Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 lw.4O^
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 *r
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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 B1EI'<S
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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 Rmq8lU
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分页支持类: kIm)Um
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java代码:
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package com.javaeye.common.util; l5> H\
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import java.util.List; H`js1b1n
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publicclass PaginationSupport { 6#,VnS)`q
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publicfinalstaticint PAGESIZE = 30; E3pnu.;U:_
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privateint pageSize = PAGESIZE; (<= e?
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privateList items; j k%MP6
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privateint totalCount; $VWeo#b
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privateint[] indexes = newint[0]; VtNY~
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privateint startIndex = 0; kRCuc}:SB
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public PaginationSupport(List items, int C*;g!~{
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totalCount){
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setPageSize(PAGESIZE); + _=&7
setTotalCount(totalCount); $ekB+
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setItems(items); Lo'P;Sb4<}
setStartIndex(0); EcBJ-j6d
} Y9b|lP7!
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public PaginationSupport(List items, int ^E)Kse.>
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totalCount, int startIndex){ E%R^
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setPageSize(PAGESIZE); >~;MQDU5*Y
setTotalCount(totalCount); X8F@U ^@
setItems(items); 5t`:=@u
setStartIndex(startIndex); Pj4WWK X
} -&PiD
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public PaginationSupport(List items, int h0YIPB
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totalCount, int pageSize, int startIndex){ c:
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setPageSize(pageSize); `$IuN*
setTotalCount(totalCount); `m6>r9:
setItems(items); 2>l
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setStartIndex(startIndex); ~$#"'Tl4J
} (dOC ^i
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publicList getItems(){ `yjHLg
return items; 9y BENvq
} 6m#V=4e*
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publicvoid setItems(List items){ xc%\%8C}
this.items = items; I3;{II
} E7A psi4]
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publicint getPageSize(){ Y{6vW-z_<
return pageSize; zTDB]z!A
} Hzr<i4Y=w9
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publicvoid setPageSize(int pageSize){ %SKp<>;9
this.pageSize = pageSize; Uu~7+oaQ
} <h(KIY9T
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publicint getTotalCount(){ P8tpbdZE-
return totalCount; l+6y$2QR
} %9,:
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publicvoid setTotalCount(int totalCount){ 9(;5!q,Gsg
if(totalCount > 0){ 08J[9a0[
this.totalCount = totalCount; }?"}R<F|M,
int count = totalCount / ]*I:N
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pageSize; #;9I3,@/Y
if(totalCount % pageSize > 0) ?2hS<qXX
count++; E kb9=/
indexes = newint[count]; ~H[
for(int i = 0; i < count; i++){ _ZM$&6EC
indexes = pageSize * {Y>5 [gp
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} 6jv_j[[
}else{ d~bZOy
this.totalCount = 0; XLEEd?Vct9
} ~r<@`[-L
} @Q!Jzw#B
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publicint[] getIndexes(){ MAhJ>qe8
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return indexes; k[TVu5R
} ;7id![KI4
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publicvoid setIndexes(int[] indexes){ ?gknJ:
this.indexes = indexes; Gm,vLs9H$T
} }2WscxL
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publicint getStartIndex(){ 3AKT>Wy =
return startIndex; 'r&az BO
} G,tJ\xMw8
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publicvoid setStartIndex(int startIndex){
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if(totalCount <= 0) r57&F`{
this.startIndex = 0; 1&zvf4
elseif(startIndex >= totalCount) cT2&nZ
this.startIndex = indexes )gOVnA/M
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[indexes.length - 1]; bve_*7CEM
elseif(startIndex < 0) 4*k>M+o/C4
this.startIndex = 0; @ |bN[X L
else{ 4(
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this.startIndex = indexes / z<7gd~oU
^$8@B]*
[startIndex / pageSize];
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}
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} pbfIO47ZC
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publicint getNextIndex(){ [I*)H7pt}
int nextIndex = getStartIndex() + w %4SNR
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pageSize; gYeKeW3)
if(nextIndex >= totalCount) ?q^o|Y/
return getStartIndex(); K|i:tHF]@
else V=$pXpro%
return nextIndex; hv)>HU&
} 9+:SS1_
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publicint getPreviousIndex(){ kJQH{n+)R
int previousIndex = getStartIndex() - x)35}mi){L
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pageSize; 7a$K@iWU
if(previousIndex < 0) vbt0 G-%Z
return0; o#"U8N%r
else d=`a-R0
return previousIndex; Q6Ay$*y=D
} / //
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} UB5CvM28
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抽象业务类 (/mR
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java代码: m:6^yfS
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/** JfOBZQ
* Created on 2005-7-12 a&^HvXO(>(
*/ ro& /
package com.javaeye.common.business; a+HGlj 2>
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import java.io.Serializable; ^sF/-/ {?U
import java.util.List; {l
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import org.hibernate.Criteria; q8m{zSr
import org.hibernate.HibernateException; WGmXq.
