Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 W;q+, Io
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 gN?0m4[$i
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据这一功能,我设计了通用的抽象Bean基类和分页类支持,代码来 /xySwSmh3
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自于Quake Wang的javaeye-core包的相应类,然后又做了很多修改 -Q$b7*"z(
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分页支持类: EJLQ&oH[
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java代码: :.$"kXm^
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package com.javaeye.common.util; IaLMWoh
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import java.util.List; *69c-`o
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publicclass PaginationSupport { R&#tSL
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publicfinalstaticint PAGESIZE = 30; zDDK
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privateint pageSize = PAGESIZE; BwxnDe G)
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privateList items; V^n0GJNo
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privateint totalCount; QU/fT_ORw
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privateint[] indexes = newint[0]; QHzgy?
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privateint startIndex = 0; >)Gd:636+
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public PaginationSupport(List items, int F;u_7OM
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totalCount){ l~J*' m2
setPageSize(PAGESIZE); IU#x[P!
setTotalCount(totalCount); 5ZK&fKeCF
setItems(items); d~@q%-`lA
setStartIndex(0); Zu21L3
} s+,&|;Q
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public PaginationSupport(List items, int ^ve14mbF#.
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totalCount, int startIndex){ tnb$sulc+
setPageSize(PAGESIZE); .9h)bf+
setTotalCount(totalCount); *Qkc[XHqy
setItems(items); =eBmBn
setStartIndex(startIndex); 3b!,D
} gnLn7?
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public PaginationSupport(List items, int SEM8`lnu
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totalCount, int pageSize, int startIndex){ .Evy_o\^
setPageSize(pageSize); 6~8F!b2
setTotalCount(totalCount); eLfvMPVo
setItems(items); nt ,7u(
setStartIndex(startIndex); *1^$.Q&
} -M4p\6)Ge
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publicList getItems(){ 30Drrno7Io
return items; dE5D3ze
} xAhxD|4_
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publicvoid setItems(List items){ CQ^3v09N;~
this.items = items; E0 l_--
} qZk:mlYd
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publicint getPageSize(){ =X(%Svnp
return pageSize; t6lE#<xZV;
} n~g LPHY
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publicvoid setPageSize(int pageSize){ \9:wfLF8!
this.pageSize = pageSize; TDNf)Mm
} '6-$Xq0^E
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publicint getTotalCount(){ $_D6_|HK
return totalCount; 6f)2 F<
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} v]"L]/"
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publicvoid setTotalCount(int totalCount){ #sB,1"
if(totalCount > 0){ edvFQ#,d
this.totalCount = totalCount; 7J*N_8?2
int count = totalCount / ?+2b(2&MXE
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pageSize; '#\1uXM1U?
if(totalCount % pageSize > 0) h<6UC%'ac
count++; 2/7_;_#vJ%
indexes = newint[count]; TgfrI
for(int i = 0; i < count; i++){ \Kavw
indexes = pageSize * $uh z
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} 4Ysb5m)u
}else{ 3x@<Z68S
this.totalCount = 0; OB-Q /?0
} Dg>^A
} =!b6FjsiG
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publicint[] getIndexes(){ LM)`CELsYc
return indexes; aM=D84@
} ?GT@puJS-
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publicvoid setIndexes(int[] indexes){ [A2`]CE<@
this.indexes = indexes; (Ddp|a"b
} .12aUXo(
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publicint getStartIndex(){ w:i:~f .
return startIndex; )?aaBaN$
} Q<(YP.k
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publicvoid setStartIndex(int startIndex){ Uh6 '$0
if(totalCount <= 0) &^".2)zU
this.startIndex = 0; O;9?(:_
elseif(startIndex >= totalCount) ExBUpDQc
this.startIndex = indexes 8wZf]_
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[indexes.length - 1]; 2 QTZwx
elseif(startIndex < 0) wBSQ:f]g
this.startIndex = 0; 3gZ8.8q3
else{ 3_$w|ET
this.startIndex = indexes jXg
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[startIndex / pageSize]; IE2"rQ T
} .)tSg
} ]T:;Vo
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publicint getNextIndex(){ J^#:qk
int nextIndex = getStartIndex() + ]< l6s
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pageSize; PmpNAVE'
if(nextIndex >= totalCount) z+{,WHjo
return getStartIndex(); / |r'
else uQ1@b-e`5
return nextIndex; o{:xp r=(
} |*5 =_vF
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publicint getPreviousIndex(){ u+m,b76
int previousIndex = getStartIndex() - :mppv8bh
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pageSize; )u%je~Vw
if(previousIndex < 0) "SxLN
8.:
return0; K>Fqf
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else K5>p89mZ
return previousIndex; 2}6%qgnT-
} l |2D/K5
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} /1UOT\8U
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抽象业务类 2F{hg%
java代码: Ex amD">T
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/** {$D,?V@%_
* Created on 2005-7-12 *iO u'
*/ (& "su3z
package com.javaeye.common.business; hXIro
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import java.io.Serializable; 3rW|kkn
import java.util.List; 'NjzgZ~]P
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import org.hibernate.Criteria; +d}E&=p_
import org.hibernate.HibernateException; kl!wVLE
import org.hibernate.Session; O|IG_RL]
import org.hibernate.criterion.DetachedCriteria; BF*kb2"GZ6
import org.hibernate.criterion.Projections; \uqjs+
import tsOrt3
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org.springframework.orm.hibernate3.HibernateCallback; 1J=.N|(@Q
import (/d5UIM{&
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org.springframework.orm.hibernate3.support.HibernateDaoS ?liK\C2Z<
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upport; r`y ezbG
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import com.javaeye.common.util.PaginationSupport; >2$5eI
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public abstract class AbstractManager extends J?@DGp+t
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HibernateDaoSupport { EKEjv|_)
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privateboolean cacheQueries = false; ZX!r1*c
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privateString queryCacheRegion; h!~3Dw>,N
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publicvoid setCacheQueries(boolean 3`d}~v{
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cacheQueries){ s^0/"j |7
this.cacheQueries = cacheQueries; qf@q]wtar
} 8KB>6[H!wE
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publicvoid setQueryCacheRegion(String 4(e59ZgY
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queryCacheRegion){ FMNm,O]
this.queryCacheRegion = )[H{yQ
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queryCacheRegion; ;AR{@Fu.
