Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 u6|P)8?`
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 3]/w3|y
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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 V&[|%jm&
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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 4WU
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分页支持类: 8q}`4wCD$
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java代码: & Z*&&
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package com.javaeye.common.util; /zM
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import java.util.List; `G6Nk@9.
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publicclass PaginationSupport { {
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publicfinalstaticint PAGESIZE = 30; Dtt[a
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privateint pageSize = PAGESIZE; HS>Z6|uLY
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privateList items; J_<ENs-
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privateint totalCount; j8_WEjG
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privateint[] indexes = newint[0]; &qF
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privateint startIndex = 0; ESL(Mf'
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public PaginationSupport(List items, int c5nl!0XX
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totalCount){ _/ ]4:("
setPageSize(PAGESIZE); ~;9B\fE`
setTotalCount(totalCount); <Pg4>
setItems(items); 1-Sc@WXd
setStartIndex(0); q!t_qX7u
} lL/|{A|-j
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public PaginationSupport(List items, int ^ dM,K
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totalCount, int startIndex){ IJhJfr0)Oo
setPageSize(PAGESIZE); L?23Av0W
setTotalCount(totalCount); LSs!U
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setItems(items); y?zNxk/p
setStartIndex(startIndex); &>XIK8*
} @Q
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public PaginationSupport(List items, int %lF}!
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totalCount, int pageSize, int startIndex){ tl !o;`W
setPageSize(pageSize); NffZttN
setTotalCount(totalCount); {|9x*I
setItems(items); PVC\&YF
setStartIndex(startIndex); 6av]LY K
} :}i
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publicList getItems(){ b%z4u0
return items; "u@)
} {R5Q{]dK3
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publicvoid setItems(List items){ }lvD 5
this.items = items; G];5'd~C;d
} 7Y"CeU-S
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publicint getPageSize(){ :7
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return pageSize; *fQ$s
} c!{v/zOz
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publicvoid setPageSize(int pageSize){ ]>M{Qn*
this.pageSize = pageSize; +]
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} hN=YC\l
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publicint getTotalCount(){ n}Pz:
return totalCount; 7A@]t_83Y
} yj13>"n h
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publicvoid setTotalCount(int totalCount){ :FcYjw
if(totalCount > 0){ @8a1a3_F
this.totalCount = totalCount; ky0Fm
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int count = totalCount / Lf`LFPKb
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pageSize; ZJlmHlAX
if(totalCount % pageSize > 0) ~M7
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count++; ?=}~]A5N
indexes = newint[count]; w
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for(int i = 0; i < count; i++){ %eW[`uyV
indexes = pageSize * A2LqBirkl
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}
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}else{ n#8N{ya5x1
this.totalCount = 0; U>PF#@ C/
} " lar~
} 1#9qP~#]'{
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publicint[] getIndexes(){ _?$P?
return indexes;
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} !|}(tqt
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publicvoid setIndexes(int[] indexes){ 9)N/J\b
this.indexes = indexes; 6P@3UQ)}s
} b~uz\%'3
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publicint getStartIndex(){ jLRUWg
return startIndex; |O =Fz3)
} v,qK=]ty
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publicvoid setStartIndex(int startIndex){ /|v:$iH,C
if(totalCount <= 0) .b'hVOs{
this.startIndex = 0; 46^LPC"x
elseif(startIndex >= totalCount) S^ij %
this.startIndex = indexes ZtG5vdf
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[indexes.length - 1]; =I.
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elseif(startIndex < 0) OY$P8y3MY
this.startIndex = 0; CDOqdBQ
else{ G4DuqN~2m
this.startIndex = indexes sY,q*}SLD
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[startIndex / pageSize]; PgZeDUPP
} wa/
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} svki=GD_(.
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publicint getNextIndex(){ MW&ww14
int nextIndex = getStartIndex() + e}e|??'(\
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pageSize; g_{hB5N](7
if(nextIndex >= totalCount) aI @&x
return getStartIndex(); t<'-?B2g
else ^@V$'Bk
return nextIndex; ,#;%ILF4%
} 96M?tTa
% heX06
publicint getPreviousIndex(){ ~bL^&o(W
int previousIndex = getStartIndex() - +o&&5&HR
5@_c<
pageSize; 5<1,`Bq@
if(previousIndex < 0) zSs5F_
return0; j(JUOief
else D4jf%7X!Lu
return previousIndex; 38(Cj~u=3
}
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} erG@8CG
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抽象业务类 L_$M9G|5n
java代码: hN%
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/** ^ 'jJ~U
* Created on 2005-7-12 b.Wf*I?
*/ GUUVE@Z
package com.javaeye.common.business; &gIDcZ
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import java.io.Serializable; \ dpsyc
import java.util.List; 40VdT|n$$
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import org.hibernate.Criteria; ]F&<{\:_}
import org.hibernate.HibernateException; gm;6v30e
import org.hibernate.Session; S(;3gQ77
import org.hibernate.criterion.DetachedCriteria; `9%Q2Al
import org.hibernate.criterion.Projections; xv!
