Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 F-F1^$]k
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 7[mP@ {
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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 WFzM s
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自于Quake Wang的javaeye-core包的相应类,然后又做了很多修改 lWH#/5`h
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分页支持类: #C'E'g0
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java代码: K2\)9
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package com.javaeye.common.util; +6}CNC9Mp
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import java.util.List; H}lz_#Z
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publicclass PaginationSupport { HO_(it \
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publicfinalstaticint PAGESIZE = 30; B'mUDW8\D
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privateint pageSize = PAGESIZE; vC^{,?@
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privateList items; Q1{9>NI
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privateint totalCount; b#"&]s-
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privateint[] indexes = newint[0]; rC]k'p2x
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privateint startIndex = 0; *0?@/2&
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public PaginationSupport(List items, int FC~%G&K/q^
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totalCount){ *-(o. !#1
setPageSize(PAGESIZE); !! )W`
setTotalCount(totalCount); FzP1b_i
setItems(items);
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setStartIndex(0); /u_9uJ"-K(
} @$t\yBSK
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public PaginationSupport(List items, int x]`@%8Sm
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totalCount, int startIndex){ 4e;$+!dlV
setPageSize(PAGESIZE); ^nNpT!o
setTotalCount(totalCount); <3/_'/C
setItems(items); Lz p}<B
setStartIndex(startIndex); <2]D3,.g.
} uFb
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public PaginationSupport(List items, int 3:8p="$F
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totalCount, int pageSize, int startIndex){ 'ey62-^r6
setPageSize(pageSize); ~iQBgd@D^
setTotalCount(totalCount); !4FOX>|L@
setItems(items); "vQ%`
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setStartIndex(startIndex); 2"6qg>]-t
} olA+B
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publicList getItems(){ Ewq@>$_!
return items; $$W2{vr7+
} A+frKoi
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publicvoid setItems(List items){ ,6pGKCUU:y
this.items = items; CY{!BV'
} O^ui+44wp
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publicint getPageSize(){ Rg\4#9S JF
return pageSize; Ycq )$7p
} HwZl"!;Mry
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publicvoid setPageSize(int pageSize){ /V`SJ"
this.pageSize = pageSize; HS
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} 6&0G'PMf
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publicint getTotalCount(){ Jc}6kFgO6
return totalCount; aPK:k$.
} K|$c#X
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publicvoid setTotalCount(int totalCount){ vr{|ubG]d
if(totalCount > 0){ /\uopa
this.totalCount = totalCount; ^Go,HiB
int count = totalCount / r\F2X J^
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pageSize; 7CSz
if(totalCount % pageSize > 0) gPc1oc(
count++; rPyjr(I"_
indexes = newint[count]; ~o|sm a5.
for(int i = 0; i < count; i++){ DTM(SN8R+n
indexes = pageSize * TQNdBq5I6
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i; <nG}]Smd7
} OHj>ufwVq
}else{ wbcip8<t
this.totalCount = 0; p-)@#hE
} u0sN[<
} -3~S{)
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publicint[] getIndexes(){ ;<''oY
return indexes; ?I?~BWu
} :p@jslD
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publicvoid setIndexes(int[] indexes){ $joGda
this.indexes = indexes; +v5f-CBu
} ?E
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publicint getStartIndex(){ @ NL<v-t
return startIndex; ss }-YnG
} 0 V]MAuD($
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publicvoid setStartIndex(int startIndex){ ht L1aQ.
if(totalCount <= 0) &Ejhw3Nw
this.startIndex = 0; @&&}J
elseif(startIndex >= totalCount) _Li.}g@Bd
this.startIndex = indexes fQU_:[
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[indexes.length - 1]; xg^%8Ls^
elseif(startIndex < 0) gg^iYTpt
this.startIndex = 0; X(Mpg[,N"
else{ ')yYpWO
this.startIndex = indexes Q(aNa!
