Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 86y)+h`
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 D;*P'%_Z
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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 Po_y78ZD
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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 Y- esD'MD
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分页支持类: 2)cq!Zv
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java代码: #2{H!jr
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package com.javaeye.common.util; sbqAjm}
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import java.util.List; JB[n]|
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publicclass PaginationSupport { F`))qCgg]
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publicfinalstaticint PAGESIZE = 30; \%[sv@P9s
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privateint pageSize = PAGESIZE; /zV&ebN]
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privateList items; {^(h*zxn
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privateint totalCount; 3}hJ`xQ
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privateint[] indexes = newint[0]; GP<PU
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privateint startIndex = 0; b%A+k"d
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public PaginationSupport(List items, int (t[sSl
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totalCount){ |YEq<wbQ
setPageSize(PAGESIZE); xNAX)v3Z
setTotalCount(totalCount); we?#
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setItems(items); ,v\^efc:%
setStartIndex(0); |f67aN
} x#)CH}J
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public PaginationSupport(List items, int skeH~-`M@
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totalCount, int startIndex){ I.dS-)Y
setPageSize(PAGESIZE); {$AwG#kt
setTotalCount(totalCount);
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setItems(items); 5TynAiSD_>
setStartIndex(startIndex); 1|bg;X9+
} <b>g^ `}?D
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public PaginationSupport(List items, int {#U3A_y
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totalCount, int pageSize, int startIndex){ "WF@T
setPageSize(pageSize); T@H<Fm_
setTotalCount(totalCount); 6> DmcG:.
setItems(items); 2UbTKN
setStartIndex(startIndex); M1HGXdN* B
} #EG$HX]
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publicList getItems(){ y\?NB:=%
return items; z*,J0)<Q
} A r,fmq
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publicvoid setItems(List items){ , ;$SRQ.
this.items = items; m:-=K
} H3#rFO"C*
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publicint getPageSize(){ [ikW3 '99,
return pageSize; yt+d
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} [x[nTIg
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publicvoid setPageSize(int pageSize){ $Cnv]1%
this.pageSize = pageSize; X+7@8)1(
} Qo\+FkhYq
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publicint getTotalCount(){ rK~Obv
return totalCount; IeN~E'~
} )=TS)C4
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publicvoid setTotalCount(int totalCount){ vX;~m7+
if(totalCount > 0){ }Gf9.ACQ
this.totalCount = totalCount; 89Ch'D
int count = totalCount / ioT+,li
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pageSize; CbW>yr
if(totalCount % pageSize > 0) uz;zmK
count++; X+KQ%Efo
indexes = newint[count]; v{8W+
for(int i = 0; i < count; i++){ NTV@,
indexes = pageSize * 01w}8a(
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} pq +~|
}else{ >(He,o@M
this.totalCount = 0; i87+9X
} +'V ,z
} <wTD}.n
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publicint[] getIndexes(){ wOV}<.W
return indexes; k#"}oI{<
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} :{=2ih-}
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publicvoid setIndexes(int[] indexes){
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this.indexes = indexes; #`qP7E w
} \Xpq=2`
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publicint getStartIndex(){ $:IEp V{
return startIndex; f#3!Q!C^
} m{?uR.O
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publicvoid setStartIndex(int startIndex){ yL#2|t(
if(totalCount <= 0) kWZ/O
this.startIndex = 0; pxV@ fH+`
elseif(startIndex >= totalCount) Z(c2F]
this.startIndex = indexes ~{$5JIpCm
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[indexes.length - 1]; ^oXLk&d
elseif(startIndex < 0) oGKk2oP
this.startIndex = 0; L(`Rf0smt
else{ Dssecc'
this.startIndex = indexes Yq0j w&v
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[startIndex / pageSize]; dkAY%z two
} _i pY;
} C^fUhLVSZ^
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publicint getNextIndex(){ 8m*uT< 5D
int nextIndex = getStartIndex() + ->*'Y;t4
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pageSize; 8/T,.<5
if(nextIndex >= totalCount) l'FNp
return getStartIndex(); M]uO%2
else I%tJLdL
return nextIndex; :>o2UH
} !8}x6
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publicint getPreviousIndex(){ E3d# T
int previousIndex = getStartIndex() - AfX lV-v
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pageSize; &uLC{Ik}
if(previousIndex < 0) 7thB1cOJ
return0; 2[~|6@n
else \{{i:&] H
return previousIndex; 2>'/!/+R
} p -wEPC0
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} 0Q5fX}
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抽象业务类 +&qj`hA-b
java代码: o 4cqLMu
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/** jQi)pVT^
* Created on 2005-7-12 woyeKOr
*/ uS&NRf9A
package com.javaeye.common.business; hM~zO1XW
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import java.io.Serializable; 3ox
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import java.util.List; jCxg)D7W
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import org.hibernate.Criteria; uBA84r%{QQ
import org.hibernate.HibernateException; f+>g_Q
import org.hibernate.Session; MtXTh*4
import org.hibernate.criterion.DetachedCriteria; xyPz_9
import org.hibernate.criterion.Projections; C?fa-i0l^
import b5Vn _;V*
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org.springframework.orm.hibernate3.HibernateCallback; D>m!R[!o
import qcR"i+b
