Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 U@T"teGBA
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 7u73v+9qn:
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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 ?Dm={S6
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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 %/iD@2r
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分页支持类: |qTvy,U[
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java代码: bl yU53g
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package com.javaeye.common.util; D y+)s-8
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import java.util.List; 5,dKha
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publicclass PaginationSupport { I(m*%>
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publicfinalstaticint PAGESIZE = 30; +guCTGD:
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privateint pageSize = PAGESIZE; Kcl~cIh7 7
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privateList items; P! cfe@;<4
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privateint totalCount; f[1 s4Dp3-
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privateint[] indexes = newint[0]; R`
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privateint startIndex = 0; gpT~3c;l=
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public PaginationSupport(List items, int GY`mF1b
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totalCount){ ) KvGJo)("
setPageSize(PAGESIZE); ^O6eFD U
setTotalCount(totalCount); f?JP=j
setItems(items); mY=Q#nG
setStartIndex(0); )B*D\9\Z
} B)/L[ )S
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public PaginationSupport(List items, int (zr2b
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totalCount, int startIndex){ ~n=oPm$pR
setPageSize(PAGESIZE); '2z1$zst,#
setTotalCount(totalCount); ]A&pXAM
setItems(items); w%1-_;.aU6
setStartIndex(startIndex); ;~,)6UX7
} Y6 <.]H
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public PaginationSupport(List items, int *$]50 \W
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totalCount, int pageSize, int startIndex){ -{XDQ{z<%
setPageSize(pageSize); SPT?Tt
setTotalCount(totalCount); v#|yr<
setItems(items); =4[
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setStartIndex(startIndex); 6Vgxfic
} G\z5Ue*
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publicList getItems(){
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return items; h_HPmh5
} hnimd~E52k
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publicvoid setItems(List items){ 3a?|}zr4
this.items = items; \`0s %F:V}
} <v6W
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publicint getPageSize(){ 'gtcy
return pageSize; K&VMhMVb
} <A(Bq'eQM
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publicvoid setPageSize(int pageSize){ |It&1fz}
this.pageSize = pageSize; &+0?Xip{Z
} p9 G{Q
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publicint getTotalCount(){ J4x|Af p
return totalCount; K$l@0r ~k
} U.WXh(`%
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publicvoid setTotalCount(int totalCount){ 9#>nFs"H
if(totalCount > 0){ w^9< I]
this.totalCount = totalCount; ik](k"1{
int count = totalCount / ^xgqs $`7
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pageSize; S,EL=3},=
if(totalCount % pageSize > 0) t3AmXx
count++; on;>iKta9
indexes = newint[count]; &2Ef:RZF
for(int i = 0; i < count; i++){ $;&l{=e2)
indexes = pageSize * S['cX ~
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i; G`;\"9t5h
} mo+!79&
}else{ %LM6=nt
this.totalCount = 0; MsZx 0]
} ;%Px~g
} FUf.3@}
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publicint[] getIndexes(){ +$Y*1{hyOo
return indexes; bT6VxbNS
} 7l ,f
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publicvoid setIndexes(int[] indexes){ 61b*uoq0w?
this.indexes = indexes; PD^G$LT
} U{j4FlB
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publicint getStartIndex(){ w3 kkam"
return startIndex; RO|8NC<oj
} ,"KfZf;?
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publicvoid setStartIndex(int startIndex){ PU[<sr#,
if(totalCount <= 0) 7r50y>
this.startIndex = 0; 6)p8BUft
elseif(startIndex >= totalCount) {F2Rv
this.startIndex = indexes yXoNfsv
W9pY=9]p+
[indexes.length - 1]; IuT)?S7O*k
elseif(startIndex < 0) / Y od
this.startIndex = 0; 5eE\
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else{ Ep;i],}
this.startIndex = indexes tjwnFqI
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[startIndex / pageSize]; o[}Dj6e\t
} -KV,l
} y/ Bo4fM
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publicint getNextIndex(){ (9oo8&GG
int nextIndex = getStartIndex() + XI ;] c5
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pageSize; %#rtNDi
if(nextIndex >= totalCount) Ow*va\0
return getStartIndex(); 1Ml<>
else ?O+.
