Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 l]@&D#3ZM
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 ~3UQ|j
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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 #,S0HDDHn
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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 Tu@8}C
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分页支持类: mYxuA0/k
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java代码: -mC0+}h
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package com.javaeye.common.util; s4G|_==
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import java.util.List; ~1cnE:x;V
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publicclass PaginationSupport { R#xCkl -
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publicfinalstaticint PAGESIZE = 30; `kOD[*
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privateint pageSize = PAGESIZE; 'HT7_$?*
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privateList items; rJPb 3F
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privateint totalCount; 6^%UU
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privateint[] indexes = newint[0]; @WJgWJm
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privateint startIndex = 0; /4t j3B,
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public PaginationSupport(List items, int (H)2s Y
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totalCount){ |w_7_J2
setPageSize(PAGESIZE); WEFlV4/
setTotalCount(totalCount); 0="%Y^N
setItems(items); &Q+Ln,(&L
setStartIndex(0); z|=}1;(.
} \x)n>{3C
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public PaginationSupport(List items, int M>DaQ`b
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totalCount, int startIndex){ 6726ac{xz
setPageSize(PAGESIZE); cS>e?
setTotalCount(totalCount); zEs>b(5u
setItems(items); 3l)h yVf&
setStartIndex(startIndex); ipQLK{]t
} 8S>&WR%jH]
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public PaginationSupport(List items, int `n$I]_}/%
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totalCount, int pageSize, int startIndex){ 7+]=-
setPageSize(pageSize); `^bgUmJ~
setTotalCount(totalCount); 6Pnk5ps }h
setItems(items); D|@/yDQ
setStartIndex(startIndex); JmPHAUd
} xm%Um\Pb7
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publicList getItems(){ e"/;7:J5\
return items; ] x\-$~E
} eK.e|z|
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publicvoid setItems(List items){ ElS 9?Q+
this.items = items; r~N"ere26
} 3mYiQ2
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publicint getPageSize(){ 5V5%/FUm
return pageSize; TftHwe):V
} L~(_x"uXd
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publicvoid setPageSize(int pageSize){ +# GQ,
this.pageSize = pageSize; =g/{%;
} k9$K}
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publicint getTotalCount(){ <.pU,T/
return totalCount; eAX
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} jZh';M8"
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publicvoid setTotalCount(int totalCount){ 0|2%vh >J
if(totalCount > 0){ XpmS{nb
this.totalCount = totalCount; bA=
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int count = totalCount / G:<`moKgL
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pageSize; i-bJS6
if(totalCount % pageSize > 0) @Gx.q&H
count++; 1c<=A!"{
indexes = newint[count]; ZX5 xF<os8
for(int i = 0; i < count; i++){ cs T2B[f9D
indexes = pageSize * $rz=6h
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} qY~`8
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}else{ =0^Ruh
this.totalCount = 0; H,+I2tEs
} H2Z1TIh
} ]?3un!o3o
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publicint[] getIndexes(){ &C_'p {G
return indexes; AFc$%\s4
} 0TN;86Mo
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publicvoid setIndexes(int[] indexes){ &8%e\W\K:/
this.indexes = indexes; Y]{
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} %6L^2
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publicint getStartIndex(){ Hu.t 3:w
return startIndex; ]4h92\\965
} ~n[xtWO0
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publicvoid setStartIndex(int startIndex){ +x_Rfk$fb
if(totalCount <= 0) {.Z}5K
this.startIndex = 0; 2R=DB`3
elseif(startIndex >= totalCount) bhkUKxd
this.startIndex = indexes [F*.\
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[indexes.length - 1]; A3B56K
elseif(startIndex < 0) q-]`CW]n
this.startIndex = 0; *H?!;u=8
else{ ,Y|^^?'j
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this.startIndex = indexes Y2d;E.DH8
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[startIndex / pageSize]; uHAT#\m:
} 'd+NVj{C
} _^el\
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publicint getNextIndex(){ OR}c)|1
int nextIndex = getStartIndex() + '~ ,p[
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pageSize; ]l'Y'z,}
if(nextIndex >= totalCount) G
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return getStartIndex(); l5\"9 ,<
else UNPezHaz
return nextIndex; w QNxL5B
} Bn61AFy`
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publicint getPreviousIndex(){ ms!r ef4`+
int previousIndex = getStartIndex() - e*bH0'; q
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pageSize; jy giG&H
if(previousIndex < 0) Qtbbb3m;
return0; fO0(Z
else OfctoPP _0
return previousIndex; usEwm,b)
} ([-|}
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} wY~&Q}U
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抽象业务类 JJ{9U(`_y6
java代码: (FJ9-K0b{n
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/** C?i >.t
* Created on 2005-7-12 _~q?_'kx
*/ <Q?a=4
package com.javaeye.common.business; p/U+0f
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import java.io.Serializable; U Z|HJ8_
import java.util.List; dbOdq
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import org.hibernate.Criteria; 'ihhoW8
import org.hibernate.HibernateException; Qu}W/j|3
import org.hibernate.Session; 1Wm)rXW[x
import org.hibernate.criterion.DetachedCriteria; ^s@8VAwi
import org.hibernate.criterion.Projections; qf=1?=l291
import O~59FuL
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org.springframework.orm.hibernate3.HibernateCallback; Tszp3,]f
import z]2]XTmWs
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org.springframework.orm.hibernate3.support.HibernateDaoS 5v?;PX
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upport; ;=<-5;rI
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import com.javaeye.common.util.PaginationSupport; q^A+<d
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public abstract class AbstractManager extends 6_d.Yfbq
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HibernateDaoSupport { jS+AGE?5e
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privateboolean cacheQueries = false; KN?6;G{
