Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 UbY-)9==
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 uZm<:d2%)
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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 dfc-#I
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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 Lkqu"V
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分页支持类: xx!o]D-}
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java代码: ;`X -.45
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package com.javaeye.common.util; @_1$
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import java.util.List; I4qzdD
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publicclass PaginationSupport { )c]GgPH
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publicfinalstaticint PAGESIZE = 30; 1MfRFv
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privateint pageSize = PAGESIZE; EJdq"6S
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privateList items; *7BY$q
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privateint totalCount; 2ZIf@C{P.
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privateint[] indexes = newint[0]; 8Nc i1o
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privateint startIndex = 0; qL A
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public PaginationSupport(List items, int () b0Sh=
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totalCount){ !Q cgTW)T
setPageSize(PAGESIZE); lSXhHy
setTotalCount(totalCount); }! zjj\g^
setItems(items); <(3Uu()
setStartIndex(0); OEdp:dW|
} LEyn1d
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public PaginationSupport(List items, int "9kEqz4a
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totalCount, int startIndex){ ;PG'em
setPageSize(PAGESIZE); clG3t
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setTotalCount(totalCount); 4sNM#]%|
setItems(items); 4J94iI>S.l
setStartIndex(startIndex); jDH)S{k
} I`Rxijz
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public PaginationSupport(List items, int u`E_Q8
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totalCount, int pageSize, int startIndex){ O=c&
setPageSize(pageSize); nfRo:@
setTotalCount(totalCount); D!qtb6<.
setItems(items); YJrK oK}
setStartIndex(startIndex); 8'`&f&
} Vk0O^o
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publicList getItems(){ O!Mm~@MoA
return items; #z~D1Zl
} >a_K:O|AJ
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publicvoid setItems(List items){ ?G!^|^S*
this.items = items; nez5z:7F
} g.F{yX]
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publicint getPageSize(){ +/x|P-
return pageSize; ~X`vRSrH
} f4!^0%l
#'$CC<*vy
publicvoid setPageSize(int pageSize){ Pvbw>k;
this.pageSize = pageSize; RoJ&dK
} ;#rtV;
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publicint getTotalCount(){ U?xl%qF`)
return totalCount; G>#L
} kE6\G}zj
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publicvoid setTotalCount(int totalCount){ ^9cqT2:t
if(totalCount > 0){ {Z-5
this.totalCount = totalCount; M7jDV|Go
int count = totalCount / IO v4Zx<)
p)TH^87
pageSize; 'y'>0'et
if(totalCount % pageSize > 0) Eptsxyz{
count++; Kq-y1h]7H
indexes = newint[count]; aASnk2DFd
for(int i = 0; i < count; i++){ pC#Z]_k
indexes = pageSize * LNg[fF^:
} c&Zv#iO6
i; $5il]D`
} x%cKTpDh!
}else{ #H7(d T
this.totalCount = 0; l9P~,Ec4''
} ukG1<j7.