return nextIndex; \O4s0*gw
} {hJCn*m_
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publicint getPreviousIndex(){ ?P-O4
int previousIndex = getStartIndex() - )DhE~
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pageSize; i+qg*o$
if(previousIndex < 0) as]M%|/-I
return0; Wh..QVv
else wM4{\ f\
return previousIndex; K}cA%Y
} ]7cciob
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} g_IcF><F
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抽象业务类 i+mU(/l2{
java代码: /KWdIP#
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/** s|H7;.3gp
* Created on 2005-7-12 -%Vh-;Ie(
*/ kJJiDDL0;*
package com.javaeye.common.business; (kB
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import java.io.Serializable; 5I2 h(Td
import java.util.List; fcEm:jEZ*
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import org.hibernate.Criteria; ?_d>-NC
import org.hibernate.HibernateException; 8v2Wi.4T
import org.hibernate.Session; Bo8f52|
import org.hibernate.criterion.DetachedCriteria; .<>t2,Af
import org.hibernate.criterion.Projections; *5BVL_:~J
import fqbeO 9x
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org.springframework.orm.hibernate3.HibernateCallback; Jj[3rt?8
import O0z-jZ,])
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org.springframework.orm.hibernate3.support.HibernateDaoS \mGb|aF8
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upport; 75^*4[
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import com.javaeye.common.util.PaginationSupport; ]kmAN65c
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public abstract class AbstractManager extends ef{Hj[8
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HibernateDaoSupport { 3{co.+
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privateboolean cacheQueries = false; U&B(uk(2
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privateString queryCacheRegion; J+ :3==,
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publicvoid setCacheQueries(boolean |>j^$^l~
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cacheQueries){ YK8l#8K
this.cacheQueries = cacheQueries; 9m>L\&\_e
} u"v$[8
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publicvoid setQueryCacheRegion(String Om:Gun\%
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queryCacheRegion){ 5?>Q[a.Ne
this.queryCacheRegion = s!YX<V
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queryCacheRegion; jK6dI
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} 5C`Vno~v
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publicvoid save(finalObject entity){ ^v;8 (eF
getHibernateTemplate().save(entity); nrpbQ(zI*
} NODE`VFu
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publicvoid persist(finalObject entity){ tJd/uQJ
getHibernateTemplate().save(entity); :WH0=Bieh
} QB*AQ5-
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publicvoid update(finalObject entity){ u?g;fh6
getHibernateTemplate().update(entity); "$%&C%t
} =x^IBLHN
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publicvoid delete(finalObject entity){ O'~^wu.
getHibernateTemplate().delete(entity); I%{D5.du
} r)qow.+&
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publicObject load(finalClass entity, P]4u`&
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finalSerializable id){ zq^eL=%:
return getHibernateTemplate().load Rwmr [g
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(entity, id); x2]chN
} kf",/?s2Z
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publicObject get(finalClass entity, ]'i}}/}u2
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finalSerializable id){ #|l#
return getHibernateTemplate().get );z/
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(entity, id); g9gyx/'*
} [ 3SbWwg
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publicList findAll(finalClass entity){ g>f_'7F&
return getHibernateTemplate().find("from _H2%6t/V
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" + entity.getName()); xb(y15R\I
} qZ+^ND(I
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publicList findByNamedQuery(finalString ~c
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namedQuery){
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return getHibernateTemplate ?[Qxq34
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().findByNamedQuery(namedQuery); Nj4^G ~_
} 5l(NX
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publicList findByNamedQuery(finalString query, }W R?n
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finalObject parameter){ 4^BHJOvs
return getHibernateTemplate 1|\/2
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().findByNamedQuery(query, parameter); `zRm
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} L[:b\O/p,
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publicList findByNamedQuery(finalString query, 0j|JyS:}G
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finalObject[] parameters){ m:XMF)tW
return getHibernateTemplate +q3E>K9a
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().findByNamedQuery(query, parameters); 7~Md6.FtM
} '&$xLZ8
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publicList find(finalString query){ 5S?+03h~
return getHibernateTemplate().find U
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(query); | sio:QP
} [6Gb@jG
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publicList find(finalString query, finalObject #!X4\+)
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parameter){ 564)ha/^(
return getHibernateTemplate().find nE3'm[)
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(query, parameter); Pb^Mc <j
} +8AGs,
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public PaginationSupport findPageByCriteria qj5V<c;h%W
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(final DetachedCriteria detachedCriteria){ !h0#es\
return findPageByCriteria .UuCTH;6`
>)3[CU,
(detachedCriteria, PaginationSupport.PAGESIZE, 0); .:b|imgiv
} hkq[xgX
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public PaginationSupport findPageByCriteria $*`=sV!r
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(final DetachedCriteria detachedCriteria, finalint Xn'{g
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startIndex){ D^knN-nZ*
return findPageByCriteria !V6O~#
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(detachedCriteria, PaginationSupport.PAGESIZE, X;I;CZ={
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startIndex); (gv1f
} Xk_xTzJ
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public PaginationSupport findPageByCriteria j~eYq
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(final DetachedCriteria detachedCriteria, finalint .'q0*Pe
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pageSize, u2SnL$A7
finalint startIndex){ ,3t('SE
return(PaginationSupport) Q}a 1P8?S
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getHibernateTemplate().execute(new HibernateCallback(){ yE(> R(^
publicObject doInHibernate J3oj}M*
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(Session session)throws HibernateException { %8 )GuxG*
Criteria criteria = ^gwVh~j
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detachedCriteria.getExecutableCriteria(session); o!`.LL%
int totalCount = 8$:4~:]/
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((Integer) criteria.setProjection(Projections.rowCount >g]S"ku|
_y q"F#,*
()).uniqueResult()).intValue(); 'J (4arN
criteria.setProjection W2VH? -Gw
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(null); ef\Pu\'U
List items = M+X>!Os
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criteria.setFirstResult(startIndex).setMaxResults #<X+)B6t
xF'9`y^]!@
(pageSize).list(); 85rXm*Df
PaginationSupport ps = }LDH/#
u
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new PaginationSupport(items, totalCount, pageSize, Vd2bG4*=
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startIndex);
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return ps; .]+oE$,!
