Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 q)<5&|V
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 #; }IHAR
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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 v`x~O+
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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 Mk,8v],-Tj
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分页支持类: :qgdn,Me
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java代码: ?R"5 .3
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package com.javaeye.common.util; UkXc7D^jwm
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import java.util.List; f&^Ea-c
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publicclass PaginationSupport { X] Tb4
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publicfinalstaticint PAGESIZE = 30; %k$+t
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privateint pageSize = PAGESIZE; !dVcnK1
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privateList items; b39;Sv|#
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privateint totalCount; D|9B1>A,m
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privateint[] indexes = newint[0]; Y5ebpw+B-
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privateint startIndex = 0; V~e1CZ(2X
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public PaginationSupport(List items, int zS?i@e
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totalCount){ K=`*cSU>
setPageSize(PAGESIZE); PMXnupt
setTotalCount(totalCount); {} vl^b
setItems(items); JBb}{fo~
setStartIndex(0); \4zvknk<
} r]0 o
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public PaginationSupport(List items, int aoF>{Z4&B
8Bhot,u'T
totalCount, int startIndex){ s8eiq`6\H}
setPageSize(PAGESIZE); r<C^hs&]
setTotalCount(totalCount); o~es>;
setItems(items); H@aCo(#
setStartIndex(startIndex); #Kn7
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} bmT J
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public PaginationSupport(List items, int "lN<v=
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totalCount, int pageSize, int startIndex){ rD$7;
setPageSize(pageSize); mjs*Z{_F^
setTotalCount(totalCount); 66Hu<3X P
setItems(items); %$sWNn
setStartIndex(startIndex); GIZNHG
} /hI#6k8o_
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publicList getItems(){ :I<%.|8
return items; 8eOQRC33
} *bv
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publicvoid setItems(List items){ ,FBF;zED
this.items = items; {-17;M$
} ?kS5=&<
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publicint getPageSize(){ JZP2NB_xt
return pageSize; -*yj[?6
} Iun!rv
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publicvoid setPageSize(int pageSize){ +[~\\X
this.pageSize = pageSize; 4S"K%2'O
} 2sittP
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publicint getTotalCount(){ ;iS}<TA
return totalCount; zh50]tX
} R
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publicvoid setTotalCount(int totalCount){ ,LzS"lmmo
if(totalCount > 0){ |h6@hB\
this.totalCount = totalCount; gVq{g,yi
int count = totalCount / L{gFk{@W
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pageSize; 9lA YCsX
if(totalCount % pageSize > 0) U*a!Gn7l
count++; c#{<|
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indexes = newint[count]; F1%'
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for(int i = 0; i < count; i++){ 7g&_`(
indexes = pageSize * #UXmTrZ.
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} < W&~tVv
}else{ (iWNvVGS
this.totalCount = 0; Po^2+s(fY
} n\cP17dr
} 88G[XkL$2
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publicint[] getIndexes(){ `yC
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return indexes; eJy@N
} #c!(97l6o
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publicvoid setIndexes(int[] indexes){ *]Vx=7D
this.indexes = indexes; ^i:%;oeG
} 4Nq n47|>e
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publicint getStartIndex(){ =BGc@:2
return startIndex; z,]fR
} A#jiCIc
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publicvoid setStartIndex(int startIndex){ ]pB~&0jg
if(totalCount <= 0) *><]
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this.startIndex = 0; wbr"z7}
elseif(startIndex >= totalCount) .3HC*E.e
this.startIndex = indexes PfuYT_p4s
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[indexes.length - 1]; jpBE| Nm
elseif(startIndex < 0) 4|:{apH
this.startIndex = 0; $6'xRUx X
else{ W
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this.startIndex = indexes '0o`<xW
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[startIndex / pageSize]; z1V 0WDVm
} BB|{VwN
} :fj}J)9'xW
;
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publicint getNextIndex(){ UT^t7MY#O
int nextIndex = getStartIndex() + <!w-op2@ir
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pageSize; {1SxM /
if(nextIndex >= totalCount) oY0*T9vv+
return getStartIndex();
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else -k<.Q=]<t
return nextIndex; %[p[F~Z^Z
} c6lEWC:
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publicint getPreviousIndex(){ (bT\HW%m
int previousIndex = getStartIndex() - >ueJ+sgH
*#2`b%qh\M
pageSize; Qy3e,9nS
if(previousIndex < 0) q2hZ1o
return0; x b _C1n
else :+R||qi
return previousIndex; :*oI"U*f
} A: @=?(lI3
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} OI`Lb\8pP
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抽象业务类 WV&BZ:H
java代码: }%jb/@~
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/** + S%+Ku
* Created on 2005-7-12 +h9CcBd
*/ ,,G0}N@7s
package com.javaeye.common.business; U2Ur N?T
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import java.io.Serializable; R=9j+74U
import java.util.List; #
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import org.hibernate.Criteria; \T[*|"RFZ
import org.hibernate.HibernateException; chiQ+
import org.hibernate.Session; Ar):D#D
import org.hibernate.criterion.DetachedCriteria; /Fv1Z=:r
import org.hibernate.criterion.Projections; zBoU;d%p>
import | z('yy$
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org.springframework.orm.hibernate3.HibernateCallback; 5Y,e}+I>
import F1,pAtA
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org.springframework.orm.hibernate3.support.HibernateDaoS p@Qzg
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upport; ~ R* 6w($
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import com.javaeye.common.util.PaginationSupport; |Y])|`_'G
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public abstract class AbstractManager extends <"\K|2Sg
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HibernateDaoSupport { Qe4
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privateboolean cacheQueries = false; -|3U0:'m
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privateString queryCacheRegion; Aa1 |{^$:L
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publicvoid setCacheQueries(boolean v =u|D$
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cacheQueries){ H?aB8=)
this.cacheQueries = cacheQueries; ;bA9(:?
