Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 R&PQU/t)
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 Tl6%z9rY@
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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 "hdcB
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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 h/W@R_Y
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分页支持类: "9:1>Gr{G
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java代码: +q[puFfl
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package com.javaeye.common.util; ,Y6Me+5B
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import java.util.List; ZnVi.s~1V
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publicclass PaginationSupport { 5B)Z@-x2
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publicfinalstaticint PAGESIZE = 30; zc%#7"FM
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privateint pageSize = PAGESIZE; :
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privateList items; nSdta'6
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privateint totalCount; SRuNt3wW6
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privateint[] indexes = newint[0]; l$=Y(Xk
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privateint startIndex = 0; Q5b~5a
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public PaginationSupport(List items, int q^ lx03
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totalCount){ wyvrNru<l4
setPageSize(PAGESIZE); M}MXR=X,
setTotalCount(totalCount); O:3LA-vA
setItems(items); %Aq+t&-BCX
setStartIndex(0); ="hh=x.5J
} 8T6.Zhv
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public PaginationSupport(List items, int %9B r
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totalCount, int startIndex){ `&xo;Vnc
setPageSize(PAGESIZE); ! c,=%4Pb
setTotalCount(totalCount); z'OY6
setItems(items); 2YI#J.6]H
setStartIndex(startIndex); r*CI6yP
} {eo4J&as
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public PaginationSupport(List items, int -F\xZ
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totalCount, int pageSize, int startIndex){ 'S]7:/CI
setPageSize(pageSize); mv_N ns
setTotalCount(totalCount); ,*ZdMw!
setItems(items); Q[+&n*
setStartIndex(startIndex); <J" 7ufHSQ
} XG2&_u&
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publicList getItems(){ (:v|(Gn/
return items; Qvo(2(
} O&h3=?O&B
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publicvoid setItems(List items){ t-7^deG'/n
this.items = items; +s?0yH-%p
} _' KJ:3e
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publicint getPageSize(){ Hg$t,\j
return pageSize; ~u|k1
} R+,eX jz"
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publicvoid setPageSize(int pageSize){ v%N/mL+5L
this.pageSize = pageSize; aD)XxXwozm
} lYEMrr!KQw
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publicint getTotalCount(){ 1|/P[!u
return totalCount; W3K&C[f
} qOOF]L9r%u
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publicvoid setTotalCount(int totalCount){ 4pNIsjl}
if(totalCount > 0){ 1UG5Q-
this.totalCount = totalCount; (3PkTQlE
int count = totalCount / -XNjyXm2
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pageSize; =[{YI2S
if(totalCount % pageSize > 0) 78a!@T1#
count++; )\fAy
indexes = newint[count]; Zqwxi1
for(int i = 0; i < count; i++){ '@OqWdaR
indexes = pageSize * "o"ujQ(v
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i; TTB1}j+V6
} 8/ lv, m#
}else{ "]*16t%Z%x
this.totalCount = 0; f`Km ctI
} f44b=,Lry5
} :6R0=oz
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publicint[] getIndexes(){ W[B%,Km%]
return indexes; pe(31%(h
} %g1{nGah
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publicvoid setIndexes(int[] indexes){ Mle@.IIT
this.indexes = indexes; oJ|8~:)
} FnkB
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publicint getStartIndex(){ MR8\'0]
return startIndex; z@@w?>*
} cTpmklq
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publicvoid setStartIndex(int startIndex){ 8$Igo$U-
if(totalCount <= 0) .1F(-mLd
this.startIndex = 0; xRum q
elseif(startIndex >= totalCount) $gKMVgD"
this.startIndex = indexes 0sxZa+G0o
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[indexes.length - 1]; Qn`$xY9mT
elseif(startIndex < 0) iaShxoIV
this.startIndex = 0; gT 8^
else{ ]WZ_~8
this.startIndex = indexes Ml &Cr
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[startIndex / pageSize]; A4!IbJD,0
} nsO!