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import \W73W_P&g
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org.springframework.orm.hibernate3.HibernateCallback; O/;$0`~hY
import !M]_CPh]
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org.springframework.orm.hibernate3.support.HibernateDaoS nx<q]Juv\
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upport; &^-quzlZ
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import com.javaeye.common.util.PaginationSupport; q*Xp"yBTo
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public abstract class AbstractManager extends U4hsbraz
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HibernateDaoSupport { [&mYW.O<
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privateboolean cacheQueries = false; 5x/q\p-{/
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privateString queryCacheRegion; 0q_Ol]<V
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publicvoid setCacheQueries(boolean EFl[u+
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cacheQueries){ #]`ejr:2O
this.cacheQueries = cacheQueries; BS }uv3
} hM*T{|y
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publicvoid setQueryCacheRegion(String sePOW#|
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queryCacheRegion){ 'c#ZW|A
this.queryCacheRegion = w}Q|*!?_
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queryCacheRegion; @nN+F,phx
} h 9V9.'
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publicvoid save(finalObject entity){ ye U4,Ko
getHibernateTemplate().save(entity); IQK__)
} H9)$ #r6i
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publicvoid persist(finalObject entity){
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getHibernateTemplate().save(entity); @:DS/#!
} fT.5@RR7^
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publicvoid update(finalObject entity){ htg+V-,
getHibernateTemplate().update(entity); LyA=(h6
} Py(l+Ik`>
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publicvoid delete(finalObject entity){ X~RET[L2
getHibernateTemplate().delete(entity); IXp P.d
} Vxif0Bx&/d
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publicObject load(finalClass entity, 1 sCF
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finalSerializable id){ $UlA_l29
return getHibernateTemplate().load x@bZ((w
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(entity, id); U[~BW[[@f
} n
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publicObject get(finalClass entity, ]zVe% Wa
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finalSerializable id){ >*A\/Da]j
return getHibernateTemplate().get La}=Ng
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(entity, id); FK!9to>
} NXDV3MH=
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publicList findAll(finalClass entity){ avls[Bq
return getHibernateTemplate().find("from }vO^%Gd
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" + entity.getName()); C<A82u;t%@
} GpF, =:
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publicList findByNamedQuery(finalString &K k+RHM
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namedQuery){ :i*JlKHJd
return getHibernateTemplate +7+
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().findByNamedQuery(namedQuery); [AR$Sw60
} Hkx FDU-K
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publicList findByNamedQuery(finalString query, /S9Mu
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finalObject parameter){ A"eT@
return getHibernateTemplate fE)+9!
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().findByNamedQuery(query, parameter); fx.FHhVu
} Y_PCL9G{p
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publicList findByNamedQuery(finalString query, CT4R/wzY7
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finalObject[] parameters){ >C_! }~
return getHibernateTemplate Q}]:lmqH
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().findByNamedQuery(query, parameters); ) !ZA.sx
} R|!4Y`
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publicList find(finalString query){ c<JJuG
return getHibernateTemplate().find SVXey?A;CJ
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(query); F>A-+]X3o
} vWfC!k-)b
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publicList find(finalString query, finalObject Q*$x!q
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parameter){ X?rJO~5
return getHibernateTemplate().find >!? f6
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(query, parameter); 9FK:lFGD
} mMT7`r;l
9FV#@uA}D
public PaginationSupport findPageByCriteria #D//oL"u]
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(final DetachedCriteria detachedCriteria){ o?{VGJH<v
return findPageByCriteria r(vk2Qy
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); O";r\Z
} ?\\
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public PaginationSupport findPageByCriteria tGmyTBgx
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(final DetachedCriteria detachedCriteria, finalint W,Dr2$V
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startIndex){ ~,':PUkiV
return findPageByCriteria &B3\;|\
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(detachedCriteria, PaginationSupport.PAGESIZE, 7\{<AM?*
<#|3z8N2
startIndex); by6E
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} d:sUh
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public PaginationSupport findPageByCriteria 9lTA/-
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(final DetachedCriteria detachedCriteria, finalint (2qo9j"j/Y
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pageSize, 0TA/ExJ-LT
finalint startIndex){ >+oQxml6nI
return(PaginationSupport) ?wwY8e?S
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getHibernateTemplate().execute(new HibernateCallback(){ u> >t"w
publicObject doInHibernate $8it&/JP,
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(Session session)throws HibernateException { d\Dxmb]o
Criteria criteria = 2?-}(F;Z
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detachedCriteria.getExecutableCriteria(session); i@B5B2
int totalCount = a+]=3o
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((Integer) criteria.setProjection(Projections.rowCount pm )A*][s
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()).uniqueResult()).intValue(); p3^7Hr
criteria.setProjection RNvtgZ}k{X
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(null); kt;X|`V{5z
List items = wRie{Vk
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criteria.setFirstResult(startIndex).setMaxResults 9pjk3a
_TX.}167;-
(pageSize).list(); |y'q`cY
PaginationSupport ps = j<L!ONvJ1
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new PaginationSupport(items, totalCount, pageSize, &x=<>~Ag3
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startIndex); 5gJQr%pS
return ps; SH}O?d\Q:
} yobi$mnsy!
