Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 K|Kc.
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 E{B8+T:3
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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>_~zW nc
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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 c1>:|D7w
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分页支持类: FQp@/H^
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java代码: D&C83^m
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package com.javaeye.common.util; X) O9PQ
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import java.util.List; -z6{!
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publicclass PaginationSupport { }]K^b1Fs5
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publicfinalstaticint PAGESIZE = 30; R'e>YDC
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privateint pageSize = PAGESIZE; '}pe$=
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privateList items; FcI ZG _
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privateint totalCount; E2%{?o
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privateint[] indexes = newint[0]; 898=9`7e
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privateint startIndex = 0; pGHn
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public PaginationSupport(List items, int 6f^q >YP
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totalCount){ |on$)vm
setPageSize(PAGESIZE); 9&VfbrBM
setTotalCount(totalCount); Du7DMo=l
setItems(items); o+F]80CH
setStartIndex(0); )Co&(;zf
} f0Zn31c^
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public PaginationSupport(List items, int ?x-:JME0
{DVu* %|
totalCount, int startIndex){ H7&bUt/
setPageSize(PAGESIZE);
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setTotalCount(totalCount); ^\Gukkmh}
setItems(items); /GUbc
setStartIndex(startIndex); s^6"qhTa
} xTV3U9 v
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public PaginationSupport(List items, int R.rxpJ+kU
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totalCount, int pageSize, int startIndex){ Z.x9SEe1t
setPageSize(pageSize); @Z{!T)#}j
setTotalCount(totalCount); o%1dbbh
setItems(items); q(iM=IeiN
setStartIndex(startIndex); XeRbn
} `^#V1kRmH
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publicList getItems(){ %hO/2u
return items; Uc>$w?oA
} ~Q36lR
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publicvoid setItems(List items){ T
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this.items = items; !y 7SCz
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} m
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publicint getPageSize(){ sPoH12?AL
return pageSize; =bDy :yY}
} }2CVA.Qm!
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publicvoid setPageSize(int pageSize){ OEwKT7CX
this.pageSize = pageSize; q\q8xF~[p
} .*acw
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publicint getTotalCount(){ EKTn$k=
return totalCount; z:a%kZQ!0
} XZ1oV?Z4
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publicvoid setTotalCount(int totalCount){ uFH ]w]X
if(totalCount > 0){ r)Dln5F
this.totalCount = totalCount; ImZ!8#
int count = totalCount / )e6)~3[^
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pageSize; t;2\(_A
if(totalCount % pageSize > 0) s+RSAyU
count++; M+ljg&fy
indexes = newint[count]; f 3t&Bcw$
for(int i = 0; i < count; i++){ c u:1|gt
indexes = pageSize * Ed$;#4
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i; 64jFbbd-/
} O>)Fl42IeD
}else{ p.50BcDg
this.totalCount = 0; 2zQ62t}
} V \4zK$]
} ` 0}z
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publicint[] getIndexes(){ [n!5!/g>j
return indexes; XI"8d.VR
} K[/sVaPZ
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publicvoid setIndexes(int[] indexes){ 3|qT.QR`Z
this.indexes = indexes; hCvK2Xu
} R3,O;9i
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publicint getStartIndex(){ `N.^+Mvx-
return startIndex; I C?bqC+
} $-Wn|w+h<a
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publicvoid setStartIndex(int startIndex){ ~n<U8cm O
if(totalCount <= 0) x;;
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this.startIndex = 0; _t'S<jTI
elseif(startIndex >= totalCount) $wq[W,'#L
this.startIndex = indexes Q#a<T4l
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[indexes.length - 1]; g(`m#&P>G
elseif(startIndex < 0) Q^c)T>OAI
this.startIndex = 0; }>T$2"pf
else{ R_|Sg
this.startIndex = indexes Mb0l*'ZF
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[startIndex / pageSize]; 7F!(60xY
} =mWr8p-H
} 40ZHDtIu<
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publicint getNextIndex(){ W7 iml|WV0
int nextIndex = getStartIndex() + +q NX/F
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pageSize; t!S ja
if(nextIndex >= totalCount) 9+!1jTGSkf
return getStartIndex(); |yT-N3H@
else AXmW7/Sj"
return nextIndex; ,-[e{=Cz
} d \[cFe1d
/j|Rz5@=
publicint getPreviousIndex(){ fP:26pK^
int previousIndex = getStartIndex() - h'D-e5i
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pageSize; #;*0 Pwe`
if(previousIndex < 0) qC;1ND
return0; ]u\K}n6[q
else GI ~<clhf
return previousIndex; C>bd
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} tn@MOOPl
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} p(J,fus
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抽象业务类 V_.n G;
java代码: <R%]9#re
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/** Kq. MmR!gl
* Created on 2005-7-12 mxxuD"5
*/ VUD ?iv7
package com.javaeye.common.business; H[S 4o,
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import java.io.Serializable; n@"h^-
import java.util.List; /`)>W :
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import org.hibernate.Criteria; #4Z]/D2G
import org.hibernate.HibernateException; kCoTz"Z-
import org.hibernate.Session; N4z(2.