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org.springframework.orm.hibernate3.support.HibernateDaoS 5/C#*%EH'
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upport; ?)mM]2%%
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import com.javaeye.common.util.PaginationSupport; :}3;z'2]l
@ !m+s~~]h
public abstract class AbstractManager extends x$;kA}gy
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HibernateDaoSupport { $i.)1.x
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privateboolean cacheQueries = false; KSB{Z TE
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privateString queryCacheRegion;
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publicvoid setCacheQueries(boolean pqnZ:'V
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cacheQueries){ 0zr Zrl
this.cacheQueries = cacheQueries; 2-x#|9
} 0pl |
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publicvoid setQueryCacheRegion(String yVl?gGgh
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queryCacheRegion){ J)"g`)\2 +
this.queryCacheRegion = 7^*[ XH
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queryCacheRegion; Kfk/pYMDq
} $*z>t*{7
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publicvoid save(finalObject entity){ j/PNi@
getHibernateTemplate().save(entity); Avr2MaY{h
} ZI NqIfc
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publicvoid persist(finalObject entity){ =#K$b *#
getHibernateTemplate().save(entity); `2.2; Vk
} oRQJ YH
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publicvoid update(finalObject entity){ KL4vr|i,
getHibernateTemplate().update(entity); t8\XOj
} 8oVQ:' 6
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publicvoid delete(finalObject entity){ ^L +@oS
getHibernateTemplate().delete(entity); y;1l].L
} 8e*1L:oB!
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publicObject load(finalClass entity, d/!R;,^
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finalSerializable id){ 'v:%} qMv
return getHibernateTemplate().load 9e>Dqlv
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(entity, id); mOE%:xq9-
} Ed +"F{!eQ
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publicObject get(finalClass entity, b%"Lwqdr7
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finalSerializable id){ bL"!z"NA
return getHibernateTemplate().get QGpAG#M9?
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(entity, id); mZ^ev;
} L6E8A?>5rD
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publicList findAll(finalClass entity){ C=uYX"
return getHibernateTemplate().find("from UthH
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" + entity.getName()); f!n0kXVu6U
} '&n4W7
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publicList findByNamedQuery(finalString Ln
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namedQuery){ F,'rW:{HMt
return getHibernateTemplate 1@L|EFa
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().findByNamedQuery(namedQuery); j!;y!g
} :^[HDI-[2
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publicList findByNamedQuery(finalString query, vk]vtjf&%
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finalObject parameter){ i6y$P6s
return getHibernateTemplate @ky<5r*JU(
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().findByNamedQuery(query, parameter); Q>[Xm)jr:
} \WN,.
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publicList findByNamedQuery(finalString query, QFYO_$1Y)
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finalObject[] parameters){ 1YxG<K]
return getHibernateTemplate {} gr\
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().findByNamedQuery(query, parameters); 1*o=I-nOa
} l=.h]]`;
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publicList find(finalString query){ >*FH JCe
return getHibernateTemplate().find XwNJHOaF
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(query); 4T<4Rb[
} JX! @j3
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publicList find(finalString query, finalObject O<EFm}Ae
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parameter){ WXzSf.8p|
return getHibernateTemplate().find K6s%=.Zi(
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(query, parameter); 0`D`
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} ZgD%*bH*B
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public PaginationSupport findPageByCriteria ~?#B(t
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(final DetachedCriteria detachedCriteria){ bxrT[]
return findPageByCriteria N(W;\>P
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); ~Y.I;EPKt
} vz1yH%~E
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public PaginationSupport findPageByCriteria `\vqDWh8-
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(final DetachedCriteria detachedCriteria, finalint vdt ":
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startIndex){ XVwJr""+
return findPageByCriteria "ytPS~
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(detachedCriteria, PaginationSupport.PAGESIZE, _hz}I>G@B
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startIndex); 6 J
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} &uMx*TTY
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public PaginationSupport findPageByCriteria iXsX@ S^F
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(final DetachedCriteria detachedCriteria, finalint bCbp JZ
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pageSize, jr`;H
finalint startIndex){ U-mZO7y!
return(PaginationSupport) -\dcs?
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getHibernateTemplate().execute(new HibernateCallback(){ G9
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publicObject doInHibernate (.Th?p%>7
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(Session session)throws HibernateException { L)qDtXd4
Criteria criteria = $]`rWSYtv`
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detachedCriteria.getExecutableCriteria(session); c`E0sgp
int totalCount = YQ7\99tj
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((Integer) criteria.setProjection(Projections.rowCount 99G'`NO
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()).uniqueResult()).intValue(); LjEG1$F>
criteria.setProjection , R;k>'.