} 1AoBsEnd
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publicint[] getIndexes(){ M}38uxP
return indexes; ^@{'! N
} ^0X86
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publicvoid setIndexes(int[] indexes){ j
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this.indexes = indexes; E.6^~'/
} {
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publicint getStartIndex(){ d*q_DV
return startIndex; li/O&@g`
} `@Kh>K
{/#?n["
publicvoid setStartIndex(int startIndex){ atl0#F Bd
if(totalCount <= 0) &yVii^
this.startIndex = 0; ;'=!Fv
elseif(startIndex >= totalCount) K})j5CJ/
this.startIndex = indexes {yspNyOx
/\#qz.c2K
[indexes.length - 1]; N;Hf7K
elseif(startIndex < 0) 1*>a
this.startIndex = 0; S1`+r0Fk~n
else{ 0 B3*\ H}5
this.startIndex = indexes $9Z8P_^.0(
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[startIndex / pageSize]; eZP"M6
} EkXns%][L
} AQ+w%>G6
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publicint getNextIndex(){ 3fM
int nextIndex = getStartIndex() + HC!$Z`}Y
'<1T>|`/t
pageSize; >@ge[MuS
if(nextIndex >= totalCount) 1j0yON
return getStartIndex(); =>S5}6
else +TUtVG
return nextIndex; !^`ZHJ-3>;
} /*D]4AK
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publicint getPreviousIndex(){ !f7}5/YC7v
int previousIndex = getStartIndex() - 7/aJ?:gX
q;B-np?U
pageSize; '1.T-.4>&
if(previousIndex < 0) {u9VHAXCf
return0; V3I&0P k
else O a-ZeCq
return previousIndex; 9"MC<
} yt_?4Hc"
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} {I(Euk>lR
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:/Sx\Nz78
抽象业务类 )(75dUl
java代码: 7b'XQ/rs
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/** ]
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* Created on 2005-7-12 hnG'L*HooE
*/ Z;??j+`Eo
package com.javaeye.common.business; :LcR<>LZ
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import java.io.Serializable; $?;aW^E
import java.util.List; OZk(VMuI
8$3 Tu"+;
import org.hibernate.Criteria; ^pZ(^
import org.hibernate.HibernateException; C/
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import org.hibernate.Session; wl5!f|
import org.hibernate.criterion.DetachedCriteria; t^u X9yvx
import org.hibernate.criterion.Projections; 7,Z%rqf\)
import G}f.fRY
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org.springframework.orm.hibernate3.HibernateCallback; #^Sd r-
import :ykQ[d`:|
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org.springframework.orm.hibernate3.support.HibernateDaoS r 97 VX>
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upport; ~} wPiu,
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import com.javaeye.common.util.PaginationSupport; T7!a@
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public abstract class AbstractManager extends 46}/C5
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HibernateDaoSupport { }bix+/]
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privateboolean cacheQueries = false; HOu<,9?>Q
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privateString queryCacheRegion; yrkd#m
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publicvoid setCacheQueries(boolean e2/&X;2
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cacheQueries){ [/5>)HK} C
this.cacheQueries = cacheQueries; `iQyKZS/+
} dsJ}C|N
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publicvoid setQueryCacheRegion(String #2x\d
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queryCacheRegion){ $K;4=zN>t:
this.queryCacheRegion = P1z6sGG
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queryCacheRegion; u%h]k ,(E
} p?8>9
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publicvoid save(finalObject entity){ AO/J:`
getHibernateTemplate().save(entity); i3#]_ p{
} yUNl)E
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publicvoid persist(finalObject entity){ Ct
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getHibernateTemplate().save(entity); #T
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} |{ *ce<ip5
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publicvoid update(finalObject entity){ 0jj
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getHibernateTemplate().update(entity); Hhfqb"2on
} 80:na7$)#
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publicvoid delete(finalObject entity){ 5#WZXhlc}
getHibernateTemplate().delete(entity); =EV8~hMyqh
} I9tdr<
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publicObject load(finalClass entity, L`];i8=I
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finalSerializable id){ NIV&)`w
return getHibernateTemplate().load -FE5sW
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(entity, id); Ur5X~a\y
} J,P7k$t2vv
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publicObject get(finalClass entity, :/
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finalSerializable id){ bpKb<c
return getHibernateTemplate().get GAz;4pUZ
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(entity, id); F>!fu.Ws
} zb:p,T@5
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publicList findAll(finalClass entity){ ~-'nEA TE
return getHibernateTemplate().find("from aD%")eP%&
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" + entity.getName()); C]eb=rw$
} P#76ehR]K
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publicList findByNamedQuery(finalString #gi&pR'$
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namedQuery){ =]etw
return getHibernateTemplate J#'c+\B<2X
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().findByNamedQuery(namedQuery); ii{5z;I]X
} ,X9Y/S
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publicList findByNamedQuery(finalString query, LTFA2X&E=
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finalObject parameter){ L88oh&M
return getHibernateTemplate lD 9'^J
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().findByNamedQuery(query, parameter); DQ~+\
} H-0deJ[>