import org.hibernate.criterion.DetachedCriteria; %M/rpEE"b%
import org.hibernate.criterion.Projections; -N4km5
import XX@@tzN
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org.springframework.orm.hibernate3.HibernateCallback; )X
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import }>|!Mf]W?R
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org.springframework.orm.hibernate3.support.HibernateDaoS 1`;,_>8
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upport; ecjjCt2S
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import com.javaeye.common.util.PaginationSupport; '=^$;3Z
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public abstract class AbstractManager extends {8YNmxF#
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HibernateDaoSupport { E$w2SQ
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privateboolean cacheQueries = false; nKP[U=ac
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privateString queryCacheRegion; @aX$}
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publicvoid setCacheQueries(boolean ^9 g+\W
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cacheQueries){ P%- @AmO^_
this.cacheQueries = cacheQueries; )w.\xA~|
} k~<b~VcU
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publicvoid setQueryCacheRegion(String p%_m!
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queryCacheRegion){ ,2I8,MOg
this.queryCacheRegion = c,\!<4
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queryCacheRegion; 0!^vQ
} <o\2-fWvY
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publicvoid save(finalObject entity){ Xw|t.0
getHibernateTemplate().save(entity); ~gjREl,+D#
} H /kSFf{
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publicvoid persist(finalObject entity){ &;D(VdSr9
getHibernateTemplate().save(entity); w,'"2^Cwy
} XehpW}2\
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publicvoid update(finalObject entity){ o,#[Se*n
getHibernateTemplate().update(entity); D m|_;iO,
} %S2^i3
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publicvoid delete(finalObject entity){ 0%9Nf!j
getHibernateTemplate().delete(entity); iyRB}[y
} .Y?/J,Ch
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publicObject load(finalClass entity, 2`-y zm
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finalSerializable id){ RnA>oKc
return getHibernateTemplate().load j\ dY
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(entity, id); LHt{y3l]
} ]Gm$0uS
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publicObject get(finalClass entity, ]lKQwpX3
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finalSerializable id){ q
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return getHibernateTemplate().get XuQ7nlbnq
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(entity, id); UP@a
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} sw(dd01a
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publicList findAll(finalClass entity){ }P5zf$
return getHibernateTemplate().find("from
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" + entity.getName()); !_EaF`oh(
} Mbt}G|;8H7
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publicList findByNamedQuery(finalString XYKWOrkQqa
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namedQuery){ B" -gK20vY
return getHibernateTemplate :uAW
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().findByNamedQuery(namedQuery); <By6%<JTn
} p8>.Q/4
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publicList findByNamedQuery(finalString query, Pgy&/-u
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finalObject parameter){ m"2KAq61
return getHibernateTemplate FyZa1%Tv@
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().findByNamedQuery(query, parameter); H$:Z`CQt<
} VtR?/+8X
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publicList findByNamedQuery(finalString query, MI|51&m
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finalObject[] parameters){ d2Z kchf
return getHibernateTemplate Y4%Bx8
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().findByNamedQuery(query, parameters); B%v2)+?@
} X(-e-:B4;
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publicList find(finalString query){ kAbkhZ1^
return getHibernateTemplate().find z2m%L0
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(query); 1PMBo=SUe8
} d9zI
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publicList find(finalString query, finalObject @#T*OH
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parameter){ k)W8%=R
return getHibernateTemplate().find BReNhk)S
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(query, parameter); 6]i"lqb
} 8{5Y%InL
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public PaginationSupport findPageByCriteria vG(Gs=.U
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(final DetachedCriteria detachedCriteria){ }+[H~8)5
return findPageByCriteria y.AF90Q>)
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); KzRw)P
} [sC]<2 r
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public PaginationSupport findPageByCriteria w][1C\8m
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(final DetachedCriteria detachedCriteria, finalint G?LPj*=$?