} ~3p
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publicint getNextIndex(){ L0ZgxG3:g
int nextIndex = getStartIndex() + %C&HR2
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pageSize; Yr9>ATR
if(nextIndex >= totalCount) _"BYnPq@wb
return getStartIndex(); {O\>"2}m'f
else ?,Z[)5 ZN
return nextIndex; t{)Z$)'
} c;\}R#
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publicint getPreviousIndex(){ kz4d"bTb
int previousIndex = getStartIndex() - Be?b|
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pageSize; J
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if(previousIndex < 0) 'k|?M
return0; v9Kx`{1L
else '2`MT-
return previousIndex; B(}u:[
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} R <kh3T
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} v0pyyUqS
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抽象业务类 e;LJdd
java代码: ` oBlv
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/** K \?b6;ea
* Created on 2005-7-12 gO
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*/ 1$cX`D`
package com.javaeye.common.business; [8Zq
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import java.io.Serializable; ppv/A4Kv
import java.util.List; Fi8'3/q-^
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import org.hibernate.Criteria; [Xy^M3
import org.hibernate.HibernateException; 9C-!I,
import org.hibernate.Session; -8-BVU
import org.hibernate.criterion.DetachedCriteria; Vwj^h
import org.hibernate.criterion.Projections; RS`]>K3t
import '%!'1si
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org.springframework.orm.hibernate3.HibernateCallback; L,I5/K6
import -C9_gZ
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org.springframework.orm.hibernate3.support.HibernateDaoS etY/K0
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upport; g.CUo:c
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import com.javaeye.common.util.PaginationSupport; C)2Waj}
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public abstract class AbstractManager extends .gPE Qc+D
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;
HibernateDaoSupport { zbL!q_wO
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privateboolean cacheQueries = false; 6#NptXB
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privateString queryCacheRegion; <OG rC .k}
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publicvoid setCacheQueries(boolean FB<#N+L\
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cacheQueries){ >BC?%|l
this.cacheQueries = cacheQueries; *W()|-[V3
} W_z2Fs"A
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publicvoid setQueryCacheRegion(String E;l|I
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queryCacheRegion){ ~T<yp
this.queryCacheRegion = EC6)g;CO
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queryCacheRegion; ,3^gB,ka
} 0>#or$:6E
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publicvoid save(finalObject entity){ 11Kbj`sRZ
getHibernateTemplate().save(entity); *&VH!K#@{
} u(ep$>[F#_
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publicvoid persist(finalObject entity){ -eKi}e
getHibernateTemplate().save(entity); FI,>v`
} *Vk%"rwaG
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publicvoid update(finalObject entity){ ~GL"s6C$`;
getHibernateTemplate().update(entity); $ t' .
} (<?6X9F:N
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publicvoid delete(finalObject entity){ 5@3[t`n'
getHibernateTemplate().delete(entity); +dWx?$n
} K\5'pp1
: `D[0
publicObject load(finalClass entity, m&)5QX
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finalSerializable id){ _=RA-qZ"
return getHibernateTemplate().load r&AX
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(entity, id); &
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} M{Ss?G4H
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publicObject get(finalClass entity, 2UYtFWB9o
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finalSerializable id){ >sAZT:&gv
return getHibernateTemplate().get %-? :'F!1
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(entity, id); ZKKz?reM'
} G{*m] 0Q
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publicList findAll(finalClass entity){ MS{purD
return getHibernateTemplate().find("from -^=sxi,V
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" + entity.getName()); oY@4G)5
} ]^,<Ez
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publicList findByNamedQuery(finalString (g2?&b
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namedQuery){ $x&@!/&|pv
return getHibernateTemplate *@'4 A :A
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().findByNamedQuery(namedQuery); G%N/]]ll
} %AbA(F
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publicList findByNamedQuery(finalString query, +RexQE
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finalObject parameter){ +W+O7SK\y
return getHibernateTemplate td^2gjr^5
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().findByNamedQuery(query, parameter); !4uTi [e
} (uG.s %I
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publicList findByNamedQuery(finalString query, 3nt&Sf
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finalObject[] parameters){ n`";ctQT
return getHibernateTemplate fsa
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().findByNamedQuery(query, parameters); %FnaS
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} EL+6u>\-k
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publicList find(finalString query){ K
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return getHibernateTemplate().find 1aKYxjYM
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(query); 0'!v-`.
} m#SDB6l
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publicList find(finalString query, finalObject Dt,b\6
& f7 {3BK
parameter){ yoTbIQ
return getHibernateTemplate().find ?29zcuRaru
@xR7>-$0p
(query, parameter); t1p}
} 6zK8-V?9F
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public PaginationSupport findPageByCriteria zAEq)9Y"l'
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(final DetachedCriteria detachedCriteria){ 9"_JiX~3
return findPageByCriteria Ws?BAfP
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); ? lC.
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} A#~"Gp
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public PaginationSupport findPageByCriteria _+0l+a*D
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(final DetachedCriteria detachedCriteria, finalint l c)*HYqU
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startIndex){ X1U7$/t
return findPageByCriteria =jdO2MgSg*
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(detachedCriteria, PaginationSupport.PAGESIZE, xB{0lI
}OO(uC2
startIndex); vlCjh! x
} fLK*rK^{"
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public PaginationSupport findPageByCriteria vTN/ho,H
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(final DetachedCriteria detachedCriteria, finalint 7"F
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pageSize, rP.qCl+J
finalint startIndex){ ($*bwqp]}
return(PaginationSupport) ]Po9a4w#
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getHibernateTemplate().execute(new HibernateCallback(){ FRI<A8
publicObject doInHibernate $Ch!]lJA
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(Session session)throws HibernateException { h.c<A{[I6c
Criteria criteria = :)}iWKAse
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detachedCriteria.getExecutableCriteria(session); )
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int totalCount = ~rEU83
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((Integer) criteria.setProjection(Projections.rowCount log{jF
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()).uniqueResult()).intValue();
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criteria.setProjection "m +Eu|{
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(null); pc&/'zb
List items = vC~];!^
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criteria.setFirstResult(startIndex).setMaxResults `+$'bNPn&
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(pageSize).list(); -xq)brG
PaginationSupport ps = =zXpeo&|m
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new PaginationSupport(items, totalCount, pageSize, ~Kda#=
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startIndex); uRG0}>]|U
return ps; [P)'LY6F
} >FPE%X0+
}, true); |Q:$G!/
} qgrRH'
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public List findAllByCriteria(final `Bx3grZ
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DetachedCriteria detachedCriteria){ i;xH
return(List) getHibernateTemplate BZEY^G
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().execute(new HibernateCallback(){ QlIg'B6
publicObject doInHibernate p3 I{
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(Session session)throws HibernateException { =IV_yor
Criteria criteria = ,GXwi|Y
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detachedCriteria.getExecutableCriteria(session); qa#Fa)g*
return criteria.list(); @B5@3zYs
} [P8Y
}, true); +Y(cs&V*
} c#nFm&}dm
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public int getCountByCriteria(final 'p-jMD}O
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DetachedCriteria detachedCriteria){ I<|)uK7
Integer count = (Integer) (:2:_FL
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getHibernateTemplate().execute(new HibernateCallback(){ mbv\Gn#>
publicObject doInHibernate ,@%1q)S?A
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(Session session)throws HibernateException {
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Criteria criteria = sR,]eo<p&
* X\i=
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detachedCriteria.getExecutableCriteria(session); 1i#uKKwE
return r&)/3^S '
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criteria.setProjection(Projections.rowCount xksQMS2#
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()).uniqueResult(); EHkb{Q8
} k:s}`h_n
}, true); k(<5tv d
return count.intValue(); HxAq& J;xu
} \k0%7i[nZ/
} PXm{GLXRS;
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用户在web层构造查询条件detachedCriteria,和可选的 <<@\K,=
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 -"u}lCz>
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PaginationSupport的实例ps。 N72z5[..