} >y C1X|d~t
}, true); b{|Ha3;w
} =,q,W$-
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public List findAllByCriteria(final <KF|QE
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DetachedCriteria detachedCriteria){ -iu7/4!j
return(List) getHibernateTemplate sW[8f
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().execute(new HibernateCallback(){ CzKU;~D=B
publicObject doInHibernate EQDsbG0x
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(Session session)throws HibernateException { -~O7.E(ok
Criteria criteria = pqmS
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detachedCriteria.getExecutableCriteria(session); ?\MvAG7Y
return criteria.list(); MA\"JAP/
} } 5~|h%
}, true); D"^4X'6
} vtyk\e)
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public int getCountByCriteria(final C~PrIM?
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DetachedCriteria detachedCriteria){ w]b3,b
Integer count = (Integer) .i[rd4MCK
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getHibernateTemplate().execute(new HibernateCallback(){ QiB^U^f
publicObject doInHibernate rQ -pD
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(Session session)throws HibernateException { kwRXNE(k]_
Criteria criteria = tbHU(#~
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detachedCriteria.getExecutableCriteria(session); xc[LbaBG
return QeP8Vl&e:
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criteria.setProjection(Projections.rowCount $\kqh$")
(q'w"q j
()).uniqueResult(); FB{4& ;
} 07WZ w1(;
}, true); pI2g\cH>
return count.intValue(); '\qd{mM\r
} &z[39Q{~
} =Nn&$h l
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用户在web层构造查询条件detachedCriteria,和可选的 Fy!uxT-\
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 <Z%iP{
ad^7t<a}<
PaginationSupport的实例ps。 dIiQ^M
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ps.getItems()得到已分页好的结果集 k,o|"9H
ps.getIndexes()得到分页索引的数组 ?3bUE\p
ps.getTotalCount()得到总结果数 b~?FV>gl
ps.getStartIndex()当前分页索引 !yAg!V
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ps.getNextIndex()下一页索引 Vy-N3L
ps.getPreviousIndex()上一页索引 $Lpt2:.((
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 e(7F| G*
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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 fD1J@57
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一下代码重构了。 3=w$1.B d
+*"u(7AV
我把原本我的做法也提供出来供大家讨论吧: iB#xUSkS
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首先,为了实现分页查询,我封装了一个Page类: ceN*wkGyB
java代码:
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/*Created on 2005-4-14*/ _l$V|
package org.flyware.util.page; @]r,cPx0Y
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/** 5B3S]@%
* @author Joa p!5oz2RK
* f0rM 4"1
*/ df_hmkyj
publicclass Page { UH=pQm^W
>`Xikn(
/** imply if the page has previous page */ nNNs3h(Ss
privateboolean hasPrePage; /wplP+w2
3!_X FV
/** imply if the page has next page */ 9PXG*r|D
privateboolean hasNextPage; -#Xo^-&
7x8/Vz@\
/** the number of every page */ aO:wedfl
privateint everyPage; 5yPw[
EY
m$^Wyk}
/** the total page number */ ,l-tLc
privateint totalPage; &AR@5M u
*x[ZN\$`Y
/** the number of current page */ z~b5K\/1B
privateint currentPage; WGwpryaya
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/** the begin index of the records by the current M*M,Z
s;!TB6b@
query */ \;&WF1d`ac
privateint beginIndex; ug]WIG7 S
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/** The default constructor */ :x"Q[079
public Page(){ a<%Ivqni
| Q0Wv8/
} fuRCM^U(
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/** construct the page by everyPage NDsF<2A4
* @param everyPage QD6<sw@]P
* */ u-v/`F2wN
public Page(int everyPage){ 4%k{vo5i
this.everyPage = everyPage; x-0O3IIE
} p6)Jzh_/
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/** The whole constructor */ Rr>nka)U
public Page(boolean hasPrePage, boolean hasNextPage, 0?@;zTE0
=$kSvCjP
[wp(s2=
int everyPage, int totalPage, MaMP7O|W
int currentPage, int beginIndex){ >;wh0dBe
this.hasPrePage = hasPrePage; )96tBA%u
this.hasNextPage = hasNextPage; d v8q&_
this.everyPage = everyPage; X*'i1)_h
this.totalPage = totalPage; ~w
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this.currentPage = currentPage; {,:yZ&(
this.beginIndex = beginIndex; `i~kW
} w|t}.u
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/** 8.`*O
* @return VD.wO%9?)
* Returns the beginIndex. l~mC$>f
*/ nF"NXYa
publicint getBeginIndex(){ qDlh6W?}k
return beginIndex; _bsAF^ ;
} ;W~H|M
q8m[ S4Q]g
/** 2!kb?