import org.hibernate.Session; (vR9vOpJ
import org.hibernate.criterion.DetachedCriteria; r\PO?1
import org.hibernate.criterion.Projections; ZVelKI8>
import :P2{^0$
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org.springframework.orm.hibernate3.HibernateCallback; f|v5itO2
import COc,
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org.springframework.orm.hibernate3.support.HibernateDaoS 5dvP~sw
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upport; J-UqH3({Z,
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import com.javaeye.common.util.PaginationSupport; lU\v8!Ji
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public abstract class AbstractManager extends Ub,5~I+`
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HibernateDaoSupport { n 3eLIA{
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privateboolean cacheQueries = false; mm
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privateString queryCacheRegion; (]@yDb4
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publicvoid setCacheQueries(boolean ;b`kN;s
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cacheQueries){ nF5\iV
this.cacheQueries = cacheQueries; HZawB25{
} Y5ZBP?P
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publicvoid setQueryCacheRegion(String g[c_rty
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queryCacheRegion){ 7DZZdH$Fm
this.queryCacheRegion = YHp]O+c
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queryCacheRegion; ]lqe,>
} (v,g=BS,
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publicvoid save(finalObject entity){ c]/X
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getHibernateTemplate().save(entity); B*@0l:
} S4Q
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publicvoid persist(finalObject entity){ Hk 0RT%PK
getHibernateTemplate().save(entity); {3* Ne /
} r`\6+ Ntb.
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publicvoid update(finalObject entity){ Ajm
getHibernateTemplate().update(entity); oypF0?!m
}
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publicvoid delete(finalObject entity){ Q{o ]^tN
getHibernateTemplate().delete(entity); Z[G[.\0
} =h>jo&=Wad
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publicObject load(finalClass entity, 7~qyz]KkE
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finalSerializable id){ {9XN\v=$"*
return getHibernateTemplate().load ?APCDZ^
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(entity, id); >^~W'etX|
} 9 gc0Ri[4m
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publicObject get(finalClass entity, adn2&7H
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finalSerializable id){ fzJ^`
return getHibernateTemplate().get 0: Nw8J
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(entity, id); >c@jl
} adtgNwg
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publicList findAll(finalClass entity){ M,vCAZ
return getHibernateTemplate().find("from ce<88dL
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" + entity.getName()); ZA7b;{o [
} W_L;^5Y;m
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publicList findByNamedQuery(finalString W|L#Q/
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namedQuery){ 3kavzB[
return getHibernateTemplate v05$"Ig
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().findByNamedQuery(namedQuery); PVi0|
} qQwf#&
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publicList findByNamedQuery(finalString query, S=a>rnF
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finalObject parameter){ BC)1FxsGf
return getHibernateTemplate bMB@${i}
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().findByNamedQuery(query, parameter); `PtfPt<{
} Kut@z>SK
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publicList findByNamedQuery(finalString query, f~?kx41dq
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finalObject[] parameters){ T2}X~A
return getHibernateTemplate =<X4LO)C
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().findByNamedQuery(query, parameters); }E^k*S
} !PfdY&.)
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publicList find(finalString query){ Ce:w^P+
return getHibernateTemplate().find $#-O^0D
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(query); avY<~-44B
} .naSK`J,`
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publicList find(finalString query, finalObject k !V@Q!>,
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parameter){ Z4dl'v)9
return getHibernateTemplate().find pwVaSnre`
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(query, parameter); @2~;)*
} I&f!>y?,Z
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public PaginationSupport findPageByCriteria PU-L,]K
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(final DetachedCriteria detachedCriteria){ a(AYY<g
return findPageByCriteria /<k]mY cu
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); +ZR>ul-c
} ojx2[a\
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public PaginationSupport findPageByCriteria ;+*/YTkC+P
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(final DetachedCriteria detachedCriteria, finalint GsoD^mjY
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startIndex){ [$@EQ]tt/
return findPageByCriteria _Mi*Fvj
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(detachedCriteria, PaginationSupport.PAGESIZE, lv#L+}T
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startIndex); 3b/J
} SNC)cq+{
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public PaginationSupport findPageByCriteria 8(]q/g"O
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(final DetachedCriteria detachedCriteria, finalint QsBC[7<jd-
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pageSize, k54b@U52 h
finalint startIndex){ pp+z5
return(PaginationSupport) _adW>-wQ!d
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getHibernateTemplate().execute(new HibernateCallback(){ $ncP#6
publicObject doInHibernate XrJLlH>R4
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(Session session)throws HibernateException { a28`)17z
Criteria criteria = [&)*jc16
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detachedCriteria.getExecutableCriteria(session); BD [<>Wm
int totalCount = s8;*Wt
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((Integer) criteria.setProjection(Projections.rowCount 1]"S?