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startIndex){ 8K!
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return findPageByCriteria kL.JrbM"
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(detachedCriteria, PaginationSupport.PAGESIZE, 10v4k<xb
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startIndex); Q 'R@'W9
} })OgsBk
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public PaginationSupport findPageByCriteria eRC
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(final DetachedCriteria detachedCriteria, finalint k
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pageSize, .*u, !1u
finalint startIndex){ nXDU8|"
return(PaginationSupport) <|~8Ezd
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getHibernateTemplate().execute(new HibernateCallback(){ 5Sd+Cc
publicObject doInHibernate qp*C%U
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(Session session)throws HibernateException { LL5n{#)N
Criteria criteria = I_mnXd;n
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detachedCriteria.getExecutableCriteria(session); a3i4eGT -
int totalCount = 2R&msdF
}
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((Integer) criteria.setProjection(Projections.rowCount \*x]xc/^
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()).uniqueResult()).intValue(); /dpEL9K
criteria.setProjection YEoQIR
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(null); 'c 0]8Y4
List items = )s6pOxWx
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criteria.setFirstResult(startIndex).setMaxResults "nXL7N0
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(pageSize).list(); $LLkYOwI
PaginationSupport ps = A-\OB
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new PaginationSupport(items, totalCount, pageSize, F}P+3IaE
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startIndex); n7`R+4/s
return ps; !es?GJq`
} [z$th
}, true); OD!b*Iy|
} 4y&%YLMpl
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public List findAllByCriteria(final {-IH?!&v
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DetachedCriteria detachedCriteria){ (J8(_MF
return(List) getHibernateTemplate Tj}H3/2
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().execute(new HibernateCallback(){ <zE,T@c
publicObject doInHibernate >K$9(
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(Session session)throws HibernateException { ~=~|@K
Criteria criteria = Sw<@u+Z;%
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detachedCriteria.getExecutableCriteria(session); gT$`a
return criteria.list(); mGZ^K,)&OR
} ZI4[v>
}, true); E7-il;`cKn
} g$<Sh.4A
Md_S};!QN6
public int getCountByCriteria(final v'(p."g
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DetachedCriteria detachedCriteria){ I!?-lI@(
Integer count = (Integer) Y.&nxT95=
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getHibernateTemplate().execute(new HibernateCallback(){ t<5$85Y~
publicObject doInHibernate hnag<=
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(Session session)throws HibernateException { r9<OB`)3+
Criteria criteria = rf_(pp)
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detachedCriteria.getExecutableCriteria(session); $8gj}0}eH
return x5_V5A/@LU
#?8dInu>
criteria.setProjection(Projections.rowCount _]btsv\)f
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()).uniqueResult(); [%'yHb~<
} Eb66GXF[
}, true); o.IJ4'}aN
return count.intValue(); e E:J
} WPT0=Hqp7
} U_ELeW5@
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用户在web层构造查询条件detachedCriteria,和可选的 9<BC6M_/
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 8UiRirw
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PaginationSupport的实例ps。 W8{g<.