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publicList findByNamedQuery(finalString query, vW YN?"d
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finalObject[] parameters){ +F4xCz7f
return getHibernateTemplate d]w*fn
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().findByNamedQuery(query, parameters); [.|tD
} a-8~f8na{(
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publicList find(finalString query){ /:C"n|P7Z
return getHibernateTemplate().find 7F.>M
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(query); NeeymyW
} sF(U?)48
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publicList find(finalString query, finalObject $6ITa }o
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parameter){ (3=. 3[
return getHibernateTemplate().find [wIyW/+
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(query, parameter); NoiU5pP
} 1~ZDHfd5
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public PaginationSupport findPageByCriteria Q_M2!qj
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(final DetachedCriteria detachedCriteria){ =:9n+7~$
return findPageByCriteria cUS2*7h
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); evtn/.kDR
}
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public PaginationSupport findPageByCriteria S.M< (
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(final DetachedCriteria detachedCriteria, finalint +ZGOv,l
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startIndex){ sHh2>f@x$
return findPageByCriteria )e]:T4*vo
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(detachedCriteria, PaginationSupport.PAGESIZE, ]Jv Z:'g}
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startIndex); 7.akp
} )M^;6S
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public PaginationSupport findPageByCriteria M`iJ6L
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(final DetachedCriteria detachedCriteria, finalint 9 Q].cDe[
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pageSize, LOe!qt\&
finalint startIndex){ 4Mg09
return(PaginationSupport) ZYu^Q6b3
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getHibernateTemplate().execute(new HibernateCallback(){ zB 7wGl9
publicObject doInHibernate bCA3w%,kM
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(Session session)throws HibernateException { )mwY]
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Criteria criteria = nef-xxXC^I
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detachedCriteria.getExecutableCriteria(session); 7|65;jm+
int totalCount = lm-ubzJN
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((Integer) criteria.setProjection(Projections.rowCount _BcB@a
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()).uniqueResult()).intValue(); z,/dYvT<
criteria.setProjection ChGwG.-%L
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(null); Gs*ea'T)
List items = }L:LcM
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criteria.setFirstResult(startIndex).setMaxResults LhV4 ^\+
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(pageSize).list(); /A##Yv!biR
PaginationSupport ps = `qs'={YtU
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new PaginationSupport(items, totalCount, pageSize, ;|9VPv/
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startIndex); lywcT! <
return ps; 1\zI#"b ^
} Zj`eR\7~
}, true); TX;OA"3=\-
} %'^m6^g;
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public List findAllByCriteria(final )@))3
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DetachedCriteria detachedCriteria){ Bg7?1m
return(List) getHibernateTemplate F"B! r -J
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().execute(new HibernateCallback(){ `b9oH^}n j
publicObject doInHibernate @/|sOF;8W
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(Session session)throws HibernateException { y "7TO#
Criteria criteria = G++kUo<
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detachedCriteria.getExecutableCriteria(session); D.$EvUSK<.
return criteria.list(); I0)iC[s8;
} L~vNW6#W
}, true); z[OW%(vrm
} `EWeJ(4Z@
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public int getCountByCriteria(final 4p %`Lv
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DetachedCriteria detachedCriteria){ @,zBZNX
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Integer count = (Integer) $o]suF;3
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getHibernateTemplate().execute(new HibernateCallback(){ %y8w9aGt
publicObject doInHibernate Jz3 q
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(Session session)throws HibernateException { & qd:o}
Criteria criteria = n=hz7tjaz
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detachedCriteria.getExecutableCriteria(session); |#!25qAT
return G-,PsXSwe
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criteria.setProjection(Projections.rowCount w8>T ~Mv
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()).uniqueResult(); _)%4NjWKk
} vuw1ycy)
}, true); ?\^u},HnE|
return count.intValue(); |vEfE{
} paMw88*u
} #9
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: PQA9U|
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用户在web层构造查询条件detachedCriteria,和可选的 i<=@7W
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 _$Z46wHmB
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PaginationSupport的实例ps。 vLpE|QZ s
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ps.getItems()得到已分页好的结果集 j}h50*6KO
ps.getIndexes()得到分页索引的数组 a&Z|3+ZA
ps.getTotalCount()得到总结果数 hoU&'P8
ps.getStartIndex()当前分页索引 Rzb663d
ps.getNextIndex()下一页索引 t'[vN~I'
ps.getPreviousIndex()上一页索引 JziMjR
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 3zh'5qQ
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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 1u&P,&T
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一下代码重构了。 L i< c
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我把原本我的做法也提供出来供大家讨论吧: Dw.>4bA.