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()).uniqueResult()).intValue(); eC@b-q
criteria.setProjection xmejoOF
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(null); .ZupsS9l
List items = Hq|{Nt%Q
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criteria.setFirstResult(startIndex).setMaxResults 'VV"$`Fu"
<CWOx&hr
(pageSize).list(); tlgg~MViS
PaginationSupport ps = ^*F'[!. p
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new PaginationSupport(items, totalCount, pageSize, {[bB$~7Eu
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startIndex); p3qKtMs0!
return ps; g6@^n$Y
} *t`=1Ioj
}, true); k/i&e~! \
} xu@+b~C\
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public List findAllByCriteria(final Ah;`0Hz;
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DetachedCriteria detachedCriteria){ hLaQ[9
return(List) getHibernateTemplate \q"vC1,9
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().execute(new HibernateCallback(){ m,Mg
publicObject doInHibernate 2^)_XVX1
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(Session session)throws HibernateException { rnC<(f22
Criteria criteria = [f?x,W~
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detachedCriteria.getExecutableCriteria(session); mcWN.
return criteria.list(); b@B\2BT
} |AS9^w
}, true); /5~j"|
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} G1:"Gxja
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public int getCountByCriteria(final ^2nH6,LPS
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DetachedCriteria detachedCriteria){ q*}$1 zb
Integer count = (Integer) B-wF1!Jv
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getHibernateTemplate().execute(new HibernateCallback(){ 4
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publicObject doInHibernate h5lngw
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(Session session)throws HibernateException { tdNAR|
Criteria criteria = {m"I-VF
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detachedCriteria.getExecutableCriteria(session); 1~S''[
return 9
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criteria.setProjection(Projections.rowCount 0QBK(_O`
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()).uniqueResult(); "sed{?
} X\5EF7:S
}, true); !(sL
return count.intValue(); =-!B4G$
} !*}E
} >[g.8'hI
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用户在web层构造查询条件detachedCriteria,和可选的 RggO|s+0;
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 wvH*<,8Vq
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PaginationSupport的实例ps。 nM`pnR_
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ps.getItems()得到已分页好的结果集 =g)SZK
ps.getIndexes()得到分页索引的数组 jsq|K=x,
ps.getTotalCount()得到总结果数 lN7YU-ygz
ps.getStartIndex()当前分页索引 B~%SB/eu
ps.getNextIndex()下一页索引 9w-;d=(Q
ps.getPreviousIndex()上一页索引 MX7$f (Hy
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 AZnFOS
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,尤其是上面的示例代码,让我着实觉得该对我原来的分页查询做 L7N>p4h]Xj
G$jw#a[L
一下代码重构了。 oSH]TL2@Cd
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我把原本我的做法也提供出来供大家讨论吧: o3.b='HAm
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首先,为了实现分页查询,我封装了一个Page类: Obc wmL
java代码: {mA#'75a#
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/*Created on 2005-4-14*/ jNAboSf2Y
package org.flyware.util.page; r:,"k:C
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/** .FvIT]k-
* @author Joa IDp2#qg_
* hlHle\[ds
*/ o6 8;-b'n
publicclass Page { nu6v@<<F>
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/** imply if the page has previous page */ xS_tB)C
privateboolean hasPrePage; ;eP.B/N
nDXy$f8
/** imply if the page has next page */ Su k;##I
privateboolean hasNextPage; |q 0iX2W
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/** the number of every page */ .WlZT-
privateint everyPage; |qb-iXW=
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/** the total page number */
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privateint totalPage; '^BTa6W}m
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/** the number of current page */ _+qtH< F/
privateint currentPage; V/J-zH&
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/** the begin index of the records by the current
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query */ |L6 +e*
privateint beginIndex; VpB+|%@p
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/** The default constructor */ \5F
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public Page(){ U.J/ "}5`T
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} cN|
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/** construct the page by everyPage :BUr8%l
* @param everyPage ExSy/^4f
* */ Ki%RSW(_`
public Page(int everyPage){ OZno 3Hn
this.everyPage = everyPage; xOc&n0}%
} DC=XPn/V
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/** The whole constructor */ C 4\Q8uK
public Page(boolean hasPrePage, boolean hasNextPage, <2fvEW/#v
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int everyPage, int totalPage, D__*?frWpW
int currentPage, int beginIndex){ K[9{]$(Z
this.hasPrePage = hasPrePage; 86~q pN
this.hasNextPage = hasNextPage; _8OSDW*D5t
this.everyPage = everyPage; 7niI65
this.totalPage = totalPage;
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this.currentPage = currentPage; Wp//SV
this.beginIndex = beginIndex; \PK}4<x}
} u=sZFr@m[
6"La`}B(T8
/** 4z,n:>oH
* @return +qmV|$rmM
* Returns the beginIndex. ^-K~y
*/ t/a
publicint getBeginIndex(){ t<znz6
return beginIndex; }E\u2]
} TuzH'F
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/** oY7 eVu z
* @param beginIndex +'9eo%3O
* The beginIndex to set. 6g'+1%O
*/ ]}BT'fky#
publicvoid setBeginIndex(int beginIndex){ t+n+_X
this.beginIndex = beginIndex; x$24Nc1a'
} vkW]?::Cfd
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/** 79>_aD9
* @return CM+/.y T
* Returns the currentPage. W.