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ps.getItems()得到已分页好的结果集 pBiC
ps.getIndexes()得到分页索引的数组 [J\5DctX;c
ps.getTotalCount()得到总结果数 9_JK.
ps.getStartIndex()当前分页索引 'VFxg,
ps.getNextIndex()下一页索引 9=@j]g|
ps.getPreviousIndex()上一页索引 o,9E~Q '`{
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 3!Zd]1$
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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 I!9u](\0
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一下代码重构了。 cf1Ve\(YGI
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我把原本我的做法也提供出来供大家讨论吧: -en:81a#
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首先,为了实现分页查询,我封装了一个Page类: OJ8W'"`L&
java代码: v3[Z]+ ]
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/*Created on 2005-4-14*/ Y oNg3
package org.flyware.util.page; T
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/** OgyETSN8C
* @author Joa d?WA}VFU
* dMw7Lp&
*/ `B) ~
publicclass Page { XD{U5.z>y
sn_]7d+Q
/** imply if the page has previous page */ 5X\3y4
privateboolean hasPrePage; ,Bp\ i
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/** imply if the page has next page */ Z}f$KWj
privateboolean hasNextPage; X/lLM`
i96Pel
/** the number of every page */ xU@YBzbk
privateint everyPage; 7A8jnq7m/
eHF#ME
/** the total page number */ gsI"G
privateint totalPage; eJilSFp1
5g&.P\c{
/** the number of current page */ PP/M-Jql)
privateint currentPage; AnU,2[(
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/** the begin index of the records by the current CY)/1 # J
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query */ _zI95
privateint beginIndex; QOlm#S
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/** The default constructor */ ;TF(opW:
public Page(){ Vk y~yTL)\
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} 3qiE#+dC
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/** construct the page by everyPage _xI'p6C
* @param everyPage qw&Wfk\}
* */ />Tyiy]2uu
public Page(int everyPage){ i]Lt8DiRq
this.everyPage = everyPage; `/f9
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} C 6Bh[:V&
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/** The whole constructor */ :1q+[T/ @
public Page(boolean hasPrePage, boolean hasNextPage, UAnq|NJO
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%h g=@7,|
int everyPage, int totalPage, ~1`.iA
int currentPage, int beginIndex){ SOE#@{IXBa
this.hasPrePage = hasPrePage; <_uLf9ja
this.hasNextPage = hasNextPage; )W:`Q&/G
this.everyPage = everyPage; lu`\6
this.totalPage = totalPage; mG7Wu{~=U
this.currentPage = currentPage; 1}tZ,w>
this.beginIndex = beginIndex; yAU[A
} |rH;}t|un
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/** %Xh/16X${
* @return chQt8Ar3
* Returns the beginIndex. S6h=}
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*/ e-,U@_B
publicint getBeginIndex(){ .S`Ue,H
return beginIndex; "Fy34T0N
} >J[g)$,
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/** Pg-~^"?y
* @param beginIndex 1HskY| X
* The beginIndex to set. Oq(_I
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*/ /4YXx|V
publicvoid setBeginIndex(int beginIndex){ 24:;vcb
this.beginIndex = beginIndex; [g]ks
} eQx9Vnb
v/c8P\
/** iH#~eg
* @return VFT
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* Returns the currentPage. 8js5/G+
*/ 2"~!Pu^.j
publicint getCurrentPage(){ <P3r+ 1|R
return currentPage; HLg/=VF7?