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[startIndex / pageSize]; a3w6&e`
} ):Z#!O<
} `uk=2k}&m
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publicint getNextIndex(){ Yy]TU} PY
int nextIndex = getStartIndex() + R2{]R&wtn0
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pageSize; /AOGn?Z3
if(nextIndex >= totalCount)
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return getStartIndex(); 4VeT]`C^h
else b&4JHyleF
return nextIndex; B=%%3V)2
} 6bjZW ~
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publicint getPreviousIndex(){ WoB'B|%
int previousIndex = getStartIndex() - na9YlJ\
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pageSize; 5Uy*^C7M^
if(previousIndex < 0) ;~$Q;m1
return0; <P0 P*>M
else g{sp<w0
return previousIndex; pp1Kor
} I8T*_u^_
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} g$"x,:2x{
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抽象业务类 1R*;U8?
java代码: kCz2uG)l
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/** {g1R?W\LZ
* Created on 2005-7-12 cL.>e=x$
*/ Bfdfw+
package com.javaeye.common.business; G.@K#a9
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import java.io.Serializable; Gl3g.`X{$@
import java.util.List; !blGc$kC
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import org.hibernate.Criteria; i,Z-UA|f=T
import org.hibernate.HibernateException; -Q
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import org.hibernate.Session; <?L5bhq
import org.hibernate.criterion.DetachedCriteria; Yc~l Yz+b
import org.hibernate.criterion.Projections; U1/ww-!Z
import `}uM91;
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org.springframework.orm.hibernate3.HibernateCallback; {|<r7K1<
import %yKcp5_
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org.springframework.orm.hibernate3.support.HibernateDaoS )>Z@')Uk:
(;9fkqm%m
upport; b%@9j;
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import com.javaeye.common.util.PaginationSupport; ('BB9#\t
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public abstract class AbstractManager extends ^e =xEZD
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HibernateDaoSupport { /RhM6N
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privateboolean cacheQueries = false; yU7XX+cB7
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privateString queryCacheRegion; j1+I_
{(F}SF{
publicvoid setCacheQueries(boolean .ty2! .
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cacheQueries){ SLN OOEN
this.cacheQueries = cacheQueries; F>[^m Xw
} <.BY=z=H
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publicvoid setQueryCacheRegion(String <bhJ >
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queryCacheRegion){ MOB'rPIUI
this.queryCacheRegion = "~6&rt
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queryCacheRegion; fffWvf
} mN R}%s
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publicvoid save(finalObject entity){ km
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getHibernateTemplate().save(entity); 7pep\
} l 8GAZ*+
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publicvoid persist(finalObject entity){ XJS^{=/
getHibernateTemplate().save(entity); +Bt%W%_X
} [,~;n@jz
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publicvoid update(finalObject entity){ XC/M:2$
getHibernateTemplate().update(entity); 56NDU>j$
} 0BjP|API
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publicvoid delete(finalObject entity){ u^VQwu6?G
getHibernateTemplate().delete(entity); ^QHgc_oDm
} S!JLy&@
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publicObject load(finalClass entity, =G'J@[d{d
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finalSerializable id){ biQ~q$E
return getHibernateTemplate().load 4}YHg&@\d%
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(entity, id); &oK&vgcj
} [Mv'*.7
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publicObject get(finalClass entity, AVc|(~V
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finalSerializable id){ &&96kg3
return getHibernateTemplate().get b|@f!lA
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(entity, id); f~p[izt
} 6?0QzSpfC#
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publicList findAll(finalClass entity){ U\YzE.G1]S
return getHibernateTemplate().find("from = o1&.v2j
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" + entity.getName()); lOIf4
} 79'N/:.
