Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 _.-;5M-
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 )>c>oMgl
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据这一功能,我设计了通用的抽象Bean基类和分页类支持,代码来 $k$4%
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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 ''|#cEc)
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分页支持类: vip~'
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java代码: CNww`PX,zZ
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package com.javaeye.common.util; B*gdgM*`
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import java.util.List; %K]euEqs
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publicclass PaginationSupport { sp*Vqd
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publicfinalstaticint PAGESIZE = 30; w eQYQrN
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privateint pageSize = PAGESIZE; WlYs~(=9
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privateList items; Ks\ NE=;5
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privateint totalCount; b<]n%Q'n
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privateint[] indexes = newint[0]; 8KH\`5<
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privateint startIndex = 0; =rR~ `
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public PaginationSupport(List items, int 98.>e
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totalCount){ sFBneBub
setPageSize(PAGESIZE); 1[]&(Pa
setTotalCount(totalCount); 0D8K=h&e
setItems(items); v<fnB
setStartIndex(0); [NFNzwUB
} &)oOeRwi].
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public PaginationSupport(List items, int A 8 vbQ
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totalCount, int startIndex){ i%6;
setPageSize(PAGESIZE); SIKOFs
setTotalCount(totalCount); xTGxvGv8
setItems(items); {3!E4"p
setStartIndex(startIndex); a5G/[[cwTV
} G/v/+oX
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public PaginationSupport(List items, int C.kxQ<
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totalCount, int pageSize, int startIndex){ *SO{\bu
setPageSize(pageSize); +t2SzQ j>
setTotalCount(totalCount);
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setItems(items); O 1oxZj
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setStartIndex(startIndex); A_;8IlW
} j:w{;(1=W
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publicList getItems(){ ]QuM<ms
return items; = P
} IuZ) [*W
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publicvoid setItems(List items){ {-A^g!jT&
this.items = items; |+$%kJR=
} 1jX3ey~
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publicint getPageSize(){ S\CRG>
return pageSize; a" H WGY
} Skz|*n|eY
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publicvoid setPageSize(int pageSize){ ~y$ !48o
this.pageSize = pageSize; !`mZ0c+
} ,E|m.
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publicint getTotalCount(){ ;}z\i
return totalCount; u0`%+:]0
} p!/[K6u
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publicvoid setTotalCount(int totalCount){ 45&8weXO:'
if(totalCount > 0){ {Q<$Uo6V
this.totalCount = totalCount; ?GTU=gpQ
int count = totalCount / qT/Do?Y
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pageSize; <|?K%FP7Z
if(totalCount % pageSize > 0) dCu'>G\bP
count++; _uc\ D
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indexes = newint[count]; CDi<<,
for(int i = 0; i < count; i++){ 0R0{t=VJZ
indexes = pageSize * LB/C-n.`
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} 3Oa*%kP+
}else{ @/&b;s73
this.totalCount = 0; ESoAzo,u
} {iG@U=>
} 3zT_^;:L
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publicint[] getIndexes(){ VzJ5.mRQ
return indexes; U4G}DCU
} Tg3!R q55
}qjCTEs}
publicvoid setIndexes(int[] indexes){ v_<2H'*Q
this.indexes = indexes; RwVaZJe)l
} 1oKfy>i e
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publicint getStartIndex(){ $W;b{H=F
return startIndex; b6E<r>q
} `c+/q2M
+}Av-47`h
publicvoid setStartIndex(int startIndex){ a iCn"j
if(totalCount <= 0) 1qi@uYDug
this.startIndex = 0; ~m*,mz
elseif(startIndex >= totalCount) d1joVUYE
this.startIndex = indexes #Dfo#]k(
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[indexes.length - 1]; g+PPW88P;
elseif(startIndex < 0) TEsnN i
1
this.startIndex = 0; D7"p}PD>~
else{ [i]r-|_K
this.startIndex = indexes \C5%\4
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[startIndex / pageSize]; Iak0 [6Ey
} x7T+>
} 6Fy@s
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publicint getNextIndex(){ @DC)]C2
int nextIndex = getStartIndex() + k
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pageSize; Lhh;2r/?78
if(nextIndex >= totalCount) (Vg}Hh?p
return getStartIndex(); Q)af|GW$
else O3V.^_k;
return nextIndex; zdSh:
} XN,,cU
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publicint getPreviousIndex(){ mKq" 34F
int previousIndex = getStartIndex() - M`D$!BJr
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pageSize; 2q}..
if(previousIndex < 0) mDFlz1J,e
return0; l2hG$idC
else wcDjg&:=ml
return previousIndex; 5jq=_mHt
} @6o]chJo
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} *R% wUi
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抽象业务类 {F|48P;J
java代码: .I$}KE)
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/** #ZiT-
* Created on 2005-7-12 dPjhq(8 zU
*/ <@bA?FY
package com.javaeye.common.business; Hoz5 6y
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import java.io.Serializable; P,bd'
import java.util.List;
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import org.hibernate.Criteria; ED} 31L
import org.hibernate.HibernateException; K
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import org.hibernate.Session; i[semo\E
import org.hibernate.criterion.DetachedCriteria; /-0'
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import org.hibernate.criterion.Projections; I_ "Z:v{
import UBO^EVJ
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org.springframework.orm.hibernate3.HibernateCallback; ]B9 ^3x[:
import ?TEK=mD#u
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org.springframework.orm.hibernate3.support.HibernateDaoS AH{^spD{7,
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upport; GO5 ~!g
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import com.javaeye.common.util.PaginationSupport; yZ}d+7T}
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public abstract class AbstractManager extends ,yLw$-
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HibernateDaoSupport { Qu{cB^Ga*
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privateboolean cacheQueries = false; k4KHS<n0
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privateString queryCacheRegion; {,O`rW_eS
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publicvoid setCacheQueries(boolean \Rk$t7ZH
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cacheQueries){ lWy=)^)4
this.cacheQueries = cacheQueries; s ?l%L!