} ~\ ,w {
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publicvoid save(finalObject entity){ F|Mi{5G%
getHibernateTemplate().save(entity); ZUz ^!d
} Re:jVJgBz
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publicvoid persist(finalObject entity){ 7{e{9QbJ4
getHibernateTemplate().save(entity); LTNj| u
} 3!Sp0P
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publicvoid update(finalObject entity){ iHwLZ[O{
getHibernateTemplate().update(entity); /MY9
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} z,qRcO&
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publicvoid delete(finalObject entity){ $vHU$lZ/W
getHibernateTemplate().delete(entity); Zfk*HV#\
} R1nJUOE4w^
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publicObject load(finalClass entity, R>DaOH2K*
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finalSerializable id){ [A}rbD K
return getHibernateTemplate().load Q-ni|
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(entity, id); b'VV'+|
} {o5V7*P;_
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publicObject get(finalClass entity, O^/Maa/D1
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finalSerializable id){ A7(hw~+@
return getHibernateTemplate().get u` oq(?|
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(entity, id); ?)bS['^1)
} |mdi]TL
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publicList findAll(finalClass entity){ kb[P\cRa
return getHibernateTemplate().find("from [:xiZ
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" + entity.getName()); KIR'$ 6pn~
} f;/QJ
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publicList findByNamedQuery(finalString /Q,{?';~
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namedQuery){ kYzC#.|1
return getHibernateTemplate 66^ycZCH
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().findByNamedQuery(namedQuery); zBO(`=|
} D:Q
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publicList findByNamedQuery(finalString query, ,J`'Y+7W
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finalObject parameter){ d
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return getHibernateTemplate .{;Y'Zc14S
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().findByNamedQuery(query, parameter); nXjPx@
} gN)c
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publicList findByNamedQuery(finalString query, e/->_T(I
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finalObject[] parameters){ Lm@vXgMD
return getHibernateTemplate 9f\/\L
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().findByNamedQuery(query, parameters); 5,)Qw
} =)hVn
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publicList find(finalString query){ O?<&+(uMTT
return getHibernateTemplate().find _EF&A-kX|u
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(query); j5
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} '#(v=|J
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publicList find(finalString query, finalObject aZEn6*0B
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parameter){ [F5h
return getHibernateTemplate().find ""s]zNF}
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(query, parameter); ' B
} PMfkA!.Y
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public PaginationSupport findPageByCriteria lN9=TxH1(;
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(final DetachedCriteria detachedCriteria){ c5|:,wkx
return findPageByCriteria "B_K
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); V/LQ<Yke
} QdLYCR4f
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public PaginationSupport findPageByCriteria %lg=YGLQB
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(final DetachedCriteria detachedCriteria, finalint G;f/Tch
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startIndex){ d|T!v
return findPageByCriteria gocrjjAHk
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(detachedCriteria, PaginationSupport.PAGESIZE, QXF
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startIndex); WcC?8X2
} ZNYH#mJX*
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public PaginationSupport findPageByCriteria E9V5$
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(final DetachedCriteria detachedCriteria, finalint mrV!teP
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pageSize, "bDs2E+W
finalint startIndex){ d~h:~
return(PaginationSupport) >a3p >2
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getHibernateTemplate().execute(new HibernateCallback(){ >J u]2++lx
publicObject doInHibernate :_Eqf8T
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(Session session)throws HibernateException { pIbdN/z
Criteria criteria = wO2_DyMm@
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detachedCriteria.getExecutableCriteria(session); $ "Bh]-
int totalCount = pHoEa7:
(|wz7AY2
((Integer) criteria.setProjection(Projections.rowCount R0oKbs{
:{(w3<i
()).uniqueResult()).intValue(); G|\^{5
criteria.setProjection f<A5?eKw
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(null); Gn;@{x6
List items = &CwFdx:Ff
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criteria.setFirstResult(startIndex).setMaxResults N25V]
;;A2!w{}[i
(pageSize).list(); 97)/"i e
PaginationSupport ps = m[k_>e\u
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new PaginationSupport(items, totalCount, pageSize, ?'"X"@r5
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startIndex); TNJG#8 n%Y
return ps; MQKfJru7
} |pa$*/!NT
}, true); uytE^
} Et_V,s<|
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public List findAllByCriteria(final /t-fjB{=G
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DetachedCriteria detachedCriteria){ Hi]cxD*`
return(List) getHibernateTemplate mw5?[@G-
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().execute(new HibernateCallback(){ h_d<!
publicObject doInHibernate CkswJ:z)sc
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(Session session)throws HibernateException { F7")]q3I~
Criteria criteria = ;O<9|?