} 2'x_zMV
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publicvoid setQueryCacheRegion(String A2+t`[w
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queryCacheRegion){ r[?rwc^
this.queryCacheRegion =
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queryCacheRegion; NuP@eeF>,
} 8l}|.Q#--
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publicvoid save(finalObject entity){ ,O-lDzcw
getHibernateTemplate().save(entity); $ &^
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} ) Z^(+
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publicvoid persist(finalObject entity){ D{8V^%{
getHibernateTemplate().save(entity); =_wgKXBFa
} f/=0
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publicvoid update(finalObject entity){ .*zQ\P
getHibernateTemplate().update(entity); Z>D7C?v:(
} A l` ;SWN
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publicvoid delete(finalObject entity){ )q=1<V44d
getHibernateTemplate().delete(entity); UGN. ]#"#
} R4v=i)A~Z
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publicObject load(finalClass entity, ]>AW
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finalSerializable id){ `Y[zF1$kz^
return getHibernateTemplate().load wWm#[f],?
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(entity, id); $]T7Iwk
} gVD!.
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publicObject get(finalClass entity, fDRQ(}
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finalSerializable id){ %v|,-B7Yx
return getHibernateTemplate().get G?"1
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(entity, id); \fKv+
} SKS[Lf
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publicList findAll(finalClass entity){ RM`8P5i]sF
return getHibernateTemplate().find("from 62zlO{ >rJ
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" + entity.getName()); lS,Hr3Lz
} c'(]n]a%
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publicList findByNamedQuery(finalString \Js9U|lY
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namedQuery){ t=pG6U
return getHibernateTemplate #uH1!UQb
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().findByNamedQuery(namedQuery); hyBSS,I
} ; w+A38N$J
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publicList findByNamedQuery(finalString query, j`#|z9`(pB
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finalObject parameter){ NH?s
return getHibernateTemplate x##Iv|$
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().findByNamedQuery(query, parameter); `"bm Hs7
} ogPfz/ hw
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publicList findByNamedQuery(finalString query, G>!"XK:fB
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finalObject[] parameters){ ^6`R:SV4Gx
return getHibernateTemplate ;m&f Vp
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().findByNamedQuery(query, parameters); A1Zu^_y'
} I,#U
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publicList find(finalString query){ Zc"]Cv(
return getHibernateTemplate().find G%6wk=IH
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(query); >!oN+8[~
} > W0hrt?b
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publicList find(finalString query, finalObject 57oY]NT?