} zREJ#r
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publicvoid setQueryCacheRegion(String h5@j`{
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queryCacheRegion){ e-D4'lu
this.queryCacheRegion = 6*1$8G`$8,
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queryCacheRegion; 0kCQ0xB[a5
} J+<p+(^*v
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publicvoid save(finalObject entity){ [5 pCL0<c@
getHibernateTemplate().save(entity); W7G9Kx1Y
} E*v]:kok
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publicvoid persist(finalObject entity){ 7$b?m6fmK
getHibernateTemplate().save(entity); RSWcaATZN
} fB#XhO
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publicvoid update(finalObject entity){ u39FN?<^
getHibernateTemplate().update(entity); "zV']A>4H
} ?9U:g(v
@Y'I,e
publicvoid delete(finalObject entity){ [wcA.g* F
getHibernateTemplate().delete(entity); oP$kRfXS!<
} Z}cIA87U
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publicObject load(finalClass entity, ,@Z_{,b
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finalSerializable id){ rpU/s@%L
return getHibernateTemplate().load v}il(w;O
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(entity, id); cNP/<8dq
} kP,7Li\
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publicObject get(finalClass entity, jL4>A$
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finalSerializable id){ P%GkcV
return getHibernateTemplate().get %RFYm
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(entity, id); R+.
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} }V^e7d
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publicList findAll(finalClass entity){ 52<~K
return getHibernateTemplate().find("from {^&k!H2
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" + entity.getName()); 8gpB z'/,
} Tt6{WDscZ
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publicList findByNamedQuery(finalString TU%"jb5
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namedQuery){ QAaF@Do
return getHibernateTemplate ;6<zjV7}
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().findByNamedQuery(namedQuery); :` <psvd
} vo b$iS`>=
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publicList findByNamedQuery(finalString query, S:s
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finalObject parameter){ 91;HiILgT
return getHibernateTemplate ?Leyz
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().findByNamedQuery(query, parameter); U?6yke
} ^uBwj}6
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publicList findByNamedQuery(finalString query, ?Y!^I2Y6
@W [{2d
finalObject[] parameters){ i_YW;x
return getHibernateTemplate 97x%2.\:
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().findByNamedQuery(query, parameters); [`bZ5*&
} *SGlqR['\e
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publicList find(finalString query){ z_)`g`($
return getHibernateTemplate().find z+6QZQk
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(query); pDhY%w#
} lu3.KOD/
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publicList find(finalString query, finalObject $F1_^A[
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parameter){ ruHrv"29
return getHibernateTemplate().find .WO/=#O
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(query, parameter); kC|Tubs(
} %L cH>sV
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public PaginationSupport findPageByCriteria 0:PSt_33F
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(final DetachedCriteria detachedCriteria){ r:#Q9EA
return findPageByCriteria uri*lC
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); tWRf'n[+]
} V@Kn24''
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public PaginationSupport findPageByCriteria Q%M_
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(final DetachedCriteria detachedCriteria, finalint ]F_r6 *<
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startIndex){ Uir*%*4:
return findPageByCriteria ?+Hp?i$1
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(detachedCriteria, PaginationSupport.PAGESIZE, )DRkS,I
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startIndex); #'c%
} v<+4BjV!J}
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public PaginationSupport findPageByCriteria U%n,XOJ
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(final DetachedCriteria detachedCriteria, finalint !(yT7#?hP
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pageSize, rx}*u3x=
finalint startIndex){ F1\`l{B,\
return(PaginationSupport) &!OGIYC(
qlEFJ5;
getHibernateTemplate().execute(new HibernateCallback(){ E{I)]h
publicObject doInHibernate y,^";7U
gs-@hR.,s0
(Session session)throws HibernateException { !4pr{S
Criteria criteria = Gb?g,>C
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detachedCriteria.getExecutableCriteria(session); EM=xd~H
int totalCount = UIz:=DJ
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((Integer) criteria.setProjection(Projections.rowCount {Evcc+Eq
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()).uniqueResult()).intValue(); yqYhe-"
criteria.setProjection ,y{0bq9*2
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(null);
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List items = 6SV7\,2M
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criteria.setFirstResult(startIndex).setMaxResults %`eJ66T