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detachedCriteria.getExecutableCriteria(session); "`[!L z
return criteria.list(); tTU=+*Io
} P9T5L<5
}, true); .Yw'oYnS
} F ]O$(7*
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public int getCountByCriteria(final 1wW)tNKIF
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DetachedCriteria detachedCriteria){ &QNWL]
Integer count = (Integer) i_][PTH
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getHibernateTemplate().execute(new HibernateCallback(){ dJ?XPo"Cm=
publicObject doInHibernate
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(Session session)throws HibernateException { 7H>@iI"?
Criteria criteria = n[YEOkiG
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detachedCriteria.getExecutableCriteria(session); :iR \%
return ~8aJ S,u
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criteria.setProjection(Projections.rowCount nL:SG{7
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()).uniqueResult(); fIGFHZy,
} e|4&b@
}, true); *._|- L
return count.intValue(); Dup;e&9g
} .d/:30Y
} PQ|69*2G
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用户在web层构造查询条件detachedCriteria,和可选的 %zU`XVNN+
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 <}6{{&mT4
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PaginationSupport的实例ps。 -CH`>
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ps.getItems()得到已分页好的结果集 wW?,;B'74
ps.getIndexes()得到分页索引的数组 XBQ\_2>
ps.getTotalCount()得到总结果数 #"fJa:IYG7
ps.getStartIndex()当前分页索引 ob_I]~^I?|
ps.getNextIndex()下一页索引 fIF<g@s
ps.getPreviousIndex()上一页索引 r}yG0c,
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 $(Ugtimdv
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,尤其是上面的示例代码,让我着实觉得该对我原来的分页查询做 /WPv\L
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一下代码重构了。 4lKVY<
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我把原本我的做法也提供出来供大家讨论吧: l<(Y_PE:
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首先,为了实现分页查询,我封装了一个Page类: v&FF|)$
java代码: w#i[_
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/*Created on 2005-4-14*/ ~"Gf<3^y+
package org.flyware.util.page; d7Ur$K\=y
1xf=_F0`&
/** \n0Oez0z!B
* @author Joa A~nf#(!^]
* 56hA]O29O
*/ NvjJb-u
publicclass Page { ?t@v&s
B~'MBBD"
/** imply if the page has previous page */ 0:KE@=
privateboolean hasPrePage; e$c?}3E!z
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/** imply if the page has next page */ N?dvuB
privateboolean hasNextPage; {5*|C-WWtG
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/** the number of every page */ 8&"(WuZ@
privateint everyPage; t]1ubt2W
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/** the total page number */ ^5=UK7e5KY
privateint totalPage; 4\.V
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/** the number of current page */ *s}|Hy
privateint currentPage; o
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/** the begin index of the records by the current J` {6l
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query */ Bqws!RM'&@
privateint beginIndex; y'ja< 1I>
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/** The default constructor */ y%]8'q$
public Page(){ a=GM[{og
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} A{o 'z_zC
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/** construct the page by everyPage $N$ FtpB
* @param everyPage 1-I
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* */ *5%*|>
public Page(int everyPage){ D}Ilyk_uUw
this.everyPage = everyPage; F="z]C;u
} V%HS\<$h
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/** The whole constructor */ 7dh1W@\
public Page(boolean hasPrePage, boolean hasNextPage, ~$O1`IT
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int everyPage, int totalPage, BdbJ< Is
int currentPage, int beginIndex){ FqA3{
this.hasPrePage = hasPrePage; D
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this.hasNextPage = hasNextPage; sPNfbCOz
this.everyPage = everyPage; (g :p5Rl
this.totalPage = totalPage; M/V(5IoP(
this.currentPage = currentPage; $mco0%$
this.beginIndex = beginIndex; zvv:dC/p<
} )He#K+[}^4
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/** %R0v5=2'
* @return qUhRu>
* Returns the beginIndex. .
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*/ KiLvI,9y
publicint getBeginIndex(){ ;~HNpu$
return beginIndex; 1H:ea7YVU
} oL/o*^
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/** Tc
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* @param beginIndex E(+T*
* The beginIndex to set. )&W|QH=AI
*/ ^>~dlS
publicvoid setBeginIndex(int beginIndex){ !^U6Z@&/R
this.beginIndex = beginIndex; {j(4m
} X7aXxPCq1
6(56,i<#/
/** OsW"CF2
* @return TW`mxj_J2
* Returns the currentPage. g jG2
*/ mp`PE=
publicint getCurrentPage(){ O{KB0"s>i
return currentPage; D#sf i,O
} ~] =?b)B
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/** t\5c@j p
* @param currentPage ~
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* The currentPage to set. {ctwo X[;
*/ #t71U a
publicvoid setCurrentPage(int currentPage){ RJJ1
this.currentPage = currentPage; {KaN,td9
} d
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/** xi {|
* @return }F{=#Kqn^
* Returns the everyPage. &>}.RX]t
*/ ;cSGlE |
publicint getEveryPage(){ :B#EqeI
return everyPage; y~#\#w{
} ZW ye>]
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/** %= u/3b:o
* @param everyPage Rlg#z4m
* The everyPage to set. j)D-BK&+
*/ 4e%8D`/=M
publicvoid setEveryPage(int everyPage){ ^E@@YV
this.everyPage = everyPage; '_Wt}{h
} #MTj)P,
5}<[[}(
/** %<U{K;
* @return nlfPg-78B+
* Returns the hasNextPage. 4UCwT1
*/ nTZ> |R)
publicboolean getHasNextPage(){ S!j^|!
