Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 {m@tt{%
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根
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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 B*w]yL(
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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 mx
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分页支持类:
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java代码: E31YkD.A
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package com.javaeye.common.util; !2^~ar{2
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import java.util.List; W0Y
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publicclass PaginationSupport { p\9}}t7n
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publicfinalstaticint PAGESIZE = 30; @65xn)CD{
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privateint pageSize = PAGESIZE; M)nh~gU
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privateList items; Q'JK *.l
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privateint totalCount; +|7N89l
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privateint[] indexes = newint[0]; "tK|/R+
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privateint startIndex = 0; e-[PuJ
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public PaginationSupport(List items, int qxsHhyB_n;
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totalCount){ r4DHALu#)
setPageSize(PAGESIZE); qvK/}
setTotalCount(totalCount); !n P4S)A
setItems(items); Q\T?t
setStartIndex(0); 8 H3u"
} 6EO@Xf7,
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public PaginationSupport(List items, int 5Pxx)F9]
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totalCount, int startIndex){ {
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setPageSize(PAGESIZE); Cb`, N
setTotalCount(totalCount); TA2ETvz^
setItems(items); KfYU.Q
setStartIndex(startIndex); CV_M |
} OK8Ho"
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public PaginationSupport(List items, int NO@`*:.^Y
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totalCount, int pageSize, int startIndex){ G6}&k[d5%
setPageSize(pageSize); -mn/Yv
setTotalCount(totalCount); U zc p
setItems(items); 'GX x|.
setStartIndex(startIndex); gmgri
} }!R*Q`m
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publicList getItems(){ o 9/,@Ri\5
return items; c5b}q@nH
} v9Sk\9}S
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publicvoid setItems(List items){ c$^v~lQS
this.items = items; 1X5Yp |Ho
} NsSZ?ky
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publicint getPageSize(){ 5J|S6x\
return pageSize; K/ &`
} 9==4T$nM[
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publicvoid setPageSize(int pageSize){ l>`66~+s,`
this.pageSize = pageSize; _q4O2Fx0
} oz)4YBf
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publicint getTotalCount(){ 0B!(i.w
return totalCount; ipg`8*My
} wytMoG\
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publicvoid setTotalCount(int totalCount){ "~._G5i.
if(totalCount > 0){ PnInsf%;
this.totalCount = totalCount; q5= ,\S3=
int count = totalCount / B["+7\c<~
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pageSize; ?[m1?
if(totalCount % pageSize > 0) G9LWnyQt
count++; nKS*y*
indexes = newint[count]; Skg/iH"(
for(int i = 0; i < count; i++){ u_
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indexes = pageSize * 0XCAnMVo
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i; 1zH?.-
} ,>7dIJqzw
}else{ a^@.C5
this.totalCount = 0; ,f>9oOqqA
} )UF'y{K}
} zPqJeYK
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publicint[] getIndexes(){ O65`KOPn
return indexes; kk6
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} T$%QK?B
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publicvoid setIndexes(int[] indexes){ GdNhEv
this.indexes = indexes; #)xlBq4cZ
} LO)!Fj4|
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publicint getStartIndex(){ b~:)d>s8wY
return startIndex; R2a99# J
} [BJzZ>cY
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publicvoid setStartIndex(int startIndex){ 2&n6:"u|
if(totalCount <= 0) YX-j|m|
this.startIndex = 0; X5VNj|IE
elseif(startIndex >= totalCount) +~iiy;i(
this.startIndex = indexes ox&?`DO
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[indexes.length - 1]; FI[BZZW
elseif(startIndex < 0) QY&c=bWAX"
this.startIndex = 0; j,^&U|!
else{ p|A ?F0
this.startIndex = indexes JN+7oh]u
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[startIndex / pageSize]; gMF6f%
} lW-h
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} d wG!]j>:_
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publicint getNextIndex(){ 0 {z8pNrc
int nextIndex = getStartIndex() + fv+ET:T%
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pageSize; U!r8}@
if(nextIndex >= totalCount) d[,Rgdd@I
return getStartIndex(); Sv /P:r
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else K'J_AMBL
return nextIndex; I@6+AU~,6
} v9Ii8{ca|
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publicint getPreviousIndex(){ \zg R]|
int previousIndex = getStartIndex() - 9]l I?j]o
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pageSize; ~&T U
if(previousIndex < 0) / kK*%TP
return0; c(
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else V.*M;T\i
return previousIndex; aH uMm&
} ;BH.,{*@B
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} wods
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抽象业务类 k6ry"W3
java代码: n5UUoBv
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/** sGhw23
* Created on 2005-7-12 -+1O*L!
*/ ^0| :
package com.javaeye.common.business; b5=|1SjR
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import java.io.Serializable; E-C]<{`O
import java.util.List; P8X9bW~GQ
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import org.hibernate.Criteria; /mz.HCs
import org.hibernate.HibernateException; K
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import org.hibernate.Session; z*jaA;#
import org.hibernate.criterion.DetachedCriteria; |}:}14ty
import org.hibernate.criterion.Projections; )u{]rb[
import |=YK2};
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org.springframework.orm.hibernate3.HibernateCallback; !;&\n3-W
import PVlCj
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org.springframework.orm.hibernate3.support.HibernateDaoS K1J |\!o
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upport; ,hI$nF0}p
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import com.javaeye.common.util.PaginationSupport; ,}'8.