/Ht/F)&P
(pageSize).list(); ,zD_% ox
PaginationSupport ps = **.:)
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new PaginationSupport(items, totalCount, pageSize, RA}U#D:$i
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startIndex); }$<^wt
return ps; v7L"`
} rNZO.qijz
}, true); T0YDfo
} ^DzL$BX
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public List findAllByCriteria(final di--:h/
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DetachedCriteria detachedCriteria){ C`3V=BB
return(List) getHibernateTemplate mF}c-
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().execute(new HibernateCallback(){ :Jjw"}SfK#
publicObject doInHibernate IX"ZS
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(Session session)throws HibernateException { 6$;L]<$W>
Criteria criteria = (*MNox?w
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detachedCriteria.getExecutableCriteria(session); 8W;xi:CC
return criteria.list(); c%ZeX%p
} E(%
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}, true); AfUZO^<
} H_Iim[v#
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public int getCountByCriteria(final 8^8>qSD1
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DetachedCriteria detachedCriteria){ ]7v81G5E
Integer count = (Integer) Wgav>7!9
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getHibernateTemplate().execute(new HibernateCallback(){ O+p]3u
publicObject doInHibernate MF&3e#mdB
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(Session session)throws HibernateException { ``+c`F?5
Criteria criteria = cES;bwQ
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detachedCriteria.getExecutableCriteria(session); ]{(l;k9=e
return m dC`W&r
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criteria.setProjection(Projections.rowCount n"mJEkHE
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()).uniqueResult(); }iD$4\ L
} GhtbQM1[H
}, true); K?9WY]Ot
return count.intValue(); "!xvpsy
} $U ~=.!_du
} zpbcmQB*
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用户在web层构造查询条件detachedCriteria,和可选的 cT_uJbP+
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 *C5:#A0
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PaginationSupport的实例ps。 =
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ps.getItems()得到已分页好的结果集 be&6kG
ps.getIndexes()得到分页索引的数组 h0T< :X
ps.getTotalCount()得到总结果数 c =jcvDQ6W
ps.getStartIndex()当前分页索引 NR;q`Xe-
ps.getNextIndex()下一页索引 A
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ps.getPreviousIndex()上一页索引 Jz=;mrW
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 -zPm{a
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,尤其是上面的示例代码,让我着实觉得该对我原来的分页查询做 Z"l`e0{
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一下代码重构了。 8dr0 DF$c
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我把原本我的做法也提供出来供大家讨论吧: ?+bTPl;%'
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首先,为了实现分页查询,我封装了一个Page类: JCM)N8~i
java代码: Coga-: 2vu
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/*Created on 2005-4-14*/ !}iLO0
package org.flyware.util.page; ;X+G6F'
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/** /Lq;w'|I
* @author Joa x%b]ea
* b%=1"&JI:
*/ {[l'S
publicclass Page { F;cI0kP=>
F(T=WR].o
/** imply if the page has previous page */ db{NKwpj'
privateboolean hasPrePage; j%6|:o3G(
;6DR.2}?>
/** imply if the page has next page */ p6<E=5RRd1
privateboolean hasNextPage; d [\>'>
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/** the number of every page */ RH<@c^ S
privateint everyPage; j)6@q@P/
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/** the total page number */ @#bBs9@gv
privateint totalPage; F@>w&A~K
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/** the number of current page */ &@mvw=d
privateint currentPage; +}Qv6s#
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ez)
/** the begin index of the records by the current ZkJY.H-F
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query */ $=\oJ-(!@S
privateint beginIndex; 5"76R
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/** The default constructor */ pKOT Qf
public Page(){ H j>L>6>
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} Jm{As*W>
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/** construct the page by everyPage N&R
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* @param everyPage U92B+up-
* */ f9h:"Dnzin
public Page(int everyPage){ OlD7-c2L]
this.everyPage = everyPage; Ktg&G<%J0
} m
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/** The whole constructor */ 9b{g+lMZo
public Page(boolean hasPrePage, boolean hasNextPage, "2y7l
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int everyPage, int totalPage, J8qu]{0I"
int currentPage, int beginIndex){ TzD:bKE&
this.hasPrePage = hasPrePage; o=a:L^nt,
this.hasNextPage = hasNextPage; 7?kXgR[#d
this.everyPage = everyPage; #C;#$|d
this.totalPage = totalPage; kphy7>Km
this.currentPage = currentPage; zJB+C=]D7H
this.beginIndex = beginIndex; ,g<>`={kK+
} :kf3_?9rc
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/** )w}*PL
* @return e3HF"v]2!
* Returns the beginIndex. pAPQi|CN
*/ F1Zk9%L%9$
publicint getBeginIndex(){ \K4CbZ,.
return beginIndex; IkE'_F
} ve64-D
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/** 7|{%CckN
* @param beginIndex ByB0>G''.
* The beginIndex to set.