return hasNextPage; wkT;a&_
} J9@}DB
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/** !P|5#.eC
* @param hasNextPage IhW7^(p\
* The hasNextPage to set. L~MpY{!3
*/ Y$8; Gm<)
publicvoid setHasNextPage(boolean hasNextPage){ N~g%wf@w
this.hasNextPage = hasNextPage; ?:}Pa<D&K
} _@prmSc
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/** Zd<[=%d
* @return R#0{Wg0O)
* Returns the hasPrePage. ,+-? Zv 2
*/ k/#M<z
publicboolean getHasPrePage(){ aW`dFitpM
return hasPrePage; a>b8-j=J
} [-VGArD[k,
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/** E/"SU*Co
* @param hasPrePage ``-k{C#F
* The hasPrePage to set. ^g]xU1] *
*/ =x4a~=HX
publicvoid setHasPrePage(boolean hasPrePage){ v' 0!= r
this.hasPrePage = hasPrePage; :VFTVmr
} b?k4InXh
a%n'%*0
/** I<`V_
* @return Returns the totalPage. >ITEd
* nO_!:6o".
*/ }N| \
publicint getTotalPage(){ 5Bd(>'ig_
return totalPage; WD;)VsP
} D Q 5W6W
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/** J9a $AU*
* @param totalPage {5 Kz' FT
* The totalPage to set. Qtnv#9%Vi
*/ EW;1`x
publicvoid setTotalPage(int totalPage){ ;.0LRWcJ
this.totalPage = totalPage; 3uO8v{`
} [0op)Kn
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} a>(~ C'(<
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sS'{QIRC'
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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 ]-EN/V
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个PageUtil,负责对Page对象进行构造: \4@a
java代码: 'RQiLUF
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/*Created on 2005-4-14*/ @SQceQfB
package org.flyware.util.page; R_9 o!sTZ
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import org.apache.commons.logging.Log; S| "TP\o
import org.apache.commons.logging.LogFactory; PHl4 vh#E!
uH]
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/** GDmv0V$6
* @author Joa ]gHLcr3
* w<mqe0
*/ VwC4QK,d;
publicclass PageUtil { fr]Hc+7
UhBz<>i;!
privatestaticfinal Log logger = LogFactory.getLog 'v+96b/;
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(PageUtil.class); *cQz[S@F
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/** m>O2t-
* Use the origin page to create a new page ZZwBOGVU
* @param page >E~~7Yal
* @param totalRecords g6`.qyVfz'
* @return bx]14}6
*/
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publicstatic Page createPage(Page page, int G
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R{ 4u|A?9
totalRecords){ (Otur
return createPage(page.getEveryPage(), g!\QIv1D
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page.getCurrentPage(), totalRecords); _&=9 Ke
} ? 9qAe
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/** X)y*#U
* the basic page utils not including exception J:[3;Z
@NBXyC8,Z
handler 8m \;P
* @param everyPage gi
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* @param currentPage Yr:>icz|
* @param totalRecords qm~Kw!kV
* @return page " _mmR
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*/ w[|y0jtw
publicstatic Page createPage(int everyPage, int hPS/CgLq
}0krSzcn#,
currentPage, int totalRecords){ EtPgzw[#c9
everyPage = getEveryPage(everyPage); =$[W,+X6f
currentPage = getCurrentPage(currentPage); cUYX1a)8
int beginIndex = getBeginIndex(everyPage, ?9CIWpGjU
pM,#wYL
currentPage); zcZ^s v>
int totalPage = getTotalPage(everyPage, z{AM2Z
"^!j5fZ
totalRecords); % ghJ*iHR
boolean hasNextPage = hasNextPage(currentPage, td%Y4-+ -
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totalPage); ;Xz(B4 N~o
boolean hasPrePage = hasPrePage(currentPage); aTi0bQW{
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returnnew Page(hasPrePage, hasNextPage, <'VA=orD
everyPage, totalPage, /^NJ)9IB
currentPage, x={kjym L
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beginIndex); Sw/J+FO2
} A<]&JbIt
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privatestaticint getEveryPage(int everyPage){ OrzM
hQaf
return everyPage == 0 ? 10 : everyPage; L/c4"f|.*v
} 3KR2TcT#{
|:{g?4Mi
privatestaticint getCurrentPage(int currentPage){ hLCsQYNDU
return currentPage == 0 ? 1 : currentPage; O#A8t<f|M
} 0,+EV,
"Fo
privatestaticint getBeginIndex(int everyPage, int rE9Ta8j6
.Ydr[
currentPage){ @<0h"i
x
return(currentPage - 1) * everyPage; $HP/cKu
} 5^bh.uF
3KB|NS
privatestaticint getTotalPage(int everyPage, int V,`!rJ
~D$#>'C#
totalRecords){ 9T?~$XlX
int totalPage = 0; wA{*W>i
r{bgTG
if(totalRecords % everyPage == 0) ?L`MFR
totalPage = totalRecords / everyPage; V}j%gy`
else "tEj`eR
totalPage = totalRecords / everyPage + 1 ; \z&03@Sw
J{aQ1)
return totalPage; tvGg@Xs\
} hqdC9?\
`8.1&fBr
privatestaticboolean hasPrePage(int currentPage){ >|y>e{P
return currentPage == 1 ? false : true; XL{{7%j
} "v*oga%
^U R-#WaQ
privatestaticboolean hasNextPage(int currentPage, gNG0k$nP
vsOdp:Yp9!