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public abstract class AbstractManager extends =Mwuhk|*
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HibernateDaoSupport { hmkb!)
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privateboolean cacheQueries = false; 2! ,ndLA
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privateString queryCacheRegion; #6|ve?`I
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publicvoid setCacheQueries(boolean P=,\wM6T|
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cacheQueries){ !J;Bm,Xn6
this.cacheQueries = cacheQueries; ck0%H#BYY
} D1-/#QN$1
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publicvoid setQueryCacheRegion(String ~L<"]V+B
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queryCacheRegion){ akr2Os
this.queryCacheRegion = ](R
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}(u:K}8
queryCacheRegion; 7Ji'7$
} Xykoq"dbb
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publicvoid save(finalObject entity){ #KoI8U"
getHibernateTemplate().save(entity); |g}r
} 8*/;W&7y
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publicvoid persist(finalObject entity){ 0'F/z%SMj
getHibernateTemplate().save(entity); C)i8XX
} LWqKSNE;
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publicvoid update(finalObject entity){ J#Y0R"fo
getHibernateTemplate().update(entity); BV@q@C
} dh6kj-^;Cf
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publicvoid delete(finalObject entity){ (kO (R#M
getHibernateTemplate().delete(entity); =\2gnk~
} am? k
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publicObject load(finalClass entity, =PA?6Bm
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finalSerializable id){ hzqgsmT)
return getHibernateTemplate().load m,kYE9{
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(entity, id); pJe!~eyHm
} OT$Ne
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publicObject get(finalClass entity, \8ZVI98
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finalSerializable id){ 6e \?%,H
return getHibernateTemplate().get #]1jvB
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(entity, id); .9ZK@xM&?
} mgH~GKf^
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publicList findAll(finalClass entity){ 0#'MR.,
return getHibernateTemplate().find("from g"'BsoJ
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" + entity.getName()); *^;
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} M {'(+a[
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publicList findByNamedQuery(finalString Bt")RG
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namedQuery){ 'C7R*
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return getHibernateTemplate aO}hE2]
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().findByNamedQuery(namedQuery); O{3X`xAf
} uHacu<$=
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publicList findByNamedQuery(finalString query, 7wW x 8
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finalObject parameter){ LFi{Q{E)
return getHibernateTemplate <f:(nGj
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().findByNamedQuery(query, parameter); V[%IU'{:
} 6`'g ${U
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publicList findByNamedQuery(finalString query, aJ=)5%$6kc
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finalObject[] parameters){ l v:GiA"X
return getHibernateTemplate 'z}9BGR!
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().findByNamedQuery(query, parameters); }sqFvab<
} /,~]1&?}1
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publicList find(finalString query){ !.# g
return getHibernateTemplate().find ]vR
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(query); 32 j){[PL3
} Xsanc@w)^C
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publicList find(finalString query, finalObject JDa_;bqL
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parameter){ F
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return getHibernateTemplate().find ZR=i*y
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(query, parameter); C[TjcHoA
} .%J<zqk-
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public PaginationSupport findPageByCriteria DsxNg
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(final DetachedCriteria detachedCriteria){ .#tA .%
return findPageByCriteria !a V:T&6
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); < <0[PJ
} >\'}&oi
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public PaginationSupport findPageByCriteria $!p2Kf>/Q
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(final DetachedCriteria detachedCriteria, finalint tr0kTW$Ad
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startIndex){ r&v!2A]:
return findPageByCriteria d7g$9&/q
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(detachedCriteria, PaginationSupport.PAGESIZE, *b{Hj'H aH
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startIndex); 1bw$$QXC_
} ODpAMt"
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public PaginationSupport findPageByCriteria N1y,~Z
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(final DetachedCriteria detachedCriteria, finalint Oel%lY}m3
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pageSize, \zA3H$Df~
finalint startIndex){ `T%nGV l>\
return(PaginationSupport) nWf8r8
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getHibernateTemplate().execute(new HibernateCallback(){ rOUQg_y
publicObject doInHibernate eln$,zK/b
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(Session session)throws HibernateException { Y nTx)uW
Criteria criteria = cZ`%Gt6g
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detachedCriteria.getExecutableCriteria(session); 0#Q]>V@rO4
int totalCount = $LU|wW
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((Integer) criteria.setProjection(Projections.rowCount +WR'\15u
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()).uniqueResult()).intValue(); RcR-sbR
criteria.setProjection D&N3LH