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*/ 8KtF<`A)
publicvoid setBeginIndex(int beginIndex){ I&Eg-96@
this.beginIndex = beginIndex; N#2nH1C
} PBPJ/puW
S7\|/h:4
/** nU">> 1!U
* @return d-A%ZAkE]
* Returns the currentPage. AW{/k'%xw
*/ 1*x5/b
publicint getCurrentPage(){ @BB,i /
return currentPage; Y/:Q|HnXQ
} T$>=+U
IdC k
/** nKZRq&~^E
* @param currentPage egIS rmL+X
* The currentPage to set. ];wohW%
*/ FZ}C;yUPD
publicvoid setCurrentPage(int currentPage){ w
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this.currentPage = currentPage; ZT3jxwe
} Wb}0-U{S'
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/** ;4O;74`Zh
* @return R&-W_v+
* Returns the everyPage. ]i_):@
*/ <R]Wy}2-
publicint getEveryPage(){ $F
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return everyPage; Y
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} !513rNO
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/** Z?G3d(YT
* @param everyPage v#AO\zYKd
* The everyPage to set. T_;G))q'
*/ DrVbx
publicvoid setEveryPage(int everyPage){ F4aJr%!\6S
this.everyPage = everyPage; ,2:L{8_L
} !&`7
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/** ="[+6X
* @return YM,D`c[pX
* Returns the hasNextPage. !Z9ikn4A
*/ ,y{fqa4
publicboolean getHasNextPage(){ iM-hWhU
return hasNextPage; [wpt[zG
} (*^E7
[w
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/** d+$[EDix
* @param hasNextPage =4%WOI
* The hasNextPage to set. Pq_ApUZa
*/ 0"D?.E"$r
publicvoid setHasNextPage(boolean hasNextPage){ #ui%=ja[:~
this.hasNextPage = hasNextPage; `\/Wa h}I
} HN&vk/[
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/** Q*{ H]
* @return a1Y _0
* Returns the hasPrePage. @+Anv~B.
*/ W3{5Do.h
publicboolean getHasPrePage(){ oR%E_g?mI~
return hasPrePage; )F9%^a(
} mrBhvp""
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/** !nD[hI8P
* @param hasPrePage JeSkNs|vB
* The hasPrePage to set. >!ZyykAs
*/ ;{)@ghD
publicvoid setHasPrePage(boolean hasPrePage){ uS+b* :
this.hasPrePage = hasPrePage; fqp7a1qQl
} FK,r<+h
jzOMjz~:)
/** *~aI>7H
* @return Returns the totalPage. CI]U)@\U
* AXv3jH,HF
*/ w}KcLaI
publicint getTotalPage(){ z%-"'Y]
return totalPage; 1PjX:]:
} XS~w_J#q
9$w)_RX9W
/** '1T v1
* @param totalPage |Z)/
* The totalPage to set. UqQZ
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*/ (h(ZL9!
publicvoid setTotalPage(int totalPage){ q|Tk+JH{5
this.totalPage = totalPage; TbUkqABm
} S>zKD
c\?/^xr'!}
} Mh@ylp+q
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}&^bR)=
hFF&(t2{^
3n"&$q6
上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 j1C0LP8
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个PageUtil,负责对Page对象进行构造: ~#xs
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java代码: G37L 9IG-M
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/*Created on 2005-4-14*/ )pj \b[
package org.flyware.util.page; 'aSORVq^e[
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import org.apache.commons.logging.Log; ^{,},
i
import org.apache.commons.logging.LogFactory; GTX&:5H\t
"+OMo-<K7
/** ku8Z;ONeH
* @author Joa %x)U8
* Lgw@y!Llij
*/ D.JVEKLkU
publicclass PageUtil { 1>*<K/\qg
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privatestaticfinal Log logger = LogFactory.getLog yD'h5)yu
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(PageUtil.class); ^hTJp{
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/**
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* Use the origin page to create a new page Kct +QO(
* @param page ",oUVl
* @param totalRecords gI$`d?[0{
* @return RB@gSHOc?
*/ 2]KPW*V
publicstatic Page createPage(Page page, int y(g
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totalRecords){ Z@Z`8M@Q,
return createPage(page.getEveryPage(), l"g%vS,;`
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page.getCurrentPage(), totalRecords); N>iCb:_
T;
} 2Nzcej
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/** rx)Q]
* the basic page utils not including exception X0L{#U
;0{*V5A
handler f4^_FK&
* @param everyPage T0C'$1T
* @param currentPage V,,iKr@TG
* @param totalRecords W u{nC
* @return page Qc/J"<Lx
*/ NX/)Z&Fx:
publicstatic Page createPage(int everyPage, int <o`]wOrl
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currentPage, int totalRecords){ qa#F}aGd
everyPage = getEveryPage(everyPage); %gB0D8,vo
currentPage = getCurrentPage(currentPage); <\NXCUqDpo
int beginIndex = getBeginIndex(everyPage, $^GnY7$!>
8`<GplO
currentPage); :RG6gvz
int totalPage = getTotalPage(everyPage, $9$NX/P
q|\Cp
totalRecords); [X\2U4
boolean hasNextPage = hasNextPage(currentPage, b&&'b)
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totalPage); s_Gp +-
boolean hasPrePage = hasPrePage(currentPage); s_$@N!