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parameter){ ngNg1zV/q
return getHibernateTemplate().find \/,SH?>4x
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(query, parameter); adxJA}K}
} bEy%S"\<
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public PaginationSupport findPageByCriteria Cf+O7Y`^
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(final DetachedCriteria detachedCriteria){ -&HN h\
return findPageByCriteria ;lK2]
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); @ce4sSo
} 0W>O,%z&P#
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public PaginationSupport findPageByCriteria hQkmB|];5
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(final DetachedCriteria detachedCriteria, finalint *JDc1$H0
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startIndex){ omY?`(=
return findPageByCriteria hMD yE.X-
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(detachedCriteria, PaginationSupport.PAGESIZE, k4`v(au^
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startIndex); qNvKlwR9;k
} a'A0CQ
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public PaginationSupport findPageByCriteria x~(Ul\EX
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(final DetachedCriteria detachedCriteria, finalint IMrB!bor
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pageSize, 0m@S+$v
finalint startIndex){ f.u{;W
return(PaginationSupport) ,%:`Ll
t]$
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getHibernateTemplate().execute(new HibernateCallback(){ l@GpVdrv
publicObject doInHibernate q6,xsO,+
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(Session session)throws HibernateException { %tu{`PN<
Criteria criteria = #VrT)po+
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detachedCriteria.getExecutableCriteria(session); pjoI};
int totalCount = 1k hwwoo
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((Integer) criteria.setProjection(Projections.rowCount +6>Pp[%
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()).uniqueResult()).intValue(); |W::\yu6
criteria.setProjection 2L\h+)
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(null); ?W|POk}
List items =
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criteria.setFirstResult(startIndex).setMaxResults [F>zM
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(pageSize).list(); kP| !!N
PaginationSupport ps = L Y M`
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new PaginationSupport(items, totalCount, pageSize, ]:f1r8<3p
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startIndex); R52!pB0[
return ps; Eod2vr=Q
} oL~Yrb%R
}, true); 6suc0
} jG/kT5S
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public List findAllByCriteria(final 00Rk %QV
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DetachedCriteria detachedCriteria){ vXf#gX!Y
return(List) getHibernateTemplate fHgfI@{=j
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().execute(new HibernateCallback(){ _l Jj 6=
publicObject doInHibernate &wjOb
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(Session session)throws HibernateException { xq]&XlA:ug
Criteria criteria = ZBYmAD
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detachedCriteria.getExecutableCriteria(session); |)lo<}{
return criteria.list(); Tu"yoF
} m760K*:i\
}, true); PF+`3
} q8p 'bibY
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public int getCountByCriteria(final J)(pGS@
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DetachedCriteria detachedCriteria){ Fl
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Integer count = (Integer) ?oF@q :W
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getHibernateTemplate().execute(new HibernateCallback(){ (thzWr6;
publicObject doInHibernate gi`ZFq@
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(Session session)throws HibernateException { JAn3
Criteria criteria = 6?`py}:
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detachedCriteria.getExecutableCriteria(session); (kSkbwu
return EUNG&U
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criteria.setProjection(Projections.rowCount N0XGW_f
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()).uniqueResult(); >!wwXhH(
} $L&*0$[]Q
}, true); +yTL
return count.intValue(); .c',?[S/vH
} ePF9Vzq
} f"-?%I*'
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用户在web层构造查询条件detachedCriteria,和可选的 ;m\(fW*ii
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 <;Xj4
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PaginationSupport的实例ps。 0lEIj/u
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ps.getItems()得到已分页好的结果集 9K&b1O@Aj
ps.getIndexes()得到分页索引的数组 yb]a p
ps.getTotalCount()得到总结果数 jjwY{jV
ps.getStartIndex()当前分页索引 fu|I(^NV
ps.getNextIndex()下一页索引 e]5QqM7
ps.getPreviousIndex()上一页索引 e5AiIVlv
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 .z9JoQ
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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 Axcm~!uf
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一下代码重构了。 R` N-^x
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我把原本我的做法也提供出来供大家讨论吧: #\"5:.H Oz
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首先,为了实现分页查询,我封装了一个Page类: ?>w%Lg{L}
java代码: Ms$kL'/
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/*Created on 2005-4-14*/ mO\6B7V!
package org.flyware.util.page; avT>0b:
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/** {:? -)Xq
* @author Joa =A,i9Z&
* _E1:3N|
*/ .|rpj&>g
publicclass Page { LsLsSV
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/** imply if the page has previous page */ VfQSfNsi
privateboolean hasPrePage; /2YI!U@A
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/** imply if the page has next page */ b,!h[
privateboolean hasNextPage; T+gqu
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* %MY. #
/** the number of every page */ GB{%4)%6
privateint everyPage; _|#)tWy}
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/** the total page number */ Z*oGVr
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privateint totalPage; tewC *%3V
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/** the number of current page */ +4@EJRC
privateint currentPage; gXF.e.uU
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/** the begin index of the records by the current No h*1u*
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query */ ^c/.D*J[I
privateint beginIndex; [rf.P'p%
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/** The default constructor */ $cYh X^YG.
public Page(){ :V >Z|?[*H
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} f>Ij:b`Z2
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/** construct the page by everyPage oo/#]a
* @param everyPage aiz_6@Qfz*
* */ []'BrG)!
public Page(int everyPage){ -`A6K!W&~p
this.everyPage = everyPage; vQ
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} pvcD
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/** The whole constructor */ qi$6y?