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privateString queryCacheRegion; a)S+8uU
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publicvoid setCacheQueries(boolean [74F6Qp
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cacheQueries){ T"&)&"W*U
this.cacheQueries = cacheQueries; ^Ve<>b
} E@-KGsdhK
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publicvoid setQueryCacheRegion(String K
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queryCacheRegion){ j:,NE(DF
this.queryCacheRegion = !!4Qj
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queryCacheRegion; E[O<S B
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} zCOgBT~p
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publicvoid save(finalObject entity){ YKbaf(K)9
getHibernateTemplate().save(entity); f{"8g"[[)(
} $b<6y/"
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publicvoid persist(finalObject entity){ fx@j?*Qb
getHibernateTemplate().save(entity); p_UlK8rb
} uA$<\fnz
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publicvoid update(finalObject entity){ `u.t[
getHibernateTemplate().update(entity); =)E,8L
} f8SL3+v
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publicvoid delete(finalObject entity){ f+|$&p%
getHibernateTemplate().delete(entity); Qc[3Fq,f
} 8E8N6
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publicObject load(finalClass entity, &AlJ "N|
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finalSerializable id){ {tThy#
return getHibernateTemplate().load 52.>+GC
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(entity, id); U,+[5sbo
} P
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publicObject get(finalClass entity, `Pw*_2
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finalSerializable id){ #-8\JEn
return getHibernateTemplate().get /
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(entity, id); 4J?t_)
} $2<d<Um~z
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publicList findAll(finalClass entity){ Qj3a_p$)P
return getHibernateTemplate().find("from etd&..]J
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" + entity.getName()); rJa$9B*^
} "+zCS|
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publicList findByNamedQuery(finalString 4QIE8f
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namedQuery){ ltkI}h,e
return getHibernateTemplate S}f?.7
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().findByNamedQuery(namedQuery); 2 o#,kGd
} >6oOZbUY0
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publicList findByNamedQuery(finalString query, I+ es8
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finalObject parameter){ TRZRYm"
return getHibernateTemplate f50L,4,
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().findByNamedQuery(query, parameter); yQ3OL#
} &QG6!`fK}3
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publicList findByNamedQuery(finalString query, f30Pi1/h=c
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finalObject[] parameters){ 4CQ"8k(S"
return getHibernateTemplate AW#<i_Ybf
Z4){
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().findByNamedQuery(query, parameters); x!_<z''
} 4lqH8l.
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publicList find(finalString query){ RNPbH.
return getHibernateTemplate().find N$xtHtz8"
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(query); __[xD\ES
} PyA&ZkX>
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publicList find(finalString query, finalObject 15$4&=O
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parameter){ T6pLoaKu
return getHibernateTemplate().find ~Ph\Sbp
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(query, parameter); )HD`O~M>
} v|ox!0:#
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public PaginationSupport findPageByCriteria oo=#XZkk
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(final DetachedCriteria detachedCriteria){ W5/0`[4
return findPageByCriteria (_r EAEo
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); +3i7D
} 'a^{=+
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public PaginationSupport findPageByCriteria uY<
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(final DetachedCriteria detachedCriteria, finalint )2DQ>cm
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startIndex){ \([WH!7
return findPageByCriteria r-kMLw/)
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(detachedCriteria, PaginationSupport.PAGESIZE, >/<:Q &
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startIndex); hI pKJ&hm
} 9_fePS|Z4
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public PaginationSupport findPageByCriteria aS|wpm)K>8
^). )
(final DetachedCriteria detachedCriteria, finalint D;Gq)]O
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pageSize, Dml*T(WM>
finalint startIndex){ {FN;'Uc
return(PaginationSupport) iqhOi|!
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getHibernateTemplate().execute(new HibernateCallback(){ 0)Rw|(Fpo]
publicObject doInHibernate '!Gs>T+
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(Session session)throws HibernateException { F8e<}v&7R
Criteria criteria = xt4)Ya
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detachedCriteria.getExecutableCriteria(session); w62=06`@
int totalCount = 2X-l{n;>
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((Integer) criteria.setProjection(Projections.rowCount ED$DSz)x
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()).uniqueResult()).intValue(); ~#}Dx
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criteria.setProjection <DH*~tLp2
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(null); xjdw'v+qZo
List items = G6K
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criteria.setFirstResult(startIndex).setMaxResults K?#]("De6
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(pageSize).list(); k:A|'NK~
PaginationSupport ps = I\\QS.2
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new PaginationSupport(items, totalCount, pageSize, >EXb|vw
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startIndex); %lr|xX
return ps; -{|`H[nmD
} %;z((3F
}, true); %HtuR2#ca
} 6Ggs JU
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public List findAllByCriteria(final ,pq{& A
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DetachedCriteria detachedCriteria){ N0n^L|(R
return(List) getHibernateTemplate d~ng6pA
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().execute(new HibernateCallback(){ g"Qh]:
publicObject doInHibernate Oajv^H,Em
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(Session session)throws HibernateException { BbJkdt7
Criteria criteria = }tST)=M`
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detachedCriteria.getExecutableCriteria(session); ;52'}%5
return criteria.list(); V'Qn sI
} $e\N+~KNCy
}, true); lS{r=y_0.