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returnnew Page(hasPrePage, hasNextPage, 3j#F'M)s{
everyPage, totalPage, ;trR'~
currentPage, /pEkig7M
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beginIndex); :a`m9s 4
} w Nnb@
s)=7tHoqB)
privatestaticint getEveryPage(int everyPage){ ^4i3 #}
return everyPage == 0 ? 10 : everyPage;
WR%iUO40
} "[,XS`
rZ7 Ihof
privatestaticint getCurrentPage(int currentPage){ %&NK|M+n
return currentPage == 0 ? 1 : currentPage; ^hJ,1{o
} efm<bJB2
C\K--
privatestaticint getBeginIndex(int everyPage, int =$J2
H|?`n
uiD
currentPage){ P@ u%{
return(currentPage - 1) * everyPage; NmXTk+,L#
} 4G2V{(@QiZ
\v_(*
privatestaticint getTotalPage(int everyPage, int A5\S0l$Q
Z]CH8GS~<
totalRecords){ h[?28q$
int totalPage = 0; z9ZAY!Zhq]
;E_{Zji_e
if(totalRecords % everyPage == 0) -0Ek&"=Z^
totalPage = totalRecords / everyPage; 75ob1h"
else 1:8: yFV
totalPage = totalRecords / everyPage + 1 ; 9IMcp~zX
mB`r6'#=
return totalPage; 4)z](e$
} ^W*/!q7H
TUt)]"h<
privatestaticboolean hasPrePage(int currentPage){ a6OT2B
return currentPage == 1 ? false : true; OX2\H
} =r2d{
gf@Dy6<
privatestaticboolean hasNextPage(int currentPage, H?m2|.
~%ZO8X:^
int totalPage){ @AFLF X]
return currentPage == totalPage || totalPage == hb{(r@[WHv
kaLRI|hC
0 ? false : true; L.'N'-BV
} l/5/|UE9
`N0E;=g
~czt=
} DDEn63{
[iD!!{6+
X"]ZV]7(]s
'n=D$j]X
}Z|a?J@CZm
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。
slbV[xR
~F-,Q_|-
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 >JhQ=j
6{6tg>|L)
做法如下: %F7k| Na
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 Yp8$0KK
IM+PjYJ
的信息,和一个结果集List: R!=XMV3$PH
java代码: .6*A~%-=[d
BeRn9[
~H.;pJ{ 8
/*Created on 2005-6-13*/ \a#2Wm
package com.adt.bo; 8I'?9rt2M
bYz:gbs]4|
import java.util.List; sQkP@Y
*,(`%b[
import org.flyware.util.page.Page; =J,:j[D(
z'm;H{xf
/** 5BZ5Gl3
* @author Joa d@<XR~);
*/ $FoNEr&q
publicclass Result { 9"rATgN1
px*MOHq K
private Page page; l[xwH 9'
-;v:.
[o.
private List content; Ez)Go6Q
t9kgACo/M
/** lyyi?/W%
* The default constructor GM5::M]fS
*/ mxIEg?r(
public Result(){ m{g{"=}YR
super(); yC
-4wn*
} C-Mop,w
5)vXmAD/0
/** l"+=z.l6;
* The constructor using fields bvoR?D\-"
* xn-n{U"
* @param page C$P3&k#W
* @param content 8ydOS
*/ 6l4l74
public Result(Page page, List content){ p(v.sP4w
this.page = page; }*%%GPJ
this.content = content; <rU(zm
} cj[y]2{1h
gG}<l ':
/** xN5}y3
* @return Returns the content. j/sZ:Q
*/ h:|aQJG5
publicList getContent(){ "m!Cl-+u
return content; #pIb:/2a_
} 6wGf47
P6MT[
/** Y!5-WXH
* @return Returns the page. $ZA71TzMV
*/ yEH30zSt
public Page getPage(){ @A:Xct
return page; ?vXy7y&4
} _^KD&t%!+y
}{[F+|\>,e
/** aJub("
* @param content xHf
l>C'
* The content to set. noacnQ_I$
*/ YcIk{_N3
public void setContent(List content){ /t816,i
this.content = content; t({:TQ
} ]1klfp,`
|[*b[O
1W
/** 8 }-"&-X
* @param page K\uR=L7
* The page to set. FsD}Nk=m~
*/ P?>p+dM
publicvoid setPage(Page page){ =ahD'*R^A
this.page = page; *b> ~L
} .6r&<*
} U:_&aY_
:Bl $c,J
xC|7"N^/
*r%=p/oQ}B
SA'
zy45
2. 编写业务逻辑接口,并实现它(UserManager, hse$M\5
!?]NMf_
UserManagerImpl) NKRNEq!
java代码: LdA&F&
pI
gzeG5p
`*WR[c
/*Created on 2005-7-15*/ GR/
p%Y(
package com.adt.service; 90Q}9T\
hEDj"`Px
import net.sf.hibernate.HibernateException; 'l2`05
9Czc$fSSt
import org.flyware.util.page.Page; Ur_~yX]Mo
m+CvU?)gJ
import com.adt.bo.Result; F$d`Umqs;P
/']Gnt G.
/** ?L'ijzP
* @author Joa kYx|`-PA<r
*/ 0nBAO
publicinterface UserManager { zg[ksny
d]CRvzW
public Result listUser(Page page)throws pVLfZ?78
-V(5U!^B
HibernateException; 3HWI;
E:#VS~
} 7,Nd[
oL*7
k{uc%6s
V0"UFy?i
JWC{ "6
p5E|0p
java代码: +[:}<^p?cG
Z>'.+OW
6:@tHUm
/*Created on 2005-7-15*/ @va6,^)
package com.adt.service.impl; 7|*|xLrVY
]^R;3kU4Q
import java.util.List; D[ny%9 :
" J$vt`
import net.sf.hibernate.HibernateException; wtaeF+u-R-
*joM[ML` 6
import org.flyware.util.page.Page; iN<Tn8-YH6
import org.flyware.util.page.PageUtil; a>6!?:Rj
)/UPDdO
import com.adt.bo.Result; FSC74N/
import com.adt.dao.UserDAO; s@Y0"
import com.adt.exception.ObjectNotFoundException; a,!c6'QE
import com.adt.service.UserManager; 1jO/"d.8n
Za5*HCo
/** Gw$U0 HA[,
* @author Joa o^biO!4,
*/ 0fwo8NgX
publicclass UserManagerImpl implements UserManager { (eFHMRMv~
NJwcb=*
private UserDAO userDAO; Y ~xcJH
c=h{^![$
/** %\2
ll=p1
* @param userDAO The userDAO to set. Z#%4QIz?