int totalPage){ eV@4VxaZ
return currentPage == totalPage || totalPage == `M towXj
g|_HcaW
0 ? false : true; z0EjIYI[N
} #p']-No
L{4),65
f$~ _FX
} {ILp[&sL
\HBVNBY
"it`X
B.
UwvGr h
*##QXyyg
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 *C[4 (DmB
ez{P-qB
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 Lg\8NtP
#RCZA4>
做法如下: O7Y
P_<,#
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 tg4LE?nv
V'Sd[*
的信息,和一个结果集List: t?pIE cl
java代码: B<vvsp\X
OqAh4qa,$
m70`{-O
/*Created on 2005-6-13*/
hg<"Yg=
package com.adt.bo; yf0vR%,\
5i}CzA96
import java.util.List; 4i ~eTb
r{;VTQ
import org.flyware.util.page.Page; ~*,Ddwr0a
]j%*"V
/** DctX9U(
* @author Joa x9FLr}e
*/ /h.:br?M#P
publicclass Result { ~Hp#6+
A)O_es2
private Page page; M6o
xtt4
4eDmLC"Y
*
private List content; =!I8vQ>
u&?yPR
/** b<29wL1
* The default constructor F``EARG)iu
*/ /6i Tq^.%
public Result(){ Mm:a+T
super(); 2
} 0{^l2?mgSb
L@d]R MNv
/** Q{ |+3!!'
* The constructor using fields -$sl!%HO%
* K#m\qitb
* @param page iMOPD}`IX
* @param content bn<I#ZH2
*/ xr7-[)3Q$
public Result(Page page, List content){ 8M".o n
this.page = page; i"2J5LLv
this.content = content; @M1yBN
} &Cx yP_
2Q`PUXj
/** 14@q $}sf
* @return Returns the content. DRKc&F6Qy
*/ =Ov;'MC
publicList getContent(){ o}r!qL0c
return content; ~x+:44*
} eE#81]'6a
!DY2{Wb
/** gnKU\>2k
* @return Returns the page. rS,*s'G
*/ (F4d Fh
public Page getPage(){ [7SI<xkv
return page; ?-(w][MT\
} flm,r<*}
P@! Q1pr
/** 4:%El+,_Y
* @param content i"r.>X'Z
* The content to set. O;&yA<
*/ RpaA)R,
public void setContent(List content){ M rH%hRV6R
this.content = content; qw
Kh,[]
} gOES2
4$2
g# 9*bF
/** K\Y6
cj
* @param page rH}Dt@
* The page to set. 7Dx .;
*/ |RvpEy76
publicvoid setPage(Page page){ $fj"*
this.page = page; Hjo:;s
} RJ`/qXL
} ]ukj]m/@
JJbM)B@-
Q%AS;(d
2\iD;Z#gM
v0H>iKh7
2. 编写业务逻辑接口,并实现它(UserManager, 1VPN#Q!
Tg{dIh.Q~O
UserManagerImpl) n)wpxR
java代码: #IL~0t
)n3biQL_
4%c7#AX[T
/*Created on 2005-7-15*/ B9;,A;E};
package com.adt.service; 9cw4tqTm
=Y=^]ayO/
import net.sf.hibernate.HibernateException; [<3Q$*Ew
EiIFVP
import org.flyware.util.page.Page; B#Oc8`1Y
d@q t%r3;
import com.adt.bo.Result; ui#1 +p3G
S9ak '
/** 9{]r+z:
* @author Joa ay7+H7^|hZ
*/ *{D:1S
publicinterface UserManager { ]=
QCCC
+_|cZlQ&
public Result listUser(Page page)throws H $qdU!c
_>:=<xyOq
HibernateException; }mT%N eS
aBA#\eV
} (1r>50Ge
\ /X!tlwxh
WHD/s
w]+BBGYQKb
?` ZGM
java代码: ZC\.};.