} 1Z'cL~9
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/** FviLlly6
* @param currentPage -TU7GCb=
* The currentPage to set. Nb>|9nu
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*/ %:h)8e-;
publicvoid setCurrentPage(int currentPage){ w
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this.currentPage = currentPage; W=j/2c/
} @X>k@M
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/** Kf76./
* @return LZMdW
#,[
* Returns the everyPage. $)mq
*/ %.r{+m
publicint getEveryPage(){ r) T^ Td1
return everyPage; <GF)5QB
} <^UB@'lCm
9U>ID{
/** TYw0#ZXo
* @param everyPage g^NdN46%
* The everyPage to set. 5~<>h~yJ
*/ )-Zpr1kD
publicvoid setEveryPage(int everyPage){ 6TbDno/!'
this.everyPage = everyPage; N;>>HN[bBP
} fGcAkEstT!
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/** tE]g*]o
* @return ,ZJI]Q=!
* Returns the hasNextPage. Z@nM\/vLA
*/ )F0_V
4
publicboolean getHasNextPage(){ 'X_iiR8n@p
return hasNextPage; @z EEX9U
} Y$--Hp4
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/** JS642T
* @param hasNextPage e!l!T@
pf
* The hasNextPage to set. aa_&WHXkt
*/ hQ i[7r($8
publicvoid setHasNextPage(boolean hasNextPage){ y%|nE((
this.hasNextPage = hasNextPage; t^&:45~Q
} Oo`P +S#
n]}+ :
/** UIv TC
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* @return n4 KiC!*i0
* Returns the hasPrePage. ^LfCLI9Z
*/ ~2
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publicboolean getHasPrePage(){ G-G!c2o
return hasPrePage; Z_iu^Q
} #-'=)l}i1A
=jkC]0qx
/** aj20, w
* @param hasPrePage MnO,Cd6{%d
* The hasPrePage to set. ^8o'\V"m^
*/ /1h`O@VA
publicvoid setHasPrePage(boolean hasPrePage){ m`g%\o^6i
this.hasPrePage = hasPrePage; #KXaz Zu"
} Y6`9:97
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/** .i"v([eQ
* @return Returns the totalPage. % rdW:
* ^OI
*/ -fj;9('YJ
publicint getTotalPage(){ CJJ 1aM
return totalPage; @~ N:F~
} 4(R O1VWsb
a)(j68c
/** //JF$o=)D
* @param totalPage %aaOws
* The totalPage to set. @I]uK[qd
*/ la8se=^
publicvoid setTotalPage(int totalPage){ Vvm6T@b M8
this.totalPage = totalPage; b*nytF
} ;J2U5Y NO
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} $9y]>R
}kT;UdIu;
%{yr#F=t#]
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上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 9|v
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个PageUtil,负责对Page对象进行构造: 8doT`rI1
java代码: :GIY"l'
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/*Created on 2005-4-14*/ 6](vnS;
package org.flyware.util.page; l'W?X '
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import org.apache.commons.logging.Log; go]d+lhFB
import org.apache.commons.logging.LogFactory; |^S[Gr w
8.o[K
/** 9*[!uu
* @author Joa st{:]yTRk
* DA]!ndJD
*/ K^J;iu 4
publicclass PageUtil { RT9fp(6*
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privatestaticfinal Log logger = LogFactory.getLog %;yo\
1|;WaO1Q
(PageUtil.class); jn^i4f>N
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/** 6aM`qz)
* Use the origin page to create a new page lDe9EJR
* @param page #Q^mdv?
* @param totalRecords Cs^o- g!L
* @return HNY{%D
*/ r;y&Wa
publicstatic Page createPage(Page page, int jS5e"LMIq
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totalRecords){ N?kXATB
return createPage(page.getEveryPage(), c[sC 2
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page.getCurrentPage(), totalRecords); ZB`!@/3X
} Kw(/#C:$
S? r:=GS
/** ]}ff*W
* the basic page utils not including exception l2gI2Cioa
L^RyJ;^c
handler `*KS`
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* @param everyPage iFF/[P
* @param currentPage ~SV;"e2N.
* @param totalRecords
*X*D,
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* @return page QDBptI:
*/ klT6?'S
publicstatic Page createPage(int everyPage, int PgB=<#9
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currentPage, int totalRecords){ 2EG"xA5%
everyPage = getEveryPage(everyPage); bkmX@+Pe
currentPage = getCurrentPage(currentPage); @`%.\_
int beginIndex = getBeginIndex(everyPage, #@2 `^1
}=?r`J+Ev;
currentPage); AW+4Vm_!l
int totalPage = getTotalPage(everyPage, ClaYy58v
p&Nw:S
totalRecords); Kl(}s{YFn.
boolean hasNextPage = hasNextPage(currentPage, 8Ral%I:gr
;f?OT7>kN
totalPage); d^ipf*aLC
boolean hasPrePage = hasPrePage(currentPage); A
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OTN"XKa$
returnnew Page(hasPrePage, hasNextPage, U=Z@Ipu5T
everyPage, totalPage, %04>R'mN
currentPage, Y
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-<ZzYQk^h
beginIndex); tDy1Gh/c
} fN0D\Mu!)b
aR}NAL_`w
privatestaticint getEveryPage(int everyPage){ m"86O:S#d
return everyPage == 0 ? 10 : everyPage; +(PtOo.
} at7/KuY!~
BAX])~_
privatestaticint getCurrentPage(int currentPage){ bTO$B2eh|
return currentPage == 0 ? 1 : currentPage; d`({z]W;
} *'d5~dz=
<u4GIi
<sm
privatestaticint getBeginIndex(int everyPage, int &bBp`h
h=`rZC
currentPage){ lba*&j]w=
return(currentPage - 1) * everyPage; G`6U t
} 3AWB Y.