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(null); 9(AY7]6
List items = 92 oUQ EK
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criteria.setFirstResult(startIndex).setMaxResults =euMOs
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(pageSize).list(); 6a!b20IZh
PaginationSupport ps = V<&^zIJUR
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new PaginationSupport(items, totalCount, pageSize, \MU-D,@
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startIndex); dMlJ2\]u
return ps; &)ED||r,
} &ra2(S45
}, true); F>lM[Lu#
} :6[G;F7s
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public List findAllByCriteria(final !+V."*]l
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DetachedCriteria detachedCriteria){ !(8)'<t9
return(List) getHibernateTemplate IDK~
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().execute(new HibernateCallback(){ $No^\.mV
publicObject doInHibernate _fM=J+
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(Session session)throws HibernateException { UY}EW`$#m
Criteria criteria = VYw<8AEFY
k((kx:
detachedCriteria.getExecutableCriteria(session); 0 H0U%x8
return criteria.list(); i*jnC>
} '(fzznRH
}, true); "%rzL.</
} m88(f2Ch
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public int getCountByCriteria(final VoC|z Rd_
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DetachedCriteria detachedCriteria){ ZU68\cL
Integer count = (Integer) 8O| w(z
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getHibernateTemplate().execute(new HibernateCallback(){ 9l<}`/@}W
publicObject doInHibernate k!0vpps
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(Session session)throws HibernateException { ;;}}uW=
Criteria criteria = cyH=LjgJf
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detachedCriteria.getExecutableCriteria(session); ql I1<Jx
return pqDlg
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criteria.setProjection(Projections.rowCount :/\KVz'fw}
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()).uniqueResult(); j*_>/gi
} qoAJcr2uN
}, true); U]PsL3:
return count.intValue(); kIJ=]wU|v
} WiqkC#N
} -?L3"rxAP
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用户在web层构造查询条件detachedCriteria,和可选的 @g]>D
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 $VJE&b
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PaginationSupport的实例ps。 J?/NJ-F
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ps.getItems()得到已分页好的结果集 c?}{>ig/)
ps.getIndexes()得到分页索引的数组 i;<K)5Z
ps.getTotalCount()得到总结果数 0~Iq9}{*P
ps.getStartIndex()当前分页索引 G7k.YtW
ps.getNextIndex()下一页索引 bW2Msv/H
ps.getPreviousIndex()上一页索引 :a*F>S!
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 %:.IG.`d
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,尤其是上面的示例代码,让我着实觉得该对我原来的分页查询做 g>n1mK|
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一下代码重构了。 >K
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我把原本我的做法也提供出来供大家讨论吧: ]D@y""{--s
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首先,为了实现分页查询,我封装了一个Page类: ?MD\\gN
java代码: tg;AF<VI
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/*Created on 2005-4-14*/ y<^hM6S?Z
package org.flyware.util.page; W:1GY#Pe
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/** ~-BIUZ;
* @author Joa r1zuc:W1
* x?2y^3<5
*/ (P 9$Ei0fv
publicclass Page { 2l}3L
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/** imply if the page has previous page */ $Hal]
privateboolean hasPrePage; 24I~{Qy
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/** imply if the page has next page */ "FXT8Qxg
privateboolean hasNextPage; '_%`0p1
k7=mxXF
/** the number of every page */ 3M[5_OK
privateint everyPage; rlSflcK\\(
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/** the total page number */ ~c|{PZ9U
privateint totalPage; AUwIF/>F(]
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/** the number of current page */ 4Dv42fO
privateint currentPage; p}
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a WMEo`O%
/** the begin index of the records by the current 3k* U/*
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query */ \"Aw
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privateint beginIndex; 3t$)saQR
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/** The default constructor */ ("_tML 8/p
public Page(){ r8vF I6J
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} wIK&EGQ
[ FNA:
/** construct the page by everyPage [(/IV+
* @param everyPage Ng1uJa[k!d
* */ XkuZ2(
public Page(int everyPage){ yWZ%|K~$
this.everyPage = everyPage; qb$f ,E[
} j~`rc2n%
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/** The whole constructor */ \bumB<w(]
public Page(boolean hasPrePage, boolean hasNextPage, Q~G>=J9
@(s"5i.`)
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int everyPage, int totalPage, UU2=W
int currentPage, int beginIndex){ 5E}~iC&
this.hasPrePage = hasPrePage; a*nx2d
this.hasNextPage = hasNextPage; 2z[A&s_
this.everyPage = everyPage; r$z0C&5
this.totalPage = totalPage; i>L>3]SRr{
this.currentPage = currentPage; VD- 2{em
this.beginIndex = beginIndex; /]"2;e-s+
} y
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/** *8j2iu-|
* @return P]||Xbbp
* Returns the beginIndex.