* @param beginIndex $?Dcp^
* The beginIndex to set. lf`" (:./
*/ c_~tCKAZ
publicvoid setBeginIndex(int beginIndex){ wZe>}1t
this.beginIndex = beginIndex; ]a=n(`l?
} s:/Wz39SY3
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/** A>9IE(C_
* @return #MyF 1E
* Returns the currentPage. b )(si/]\
*/ S UBrFsA
publicint getCurrentPage(){ qh~$AJ9sB
return currentPage; )B$Uo,1
} +T8h jOkC
52P^0<Wq
/** 2G&H[`
* @param currentPage ]39])ul
* The currentPage to set. KFhnv`a.0
*/ +*`>7m<^
publicvoid setCurrentPage(int currentPage){ #&sw%CD
this.currentPage = currentPage; $?*XPzZ
} /A82~
8+mu'RZ X
/** Yc`PK =!l
* @return O*lMIWx
* Returns the everyPage. Dzr(Fb
*/ 1$n!Lj=5
publicint getEveryPage(){ p)c"xaTP#F
return everyPage; .22}=z
} =`EVg>+^
k =
/** ,<O|#`?"@G
* @param everyPage Uqd2{fji=#
* The everyPage to set. :F.eyA|#@G
*/ g0M/Sv
publicvoid setEveryPage(int everyPage){ K)P].htw
this.everyPage = everyPage; 2#_i_j
} y{9<>28
z)fg>?AGr
/**
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* @return 7hAc6M$h;
* Returns the hasNextPage. l0BYv&tu
*/ ?'mi6jFFh
publicboolean getHasNextPage(){ Ou5,7Ne
return hasNextPage; &eFv~9
} evE$$# 6R
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/** @u1mC\G
* @param hasNextPage '-[?iF@l
* The hasNextPage to set. D8=a +!l-
*/ \w=*:Z
publicvoid setHasNextPage(boolean hasNextPage){ </li<1
this.hasNextPage = hasNextPage; pP*`b<|
} %&&;06GU}
v]U0@#/p
/** r!)jxIL\
* @return ^2eH0O!
* Returns the hasPrePage. ~IS3i'bh
*/ E-b3#\^:
publicboolean getHasPrePage(){ - %`iLu
return hasPrePage; !^IAn
} U,tWLX$@
-3|i5,f
/** JAS!eF
* @param hasPrePage <lf6gb
* The hasPrePage to set. &)F#cVB
*/ l>?k>NEpP
publicvoid setHasPrePage(boolean hasPrePage){ F:cenIaBF
this.hasPrePage = hasPrePage; {f[X)
} )" H r3
8BggK6X
/** wlS/(:02
* @return Returns the totalPage. 'Y38VOI%
* nm^HL|
*/ ':*H#}Br-#
publicint getTotalPage(){ \J'}CX*aQ
return totalPage; M0V<Ay\%O
} ).~
"
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/** inut'@=G/
* @param totalPage DT-VxF6 h
* The totalPage to set. X/5m}-6d]
*/ PR:k--)D
publicvoid setTotalPage(int totalPage){ .#[ 9q-
this.totalPage = totalPage; ?qh-#,O9B
} fBS a8D3}`
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} Jf YgZ\#
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e3I""D{)[=
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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 -/f$s1
=LW!$p
个PageUtil,负责对Page对象进行构造: ZW4f "
java代码: MAh1tYs4D
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@G5T8qwN
/*Created on 2005-4-14*/ e@D_0OZ
package org.flyware.util.page; hD6BP
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import org.apache.commons.logging.Log; [F-R*}&x
import org.apache.commons.logging.LogFactory; (r|m&/
8>KUx]AN
/** ?sN{U\
* @author Joa 'a#lBzu\b
* o'2eSm0H
*/ mU5Ox4>&9
publicclass PageUtil { fi?4!h
c^}y9% 4c
privatestaticfinal Log logger = LogFactory.getLog n!)$e;l
abo=v<mR
(PageUtil.class); \|=6<ZY:
ON2o^-%=
/** +x]/W|5
* Use the origin page to create a new page e]4$H.dP
* @param page B+W7zv
* @param totalRecords 'ZbWr*bo
* @return erH,EE^-x<
*/ z33UER"
publicstatic Page createPage(Page page, int y:'Ns$+
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totalRecords){ Pn,I^Ej .