gvsS:4N"Nq
首先,为了实现分页查询,我封装了一个Page类: ZE}m\|$
java代码: nNQ\rO
J!yc9Q
aIqNNR
/*Created on 2005-4-14*/ dIM:U:c
package org.flyware.util.page; 7&HP2r
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/** 1f}S:Z
* @author Joa n,V`Y'v)
* $F/&/Aa
*/ QP\vN|r
publicclass Page { Qt@~y'O
tgrQ$Yjk
/** imply if the page has previous page */ 4tq>Lx^5U
privateboolean hasPrePage; 6] <?+#uQ
J'B;
/** imply if the page has next page */ I
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privateboolean hasNextPage; \&e+f#!u
CTPn'P=\C
/** the number of every page */ );,#H`'
privateint everyPage; fcV/co_S6
[5m;L5
/** the total page number */ ?*4]LuK6
privateint totalPage; A= ,q&
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/** the number of current page */ }i/{8OuW
privateint currentPage; 0Fi7|
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/** the begin index of the records by the current w#JF7;
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query */ -lAA,}&+!
privateint beginIndex; *[vf47)r!
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/** The default constructor */ ]%mg(&p4
public Page(){ YY]LK%-
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} )<3WVvB
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/** construct the page by everyPage "bw4{pa+
* @param everyPage m6IZGl7%
* */ 8PQ$X2)
public Page(int everyPage){ $@K+yOq+u
this.everyPage = everyPage; Y-,#3%bT;;
} f$H"|Mbe
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/** The whole constructor */ 1TbKnmTx
public Page(boolean hasPrePage, boolean hasNextPage, Xf#;GYO|2
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int everyPage, int totalPage, 67n1s
int currentPage, int beginIndex){ c)$/Uu
this.hasPrePage = hasPrePage; 'nCBLc8
this.hasNextPage = hasNextPage; y:W$~<E`p
this.everyPage = everyPage; bk>M4l61
this.totalPage = totalPage; y:v0&9L
this.currentPage = currentPage; #z5'5|3
this.beginIndex = beginIndex; {AcKBib
} q=R=z$yr
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/** <p<gx*%
* @return _$, .NK,6
* Returns the beginIndex. G=b`w;oL:
*/ AE<AEq
publicint getBeginIndex(){ !CsoTW9C:
return beginIndex; SJy? ^
} f|b|\/.=
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/** E^|b3G6T
* @param beginIndex }Y-f+qX*
* The beginIndex to set. wuh$=fya
*/ Fa>Y]Y0r
publicvoid setBeginIndex(int beginIndex){ @c{Z?>dUc#
this.beginIndex = beginIndex; 31bKgU{
} j.m-6
4uTYuaCNs
/** +J#H9>To!
* @return }"3L>%Q5
* Returns the currentPage. HD`Gi0
*/ R)<>} y
publicint getCurrentPage(){ FoEZ1O<
return currentPage; Qp-nr]
} 778L[wYe
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/** v#nFPB=z
* @param currentPage [u-~<80
* The currentPage to set. "5>p]u>
*/ v3hNvcMpf
publicvoid setCurrentPage(int currentPage){ 55yP.@i9J
this.currentPage = currentPage; ^@tn+'.