public Page(boolean hasPrePage, boolean hasNextPage, 2r\f!m'
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int everyPage, int totalPage, KecR jon ~
int currentPage, int beginIndex){ 8*lVO2
this.hasPrePage = hasPrePage; 'w&,3@Z
this.hasNextPage = hasNextPage; P0|V1,)
this.everyPage = everyPage; c!j$-Ovm
this.totalPage = totalPage; hX<0{pXM4
this.currentPage = currentPage; S\mh{#Lpk
this.beginIndex = beginIndex; \|Us/_h
} CGPPo;RjK
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/** ^
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* @return =%p0rz|b
* Returns the beginIndex. s:6H^DQ"C
*/ <&Y7Q[
publicint getBeginIndex(){ 8I`>tY
return beginIndex; Lxs
} 6>zO"9
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/** PjDYdT[
* @param beginIndex h>q&X4-
* The beginIndex to set. }c$Zlb
*/ XZ}]H_, n
publicvoid setBeginIndex(int beginIndex){ &h')snp:#
this.beginIndex = beginIndex; >q"mI6F
} IrM Ws86;
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/** /0@'8f\I
* @return 0]fzjiaGt
* Returns the currentPage. >]s|'HTxF
*/ /n&w|b%
publicint getCurrentPage(){ G
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return currentPage; up#W"`"
} zXIVHC,"{
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/** bU7n1pzW,o
* @param currentPage ol[
* The currentPage to set. H)ud?vB6
*/ MQ7N8 @!t
publicvoid setCurrentPage(int currentPage){ ,eW K~ pa
this.currentPage = currentPage; JN,4#,
} ^cn%]X#.
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/** =#
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* @return JgEPzHgx
* Returns the everyPage. ">@]{e*
*/ `O5wM\Z
publicint getEveryPage(){ @l41'?m
return everyPage; $qV, z
} V9mqJRFJ:
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/** \QGh@AQp"
* @param everyPage Y{ijSOl3
* The everyPage to set. 49W@?:b
*/ yb\T<*
publicvoid setEveryPage(int everyPage){ +`}QIp0
this.everyPage = everyPage; ibAZ=RD
} *eK\W00
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/** MAb*4e#
* @return x-1RmL_%
* Returns the hasNextPage. qr~P$
*/ Jz<-B
publicboolean getHasNextPage(){ G)t_;iNL|
return hasNextPage; o<cg9
} 1DLAfsLlj
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/** *t=8^q(K[
* @param hasNextPage mE\sD<b
* The hasNextPage to set. D<U^FT
*/ C>wOoXjt
publicvoid setHasNextPage(boolean hasNextPage){ 4z%::?
this.hasNextPage = hasNextPage; l1HMH?0|
} jlXzfDT
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/** Td(eNe_4T
* @return X$BN&DD
* Returns the hasPrePage. fqpbsM;M]
*/ 2@~.FBby7@
publicboolean getHasPrePage(){ !LJE o>D
return hasPrePage; ua%@Ay1|
} ,Pi!%an w
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/** IyK^` y
* @param hasPrePage 6Ft?9
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* The hasPrePage to set. 0gTv:1F/
*/ Rxb?SBa
publicvoid setHasPrePage(boolean hasPrePage){ 3u[m? Vw
this.hasPrePage = hasPrePage; lDsT?yHS`Z
} nQ*9E|Vx
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/** fJ<I|ZZ
* @return Returns the totalPage. iq1HA.X(
* .bYZkO:oy
*/ /|s~X@%K
publicint getTotalPage(){ 27J!oin$
return totalPage; N>
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} A#7/,1h\
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/** ahICx{hK
* @param totalPage ^#( B4l!
* The totalPage to set. ty ESDp%
*/ r+:]lO
publicvoid setTotalPage(int totalPage){ C GN=kQ
this.totalPage = totalPage; f |%II,!3
} $|"Y|3&X
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} Ms=5*_J2Jk
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上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 r{cmw`WA/P
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个PageUtil,负责对Page对象进行构造: )fy-]Ky
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java代码: r{ >`"
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/*Created on 2005-4-14*/ (n{x"rLy/
package org.flyware.util.page; z`}z7e'>
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import org.apache.commons.logging.Log; &zR\Rmpt
import org.apache.commons.logging.LogFactory; _ sqj~|K
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/** +$}3=n34)
* @author Joa 9epMw-)k
* cslZ;
*/ y#T.w0*
publicclass PageUtil { r1axC%
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privatestaticfinal Log logger = LogFactory.getLog ='vD4}"j
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(PageUtil.class); Y1Q240
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/** 8$F"!dc _
* Use the origin page to create a new page I1pnF61U
* @param page ,B~5;/|
* @param totalRecords 57wHo[CJ
* @return 4aP 96
*/ $fCKK&Wy
publicstatic Page createPage(Page page, int LD*XNcE
/8#e < p
totalRecords){ T>hrKn.!D:
return createPage(page.getEveryPage(), aPdEEqc\l
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page.getCurrentPage(), totalRecords); ,&~-Sq)~
} Ij>G7Q*d
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/** i/.#`
* the basic page utils not including exception =,b6yV+$D
4^Ss\$*
handler 1=Kt.tuf
* @param everyPage ^Ig QIN
* @param currentPage "T$LJ1E
* @param totalRecords dl.gCiI
* @return page Cag^$nj
*/ w}]BJ<C
publicstatic Page createPage(int everyPage, int 0QP=$X
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currentPage, int totalRecords){ ?edf$-"z/
everyPage = getEveryPage(everyPage); p*j>s\
currentPage = getCurrentPage(currentPage); 0q4PhxR`e
int beginIndex = getBeginIndex(everyPage, 0q28Ulv9
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{
currentPage); &MZ{B/;;H
int totalPage = getTotalPage(everyPage, bf=!\L$
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totalRecords); U!{~L$S
boolean hasNextPage = hasNextPage(currentPage, .-'_At4g
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totalPage); @HzK)%@
boolean hasPrePage = hasPrePage(currentPage); KPVu-{_Fi
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returnnew Page(hasPrePage, hasNextPage, /mA\)TL|]
everyPage, totalPage, +DG-MM%\
currentPage, OMW]9E
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beginIndex); Q<NQ9lX
} 4{Q$^wD+.