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*/ |\S p IFH1
publicint getBeginIndex(){ f
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return beginIndex; jwZBWt )5
} w65D;9/;
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/**
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* @param beginIndex aC=D_JJ\
* The beginIndex to set. ) ]3(ue
*/ 5<KY}
publicvoid setBeginIndex(int beginIndex){ rg{|/ ;imT
this.beginIndex = beginIndex; |HMpVT-;j
} Z4@GcdZ
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/** fS(IN~
* @return Ye) F{WqZ#
* Returns the currentPage. B&RgUIrFoY
*/ uQlQ%n%
publicint getCurrentPage(){ 0N19R 5NN8
return currentPage; &ZUV=q%g9n
} &
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/** sy;_%,}N
* @param currentPage c;pv< lX'
* The currentPage to set. 6_h'0~3?`
*/ O6$d@r;EK]
publicvoid setCurrentPage(int currentPage){ &?gvW//L2
this.currentPage = currentPage; 7;;HP`vY
} {@w!kl~8
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/** 1O,<JrE+-
* @return FOx&'dH%@
* Returns the everyPage. O$,MdhyXC
*/ >|@i8?|E
publicint getEveryPage(){ ~i y]X:U
return everyPage; ?#0|A?U
} xf]_@T;
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/** 8Mf{6&F=
* @param everyPage oWo/QNw9
* The everyPage to set. &KS*rHgt?
*/ !+# pGSk
publicvoid setEveryPage(int everyPage){ J"Z=`I)KON
this.everyPage = everyPage; p 3*y8g-
} EFNi# D8s
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/** f Nnemn@>
* @return @XL5$k[Y
* Returns the hasNextPage. ij<6gv~ n"
*/ c;dMXv
publicboolean getHasNextPage(){ e=m=IVY#W
return hasNextPage; 1$#{om9
} fyE#8h_>4
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/** ^<VJ8jk<
* @param hasNextPage [|!A3o
* The hasNextPage to set. K7CrRT3>6
*/ IDIok~B=e
publicvoid setHasNextPage(boolean hasNextPage){ M'D l_dx-
this.hasNextPage = hasNextPage; J@vL,C)E6
} t5Oeb<REz
O.% $oV
/** :]hNw1e
* @return #7}1W[y9}l
* Returns the hasPrePage. s}3`%?,6y
*/ m=hUHA,p4
publicboolean getHasPrePage(){ <)dHe:
return hasPrePage; ;mAlF>6]\
} {5,
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/** gx',~
* @param hasPrePage j aEUz5
* The hasPrePage to set. @jxAU7!
*/ hvO
publicvoid setHasPrePage(boolean hasPrePage){ lEWF~L5=:
this.hasPrePage = hasPrePage; NB|yLkoDyI
} Oe/\@f0bLT
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/** 2`;&Uwt
* @return Returns the totalPage. C@3`n;yZ=
* F?B`rw@xr
*/ $ rU"Krf67
publicint getTotalPage(){ 1\aJ[t
return totalPage; BHZCM^
} zY=eeG+4s
vk&6L%_~a
/** Y%1 94fY$
* @param totalPage -0>gq$/N=^
* The totalPage to set. +338z<'Z!
*/ JE<w7:R&
publicvoid setTotalPage(int totalPage){ Sbp].3^j
this.totalPage = totalPage; UqwU3
} CVy\']
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} W Y]
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上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 p"UdD
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个PageUtil,负责对Page对象进行构造: o<8('j
java代码: e>] gCa
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/*Created on 2005-4-14*/ aVvma=
package org.flyware.util.page; w$##GM=Tq
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import org.apache.commons.logging.Log; bQlv b
import org.apache.commons.logging.LogFactory; g]Jt (aYK
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/** BtA_1RO
* @author Joa Rl/5eE8
* 5w+KIHhN|
*/ r&y0`M
publicclass PageUtil { 31^Jg
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privatestaticfinal Log logger = LogFactory.getLog uSgR|b;R]
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(PageUtil.class); srCpgs]h
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/** xMs!FMn[
* Use the origin page to create a new page R0g^0K.
* @param page #=g1V?D
* @param totalRecords 1p5n}|
* @return ,`
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*/ T@%\?=P
publicstatic Page createPage(Page page, int ?yc{@|
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totalRecords){ y<g1q"F
return createPage(page.getEveryPage(), [o"<DP6w
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page.getCurrentPage(), totalRecords); )UCc!
} Iz^vt#b
cE;n>ta"F
/** 'L@kZ
* the basic page utils not including exception DYDeb i6
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handler 8g0VTY4$jP
* @param everyPage r@a]fTf
* @param currentPage YO'aX
* @param totalRecords bEKh U\@=J
* @return page %b[>eIJU#
*/ Xwo%DZKN
publicstatic Page createPage(int everyPage, int ;=p3L<~c`K
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currentPage, int totalRecords){ hm*cGYV/
everyPage = getEveryPage(everyPage); *\(MG|S
currentPage = getCurrentPage(currentPage); ~ \]?5
nj
int beginIndex = getBeginIndex(everyPage, l+a1 `O
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currentPage); RY
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int totalPage = getTotalPage(everyPage, .He}f,!f<
^6On^k[|fw
totalRecords); l0 8vF$k|d
boolean hasNextPage = hasNextPage(currentPage, 02_+{vk!
mCyn:+
totalPage); D3B]
boolean hasPrePage = hasPrePage(currentPage); J= [D'h
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returnnew Page(hasPrePage, hasNextPage, j'k
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everyPage, totalPage, jsFfrS"*
currentPage, jF}-dfe
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beginIndex); Vw|P;LLl`
} M#_|WL~
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privatestaticint getEveryPage(int everyPage){ f{.4#C'
return everyPage == 0 ? 10 : everyPage; PjD9D.