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(null); h6`VU`pPI
List items = mMu+MXTk<
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criteria.setFirstResult(startIndex).setMaxResults V^;lg[:
m\=Cw&(
(pageSize).list(); RWDPsZC
PaginationSupport ps = H-m).^
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new PaginationSupport(items, totalCount, pageSize, n0':6*oGW
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startIndex); >*l2]3'`
return ps; 7Y4D9pw
} Csgby(D*O
}, true); 0+_;6
} ay{]Vqi9
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public List findAllByCriteria(final 6l"4F6
@'J~(#}
DetachedCriteria detachedCriteria){ tg%Sn+:
return(List) getHibernateTemplate O15~\8#'
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().execute(new HibernateCallback(){ p .~5k
publicObject doInHibernate `Y '-2Fv
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(Session session)throws HibernateException { NfCo)C-t
Criteria criteria = VdL }$CX$
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detachedCriteria.getExecutableCriteria(session); N45@)s!F9j
return criteria.list(); 5RSP.Vyx{
} `;Fs
}, true); sY}0PB
} dr"@2=Z
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public int getCountByCriteria(final VhgcvS@V
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DetachedCriteria detachedCriteria){ =NRiro
Integer count = (Integer) _z"\3hZ
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getHibernateTemplate().execute(new HibernateCallback(){ PB{5C*Y7^k
publicObject doInHibernate Dx P65wU
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(Session session)throws HibernateException { bU4\Yu
Criteria criteria = Ao *{#z
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detachedCriteria.getExecutableCriteria(session); w*4sT+
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return vb\R~%@T,
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criteria.setProjection(Projections.rowCount BQ!_i*14+
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()).uniqueResult(); 4?x$O{D5?{
} &y2DI"Ff
}, true); <2w41QZX
return count.intValue(); UzkX;UA
} l_&T)Ei
} ?d)eri8,
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用户在web层构造查询条件detachedCriteria,和可选的 S'q4va"
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 *C^`+*}OE$
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PaginationSupport的实例ps。 Zu^J X/um
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ps.getItems()得到已分页好的结果集 Y&*nj`n
ps.getIndexes()得到分页索引的数组 `H|#l\
ps.getTotalCount()得到总结果数 [PU0!W;
ps.getStartIndex()当前分页索引 !~f!O"n)3r
ps.getNextIndex()下一页索引 #_fL[j&
ps.getPreviousIndex()上一页索引 ,09d"7`X
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 U\tujK1
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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 PPj0LFA
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一下代码重构了。 :]IYw!_-p
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我把原本我的做法也提供出来供大家讨论吧: kT{d pGU9
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首先,为了实现分页查询,我封装了一个Page类: 8>V)SAI'
java代码: ^$F1U,oi
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/*Created on 2005-4-14*/ g=n /w
package org.flyware.util.page; sJ)Pj?"\?
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/** I> 3]VRi
* @author Joa Z"'tJ3Y.~
* LO
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*/ xy1R_*.F^T
publicclass Page { y[sO0u\
8Ir
= @
/** imply if the page has previous page */ [cf!%3>53
privateboolean hasPrePage; I>z0)pB
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/** imply if the page has next page */ Q"sszz
privateboolean hasNextPage; 4BAG GD2
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/** the number of every page */ vTUhIFa{
privateint everyPage; L)j<;{J/Q0
jr=erVHK
/** the total page number */ &>%9JXU
privateint totalPage; 5\eM3w'd
;*XH[>I
/** the number of current page */ VRa>bS
privateint currentPage; |jE0H!j
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/** the begin index of the records by the current 5]yby"Z?}
whvvc2
query */ I9;,qd%<T
privateint beginIndex; `E2HQA@
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/** The default constructor */ Ov PTgiI!N
public Page(){ &i?>mt
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} &)v}oHy,m
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/** construct the page by everyPage _Kf8,|+
* @param everyPage ]KE"|}B
* */ % #$K P
public Page(int everyPage){ bL]NSD
this.everyPage = everyPage; FA3YiX(-e
} X{G&r$
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/** The whole constructor */ n!$zO{P
public Page(boolean hasPrePage, boolean hasNextPage, A9\(vxxOpC
W 2.Ap
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int everyPage, int totalPage, A$ Ok^
int currentPage, int beginIndex){ tzV^.QWm
this.hasPrePage = hasPrePage; 9B<aYp)
this.hasNextPage = hasNextPage; KoKd.%
this.everyPage = everyPage; G=l-S\0@
this.totalPage = totalPage; YecV+K'p:
this.currentPage = currentPage; ;dVYR=l
this.beginIndex = beginIndex; 5Gw B1}q
} >#~>!cv6D
H4"'&A7$
/** !$L~/<&0g
* @return Cu&y',ee~
* Returns the beginIndex. JsD|igqF-
*/ Sahz*f
publicint getBeginIndex(){ ?3=y]Vb+
return beginIndex; tqXr6+!Q
} fobnK~2
@Tz}y"VG
/** *BFG{P
* @param beginIndex @Z2^smf
* The beginIndex to set. o4F(X0
*/ ALXie86a8
publicvoid setBeginIndex(int beginIndex){ 7w51UmO
this.beginIndex = beginIndex; P}8cSX9
} Ssg1p#0J
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/** 0 n}2D7
* @return 8]j*z n?,
* Returns the currentPage. ve f9*u`
*/ 4U>g0
publicint getCurrentPage(){ ^bk:g}o
return currentPage; Fv$oXg/
} BHN EP |=
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/** 7 F> a&r
* @param currentPage K;j0cxl
* The currentPage to set. ,4--3 MU
*/ GW,RE\Q:
publicvoid setCurrentPage(int currentPage){ <\`qRz0/
this.currentPage = currentPage; "el}9OitC
} ~1:_wni
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/** yIYQ.-DkS+
* @return H[2W(q6
* Returns the everyPage. g1v=a
*/ 2$TwD*[
publicint getEveryPage(){ c"lblt5
return everyPage; "6q@}sz!