} kvsA]tK.
#
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public int getCountByCriteria(final ,D80/2U^
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DetachedCriteria detachedCriteria){ i}TwOy<4s
Integer count = (Integer) xPmN},i'R$
}0=<6\+:`
getHibernateTemplate().execute(new HibernateCallback(){ lm'Zy"~::
publicObject doInHibernate Q
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(Session session)throws HibernateException { ;n#%G^!H
Criteria criteria = Aj"7q
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detachedCriteria.getExecutableCriteria(session); FE5Q?*Ea
return N4^5rrkL
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criteria.setProjection(Projections.rowCount ,*,sw:=2
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()).uniqueResult(); wpPn}[a
} `T!#@&+
}, true); 'bW5Fr>W
return count.intValue(); ]]iO- }
} qFRdg V>8
} 1H4fJ3-
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用户在web层构造查询条件detachedCriteria,和可选的 EU`T6M
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 A{,n;;
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PaginationSupport的实例ps。 rjojG59U>
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ps.getItems()得到已分页好的结果集 iL?iz?+.%@
ps.getIndexes()得到分页索引的数组 6`nR5 fh
ps.getTotalCount()得到总结果数 #ch
ps.getStartIndex()当前分页索引 Jj"HpK>[
ps.getNextIndex()下一页索引 hol<dB
ps.getPreviousIndex()上一页索引 eG]a zt
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 #n})X,ip2
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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 )r!e2zc=Q
(6xDu.u?A
一下代码重构了。 iQ`]ms+
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我把原本我的做法也提供出来供大家讨论吧: Y_H/3?b%
RtF8A5ys
首先,为了实现分页查询,我封装了一个Page类: -Wjh* *
java代码: 4~u9B/v
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/*Created on 2005-4-14*/ ,ECAan/@
package org.flyware.util.page; ubGs/Vzye
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/** Gbb\h
* @author Joa INNAYQ
* l)@:T|)c
*/ hLuJWjCV
publicclass Page { yFeeG3n3
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/** imply if the page has previous page */ !EFBI+?&
privateboolean hasPrePage; @phN|;?
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/** imply if the page has next page */ wJIB$3OT
privateboolean hasNextPage; Ph)|j&]
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/** the number of every page */ QrS$P09=\
privateint everyPage; #8?^C]*{0
};SV!'9s?~
/** the total page number */ vl5){@
privateint totalPage; 9) ea.Gu
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/** the number of current page */ k=uZ=tUft*
privateint currentPage; ^5)_wUf
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/** the begin index of the records by the current P4%>k6X
f-+.;`H)T
query */ /yK"t<p
privateint beginIndex; YX;nMyD?~
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/** The default constructor */ #]zhZW4
public Page(){ W8*
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} 0zV 4`y
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/** construct the page by everyPage wgZrrq/W|
* @param everyPage $^$ECDOTB
* */ HDj$"pS
public Page(int everyPage){ Tk+DPp^
this.everyPage = everyPage; $c9=mjwH
} #WEq-0L
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/** The whole constructor */ x7gjG"V
public Page(boolean hasPrePage, boolean hasNextPage, tR O IBq|
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int everyPage, int totalPage, k /^g*
int currentPage, int beginIndex){ j |td,82.
this.hasPrePage = hasPrePage; 5B|,S1b
this.hasNextPage = hasNextPage; \3j)>u,r
this.everyPage = everyPage; 3Uo]>BG
this.totalPage = totalPage; ZYKd
this.currentPage = currentPage; (6-y+LG
this.beginIndex = beginIndex; Lh!z>IWjOG
} 5mIXyg 0:
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/** vzy!3Hiw
* @return <(uTst
* Returns the beginIndex. R-C5*$
*/ ,RN|d0dE
publicint getBeginIndex(){ E0jUewG
return beginIndex; A^vvST%7
} EE9vk*[@C
K P6PQgc
/** LaT8l?q q
* @param beginIndex ^Y<M~K972
* The beginIndex to set. ?%;B`2 nDR
*/ cuMc*i$w!