}, true); HmX(=Y
} ;UPw;'
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public List findAllByCriteria(final * rs_k/2(
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DetachedCriteria detachedCriteria){ 80+"
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return(List) getHibernateTemplate i!,>3
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().execute(new HibernateCallback(){ ! B)Em
publicObject doInHibernate "sHD8TUX
, H[o.r=
(Session session)throws HibernateException { VJ1`&
Criteria criteria = ruE.0V I@
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detachedCriteria.getExecutableCriteria(session); s@3!G+ -}
return criteria.list(); R6AZIN:
} sk],_ l<
}, true); C2`END;
} 3d,|26I 7f
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public int getCountByCriteria(final #4"\\
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DetachedCriteria detachedCriteria){ ~KX!i
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Integer count = (Integer) {=R=\Y?r&
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getHibernateTemplate().execute(new HibernateCallback(){ e| kYu[^
publicObject doInHibernate }D|"$*
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(Session session)throws HibernateException { /Hd\VI
Criteria criteria = O~xc>
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detachedCriteria.getExecutableCriteria(session); % l5J
return * |,V$
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criteria.setProjection(Projections.rowCount 4QDF%#~q^
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()).uniqueResult(); 'vCFT(C-
} +$<m ;@mZ
}, true); h<uRlTk
return count.intValue(); ]AfeaU'>
} #~ >0Dr
} ?. ~@ lE
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用户在web层构造查询条件detachedCriteria,和可选的 s=KA(4p
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 NVOY,g=3X
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PaginationSupport的实例ps。 (F#Qu nze
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ps.getItems()得到已分页好的结果集 Z?^AX&F
ps.getIndexes()得到分页索引的数组 cZHlW|$R
ps.getTotalCount()得到总结果数 >B3_P4pW9
ps.getStartIndex()当前分页索引 `[`eg<xj
ps.getNextIndex()下一页索引 b9"Q.*c<Z^
ps.getPreviousIndex()上一页索引 ?N`W,
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 :@n e29,}
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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 L-$GQGk{
/dtFB5Z"w
一下代码重构了。 a}=)b#T`
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我把原本我的做法也提供出来供大家讨论吧: eLl;M4d
RX#:27:
首先,为了实现分页查询,我封装了一个Page类: H'2pmwk
java代码: ,@GI3bl
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/*Created on 2005-4-14*/ LnM+,cBz
package org.flyware.util.page; 6LUB3;g7
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/** mGoUF$9 k
* @author Joa c!6.D
* 0 5 `x$f
*/ ?L7z\b"_~
publicclass Page { W${0#qq
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/** imply if the page has previous page */ >a]{q^0
privateboolean hasPrePage; ve'h z{W
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/** imply if the page has next page */ *y u|]T
privateboolean hasNextPage; 2}hEBw68
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/** the number of every page */ 91[(K'=&
privateint everyPage; k`xPf\^tf
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/** the total page number */ _PQQ&e)E
privateint totalPage; Y+lZT4w
4fQ<A <2/
/** the number of current page */ >~2oQ[n
privateint currentPage; ,uK
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/** the begin index of the records by the current )g+~"&Gcx
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query */ "){"{~
privateint beginIndex; A"d=,?yE
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/** The default constructor */ `BF +)fs
public Page(){ ~xkcQ{
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} 8FU8E2zo
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/** construct the page by everyPage <Zn]L:
* @param everyPage b-\ 1D;]
* */ 2w+w'Ag_R
public Page(int everyPage){ G[ @RZ~o4
this.everyPage = everyPage; <V>]-bl/
} h b_"E, `F
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/** The whole constructor */ Y'mtMLfMc
public Page(boolean hasPrePage, boolean hasNextPage, =g
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int everyPage, int totalPage, J>TNyVaoQ
int currentPage, int beginIndex){ #;z;8q
this.hasPrePage = hasPrePage; ACc tyGd
this.hasNextPage = hasNextPage; eD4X:^@
this.everyPage = everyPage; Uyj6Ij_Pj)
this.totalPage = totalPage; Xq@Bzya
this.currentPage = currentPage; <Y:{>=
this.beginIndex = beginIndex; Nu/wjx$b
} B/0Xqyu
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/** #p*D.We
* @return +DU^"q=
* Returns the beginIndex. [0qe ?aI
*/ e];lDa#4-Y
publicint getBeginIndex(){ x+EkL3{
return beginIndex; Je5}Z.3m
} u0zF::
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/** lE'3U qK
* @param beginIndex ,)@njC?J
* The beginIndex to set. JuQwZ]3ed
*/ X|y(B%:
publicvoid setBeginIndex(int beginIndex){ vJ9I z
this.beginIndex = beginIndex; {bHUZen
} JlR$"GU
~@ =(#tO.
/** xsu9DzPf&{
* @return SO4?3wg7
* Returns the currentPage. z?dd5.k
*/ `i`+yh>pc#
publicint getCurrentPage(){ FkE)~g
return currentPage; Pm&h v*D
} :e1kpQ
ORuC("
/** %|j`z?i|
* @param currentPage y^Uh<L0M
* The currentPage to set. R!f<6l8#W
*/ ;`Nh@*_
publicvoid setCurrentPage(int currentPage){ _Ne fzZWUJ
this.currentPage = currentPage; v;soJlxF~
} cX7 O*5C
}D># AFs6#
/** VKV
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* @return 1r$*8|p
* Returns the everyPage. vMd3#@
*/ o1`\*]A7J
publicint getEveryPage(){ 7UIf
return everyPage; aD]!