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privatestaticint getEveryPage(int everyPage){ *LMzq9n3o
return everyPage == 0 ? 10 : everyPage; {Q>4zepN!
} *8Su:=*b
yEMM@5W)8
privatestaticint getCurrentPage(int currentPage){ F Uz1P
return currentPage == 0 ? 1 : currentPage; YZ]}l%e
} |"PS e~ u
_Ss}dU9
privatestaticint getBeginIndex(int everyPage, int "n{';Q)
TMD\=8Na
currentPage){ ,RDWx
return(currentPage - 1) * everyPage; 9_?<T;]"
} S|xwYaoy%
M@l |n
privatestaticint getTotalPage(int everyPage, int dDSb1TM
}.(DQwC}1k
totalRecords){ z;?ztpa@
int totalPage = 0; CDF;cM"td
,{\Ae"{6
if(totalRecords % everyPage == 0) aS[y\9(**
totalPage = totalRecords / everyPage; '%ByFZzi
else +1I7K|M
totalPage = totalRecords / everyPage + 1 ; "Bv V89
:IU<A G6
return totalPage; Z
t4q=
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} B uso
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\crh`~?>
privatestaticboolean hasPrePage(int currentPage){ j\wZjc-j
return currentPage == 1 ? false : true; p0y|pD
} $tF\7.e@
~3-"1E>Rgy
privatestaticboolean hasNextPage(int currentPage, RX%)@e/@
nGwon8&]]
int totalPage){ U.V/JbXX
return currentPage == totalPage || totalPage == *P5\T4!+d
O8A(OfX
0 ? false : true; (,ik:j
} +=Q:g,kP
\D k >dE&I
=>lX brJ
} ;
wxmSX9
|'&$VzA
,}khu
3Z`"k2k
]%I\FefT
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。 #?+[|RS|
PjX V.gz
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 N34-z|"q
4DDBf j
做法如下: E|>-7k")
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 NV-l9
WO{7/h</
的信息,和一个结果集List: pouXt-%2X
java代码: F+*fim'NK
t9MCT$U
?-%(K^y4r
/*Created on 2005-6-13*/ 3UmkFK<
package com.adt.bo; "wcw`TsK
ji>LBbnHdE
import java.util.List; rW|%eT*/'A
{chZ&8)f
import org.flyware.util.page.Page; ?{}P#sn
=-~))!(
/** {}8C/4iP
* @author Joa q5S_B]|
*/ { `Z~T&}~T
publicclass Result { <"6\\#}VG
)A%* l9\nG
private Page page; IiRQ-,t1
sV-PR]
private List content; 63%V_B|
wsQ],ZE
/** ,C"6@/:l
* The default constructor l5=ih9u
*/ Itv cN
public Result(){ yH]Q;X'
super(); K!qOO
} ]" e'z
JIw?]xa*
/** MRXw)NAw
* The constructor using fields >q&5Z
* T
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* @param page U^|T{g+O
* @param content U}DE9e{/!
*/ %FM26^
public Result(Page page, List content){ ab2Cn|F
this.page = page; -BI!ZsC'
this.content = content; $Zo|ta^
} &*'^uCna
Fbu4GRgJ3
/** Mh2b!B
* @return Returns the content. =H8FV09x}
*/ hu} vYA7ZH
publicList getContent(){ :j .:t
return content; tY]?2u%)
} N>YSXh`W`y
/n(0w`
/** `p9N| V
* @return Returns the page. V sxI
*/ 'I+M*Iy
public Page getPage(){ 4i{Xs5zk
return page; <9
^7r J
} G1w$lc
AaxQBTB
/** kvbW^pl
* @param content T[xIn+w
* The content to set. @VW1^{.do^
*/ (y6q}#<
public void setContent(List content){ 62,dFM7
this.content = content; *xpn-hCp<
} _EP]|DTfr
~Gmt,l!b
/** 82ixv<B
* @param page o6;
* The page to set. )92(C
*/ 4H,c;g=!