publicvoid setBeginIndex(int beginIndex){ &CO|Y(+
this.beginIndex = beginIndex; <i7agEdZD
} ` U#Po_hq
TK %<a/
/** %^U"Spv;
* @return fp-m.d:|
* Returns the currentPage. I4ctxMVP
*/ Wx k;g
publicint getCurrentPage(){ *#GDi'0
return currentPage; ex0oAt^
} &q L<C
Z fqQ{_
/** L6 kZ2-6
* @param currentPage PC0HH
* The currentPage to set. O(Td:Zdp
*/ OaNc9c"
publicvoid setCurrentPage(int currentPage){ <vLdBfw&N
this.currentPage = currentPage; D{W
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} /Mx.:.A&$
@Q3, bj
/** %xpd(&)n
* @return sSy$(%
* Returns the everyPage. \N yr=<c
*/ NkoofhZ
publicint getEveryPage(){ W/a,.M
return everyPage; F`3^wHw^
} +i4P,Lp
lT3|D?sF
/** *LEu=3lp%>
* @param everyPage bkkSIl+Q
* The everyPage to set. *bU% @O
*/ p4y6R4kyT
publicvoid setEveryPage(int everyPage){ ]p\u$VY9
this.everyPage = everyPage; ZGzc"r(r:#
} Vp\80D&
oL)lyUVT
/** =kF?_K N
* @return lh~<s2[R2
* Returns the hasNextPage. LVoyA/F
*/ $)l2G;&
publicboolean getHasNextPage(){ >mew"0Q
return hasNextPage; q$|0)}
} L1rAT
7\f{'KL
/** gINwvzW{
* @param hasNextPage %B0w~[!4}
* The hasNextPage to set. 1O23"o5=
*/ s9G)Bd 8
publicvoid setHasNextPage(boolean hasNextPage){ C~{xL>I
this.hasNextPage = hasNextPage; K,G,di
} R~!\-6%_
/ Z1Wy-Z
/** 7x%S](m%
* @return ,}n=Z
* Returns the hasPrePage. 48:liR
*/ \+G.]|" Y
publicboolean getHasPrePage(){ K_Z+]]$#
return hasPrePage; Z~:/#?/
} @|E;}:?u
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/** R
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* @param hasPrePage Kyu@>9Ok
* The hasPrePage to set. An/>05|
*/ 9}.,2JE
publicvoid setHasPrePage(boolean hasPrePage){ U{HyxZ|q<
this.hasPrePage = hasPrePage; -*r [
} HE@-uh
$]nVr(OZ_
/** avmcGyL
* @return Returns the totalPage. kHGeCJe\{
* +jv}\Jt
*/ G2=F8kL
publicint getTotalPage(){ PIgGXNo
return totalPage; 3,%nkW
} U
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H]VsOr
/** f 5mY;z"
* @param totalPage fYb KmB
* The totalPage to set. >).@Nb;e
*/ $^]
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publicvoid setTotalPage(int totalPage){ VtD@&N
this.totalPage = totalPage; tN[St
} K<RmaXZ
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} Nz3zsP$
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M\9at\$
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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 b=V)?"e-
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个PageUtil,负责对Page对象进行构造: +GRxHuW,
java代码: K3a>^g
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/*Created on 2005-4-14*/ XCW+ pUX
package org.flyware.util.page; "9)1K!tH
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import org.apache.commons.logging.Log; bta0?O
#
import org.apache.commons.logging.LogFactory; UEN YJ*tnP
u4go*#
/** JqL<$mSep
* @author Joa ]lymY _ >
* ],!\IqO
*/ j@%K*Gb`
publicclass PageUtil { A"Tc^Ij
p
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privatestaticfinal Log logger = LogFactory.getLog t^`<*H
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(PageUtil.class); 5Xp$yX =
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/** w g$D@E7
* Use the origin page to create a new page ac2}3$u
* @param page N;e;4,_ n
* @param totalRecords OJnPP>
* @return [6Uud iw
*/ QWU5-p9e8
publicstatic Page createPage(Page page, int bv .EM
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totalRecords){ emGV]A%nss
return createPage(page.getEveryPage(), ;:v]NZtc
$ iX^p4v
page.getCurrentPage(), totalRecords); oc!biE`u
} OI)&vQ5k
Q3 K;kS
/** Rh wt<
* the basic page utils not including exception d)`nxnbMeM
\9dz&H
handler n,CD4Nv
* @param everyPage _Ym&UY.u#
* @param currentPage *O"%tp6
* @param totalRecords ^G]KE8
* @return page M>`?m
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*/ Hj}g1"RA
publicstatic Page createPage(int everyPage, int MsN2A6|33
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currentPage, int totalRecords){ .F{}~K]
everyPage = getEveryPage(everyPage); 9OrA9r
currentPage = getCurrentPage(currentPage); FE$M[^1_
int beginIndex = getBeginIndex(everyPage, 'DaNR`9
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currentPage); 9'L1KQ
int totalPage = getTotalPage(everyPage, ^N*pIVLC
T{5M1r
totalRecords); 31
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boolean hasNextPage = hasNextPage(currentPage, eukX#0/^
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totalPage); mafAC73
boolean hasPrePage = hasPrePage(currentPage); fJSV)\e0
fS;m+ D!j@
returnnew Page(hasPrePage, hasNextPage, ?^e*UJNM
everyPage, totalPage, e
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currentPage, ;XD>$t@
7)ES!C
beginIndex); :X1`wBu
} -ucz+{
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privatestaticint getEveryPage(int everyPage){ {,nd_3"Vq
return everyPage == 0 ? 10 : everyPage; @LwVmR |{
} %8bFQNd
`Gy>tD.#V-
privatestaticint getCurrentPage(int currentPage){ XnNOj>!