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*/ L_}F.nbS5
publicint getCurrentPage(){ 7)y
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return currentPage; 2-gI@8NPI
} r<-@.$lf
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/** Y> PC>
* @param currentPage [HQ Bx`3TS
* The currentPage to set. Z_[jah
*/ TXK82qTdf
publicvoid setCurrentPage(int currentPage){ R5MY\^H/A
this.currentPage = currentPage; {&.?u1C.\
} A{ a`%FAV
w-?Cg8bq<
/** x-@6U
* @return ZVz`-hB
* Returns the everyPage. f}+8m .g2
*/ D2Dk7//82Y
publicint getEveryPage(){ G:{\-R'
return everyPage; K_LwYO3
} =s1Pf__<k
#[NNb?`F
/** JiCy77H
* @param everyPage `i3fC&?C
* The everyPage to set. d]QCk&XU
*/ w"BMJ+
publicvoid setEveryPage(int everyPage){ 3(>NS ?lX
this.everyPage = everyPage; 'A9U[|
} y7Y g$)sL
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/**
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* @return Zcxj.F(,
* Returns the hasNextPage. KZ/2#`
*/ 1IV
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publicboolean getHasNextPage(){ }
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return hasNextPage; XGMO~8 3
} 'Mm=<Bh
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h
/** #"aL M6Cfs
* @param hasNextPage }A'Ro/n
* The hasNextPage to set.
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*/ V2_I=]p_
publicvoid setHasNextPage(boolean hasNextPage){ VNWa3`w
this.hasNextPage = hasNextPage; b0R{cj=<[
} -XARew
+
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/** /a:L"7z
* @return (Y$48@x
* Returns the hasPrePage. Shb"Jc_i
*/ RT+_e
publicboolean getHasPrePage(){ 5mB'\xGO2
return hasPrePage; z7um9g
} TeWpdUCO
+a((,wAN2
/** 9aZ^m$tAt
* @param hasPrePage lF.yQ
* The hasPrePage to set. sn.&|)?Fi
*/ 'K|tgsvgme
publicvoid setHasPrePage(boolean hasPrePage){ iZDZ/hohv
this.hasPrePage = hasPrePage; N3rQ]HZiP
} My JG2C#R
6pY<,7t0
/** Y'v;!11#
* @return Returns the totalPage. 088"7 s
* u3@v
*/
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publicint getTotalPage(){ qI#ow_lL#
return totalPage; m kHcGB!~
} 3Mt Alc0xp
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/** =
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* @param totalPage MJ0UZxnl
* The totalPage to set. 7__?1n~{
*/ >@c~ M
publicvoid setTotalPage(int totalPage){ _4#&!b6
this.totalPage = totalPage; y<A%&
} ;(,1pi7|
ZP^7`q)6
} ;IX*4E'4s
Z* L{;
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UAq%Y8KA
}g|)+V\A
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 S2*ER
auT'ATW7i
个PageUtil,负责对Page对象进行构造: |=W=H6h*
java代码: hCKx%&[^7
JOm6Zc
J=C63YB
/*Created on 2005-4-14*/ 8'6$t@oT9w
package org.flyware.util.page; Jh)K0>R
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import org.apache.commons.logging.Log; S|?Ht61k
import org.apache.commons.logging.LogFactory; #cD20t
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/** iu(+
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* @author Joa #J<IHNRt
* jwd{CN%
*/ &\/b(|>
publicclass PageUtil { 8x9$6HO
{IpIQ-@l
privatestaticfinal Log logger = LogFactory.getLog e=%6\&q
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(PageUtil.class); ]~A<Q{
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/** 2?bE2^6
* Use the origin page to create a new page +|=5zWI/
* @param page 7yK1Q_XY>
* @param totalRecords 8${Yu
* @return eX@7f!uz
*/ J\ V.J/
publicstatic Page createPage(Page page, int GxR, 3
{BlKVsQ
totalRecords){ Ud8*yB
return createPage(page.getEveryPage(), ';hTGLq\X
oz- k_9%
page.getCurrentPage(), totalRecords); 9?_ybO~Oq
} OnKPD=<
bn$}U.m$-
/** j |tu|Q
* the basic page utils not including exception ^,M&PP6
&G"r>,HU
handler &RP}w%I1
* @param everyPage j$8i!C
* @param currentPage q
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* @param totalRecords {UR&Y
* @return page j2/3NF5&
*/ VF<C#I
publicstatic Page createPage(int everyPage, int 6(X5n5C
>.-$?2
currentPage, int totalRecords){ X;?Z_3I:5
everyPage = getEveryPage(everyPage); 7JNy;$]/
currentPage = getCurrentPage(currentPage); 2m?!!Weq
int beginIndex = getBeginIndex(everyPage, 2iM8V
n_Ka+Y<
currentPage); AIXvS*Y,
int totalPage = getTotalPage(everyPage, Dxwv\+7]
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totalRecords); ,t]qe
boolean hasNextPage = hasNextPage(currentPage, <15POB
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totalPage); -Jtx9P
boolean hasPrePage = hasPrePage(currentPage); 6^DsI
;I+"MY7D
returnnew Page(hasPrePage, hasNextPage, b:iZ.I
everyPage, totalPage, MK<VjpP0(
currentPage, 9A4h?/
s;0eD5b>x
beginIndex); g#ZuRL
} !^|%Z
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privatestaticint getEveryPage(int everyPage){ vsM] <t
return everyPage == 0 ? 10 : everyPage; !j3V'XU#Zn
} IHg)xZ
L#`9# Q
privatestaticint getCurrentPage(int currentPage){ v0dFP0.;&
return currentPage == 0 ? 1 : currentPage; f~.w2Cna
} /~LXY<-(
ecH-JPm'
privatestaticint getBeginIndex(int everyPage, int ClH aR
H<SL=mb;
currentPage){ elgCPX&:W
return(currentPage - 1) * everyPage; Y,bw:vX
} 9o7d3 ir)
#f'(8JjY
privatestaticint getTotalPage(int everyPage, int Y"uFlHN&i
$J |oVVct
totalRecords){ Dk'EKT-
int totalPage = 0; xmDX1sL**
@J~y_J{
if(totalRecords % everyPage == 0) =oF6|\]{;
totalPage = totalRecords / everyPage; ZHshg`I`
else Te8BFcJG
totalPage = totalRecords / everyPage + 1 ; axY-Vj
?[W(r$IaE
return totalPage; RTSR-<{z
} {}3kla{
/)i)wxi
privatestaticboolean hasPrePage(int currentPage){ T$]2U>=<J
return currentPage == 1 ? false : true; T2wn!N?r
} afEp4(X~
W7as=+;X
privatestaticboolean hasNextPage(int currentPage, 6Upg\(
vII8>x%*
int totalPage){ R0<ka[+
return currentPage == totalPage || totalPage == >5Zpx8W
4:}`X
0 ? false : true; 7F-b/AdVq
} 0<L@f=i
lO9{S=N
g[;iVX^1&
} \2<2&=h?