<Y~V!9(~{Q
privatestaticint getTotalPage(int everyPage, int YV!!bI
y"t5%Iv
totalRecords){ #n2GW^x
int totalPage = 0; G|3OB:
rQKBT]?y
if(totalRecords % everyPage == 0) Bw{@YDO{
totalPage = totalRecords / everyPage; iW*0V3
else FuEHO 6nx
totalPage = totalRecords / everyPage + 1 ; cTRCQ+W6:
pC5-,Z;8
return totalPage; `q$DNOrS
} eHqf3f
yQou8P=%
privatestaticboolean hasPrePage(int currentPage){ JN|<R%hy
return currentPage == 1 ? false : true; B-@f.NO/s
} Ta9;;B?$
[POy"O
privatestaticboolean hasNextPage(int currentPage, >4h4t/G
$?*+P``
int totalPage){ jLb3{}0
return currentPage == totalPage || totalPage == >z[d~
tvFJ^5
0 ? false : true; T,WWQm
} ?W.Y
x7c
xl# j_d,
KVQZ
} I,
!Y\hF|[z
HnOF_Twq
w`!Yr:dU
ORfA]I-u
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。 Kl+*Sp!
HF47Lc*c
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
0;k3
ZQ~?
做法如下: $1Xg[>1g5
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 b[*di{?-
veK
的信息,和一个结果集List: vP,WV9Q1u
java代码: *}mtVa_|
_10#rucr
J4S2vBe16
/*Created on 2005-6-13*/ 78 UT]<Q;K
package com.adt.bo; J~c]9t
<D&75C#
import java.util.List; g2iSc
(AwbZ n*
import org.flyware.util.page.Page; *&5G+d2
!w
C4ei`
/** 8Oc*<^{#
* @author Joa F$+_Z~yt3;
*/ =?FA9wm
publicclass Result { JBU
qZ
@|d|orMC
private Page page; 9k$uo_i'
{ ET+V
private List content; :;7q up
qa%g'sB-b
/** CdEJ/G:
* The default constructor B<0lif|
*/ [2&Fnmjk}X
public Result(){ ]+@b=J2b
super(); lJU[9)Q_
} i$%V)pH~F
;dPLi4=o
/** cu SXv)
* The constructor using fields A#8/:t1AW
* 'etCIl3
* @param page xNm<` Y?
* @param content Zu+Z7@$}/
*/ z6Mf>q
public Result(Page page, List content){ $
Q2|{*
this.page = page; kM9E)uT>(<
this.content = content; vWj|[| <rX
} ?[T&y
,ln
Z~]17{x0
/** zL7+HY*3o
* @return Returns the content. nR
,j1IUF
*/ ^KlMBKWyB
publicList getContent(){ =v8#@$
return content; nE/T)[1|
} t`Hwq
xpSMbX{e
/** 8ALYih7"W
* @return Returns the page. *_^AK=i
*/ nQ/El&{
public Page getPage(){ Sc*p7o: A
return page; 4Ly!:GH3T
} -bE{yT)7
5HJ6[.HO
/** f+F /`P%
* @param content wddF5EcK0
* The content to set. ? 8'4~1g`}
*/ "lUw{3
public void setContent(List content){ Va
!HcG1^:
this.content = content; ob0clJX
} f PDnkr
*;4r|#LG
/** ZA:YoiaC#
* @param page rL_AqSGAK1
* The page to set. Uh&MoIBs#
*/ 2TIZltFS0e
publicvoid setPage(Page page){ &z,w0FOre
this.page = page; fe&K2C%bm
} $TR[SMj
} tq1h1
0p~:fm
#V~r@,
bup;4~g
*S<>_R 8
2. 编写业务逻辑接口,并实现它(UserManager, c%v%U &
/Nxy?g|,
UserManagerImpl) sV{[~U,|
java代码: !d"J,. )
9ft7
*^QfTKN
/*Created on 2005-7-15*/ uTn(fs)D
package com.adt.service; 'n.ATV,
pU}>}
import net.sf.hibernate.HibernateException; -3bl!9h^
KuFDkT!
import org.flyware.util.page.Page; e;[/ytz"d'
44b'40
import com.adt.bo.Result; +[D=2&tmk
Z7Mc.[C
/** w~1K93/p!
* @author Joa LN_6>u
*/ dD!} P$
publicinterface UserManager { |\elM[G"g
wUl}x)xo
public Result listUser(Page page)throws 9jJ&QACn
x?f3XEA_
HibernateException; R$cg\DD
191O(H
} ;m7$U
~|fd=E%
8th G-
kOJs;k
!U*i13
java代码: C>t1~^Q},9
n,n]V$HFGh
py@5]n%
/*Created on 2005-7-15*/ MW`q*J`Yo
package com.adt.service.impl; X}g!Lp
^d4#
import java.util.List; <7u*OYjA
iB[%5i-
import net.sf.hibernate.HibernateException;
\6nWt6M
#*?5
import org.flyware.util.page.Page; !QP~#a%
import org.flyware.util.page.PageUtil; Fi1gM}>py
O@??