return currentPage == 0 ? 1 : currentPage; 7LyV`6{70
} cOj +}Hz58
qiwQUm{
privatestaticint getBeginIndex(int everyPage, int $G^H7|PzdC
BP7<^`i&
currentPage){ yKX:Z4I/
return(currentPage - 1) * everyPage; \kua9bK
} $S"zxEJJ Y
%j
9vX$Hj
privatestaticint getTotalPage(int everyPage, int 7;$L&X
bUipp\[aV
totalRecords){ VC_3 ll]vr
int totalPage = 0; ;&7qw69k
=6"hj,[Q
if(totalRecords % everyPage == 0) ynOc~TN
totalPage = totalRecords / everyPage; )VSGqYr#
else _zVbqRHlw
totalPage = totalRecords / everyPage + 1 ; g*"J10hyP
bOnukbJ
return totalPage; j,gM+4V^
} DcFV^8O&
.q'FSEkMJ
privatestaticboolean hasPrePage(int currentPage){ uMq\];7I
return currentPage == 1 ? false : true; 6 ^6uK
} {kY`X[fvZ
z~A(IQO
privatestaticboolean hasNextPage(int currentPage, _3FMQY(
p!rGPyGC
int totalPage){ Q
xj|lr
return currentPage == totalPage || totalPage == 6i?kkULBS
`"bRjC"f]
0 ? false : true; B4M'Er{v
} EP%
M8
Q>+_W2~]
=:0IHyB#0
} s]V{}bY`
$yxIE}
CO6XIgTe
zL[U;
@N:3`[oB
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。 U`vt/#j
1
:` !mCW`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 9Rt(G_'
ua. 6?W)
做法如下: H~1?MAX
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 ./5MsHfbxt
sB*h`vs0T
的信息,和一个结果集List: JqH.QnKcv
java代码: u0$5Fd&X
Hf E;$
;Vtpq3
/*Created on 2005-6-13*/ S+E3;' H
package com.adt.bo; hGaYQgGq
_tg3%X]
import java.util.List; vr]dRStr
6b1 Uj<
import org.flyware.util.page.Page; k+>p!1
m<VL19o>R
/** B+e~k?O] 1
* @author Joa xX67bswG
*/ l<+,(E=
publicclass Result { <P
Z\qE*+y
_ZvX" {y~
private Page page; EWvid4QEi
9DocId.
private List content; 7C6BZ$(
%%-Tjw o
/** 9"l%tq_
* The default constructor nqw*oLFQ
*/ Zq6ebj
public Result(){ @rDv
(W
super(); {UjIxV(J
} N'1 [t
,'@ISCK^
/** ?)ZLxLV::
* The constructor using fields ,\">o vV33
* kv`3Y0R-"
* @param page R|^t~h-
* @param content BtDgv.;GH
*/ HoQ(1e$G-
public Result(Page page, List content){ zJym`NF
this.page = page; ?eZ"UGZg'
this.content = content; boHm1hPKS
} 8C4@V[sm`
B\~3p4S
/** 085 ^!AZ
* @return Returns the content. m~\m"zJ4
*/ ieK'<%dxF
publicList getContent(){ ]&%X(jWyn
return content; pz z`4VS:
} SZ1pf#w!
_[6+FdS],
/** FV<^q|K/(]
* @return Returns the page. l[OQo|_
*/ k1
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public Page getPage(){ i2 Iu2
return page; sZ(Q4)r
} <
oG\)!O
3jQ$72_
/** Tlv|To
* @param content MZ#2WP)F
* The content to set. [@71
*/ |x~ei_x7.p
public void setContent(List content){ LB 5EGw
this.content = content; UmHb-uk ;
} Sr-^faL
doUqUak
/** XcW3IO
* @param page Op)R3qt{
* The page to set. o3`gx
*/ P)
0=@{(
publicvoid setPage(Page page){ (:hmp"S
this.page = page; KLM^O$=
} F_
lj>;}a5
} U8 @*I>vA
tw^.(m5d
gl4
f9Ff
)e$-B]>7z
~<Qxw>S#
2. 编写业务逻辑接口,并实现它(UserManager, EwJn1Mvq
qQ\hUii
UserManagerImpl) }z%/6`7)|
java代码: TEy.zzt
hQrsZv:Q
]0nC;|]@Lx
/*Created on 2005-7-15*/ H5rNLfw
'
package com.adt.service; C3
c|@7FU
h3ZL0Fi*
import net.sf.hibernate.HibernateException; G?X,Y\Lp
,}$x'8v
import org.flyware.util.page.Page; 5Ddyb%
`Y9}5p
import com.adt.bo.Result; Y@xeyMzE
9(\N+
/** I;PO$T
* @author Joa <.]& FPJ
*/ GoGgw]h>x
publicinterface UserManager { N1zrfn-VU
LWR&(p.%
public Result listUser(Page page)throws FKTP0e7=9
$zH0$aOx
HibernateException; 2G*#Czr"
s%re>)=|
} *" +cP!