"ppb%=
y8(?:#ZC
/*Created on 2005-7-15*/ ,ex(pmZ;
package com.adt.service.impl; 2zr WR%B
w\8rh\Mvh
import java.util.List; Y[8co<p
'm p{O
import net.sf.hibernate.HibernateException; .5Z@5g`
3vGaT4TDx
import org.flyware.util.page.Page; U*+!w@
.
import org.flyware.util.page.PageUtil; !A^w6Q;`V
2O)Kn
q
import com.adt.bo.Result; 'y@ 2,9v
import com.adt.dao.UserDAO; m*Lv,yw %a
import com.adt.exception.ObjectNotFoundException; `))J8j"
import com.adt.service.UserManager; KlX |PQ
cwD*>[j
/** t%YX-@
* @author Joa YvP"W/5
*/ o!_; H}pq
publicclass UserManagerImpl implements UserManager { Q j~W-^/ -
qu~"C,
private UserDAO userDAO; LXEu^F~{u#
0 c'2rx
/** H/la'f#o%
* @param userDAO The userDAO to set. O
|I:[S},
*/ m&jt[
publicvoid setUserDAO(UserDAO userDAO){ dgqJ=+z 0y
this.userDAO = userDAO; ^9V8 M9
} &+r
;>
`GN5QLg#}0
/* (non-Javadoc) GHsdLe=t0#
* @see com.adt.service.UserManager#listUser +nyN+X34B
y8WXp_\
(org.flyware.util.page.Page) `::(jW.KO
*/ IOES3
public Result listUser(Page page)throws g#<?OFl
=
]HJa
HibernateException, ObjectNotFoundException { ZzaW@6LJF
int totalRecords = userDAO.getUserCount(); <IkD=X
if(totalRecords == 0) rpP+20 v
throw new ObjectNotFoundException wk
<~Y 3u
^VYZ%
("userNotExist"); 9C'+~<l
page = PageUtil.createPage(page, totalRecords); H=SMDj)s+
List users = userDAO.getUserByPage(page); :x5o3xE
returnnew Result(page, users); Pv$"DEXA2
}
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]=XL9MI
} @_:?N(%(
v&/-&(+
,xM*hN3A
3'@jRK
>U
Ich
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 ~Wd8>a{w
hD.wKX?oO
询,接下来编写UserDAO的代码: ?j$8Uy$$
3. UserDAO 和 UserDAOImpl: Q_h+r!b
java代码: (=/L#Yg_
ScmzbDu
ia.B@u1/
/*Created on 2005-7-15*/ [&}<!:9'
package com.adt.dao; ;%.k}R%O@
^WYG?/{4
import java.util.List; EjCzou
2
]6u
Be
import org.flyware.util.page.Page; 2X|jq4
JRs[%w`kD
import net.sf.hibernate.HibernateException; uC ;PP=z
q@yabuN@,j
/** _I"<?sh3
* @author Joa k.f:nv5JO
*/ iP\&fZY_
publicinterface UserDAO extends BaseDAO { I8wVvs;k
N0KRND
publicList getUserByName(String name)throws ?U[nYp}"v
$W]guG
HibernateException; (dnc7KrM
K]Cs2IpI
publicint getUserCount()throws HibernateException; iK0J{'
3T^dgWXEG
publicList getUserByPage(Page page)throws wbKBwI5w
F&j|Y>m
HibernateException; ^7<m lr
l]=$<
} EF{'J8AQ
<g1hdF0
yFtf~8s3
T:5%sN;#O
siZ_JJW
java代码: L. ?dI82c
gx
R|S
W
9MZ
/*Created on 2005-7-15*/ m&c(N
package com.adt.dao.impl; Olh-(u:9+O
mK&9p{4#U
import java.util.List; 6HQwL\r79
A{T@O5ucj
import org.flyware.util.page.Page; m|gd9m$,?
JJ06f~Iw[
import net.sf.hibernate.HibernateException; A{"t0Ai='0
import net.sf.hibernate.Query; 9 9BK/>R
@a3v[}c*
import com.adt.dao.UserDAO; SytDo (_=W
&Y2P! \\2
/** -zkL)<7
* @author Joa ``CADiM:S
*/ vK~KeZ\,p=
public class UserDAOImpl extends BaseDAOHibernateImpl 4?uG> ;V
pC
Is+1O/
implements UserDAO { !sWBj'[>
2{:
J1'pC
/* (non-Javadoc) )f&]H}
* @see com.adt.dao.UserDAO#getUserByName 70(?X/5#
Av4E?@R
(java.lang.String) l~c>jm8.
*/ e!'u{>u
publicList getUserByName(String name)throws (19<8a9G
u6d~d\
HibernateException { 4=cq 76
String querySentence = "FROM user in class YIqfGXu8
^PpFI
com.adt.po.User WHERE user.name=:name"; BVeNK=7m%
Query query = getSession().createQuery k;X1x65uP
zwK;6&(W
(querySentence); K7Tell\`
query.setParameter("name", name); JPKZU<:+V
return query.list(); GQWTQIl]
} d'D\#+%>=
?"u-@E[m
/* (non-Javadoc) Ux]@prA q
* @see com.adt.dao.UserDAO#getUserCount() 1yc@q8
*/ E.9k%%X]
publicint getUserCount()throws HibernateException { |/Z)?