} i\,I)S%yJ
p|C[T]J\@
privatestaticint getCurrentPage(int currentPage){ fX.1=BjXi
return currentPage == 0 ? 1 : currentPage;
k^Q.lb
{
} Vu,e]@
.ht-*
privatestaticint getBeginIndex(int everyPage, int L>h|1ZK
_U_O0@xi
currentPage){ !Ii[`H
return(currentPage - 1) * everyPage; hvG D`
} VsJiE0'%
o1vK2V
privatestaticint getTotalPage(int everyPage, int 5Xf]j=_
v\[+
totalRecords){ o_1N "o%
int totalPage = 0; kO5lLqE
cNbUr
if(totalRecords % everyPage == 0) a%A!DzS
totalPage = totalRecords / everyPage; GsmXcBzDw2
else OXm`n/64+
totalPage = totalRecords / everyPage + 1 ; Z}TLk^_[
g)5mr:\
return totalPage; \BuyJskE
} ^)wKS]BQ..
oOLey!uZw
privatestaticboolean hasPrePage(int currentPage){ =ecLzk"+F
return currentPage == 1 ? false : true; |r*)U(c`
} ae2Q^yLA
lYTQg~aPm
privatestaticboolean hasNextPage(int currentPage, X$;&Mdo.
|his8\C+x
int totalPage){ B>W8pZu-J
return currentPage == totalPage || totalPage == 0-uw3U<
vTgx7gP
0 ? false : true; tYXE$i
} 8PzGUn;\
ei<0,w[V1{
o K>(yC[
} CxTmW5l
oNtoqYwH
fd4C8>*7G
#1/~eIEY
F#>00b{Q
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。 gfs ;?vP
zGFD71=#
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 i84!x%|P
x ZP*%yM
做法如下: ;F#(:-:
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 F~8'3!<9
R0}1:1}$Sn
的信息,和一个结果集List: WFiX=@SS
java代码: s(nT7x+W
b,^Gj]7
'Y /0:)
/*Created on 2005-6-13*/ ?+))J~@t
package com.adt.bo; D3yTN"
r|=1{Nx
import java.util.List; Jup)A`64
ICb!AsL
import org.flyware.util.page.Page; v,S5C
4WJY+)
/** ov,|`FdU^T
* @author Joa 8ix_<$%
*/ |)+
SG>-
publicclass Result { Bz<hP*.O
ZRG
Cy5Rk
private Page page; >Jmla~A
c3 O/#*
private List content; F?|Efpzow?
*m}8L%<HT
/** X>Vc4n<}
* The default constructor =w!ik9
*/ \c
-m\|
public Result(){ HiA E9
super(); `^Vd*
} w.-x2Zg},
_"ciHYHBQ
/** cvaG[NF
* The constructor using fields ;NR|Hi]
* A<ds+0
* @param page uYMn VE"
* @param content Xj
1Oxm42
*/ :YI5O/gsk?
public Result(Page page, List content){ =3.dgtH
this.page = page; wX0D^)NtF
this.content = content; kU[hB1D5
} F#gA2VCm
^o{{kju
/** /@F'f@;
* @return Returns the content.
x%l(0K
*/ "esuLQC
publicList getContent(){ J5G<Y*q
return content; '9zW#b
}
E.h
0&UG=q
/** PjeI&@
* @return Returns the page. |n/;x$Cb
*/ E{<#h9=>
public Page getPage(){ t,?,T~#9
return page; q<
XFw-Pv
} \ZZ6r^99
5c` ;~
/** . vb##D
* @param content -N*[f9EJB
* The content to set. $6a9<&LP_
*/ Gr\ ]6
public void setContent(List content){ A?H#bRAs
this.content = content; Hu"$)V
} 509T?\r
]SCHni_
/** ^eh.Iml'@
* @param page 7GOBb|
* The page to set. -G.N
*/ ]p`y
publicvoid setPage(Page page){ rGP;0KtQ
this.page = page; G*I
} s<zN`&t
} lxyTh'
)8A.Wg4S;c
LDr?'M!D
$@L;j
k|/VNV( =0
2. 编写业务逻辑接口,并实现它(UserManager, /oT~CB..
\>6*U r
UserManagerImpl) ,)1C"'
java代码: YB"gLv?