} \c4D|7\=
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/** sT'j36Nc<,
* @param everyPage 08G${@D+X0
* The everyPage to set. U(/8dCyyY
*/ +vt?3i\^.
publicvoid setEveryPage(int everyPage){ k&lfxb9pd
this.everyPage = everyPage; Qv6-,6<
} "</A)y&
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/** t?wVh0gT
* @return RA1K$D ?A
* Returns the hasNextPage. |eI!wgQx
*/ ~J HEr48
publicboolean getHasNextPage(){ L$6W,D
return hasNextPage; p|g7Z
} G@P+M1c
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/** mJZB@m u?
* @param hasNextPage -QK- w>
* The hasNextPage to set. xX.kKEo"d
*/ wvRwb
publicvoid setHasNextPage(boolean hasNextPage){ .iYp9?t
this.hasNextPage = hasNextPage; W.BX6
} ?=G{2E.
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/** wOg#J
* @return M|fC2[]v B
* Returns the hasPrePage. (_]D\g~
*/ $8}'h
publicboolean getHasPrePage(){ {q! :t0X.Y
return hasPrePage; Q^*4FH!W
} 3
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/** DE+k'8\T
* @param hasPrePage UCj{
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* The hasPrePage to set. sQ.t3a3m
*/ 57KrDxE}
publicvoid setHasPrePage(boolean hasPrePage){ yz"hU
this.hasPrePage = hasPrePage; 5mX^{V&^
} YC(X=
D
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/** <99/7>#
* @return Returns the totalPage. 2!R+5^Iy
* NOmFQ)/ &
*/ VTwQD"oB
publicint getTotalPage(){ 9_O6Sl
return totalPage; $]rC-K:Z
} DMOP*;Uk
yKy
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/** k"|Fu
* @param totalPage 7AlL,&+
* The totalPage to set. qh+&Z x~
*/ EQ.K+d*K][
publicvoid setTotalPage(int totalPage){ P *&Cght>0
this.totalPage = totalPage; my0iE:
} 9N<=,!;5~s
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} ICiGZ'k
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上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 'uF75C
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个PageUtil,负责对Page对象进行构造: \_YDSmjy
java代码: ^$X|Lq
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/*Created on 2005-4-14*/ ?C- ju8]|
package org.flyware.util.page; W23Q>x&S
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import org.apache.commons.logging.Log; zXU
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import org.apache.commons.logging.LogFactory; Kr[oP3
+z:>Nl
/** hiEYIx
* @author Joa ns*:mGh
* MkhD*\D
/
*/ )+DDIq
publicclass PageUtil { w!z*?k=Da
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privatestaticfinal Log logger = LogFactory.getLog K7@|2;e
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(PageUtil.class); evpy%/D
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/** |sY
* Use the origin page to create a new page )0DgFA6k_
* @param page q#SEtyJL
* @param totalRecords I9Uj3cL\
* @return dPbn[*:
*/ $7W5smW/
publicstatic Page createPage(Page page, int z>\l%_w
KCAV
totalRecords){ H^54o$5
return createPage(page.getEveryPage(), KVh#"]<WV
1)jeawVmj
page.getCurrentPage(), totalRecords); =<7z
:]
}
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/** SM%/pu;
* the basic page utils not including exception D.Cn`O}
z&B9Yu4M7
handler ^#Mp@HK
* @param everyPage e!o\AB%d
* @param currentPage \#WWJh"W
* @param totalRecords Qc)i?Z'6
* @return page NbTaI{r
*/ LokH4A17U
publicstatic Page createPage(int everyPage, int EpQy;#=;
aSu^
currentPage, int totalRecords){ LnKgT1
everyPage = getEveryPage(everyPage); dJ/gc"7aO
currentPage = getCurrentPage(currentPage); 1KbZ6Msy
int beginIndex = getBeginIndex(everyPage, S,ea[$_
/}J_2
currentPage); Qe\vx1GRLH
int totalPage = getTotalPage(everyPage, Xdo\DQn
?Z_T3/ f
totalRecords); "(vK.-T
boolean hasNextPage = hasNextPage(currentPage, K*{RGE
:CK`v6 Qs
totalPage); %p$XK(6
boolean hasPrePage = hasPrePage(currentPage); 'RhS%l
dP(.l}O
returnnew Page(hasPrePage, hasNextPage, ]z5hTY
everyPage, totalPage, rMHh!)^#W
currentPage, 9(OeH7
d(TN(6g@
beginIndex); B@NBN&Fr
} }(
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h
privatestaticint getEveryPage(int everyPage){ &VA^LS@b
return everyPage == 0 ? 10 : everyPage; 71Za!3+
} ^<-)rzTI
%OB>FY:|
privatestaticint getCurrentPage(int currentPage){ U._fb=
return currentPage == 0 ? 1 : currentPage; >
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} jf`w8*R
o $W@@aM
privatestaticint getBeginIndex(int everyPage, int 3)ox8,{%}
_z8"r&
currentPage){ 4H%#Sn#L^!