int count = 0; p8J"%Jq}
String querySentence = "SELECT count(*) FROM 8"^TWzg}L
c17==S
user in class com.adt.po.User"; )uWNN"
Query query = getSession().createQuery 3f8Z?[Bb@
d69VgLg
(querySentence); L@GD$F=<0
count = ((Integer)query.iterate().next KK|Jach
OUMr}~/
()).intValue(); l))IO`s=_
return count; 63$m& ]x
} essW,2,rjC
;Bi{;>3
/* (non-Javadoc) ?Qk#;~\yB
* @see com.adt.dao.UserDAO#getUserByPage )CQ}LbX Zy
3Re\ T
(org.flyware.util.page.Page) Ev#aMK
*/ . %7A7a
publicList getUserByPage(Page page)throws 4f,x@:Jw
PCjY,O
HibernateException { n3,wwymQ
String querySentence = "FROM user in class gu&oCT
ij5YV3
com.adt.po.User"; KR0
x[#.*
Query query = getSession().createQuery %Ski5q
H:6$)#
(querySentence); 0k [6
query.setFirstResult(page.getBeginIndex()) nsk
6a
.setMaxResults(page.getEveryPage()); R0'EoX
return query.list(); ?>&Zm$5V
} s6uAF(4,
Cn '=_1p
} U 7?ez
pXa? Q@6
N3) v,S-
~G:7*:[b
"-%H</
至此,一个完整的分页程序完成。前台的只需要调用 |&vuK9q
o5R40["
userManager.listUser(page)即可得到一个Page对象和结果集对象 U)8]pUI+/P
O1,[7F.4g
的综合体,而传入的参数page对象则可以由前台传入,如果用 lX3h'h
|e>-v
webwork,甚至可以直接在配置文件中指定。 ~O-8 h0d3
=oJiNM5_u
下面给出一个webwork调用示例: X3yr6J[ ^
java代码: gG>>ynn
AF6'JxG7
ba13^;fm#
/*Created on 2005-6-17*/ H=C;g)R
package com.adt.action.user; P+h&tXZn8
67?5Cv
import java.util.List; G]CY3xw98
H;1}Nvvd
import org.apache.commons.logging.Log; ;\N*iN#K
import org.apache.commons.logging.LogFactory; $EF@x}h:A
import org.flyware.util.page.Page; d.A0(*k,
M-Bw9`#Jw
import com.adt.bo.Result; ~JpUO~i/
import com.adt.service.UserService; #C^m>o~R
import com.opensymphony.xwork.Action; Q
# gHD
X $f%Ss
/** .EO1{2=
* @author Joa L8ke*O$
*/ q0wVV
publicclass ListUser implementsAction{ (6nw8vQ
HenJlo
privatestaticfinal Log logger = LogFactory.getLog ~@lNBF
F04Etf
2k
(ListUser.class); R8l9i2
xJCpWU3wM
private UserService userService; xTT>3Fj
xFZq6si?
private Page page; s? Kn,6Y
}T,uw8?f!
privateList users; ZtVa*xl
O [/~V=
/* gZ3!2T>
* (non-Javadoc) <=Qk^Y2k
* %L3]l
* @see com.opensymphony.xwork.Action#execute() Pp2)P7
*/ N;Bal/kd2
publicString execute()throwsException{ 'Nh^SbD+_|
Result result = userService.listUser(page); bd4q/w4q
page = result.getPage(); .+>}},
users = result.getContent(); x<(h9tB
return SUCCESS; /V&Y@j
} kN)ev?pQ[
~6tY\6$9f
/** YbKW;L&Ff
* @return Returns the page. a0R]hENC
*/ 1*fA>v
public Page getPage(){ RulIzv
return page; (yfTkBy
} q<VhP2R
C7#$s<>TO
/**
cO:x{~
* @return Returns the users. {\B!Rjt[T
*/ %[J( ,rm
publicList getUsers(){ |{
kB`
return users; q`P:PRgM
} `f'P
<mN3:G
/** iX=*qiVX
* @param page Qxwe,:
* The page to set. 5WUrRQ?E
*/ C7{w I`~
publicvoid setPage(Page page){ x+pFu5,
this.page = page; Ero3A'f
} o#i{/#oF
=u(fP" |{
/** yFSL7`p+
* @param users ^|Y!NHYH$Z
* The users to set. -LyIu#
*/ ze-iDd_y
publicvoid setUsers(List users){ T1E{NgK
this.users = users; L" o6)N
} ]9' \<uR
rhrlEf@
/** ]Uu/1TTf
* @param userService |fUSq1//
* The userService to set. y{&,YV&_h
*/ nMhc3t
publicvoid setUserService(UserService userService){ .NKN2
this.userService = userService; 4:.M*Dz
} <x/&Ml+
} @:63OLlrG
G.Q+"+*^
8PQt8G.
/W9=7&R0
<XNLeJdY
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, y.zW>Mfl
{}z7N~
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 r*
U6govky
Z1Wra-g
么只需要: CV k8MA
java代码: B4 hR3%
0^+W"O
1WU-gQki!