} ZegsV|
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/** X}?cAo2N
* @return {N
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* Returns the everyPage. ,ciNoP*-~%
*/ (-~tb-
publicint getEveryPage(){ |1t30_ /gS
return everyPage; Nzr zLK
} WM>9sJf
d;'@4NX5+
/** c| p
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* @param everyPage ;GvyL>|-~
* The everyPage to set. d;dcLe
*/ d B?I(
publicvoid setEveryPage(int everyPage){ gNxnoOY
this.everyPage = everyPage; 2{&|%1Jg
} IG#=}q
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/** x.45!8Zb
* @return rl6vt*g
* Returns the hasNextPage. VT+GmS
*/ i{%~&!
publicboolean getHasNextPage(){ f\|33)k
return hasNextPage; W'6*$Ron
} &<v#^2S3
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/** Y6g[y\*t
* @param hasNextPage Que)kjp
* The hasNextPage to set. SYl:X
*/ v
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publicvoid setHasNextPage(boolean hasNextPage){ KiCZEA
this.hasNextPage = hasNextPage; 2-{8+*_'
} JU"!qXQr
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/** C#vh2'
* @return FUHa"$Bg
* Returns the hasPrePage. 6,oi(RAf
*/ a2x2N_\=/D
publicboolean getHasPrePage(){ mu:Q2t^
return hasPrePage; hbN*_[
} nY(jN D
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/** OlV>zam
* @param hasPrePage N%>/
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* The hasPrePage to set. a0AIq44
*/ 0w(<pNA
publicvoid setHasPrePage(boolean hasPrePage){ 'kYV}rq;l
this.hasPrePage = hasPrePage; Wp>W?'`
} @^`f~0#:
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/** GO`XKE
* @return Returns the totalPage. Tm`QZh3
* #H5*]"w6I
*/ ,`H=%#
publicint getTotalPage(){ 'jmcS0f
-
return totalPage; dJCu`34Y'|
} uOZ+9x(
@ZT25CD
/** +mAMCM2N
* @param totalPage T@k&YJ
* The totalPage to set. t6js@Ih
*/ :*Ckq~[Hg
publicvoid setTotalPage(int totalPage){ M@csB. '
this.totalPage = totalPage; "7gS*v,r
} (|bht 0
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} ]>:%:-d6
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上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 in B}ydk
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个PageUtil,负责对Page对象进行构造: QmgwIz_
java代码: h2,AcM
yhUc]6`V.H
IK}T.*[
/*Created on 2005-4-14*/ =m-_0xo
package org.flyware.util.page; Ya=QN<
)vPce
import org.apache.commons.logging.Log; .W?POJT
import org.apache.commons.logging.LogFactory; Zwq
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/** b8QW^Z
* @author Joa >)5rOU
* _+^3<MT
*/ 4N#0w]_,>Y
publicclass PageUtil { q9Fc0(&Vf
")Bf^DV
privatestaticfinal Log logger = LogFactory.getLog }rGDM
]`u{^f
(PageUtil.class); 4e*0kItC
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/** )rj.WK.