publicvoid setPage(Page page){ p`A2^FS)
this.page = page; QD{1?aY
} 4U}J?EB?K
} GTTEg{
OomC%9/=,
l,]%D
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-;781
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2. 编写业务逻辑接口,并实现它(UserManager, d>mZY66P
=bja\r{
UserManagerImpl) svDnw cl
java代码: "OYD9Q''
|>xuH#Q
~+0IFJ `}
/*Created on 2005-7-15*/ #_S]\=N(
package com.adt.service; 2[3t7 C
>itabG-&
import net.sf.hibernate.HibernateException; ps:`rVQ7
13Z,;YW
import org.flyware.util.page.Page; HyWR&0J
'" %0UflJS
import com.adt.bo.Result; <`=Kt[_BQ
VVAc bAGJ
/** HBvyX`-
* @author Joa -Z:x!M[Xr
*/ QN$s%&O
publicinterface UserManager { <'$>&^!^
7]1a3Jk
public Result listUser(Page page)throws !*~QB4\2b
hx;kNcPbI
HibernateException; XC~"T6F
gl`J(
} o$;&q
*
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Spx%`O<
r9N?z2X
Cj4Y, N
java代码: k
Qr
c CDT27@
|5dNJF8;Q
/*Created on 2005-7-15*/ 6Y\TVRR
package com.adt.service.impl; @{fwM;me]P
oz.z>+Q
import java.util.List; bcy
v'?o#_La+
import net.sf.hibernate.HibernateException; 1;<Vr<.
x+za6e_k"
import org.flyware.util.page.Page; yv]|Ce@8A
import org.flyware.util.page.PageUtil; cMT:Ij];
{*hvzS{1d
import com.adt.bo.Result; n!~ $Z/
import com.adt.dao.UserDAO; 8]vut{
import com.adt.exception.ObjectNotFoundException; 4XVwi<)
import com.adt.service.UserManager; 9#hp]0S6
y0T#Qq
/** 65O 8?I
* @author Joa fUY05OMZ
*/ 1Dhe!
n#
publicclass UserManagerImpl implements UserManager { VK*`&D<P
ke;=Vg|
private UserDAO userDAO; Z:AB(c
KFO
K%vbM
/** <Fx%P:d
* @param userDAO The userDAO to set. W<#!H e
*/ <XDnAv0t
publicvoid setUserDAO(UserDAO userDAO){ :NWIUN
this.userDAO = userDAO; gfIS
} Z&iW1
YuVlD/
/* (non-Javadoc) s#a`e]#?
* @see com.adt.service.UserManager#listUser wzxV)1jT
#W8?E_iu
(org.flyware.util.page.Page) }AB_i'C0
*/ KGc.YUoE
public Result listUser(Page page)throws J
%A=
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HibernateException, ObjectNotFoundException { %{ rb,6
int totalRecords = userDAO.getUserCount(); zGz}.-F
if(totalRecords == 0) 5RWqHPw+
throw new ObjectNotFoundException cH5
sm{0o$\Z
("userNotExist"); A_E2v{*n
page = PageUtil.createPage(page, totalRecords); nu1XT 1q1
List users = userDAO.getUserByPage(page); Xr8fmJtg'
returnnew Result(page, users); 3J
5,V
} S},Cz
0nD?X+ u
} >\:GFD{z
xq,ql@7
QP50.P5g
dwUDhQt3Q
+UX~'t_'v
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 <+
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询,接下来编写UserDAO的代码: v%2Dz
3. UserDAO 和 UserDAOImpl: j-**\.4a~
java代码: oidK_mU9q
_e>N3fT
@VIY=qh
/*Created on 2005-7-15*/ wY%t# [T3
package com.adt.dao; t@MUNW`Q
0`WFuFi^o
import java.util.List; EHhc2^e
j8 2w
3
import org.flyware.util.page.Page; U" 3L
JtMl/h
import net.sf.hibernate.HibernateException; 1##@'L|u
mP6}$D
/** 5+oY c-
* @author Joa 8:S+*J[gSn
*/ {t!
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publicinterface UserDAO extends BaseDAO { V;CRs\aYf
"mE/t (
publicList getUserByName(String name)throws i!UT =
E24}?t^|
HibernateException; F[jqJzCz
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publicint getUserCount()throws HibernateException; IOC$jab@
`5Z'8^
publicList getUserByPage(Page page)throws V?.=_T<
DxN\ H"
HibernateException; cc`u{F9
y1}2hT0,
} +IbV
4B[pQlg
(
[a$Z2m
A ep](je
OMo /a%`
java代码: |k]]dP|:'
WwWOic2
os;94yd)
/*Created on 2005-7-15*/ )[UYCx'
package com.adt.dao.impl; -W@nc
QL}
K+ M\E[1W
import java.util.List; N\. g+ W
"'Gq4<&y
import org.flyware.util.page.Page; KTmwkZcfYD
q)C
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import net.sf.hibernate.HibernateException; gn.)_
import net.sf.hibernate.Query; 9$9aBW
"x;FE<I
import com.adt.dao.UserDAO; ~(tt.l#
Uy|!f]"?