TcaW'&(K
V
vrsf6l]
/*Created on 2005-7-15*/ .dU91> ~Ov
package com.adt.service; },8|9z#pyB
NftnbsTmy
import net.sf.hibernate.HibernateException; "z{/*uM2<
@P7'MiP]K
import org.flyware.util.page.Page; (%X *b.n=
1kvX#h&V
import com.adt.bo.Result; FOQ-KP\=,
)/jDt dI
/** gy}3ZA*F
* @author Joa cy8>M))c
*/ 8J3#(aBm
publicinterface UserManager {
"du(BZw
V
*@q< rQ
public Result listUser(Page page)throws ^*}D*=>\
7Mh'x:p
HibernateException; 9WG=3!-@
,/?J!W@m
} oJTEN}fL
Ak?9a_f
M2Nh3ijr
KR( apO
PEI$1,z
java代码: {N2GRF~c-y
@@D/&}#F
*|y'%y
/*Created on 2005-7-15*/ ww{k_'RRJ
package com.adt.service.impl; FEk9a^Xyx
Xex7Lr&
import java.util.List; X%YZQc9
CH4Nz'X2
import net.sf.hibernate.HibernateException; xRWfZ3E#
oDZZ
import org.flyware.util.page.Page; TB>_#+:
import org.flyware.util.page.PageUtil; aH"d~Y^
#`_W?-%^
import com.adt.bo.Result; i3)3.WK^
import com.adt.dao.UserDAO; jwk+&S
import com.adt.exception.ObjectNotFoundException; 8XH;<z<oJ
import com.adt.service.UserManager; =8l' [
DghyE`
/** >&.N_,*
* @author Joa w~+*Vd~U
*/ 'l/l]26rO4
publicclass UserManagerImpl implements UserManager { &MX&5@
Vu
l -XfUjJ
private UserDAO userDAO; Qr
R+3kxM
%bP+P(vZ
/** &b@_ah+f
* @param userDAO The userDAO to set. K>'4^W5d,
*/ (Mfqzy
publicvoid setUserDAO(UserDAO userDAO){ TIp\-
this.userDAO = userDAO; .uA
O.<
} %`$bQU
>J9Qr#=H2
/* (non-Javadoc) l iY/BkpH
* @see com.adt.service.UserManager#listUser @g[ijs\
Ov(k:"N
(org.flyware.util.page.Page) hWt_}'
*/ Xn"#Zy_
public Result listUser(Page page)throws #bd=G(o~6
Jj]<SWh
HibernateException, ObjectNotFoundException { l3u [
int totalRecords = userDAO.getUserCount(); '{,JuX"n
if(totalRecords == 0) H2],auBY
throw new ObjectNotFoundException dU-:#QV6
QHv]7&^rlj
("userNotExist"); qg j;E=7
page = PageUtil.createPage(page, totalRecords); Z%?>H iy'o
List users = userDAO.getUserByPage(page); ^X#)'\T
returnnew Result(page, users); :30daKo
} w8+phN(-M
d*u3]&?x&f
} %;wDB2k*
=4)8a"7#.
w%wVB/(
[ (Y@
# 9bw'm
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 pp|$y\ZzB
/\ fR6|tJ
询,接下来编写UserDAO的代码: k6 OO\=
3. UserDAO 和 UserDAOImpl: LI-ewea
java代码: p+Yy"wH:h{
Vb\^xdL>
l )r^|9{
/*Created on 2005-7-15*/ D8k >f ]
package com.adt.dao; uaD+G:{[
aAcQmq TT
import java.util.List; yodhDSO5i
UChLWf|'
import org.flyware.util.page.Page; *r4FOA%P
>]B_+r0m^
import net.sf.hibernate.HibernateException;
2X`t&zg
&|IO+'_
/** B|syb!g
* @author Joa C^?/9\
*/ 3
JlM{N6+
publicinterface UserDAO extends BaseDAO { -4Q\FLC'k
BD$Lf,_
publicList getUserByName(String name)throws J^WX^".E
dR s\e(H'
HibernateException; #- L <
'QpDx&~QP
publicint getUserCount()throws HibernateException; {DVMs|5;^
5/hgWG6.t
publicList getUserByPage(Page page)throws ga'G)d3oS
!FK)iQy$0
HibernateException; lE+Duap:
/`qQWB5b
} ;Gu(Yoa}y
"MPS&OK
=g%<xCp
8&hxU@T~
AO-~dV
java代码: aEEb1Y
8VpmcGvc3
0W
1bZPM
/*Created on 2005-7-15*/ ,-n_(U
package com.adt.dao.impl; =q[+e(,3
6EY0Fjsi
import java.util.List; p=[I;U-#H
k/Urz*O
import org.flyware.util.page.Page; [$]-W$j+
D7IhNWrgj
import net.sf.hibernate.HibernateException; B_@p@6z
import net.sf.hibernate.Query; \^cXmyQ <%
!(S.7#-r
import com.adt.dao.UserDAO; oh:.iL}j
Nbf>Y
/** Ea[SS@'R
* @author Joa Ix@nRc'
*/ s=R^2;^
public class UserDAOImpl extends BaseDAOHibernateImpl M?m@o1\;W
16ip:/5
implements UserDAO { >qMzQw2
l:a#B
/* (non-Javadoc) !h^_2IX
* @see com.adt.dao.UserDAO#getUserByName g/!tp;e
-23sm~`
(java.lang.String) dM -<aq
*/ NwKj@ Jos
publicList getUserByName(String name)throws kK&AK2
ND3|wQ`M0
HibernateException { ;t/KF"
String querySentence = "FROM user in class n"I{aJ]K
j\@&poJ(,
com.adt.po.User WHERE user.name=:name"; 'O
7>w%#
Query query = getSession().createQuery i_y%HG
n&Q0V.