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ps.getItems()得到已分页好的结果集 34S0W]V
ps.getIndexes()得到分页索引的数组 &Z!O
ps.getTotalCount()得到总结果数 Q!7il<S
ps.getStartIndex()当前分页索引 G^E"#F
ps.getNextIndex()下一页索引 ,@1rP 55
ps.getPreviousIndex()上一页索引 ZoJ_I
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 aQzDOeTi
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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 l*eJa38
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一下代码重构了。 DJ)Q,l*|N9
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我把原本我的做法也提供出来供大家讨论吧: _Q XC5i
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首先,为了实现分页查询,我封装了一个Page类: M&au A
java代码: fCC^hB]'
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/*Created on 2005-4-14*/ Egy#_ RT{
package org.flyware.util.page; .d
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/** b ]A9$-
* @author Joa NVyel*QE
* v+\&8)W=
*/ Cn6<I {`\
publicclass Page { R^u 1(SF
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/** imply if the page has previous page */ g"b{M
privateboolean hasPrePage; ,j3Yvn W
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/** imply if the page has next page */ {\:"OcP #
privateboolean hasNextPage; |.]sL0;4Z
3i\<#{
/** the number of every page */ k5M3g*
privateint everyPage; :c03"jvYE
(rTn6[*
/** the total page number */ lqaOLZH
privateint totalPage; $)or{Z$&
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/** the number of current page */ 3UXaA;
privateint currentPage; 7LotN6H
*z?Vy<u G
/** the begin index of the records by the current P|U9f6^3
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query */ 2Q bCH}
privateint beginIndex; +g.lLb*#
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/** The default constructor */ <rQ+ErDA
public Page(){ opaRk.p
7&O0
} YB`1S
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/** construct the page by everyPage cmcR@zv
* @param everyPage "+dByaY
* */ -K%hug
public Page(int everyPage){ 1iLrKA
this.everyPage = everyPage; e-E0Bp
} ~7;AV(\%e
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/** The whole constructor */ /TEE<\"
public Page(boolean hasPrePage, boolean hasNextPage, j'IZ etT
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int everyPage, int totalPage, W]B75
int currentPage, int beginIndex){ =PM6:3aKh
this.hasPrePage = hasPrePage; [\BLb8
this.hasNextPage = hasNextPage; B!j7vXM2
this.everyPage = everyPage; MP6Py@J45
this.totalPage = totalPage; ;N(9nX}%)
this.currentPage = currentPage; 7gnrLc$]O
this.beginIndex = beginIndex; U*Sjb%
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} r)]8zK4;=
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/** 9YQYg@+R
* @return x?6
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* Returns the beginIndex. br3r!Vuz/-
*/ fVvB8[(;~
publicint getBeginIndex(){ bCfw,V{sce
return beginIndex; T8t_+|(
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} ,v@C=4'm
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/** n=iL6Yu(
* @param beginIndex =zsA@UM0
* The beginIndex to set. @h
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*/
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publicvoid setBeginIndex(int beginIndex){ [sc4ULS &
this.beginIndex = beginIndex; {kOTQG?y
} 8M6wc394
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/** x\K9|_!
* @return . UaLP
* Returns the currentPage. Rm&4Pku
*/ XF Cwa
publicint getCurrentPage(){ 9%iv?/o*L
return currentPage; aGs\zCAP
} (dnaT-M3
7*>(C*q=
/**
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* @param currentPage ]!'}{[1}
* The currentPage to set. L (@".{T
*/ EC8 Fapy
publicvoid setCurrentPage(int currentPage){ @Wl2E.)K;
this.currentPage = currentPage; =N^j:t
} U
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/** N2.(0 G
* @return spG3"Eodi
* Returns the everyPage. MZWicfUy
*/ c`s ]ciC
publicint getEveryPage(){ (yO8G-Z0
return everyPage; 'z$!9ufY,
} Aa!#=V1d
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/** j21>\K!p
* @param everyPage aS/ MlMf
* The everyPage to set. ZxoAf;U~
*/ AYHefAF<w
publicvoid setEveryPage(int everyPage){ J`'wprSBb
this.everyPage = everyPage; @3_."-d
} ;y]BXW&l&
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/** )u>/:
* @return Lg2z `uv
* Returns the hasNextPage. $*qQ/hi
*/ <!a%GI
publicboolean getHasNextPage(){ DTN)#GCtF
return hasNextPage; f\X7h6k8{
} ]&_z@Z.i
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/** 20`QA
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* @param hasNextPage Lgrpy
* The hasNextPage to set. a_(fqoW
*/ ^X|Bzz)
publicvoid setHasNextPage(boolean hasNextPage){ &'"dYZj{
this.hasNextPage = hasNextPage; $TY1'#1U;
} uZXG"
\}:;kO4f
/** 6QX2&[qWS
* @return z|v/hUrD
* Returns the hasPrePage. 5-! Zm]
*/ {1L{
publicboolean getHasPrePage(){ 1qE*M7_:E>
return hasPrePage; \:Z8"~G
} owe6ge7m
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/** 60X))MyN
* @param hasPrePage ;R*tT%Z,
* The hasPrePage to set. 4YyVh.x
*/ W0\
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publicvoid setHasPrePage(boolean hasPrePage){ b@ OF
this.hasPrePage = hasPrePage; PwS7!dzH-
} fp2uk3Bm[
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/** @XN*H- |
* @return Returns the totalPage. (dHil#l
*
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*/ h:Hpz
publicint getTotalPage(){ 4=C7V,a
return totalPage; !~-@p?kW/
} 4%>2>5
v
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/** KOit7+Q
* @param totalPage b>'y[P!