return createPage(page.getEveryPage(), gd;!1GNi]
>Hf{Mx{<
page.getCurrentPage(), totalRecords); 3FBL CD3
} U,g8:M
xHK
U1 _"D+XB
/** z\ZnxZ@
* the basic page utils not including exception |ADf~-AY
D$l!lRu8+L
handler u*C*O4f>OC
* @param everyPage EGXvz)y
* @param currentPage 9c@M(U@Yh
* @param totalRecords K_YrdA)6
* @return page s"jvO>[
*/ }e\"VhAl/
publicstatic Page createPage(int everyPage, int t^01@ejM+
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currentPage, int totalRecords){ E ;Z(v
everyPage = getEveryPage(everyPage); A8-[EBkK
currentPage = getCurrentPage(currentPage); Wga2).j6
int beginIndex = getBeginIndex(everyPage, r8 9o
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currentPage); 8pnD6Lp>
int totalPage = getTotalPage(everyPage, 6 f*:;
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totalRecords); C.?^] Y
boolean hasNextPage = hasNextPage(currentPage, NBk0P*SI
s#^0[ Rt
totalPage); w)7y{ya$
boolean hasPrePage = hasPrePage(currentPage); ;@Zuet
. 1kB8&}
returnnew Page(hasPrePage, hasNextPage, Mt.Cj;h@^[
everyPage, totalPage, B $u/n
currentPage, )+N{D=YM
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beginIndex); MT!Y!*-5
} "z9C@T
}ny7LQ
privatestaticint getEveryPage(int everyPage){ (WHgB0{
return everyPage == 0 ? 10 : everyPage; f1vD{M;
} /9br &s$B
r D@*xMW
privatestaticint getCurrentPage(int currentPage){ 30vxOkS
return currentPage == 0 ? 1 : currentPage; d5^^h<'
} p8'$@:M\
k2
Ju*W&
privatestaticint getBeginIndex(int everyPage, int v>keZZOs
Bz/ba *
currentPage){ '&cH,yc;b
return(currentPage - 1) * everyPage; {py%-W
} V1'otQH2l
SZH`-xb!+5
privatestaticint getTotalPage(int everyPage, int sJL Oz>
J8)l ,J"
totalRecords){ ;`oK5
int totalPage = 0; 'I>USl3 hI
#1-WiweO
if(totalRecords % everyPage == 0) /3M8;>@u
totalPage = totalRecords / everyPage; %*Ex2we&
else >B6*`3v
totalPage = totalRecords / everyPage + 1 ; \
ku5%y
4'z)J1M
return totalPage; i.^ytbH
} _M%>Q m
1)k+v17]f5
privatestaticboolean hasPrePage(int currentPage){ Il
[~
return currentPage == 1 ? false : true; Cn/WNCzst&
} Z3JUYEAS
Q0(6n8i
privatestaticboolean hasNextPage(int currentPage, ,]EhDW6
X$5
int totalPage){ :.5l
return currentPage == totalPage || totalPage == m%6VwV7U
%M`48TW)
0 ? false : true; \2kLj2!
} 9)7$U QY
'4uu@?!dVk
t.8r~2(?
} :&wb+tV
@dv8 F
"v
jRjeL'"G
b$klm6nMvm
&:l-;7d
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。 ]JkEf?;.
o6vnl
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 }. &ellNQ
~yJ 2@2I
做法如下: )I&.6l!#
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 _Gq6xv\b1
zx%WV@O9
的信息,和一个结果集List: *|S6iSn9R!
java代码: +4-T_m/W/
-8^qtB
\Wfw\x0.
/*Created on 2005-6-13*/ @?<[//1
package com.adt.bo; KFbB}oId
YTyrX
import java.util.List; _f0AV;S:vd
YTa
g|If
import org.flyware.util.page.Page; *#YZm>h
?C[?dg{n
/** -g~+9/;n
* @author Joa {]+t<
*/ ]^C 8Oh<
publicclass Result { bqED5;d'#
! $$>D"
private Page page; s A,bR|
W#bYz{s.
private List content; ZHK>0>;
U=bx30brh%
/** LJ[zF~4#
* The default constructor Oin9lg-jR
*/ o^/
#i`)
public Result(){ F_*']:p
super(); gko=5|c,@
} bKpy?5&>
G[mqLI{q
/** #r9+thyC
* The constructor using fields x{:U$[_
* zz*PAYl.
* @param page \!\:p/f
* @param content KdCrI@^
*/ (%fQhQ
public Result(Page page, List content){ .rK0C)
this.page = page; -{0Pq.v
this.content = content; {<ShUN
} ~3 :VM_
DDr\Kv)k(
/** tL OGj?/r
* @return Returns the content. D;!sH?J@+
*/ 4fKvB@O@.
publicList getContent(){ YcA. Bn|as
return content; Z^V;B _
} ]W?cy
U(f@zGV
/** f![] :L
* @return Returns the page. z[f]mU
*/ ?V2P]|
public Page getPage(){ J,Ki2'=
return page; 4;L|Ua
} xq;>||B
1;/SXJ s
/** =Q9^|& 6
* @param content wG)e8,#
* The content to set. =CFjG)L
*/ 4dbX!0u1l
public void setContent(List content){ J6CSu7Voa
this.content = content; XdJD"|,h
} 1#x5
o2n
M1eh4IVE?
/** h^(U:M=A
* @param page ]izHn; +
* The page to set. -dovk?'Gj
*/ c$1u
publicvoid setPage(Page page){ Ou1kSG|kM
this.page = page; 2@MpWj4
} j(y<oxh
} 8d*S9p,/
h~Ir=JV
6H0kY/quL|
-F/)-s6#!'