ISr~JQr
r1FE$R~C=
F.=uJdl.!
'KGY;8<x]
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 e![Q1!r
lq@Vb{Z
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 AEwb'
4(4JQ(5
做法如下: 8m A6l0
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 F$ .j|C1a
$UjSP
的信息,和一个结果集List: 2LYd
# !i
java代码: ZZC=
7FB
dW7dMx
1A-8,)
/*Created on 2005-6-13*/ Hcd> \0
package com.adt.bo; i&,U);T
~,e!t.339
import java.util.List; t%z7#}9$
IQ{Xj3;?y
import org.flyware.util.page.Page; 3i(k6)H$4
MatC2-aV1
/** bT-G<h*M
* @author Joa (?\ZN+V)
*/ gE=~.P[ZX
publicclass Result { fnnwe2aso
vP}K(' (
private Page page; oQ;f`JC^
+$>ut
r
private List content; ):78GVp
5 J|;RtcR
/** gSj-~kP
* The default constructor CHpDzG>]4
*/ sW2LNE
public Result(){ `^J~^Z7Y-
super(); %Y Rg1UKY
} *Kzs(O
@@|E1'c7
/** M]` Q4\
* The constructor using fields GP1>h.J
* a`pY&xq::
* @param page eZHzo
* @param content <Awx:lw.
*/ n'*L jp
public Result(Page page, List content){ ~vl: Tb
this.page = page; QrA8KSLC
this.content = content; e3>Re![_.
} -N\{QX1Yd
K[sM)_I
/** ?XOeMI
* @return Returns the content. T%a]3
*/ j|G-9E
publicList getContent(){ <M'IRf/D
return content; 9_>4~!x`
} .`'SL''c
Bhq(bV
/** @I"Aet'XV
* @return Returns the page. ,O~2
R
*/ C-Fp)Zs{0
public Page getPage(){ '*,4F'
return page; j[U0,]
} c?R.SBr,'
[S4\fy0
/** *VlYl"
* @param content hYd8}BvA
* The content to set. |16
:Zoq
*/ VvF&E>fC
public void setContent(List content){ :ZP3$ Dp
this.content = content; J/<`#XZB
} fA,+qs
5N/]/
/** j=AJs<
* @param page =-VV`
* The page to set. >Ed^dsb&
*/ |%V.Lae
publicvoid setPage(Page page){ fBLd5
this.page = page; qBNiuV;*
} `X^e}EGWu
} _@OYC<
kN$70N7I;
H0(zE*c~
Fp]8f&l8
AX,Db%`l,
2. 编写业务逻辑接口,并实现它(UserManager, tJu<#hX
sMS`-,37u
UserManagerImpl) "G,*Z0V5
java代码: Np-D:G
^r& {V"l]
?0(B;[xEJ
/*Created on 2005-7-15*/ O^x t
package com.adt.service; nDOIE)#
oPbD9
import net.sf.hibernate.HibernateException; rODKM-7+
\fKE~61
import org.flyware.util.page.Page; `P5"5N\h
ZkIQ-;wx
import com.adt.bo.Result; LuqaGy}>-
IB6]Wj
/** ;?o C=c
* @author Joa sR9F:
*/ Ii,:+o%
publicinterface UserManager { p_AV3
$KKaA{0-
public Result listUser(Page page)throws W^N"y&
UJH{vjIv
HibernateException; *@&
"MZ/M
1wgu%$|d
} `l+SJLyJ%
LX fiSM{o
Ww(_EW
<di_2hN
~?&ijhZ
java代码: G'py)C5;
flB,_
\+uqP:Ty
/*Created on 2005-7-15*/ X2uX+}h*tA
package com.adt.service.impl;
[dJ\|=
4r. W:}4:
import java.util.List; 19.cf3Dh
vRq xZN
import net.sf.hibernate.HibernateException; DsX>xzM
ZH(.|NaH
import org.flyware.util.page.Page; dvD<>{U,8
import org.flyware.util.page.PageUtil; LbR-uc?x
WNb$2q=
import com.adt.bo.Result; RrHnDO'
import com.adt.dao.UserDAO; +o
import com.adt.exception.ObjectNotFoundException; vOK;l0%
import com.adt.service.UserManager; Xu_<4
S2R[vB4).