* The totalPage to set. _qjkiKm?1F
*/ UUR` m
publicvoid setTotalPage(int totalPage){ +qee8QH
this.totalPage = totalPage; 5K {{o''
} >slGicZ0
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} *DuP~8
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HC>MCwx=r
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Wq"^ {
上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 , A;wLI
VL8yL`~zc.
个PageUtil,负责对Page对象进行构造: 3)_(t.$D
java代码: @
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/*Created on 2005-4-14*/ Q)93+1]
package org.flyware.util.page; ]?UK98uS\A
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import org.apache.commons.logging.Log; W+ v#m>G
import org.apache.commons.logging.LogFactory; { v#wU
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/** {LqahO*
* @author Joa ,`U'q|b
* s/0~!0
*/ &e;GoJ
publicclass PageUtil { 8=WX`*-uH
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privatestaticfinal Log logger = LogFactory.getLog ]<:qMLg
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(PageUtil.class); ]Nb~-)t%B
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/** DNGj8 1'c
* Use the origin page to create a new page x?n13C
* @param page KpfQ=~'
* @param totalRecords "q3W&@
* @return 3GM9ZPeN:
*/ Km!~zG7<
publicstatic Page createPage(Page page, int .aD=d\
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totalRecords){ rk< 3QXv
return createPage(page.getEveryPage(), lzK,VZ=mM
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page.getCurrentPage(), totalRecords); %d2\4{{S
} 3$h yV{
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/** y /OPN<=*
* the basic page utils not including exception }=
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handler cp L '
* @param everyPage ]Aa.=
* @param currentPage 'I5~<"E
* @param totalRecords baz~luM
* @return page /tu\q
*/ }J(o!2.
publicstatic Page createPage(int everyPage, int 9y`Vg
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currentPage, int totalRecords){ r"=6s/q7
everyPage = getEveryPage(everyPage); ;Ff5ooL{
currentPage = getCurrentPage(currentPage); nPj
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int beginIndex = getBeginIndex(everyPage, &0JCZ/e
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currentPage); n--w-1
int totalPage = getTotalPage(everyPage, `Uy4> ?
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totalRecords); m
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boolean hasNextPage = hasNextPage(currentPage, VTs
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UCI !>G
totalPage); `m=u2kxY
boolean hasPrePage = hasPrePage(currentPage); 'h{| ]
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returnnew Page(hasPrePage, hasNextPage, nW!pOTJq21
everyPage, totalPage, +~!\;71:f
currentPage, oh.8WlI
#6F/:j;
beginIndex); Qcs>BOV~
} *S] K@g
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privatestaticint getEveryPage(int everyPage){ z-`-0@/A$
return everyPage == 0 ? 10 : everyPage; GCv*a[8?n
} EbMG9
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privatestaticint getCurrentPage(int currentPage){ *;Gn od<
return currentPage == 0 ? 1 : currentPage; BiCC72oig
} kqt.?iJw
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privatestaticint getBeginIndex(int everyPage, int ]hjA,p@Q
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currentPage){ q
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return(currentPage - 1) * everyPage; GcCMCR3
} Wv-nRDNG
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privatestaticint getTotalPage(int everyPage, int G_)(?