* Use the origin page to create a new page f1\x>W4z~\
* @param page n1$##=wK]
* @param totalRecords R HF;AX n
* @return R %}k52`
*/ 9Z#37)
publicstatic Page createPage(Page page, int RRq*CLj
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totalRecords){ WqTW@-}I D
return createPage(page.getEveryPage(), Q~*A`h#
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page.getCurrentPage(), totalRecords); ` 6"\.@4
} Jl5<9x
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/** ~2"|4
* the basic page utils not including exception vtvr{Uqo@
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handler OFUN hbg
* @param everyPage q
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* @param currentPage rj{'X /
* @param totalRecords hO(HwG?8t
* @return page e HOm^.gd
*/ #XmN&83_
publicstatic Page createPage(int everyPage, int h`n>6I
i%\nJs*
currentPage, int totalRecords){ b?bIxCA8
everyPage = getEveryPage(everyPage); 6+LXoR'
currentPage = getCurrentPage(currentPage); V7^?jy&&
int beginIndex = getBeginIndex(everyPage, 0@xuxm/i
6tnAE':
currentPage); OTV)#,occ
int totalPage = getTotalPage(everyPage, :I&iDS>u1
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totalRecords); Pu*st=KGB
boolean hasNextPage = hasNextPage(currentPage, h[B
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totalPage); S>H W`
boolean hasPrePage = hasPrePage(currentPage); {= z%('^
s)To#
returnnew Page(hasPrePage, hasNextPage, 1pz6e8p:m
everyPage, totalPage, VK|!aqA{b
currentPage, fSun{?{
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beginIndex); _Juhl^LM;
} 6XX5K@
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privatestaticint getEveryPage(int everyPage){ c 9ghR0WM
return everyPage == 0 ? 10 : everyPage; xw?G?(WO
} t zV"|s=o
JG4&eK$-
privatestaticint getCurrentPage(int currentPage){ $~`(!pa:
return currentPage == 0 ? 1 : currentPage; Mz"kaO
} -<<!eH
i!Ne<Q
privatestaticint getBeginIndex(int everyPage, int \SMH",u
t@4vEKw?.X
currentPage){ C{>?~@z&5
return(currentPage - 1) * everyPage; TbXZU$[c
} zZE?G:isR
-R\}Q"
privatestaticint getTotalPage(int everyPage, int )s^XVs.-
L\"=H4r
totalRecords){ s5z@`M5'm
int totalPage = 0; :;|x'[JoE?
{O"dj;RU
if(totalRecords % everyPage == 0) C6,Bqlio
totalPage = totalRecords / everyPage; c=Z#7?k=Uz
else n09|Jzv9
totalPage = totalRecords / everyPage + 1 ; NtT)Wl
ivGxtx
return totalPage; U'#{v7u
} Xi|v!^IT
Sa<R8X'J
privatestaticboolean hasPrePage(int currentPage){ pF8'S{y
return currentPage == 1 ? false : true; vJcvyz#%1
} 61C&vm
1yE~#KpH
privatestaticboolean hasNextPage(int currentPage, |a"(Ds2U
-,+JE0[
int totalPage){ ~#j`+
return currentPage == totalPage || totalPage == kW(8i}bg
)<Yy.Z_:DC
0 ? false : true; jEI!t^#
} wicg8[T=B
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[hiOFmMJZ-
} g6*}&.&
\zoJr)
Uz62!)
z?i82B[Tm
nF//y}
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。 4<O[d
Ao]F_hZ
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
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CP?\'a"Kt
做法如下: Lv5AtZl}
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 T
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的信息,和一个结果集List: Rn TPU`
java代码: p~e6ah?1
aH>.o 1;
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/*Created on 2005-6-13*/ i\PN
package com.adt.bo;
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tk
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import java.util.List; 2Nj0 Hqjq
*.K}`89T
import org.flyware.util.page.Page; B)c.`cfr*\
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/** f^]2qoN
* @author Joa MW&;{m?2(
*/
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publicclass Result { L'Wcb
=;
9> (8r+
private Page page; +-{HT+W
!X,=RR`zT
private List content; ukPV nk
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/** Jl4zj>8~
* The default constructor apYf,"|9
*/ aFbA=6
public Result(){ E.BMm/WH
super(); N8!B2uPQ
} >=B8PK+<
#q=?Zu^Da
/** <Siz5qQI4
* The constructor using fields 3L;)asF
* S3n$
* @param page &yP9vp="
* @param content N2~Nc"L
*/ XCk \#(VSE
public Result(Page page, List content){ xo]|m\#k5E
this.page = page; g{nu3F}8){
this.content = content; 2R)Y}*VX
} le1'r>E$
s^E%Ukm
/** K!'9wt
* @return Returns the content. he!e~5<@y
*/ ]pFYAe ?