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publicList findByNamedQuery(finalString 9\6ZdnEKu,
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namedQuery){ $*+UX
return getHibernateTemplate :C#(yp
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().findByNamedQuery(namedQuery); `hU2Ss~
} Novn#0a
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publicList findByNamedQuery(finalString query, P;p20+
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finalObject parameter){ r5!Sps3B
return getHibernateTemplate Ar[$%
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().findByNamedQuery(query, parameter); X]Ma:1+
} T`Qg+Q$
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publicList findByNamedQuery(finalString query, g; ZVoD
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finalObject[] parameters){ Uv=hxV[7y
return getHibernateTemplate :c&F\Q=
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().findByNamedQuery(query, parameters); zT _[pa)O`
} !}&f2!?.W
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publicList find(finalString query){ ,Z6\%:/
return getHibernateTemplate().find q+/7v9
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(query); 7Eett)4
} ,"Nfo`7
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publicList find(finalString query, finalObject Rr/sxR|0_
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parameter){ ^u[n!R\
return getHibernateTemplate().find w-M,@[G
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(query, parameter); Gh #$[5&`
} /MUa
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public PaginationSupport findPageByCriteria kX)Xo`^Ys
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(final DetachedCriteria detachedCriteria){ |X$O'Gf#n
return findPageByCriteria .Q^8_'ZG
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); :_y}8am;H~
}
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public PaginationSupport findPageByCriteria vUU)zZB~
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(final DetachedCriteria detachedCriteria, finalint {BA1C
(
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startIndex){ Anu`F%OzB
return findPageByCriteria `/0S]?a.{B
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(detachedCriteria, PaginationSupport.PAGESIZE, <.yL&$9
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startIndex); 7"c^$fj
} ^t'mfG|DV
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public PaginationSupport findPageByCriteria ~ojH$=K>d
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(final DetachedCriteria detachedCriteria, finalint B]o5HA<k
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pageSize, =I}8-AS~V
finalint startIndex){ p*_^JU(<p
return(PaginationSupport) g]hTz)8fF
im6Rx=}E{
getHibernateTemplate().execute(new HibernateCallback(){ E~y@ue:
publicObject doInHibernate XsVp7zk\
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(Session session)throws HibernateException { O~1vX9
Criteria criteria = O"D0+BK79e
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detachedCriteria.getExecutableCriteria(session); v7ShXX:
int totalCount = xElHYh(\
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((Integer) criteria.setProjection(Projections.rowCount (")IU{>c6
0"*!0s~
()).uniqueResult()).intValue(); ve [*t `
criteria.setProjection NR*s7>
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(null); /i${ [1
List items = 9HjtWQn
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criteria.setFirstResult(startIndex).setMaxResults 8N8N)#A[
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(pageSize).list(); bP4<q?FKcN
PaginationSupport ps = =%}++7#
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new PaginationSupport(items, totalCount, pageSize, tdl Y
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startIndex); ?-y!FD}m&
return ps; YL$#6d
} uEK9
}, true); <K$X>&Ts
} Q9UBxpDV:
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public List findAllByCriteria(final :KJG3j?
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DetachedCriteria detachedCriteria){ *5\k1-$
return(List) getHibernateTemplate Hq[vh7Lux
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().execute(new HibernateCallback(){ dFu<h
publicObject doInHibernate @435K'!