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totalRecords){ ^eY% T5K
int totalPage = 0; ;/)u/[KAv
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if(totalRecords % everyPage == 0) uH=^ILN.
totalPage = totalRecords / everyPage; 2y@y<38
else N]7#Q.(~
totalPage = totalRecords / everyPage + 1 ; P#N@W_""YD
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return totalPage; VY_<c 98v
} 82A[[^`
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privatestaticboolean hasPrePage(int currentPage){ XpoEZ|0
return currentPage == 1 ? false : true; ;.#l[
} ^UiSezcI
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privatestaticboolean hasNextPage(int currentPage, C ehz]C
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int totalPage){ _0
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return currentPage == totalPage || totalPage == ;vLg4k
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0 ? false : true; X2S:"0?7
} bbAJ5EqL
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} cH{[\F"Eb
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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。 5.X`[/]<r
z2Kvp"-}
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 !Ng~;2GoA
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做法如下:
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1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 +?R!
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的信息,和一个结果集List: 5dem~YY5
java代码: d;WXlE;
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/*Created on 2005-6-13*/ rWnZ It"
package com.adt.bo; U1~6 o"1H
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import java.util.List; +VdC g_
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import org.flyware.util.page.Page; sH`(y)`_
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/** Sz3Tp5b
* @author Joa EL+P,q/b
*/ #5/.n.X"
publicclass Result { ac< hz0
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private Page page; '>0rp\jC
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private List content; `6B jNV
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/** ,!'L~{
* The default constructor iQj2aK Gs
*/ [|E|(@J
public Result(){ =!Ce#p?h,
super(); 1 wB2:o<
} HA W57N
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/** P
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* The constructor using fields Ki{]5Rz
* zv[pfD7a
* @param page +4--Dl?
* @param content
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*/ /By`FW Y
public Result(Page page, List content){ dp'xd>m
this.page = page; b am*&E%0K
this.content = content; Z9vJF.clO
} [S#QGB19
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/** Wi3St`$
* @return Returns the content. +(qs{07A$
*/ +PGtO9}B
publicList getContent(){ 3I%F,-r
return content; @ - _lw
} DgiMMmpE
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/** cJ#|mzup
* @return Returns the page. hm+,o_+
*/ B9Y*'hmI
public Page getPage(){ iZbY@-3fc
return page; P]wCC`qi
} wS%aN@ay3
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/** m#kJ((~
* @param content jUg.Y98
* The content to set. f1}am<
*/ q]r?s%x
public void setContent(List content){ byB
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this.content = content; ZuIw4u(9
} 'hn=X7
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/** NiPa-yRh
* @param page z=/xv},
* The page to set. Z;4pI@u
*/ ->29Tns
publicvoid setPage(Page page){ sn6:\X<[
this.page = page; A(dWAe,
} ~D$?.,=l
} _}RzJKl@
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2. 编写业务逻辑接口,并实现它(UserManager, y%4G[Dz
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UserManagerImpl) vbT,!
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java代码: eTrIN,4
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/*Created on 2005-7-15*/ 3$Y(swc
package com.adt.service; ,j|9Bs
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import net.sf.hibernate.HibernateException; $&l}
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import org.flyware.util.page.Page; ~Vf+@_G8`
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import com.adt.bo.Result; "spAYk\
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/** :6}y gL*i
* @author Joa AtU!8Z
*/ L@t}UC
publicinterface UserManager { n fU\l<
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public Result listUser(Page page)throws (ev(~Wc
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HibernateException; vsU1Lzna6@
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} wf[B -2q)
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java代码: @C34^\aH+
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/*Created on 2005-7-15*/ b9(_bsc
package com.adt.service.impl; q=H
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import java.util.List; ^Cm9[1p
2kS]:4)T
import net.sf.hibernate.HibernateException; yS)73s/MrY
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import org.flyware.util.page.Page; qbwX*E~;
import org.flyware.util.page.PageUtil; ZI8*PX%2
;jEDGKLq
import com.adt.bo.Result; cJ>
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import com.adt.dao.UserDAO; ;[ag|YU$Y
import com.adt.exception.ObjectNotFoundException; S3oSc<&2
import com.adt.service.UserManager; (4WAoye |
3TDjWW;#~
/** @TTB$
* @author Joa }%;o#!<N(@
*/ |*w}bT(PfR
publicclass UserManagerImpl implements UserManager { `?H yDny
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private UserDAO userDAO; ,iQRf@#W_b
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/** 6zGM[2
* @param userDAO The userDAO to set. K Qz.g3,
*/ -/O_wqm#
publicvoid setUserDAO(UserDAO userDAO){ ^lp#j;Df
this.userDAO = userDAO; nhm)P_p
} j
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/* (non-Javadoc) \UF/_'=K
* @see com.adt.service.UserManager#listUser }eO{+{D+
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(org.flyware.util.page.Page) yG`J3++
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*/ `<z"BGQ
public Result listUser(Page page)throws Wt%+q{
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HibernateException, ObjectNotFoundException { >4.K>U?0FC
int totalRecords = userDAO.getUserCount(); el;ey Ga
if(totalRecords == 0) #Pf?.NrTn
throw new ObjectNotFoundException *88Q6=Mm
aB N^J_
("userNotExist"); ~rN:4Q]/
page = PageUtil.createPage(page, totalRecords); &`RD5uml
List users = userDAO.getUserByPage(page); k\qF> =
returnnew Result(page, users); )M!6y%b67
} :U}.