publicList getContent(){ u9?85
return content; 7o;}"Y1
} uODpIxN
J
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/** N7[i443a
* @return Returns the page. J\Sewg9
*/ |}#Rn`*2y
public Page getPage(){ 3ldOOQW%
return page; f^',J@9@
} q 3
9RD
"Z,'NL>&
/** iJ#sg+
* @param content =b6Q2s,i
* The content to set. \.}* s]6
*/ 5Rc
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public void setContent(List content){ fUE jl
this.content = content; 2!l)%F`
} /#.6IV(
=0O`VSb
/** (B[0BjU
* @param page i8EMjLBUR
* The page to set. wG-X833\(
*/ zg "<N
publicvoid setPage(Page page){ 2pZ|+!xc+
this.page = page; ^[5yff 4
} ( vgoG5
} BE:GB?XBH
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qy.Mi{=~:
s% I)+|
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2. 编写业务逻辑接口,并实现它(UserManager, |r6<DEg
X}_kLfP/9
UserManagerImpl) R5|c4v{B
java代码: eB5;wH
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/*Created on 2005-7-15*/ zQ5'q
package com.adt.service; U
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import net.sf.hibernate.HibernateException; ~-|K5
Bg Uf:PT
import org.flyware.util.page.Page; L`3 g5)V
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import com.adt.bo.Result; h=?#D0
^ WidA-
/** DzH1q r
* @author Joa "Q-TLN5(
*/ c]#F^(-A`
publicinterface UserManager { ub7|'+5
yB,$4:C
public Result listUser(Page page)throws 4E<iIA\x
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HibernateException; wxN'Lv=R
t4~Bn<=
} P^T]U bv"
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x^xlH!Sc
ms`R^6Ra
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java代码: 0%#ZupN
~#pQWa5
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/*Created on 2005-7-15*/ r3{Cu z
package com.adt.service.impl; E.zY(# S
Hq ]f$Q6:
import java.util.List; +?DP r
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import net.sf.hibernate.HibernateException; ^yyL4{/
!^:b?M
import org.flyware.util.page.Page; 'QeCJ5p]
import org.flyware.util.page.PageUtil; ,l1A]Wx
9jBP|I{xI
import com.adt.bo.Result; 0X!A'
import com.adt.dao.UserDAO; 1-.6psE
import com.adt.exception.ObjectNotFoundException; D!^&*Ia?2
import com.adt.service.UserManager; :Z3Tyj}4
W;P8=q
/** :G!i]1x<
* @author Joa . =yF
*/ Hyh$-iCa
publicclass UserManagerImpl implements UserManager { dtTQY
xU6)~ae`JW
private UserDAO userDAO; DQui7dr)l
h/?$~OD
/** I($0&Y\De
* @param userDAO The userDAO to set. *6IytWOX5
*/ Wl\.*^`k
publicvoid setUserDAO(UserDAO userDAO){ bbddbRj;
this.userDAO = userDAO; $pr\"!|z
} KP,#x$Bg
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/* (non-Javadoc) "}fJ 2G3
* @see com.adt.service.UserManager#listUser {DlQTgP
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(org.flyware.util.page.Page) +#ufW%ZG
*/ -Ri/I4Xj
public Result listUser(Page page)throws ~ >6d}7xs
(#KSwWo{ed
HibernateException, ObjectNotFoundException { |zd+
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int totalRecords = userDAO.getUserCount(); ~}Xd{afo
if(totalRecords == 0) !Pd@0n4
throw new ObjectNotFoundException "{>BP$Jz
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("userNotExist"); 1u>[0<U~E
page = PageUtil.createPage(page, totalRecords); x
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List users = userDAO.getUserByPage(page); ]L)l5@5^
returnnew Result(page, users); ? DJ/Yw>>3
} OYW:I1K<5
&UrPb%=2H
} \Hb"bv
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= j)5kY`
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\D67J239E
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 l5P!9P
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询,接下来编写UserDAO的代码: &lM=>?
3. UserDAO 和 UserDAOImpl: U</Vcz
java代码: 9696EQ,I
fj"1TtPq#
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/*Created on 2005-7-15*/ U-+o6XX
package com.adt.dao; W=G8l%
%/; *Ewwb
import java.util.List; +6~ut^YiM.
