{3
*/ Pe6}y
publicvoid setPage(Page page){ "*W:
this.page = page; 2^w3xL"
} r!SMF]?SJ
} ^Gt&c_gH
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RUqN,C,m5I
i'9aQi"G
XWN
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2. 编写业务逻辑接口,并实现它(UserManager, <WFA3
G n"]<8yl~
UserManagerImpl) |N_tVE
java代码: m3W:\LTTp
>QO^h<.>
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/*Created on 2005-7-15*/ Fw5|_@&k
package com.adt.service; _+PiaJ&'
/a.4atb0
import net.sf.hibernate.HibernateException; ?q a
't:$Lx
import org.flyware.util.page.Page; F: %-x=q
l?pF?({
import com.adt.bo.Result; NRu_6~^^
i
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/** eKjmU | H
* @author Joa ~!UC:&UKo
*/ Yt&Isi
+
publicinterface UserManager { hhd%j6
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public Result listUser(Page page)throws ;6S,|rC]
XN9s!5A<L)
HibernateException; V/|).YG2
:T^!<W4
} wK OljE6d
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uQh dg4
X[/>{rK
0VsQ$4'V^
java代码: 4x7(50hp#
6.
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"fK`F/
/*Created on 2005-7-15*/ *69{#qN
package com.adt.service.impl; -e<d//>
e RY2.!
import java.util.List; Fp'qn'){:#
^X-3YhJ4U
import net.sf.hibernate.HibernateException; <xpOi&l
R_9 &V!fl
import org.flyware.util.page.Page; \kSoDY`l&
import org.flyware.util.page.PageUtil; Zoe>Ow8mE`
LXYpP-E
import com.adt.bo.Result; :})(@.H
import com.adt.dao.UserDAO; yg({g
"
import com.adt.exception.ObjectNotFoundException; m$<LO%<~p
import com.adt.service.UserManager; p3tu_If
h OYm
=r
/** 9R_2>BDn
* @author Joa k1tJ$}
*/ X&C&DTB
publicclass UserManagerImpl implements UserManager { j("$qpv
vJZ0G:1
private UserDAO userDAO; 8vQGpIa,
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/** >,c$e' h
* @param userDAO The userDAO to set. 8VG6~>ux'>
*/ ^n8ioL\*i
publicvoid setUserDAO(UserDAO userDAO){ AI
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this.userDAO = userDAO; &\<!{Y<'
} MJ5Ymt a
FY;\1bt<<
/* (non-Javadoc) MTBHFjXO
* @see com.adt.service.UserManager#listUser 7AwV4r*:
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(org.flyware.util.page.Page) F`!B!uY
*/ J|*Z*m
public Result listUser(Page page)throws -s~6FrKy
y?=W
HibernateException, ObjectNotFoundException { $ti*I;)h4
int totalRecords = userDAO.getUserCount(); U'(Exr[
if(totalRecords == 0) b-*3]gB
throw new ObjectNotFoundException 6P,vGmR
]U[y3
("userNotExist"); Pjz_KO/
page = PageUtil.createPage(page, totalRecords); a=ye!CN^
List users = userDAO.getUserByPage(page); EQQ/E!N8l
returnnew Result(page, users); b"D? @dGB,
} tG8)!
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} ed3d 6/%HR
~ZrSoVP=
LV4\zd6
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其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 b1+6I_u.
H~Z$ pk%
询,接下来编写UserDAO的代码: qY,z,oAF
3. UserDAO 和 UserDAOImpl: b\6)whh
java代码: . <xzf4C
&[u>^VO8
:LE0_ .
/*Created on 2005-7-15*/ lKVy{X3]*
package com.adt.dao; j@chSk"K
R%gkRx[
import java.util.List; :TU|;(p
ku2gFO
import org.flyware.util.page.Page; s|40v@M
|W't-}yf
import net.sf.hibernate.HibernateException; }iGpuoXT`
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/** R$>]7-N}
* @author Joa @ P:b\WCI
*/ IE;Fu67wi
publicinterface UserDAO extends BaseDAO { ]JGh[B1gh
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publicList getUserByName(String name)throws L >*
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HibernateException; 9gu$vF]9!
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publicint getUserCount()throws HibernateException; !v/j*'L<M}
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publicList getUserByPage(Page page)throws 0 QzUcr)3+
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HibernateException; iJ8 5okv'
tKr.{#)
} .`I;qF
\o|5/N
1yFVF
L#
yQP!Vt^
java代码: aJ!(c}N~97
+jpaBr-O#
$x5,Oe n
/*Created on 2005-7-15*/ b*;zdGX.A9
package com.adt.dao.impl; N3M:|D
N+)gYb6h
import java.util.List; ]YQ!i@Y
W|~Jl7hs8Q
import org.flyware.util.page.Page; !@6P>HzY$
d3nx"=Cy0I
import net.sf.hibernate.HibernateException; t=-t xnlr<
import net.sf.hibernate.Query; nqp:nw
D)kh"cK*1
import com.adt.dao.UserDAO; YwbRzY-#F
d]3c44kkK{
/** Yg @&@S]
* @author Joa 6}V)\"u&
*/ 4=;.<
public class UserDAOImpl extends BaseDAOHibernateImpl 4jWzYuI&J
s=[Tm}[
implements UserDAO { {|R@\G.1(
Sio> QL Y
/* (non-Javadoc) ,^Cl?\9"
* @see com.adt.dao.UserDAO#getUserByName +2DzX/3
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(java.lang.String) !b !C+ \v
*/ qcNu9Ih
publicList getUserByName(String name)throws Ou26QoT9XI
%NyV2W=~X
HibernateException { 3CKd[=-Z
String querySentence = "FROM user in class @Feusprs
I "8:IF
com.adt.po.User WHERE user.name=:name"; b 8vyJb,K
Query query = getSession().createQuery -d j9(~?^
<>|&%gmz
(querySentence); DGs=.U-=e
query.setParameter("name", name); {S9't;%]
return query.list(); +%O_xqq
} P^lzl:|
/mi9q
/* (non-Javadoc) \2UtT@3|C
* @see com.adt.dao.UserDAO#getUserCount() SxX2+|0g`g
*/ S.: m$s
publicint getUserCount()throws HibernateException { U@;W^Mt
int count = 0; gY\g+df-
String querySentence = "SELECT count(*) FROM yN'<iTh
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user in class com.adt.po.User"; ZWtlO P#]
Query query = getSession().createQuery /w!!jj^
8fG$><@
(querySentence); |UudP?E
count = ((Integer)query.iterate().next $0kuR!U.N
qdM=}lbc
()).intValue(); gs xT
return count; Q3@MRR^tY
} k$ya.b<X/
}3b3^f
/* (non-Javadoc) b I%Sq+"}
* @see com.adt.dao.UserDAO#getUserByPage pBZf=!+E
2qA"emUM
(org.flyware.util.page.Page) +t9$*i9`L
*/ B%]yLJ
publicList getUserByPage(Page page)throws A:-M RhE9X
nnzfKn:J
HibernateException { jfLkp>2E'
String querySentence = "FROM user in class |D@/4B1P
fZq_]1(/uP
com.adt.po.User"; \Zn%r&(
Query query = getSession().createQuery "k;j@
)}Vb+
(querySentence); Bql5=p
query.setFirstResult(page.getBeginIndex()) ]j4Nl?5*x
.setMaxResults(page.getEveryPage()); GlVb |O"
return query.list(); &N