rb4g<f|
iK23`@&%_
Lr]Hvd
Jywz27j
java代码: \^Q)`Lqp:g
&^<T/PiR
!c' ;L'
/*Created on 2005-7-15*/ Hm[!R:HW,S
package com.adt.service.impl; 3^Q U4
1T^L) %&p_
import java.util.List; " ~hj B
gG?*Fi
import net.sf.hibernate.HibernateException; Or~6t}f
:l[Q
import org.flyware.util.page.Page; nqW:P$
import org.flyware.util.page.PageUtil; im%3*bv-
2n,73$s
import com.adt.bo.Result; 833t0Ml1A/
import com.adt.dao.UserDAO; "+C\f)
import com.adt.exception.ObjectNotFoundException; y^fU_L?p
import com.adt.service.UserManager; sX?7`n1U
c7N9X 3A
/** SQ.Wj?W)
* @author Joa Dy'l]vN$
*/ qt;Tfuo
publicclass UserManagerImpl implements UserManager { J #5o
s: .XF|e{
private UserDAO userDAO; |1 6v4 R
;'+cT.cmH
/** z-E4-\a
* @param userDAO The userDAO to set. ^vz@d+\Kd
*/ Z-V%lRQ=b
publicvoid setUserDAO(UserDAO userDAO){ LR.+CxQ
this.userDAO = userDAO; u 9TlXn
} -C]a2
r\D8_S_
/* (non-Javadoc) M)RQIl5
* @see com.adt.service.UserManager#listUser Q2PwO;E.`C
S}I=i>QB
(org.flyware.util.page.Page) .OUE'5e p
*/ )eyxAg
public Result listUser(Page page)throws >gl <$LQ?X
t9l7
% +y
HibernateException, ObjectNotFoundException { VAzJclB
int totalRecords = userDAO.getUserCount(); u{d`
if(totalRecords == 0) (pg9cM]NA
throw new ObjectNotFoundException =l9#/G#R
CT`X~y10
("userNotExist"); 32/P(-
page = PageUtil.createPage(page, totalRecords); cW%O-
List users = userDAO.getUserByPage(page); jg/<"/E
returnnew Result(page, users); .k(_j.v
} md
s\~l73
!d)i6W?
} ?5gpk1
EF~PM
h}_q
{<n)zLy
N/=3Bs0y-
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 1r4/McB
tYa*%|!v
询,接下来编写UserDAO的代码: 1i2O]e!
3. UserDAO 和 UserDAOImpl: jgIzB1H
java代码: 3S?+G)qKo
%tLq&tyeY
Jp0.h8i
/*Created on 2005-7-15*/ jXR+>=_
package com.adt.dao; <rF
7mBL#T2
import java.util.List; _
RYZyw
K@lV P!z
import org.flyware.util.page.Page; JR)rp3o-
xnOlV
import net.sf.hibernate.HibernateException; [J
Xrj{
9m!fW|4
/** tsD^8~
t|h
* @author Joa 55\mQ|.Jn
*/ .@V>p6MV
publicinterface UserDAO extends BaseDAO { xb\:H@92
EUqG"h5#A{
publicList getUserByName(String name)throws z`SkKn0f
Y
j&5Xjl>4
HibernateException; \:7EKzQ
//|Vj | =
publicint getUserCount()throws HibernateException; Hq$|j,&?
2T9Z{v
publicList getUserByPage(Page page)throws ^Quy64M
RJD3o_("K
HibernateException; U4JN,`p{
] fB{
} _{%H*PxTn=
K(2s%
e+TNG &_
f'S"F
N5DS-gv
java代码: b.&YUg[#
{'(8<n57
cO9Aw !
/*Created on 2005-7-15*/ 2hP8ZfvIR
package com.adt.dao.impl; .VT,,0
6npwu5!
import java.util.List; ":ycyN@g
79_MP
import org.flyware.util.page.Page; Viw3 /K
=KLYR UW
import net.sf.hibernate.HibernateException; Dl{Pd`D
import net.sf.hibernate.Query; ,d#4Ib
cALs;)z
import com.adt.dao.UserDAO; AbB>ZT>hR
+fN0>@s
/** KMZ`Wn=
* @author Joa
0saEcJ-
*/ v]~[~\|a
public class UserDAOImpl extends BaseDAOHibernateImpl [qB=OxH?
@$]h[
implements UserDAO { S8l+WF4q
f`e.c_n(
/* (non-Javadoc) >Mn.|:DF]&
* @see com.adt.dao.UserDAO#getUserByName R0[Gfq9M=
oLoa71Q}
(java.lang.String) Z/x~:u_
*/ bkTj
Q
publicList getUserByName(String name)throws ojri~erJE?
>B0S5:S$W
HibernateException { ??PpHBJ')
String querySentence = "FROM user in class it$~uP |
65v'/m!ys
com.adt.po.User WHERE user.name=:name"; ~WSC6Bh@9
Query query = getSession().createQuery $ }53f'QjW
al/~
(querySentence); c@`P{6
query.setParameter("name", name); Wj&s5;2a
return query.list(); 2ip~qZNw><
} 9}N*(PI
zPe .
/* (non-Javadoc) >\ W" 3.
* @see com.adt.dao.UserDAO#getUserCount() 0dW1I|jR
*/ vq}V0-
<
publicint getUserCount()throws HibernateException { J']W7!p
int count = 0; 5>
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String querySentence = "SELECT count(*) FROM E2MpMR
aH_&=/-Tz
user in class com.adt.po.User"; X9 R-GT
Query query = getSession().createQuery ~$B,K]
Iu8=[F>
(querySentence); P1<;:!8'
count = ((Integer)query.iterate().next .JE7vPv%!