/** ! -c*lb
* @author Joa _6m3$k_[MJ
*/ K*Jtyy}r
publicclass UserManagerImpl implements UserManager { K|G$s
ja;5:=8A5
private UserDAO userDAO; Vi#im`@
>>$|,Q-.
/** [tzSr=,Cg
* @param userDAO The userDAO to set. {K9E% ,w
*/ c Vn+~m_%
publicvoid setUserDAO(UserDAO userDAO){ V)2_T!e%*
this.userDAO = userDAO; +*J4q5;E[?
} c2^7"`
OkZ! ZS
h
/* (non-Javadoc) pD# "8h
* @see com.adt.service.UserManager#listUser I{zE73
yU|ji?)e
(org.flyware.util.page.Page) uB1!*S1f
*/ MI(i%$R-A
public Result listUser(Page page)throws 5G!U'.gr
AE&n^vdQW
HibernateException, ObjectNotFoundException { GX)QIe~;qJ
int totalRecords = userDAO.getUserCount(); :*@|"4
if(totalRecords == 0) *$(CiyF!
throw new ObjectNotFoundException @(c<av?
@S7=6RKa[
("userNotExist"); n6G&^Oj
page = PageUtil.createPage(page, totalRecords); =BS'oBn^6
List users = userDAO.getUserByPage(page); XQOprIJ
U
returnnew Result(page, users); SSLshY~d
} udGGDH
zt2-w/[Q
} g&TCff
z,|%?
1
rhTk}2@h
r$FM8$cJ
z[%v_S
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 xD#I&.
G=cH61
询,接下来编写UserDAO的代码: 2w|u)ow)
3. UserDAO 和 UserDAOImpl: 9'q /&uH
java代码: +)JqEwCrq
|u ;BAb
TDIOK
/*Created on 2005-7-15*/
hu(K!>{
package com.adt.dao; `_U0>Bfg;
FRt/{(jro
import java.util.List; Zk#i9[g9*
y] ]Vp~R:[
import org.flyware.util.page.Page; ^Cn]+0G#C8
ff1B)e
import net.sf.hibernate.HibernateException; HoE.//b
R9/xC7l@
/** j' KobyX<
* @author Joa hS{
*l9v7
*/ eBTedSM?t
publicinterface UserDAO extends BaseDAO { y/I~x+y
q;../h]Ne
publicList getUserByName(String name)throws J+ZdZa}Ob
$lAb6e$n
HibernateException; e'Us(]ZO
[y[v]'
publicint getUserCount()throws HibernateException; `$Fl gp0P
ICbdKgLz
publicList getUserByPage(Page page)throws Zmbz-##HQ
qV8\/7'A0a
HibernateException; Ym{%"EB
qm8n7Z/
} C.)&FW2F_
Bb[e[,ah
gDNTIOV
y2"S\%7$h
z!C4>,
java代码: G\>\VA
+.#S[G
uxMy1oy
/*Created on 2005-7-15*/ <Mn7`i
package com.adt.dao.impl; &iiK ZZ`_o
!BQ ELB$0
import java.util.List; K:
o|kd
O|OSE
import org.flyware.util.page.Page; a^\- }4yR
PtQ#
import net.sf.hibernate.HibernateException; 8pL>wL
&C
import net.sf.hibernate.Query; Ky9No"o
XBWSO@M'
import com.adt.dao.UserDAO; FHNuMdFn
R c:cVK
/** M |Q
* @author Joa JeTrMa 2
*/ EM54
public class UserDAOImpl extends BaseDAOHibernateImpl
wy_;+ 'Y
e|5B1rMM
implements UserDAO { tct5*.|
"o# )vA`
/* (non-Javadoc) ssX6kgq_(
* @see com.adt.dao.UserDAO#getUserByName @)Hbgkdi
zGL<m0C
(java.lang.String) W3{<e"
*/ iWN.3|r
publicList getUserByName(String name)throws $:u7Dv}\
3@TG.)N4
HibernateException { ),p]n
String querySentence = "FROM user in class f-v ND'@
*fvI.cKiGP
com.adt.po.User WHERE user.name=:name"; ?9zoQ[
Query query = getSession().createQuery ~?`9i>3W~
W`/jz/
(querySentence); r6`^>c
query.setParameter("name", name); J'&B:PZObB
return query.list(); !/Bw,y ri<
} Avv
mam5G!$
/* (non-Javadoc) *Nf4bH%MN
* @see com.adt.dao.UserDAO#getUserCount() 4&]To@>
*/ z)W#&JFF
publicint getUserCount()throws HibernateException { ^tg6JB;s
int count = 0; !: EW21m
String querySentence = "SELECT count(*) FROM lQ<#jxp
tU)r[2H2
user in class com.adt.po.User"; 0bPJEEd
Query query = getSession().createQuery k$0|^GL8
i_9Cc$Qh<
(querySentence); ;!0.Kk
4
count = ((Integer)query.iterate().next + 1+A3
*`g-gk
()).intValue(); Z\*5:a]
return count; +6#%P
} %KJhtd"q
@q{:Oc^
/* (non-Javadoc) k{}[>))Q
* @see com.adt.dao.UserDAO#getUserByPage rtYb"-&
~E3SC@KL
(org.flyware.util.page.Page) >Oi2gPA
*/ x<{;1F,k3
publicList getUserByPage(Page page)throws &w;^m/zP3
>G4HZE
HibernateException { 5}X<(q(
String querySentence = "FROM user in class anz9lGG#