(querySentence); DRVvC~M-,
query.setParameter("name", name); $}H,g}@0
return query.list(); nbv}Q-C
} }+:X= @Z@
b.
:2x4
/* (non-Javadoc) 4`sW_
ks
* @see com.adt.dao.UserDAO#getUserCount() kb\\F:w(W
*/ Eb&=$4c=
publicint getUserCount()throws HibernateException { Q ~eh_>"
int count = 0; RRpCWcIv"
String querySentence = "SELECT count(*) FROM F:Yp1Wrb <
k]c$SzJ> /
user in class com.adt.po.User"; Gg^gK*D
Query query = getSession().createQuery pe!"!xJE
R$2\Xl@qQF
(querySentence); OP``+z>
count = ((Integer)query.iterate().next OL.{lKJ3DV
h.xtkD)Y~
()).intValue(); u&j_;Y !6
return count; <.
V*]g/;
} OFZo"XtF
`{ \)Wuw
/* (non-Javadoc) DU@SXb
* @see com.adt.dao.UserDAO#getUserByPage ~qE:Nz0@
!#4b#l(e6
(org.flyware.util.page.Page) u} [.*e
*/ CSzu$Hnq
publicList getUserByPage(Page page)throws \mFgjPz
m>DJ w7<
HibernateException { cOdgBi
String querySentence = "FROM user in class k4JTc2b
fTGVG
com.adt.po.User"; ]_m(q`_
Query query = getSession().createQuery Hr(%y&0
8&y#LeM1TT
(querySentence); F ^)(
7}ph
query.setFirstResult(page.getBeginIndex()) -{p~sRc&
.setMaxResults(page.getEveryPage()); 5[`f(;
return query.list(); G4EuW *~
} MwD8a<2Dg
I7;|`jN5K
} fHgvh&FU
CeUC[cUQU
|Syulus
N1JM[<PP
: !wt/Y
至此,一个完整的分页程序完成。前台的只需要调用 <SSkCw
Md*.q^:
userManager.listUser(page)即可得到一个Page对象和结果集对象 1(WBvAPS
5?>ES*
的综合体,而传入的参数page对象则可以由前台传入,如果用 >UXNR`?
N LSJ
D
webwork,甚至可以直接在配置文件中指定。 j
HEt
D0X!j,Kc
下面给出一个webwork调用示例: +o K*5 Y
java代码: #?DoP]1Y
To,*H OP
whQJWi=ck
/*Created on 2005-6-17*/ CS;4 ysNf
package com.adt.action.user; 5M#LO@U
L1QDA}6?_Y
import java.util.List; Eo0/cln|
~6#O5plKc
import org.apache.commons.logging.Log; 1-sG`%
import org.apache.commons.logging.LogFactory; O-n JuZJgX
import org.flyware.util.page.Page; !{b4+!@p
}(9ZME<(
import com.adt.bo.Result; ` c"
import com.adt.service.UserService; ^(Wu$\SA
import com.opensymphony.xwork.Action; Upz?x{>x
CTQJ=R"
/** 8Q73h/3
* @author Joa kK.[v'[>&
*/ ZDm Y${J
publicclass ListUser implementsAction{ 3qy4nPg
;eW\41 w
privatestaticfinal Log logger = LogFactory.getLog 5 i=C?W`'
5a5)hmO RB
(ListUser.class); T1(*dVU?
mpd?F'V
private UserService userService; /1b7f'
/sdZf|Zl
private Page page; sE[
Yg8yAt
h*\u0yD)
privateList users; [-VIojs+u
+77B656
/* I
MG^L
* (non-Javadoc) NJg )S2]7
* |u+!CR
* @see com.opensymphony.xwork.Action#execute() \%&eDE 0
*/ dEZlJo@J
publicString execute()throwsException{ XmN8S_M>v
Result result = userService.listUser(page); ;KT5qiqYH
page = result.getPage(); &W{v(@
users = result.getContent(); wJh/tb=$o
return SUCCESS; ?HeUU
} <,y> W!
Y;kiU
/** Yw_!40`
* @return Returns the page. ZWQ/BgKB
*/ Hz>Dp
!
public Page getPage(){ jW>K#vj
return page; "NTiQ}i
} XJ7pX1nf
M[(pLYq:
/** od^ylg>K
* @return Returns the users. `i<Z<
<c>
*/ zpZfsn!
publicList getUsers(){ \} _,g
return users; -B?cF9
} aP#/%
Q"H/RMo-
/** L2OR<3*|Av
* @param page BlqISyrY
* The page to set. c7RQ7\
*/ iU AY
publicvoid setPage(Page page){ B:Hr{%O
this.page = page; c:""&>Z
} ri6KD
<,D*m+BWn
/** _tE55X&
* @param users 8 #:k
* The users to set. /i#";~sO
*/ L$,yEMCe
publicvoid setUsers(List users){ M{4XNE]m
this.users = users; ?$l|];m)-
} rR
8 6D
W2'!Pc,W
/** Fm*npK
* @param userService l]OzE-*$b
* The userService to set. c=X+uO-
*/ mhB2l/
publicvoid setUserService(UserService userService){ ij;P5OA
this.userService = userService; 8|zOgn{
} c3r`T{Kf
} ;a| ~YM2I
ck\W'Y*Q7
iu3L9UfL[
E;[Uhh|78!