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(Session session)throws HibernateException { y?t2@f]!XK
Criteria criteria = cZ!%#Az
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detachedCriteria.getExecutableCriteria(session); ?f\;z<e|
return criteria.list(); `*A!vO8
} Qj?qWVapA
}, true); Z/|oCwR
} QWo_Zg0"
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public int getCountByCriteria(final IEx`W;V]K
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DetachedCriteria detachedCriteria){ Kc6p||<
Integer count = (Integer) 36NENzK
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getHibernateTemplate().execute(new HibernateCallback(){ V/=NIeSE
publicObject doInHibernate [<HU~PP
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(Session session)throws HibernateException { SMMV$;O{9
Criteria criteria = N W/RQ(
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detachedCriteria.getExecutableCriteria(session); -P+@n)?T6
return BCw5.@HK*
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criteria.setProjection(Projections.rowCount ?r~|B/]
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()).uniqueResult(); *PXlbb
} JGJXV3AT
}, true); xq?9w$
return count.intValue(); h";0i:
} @~4Q\^;NX
} e{ce
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用户在web层构造查询条件detachedCriteria,和可选的 iIOA5 4!o
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startIndex,调用业务bean的相应findByCriteria方法,返回一个
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PaginationSupport的实例ps。 >L\>Th{o
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ps.getItems()得到已分页好的结果集 ]Iku(<*Ya
ps.getIndexes()得到分页索引的数组 &P+7Um(
ps.getTotalCount()得到总结果数 _\HMF
ps.getStartIndex()当前分页索引 yfBVy8Sm
ps.getNextIndex()下一页索引 s0}OsHAj
ps.getPreviousIndex()上一页索引 d)'am
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 R)>/P{A-P
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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 'A0.(a5
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一下代码重构了。 d$>TC(E=t
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我把原本我的做法也提供出来供大家讨论吧: d(.e%[`
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首先,为了实现分页查询,我封装了一个Page类: 8|>$M
java代码: _j$"fg
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/*Created on 2005-4-14*/ `[hc{ynO|
package org.flyware.util.page; 4)L(41h
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/** TO&ohATp
* @author Joa RlRkw+%m
* d|GQZAEJEt
*/ \)\uAI-
publicclass Page { `1|#Za~e
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/** imply if the page has previous page */ :n'$Txf
privateboolean hasPrePage; 6jv_j[[
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/** imply if the page has next page */ ~r<@`[-L
privateboolean hasNextPage; J~=bW\^I
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/** the number of every page */ Tr}z&efY
privateint everyPage; z >EO Qe
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/** the total page number */ H .F-mm
privateint totalPage; X9W'.s.[Q
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/** the number of current page */
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privateint currentPage; uvNLm]*
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/** the begin index of the records by the current C,*3a`/2M^
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query */ 4o+SSS
privateint beginIndex; "4Joou"U
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/** The default constructor */ !n;0%"(FH
public Page(){ ^!Y]l
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} gMN>`Z`fV
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/** construct the page by everyPage K|i:tHF]@
* @param everyPage #[ei/p
* */ N>R\,n|I
public Page(int everyPage){ 9+:SS1_
this.everyPage = everyPage; {e'P*j
} se|>P=/
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/** The whole constructor */ OyI?P_0u
public Page(boolean hasPrePage, boolean hasNextPage, ?c G~M|@
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int everyPage, int totalPage, 0bG[pp$[
int currentPage, int beginIndex){ @nC][gNv
this.hasPrePage = hasPrePage; )b%t4~7
this.hasNextPage = hasNextPage; s ;3k#-w
this.everyPage = everyPage; {gL8s
this.totalPage = totalPage; y4\(ynk
this.currentPage = currentPage; u+5&^"72,
this.beginIndex = beginIndex;
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} \ltbiDP2
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/** yH=Hrz:<eM
* @return ^}w@&Bje
* Returns the beginIndex. (:(Imk;9
*/ #EG
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publicint getBeginIndex(){ Abw=x4d(i
return beginIndex; n-"(lWcp
} `49: !M$i
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/** {PGiNY%q
* @param beginIndex e/7rr~"|
* The beginIndex to set. w"Q/ 6#!K
*/ 2_/H,
publicvoid setBeginIndex(int beginIndex){ n 3eLIA{
this.beginIndex = beginIndex; BvnNAi
} AjYvYMA&
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/** '?Jz8iu-
* @return [ML|,kq!
* Returns the currentPage. #+"1">l
*/ 3wYhDxY1
publicint getCurrentPage(){ 67tB8X
return currentPage; B>;`$-
} im-XP@<
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/** ;hgRMkmz4<
* @param currentPage 1 u~Xk?