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} _=wu>h&7
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其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 );]9M~$
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询,接下来编写UserDAO的代码: d3nMeAI AO
3. UserDAO 和 UserDAOImpl: 8)wxc1
java代码: FKX+
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/*Created on 2005-7-15*/ 3Dd"qON!
package com.adt.dao; J*n Q(*e
;!ICLkc$
import java.util.List; DaN=NURDV
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import org.flyware.util.page.Page; KXQ &u{[<
7j
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import net.sf.hibernate.HibernateException; +4N7 _Y
mip2=7M|C
/** $ e<1 08)]
* @author Joa &7i o/d\/
*/ s?:&#
publicinterface UserDAO extends BaseDAO { c,K)*HB
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publicList getUserByName(String name)throws PLkwtDi+&
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HibernateException; rW8.bMmM
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publicint getUserCount()throws HibernateException; LR:v$3 G(
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publicList getUserByPage(Page page)throws *CIR$sS
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HibernateException; G` _LD+
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} )\qA[rTG
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. paA0j
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6 cF~8
java代码: E=H>|FgS
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/*Created on 2005-7-15*/ y&-1SP<
package com.adt.dao.impl; IpJMq^Z
klwC.=?(j"
import java.util.List; PQkFzyk
X\-IAv
import org.flyware.util.page.Page; _VjfH2Y
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import net.sf.hibernate.HibernateException; #K:!s<_"
import net.sf.hibernate.Query; WS!:w'rzr
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import com.adt.dao.UserDAO; z frEM
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/** P?#I9y7iP
* @author Joa _|'e Az
*/ hyHeyDO2
public class UserDAOImpl extends BaseDAOHibernateImpl z!M8lpIM
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implements UserDAO { hLv~N}
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/* (non-Javadoc) '^npZa'%sW
* @see com.adt.dao.UserDAO#getUserByName U9*uXD1\
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(java.lang.String) _5t~g_(1OK
*/ +;T `uOF}
publicList getUserByName(String name)throws &}:]uC
;*H@E(g
HibernateException { D?Mj<||
String querySentence = "FROM user in class RjcU0$Hi
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com.adt.po.User WHERE user.name=:name"; fLtN-w6t
Query query = getSession().createQuery +2KYtyI
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(querySentence); ~$WBc qo
query.setParameter("name", name); c\J?J>xz
return query.list(); !Qqi%
} eTeZ^G
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/* (non-Javadoc) @(m+B\
* @see com.adt.dao.UserDAO#getUserCount() JNJ96wnX1
*/ N<$dbqoT|
publicint getUserCount()throws HibernateException { V,*<E &+
int count = 0; |[ )e5Xhd
String querySentence = "SELECT count(*) FROM (uxe<'Co|
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user in class com.adt.po.User"; |=o)|z2
Query query = getSession().createQuery ~l^Q~W-+
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(querySentence); MXsCm(
count = ((Integer)query.iterate().next mBrH`!
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()).intValue(); +sW;p?K7eO
return count; mw\
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} :j)v=qul
v7h!'U[/
/* (non-Javadoc) =hP7Hea(N
* @see com.adt.dao.UserDAO#getUserByPage {\-9^RL
0E<