*/ NbSkauF~b
publicvoid setUserDAO(UserDAO userDAO){ X^7bOFWE
this.userDAO = userDAO; zq8LQ4@ay
} [*Wq6n
Jr|"` f%V
/* (non-Javadoc) vQ$ FMKz7
* @see com.adt.service.UserManager#listUser ,a_\o&V
z1*8 5?
(org.flyware.util.page.Page) *q\Ve)E}
*/ FlttqQQdf
public Result listUser(Page page)throws fMy7pXa_
b~z1%?
HibernateException, ObjectNotFoundException { ,aU_bve
int totalRecords = userDAO.getUserCount(); ^3^n|T7le
if(totalRecords == 0) "oz qfh
throw new ObjectNotFoundException ^g"G1,[%w
>iDV8y
("userNotExist"); `a*[@a#
page = PageUtil.createPage(page, totalRecords); $b
QD{ {
List users = userDAO.getUserByPage(page); N[~RWg
returnnew Result(page, users); )\8l6Gw
} Dqs{n?@n
$_onSYWr
} %@Bl,!BJ,
!X*+Ct^
1.6yi];6
WnyEdYA
[2"a~o\
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 7o-umZ}8
p HXslmrD
询,接下来编写UserDAO的代码: f![?og)I%
3. UserDAO 和 UserDAOImpl: sB"Oi|#lk
java代码: 7jQOwzj
4$oNh)+/h
40w,:$
/*Created on 2005-7-15*/ N7v7b<6
package com.adt.dao; Tu"bbc
&!SdO<agZ
import java.util.List; p8aGM-+40W
<%Zg;]2H`
import org.flyware.util.page.Page; _Ryt|# y
c|.~f+
import net.sf.hibernate.HibernateException; G~5EAeG
{N42z0c
/** &`Oj<UyJY
* @author Joa 0JN>w^
*/ ["TUSf]
publicinterface UserDAO extends BaseDAO { gdPv,p19L
R*|y:T,H
publicList getUserByName(String name)throws 5|z>_f.^pS
&@p _g8r#
HibernateException; c6.S jV
(NR8B9qLN
publicint getUserCount()throws HibernateException; :m#[V7
%
P
.(L
publicList getUserByPage(Page page)throws K%h9'}pq>1
@~,&E*X! .
HibernateException; 1zqIB")s>
lI~T>Lel2
} ZfsM($|a
7}>Zq`]~
j}t"M|`
_IYd^c
T#KF@8'-
java代码: k<(G)7'gm
}tJRBb
oM\b>*
/*Created on 2005-7-15*/ Xo[j*<=0
package com.adt.dao.impl; DLggR3K_\
.
7*k}@k
import java.util.List; .,[NJ:l
+}1h
import org.flyware.util.page.Page; &\6Buw_
gCfAy=-,V
import net.sf.hibernate.HibernateException; m.!n|_}]
import net.sf.hibernate.Query; mUSrC U_}
9j<qi\SSI
import com.adt.dao.UserDAO; k@:M#?(F
Bu_/yKW
/** y.vYT{^
* @author Joa M~/7thP{
*/ R<(kiD\?]
public class UserDAOImpl extends BaseDAOHibernateImpl {;mT.[
t7#lRp&
implements UserDAO { r'*x><m'
3kqO5+,C
/* (non-Javadoc) KTLq~Ru
* @see com.adt.dao.UserDAO#getUserByName Rn?Yz^
1q
3lr9nBR
(java.lang.String) u*}[fQ`aF
*/ I
"Qf};n
publicList getUserByName(String name)throws |p_\pa1&
^V6cx2M
HibernateException { 7 6 nrDE
String querySentence = "FROM user in class \EI<1B
J34/rL/s
com.adt.po.User WHERE user.name=:name"; /Q]6"nY
Query query = getSession().createQuery }OZut!_
l/*NscYtQ
(querySentence); 6="Qwrk
query.setParameter("name", name); 0SS,fs<w3
return query.list(); vX?MB
} Lsu_f'p0
>%6a$r~@
/* (non-Javadoc) ]cQYSN7!SY
* @see com.adt.dao.UserDAO#getUserCount() fG dT2}gd
*/ mv1g2f+
publicint getUserCount()throws HibernateException { JJC YM
int count = 0; xD.Uh}:J
String querySentence = "SELECT count(*) FROM +|0f7RB+R
2><=U7~
user in class com.adt.po.User"; /6fa
7;
Query query = getSession().createQuery X%X`o%AqC
=:fN
(querySentence); U~3uu&/r
count = ((Integer)query.iterate().next >;qAj!'