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} NNt
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/** 0civXZgj
* @param everyPage *4/FN TC
* The everyPage to set. =PU($
*/ is
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publicvoid setEveryPage(int everyPage){ ]Hp>~Zvbb
this.everyPage = everyPage; KpA1Ac)T
} pHT]2e#
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/** .G.WPVE
* @return CYRZ2Yrk?"
* Returns the hasNextPage. /~MH]Gh
*/ t0+i]lr
publicboolean getHasNextPage(){ U%q-#^A
return hasNextPage; F+"_]
} j$K*R."
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/**
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* @param hasNextPage wBcoh~
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* The hasNextPage to set. !_vxbfZO
*/ SE'!j]6jI
publicvoid setHasNextPage(boolean hasNextPage){ P q$0ih
this.hasNextPage = hasNextPage; ;$WHTO(
} Y{D%v
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/** +$|fUn{
* @return W:,Wex^9n
* Returns the hasPrePage. H4s~=iB
*/ gVrQAcJj
publicboolean getHasPrePage(){ ')U~a
return hasPrePage; ki?h7
} !!A0K"h
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/** V(_1q
* @param hasPrePage B*N1)J\5
* The hasPrePage to set. y(o)}m*0
*/ V:$+$"|
publicvoid setHasPrePage(boolean hasPrePage){ RN[I%^$"
this.hasPrePage = hasPrePage; H T|DT
} Keozn*fzI
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/** CJ*
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* @return Returns the totalPage. _Z23lF9
* )\|+G5#`
*/ <%HRs>4
publicint getTotalPage(){ [ n7>g
return totalPage; #,%7tXOLR
} R|C2O[r}
l-Z( ]
/** fC[za,PXaE
* @param totalPage EHk\Q\
* The totalPage to set. gxN>q4z
*/ L-T,[;bl
publicvoid setTotalPage(int totalPage){ @eJCr)#}
this.totalPage = totalPage; N7?B"p/
} H5T_i$W
x;17}KV
} q0iJy@?A
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上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 ;f=m+QXU
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个PageUtil,负责对Page对象进行构造: j{@6y
java代码: Mf1(4F
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/*Created on 2005-4-14*/ 3 r&
package org.flyware.util.page; O$<>v\NC?
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import org.apache.commons.logging.Log; !cwZ*eM
import org.apache.commons.logging.LogFactory; Q?#I{l)V(
2;8m0+tl
/** qhEv6Yxfw6
* @author Joa FQ]/c#J
* T$I_nxh[)L
*/ Mfj82rHg
publicclass PageUtil { -L1785pB85
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privatestaticfinal Log logger = LogFactory.getLog
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(PageUtil.class); ilA45@
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/** mQj=-\p
* Use the origin page to create a new page {KG 6#/%;
* @param page
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* @param totalRecords FACw;/rW
* @return 8]ZzO(=@{
*/ 1~5DIU^
publicstatic Page createPage(Page page, int qN $t_
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totalRecords){ `*C=R
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return createPage(page.getEveryPage(), +$h
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page.getCurrentPage(), totalRecords); R4m{D
} ={qcDgn~C
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/** [3Pp
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* the basic page utils not including exception [nTI\17iA
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handler o~Se[p
* @param everyPage
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* @param currentPage Ld4U
* @param totalRecords ZK5nN9`
* @return page S+ kq1R
*/ 1E+12{~m"i
publicstatic Page createPage(int everyPage, int g!'R}y
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currentPage, int totalRecords){ N3%X>*'
everyPage = getEveryPage(everyPage); VdLoi\-/L
currentPage = getCurrentPage(currentPage); H@Dpht>[
int beginIndex = getBeginIndex(everyPage, M]x>u@JH
x:|Y)Dn\
currentPage); ~}Xus?e
int totalPage = getTotalPage(everyPage, A,}M ^$@
WYP ;s7_
totalRecords); ;<[X\;|'
boolean hasNextPage = hasNextPage(currentPage, +yGQt3U
:xd;=;q5
totalPage); . %RM8
boolean hasPrePage = hasPrePage(currentPage); b)LT[>f
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returnnew Page(hasPrePage, hasNextPage, p/.8})c1r
everyPage, totalPage, c{z$^)A/
currentPage, J:xGEa t
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beginIndex); al2t\Iq90
} MdHm%Vx
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privatestaticint getEveryPage(int everyPage){ 22gh!F%)
return everyPage == 0 ? 10 : everyPage; j[>cv;h
;
} fab'\|Y
,X4e?$7g
privatestaticint getCurrentPage(int currentPage){ NAbVH{*\U
return currentPage == 0 ? 1 : currentPage; dbI>\khI
} )t6]F6!_
,YYEn^:>
privatestaticint getBeginIndex(int everyPage, int w5@5"M
RK3 yq$
currentPage){ $l7^-SK`E
return(currentPage - 1) * everyPage; 79\wjR!T
} _P>YG<*"kQ
.E4*>@M5
privatestaticint getTotalPage(int everyPage, int E5k)~P`|
{o=?@ $6C
totalRecords){ NGx3f3 9
int totalPage = 0; 6TtB3;5
*rxr:y#Ve
if(totalRecords % everyPage == 0)
5)[~
T2j!
totalPage = totalRecords / everyPage; f6Qr0Op
else /jbAf ]"F;
totalPage = totalRecords / everyPage + 1 ; ?t#wK}d.