return(currentPage - 1) * everyPage; M2p|&Z%
} <5}I6R;
ygj%VG
privatestaticint getTotalPage(int everyPage, int U~)5 {
C?>d$G8
totalRecords){ 2uN3:_w
int totalPage = 0; DbLo{mFEIj
bGL} nPo
if(totalRecords % everyPage == 0) i!*<LIq
totalPage = totalRecords / everyPage; O8b#'f~
else 036m\7+Qj
totalPage = totalRecords / everyPage + 1 ; _u^3uzu
vA!IcDP"
return totalPage; #::+# G
} 6H:
fg
Md@x2Ja
privatestaticboolean hasPrePage(int currentPage){ @vyEN.K%mm
return currentPage == 1 ? false : true; Hzm_o>^KC
} p+|8(w9A${
`ovMfL.u
privatestaticboolean hasNextPage(int currentPage, L(K 5f7\
{*F
=&D
int totalPage){ aVK,(j9u
return currentPage == totalPage || totalPage == bRyxP2
4-SU\_
0 ? false : true; 6'kQ(r>
} .U=x2txb
Y)F(-H)
0Zwx3[bq6K
} M0xhcU_
?xH{7)dO
qMVuFwPhi
`<d.I%}
Ul/m]b6-
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 {+_p?8X
n/(}|xYU
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 |[iO./zP
mOh?cjOi
做法如下: \3^V-/SJf
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 h M7 SGEV
\RR`
F .7
的信息,和一个结果集List: P HOngn
java代码: _[z)%`kay
As>Og
qOy(dG g
/*Created on 2005-6-13*/ N[3Y~HX!q
package com.adt.bo; yH-&o,
!Whx^B:
import java.util.List; HP_h!pvx
lMu9Dp
import org.flyware.util.page.Page; [<U=)!Swg
m-\_L=QzM
/** 1aS:bFi`
* @author Joa 1G12FV>M
*/ KJOb1MM
publicclass Result { nTo?~=b
qF$y
p>|#
private Page page; D=z="p\
BNjMq
private List content; <)a$5"AP
k"gm;,`
/** 7J5jf231
* The default constructor hQe78y
*/ Q`'cxx
public Result(){ FIfLDT+ Wh
super(); 8(Ptse
,
} qzO Rv
!9HWx_,|Z
/** P3W3+pwq
* The constructor using fields '[8w8,v(
* ~a2|W|?
* @param page q1L>nvE
* @param content q {
*/ ,.2qh|Ol
public Result(Page page, List content){ X=f %!
this.page = page; ! jApV
this.content = content; A#?Cts,M
} xbw;s}B
V\L%*6O
/** :%AEwRZ
* @return Returns the content. p ]jLs|tat
*/ R#y"SxD()
publicList getContent(){ s{7bu|0
return content; P"}"q ![
} V>obMr^5
u' kG(<0Y
/** B0Z>di:
* @return Returns the page. B>cT<B
*/ l+&DBw[
public Page getPage(){ Mr4,?Z&`-d
return page; 0Ba]Zo Z
}
tmBt[
m##!sF^k~J
/** NhTJB7
* @param content o$.#A]Flb
* The content to set. Hm'"I!jyO
*/ ye$_=KARP
public void setContent(List content){ !mUJ["#
this.content = content; \~%+)a%%
} `K.B`
2'S&%UyP
/** QNMZR
* @param page <>\|hno}
* The page to set. u)r/#fUZ
*/ 4joE"H6
publicvoid setPage(Page page){ vNs%e/~vj
this.page = page; <<MpeMi
} `~u=[}w
} BVb^ xL
LsERcjwwK
}UW*[dCf>C
G:$kGzhJ
Wds>'zzS
2. 编写业务逻辑接口,并实现它(UserManager, Y%"$v0D
$"/l*H\h
UserManagerImpl) apa&'%7
java代码: I &iyj99n
-@w,tbc$
cl^UFlf[
/*Created on 2005-7-15*/ u5}:[4N%I
package com.adt.service; *%;A85V/
"t4z)j;
import net.sf.hibernate.HibernateException; Cst1nGPL
~&)\8@2
import org.flyware.util.page.Page; Opu*i
X^eyrqv
import com.adt.bo.Result; Ljz)%y[s
2T2<I/")O
/** PkDt-]G.