VM<oUKh_3
com.adt.po.User"; V
4\^TO`q=
Query query = getSession().createQuery 1%/ NL?8#
hk"9D<&i>b
(querySentence); a_ 9 |xI
query.setFirstResult(page.getBeginIndex()) m|nL!Wc
.setMaxResults(page.getEveryPage()); J/]o WC`u
return query.list();
CSG+bqUG
} G%j/eTTf
\~z?PA.$
} \sHy. {
VNr
*@ <8&M9x
MfNpQ: ]c\
75\RG+kQ
至此,一个完整的分页程序完成。前台的只需要调用 4+/fP
x ^M5D+o
userManager.listUser(page)即可得到一个Page对象和结果集对象 0gv3v@QO
P^K?E
的综合体,而传入的参数page对象则可以由前台传入,如果用 \'s$ZN$k
xJ=ZQ)&]
webwork,甚至可以直接在配置文件中指定。 r}_Lb.1]
;l/}Or2
下面给出一个webwork调用示例: +K$5tT6b
java代码: M9(ez7Z
{.aK{
V
W2F+^
/*Created on 2005-6-17*/ Nh1e1m?
package com.adt.action.user; ?dJ/)3I%F
zt)p`kd D
import java.util.List; L)kb (TH
(<]\,pP0_
import org.apache.commons.logging.Log; #514a(6
import org.apache.commons.logging.LogFactory; pIZLGsu[
import org.flyware.util.page.Page; r6F{
,<0Rf
import com.adt.bo.Result; RI[7M (
import com.adt.service.UserService; PmPyb>HK=P
import com.opensymphony.xwork.Action; b!4N)t>gl
;PfeP;z
/** R
"/xne
* @author Joa 2A*X Hvwb
*/ )Y&MIJ7>@
publicclass ListUser implementsAction{ ]^yV`Z8
GZ/pz+)i&
privatestaticfinal Log logger = LogFactory.getLog ?Kx6Sf<i
95.qAFB1
(ListUser.class); cW81
R/ALR
private UserService userService; z9k*1:
g:3d<CS
private Page page; msA' 5>
ShL1'Z}^{
privateList users; PtVo7zOye
86;+r'3p.
/* G*P[z'K=
* (non-Javadoc) h.4qlx|
* }j+~'O4m
* @see com.opensymphony.xwork.Action#execute() qy7hkq.uX
*/ fbh6Ls/
publicString execute()throwsException{ olD@W
UB
Result result = userService.listUser(page); vh9kwJyT
page = result.getPage(); b{~fVil$y
users = result.getContent(); %+AS0 JhB
return SUCCESS; T7>48eH
} I!|y;mh:it
ntrY =Y
/** 8Zcol$XS'
* @return Returns the page. n~1tm
*/ (l\a '3a.
public Page getPage(){ }G>v]bV0V
return page; Ez06:]Jd
} |_l<JQvf`E
C-s>1\I
/** 9nT?|n]>
* @return Returns the users. Zvd ;KGO(a
*/ x2
w8zT6M
publicList getUsers(){ R'*<A3^
return users; ^-gfib|VGe
} _v1bTg"?
lTa1pp
Zw
/** ljNzYg~-
* @param page *0=fT}&!
* The page to set. Nc
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*/ KotPV
publicvoid setPage(Page page){ T{_1c oL
this.page = page; @PYW|*VS
} E)KB@f<g*
f:_=5e
+
/** Oq #o1>
* @param users DY)D(f/&3
* The users to set. n?y'c^
*/ Dl0/-=L
publicvoid setUsers(List users){ F{TC#J}I%'
this.users = users; y<O@rD8iA
} 8B}'\e4i
*<B)Z
/** yr
FZ~r@-
* @param userService *D\0.K,o
* The userService to set. pG)9=X!9
*/ P#AAOSlLV
publicvoid setUserService(UserService userService){ gsW=3m&`
this.userService = userService; Z6 t E{/
} ?RZq =5Um&
} k%{ l4
t{+M|Y
o)0C-yO0qf
77+|#<J
6{5q@9F
上面的代码似乎看不出什么地方设置了page的相关初值,事实上, D~cW
]2
=YWT|%^uX
可以通过配置文件来进行配置,例如,我想每页显示10条记录,那 mG0L !5
aML#Z |n
么只需要: dVvZu% DFp
java代码: 9OPK4-
v2IEJ
*y)4D[
z-
<?xml version="1.0"?> #0}Ok98P
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork )J;ny!^2
6a7vlo
1.0//EN" "http://www.opensymphony.com/xwork/xwork- +c-6#7hh
uZ@-e|qto
1.0.dtd"> ksTzXG8
{d| |q<.-
<xwork> 7raSf&{&6b
LEWa6'0rq
<package name="user" extends="webwork- r])Z9bbi
IbF4k.J
interceptors"> KA`0g=
[6O04"6K
<!-- The default interceptor stack name @XeEpDn]
9~=gwP
--> 1Wv{xML"
<default-interceptor-ref #]@9qPyn
U?^OD
name="myDefaultWebStack"/> lco~X DI
^SEc./$
<action name="listUser" IDj_l+?c
p`\3if'
class="com.adt.action.user.ListUser"> cvhlRI%6
<param _8al
A_@I_V$
name="page.everyPage">10</param> FH4u$g+
<result a|U}Ammr
I=U+GY:
name="success">/user/user_list.jsp</result> ]y.Rg{iv
</action> VF\{ra;
l`DtiJ?$$0
</package> Y=9qJ`q
]Qd{ '}+
</xwork> dl:-k r8
it~Z|$
~
W@X-
:]yg
`Uv)Sf{
tzPC/?