Ei:m@}g
2. 编写业务逻辑接口,并实现它(UserManager, X}'rPz\Lu
0i}.l\
UserManagerImpl) 0 @#Jz#?
java代码: fP<==DK
(tA[] ne2
)F hbN@3
/*Created on 2005-7-15*/ 1CJ1-]S(3
package com.adt.service; qf K
gNZ
ozsd6&z5l
import net.sf.hibernate.HibernateException; "d-vs t5
(;g/wb:
import org.flyware.util.page.Page; ;LgMi5dN
w)<.v+u.Y
import com.adt.bo.Result; Fdl0V:<
)PR`irw
/** ,8DC9yM,
* @author Joa b:9"nALgC
*/ uLv
publicinterface UserManager { WMKxGZg"
;ZJ. 7t'
public Result listUser(Page page)throws ,MHK|8!
sz%]rN6$
HibernateException; nd\$Y
s-6$C
} xX%{i0E
}`Wo(E}O
k_1;YOBF
^VzhjKSu
ymrnu-p o
java代码: b!-=L&V
43=)akJi
OtAAzc!dQ
/*Created on 2005-7-15*/ ??Urm[Y.Z
package com.adt.service.impl; i%i s<'
b$Ei>%'/";
import java.util.List; I<W<;A
K
d#(eGe
import net.sf.hibernate.HibernateException; 0WZd $
1.,KN:qe
import org.flyware.util.page.Page; xA;)02
import org.flyware.util.page.PageUtil; +i /4G.=*
D1ik*mDA=
import com.adt.bo.Result; PXl%"O%d
import com.adt.dao.UserDAO; s{c|J#s
import com.adt.exception.ObjectNotFoundException; 6%9 kc+
9
import com.adt.service.UserManager;
[g@Uc
RHd no C
/** 1uyd+*/(xP
* @author Joa am'K$s
*/ 1#|lt\T
publicclass UserManagerImpl implements UserManager { ~md06"AYJ
6 %` h2Z
private UserDAO userDAO; 0}`
-<(
^\S~rW.3_
/** mWP&N#vwh
* @param userDAO The userDAO to set. Y#P!<Q>}
*/ Q"!GdKM
publicvoid setUserDAO(UserDAO userDAO){ 0e:j=kd)NH
this.userDAO = userDAO; J`; 9Z
} 1JOoICjB
aU.!+e%_
/* (non-Javadoc) 0XC3O 8q
* @see com.adt.service.UserManager#listUser re4z>O*
(B*,|D[J@i
(org.flyware.util.page.Page) zII^Ny8D
*/ [tC=P&<
public Result listUser(Page page)throws ))X"bFP!3
3 l
j^I
HibernateException, ObjectNotFoundException { ZBH^0
int totalRecords = userDAO.getUserCount(); M4
}))
if(totalRecords == 0) SpIiMu(
throw new ObjectNotFoundException t,A=B(W
=RM]/O9
("userNotExist"); oZL# *Z(h
page = PageUtil.createPage(page, totalRecords); d&ff1(j(
List users = userDAO.getUserByPage(page); {XC[Ia6jtL
returnnew Result(page, users); 3_&s'sG5
} fU.z_T[@
}:s.m8LC5n
} ZBQ @S
qd'Z|'j
&:}WfY!hX
M`*
BS
|v#rSVx
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 7?vj+1;
m*lcIa
询,接下来编写UserDAO的代码: +'VYqu/
3. UserDAO 和 UserDAOImpl: h>Z`&
java代码: iJKGzHvS
#oR@!?
^8dCFw.rU
/*Created on 2005-7-15*/ ,nV4%Aa
package com.adt.dao; >$a;+v
\zDs3Hp
import java.util.List; ^q|W@uG-(
e)XnS '
import org.flyware.util.page.Page; &2ty++gC
<LJb,l"
import net.sf.hibernate.HibernateException; nuA
0%K
Wn?),=WQ{
/** )4,U
* @author Joa cT;Zz5
*/ P%!=Rj^ 2m
publicinterface UserDAO extends BaseDAO { Otf{)f
Nz;\PS
publicList getUserByName(String name)throws VZ
7(6?W
Tgbq4xR(
HibernateException; &zP>pQr`#
$Fy>N>,E(
publicint getUserCount()throws HibernateException; (zk/>Ou
5/CF_v
publicList getUserByPage(Page page)throws LPca+o|f
J`{o`>
HibernateException; O,NVhU7,
(I35i!F+tY
} YPCitGBl
B`jq"[w]-
D`KaIqLz
?a1pO#{Dg
{.y_{yWo
java代码: VC%.u.< F
Bx5kqHp^1
}Fox
/*Created on 2005-7-15*/ )%lPKp4]
package com.adt.dao.impl; $2-_j)+
i` ay9J8N
import java.util.List; Wu8^Z Z{
Mq'm
TM
import org.flyware.util.page.Page; \wK4bvUrX
~03MH'
import net.sf.hibernate.HibernateException; ?zbW z=nq
import net.sf.hibernate.Query; Tf?`_jL
yO*
import com.adt.dao.UserDAO; f$vTD ak
t*u#4I1
/** {];-b0MS~
* @author Joa a#& ( i
*/ vbZ!NO!H
public class UserDAOImpl extends BaseDAOHibernateImpl Xkg
>7S@3,C3ke
implements UserDAO { LhM$!o?W
)?c,&
/* (non-Javadoc) S kB*w'k
* @see com.adt.dao.UserDAO#getUserByName (oG.A
49c-`[d
L
(java.lang.String) -|>T?