* @author Joa 'W_NRt:
*/ x&;AY
publicinterface UserManager { -1Li&K7
EWDsBNZaI
public Result listUser(Page page)throws sX~E ~$_g
_9lMa7i
HibernateException; x!GDS>
#h=V@Dh
} 1M??@@X
c.]QIIdK
fs#9~b3
/P,1KVQPh
L D[\eJ_
java代码: e x Z/
GqCBD-@4v.
tjtvO@?1-
/*Created on 2005-7-15*/ np^&cY]
package com.adt.service.impl; b_ZvI\H
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import java.util.List; 3:jxr
30^q_|l:]
import net.sf.hibernate.HibernateException; Ql5bjlQdO
),N,!15j,
import org.flyware.util.page.Page; q("XS
import org.flyware.util.page.PageUtil; g$GGo[_0
:} =lE"2
import com.adt.bo.Result; i.6 b%
import com.adt.dao.UserDAO; x] wi&
import com.adt.exception.ObjectNotFoundException; 7(o`>7x*
import com.adt.service.UserManager; D@uVb4uK
L3I$ K+c
/** F*U(Wl=
* @author Joa }b54O\,
*/ Fj<*!J$,
publicclass UserManagerImpl implements UserManager {
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`:3nF'
private UserDAO userDAO; A;rk4)lij
?=Ceo#Er
/** _$$.5?4
* @param userDAO The userDAO to set. O
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*/ ~`BkCTT
publicvoid setUserDAO(UserDAO userDAO){ Y(6evo&IR
this.userDAO = userDAO; E}9wzPs
} !~C%0{9+u@
Nxt:U{`T'
/* (non-Javadoc) _}p[(sTV
* @see com.adt.service.UserManager#listUser }d}sC\>U
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(org.flyware.util.page.Page) [#Apd1S_
*/ eV}" L:bgJ
public Result listUser(Page page)throws $>#0RzU
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HibernateException, ObjectNotFoundException { 'v<v6vs
int totalRecords = userDAO.getUserCount(); T=YVG@fm?
if(totalRecords == 0) P x Q] $w
throw new ObjectNotFoundException !aUYidd
8:c=h/fa
("userNotExist"); vzs4tkG
page = PageUtil.createPage(page, totalRecords); ]CLM'$
List users = userDAO.getUserByPage(page); DQK?y=vf
returnnew Result(page, users); $$ *tK8#
} u_NLgM7*
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} U:8]G
z0LspRaz
vW eg1
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py\:u5QS
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 4r4 #u'Om
j=T8b
询,接下来编写UserDAO的代码: |Io:D:
3. UserDAO 和 UserDAOImpl: `l'T/F\
java代码: mOj; 0 R
:AlvWf$d
!dwZ` D
/*Created on 2005-7-15*/ P6kDtUXF
package com.adt.dao; IH=$
wc
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import java.util.List; roc DO8f
>m lQ@Z_O
import org.flyware.util.page.Page; 'dBe,@
db,?b>,EE
import net.sf.hibernate.HibernateException; 8<}=f4vUj5
<o|fH~?X
/** c6 &k?Puy
* @author Joa uz+WVmb
*/ V~*>/2+
publicinterface UserDAO extends BaseDAO { n*$g1 HG6
VK*_pEV,}
publicList getUserByName(String name)throws v)*MgfS
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HibernateException; (${:5W
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publicint getUserCount()throws HibernateException; l4i51S"
ppn 8
publicList getUserByPage(Page page)throws ,gZp/ yJ;
}Fu1Y@M%
HibernateException; uMva5o
Mj1f;$
} :(ql=+vDb4
D$4GNeB+#
9d|8c >
I
8/j|=Q,5
` Ny(S2
java代码: w;}5B~).
Nb:j]U
{1Cnrjw
/*Created on 2005-7-15*/ 75p9_)>96
package com.adt.dao.impl; _!zc <&~I
D+;4|7s+
import java.util.List; @&m]:GR
m-4#s
import org.flyware.util.page.Page; 'lE{Nj*7
T8\@CV!
import net.sf.hibernate.HibernateException; mK$E&,OkA
import net.sf.hibernate.Query; _4)
t
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import com.adt.dao.UserDAO; >;Oa|G
C)FO:lLr\
/** `q]' ^EzJ
* @author Joa @mZK[*Ak<*
*/ nI?*[y}
public class UserDAOImpl extends BaseDAOHibernateImpl 8K9HFT@yV
^A&{g.0
implements UserDAO { IY6Ll6OK
jt}oq%Bf
/* (non-Javadoc) VtzZ1/JE
* @see com.adt.dao.UserDAO#getUserByName PTe$dPB
(BtU\f#d
(java.lang.String) 9~j"6wS
*/ Gi-pi=#&cs
publicList getUserByName(String name)throws l
opl
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HibernateException { 2m*ugBO;
String querySentence = "FROM user in class p'^}J$
yn ofDGAf
com.adt.po.User WHERE user.name=:name"; uY)4y0
Query query = getSession().createQuery 5!9y nIC+>
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(querySentence); OQ2G2>p
query.setParameter("name", name); 'X+aYF}Ye
return query.list(); H#GR*4x
} ;p*L(8<YI
6[XaIco=C
/* (non-Javadoc) qU6!vgM&
* @see com.adt.dao.UserDAO#getUserCount() +7OE,RoQ
*/ 4d@0v n{
publicint getUserCount()throws HibernateException { =CFg~8W
int count = 0; 2&'uO'K
String querySentence = "SELECT count(*) FROM rkS'OC
`m1stK(PO
user in class com.adt.po.User"; +1qvT_
Query query = getSession().createQuery ?~.9:93
n5xG4.#G
(querySentence); anz7ae&P'K
count = ((Integer)query.iterate().next `::j\3B&Y-
B YB9M
()).intValue(); o(v`
return count; Z{(Gib~{N
} A<H]uQ>
nUONI+6Z/
/* (non-Javadoc) Rq(+zL(f
* @see com.adt.dao.UserDAO#getUserByPage +>ituJ
ZHA&gdK@
(org.flyware.util.page.Page) L
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*/ _`QME r?