<`H0i*|Ued
return totalPage; ll:UIxx
} e+
xQ\LH
Sj9fq*
privatestaticboolean hasPrePage(int currentPage){ !jCgTo
y
return currentPage == 1 ? false : true; K1&
QAXyP
} 1!#85SMx
%y1!'R:ZW
privatestaticboolean hasNextPage(int currentPage, NvR{S /Z
(O.%Xbx3
int totalPage){ &!!*xv-z
return currentPage == totalPage || totalPage == 5> k:PKHL
7T~M`$h
0 ? false : true; [$N_YcN?
} }X(&QZ7i`
+mQ5\14#
u-_r2U
} Hbm 4oYN
PwY/VGT
'ofj1%c
0-2|(9
Kc
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上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 ui8 Q2{z
Y\|#Lu>B
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 S-Uod y
=ily=j"hK
做法如下: lqzt[z gN
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 D3pz69W
b 2gng}
的信息,和一个结果集List: h Yu6PWK
java代码: Xn7G2Yp
JA^o/%a^
^X#y'odtbS
/*Created on 2005-6-13*/ RObnu*
package com.adt.bo; |s8N
M`MxdwR
import java.util.List; uuzV,q
.*O*@)}Ud
import org.flyware.util.page.Page; *~rj!N?;
Q
eeV<
/** mScv7S~/s
* @author Joa UaT%tv>}8#
*/ .)Tj}Im2p
publicclass Result { q"2QNF'
v.0qE}'
|
private Page page; j=\h|^gA
WI8}_){ d
private List content; 1? >P3C
SzULy
>e
/** ^-o{3Q(w
* The default constructor /:dLqyQ_V
*/ %mI0*YRma
public Result(){ 'yo@5*x7
super(); {U4!sJSl1
} /dnwN7Gf
b)wcGBS
/** 2u{~35
* The constructor using fields i'~-\F!
* xR7ZqTcw
* @param page ]5%0EE64
* @param content sdp&D@
*/ #3uv^m LGa
public Result(Page page, List content){ (vXr2Z<l
this.page = page; WBe0^=x
this.content = content; 4GYi'
} lExQp2E
0<M-asI?
/** ,'L>:pF3
* @return Returns the content. PyeNu3Il4
*/ 6[bopin
publicList getContent(){ G gO5=|
return content; JK,MK|
} #w$Y1bjn
^FCXcn9
/** :X2_#qW#C
* @return Returns the page. =SDex.ZK]
*/ 7h'
C"rH
public Page getPage(){ qF)J#$4;6
return page; u?').c4
} awLvLkQb{
"N4^ ^~s
/** ?hoOSur+
* @param content r>mBe;[TX
* The content to set. u6iW1,#
*/ _3IT3mb2n
public void setContent(List content){ Vax g
this.content = content; !-I,Dh-A
} `sjY#Ua<
# :+Nr
/** GwWK'F'2
* @param page kc'$4 J4Tw
* The page to set. iTxWXij
*/ _"DC)
publicvoid setPage(Page page){ r6<;bO(
this.page = page; _[:6.oNjIe
} g)Z8WH$;H3
} D%>Bj>xQD
6)[moR{N1
y<`5
d3%qYL_+a
Y,L`WeQY.
2. 编写业务逻辑接口,并实现它(UserManager, RB>=#03
5Ds[?
UserManagerImpl) [@$ SLl^Y
java代码: f \&X$g
pyEQb#
n,T
&n
/*Created on 2005-7-15*/ ]3r}>/2(
package com.adt.service; Upz)iOqLi
:UwBs
import net.sf.hibernate.HibernateException; 44CZl{pt
U1\EwBK8*T
import org.flyware.util.page.Page; 3Tr,waV
.G/Rh92
import com.adt.bo.Result; ~ !uX"F8Xl
`$a!CJu,
/** <H64L*,5'7
* @author Joa :8S;34Y;
*/ &X4anH>O
publicinterface UserManager { HwU9y
E|pT6
public Result listUser(Page page)throws H3wJ5-q(
xd?=#d
HibernateException; >Eh U{@Y
s.M39W?
} O:BdZ5
b
qI'pjTMDY
(Y py}
n"iS[uj,
txEN7!
java代码: Z% +$<J
Y e0,0Fpw
wd:Yy
/*Created on 2005-7-15*/
9qX$
package com.adt.service.impl; !ooi.Oz*Tu
P"c@V,.