/** $'d,X@}8
* @author Joa yk4py0xVl
*/
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public class UserDAOImpl extends BaseDAOHibernateImpl Hl(W'>*oL
*w^!\
implements UserDAO { seAEv0YWz
@C[p? ak
/* (non-Javadoc) #"TYk@whWf
* @see com.adt.dao.UserDAO#getUserByName jZmL7
V
e&ZH 1^O
(java.lang.String) n.NWS/v_{
*/ r7}KV| M
publicList getUserByName(String name)throws GJE+sqMX1
e8:O2!HW
HibernateException { 2{l|<'
String querySentence = "FROM user in class W;!V_-:
:iE`=( o
com.adt.po.User WHERE user.name=:name"; T 8]*bw
Query query = getSession().createQuery kt_O=
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(querySentence); nI(w7qhub
query.setParameter("name", name); "^{Hta
return query.list(); >Q"3dw
} IS[q'Cv*
"B"ql-K
/* (non-Javadoc) g%^/^<ei
* @see com.adt.dao.UserDAO#getUserCount() NgsEEPu?
*/ lF46W
publicint getUserCount()throws HibernateException { [z7]@v6b
int count = 0; -R];tpddR5
String querySentence = "SELECT count(*) FROM G i(
4T$jY}U
user in class com.adt.po.User"; 6q0)/|,@
Query query = getSession().createQuery H0lW gJmi|
OU]"uV<(
(querySentence); >bhF{*t#;y
count = ((Integer)query.iterate().next g~9rt_OV
:~s*yznf
()).intValue(); mxJe\[I
return count; &ns??:\+T
} 9X#]Lg?b
[;-;{
*{G
/* (non-Javadoc) 5__B
M5|
* @see com.adt.dao.UserDAO#getUserByPage V}2[chbl
Lq6nmjL
(org.flyware.util.page.Page) ~SA>$
*/ &"Cy&[
publicList getUserByPage(Page page)throws x2b
t^!t.
Ag(JSVY
HibernateException { -<T>paE9
String querySentence = "FROM user in class +Qzl-eN/+
3FO-9H
com.adt.po.User"; ,|zwY~lt5
Query query = getSession().createQuery 4pcIH5)z
u~'_Uqp
(querySentence); ,}>b\(Lk
query.setFirstResult(page.getBeginIndex()) \>j@!W
.setMaxResults(page.getEveryPage()); {m,LpI0wG
return query.list(); >8vq`,e
} CSWA/#&8>
ZN'B@E=p
} wF6a*b@v
#X{lV]Z
[(8s\>T
<5FGL96
CL(D&8v8~
至此,一个完整的分页程序完成。前台的只需要调用 C\bJ_vl;'
mB
bGj3u;
userManager.listUser(page)即可得到一个Page对象和结果集对象 mL;oR4{
,]9p&xu
的综合体,而传入的参数page对象则可以由前台传入,如果用 o:as}7/^
mmNn,>AO!
webwork,甚至可以直接在配置文件中指定。 pA@R,O>zr
rT4q x2 u
下面给出一个webwork调用示例: 1[a#blL6W
java代码: *9F{+)A
awQB0ow'$P
28}L.>5k
/*Created on 2005-6-17*/ w#L`|cYCm
package com.adt.action.user; Fy6Lz.baB
(Nf!E[}Z
import java.util.List; "1DlusmCCB
r=RiuxxTq
import org.apache.commons.logging.Log; Rp_ }_hL0
import org.apache.commons.logging.LogFactory; 0Uk;&a0s
import org.flyware.util.page.Page; 8f'r_,"
M4d4b
import com.adt.bo.Result; :V)=/mR
import com.adt.service.UserService; ):L0{W{
import com.opensymphony.xwork.Action; (J(SwL|
nU2w\(3|
/** 2j{T8F\]
* @author Joa }^odUIj
*/ ^Vc(oa&;
publicclass ListUser implementsAction{ [8WG
?xQm_
91X^
privatestaticfinal Log logger = LogFactory.getLog 9:E.Iy
4a.8n!sys
(ListUser.class); \y7\RV>>3b
69odE+-X.
private UserService userService; 7<?Aou
zrC1/%T
private Page page; 2,h]Y=.s
u+pZ<Bb
privateList users; ,x[~|J!