'by+hXk
上面的代码似乎看不出什么地方设置了page的相关初值,事实上, jcb&h@T8kv
W1EYVXN
可以通过配置文件来进行配置,例如,我想每页显示10条记录,那 3#Bb4\_v
!#=3>\np+X
么只需要: Gr#3GvL
java代码: u@CQ+pnf:(
gd*2*o$g(
:2K@{~8r
<?xml version="1.0"?> ]qxl^Himq
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork Dp!91NgB p
'C]Yh."u
1.0//EN" "http://www.opensymphony.com/xwork/xwork- )]s<Czm%
x0WinLQ
1.0.dtd"> gY8$Rk
%
.ws86stFSb
<xwork> /(.:l +[w[
:
]+6l
<package name="user" extends="webwork- } `5k^J$x
tym:C7v%~
interceptors"> 5n{d jP
Ri~$hs!
<!-- The default interceptor stack name imeE&
;S '?l0
--> K/K-u
<default-interceptor-ref I]E 3&gnC
Qd{8.lB~LQ
name="myDefaultWebStack"/> qR_>41JU"
*3rs+0
<action name="listUser" O1S7t)ag
CH&{x7$he
class="com.adt.action.user.ListUser"> ml<tH2Qx3C
<param .Z
67
y^ |u'XK
name="page.everyPage">10</param> ],k~t5+
<result 7eAV2.
se`Eez}
name="success">/user/user_list.jsp</result> sRA2O/yKCE
</action> U3Z=X TB
t ^[fu,
</package> DA.k8M
W\NC3]
</xwork> N2"B\
KmTFJ,iM
w"wW0uE^
b^Re947{g
gXJBb+P
@uldD"MJ<]
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 [
'lu;1-,
vg1JN"S[
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。 r
PK.Q)g
!*Eu(abD
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 \yC /OLXq
0o"aSCq8t
W(R~K -
&29jg_'W
| @$I<
我写的一个用于分页的类,用了泛型了,hoho ao"2kqa)r
w2'q9pB+
java代码: >ItT269G
)38%E;T{X
(u} /(Ux
package com.intokr.util; ]i@73h YT
}`g-eF>p
import java.util.List; DZtpY{=Z
>Vjn]V5y
/** !@F { FR
* 用于分页的类<br> f|FS%]fCxk
* 可以用于传递查询的结果也可以用于传送查询的参数<br> "`V@?+3
* BB\GrD
* @version 0.01 ]JYE#F
* @author cheng ,>h"~X
*/ o+'|j#P
public class Paginator<E> { Y~85Z0l
privateint count = 0; // 总记录数 gS5MoW1
privateint p = 1; // 页编号 Y=O+d\_W
privateint num = 20; // 每页的记录数 rR-[CT
privateList<E> results = null; // 结果 ]}XDDPbZ}
$Gv@lZ@=
/** >kK@tJn
* 结果总数 ZBK0`7#&EH
*/ "TZY)\{L
publicint getCount(){ {pIh/0
return count; $t.oGd@N
} LhbdvJAk@
Hf?@<4
publicvoid setCount(int count){ %m\:AK[}
this.count = count; mn?F;=qE
} 3ai[ r
`\62 iUN
/** L)J1yw
* 本结果所在的页码,从1开始 f7~dn#<@
* 'E3T fM
* @return Returns the pageNo. 1vj@qw3
*/ rs{)4.I
publicint getP(){ Sk cK>i.[
return p; ;v@ G
} 6r<a
Lz.khE<
/** t.28IHJ
* if(p<=0) p=1 U
5J
_Y
* LJ/He[r|[
* @param p S3ooG1 4Ls
*/ eV|N@
publicvoid setP(int p){ "dX~J3$
if(p <= 0) ;rT'~?q
p = 1; 1"ZtE\{
"
this.p = p; LBCH7@V1yR
} >nghFm
S@HC$
/** uI7n{4W*x
* 每页记录数量 |NZi2Bu
*/ v"o"W[
publicint getNum(){ \mc0fY
return num; >0{}tRm-P&
} F tIcA"^N
LUMbRrD-
/** iAu/ t
* if(num<1) num=1 O@T,!_Zf
*/ Y7}Tuy dC
publicvoid setNum(int num){ 7z4k5d<^_
if(num < 1) o{sv<$
num = 1; xR0T'@q
this.num = num;
I/Vw2
} t^~vi'bB
8@m$(I+
/** eUA]OF@
* 获得总页数 >o?v[:u*
*/ 4f[%Bb
publicint getPageNum(){ 1l$Ei,9
return(count - 1) / num + 1; S\).0goOW
} 1y'Y+1.<
e
Wux
/** ^~YT<cJ1h
* 获得本页的开始编号,为 (p-1)*num+1 wsWFD xR
*/ {=ox1+d
publicint getStart(){ SV>tw`2
return(p - 1) * num + 1; =9jK\ T^
} O:wG/et
&