NF6G
import com.adt.bo.Result; mp!6MO Q
import com.adt.dao.UserDAO; wcB-)Ra
import com.adt.exception.ObjectNotFoundException; @[.%A;E4
import com.adt.service.UserManager; S9-K
t$R|lv5<
/** Q4q3M=0
* @author Joa bL{wCo-Y
*/ `ag>4?7?
publicclass UserManagerImpl implements UserManager { [%z~0\lu8
nv@$'uQRp
private UserDAO userDAO; "4}{Z)&R2
lhJT&
/** MS><7lk-
* @param userDAO The userDAO to set. o= N= W
*/ H?UmHwwE
publicvoid setUserDAO(UserDAO userDAO){ _T8#36iR
this.userDAO = userDAO; l9?]t;
} w6v P
a
>*{\N^:z
/* (non-Javadoc)
8X[G)J;
* @see com.adt.service.UserManager#listUser .6f
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%/-Z1Nv*#
(org.flyware.util.page.Page) q-X)tH_+w@
*/ :C_\.pA
public Result listUser(Page page)throws
O0';j!?X
4E&URl0Bh
HibernateException, ObjectNotFoundException { uZ\ >
int totalRecords = userDAO.getUserCount(); lMF j"x\
if(totalRecords == 0) L]9uY
throw new ObjectNotFoundException &
/UcFB
!+=jD3HTJ
("userNotExist"); 2*F["E
page = PageUtil.createPage(page, totalRecords); 8yA: C
List users = userDAO.getUserByPage(page); thl{IU
returnnew Result(page, users); {&,a)h7&
} TY5<hPU=
v/}M_E
} c+Ejah+
3[pA:Z+xx
[%
KBc}
W9t%:wF
`oXUVr
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 w}K<,5I>
t8E'd:pE
询,接下来编写UserDAO的代码: w J/k\
3. UserDAO 和 UserDAOImpl: Gdi1lYu6V
java代码: \[%[`m
;vc$;54K
=YR/X@&
/*Created on 2005-7-15*/ ^mm:u<Yt
package com.adt.dao; `LEk/b1(P
o{(-jhR
import java.util.List; ijw'7d|,
XTXRC$B
import org.flyware.util.page.Page; O\q|b#q}/
6,ylkf3
import net.sf.hibernate.HibernateException; %AF~Ki
[Z`q7ddd^
/** @=E@
*@g
* @author Joa H
:}|UW
*/ ;sT7c1X^!
publicinterface UserDAO extends BaseDAO { cP`o?:
DO'$J9;*
publicList getUserByName(String name)throws {k-GWYFA
Klzsr,
HibernateException; 5lu620o
d/k&f5
publicint getUserCount()throws HibernateException; Q4JwX=ZVj
=mxmJFA
publicList getUserByPage(Page page)throws =1!wep"
O{y2tz3
HibernateException; ZXsm9
7[[XNJP
} ^sY ]N77
rQC{"hS1
Mf^ ;('~
B5hk]=Ud
lY
yt8H
java代码: 4E}]>
]O3[Te
i:0~% X
/*Created on 2005-7-15*/ SWvy<f4<
package com.adt.dao.impl; ;,}tXz
+e. bO5Y
import java.util.List; yHT8I
q%i2'yE
import org.flyware.util.page.Page; 'KMyaEh.u
V7.xKmB
import net.sf.hibernate.HibernateException; 8
C @iD%
import net.sf.hibernate.Query; /v7U~i5
@[D-2s
import com.adt.dao.UserDAO; DJr{;t$7~
sNZ{OD+
/** Ouc=4'$-
* @author Joa }:P/eY
*/ dU+28
public class UserDAOImpl extends BaseDAOHibernateImpl
#lRkp.e
MYFRrcu;
implements UserDAO { YQxVeS(
J)D/w[w
/* (non-Javadoc) y)X1!3~(
* @see com.adt.dao.UserDAO#getUserByName Ho9 a#9
RNE})B
(java.lang.String) l 3bo
*/ c&z@HEzV7
publicList getUserByName(String name)throws }A;J-7g6
D'2&'7-sm\
HibernateException { s|.V:%9e
String querySentence = "FROM user in class d#cw`h<c~
6|+I~zJ88
com.adt.po.User WHERE user.name=:name"; @JVax -N
Query query = getSession().createQuery :KGUO{_u
G]X72R?g
(querySentence); #)QR^ss)iw
query.setParameter("name", name); p "EQ6_f
return query.list(); ]p~w`_3v
} }t#uSz^
eD5.*O
/* (non-Javadoc) >u?pq6;
* @see com.adt.dao.UserDAO#getUserCount() }w^Hm3Y^&
*/ g0NtM%
publicint getUserCount()throws HibernateException { T+7-6y+ d
int count = 0; :1NF#-2\f
String querySentence = "SELECT count(*) FROM E
Mq P
D&KRJQ/
user in class com.adt.po.User"; RGvfy/T
Query query = getSession().createQuery Q{1Q w'+@
Q]wM WV
(querySentence); Gv?3T Am8
count = ((Integer)query.iterate().next Y3^UJe7E
_{0'3tI7
()).intValue(); 6wK>SW)#&j
return count; tGv5pe*r
} ,xmmS\
b8Gu<Q1k
/* (non-Javadoc) [vCZoG8+>
* @see com.adt.dao.UserDAO#getUserByPage ;cKN5#7
LCKCg[D
(org.flyware.util.page.Page) SbS*z:
*/ !c+,OU[
publicList getUserByPage(Page page)throws 03Czx `
@$o.Z;83`r
HibernateException { !0i6:2nw
String querySentence = "FROM user in class g:&YSjO>G
RN2^=$'.