=Vie0TV&h
import org.flyware.util.page.Page; \0j-p
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import net.sf.hibernate.HibernateException; Oz{FM6
Z; 6N7U
/** d%,@,>>)
* @author Joa }vK8P r%
*/ \gCh'3
publicinterface UserDAO extends BaseDAO { {HO,d{{
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publicList getUserByName(String name)throws \RT3#X+
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HibernateException; v]h^0WU
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publicint getUserCount()throws HibernateException; CXiDe)|<E
'><I|c}
publicList getUserByPage(Page page)throws DMdVE P"m
h~`^H9?M
HibernateException; kY?w] lS)t
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} )Szn,
+ *)Kyk
xYp-Y"a.
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java代码:
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/*Created on 2005-7-15*/ =|LB,REN
package com.adt.dao.impl; imc1rY!~'
~e<^jhpJ
import java.util.List; {[pzqzL6
J7pF*2
import org.flyware.util.page.Page; ]xxE_B7
]y9u5H^
import net.sf.hibernate.HibernateException; \RS0mb
import net.sf.hibernate.Query; )tm%0z7R
2WUl8?f2Y
import com.adt.dao.UserDAO; w,*#z
&|fPskpy
/** XwZR
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* @author Joa ,K15KN.'
*/ RF[Uy?es
public class UserDAOImpl extends BaseDAOHibernateImpl s5\<D7
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A
implements UserDAO { Nt,:`o |
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/* (non-Javadoc) 0" F\V
* @see com.adt.dao.UserDAO#getUserByName %bp'`B=
^U9b)KA
(java.lang.String) SuA
@S
*/ cO8yu`4!e
publicList getUserByName(String name)throws B7.<A#y2
}SFmv},Ij
HibernateException { 8b"vXNB.f
String querySentence = "FROM user in class ':|E$@$W
,`!>.E.
com.adt.po.User WHERE user.name=:name"; \E1CQP-
Query query = getSession().createQuery =F% <W7
kq*IC&y
(querySentence); weMufT
query.setParameter("name", name); LJSx~)@
return query.list(); ]+5Y\~I
} l0PXU)>C
,&iEn}xG7i
/* (non-Javadoc) /b]+RXvxj
* @see com.adt.dao.UserDAO#getUserCount() #y8Esik
*/ |JiN;
O+K
publicint getUserCount()throws HibernateException { j9/hZqo
int count = 0; siOyp]
String querySentence = "SELECT count(*) FROM BPSie0
+3J5j+
user in class com.adt.po.User"; uHuL9Q^
Query query = getSession().createQuery
qN'%q+n
0HI0/Tvu$<
(querySentence); W[LQ$uj
count = ((Integer)query.iterate().next p^C$(}Yh
7O~hA*Z
()).intValue(); .[
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return count; <9[>+X
} #Cb~-2:+7
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/* (non-Javadoc) r*c x_**
* @see com.adt.dao.UserDAO#getUserByPage =%S*h)}@
YRu/KUT$ 7
(org.flyware.util.page.Page) VVe^s|~Z
*/ a|ZJzuqo
publicList getUserByPage(Page page)throws v2ab84
C*
,Vy_%f
HibernateException { $\aJ.N6rb
String querySentence = "FROM user in class 4|hfzCjMI
7g4IAsoD
com.adt.po.User"; ?NxaJ^
Query query = getSession().createQuery Xc9NM1bp=
{>d\
(querySentence); MFz6y":~
query.setFirstResult(page.getBeginIndex()) Cy5M0{
.setMaxResults(page.getEveryPage()); b2^O$l
return query.list(); C_ W%]8u
} f9HoQDFsM
n{!=gR.v.
} gMPvzBpP
#<5i/5&
2E.D0E Cu
z>HM$n`YD
^qtJcMK+hq
至此,一个完整的分页程序完成。前台的只需要调用 [M?&JA