H UjmJu6f{
()).intValue(); rYl37.QE
return count; !wgj$5Rw.
} )'JSu=Ej
/.r($Sg^
/* (non-Javadoc) B}W^s;h
* @see com.adt.dao.UserDAO#getUserByPage 1K>4i. X
_[x(p6Xp
(org.flyware.util.page.Page) 8'y|cF%U
*/ 8Bhng;jX
publicList getUserByPage(Page page)throws u8*0r{kOH
r"+
WUU
HibernateException { kcle|B
String querySentence = "FROM user in class ;1KhUf;&F
3;A1[E6K
com.adt.po.User"; vzL>ZBeZ
Query query = getSession().createQuery kQ +
]zO]*d=m
(querySentence); g!$
"CX%8
query.setFirstResult(page.getBeginIndex()) {R K#W~h
.setMaxResults(page.getEveryPage()); rTH@PDk>)
return query.list(); _R]h]<TQ
} bWqGypq4
QO8/?^d
}
[7bY(
+=R:n^r^,
?NL2|8
\vI_%su1N
XP'KgTF
至此,一个完整的分页程序完成。前台的只需要调用 ]n+:lsiV
UJb7v:^
userManager.listUser(page)即可得到一个Page对象和结果集对象 }~7>S5
$hL0/T-m
的综合体,而传入的参数page对象则可以由前台传入,如果用 8]O|$8'"
<^=k~7m
webwork,甚至可以直接在配置文件中指定。 L@/+u+j0
>,DR{A2hSB
下面给出一个webwork调用示例: +"<f22cS1
java代码: | c;S'36
,GK>|gNsb
m>iuy:ti
/*Created on 2005-6-17*/ ]SQ_*$`
package com.adt.action.user; @t_<oOI2
kz#DBh!&
import java.util.List; !n7?w@2a'
/F\7_
import org.apache.commons.logging.Log; p'H5yg3h
import org.apache.commons.logging.LogFactory; 8w{V[@QLn
import org.flyware.util.page.Page; xe5>)\18-
rJAY7/u
import com.adt.bo.Result; "PX~Yc
import com.adt.service.UserService; 9`xq3EL2T
import com.opensymphony.xwork.Action; eN/Jb;W
@-hy:th#
/** h.67]U7m
* @author Joa 4EOu)#
*/ k2xjcrg
publicclass ListUser implementsAction{ _%t w#cM
`q F:rQ
privatestaticfinal Log logger = LogFactory.getLog lU\|F5O@#
qB8<(vBP+
(ListUser.class); ^!A{ 4NV
}Iu 6]?|'
private UserService userService; }RD,JgmV
6:e0?R^aD"
private Page page; NWKD:{
rP*?a~<
privateList users; * 6uiOtH
Fr3Q"(
/* qWWy}5SOm
* (non-Javadoc) #oHHKl=M
* UOa{J|k>h
* @see com.opensymphony.xwork.Action#execute() Q} /
:
*/ v'|Dj^3[
publicString execute()throwsException{ er 97&5
Result result = userService.listUser(page); b7\nCRY
page = result.getPage(); 3c6<JW
users = result.getContent(); le*pd+> j
return SUCCESS; W] RxRdY6[
} -q-%)f
k(T/ydrw
/** _mcD*V
* @return Returns the page. 9;:Lf
*/ OrzDr
public Page getPage(){ r>
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return page; 0n5N-b?G-@
} `AYHCn
T'w=v-(J
/** $[IuEdc/
* @return Returns the users. `>K;S!z
*/ T;I a;<mfE
publicList getUsers(){ CnJO]0Op3
return users; d~qDQ6!
} m,-:(82
vh((HS-)
/** K !`t EW[
* @param page :[,n`0lH
* The page to set. Cfa?LgSz
*/ KpSHf9!&[
publicvoid setPage(Page page){ Y@Ty_j~
this.page = page; [7$.)}Q-
} N'TL &]
2LXy$[)7
/** ny{|{a
* @param users VNF@)!l
* The users to set. uZi]$/ic
*/ )bqO}_B
publicvoid setUsers(List users){ y6;A4p>
this.users = users; 7v#sr<
} BsRxD9r
'r3I/qg*m
/** {G_ZEo#x8,
* @param userService )
_"`{2
* The userService to set. \
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*/ XD9lox
publicvoid setUserService(UserService userService){ )fv0H&g
this.userService = userService; l\a 0 k4
} 2}t2k>
} TN(1oJ:
7)z^*;x
m\[r6t]V
|6$6Za]:
HjLY\.S
上面的代码似乎看不出什么地方设置了page的相关初值,事实上, L=
hPu#&/
@MTm8E6au
可以通过配置文件来进行配置,例如,我想每页显示10条记录,那 gTm[ <Y
!\2Xr{f
么只需要: .XTBy/(0
java代码: ?~hC.5
JuS#p5E #
<t&0[l
<?xml version="1.0"?> )y_MI
r
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork Fd9ypZs
d_]zX;_
1.0//EN" "http://www.opensymphony.com/xwork/xwork- RoT}L#!!