import java.util.List; `IN!#b+Eo
<4{m99
import net.sf.hibernate.HibernateException; 2V~E
<K-
UfW=/T
import org.flyware.util.page.Page; /gAT@Vx
import org.flyware.util.page.PageUtil; V|Bwle
eKLvBa-{@
import com.adt.bo.Result; }6Pbjm *
import com.adt.dao.UserDAO; %/dOV[/
import com.adt.exception.ObjectNotFoundException; Whd >
import com.adt.service.UserManager; X5owAc6
r8"2C#
/** S1|5+PPs
* @author Joa $f@YQN=
*/ |s3;`Nxu7
publicclass UserManagerImpl implements UserManager { "#)|WVa=BM
/xX7:U b
private UserDAO userDAO; _2KIe(,;
,ye}p1M
/** 8T+9
fh]I
* @param userDAO The userDAO to set. j_C"O,WS
*/ H&-3`<
publicvoid setUserDAO(UserDAO userDAO){ ByY^d#oE
this.userDAO = userDAO; ^%!{qAp}Z
} l]G
iz&
628iN%[-
/* (non-Javadoc) &JX<)JEB=<
* @see com.adt.service.UserManager#listUser A%#M#hD/
@ ]u@e4T
(org.flyware.util.page.Page) )q x;/=D
*/ G]h_z|$K
public Result listUser(Page page)throws |GMo"[
^cZ< .d2
HibernateException, ObjectNotFoundException { ##mZ97>$
int totalRecords = userDAO.getUserCount(); v4e4,Nt
if(totalRecords == 0) -1Tr!I:1
throw new ObjectNotFoundException AL":j6!OQ
A=kOSq 4Q
("userNotExist"); a!R*O3
page = PageUtil.createPage(page, totalRecords); $WIE`P%
List users = userDAO.getUserByPage(page); (IV\sY
returnnew Result(page, users); 3JC uM_y
} /mwUDf 6x
J4+WF#xI2
} iw#~xel<ez
{.Qv1oOa
aV5M}:D
0SvPr[ >
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其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 RB4n>&Y
k86TlQRh
询,接下来编写UserDAO的代码: F]M-r{
3. UserDAO 和 UserDAOImpl: LqYyIbsvf
java代码: Tdh(J",d
*=i&n>
<ll?rPio"
/*Created on 2005-7-15*/ UvGxA[~2+
package com.adt.dao; D>k(#vYKB
)l9KDObis
import java.util.List; 1j<uFhi>
G,>YzjMY`
import org.flyware.util.page.Page; M|c_P)7ym
A6[FH\f
import net.sf.hibernate.HibernateException; $'KQP8M+
e6MBy\*n
/** ;8oe-xS\+
* @author Joa mrr]{K
*/ ?98!2:'{9
publicinterface UserDAO extends BaseDAO { ='jT
5Mg
j^=Eu r/
publicList getUserByName(String name)throws ]AQ}_dRi=
WowT!0$
HibernateException; $y6 <2w%b
2.WI".&y=
publicint getUserCount()throws HibernateException; L ~'98C
w71YA#cg
publicList getUserByPage(Page page)throws @%fTdneH
bN-!&Td
HibernateException; WzstO}?P(
inh:b .,B
} XB7*S*"!
46]BRL2 G
YyYZD{^
G@/iK/>5|`
\dCGu~bT
java代码: d4ecF%R
w:lj4Z_
wH8J?j"5>
/*Created on 2005-7-15*/ :!MEBqcU
package com.adt.dao.impl; {U2AAQSa
7f+@6jqD\)
import java.util.List; tTBDb
e_e\Ie/pDc
import org.flyware.util.page.Page; f2[R2sto@
q{`1[R
import net.sf.hibernate.HibernateException; M?YNK]
import net.sf.hibernate.Query; y5F+~z}{
:+6W%B
import com.adt.dao.UserDAO; q83^?0WD
`E1G9BbU
/** Mv%Qze,\V^
* @author Joa zc8^#D2y&
*/ sJx_X8
public class UserDAOImpl extends BaseDAOHibernateImpl fD@d.8nXd
zHA::6OgPN
implements UserDAO { R& t*x
Hrpz4E%\Aw
/* (non-Javadoc) rX)&U4#[m
* @see com.adt.dao.UserDAO#getUserByName v4hrS\M
b9rQQS
(java.lang.String) &V1d"";SZ
*/ P!Fykg
publicList getUserByName(String name)throws }Q4Vy
?|kbIZP(
HibernateException { x?o#}:S
String querySentence = "FROM user in class RAl/p9\A+
Eo2`Vr9g
com.adt.po.User WHERE user.name=:name"; iXy1{=BDv
Query query = getSession().createQuery FbroI>" e
_|US`,kfc
(querySentence); "<+~uz
query.setParameter("name", name); (Ff}Y.4
return query.list(); !O%!A<3
} EtzSaB*|
Xgd-^
/* (non-Javadoc) -_n Qn
* @see com.adt.dao.UserDAO#getUserCount() VIdKe&,
*/ Wz.iDRFl
publicint getUserCount()throws HibernateException { p#jAEY p
int count = 0; iS,l
String querySentence = "SELECT count(*) FROM D(ItNMcKu
rmzzbLTu
user in class com.adt.po.User"; H2%Qu<Kg2
Query query = getSession().createQuery (9RfsV4^
7:olStK
(querySentence); ^P@:CBO
count = ((Integer)query.iterate().next 'UhHcMh:
m[xl)/e
()).intValue(); jbipNgxkr
return count; vN^.MR+<
} pk9Ics;y
Ez~5ax7x
/* (non-Javadoc) g>h/|bw4
* @see com.adt.dao.UserDAO#getUserByPage 2|^@=.4\
]O@iT= *3
(org.flyware.util.page.Page) te(H6c#0
*/ iV/I909*''
publicList getUserByPage(Page page)throws JD#q6&|
=gI41Y]
HibernateException { d~qQ_2M[G
String querySentence = "FROM user in class 9no<;1+j,
=_ pSfKR;
com.adt.po.User"; _cQ
'3@
Query query = getSession().createQuery U4=l`{5on
f2x!cL|Kx?