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 )Ea8{m!
Hc M~
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。
[ne"
T
+)zDA:2Wa"
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 I|Z/`9T
|P>|D+I0
k'g$2
c&
3#-DNI
u %'y_C3
我写的一个用于分页的类,用了泛型了,hoho QGXQ {
o_sQQF
java代码: y86))
0D<TF>M;pn
cI3 y
package com.intokr.util; p'gb)nI
?d4Boe0-a2
import java.util.List; NIaF 5z
YwGHG{?e
/** ^xt9pa$f
* 用于分页的类<br> TMqY4;UeL
* 可以用于传递查询的结果也可以用于传送查询的参数<br> 7(NXCAO81
* A?DB#-z.r
* @version 0.01 t=Jm|wJnUA
* @author cheng 3|zgDA
*/ ,7<DGI_y
public class Paginator<E> { nx B32
privateint count = 0; // 总记录数 Q{[@`bZB
privateint p = 1; // 页编号 Lbsr_*4t
privateint num = 20; // 每页的记录数 9^au$KoU
privateList<E> results = null; // 结果 +>4^mE" \
iTu0T!4F
/** )%qtE34`
* 结果总数 ~\[?wN
*/ l0Y?v 4
publicint getCount(){ VRtO; F
return count; IO"hF
} )yrAov\z*
./7v",#*.'
publicvoid setCount(int count){ Sl"BK0:%7
this.count = count; K^aj@2K{
} nS.2C>A
qi&D+~Gv!
/** Ib6(Bp9.L
* 本结果所在的页码,从1开始 d/]|657u
* k1#5nYN.
* @return Returns the pageNo. -6`;},Yr
*/ a8zZgIV
publicint getP(){ nkRK+~>
return p; E?cZbn*>`
} lVoik*,B
(UGol[f<
/** 'B`#:tX^N
* if(p<=0) p=1 c" +zgP
* #]y5zi
* @param p O#:&*Mv
*/ =JW[pRI5a
publicvoid setP(int p){ ' S ,2
if(p <= 0) &{ ZSE^
p = 1; 4jGLAor|
this.p = p; U(*yL-
} {fU?idY)c
qp&4 1
/** `|EH[W&y
* 每页记录数量 nvt$F%+
*/ k;Hnu
publicint getNum(){ I+",b4
return num; AkA!:!l
} @1bH}QS
OJpj}R
/** 'E -FO_N
* if(num<1) num=1 ^C7C$TZS
*/ G6Nb{m
publicvoid setNum(int num){ \ha-"Aqze3
if(num < 1) )7Ixz1I9g
num = 1; W5Zqgsy($F
this.num = num; #9:2s$O[x
} mxp Y&Y
yFjVKp'P
/** PS@ *qTin
* 获得总页数 Ri @`a
*/ J633uH}}
publicint getPageNum(){ 7W|Zq6pi
return(count - 1) / num + 1; :gf;}
} k. GA8=]>
hcyO97@r
/** .S7:;%qL6
* 获得本页的开始编号,为 (p-1)*num+1
"SR5wr
*/ "hPCQp`Tj
publicint getStart(){ <lj\#'G3
return(p - 1) * num + 1; R ]P;sk5
} >1ZJ{se
6 P*O&1hv
/** sS9%3i/>
* @return Returns the results. TzKK;(GX
*/ !ni>\lZ
publicList<E> getResults(){ K5`Rk"s
return results; Js{=i>D
} OipqoI2
6(KmA-!b(O
public void setResults(List<E> results){ URw5U1
this.results = results; K9|7dvzC:
} !h: Q
eW50s`bKY
public String toString(){ <n^3uXzD
StringBuilder buff = new StringBuilder .~mCXz<x
*7RvHHf
(); Z 0*%Rq
buff.append("{"); 3ZojE ux`
buff.append("count:").append(count); <kbyZXV@K
buff.append(",p:").append(p); KOSQQf
o
buff.append(",nump:").append(num); ;`UecLb#
buff.append(",results:").append ~pz FZ7n4
tsv$ r$Se
(results); Lgi[u"Du
buff.append("}"); ]db@RbaH
return buff.toString(); kg>>D
} o@k84+tn(
h{_*oBa
} 0m)&YFZ[(
4l @)K9F
f$F*3