eVn]/.d
1.0.dtd"> Bk*AO?3p
=rGjOb3+
<xwork> vEk
jd#
SVo:%mX
<package name="user" extends="webwork- U)o(}:5xF
*#w+*ywVZH
interceptors"> C8%q?.nH=
w>J|416
<!-- The default interceptor stack name GeD^-.^
|-%[Z
--> ;i@,TU
<default-interceptor-ref *6?h,Dt L
GBVw6+(c
name="myDefaultWebStack"/> w/#k.YE
LW
8LD|@
<action name="listUser" C0Z
mv
~A(fn:d
class="com.adt.action.user.ListUser"> >S,yqKp37~
<param +"'cSAK
n3-5`Jti
name="page.everyPage">10</param> p<: bPw
<result :'|%~&J
F$F,I,$ "
name="success">/user/user_list.jsp</result> ?I6 !m~
</action> ZkSlztL)Tr
4f:B 2x{
</package> 3o5aB1
sEm-Td+A5
</xwork> mfc\w'
1/:WA:]1,
y yW;VKN
9(V12gn+lk
}4b
4<Sm_h
Mj|\LF +
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 Lk9X>`b#B
w9Bbvr6
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。 SvLI%>B=9
7j| ^ZuI+
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 * G!C 'w\$
6 GqR]KD
y@Z@ eK3
$aDAD4mmm
^{lcj
我写的一个用于分页的类,用了泛型了,hoho Ii FeO
Fuq ;4UcbL
java代码: V(3^ev/
?S9? ?y/
uxLT*,
package com.intokr.util; #eadkj#;
xkV(E!O
import java.util.List; ~-ZquJ-
?Dm={S6
/** 4+I @
* 用于分页的类<br> p8,Rr{
* 可以用于传递查询的结果也可以用于传送查询的参数<br> w+($=n~
* ;5Spdi4w
* @version 0.01 uj;tmK>;
* @author cheng cBZ$$$v\#
*/ G'<:O(Imu
public class Paginator<E> { Mtq\xF,/+
privateint count = 0; // 总记录数 1k"<T7K
privateint p = 1; // 页编号 8T-/G9u
privateint num = 20; // 每页的记录数 cuzU*QW"g
privateList<E> results = null; // 结果 '-c
*S]: r
/6",#B}%b
/** -|V1A[
* 结果总数 imw,Nb
*/ @
>_v/U'
publicint getCount(){ p?rh+0wgX
return count; a4aM.o
} Wg{ 9X#|
cip5 -Z@8
publicvoid setCount(int count){ W cOyOv
this.count = count; 1seWR"
} GYH{_Fq
j}u b
/** b$FK}D5
* 本结果所在的页码,从1开始 6)=`&>9
* [>--U)/
* @return Returns the pageNo. e7tp4M9!%
*/ ^IW5c>;|
publicint getP(){ k6eh$*!
return p; <OgwA$abl%
} dmA#v:$1
PzF>yG[
/** JX!z,X?r4
* if(p<=0) p=1 &FrUj>i
* 1?I_fA}
* @param p YF8;s4
*/ A; _Zw[
publicvoid setP(int p){ -So$f-y
if(p <= 0) y[`>,?ns5
p = 1; N$ oQK(
this.p = p; BN7]u5\7
} Mbm'cM&}
!#&`1cYX
/** t?Ku6Z'
* 每页记录数量 Dxvizd>VU
*/ /tdRUX
publicint getNum(){ (}B3df
return num; @=<B8VPJd
} >G9YYt~
fM/~k>wl
/** L0\~K~q
* if(num<1) num=1 /aV;EkyO,
*/ 5]f6YlJZ
publicvoid setNum(int num){ ?kM2/a"{G
if(num < 1) 5nV IC3N+1
num = 1; M:M"7>:
this.num = num; Tfq7<<0$N
} +h]~m_O
PPAcEXsIu
/** Kj53"eW
* 获得总页数 1VKu3
*/ "%(SLQOyy
publicint getPageNum(){ 9QP- ~V{$
return(count - 1) / num + 1; :_8Nf1B+T
} v`r![QpYf
-#Bk
/** u_HCXpP!Q
* 获得本页的开始编号,为 (p-1)*num+1 @ /.w%
*/ +-r ~-b s
publicint getStart(){ ctOBV
return(p - 1) * num + 1; J5!-<oJ/
} y
g:&cIr,
O2qy[]km
/** 6n A/LW\x
* @return Returns the results. P(%^J6[>
*/ fK|P144
publicList<E> getResults(){ 2WK c;?
return results; +R8G*2
} {nPiIPH
v\lKY*@f
public void setResults(List<E> results){ )TfX}
this.results = results; 70<{tjyc
} ,Dab(
t
i&!_
public String toString(){ "T@9#7Obu
StringBuilder buff = new StringBuilder 9^+E$V1@
K+\2cf?bU
(); xs6kr
buff.append("{"); eC3 ~| G_O
buff.append("count:").append(count); G\z5Ue*
buff.append(",p:").append(p); 8kLHQ0pmu
buff.append(",nump:").append(num); QXu[<V
buff.append(",results:").append -K (>uV!?
w2SN=X~#
(results); }U'VVPh_
buff.append("}"); OF} ."a
return buff.toString(); %At.nlss
} RkZyqt
@+
cJE4uL<
} d`UK mj
r$:hiE@
fHODS9HQ