publicList getUserByPage(Page page)throws 0j;|IU\
&flcJ`
HibernateException { _kOuD}_|
String querySentence = "FROM user in class |'i ?o
coaJDg+
com.adt.po.User"; 7m8:odeF
Query query = getSession().createQuery ')F@em
-, =)O
(querySentence); j }^?Snq
query.setFirstResult(page.getBeginIndex()) /mE:2K]C
.setMaxResults(page.getEveryPage()); c?xeBC1-
return query.list(); vA*NJ%&`
} O{]}{Ss
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} Obc,
N]c:8dOj
q{,yas7}
0x'Fi2=`
&U.y):
至此,一个完整的分页程序完成。前台的只需要调用 E.VEW;=
%u|Qh/?7
userManager.listUser(page)即可得到一个Page对象和结果集对象 )Knsy
*=E4|>Ul,
的综合体,而传入的参数page对象则可以由前台传入,如果用 I GcR5/3
S9/\L6Rmf
webwork,甚至可以直接在配置文件中指定。 DML0paOm5
S!}pL8OE
下面给出一个webwork调用示例: T?__
java代码: =g@hh)3wP
jaux:fU
p-g@cwOu
/*Created on 2005-6-17*/ B;{sr'CP
package com.adt.action.user; hW cM.
&zP\K~Nt
import java.util.List; iN`L* h
N)z]
F9Kg
import org.apache.commons.logging.Log; .fW`/BXE
import org.apache.commons.logging.LogFactory; Ug O \+cI
import org.flyware.util.page.Page; 8J9o$Se
wIbc8ze
import com.adt.bo.Result; ,%m$_wA$
import com.adt.service.UserService; zwHTtE
import com.opensymphony.xwork.Action; bL7mlh
q%^gG03.
/** 7
~ Bo*UM
* @author Joa
})w5`?Y
*/ ]7"mt2Q=3
publicclass ListUser implementsAction{ &jPsdv h
9zd)[4%=
privatestaticfinal Log logger = LogFactory.getLog |b7>kM}"
kQBVx8Uq]
(ListUser.class); kp;MNRc
<$9AP
private UserService userService; E3KPJ`=!*"
N4mQN90t
private Page page;
p|bpE F=U
gA) F
privateList users; ~d5{Q?T)
'Ph;:EMj
/* y.oJzU[p%
* (non-Javadoc) ,wEM
* wLUmRo56aR
* @see com.opensymphony.xwork.Action#execute() YGn:_9
*/ <?nr"V
publicString execute()throwsException{ I5"=b}V5
Result result = userService.listUser(page); ;~q)^.K3
page = result.getPage(); Tp6ysjao
users = result.getContent(); T<=\5mn
return SUCCESS; :{6[U=O
} LtvyWc`
xX>448=
/** p.IfJ|
* @return Returns the page. 6%xl}z]o
*/ 5astv:p,P
public Page getPage(){ tr} $82Po
return page; tw')2UGg
} t2$:*PvE
V!=]a^]:
/** ?d%}K76V<
* @return Returns the users. vtT:c.~d
*/ +Snjb0
publicList getUsers(){ J{ Vl2P?@
return users; 3IxT2@H)
} W2k~N X#@
] ge-b\
/** ;vx9xs?6
* @param page }1P
* The page to set. hU{%x#8}lK
*/ &Hqu`A/^
publicvoid setPage(Page page){ WveFB%@`;
this.page = page; V]2z5u_q
} wtKh8^:YD
}R x%&29&
/** {%Y7]*D
* @param users 90!Ib~7zH
* The users to set. Z-?9F`}
*/ 3PGyqt(
publicvoid setUsers(List users){ .wSAysiQ|P
this.users = users; v>5F[0gE
} #wyS?FP-
sFTIRVXN,
/** -iHhpD9"X
* @param userService \v_C7R;&
* The userService to set. BTyVfq
sx
*/
df'g},_
publicvoid setUserService(UserService userService){ e{,/
this.userService = userService; u/f&Wq/
} g]#Wve
} :Eyv= =
h(-&.Sm")H
A@OV!DJe]
I1~g?jpH
8rYK~Sz
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, ~aG-^BAS
M\f0
=`g
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 `,Gk1~Wv
I\~V0<"jI
么只需要: ]Yex#K
java代码: Hi9z<l=$
YP,PJnJU8
j+hoj2(
<?xml version="1.0"?> rYQ@"o0/Y
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork YC<I|&"
|5Pbc&mH8A
1.0//EN" "http://www.opensymphony.com/xwork/xwork- h :R)KM
G65N:
1.0.dtd"> `t&;Yk]-L
$4L3y
uH
<xwork> [@Y q^.6t
$lA,{Q
<package name="user" extends="webwork- ($>0&w
Y +54z/{
interceptors"> FOi`TZ8
u0b-JJ7)BQ
<!-- The default interceptor stack name {2^@jD
j:3Hm0W3
--> dy?|Q33Y"
<default-interceptor-ref wf%Ep#^6}
|"w<CKlQ
name="myDefaultWebStack"/> QL18MbfqP
cV,Dl`1r
<action name="listUser" /ASI0h
L"%eQHEC&
class="com.adt.action.user.ListUser"> `0|&T;7
<param JSK5x(GlH
D
;$+] 2
name="page.everyPage">10</param> )%w8>1}c
<result s,H(m8#>
qXhf?x
name="success">/user/user_list.jsp</result> }p?V5Qp
</action> | V,jd
]},Q`n>$
</package> +\vY; !^
}IkEyJsk
</xwork> l(\8c><m
b:cK >fh0_
+gCy@_2;
D s,"E#?