Q'
b@5o
()).intValue(); 9!XXuMWU<
return count; 4e`GMtp
} V8KdY=[
"kb[}r4?
/* (non-Javadoc) ~?6M4!u
* @see com.adt.dao.UserDAO#getUserByPage ~W/|RP7S
IN^dJ^1+
(org.flyware.util.page.Page) OkNBP0e}
*/ ^+J3E4
publicList getUserByPage(Page page)throws =`st1K
Xmb001
HibernateException { s2f6;Yc
String querySentence = "FROM user in class <Pn]{N
LC>bZ!(i#
com.adt.po.User"; -tPia=^
Query query = getSession().createQuery p[LPi5
VZz>)Kz:
(querySentence); 2K:Rrn/cR
query.setFirstResult(page.getBeginIndex()) 6[x6:{^J
.setMaxResults(page.getEveryPage()); [[XbKg`"?
return query.list(); h/goV
} {)`tN&\
XfZ^,'z
} OUtXu7E$
D`4>Wh/H
BT *z^ZH
WY& [%r
&"gQrBa
至此,一个完整的分页程序完成。前台的只需要调用 #r,LV}*qg
|YnT;q
userManager.listUser(page)即可得到一个Page对象和结果集对象 C<B+! 16
a>H8,a
的综合体,而传入的参数page对象则可以由前台传入,如果用 5jNDr`pnu
/gH[|d
webwork,甚至可以直接在配置文件中指定。 %|izt/B
[`n)2}
k
下面给出一个webwork调用示例: XG!s+ShFV
java代码: :aHLr[%Mz
L,\wB7t
b[/uSwvi
/*Created on 2005-6-17*/ c0U=Hj@@
package com.adt.action.user; {t%Jc~p{
fbrCl!%P
import java.util.List; zn)Kl%N^
"?HDv WP=w
import org.apache.commons.logging.Log; "3;b,<0
import org.apache.commons.logging.LogFactory; 'eYM;\%('
import org.flyware.util.page.Page; bXNM.K
#S|DoeFs
import com.adt.bo.Result; 6%A_PP3Z
import com.adt.service.UserService; X,mqQ7+
import com.opensymphony.xwork.Action; 4:0y\M5u
Vh}F#~BrI
/** H&*KpOL
* @author Joa HU1ZQkf
*/ bu:%"l
publicclass ListUser implementsAction{ `JAM]qB"
X/qLg+X
privatestaticfinal Log logger = LogFactory.getLog "i^<
H
`^mY*Cb e
(ListUser.class); BM>'w,$KL
dWi:V7t+
private UserService userService; $6DA<v^=z
&YOks.k
private Page page; 7#[8td
*l.tsICmbP
privateList users; @,Kl"i;
xH4Qv[k
Q7
/* aovw'O\Q
* (non-Javadoc) L ]Y6/Q
* Z=.$mFE\
* @see com.opensymphony.xwork.Action#execute() o,gH*
*/ 8`B]UcL)
publicString execute()throwsException{ 9#MY(Hr
Result result = userService.listUser(page); -d)+G%{
page = result.getPage(); p0sq{d~
users = result.getContent(); o>jM4sk$
return SUCCESS; Ad)::9K?J
} 6k+4R<
"CY#_)
/** Wi2Tg^
* @return Returns the page. > }fw7 X
*/ Bm$(4
public Page getPage(){ y!u=]BE
return page; *LOUf7`
} 1+ib(MJ<:#
hM "6-60
/** rE?Fp
* @return Returns the users. c`O(||UZT
*/ (T|q]29
publicList getUsers(){ Ba#wW
E
return users; chakp!S=
} Vk:] aveW
.8dlf7* ,
/** "pMx(
* @param page kCHYLv3.
* The page to set. tl"?AQcBR
*/ yOswqhz
publicvoid setPage(Page page){ Yaix\*II
this.page = page; LK:J kjp^
} C
)J@`E
%DhM }f
/** srQ]TYH ,
* @param users M37GQvo
* The users to set. Nv5)A=6#AA
*/ +rFAo00E|
publicvoid setUsers(List users){ 0BrAgv"3a_
this.users = users; 7'zXf)!
} NbPNcjPL
jz$ ]"\G#
/** ;!(GwgllD
* @param userService 9/#?]LJ
* The userService to set. Xy]Pmt
*/ yvIzgwN%s!
publicvoid setUserService(UserService userService){ P$#{a2
this.userService = userService; SX]uIkw
} 5j~1%~,#
} ,X}Jpi;/
wAKm]?zB>
Bdr'd? u<A
>K n7A
&>A<{J@VL
上面的代码似乎看不出什么地方设置了page的相关初值,事实上, i_f\dkol
!hjA
可以通过配置文件来进行配置,例如,我想每页显示10条记录,那 h,zM*z A_
l4$Iv:
么只需要: /i)>|U
4
java代码: N~|Z@pU"
X" Upml
s8.SEk|pB
<?xml version="1.0"?> SLU$DW;t
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork C K9FAuU
G\(cnqHk
1.0//EN" "http://www.opensymphony.com/xwork/xwork- 7m4*dBTr
} /*U~!t
1.0.dtd"> VRB!u420
K_ Od u^
<xwork> @p<t JR"M
]sZ!