com.adt.po.User"; TKJs'%Q7F6
Query query = getSession().createQuery ?}p~8{ '
x~3N})T5
(querySentence); uW4)DT9[5
query.setFirstResult(page.getBeginIndex()) <!@*2/Q]J]
.setMaxResults(page.getEveryPage()); mmSC0F
return query.list(); y~eQVnH5W
} ob= ](
j~DTvWg<Jl
} *nZe|)m
2;&K*>g&.
{yj8LxX^
F_C7S
jd>ug=~x
至此,一个完整的分页程序完成。前台的只需要调用 v/ $~ifY"
(x)}k&B;
userManager.listUser(page)即可得到一个Page对象和结果集对象 8kn> ?
]{sx#|_S
的综合体,而传入的参数page对象则可以由前台传入,如果用 0<ze'FbV]
.5?e)o)
webwork,甚至可以直接在配置文件中指定。 G#uD CF,O
S=f:-?N|
下面给出一个webwork调用示例: VPC7Dh%.
java代码: MZ$x(Vcj
5f#N$mh
D^m`&asC
/*Created on 2005-6-17*/ <I
5F@pe'
package com.adt.action.user; v,}Mn7:
)~>
C1<
import java.util.List; MP
LgE.n
r$Gz
import org.apache.commons.logging.Log; m[>pv1o
import org.apache.commons.logging.LogFactory; ?b,4mDptE
import org.flyware.util.page.Page; '}$]V>/
?R!?}7
import com.adt.bo.Result; ]?un'$%e
import com.adt.service.UserService; ffH]`N
import com.opensymphony.xwork.Action; (=\))t8J
f*%Y]XL;%
/** )(/Bw&$
* @author Joa 6 d;_}
*/ c'!+]'Lr
publicclass ListUser implementsAction{ k00&+C
Jc=~BT_G
privatestaticfinal Log logger = LogFactory.getLog ##QKXSD
=JW.1;
(ListUser.class); <(E9U.
y$,j'B:;4m
private UserService userService; '=V1'I*
oF(=@UL
private Page page; xRrKrs &eE
Tfytc$aQ
privateList users; O>c2*9PM
oC
}
/* yhsbso,5 a
* (non-Javadoc) ~a ]R7X7
* qX"m"ko
* @see com.opensymphony.xwork.Action#execute() ^ZD0rp(l
*/ K&IHt?vh!
publicString execute()throwsException{ 95IR.Qfn!
Result result = userService.listUser(page); ?y|8bw<
page = result.getPage(); Aq*,cOF+
users = result.getContent(); /ReOf<%B
return SUCCESS; [+3~wpU(p
} IAFj_VWC0
08W^
/** %7SGQE#W_~
* @return Returns the page. Egm-PoPe
*/ UNhM:!A
public Page getPage(){ XJguw/[wm
return page; ,AuejMd
} _h1:{hF
rhH !-`m
/** J]gtgt^
* @return Returns the users. 15Vo_
wD<y
*/ 9oA-Swc[
publicList getUsers(){ dx)v`.%V
return users; wpepi8w,
} ?y4vHr"c
[h@MA|
/** yiAusl;
* @param page gVpp9VB
* The page to set. |7:{vA5
*/ 1g1gu=|Q
publicvoid setPage(Page page){ nOdAp4{:q%
this.page = page; jKhj 7dR
} [+
N 5
QMBV"E_aY
/**
|7wiwdD"
* @param users hZDv5]V:0
* The users to set. TM$Ek^fQ.
*/ %q5iy0~P
publicvoid setUsers(List users){ DOGg=`XK1
this.users = users; *
~4m!U_s
} 7).zed^
VsR`y]"g
/** ^`Qh*:T$
* @param userService ?Ulc`-d
* The userService to set. CJ
9tO#R
*/ -Drm4sTpDb
publicvoid setUserService(UserService userService){ a FrVP
this.userService = userService; !Knv/:+
} n:5*Tg9
} `<kV)d%xEF
(!&g (l;
wfc[B;K\
Y'S9
rXR}]|;>
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, M"$TXXe
!WReThq
可以通过配置文件来进行配置,例如,我想每页显示10条记录,那 >5!/&D.q
#pz{,
么只需要: p; ZEz<M
java代码: 3`aJ"qQE
kg_f;uk+
5`3f"(ay/
<?xml version="1.0"?> F ttny]
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork P!)k 4n
PX1Scvi
1.0//EN" "http://www.opensymphony.com/xwork/xwork- (B zf~#]~
4$+9k;m'
1.0.dtd"> FE/2.!]&o
y[!4M+jj
<xwork> e[@
^UY
8@a|~\3-
<package name="user" extends="webwork- i#~1|2
dsxaxbVj%
interceptors"> *X^__PS]
J}.y+b>8\
<!-- The default interceptor stack name q[3b i!Q
Q nqU!6k@
--> E4'D4@\W
<default-interceptor-ref V8xv@G{;
:6z0Ep"
name="myDefaultWebStack"/> m~Dq0 T
}m<)$.x|P
<action name="listUser" F*d{<
6zLz<p?
class="com.adt.action.user.ListUser"> `Vwj|[0k
<param NwG&uc+Q
/j'We-C
name="page.everyPage">10</param> 2/BFlb
<result ++13m*fA
XY|-qd}A
name="success">/user/user_list.jsp</result> ^tuJM:
</action> `4&\ %9
)vS##-[_
</package> |"P5%k#6^>
y( MF_'l
</xwork> xL>0&R
/:e|B;P`k
AX1'.