L00;rTs>
b(-t)5^}
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 8;f<q u|w
5>[sCl-
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。 0*/ r'
ss@}Dt^
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 A6 y~_dt
)k] !u
@3TkD_B&
HT=Am
^npS==Y]!.
我写的一个用于分页的类,用了泛型了,hoho P9mxY*K)%5
G[<[#$(
java代码: $]U5
t,1! `/\
{e[pSD6
package com.intokr.util; <Bb<?7q$ld
+IO1ipc4cE
import java.util.List; +;wqX]SD &
%OTA5
/** H0b6ZA%n
* 用于分页的类<br> 8xpYQ<cax
* 可以用于传递查询的结果也可以用于传送查询的参数<br> 5v>{Z0TE[6
* 6|>\&Y!Q
* @version 0.01 %v+fN?%x,d
* @author cheng ZDkD%SCy
*/ A;WwS?fyQ
public class Paginator<E> { PVS<QN%
privateint count = 0; // 总记录数 azDC'.3{p
privateint p = 1; // 页编号 qzlMn)e
privateint num = 20; // 每页的记录数 JfP\7
privateList<E> results = null; // 结果 H, XLb.
Gz[ymj)5
/** F2PLy
q
* 结果总数 mQ^@ \s
*/ X!#i@V
publicint getCount(){ ;4/dk_~p]
return count; e9Ul A
} #?$'nya*u
m]=oaj@9
publicvoid setCount(int count){ *e-ptgO
this.count = count; .KU SNrs'
} R0hctT1j
;&W;
/** aO^:dl5
* 本结果所在的页码,从1开始 jqX@&}3@
* Rgfc29(8
* @return Returns the pageNo. C'8!cPFVv
*/ sR>`QIi(a
publicint getP(){ gaw4NZd)0
return p; DD@)z0W
} da00p-U
%7NsBR!y
/** |YE,) kiF
* if(p<=0) p=1 U50s!Zt45
* S7UZGGjTk
* @param p
joChML_
*/ B|Fl,55
publicvoid setP(int p){ p- "Z'$A`
if(p <= 0) J+}+"h~.
p = 1; `sk!C7%
this.p = p; %Le :wC
} R,x> $n
d`9W
/** QM[A;WBr7
* 每页记录数量 2/v35| ?
*/ =mHkXHE~:
publicint getNum(){ 1jH7<%y
return num; @%EE0)IA
} Ic[}V0dk
O;X(pE/G
/** SUH mBo"}
* if(num<1) num=1 xH_A@hf;
*/ [F/^J|VMV
publicvoid setNum(int num){
eeW' [
if(num < 1) zH)cU%I@.
num = 1; hWq.#e6
this.num = num; dSOlD/c
} gohAp
SXRdNPXFO
/** AIZW@ Nq.5
* 获得总页数 I?_E,.)[ I
*/ V19e>
publicint getPageNum(){ }Vvsh3
return(count - 1) / num + 1; DE*MdfP0
} 5/& 1Oxo
gw_|C|!P
/**
s1X]RXX&j
* 获得本页的开始编号,为 (p-1)*num+1 t*{,Gk
*/ |h5kg<Zgo
publicint getStart(){ rkxW UDl
return(p - 1) * num + 1; s~S?D{!
} M[ x_#m|
MKU7fFN.
/** SHMl%mw
* @return Returns the results. <"*"1(wN
*/ {mNdL J
publicList<E> getResults(){ B{s]juPG
return results; ?qk@cKS
} Ci;h
RnHQq'J|\
public void setResults(List<E> results){ t,RyeS/
this.results = results; `SCy<w3$+[
} x+4vss
M]c7D`%s
public String toString(){ @4;&hP2Z:
StringBuilder buff = new StringBuilder ylk{!
f%c06Un=
(); d-~vR(tU
buff.append("{"); o6*/o ]]
buff.append("count:").append(count); >A3LA3(
c
buff.append(",p:").append(p); 1Yud~[c
buff.append(",nump:").append(num); |V lMmaz
buff.append(",results:").append bZiyapM
h-7A9:
(results); ?4,@,
ae&
buff.append("}"); b7bSTFZxC
return buff.toString(); oew|23Ytb
} W+8^P(
K
~P/]:=
} Vn'?3Eb<
cv= \g Z
GWgd8x*V