(querySentence); 0]bt}rh
query.setFirstResult(page.getBeginIndex()) cZ_)'0
.setMaxResults(page.getEveryPage()); 'wEQvCS
return query.list(); <z\SKR[
} Oe;#q
't`h?VvL
} y/\b0&
KV$&qM.
QO}~"lMj
SM8N*WdiU
<b
H*f w
至此,一个完整的分页程序完成。前台的只需要调用 ,Tr&`2w
3`yO&upk
userManager.listUser(page)即可得到一个Page对象和结果集对象 nSyLt6zn\
+]cf/_8+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 YFXF
3[u-
LYW
webwork,甚至可以直接在配置文件中指定。 Fge%6hu
3eE=>E4,
下面给出一个webwork调用示例: DWOf\[
java代码: ;Va(l$zD
'r 7[9[
~'lT8 n_
/*Created on 2005-6-17*/ iSO xQ
package com.adt.action.user; aI&~aezmN
7he,(V
import java.util.List; /al56n
FTCIfW
import org.apache.commons.logging.Log; :Q DkaA
import org.apache.commons.logging.LogFactory; bUS:c
2"
import org.flyware.util.page.Page; Oq~{HJ{
9SsVJ<9,R
import com.adt.bo.Result; d[9{&YnH !
import com.adt.service.UserService; ;/$pxD
import com.opensymphony.xwork.Action; {.$7g8]I
ij0I!ilG4
/** g7]S
* @author Joa Pv5S k8
*/ (.P}>$M9
publicclass ListUser implementsAction{ `15}jTi
I>FL&E@K
privatestaticfinal Log logger = LogFactory.getLog [<f2h-V$
*fc8M(]&d
(ListUser.class); :4V5p
=v-
jdG2u
p
private UserService userService; HSNj
c
qCNk
private Page page; ):PN0.H8
b\ED<'
privateList users; :bct+J}l~
"qq$i35x
/* K>+ v" x
* (non-Javadoc) uuEvH<1
* gGvL6Fu
* @see com.opensymphony.xwork.Action#execute() C`[2B0
*/ C{/U;Ie-b
publicString execute()throwsException{ K*j
OrQf`
Result result = userService.listUser(page); o4p5`jOG@
page = result.getPage(); 5go)D+6s
users = result.getContent(); ;xiN<f4B
return SUCCESS; )8oyo~4?
} RL4|!HzR
ra*|HcLD
/** 6<W^T9}v@/
* @return Returns the page. T3oFgzoO
*/ e=VSO!(rY
public Page getPage(){ <~uzHg%Y
return page; sC\?{B0r
} WDghlC6g!l
dYISjk@
/** J'WzEgCnU
* @return Returns the users. c\ZI
5&4jT
*/ X[?fU&
publicList getUsers(){ }Y7P2W+4?
return users; _qPKdGoM
} ]zj#X\
7fypUQ:y
/** IrYj#,xJ
* @param page )8^E{w^D}
* The page to set. T^^7@\vDI
*/ (enr{1
publicvoid setPage(Page page){
bMc[0
this.page = page; Z#u{th
} q'S[TFMNE
+Iuu8t
/** A v>v\ :.>
* @param users %G(VYCeK
* The users to set. :7X4VHw/
*/ ;L fn&2G
publicvoid setUsers(List users){ 392(N(
this.users = users; SVVE b6&
} ILDO/>n
[gUD +
/** r(wf>w3
* @param userService JG^GEJ
* The userService to set. \1<aBgKi
*/ <[ dt2)%L>
publicvoid setUserService(UserService userService){ " TCJT390
this.userService = userService; tOVTHx3E]
} nL^7t7mp
} 2|?U%YrHWs
N}/V2K]Q
>.UEs8QV
DW,ERQ^
=k d-rIBc
上面的代码似乎看不出什么地方设置了page的相关初值,事实上, 56YqYu.
='.b/]! _
可以通过配置文件来进行配置,例如,我想每页显示10条记录,那 j{FRD8]V
F}mt
*UcMG
么只需要: GTbV5{Ss
java代码: :-59~8&
yD\Kn{
&^&0,g?To
<?xml version="1.0"?> j8Q_s/n
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork Heqr1btK
PSAEW.L
1.0//EN" "http://www.opensymphony.com/xwork/xwork- ;C =d(
pY
x Y$x=)
1.0.dtd"> 5hEA/G
MA9E??p3\
<xwork> m==DBh
z+oy#p6+F.
<package name="user" extends="webwork- hB<(~L?A]
!_+FuF"@
interceptors"> U7U&^s6`
I3.JAoB>!
<!-- The default interceptor stack name XjzGtZ#6
g3'dkS!