3a{QkVeV7
(>0d+ KT
!*|CIxk(
这样就可以通过配置文件和OGNL的共同作用来对page对象设置初值 %1HW
) 7
W{;!JI7;z
了。并可以通过随意修改配置文件来修改每页需要显示的记录数。 {djOU
9]
\lR~!6:
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 ^[%~cG
3 XfXMVm
@-b}iP<T
l}(~q!r
jgbw'BBu
我写的一个用于分页的类,用了泛型了,hoho fJE ki>1
lGLZIp
java代码: X\%],"9%
\k1Wh-3
Gs?W7}<$
package com.intokr.util; *=/XlSWF
2|%30i,vV
import java.util.List; KH
KqE6
{J0^S
/** uEi!P2zN
* 用于分页的类<br> e#'`I^8l
* 可以用于传递查询的结果也可以用于传送查询的参数<br> c~RIl5j
* i2j)%Gc}
* @version 0.01 iqoPD4A
* @author cheng OC>" +
*/ e2*^;&|%
public class Paginator<E> { >Le
mTr
privateint count = 0; // 总记录数 v}_$9&|S
privateint p = 1; // 页编号 95!xTf
privateint num = 20; // 每页的记录数 &e rNVD5o
privateList<E> results = null; // 结果 `\Npu
bm+ Mr
/** )nJ>kbO~8
* 结果总数 ,!Hl@(
*/ Ti)n(G9$
publicint getCount(){ cn\_;TYiJ
return count; J`mp8?;%
} Z9sg6M@s
#* Hhe>
publicvoid setCount(int count){ TRq~n7Y7C
this.count = count; A!f0AEA,
} Yr31GJ}K
#YNb&K
n
/** ,f1wN{P
* 本结果所在的页码,从1开始 ld?M,Qd
* @KpzxcEoO
* @return Returns the pageNo. VC+\RB#:-
*/ 1Jd: %+T
publicint getP(){ aH$~':[93
return p; 67g/(4 &
} dG rA18
UB1/FM4~
/** LH_ 2oJ\
* if(p<=0) p=1 2
g8PU$T
* E7<:>Uh
* @param p c1<g!Q&E
*/ ;F+%{LgKl
publicvoid setP(int p){ Rk=B;
if(p <= 0) ]@P*&FRcZ
p = 1; O>Sbb2q?"
this.p = p; b#m47yTW9<
} a9I8WQ
M,@SUu v"
/** S'O0'5U@
* 每页记录数量 8tL61x{]
*/ 6vA5L_
publicint getNum(){ cm3Y!p{p"
return num; c5;ROnTm
} \\qg2yI
}';&0p2Z
/** ?MYD}`Cv
* if(num<1) num=1 Dpd$&Wr0Y
*/ yU.0'r5uR
publicvoid setNum(int num){ >
95Cs`>d
if(num < 1) x\DkS,O
num = 1; 8zCAy@u
this.num = num; 54{"ni2a
} +Xp;T`,v
J]0#M:w&
/** %awS*
* 获得总页数 {dwV-qz
*/ l 3K8{HY
publicint getPageNum(){ 6{
Nbe=
return(count - 1) / num + 1; @_Zx'mTI
} B<LavX>F
["}A#cO652
/** fq|2E&&v
* 获得本页的开始编号,为 (p-1)*num+1 *eP4dGe&
*/ vt
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publicint getStart(){ >{S $0D
return(p - 1) * num + 1; XV>6;!=E
} c)8wO=!
DBUwf1=qj
/** SDIeq
* @return Returns the results. ?/(K7>`
*/ pL@zZK0
publicList<E> getResults(){ =T)2wcXBB
return results; |S{P`)z%f
} L{f>;[FR
Y14R"*t~
public void setResults(List<E> results){ shT[|@"C
this.results = results; Ij1]GZ`A(
} e<4z)
lM,zTNu-z
public String toString(){ wsrx|n[]
StringBuilder buff = new StringBuilder *BsDHq-F~
EcoUpiL%2
(); Jche79B
buff.append("{"); {*;]I?9Al
buff.append("count:").append(count); 0>=)
buff.append(",p:").append(p); s ;s-6%p
buff.append(",nump:").append(num); cWO
)QIE
buff.append(",results:").append _[i=TqVmf
9*;isMkq<
(results); xm|4\H&Bg
buff.append("}"); XDko{jEJ
return buff.toString(); (Dm"e`
} LGRO En<*d
z<6P3x|
} \'+{X(]
; axaZV
qTHg[sME