t'K
*/ m7u`r(&
publicList getUserByName(String name)throws vUOl@UQ5
U~;tk@
HibernateException { a(D=ZKbVU
String querySentence = "FROM user in class lBAu@M
a6 0rJ#GD
com.adt.po.User WHERE user.name=:name"; sf->8
Query query = getSession().createQuery 3eXIo=
{IaDZ/XS6
(querySentence); bovAFdHW
query.setParameter("name", name); r\Kcg~D>
return query.list(); m8e()8lZ3
} S6a\KtVa
V/kndV[j
/* (non-Javadoc) {*[(j^OE
* @see com.adt.dao.UserDAO#getUserCount() (/,l0
*/ 7]ysvSM
publicint getUserCount()throws HibernateException { gZ7R^]
k
int count = 0; x\f~Gtt7Y
String querySentence = "SELECT count(*) FROM nJ
xO.wWE
AX<f$%iqD
user in class com.adt.po.User"; 6Io}3}3
Query query = getSession().createQuery oOU_
Nay
a#;;0R $
(querySentence); FO:L+&hr?>
count = ((Integer)query.iterate().next tp>YsQy]8
x\8|A
()).intValue(); |iUC\F=-
return count; &b}g.)RI
} UeLO `Ug0;
&ah%^Z4um
/* (non-Javadoc) $D#h, `
* @see com.adt.dao.UserDAO#getUserByPage nReld
:#T
p\lR1
(org.flyware.util.page.Page) j-W$)c3X
*/ ^jwzCo-
publicList getUserByPage(Page page)throws ipbhjK$
VN!nef
HibernateException { 3Z=yCec]
String querySentence = "FROM user in class 10*Tk 8
, 6X;YY
com.adt.po.User"; X )tH23
Query query = getSession().createQuery %HoD)OJe
$5)#L$!,]
(querySentence); ['.])
query.setFirstResult(page.getBeginIndex()) n9}BT^4 v
.setMaxResults(page.getEveryPage()); Vb\g49\o/
return query.list(); 4^l 9d
} Sq ]gU
jgIG";:Q
} cOX )+53
{L%J DJ
YYYF a
,#3Aaw
LkS tU)
至此,一个完整的分页程序完成。前台的只需要调用 Mh-"B([Z
Yr_B(n
userManager.listUser(page)即可得到一个Page对象和结果集对象 B=& [Z2
nLz;L r!
的综合体,而传入的参数page对象则可以由前台传入,如果用 !~~KM?g
KYm8|]'g
webwork,甚至可以直接在配置文件中指定。 N{HAWB{
>j hcSvM6
下面给出一个webwork调用示例: Uq#2~0n>
java代码: oOpEpQ}}q
_.; PLq~0
zMbFh_dcq
/*Created on 2005-6-17*/ qm!oJL
package com.adt.action.user; ;7:} iKU
XKky-LeJ
import java.util.List; z:f&k}(
s_NY#MPz[
import org.apache.commons.logging.Log; h@$SJe(hl
import org.apache.commons.logging.LogFactory; M> WWP3
import org.flyware.util.page.Page; ?DUim1KG
<|_>r`@%l
import com.adt.bo.Result; `D[O\ VE
import com.adt.service.UserService; ZL<X*l2
import com.opensymphony.xwork.Action; Tty'ysH
XYWyxx5`
/** zU&Iy_Ke.
* @author Joa q=88*Y
*/ azv173XZ
publicclass ListUser implementsAction{ /e>%yq<9B
#U`AK9rP_g
privatestaticfinal Log logger = LogFactory.getLog piM4grg
\
#Pg`0xiV
(ListUser.class); TS6xF?
DfAF-Yhut
private UserService userService; )\u%XFPhS
>B0AJW/u
private Page page; K^fs#7
M@{?#MkS%
privateList users; R%RbC!P
N~$>| gn
/* #9|&;C5',!
* (non-Javadoc) qK.(wFx
* {FvFah
* @see com.opensymphony.xwork.Action#execute() pmB
{b
*/ Bp7p X
publicString execute()throwsException{ #[=kQ&
Result result = userService.listUser(page); &B(z**+9
page = result.getPage(); n5d8^c! 2
users = result.getContent(); Mn
,hmIz
return SUCCESS; b
VEJ
} 8S8qj"s
I9qZE=i
/** doL-G?8B
* @return Returns the page. ,K,st+s|
*/ 5m~9Vl-&
public Page getPage(){ \bd KLcKI,
return page; {4 Yxh8
} 7e+C5W*9b
rlKR
<4H
/** |-V:#1wR.]