ob[G3rfd@Z
/* 5'wFZ=>vMt
* (non-Javadoc) ZNDjk
* QbWeQ[V{
* @see com.opensymphony.xwork.Action#execute() u*7>0o|H:
*/ i>pUTT
_[
publicString execute()throwsException{ mJVru0
Result result = userService.listUser(page); ]qk`Yi
page = result.getPage(); Q$yQ^ mG
users = result.getContent(); Qgo|\=
return SUCCESS; X#MC|Fzy@
} uxW<Eh4H*
)@.0ai
/** QT(]S>--n
* @return Returns the page. !]z4'* )W
*/ O&dh<
public Page getPage(){ W#x~x| (c
return page; ?,eq86-M
} [F,s=,S'M
sA,2gbW
/** Z/e[$xT <
* @return Returns the users. `TDS4Y
*/ R]S!PSoL
publicList getUsers(){ -x>2Wb~%
return users; lt0byn$vz
} LdX'V]ITh
d}^hZ8k|
/** nc#} \
* @param page {-)I2GJav
* The page to set. FJ|JXH*
*/ Yjx4H
publicvoid setPage(Page page){ xl(R|D))
this.page = page; gI+dyoh
} `] Zil8n
*!}bU`
/** Xh*NuHH
* @param users ;xu&%n[6@
* The users to set. Uee$5a>(
*/ zhI"++
publicvoid setUsers(List users){ ~8lB#NuN
this.users = users; m{rsjdnA
} #\3X;{
ev5m(wR
/** 0(^N
* @param userService N8{
8 a
* The userService to set. mP./e8
*/ m*>gG{3;
publicvoid setUserService(UserService userService){ }FkF1?C
this.userService = userService; :-T[)Q+-3
} +,4u1`c|$
} nS^,Sq\Ak
QM=Y}
'#612iZo
A+"'8%o9}
'u:J
"
上面的代码似乎看不出什么地方设置了page的相关初值,事实上, 8+&Da
D[K!xq
可以通过配置文件来进行配置,例如,我想每页显示10条记录,那 edfb7prfTl
\~>7n'd ]
么只需要: &^F'ME
java代码: %/%TR@/
%07vH&<C.
2-@z-XKn
<?xml version="1.0"?> Q\*zF,ek
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork :io[9B [
?;
tz
1.0//EN" "http://www.opensymphony.com/xwork/xwork- C ?aa)H
rCdTn+O2
1.0.dtd"> +)*oPSQ5
sl G%o5|m
<xwork> cg}lF9;d
##yH*{/&
<package name="user" extends="webwork- a )M3t
Ak@y"!wnM
interceptors"> BBRZlx
e3%dNa
<!-- The default interceptor stack name 2;ac&j1
`_<O_
--> 8}|!p>
<default-interceptor-ref 6JE_rAab
:}ZY*ind
name="myDefaultWebStack"/> /k=krAz.
y7.oy"
<action name="listUser" ,TQ;DxB}=E
C=P}@| K
class="com.adt.action.user.ListUser"> [LKzH!
<param gq&jNj7V
}_9yemP
name="page.everyPage">10</param> vH>s2\V"
<result '],G!U(
;b0;66C8|
name="success">/user/user_list.jsp</result> y:R+; 91
</action> =nG>aAG
7Q #A
</package> k,jcLX.
ePiZHqIsv/
</xwork> 'OsRQ)E
'2ACZcjDSv
18ON`j
_*u$U
p1
mY!&e(
!~ZAm3GwL
这样就可以通过配置文件和OGNL的共同作用来对page对象设置初值 3U[:N
&Jb
|
=tGrHL
了。并可以通过随意修改配置文件来修改每页需要显示的记录数。 j%fi*2uX
}syU(];s
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 3ZX#6*(}2
;~Q`TWC
N=c{@h
<y,c.\c!
;Bne=vjQp
我写的一个用于分页的类,用了泛型了,hoho {R5_=MG
5_4=(?<
java代码: eVGW4b
Poxoc-s
F|?}r3{aJ
package com.intokr.util; g ~>nT>6
P+Sgbtc
import java.util.List; w9CX5Fg
xgZ<.r
/** )Xice=x9
* 用于分页的类<br> :Oi}X7\
* 可以用于传递查询的结果也可以用于传送查询的参数<br> a*!9RQ
* 9Q&]5|x
* @version 0.01 6'jgjWEe3&
* @author cheng %H=^U8WB
*/ M8f[ ck
public class Paginator<E> { \};
4rm}V
privateint count = 0; // 总记录数 t7,** $ST
privateint p = 1; // 页编号 !s[gv1
privateint num = 20; // 每页的记录数 8,]wOxwqi
privateList<E> results = null; // 结果 FOS*X
/7K7o8g
/** Bh()?{q
* 结果总数 G Cp90
*/ d"}lh:L9
publicint getCount(){ X9ec*x
return count; 5YQJNP
} lYy:A%yDT
@ [j%V ynf
publicvoid setCount(int count){ C0H@
this.count = count;
{5JYu
} ){4$oXQ
jN!sLW
/** ``Rg0o
* 本结果所在的页码,从1开始 ^2"w5F
* hGo/Ve+@
* @return Returns the pageNo. SQDc%I>b
*/ ,sltB3f
publicint getP(){ P$"s*otr
return p; &IkHP/
} .Iv`B:4
$QaEU="Z
/** )?k~E=&o