<?xml version="1.0"?> y3x_B@}BY
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork w^~,M3(+)1
=6Z1yw7s
1.0//EN" "http://www.opensymphony.com/xwork/xwork- [lf[J&}X
m\(a{x
1.0.dtd"> w"~T5%p
hYLu
<xwork> ]?^mb n
,q4 Y
N-3
<package name="user" extends="webwork- D3]_AS&\
W|:WAxJ*d
interceptors"> QZX+E
WDcjj1`l
<!-- The default interceptor stack name ~Y{K^:wN^
~%]+5^Ka]
--> O_~\$b
<default-interceptor-ref v"`w'+
sS._N@f
name="myDefaultWebStack"/> 7j^,4;
.m
.v$(
<action name="listUser" '`S,d[~
^Oo%`(D?
class="com.adt.action.user.ListUser"> hGsYu )
<param },l3N K
}q^CR(h (R
name="page.everyPage">10</param> |.YL2\
<result J(0c#}d
2?&h{PA+
name="success">/user/user_list.jsp</result> ;aSEv"iWX
</action> K#>B'>A\
gD-<^Q-
</package> xu3qX"
Ra/S46$
</xwork> Ta_#Rg*!
T!8,R{V]4
*cf#:5Nl
SO|$X
p?5zwdX+`
"_lSw3
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 ?Pa5skqR
I'JFt>]
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。 `U(FdT
kxh
$R>
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 KcHW>IBxdv
yovC~
2TdcZ<k}J
-LUKYGBK
/)j:Y:5
我写的一个用于分页的类,用了泛型了,hoho {a(TT)d
$. Ih-
java代码: {<V{0
s%
[5H#ay
m}rUc29cS,
package com.intokr.util; XOU
9r(
4h-tR
import java.util.List; {D$+~lO
8RB\P:6h
/** Bx)4BPaN
* 用于分页的类<br> opd^|xx0
* 可以用于传递查询的结果也可以用于传送查询的参数<br> ?e0ljx;
* F&^u1RYz
* @version 0.01 vLq_l4l
* @author cheng (<|,LagTuc
*/ 3:s!0ty"
public class Paginator<E> { O.i.<VD7
privateint count = 0; // 总记录数 C1hp2CW$5/
privateint p = 1; // 页编号 #>}cuC@
privateint num = 20; // 每页的记录数 !IcPO
privateList<E> results = null; // 结果 H>%K}Fh
Pa+%H]vB
/** {;q
zz9 |
* 结果总数 "d%o%
*/ Lc=t,=OhGe
publicint getCount(){ 51xiX90D
return count; U<K)'l6#2n
} c1Skt
=nGgk}Z
publicvoid setCount(int count){ ,XU<2jv]
this.count = count; H>X:#xOA_
} 1
Qln|b8<
zt6GJz1q
/** )1N~-VuT
* 本结果所在的页码,从1开始 Dr)B0]KG
* ',P$m&z
* @return Returns the pageNo. OQ&l/|{O0?
*/ 0.+MlyA
publicint getP(){ G
.NGS%v
return p; ZwM(H[iqL
} \I( g70
;X , A|m$(
/** 8MU+i%hd
* if(p<=0) p=1 4}`z^P<C
* Qhy!:\&1
* @param p 5<YV`T{5Kl
*/ yvv]iRk<
publicvoid setP(int p){ O |!cPB:
if(p <= 0) k..AP<hH
p = 1; f3^Anaa]l
this.p = p; *PM#ngLX}r
} }]<0!q &xB
DHQS7%)f`
/** xa8;"Y~"bg
* 每页记录数量 VYbH:4K@%
*/ ^,}1^?*
publicint getNum(){ zcGmru|k
return num; TophV}@B`
} >cJix
1
5If.[j{
/** cDS\=Bf
* if(num<1) num=1 \(_(pcl
*/ /*P) C'_M
publicvoid setNum(int num){ $O3.ex V
if(num < 1) @CMEmgk~
num = 1; "zj[v1K9-A
this.num = num; T[Lz4;TRk5
} #zRHYZc'T|
f YSH]!
/** [4w*<({*
* 获得总页数 K
@RGvP
*/ DQ<4`wE M
publicint getPageNum(){ xqs ,4bcbY
return(count - 1) / num + 1; ox*1F+Xri
} .J<t]
^hNl6)hR
/** 8yk7d76Y
* 获得本页的开始编号,为 (p-1)*num+1 LI*=T
*/ \#4mPk_"
publicint getStart(){ fqjBor}
return(p - 1) * num + 1; DSQ2|{
} 9TX2h0U?
LAkBf
/** e>6|# d
* @return Returns the results. DL`8qJ'mJs
*/ IdqCk0lVD
publicList<E> getResults(){ 60;_^v
return results; eSQkW
} }ZK%@b>
,~ q:rh+
public void setResults(List<E> results){ }yVx"e)
this.results = results; :_}xN!9LA
}
]VL} eHZ
Z_[ P7P
public String toString(){ 4%2APvLW
StringBuilder buff = new StringBuilder , #=TputM
s_ t/
(); C~egF=w
buff.append("{"); ? X6M8`
buff.append("count:").append(count); "AU.Eh"-1
buff.append(",p:").append(p); nNq<x^@83
buff.append(",nump:").append(num); D=Q.Q
buff.append(",results:").append >$7x]f
A
0v=7
]
(results);
9u^M{6
buff.append("}"); )X?oBNsj
return buff.toString(); Mgr?D
} "\i H/
/jNvHo^B
} ! ui
^3[_4av
3CgID6[Sy