* @return Returns the users. (y]Z *p:EW
*/ Uwkxc
publicList getUsers(){ fPD.np}
return users; W_M#Gi/AL
} ;B 8Q,.t>x
Fqw4XR_`~
/** ^ l#6Es
* @param page A*DN/lG
* The page to set. 14'\@xJMM
*/ ."ZG0Zg
publicvoid setPage(Page page){ U2YY
this.page = page; ra'/~^9
} W2X`%Tx0
eAW)|=2
/** op`9(=DJ]
* @param users B$rhsK%
* The users to set. nlB'@r
*/ B<EqzP*#
publicvoid setUsers(List users){ b, a7XANsh
this.users = users; ZXs,TaU
} GPLop/6
YtvDayR>
/** s\mA3t
* @param userService j?u1\<m
* The userService to set. =7}1NeC`
*/ `W1uU=c
publicvoid setUserService(UserService userService){ 15jQ87)
this.userService = userService; +&7V@
} sPQjB[
} H 0+-$s;f
RI8*'~ix]
[4#HuO@h
!$l<'K$
gN<7(F
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, 1_{ e*=/y
;MGm,F,o
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 p+~Imf-Jk
z$^wCd:
么只需要: aR3jeB,=x
java代码: 2
)o2d^^
^&&Wv'7XQ
@>(JC]HtR
<?xml version="1.0"?> 5nib<B%<V
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork 2fkyz
=SmU;t>t/
1.0//EN" "http://www.opensymphony.com/xwork/xwork- r rfJs
<k8WnA ~Fl
1.0.dtd"> a^LckHPI>
NpGi3>5
<xwork> I N3-ZNx
90uXJyW;d
<package name="user" extends="webwork- j_,/U^Ws|f
GpTZp#~;
interceptors"> #akJhy@m$
.BJoY
<P*
<!-- The default interceptor stack name `=pA;R9
+mBS&FK
--> `EgX#
<default-interceptor-ref 8Kl&_-l{b
(7<G1$:z=
name="myDefaultWebStack"/> 4r_*: $g
}=f\WWJf0
<action name="listUser" FWeUZI+
V?yQm4
class="com.adt.action.user.ListUser"> KsIHJr7-
<param r{?qvl!q
:4[>]&:u3
name="page.everyPage">10</param> ~Qif-|[V
<result "Ia.$,k9
{Pe&J2
+
name="success">/user/user_list.jsp</result> 0=
bXL!]
</action> ;\}dQsX
(D[~Z!
</package> HABUf^~-
Ln6emXqw
</xwork> 4xT /8>v2|
=/j!S|P
OH`zeI,[*
.!^OmT,u
3%r/w7Fc
R#Yj%$E1
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 +fM8
19[o XyFI
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。 5h Sd,#:
;uc3_J]
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 d]K8*a%[-
H(Wiy@cJn
)$1j"mV
/C'_-U?
euV!U}Xr
我写的一个用于分页的类,用了泛型了,hoho POc<XLZB
ze9n}oN
java代码: `K@N\VM
Iao?9,NL9O
m4uh<;C~
package com.intokr.util; q},,[t
_IEbRVpb
import java.util.List; BZTj>yd
!S7?:MJ?p\
/** 6NyUGGRq
* 用于分页的类<br> _7u&.l<;
* 可以用于传递查询的结果也可以用于传送查询的参数<br> +B8oW3v# )
* GNwFB)?j
* @version 0.01 fUis_?!
* @author cheng F@ pf._c
*/ ^; U}HAY
public class Paginator<E> { t{s>B]i^_w
privateint count = 0; // 总记录数 =^ Ws/k
privateint p = 1; // 页编号 Fsq)co
privateint num = 20; // 每页的记录数 -f:PgBj
privateList<E> results = null; // 结果 ('uUf!h?\
v`'Iew }
/** ">8oF.A^
* 结果总数 <
fe.
*/ @o}J )
publicint getCount(){ =d~pr:.F
return count; o,_F;ZhE
} s/>0gu]A8
&.yX41R
publicvoid setCount(int count){ 1PWi~1q{Q
this.count = count; zmuRn4Nv
} e50xcf1u
I_?R(V[9
/** I:al[V2g
* 本结果所在的页码,从1开始 Q>\DM'{:4
* Mw+
l>92
* @return Returns the pageNo. jC>mDnX
*/ I3Z\]BI
publicint getP(){ E)p[^1WC
return p; _~>WAm<
} 9&kPcFX B
(<H@W/0$
/**
f/.f08
* if(p<=0) p=1 KdTWi;mV2-
* NYxL7 :9
* @param p >*^SQ{9
*/ wJgH15oB
publicvoid setP(int p){ DV({! [EP
if(p <= 0) *cXi*7|=
p = 1; g^=Ruh+
this.p = p; 5YI6$ZdQ
} weGsjy(b]N
|hDN$By
/** W^;4t3eQf
* 每页记录数量 x
FvKjO)
*/ QQ=tiW
publicint getNum(){ vQoZk,
return num; w&hCt