--> IN6L2/Q
<default-interceptor-ref hyPS 6Y'1
^3vI
NF
name="myDefaultWebStack"/> bhDqRM
21<Sfsc$
<action name="listUser" $[HCetaqV
yo_zc<
class="com.adt.action.user.ListUser"> J s33S)
<param A+Un(tU2(
g}6M+QNj
name="page.everyPage">10</param> 66B,Krz1n
<result \COoU("
ci?\W6
name="success">/user/user_list.jsp</result> (i{ZxWW&
</action> WUYU\J&q3
!j #8zN
</package> zO9WqP_`iR
c<q33dZ!*
</xwork> D)4#AI
&<&eKq
[KGj70|~
3`3my=
|jH Yf42Q
F{ 4k2Izr
这样就可以通过配置文件和OGNL的共同作用来对page对象设置初值 Z
*tHZ7b
+Y+fM
了。并可以通过随意修改配置文件来修改每页需要显示的记录数。 0%rE*h9+
U7zd7O
注:上面的<param>的配置,还需要webwork和Spring整合的配合。
`|nJAW3
2b\h@VJt
(:H4
M?sTz@tqq
@~=d4Wj6
我写的一个用于分页的类,用了泛型了,hoho RK&RMN8@
LCIe1P2
java代码: Tsu\4
cL]
b
H5lLcdf
B|^=2 >8s
package com.intokr.util; ] -C*d$z
Ea" -n9
import java.util.List; R Ee~\n+P^
H2g#'SK@
/** {P?p*2J'
* 用于分页的类<br> 6ypHH
2X
* 可以用于传递查询的结果也可以用于传送查询的参数<br> tG"EbWi
* ;&w_.j*Is
* @version 0.01 .db:mSrL
* @author cheng 2S@Cj{R(
*/ LChwHkRHJI
public class Paginator<E> { P
2x.rukT|
privateint count = 0; // 总记录数 xOxyz6B\
privateint p = 1; // 页编号 DM)Re~*
privateint num = 20; // 每页的记录数 g_Y$5ft`
privateList<E> results = null; // 结果 Q'e[(^8
gi_f8RP=2a
/** N-<,wUxf
* 结果总数 S}/ZHo
*/ ~2Mcw`<
publicint getCount(){ ?ODBW/{[G
return count; R6GlQ G
} bV)h\:oC
"5sUE!)f
publicvoid setCount(int count){ 44B9JA7u
this.count = count; [--] ?Dr
} ZD?LsD 3
zU|'IW&
/** {oo(HD;5
* 本结果所在的页码,从1开始 iqd7
* ,0,&
L
* @return Returns the pageNo. ?[5_/0L,=
*/ 1OK~*=/4
publicint getP(){ XS0NjZW
return p; Q;z'"P
} >O1u![9K|w
9Pm|a~[m
/** O~Dm|hP
* if(p<=0) p=1 (iO/@iw
* 2+YM .Zl
* @param p YMwL(m1
*/ |' kC9H[>
publicvoid setP(int p){ NQbgk+&wD
if(p <= 0)
Es:oXA
p = 1; `GooSX
this.p = p; h&Q-QU
} srU*1jD)
'Hq#9?<2M
/** tF!C']
* 每页记录数量 }"^d<dvuz
*/ ~X) 1!Sr
publicint getNum(){ K;g6V!U
return num; /-ewCCzZV
} Pz' Zn
F
n*+uk
/** <oTNo>U/k
* if(num<1) num=1 \T`iq[+6
*/ Ve\!:,(Y_
publicvoid setNum(int num){ v`"BXSmp{
if(num < 1) u9}LvQh_6,
num = 1; !?{%9
this.num = num; C #@5:$
} kgF x
/T<,vR
/** hQJ-
~
* 获得总页数 sGbk4g
*/ ?trqe/
publicint getPageNum(){ 2C&l\16
return(count - 1) / num + 1; MOP#to)k&
} Oufdi3h
G9c2kX.Bf
/** +,0 :L :a
* 获得本页的开始编号,为 (p-1)*num+1 .t%`"C
*/ ^ G>/;mZ
publicint getStart(){ 3)~z~p7
return(p - 1) * num + 1; 3%V VG~[
} 9D& 22hL4
{F$MZ2 E
/** Si[xyG6=
* @return Returns the results. uI&<H T?
*/ hjoxx
F\_
publicList<E> getResults(){
gm@%[
return results; 8:Jc2K
} 'miY"L:| O
]0@
J)Z09
public void setResults(List<E> results){ rWzO>v
this.results = results; X$$b :q
} pH!8vnoA
7`t[|o
public String toString(){ O(44Dy@2
StringBuilder buff = new StringBuilder \kksZ4,
.:+&2#b
(); T#G
(&0J5
buff.append("{"); y{uN+QS
buff.append("count:").append(count); h*zHmkFR
buff.append(",p:").append(p); f5|Ew&1EP
buff.append(",nump:").append(num); 1ml{oqNj
buff.append(",results:").append vWpkU<&3|
4>8'.8S
(results); iN@+,]Yjl
buff.append("}"); JlN<w
return buff.toString(); P<gr=&
} w^aI1M50
UkXf)
} /M8&`
x4bj?=+
6`hHx=L