-q'8
<package name="user" extends="webwork- Seh(G
]Ns)fr6
interceptors"> xG WA5[YV
YL&)@h
<!-- The default interceptor stack name Q!y%N&
`8/D$
--> J%FF@.)k
<default-interceptor-ref ;6M [d
K$KVm^`
name="myDefaultWebStack"/> lWakyCS
{I8C&GS
<action name="listUser" W1_.wN$,5
/|m0)H.>
class="com.adt.action.user.ListUser"> 4n} a%ocv^
<param K05U>151
.'PS L
name="page.everyPage">10</param> eX'U d%
<result I8f='
C`=YGyj=TL
name="success">/user/user_list.jsp</result> U:0Ma6<
</action> [`kk<$=,&
w+u1"
</package> NwyNl
L;-V Yo#
</xwork> K%ptRj$
~P BJ~j+G
dh_c`{9
^[6el_mj
$`[TIyA9!
DY\~O
这样就可以通过配置文件和OGNL的共同作用来对page对象设置初值 s_}`TejK
cH6++r
了。并可以通过随意修改配置文件来修改每页需要显示的记录数。 :-Ml?:0_X
[@_W-rA
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 .(99f#2M:
]0XlI;ah
VWc)AfKe
Bo$dIn2_
_:]g:F[
#
我写的一个用于分页的类,用了泛型了,hoho tb4^+&.GS
:DrF)1C
java代码: C55Av%-=
xp}M5|
wJC F"e
package com.intokr.util; erhez
&z#`Qa3NI
import java.util.List; U$46=F|
,KCxNdg^#-
/** 6Ey@)p..E
* 用于分页的类<br> waU2C2!w
* 可以用于传递查询的结果也可以用于传送查询的参数<br> Y5c[9\'\
* wjfq"7Q
* @version 0.01 6qSsr]
* @author cheng {1gT{2/~@
*/ ^J;rW3#N8
public class Paginator<E> {
C TKeY
privateint count = 0; // 总记录数 ^YJ%^P
privateint p = 1; // 页编号 Z~].v._YV)
privateint num = 20; // 每页的记录数 Zo,066'+[.
privateList<E> results = null; // 结果 YmCu\+u
W{c
Z7$d
/** GVhy
}0|
* 结果总数 k{H7+;_
*/ z'7XGO'Lo
publicint getCount(){ ~1{ppc+
return count; E\ls- (,
} 3m| C8:
THARr#1b};
publicvoid setCount(int count){ '50}QY_R.
this.count = count; ,q;?zcC7
} u 7:Iv
A"z9t#dv@
/** 74 &q2g{
* 本结果所在的页码,从1开始 `FEa(Q+s
* %lD+57=
* @return Returns the pageNo. S9{A}+"K
*/ jtUqrJFlQ
publicint getP(){ &isKU8n
return p; AvPPsN0
} OJd/#KFm
}'*6 A
/** ujzfy
* if(p<=0) p=1 PQp =bX,
*
G:3szz
* @param p p{}4#+-<#H
*/ A $ ]s{`
publicvoid setP(int p){ Q'qX`K+@`
if(p <= 0) AVm+
1
p = 1; YN+vk}8 <
this.p = p; a{@}vZx>3
} |B^Mj57DO
tHAe
/** L^r & .N\
* 每页记录数量 ;s;3cC!
*/ xW]65iav
publicint getNum(){ a9UXg<4
return num; kIX1u<M~
} !JyY&D~`
Svb>s|D
/** tJ
2GSZ`
* if(num<1) num=1 .`Q^8|$-K
*/ tbWfm5$
publicvoid setNum(int num){ wJNm}Wf
if(num < 1) !-.GfI:q
num = 1; OQ-
Hn-H
this.num = num; hf^<lJh~=
} b+|3nc!
2:_6nWl
/** =#v? }JG
* 获得总页数 ![sXR
*/ wYg!H>5
publicint getPageNum(){ 6JDaZh"=K
return(count - 1) / num + 1; zh|9\lf
} *ziR &Fr!
,2^4"gIl
/** &w#!
* 获得本页的开始编号,为 (p-1)*num+1 c!_c, vwrn
*/ TN1pg
publicint getStart(){ N0.|Mb"?t
return(p - 1) * num + 1; E5$]0#jB
} fGO\f;P
^lAM /
/** TS#[[^!S
* @return Returns the results. nYFrp)DLK
*/ FY ms]bv
publicList<E> getResults(){ I# &r5Q
return results; ZZ7qSyBs?
} 7/
?QZN
MUAs(M;
public void setResults(List<E> results){ ,wwO0,"y7
this.results = results; kQ lU.J>^
}
fT|A^
UXs)$
public String toString(){ xC,x_:R`
StringBuilder buff = new StringBuilder xEp?|Q$
Dlq!:dF{&
(); KWZhCS?[(
buff.append("{"); 3iIy_nWC
buff.append("count:").append(count); )@X0'X<
buff.append(",p:").append(p); aL( hWE
buff.append(",nump:").append(num); ~/]]H;;^u
buff.append(",results:").append #3QPcoxa
qD4]7"9
(results); S0)JIrrHC
buff.append("}"); &CQO+Yr$l
return buff.toString(); lI 4tW=
} 2S{P(B
K5jt(7i
} PDuc;RG
@kqxN\DE
@Fb1D"!