* The currentPage to set. ,I2x&Ys&.
*/ ?3_^SRW&a
publicvoid setCurrentPage(int currentPage){ @$7'{*
this.currentPage = currentPage; _'mK=`>u
} j5:/Gl8
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/** 3j6Am{9
* @return oHPh2b0
* Returns the everyPage. (|2:^T+
*/ Xk(p:^ R
publicint getEveryPage(){ ~LF/wx>
return everyPage;
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} h( DmSW
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/** D~zk2
* @param everyPage zHX7%x,Cq
* The everyPage to set. x+bC\,q
*/ >c@jl
publicvoid setEveryPage(int everyPage){ s?Z{LWZ@
this.everyPage = everyPage; XY,!vLjL
} xU F5
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/** z7s}-w,
* @return SUb:0GUa
* Returns the hasNextPage. n[gc`#7|{e
*/ _Wtwh0[r*
publicboolean getHasNextPage(){ 0TqIRUz "C
return hasNextPage; `sLD>@m
} sZ>0*S
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/** bo-lT-I
* @param hasNextPage d$HPpi1LL
* The hasNextPage to set. v[4-?7-
*/ ckkm}|&m
publicvoid setHasNextPage(boolean hasNextPage){ gs(ZJO1 /L
this.hasNextPage = hasNextPage; QT4&Ix,4T1
} he|.Ow
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/** C.RXQ`-P}
* @return H}cq|hodn
* Returns the hasPrePage. (H;,E-
*/ r8Z.}<j
publicboolean getHasPrePage(){ /], 9N
return hasPrePage; {ceY:49
} 6lm<>#_
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/** !>:]k?$b
* @param hasPrePage !
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* The hasPrePage to set. 0*,]`A=
*/ g'NR\<6A
publicvoid setHasPrePage(boolean hasPrePage){ :pLaxWus!
this.hasPrePage = hasPrePage; t8ORfO+
} Mu@(^zW
dN@C)5pm5`
/** [$@EQ]tt/
* @return Returns the totalPage. ujr"_ofI
* 9h"3u;/,
*/ 3b/J
publicint getTotalPage(){ U
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return totalPage;
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} 5}2148
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/**
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* @param totalPage sW&h?jdf
* The totalPage to set. >gDKkeLD
*/ \*Z:w3;r
publicvoid setTotalPage(int totalPage){ n`D-?]*
this.totalPage = totalPage; {Hz;*1?$k
} Ue=1NnRDkA
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} u6
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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 C#.27ah
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个PageUtil,负责对Page对象进行构造: J!H)[~2/
java代码: 4+Y9":<
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/*Created on 2005-4-14*/ )!5"\eys
package org.flyware.util.page; 0NXaAf:2Z
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import org.apache.commons.logging.Log; e09QaY
import org.apache.commons.logging.LogFactory; /a\]Dwj5
:JK+V2B$H
/** 1n#{c5T
* @author Joa c@$W]o"A
* yJ!,>OQ%'
*/ bLO^5` 6
publicclass PageUtil { P%ZU+ET
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privatestaticfinal Log logger = LogFactory.getLog pz]KUQ
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(PageUtil.class); 7lAn GP.;
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/** @e+qe9A|
* Use the origin page to create a new page 9w-;d=(Q
* @param page NYPjN9L
* @param totalRecords wdRk+
* @return _!k\~4U
*/ h YVy 65Ea
publicstatic Page createPage(Page page, int LGWQBEXw
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totalRecords){ Bb7Vf7>
return createPage(page.getEveryPage(), =!=DISPo
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page.getCurrentPage(), totalRecords); :Y4G^i
} +[#^c3x2
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/** l'?(4N
* the basic page utils not including exception c/,B ?
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handler *-s':('R
* @param everyPage ]gVW&3ZW
* @param currentPage `'ak/%Krh
* @param totalRecords ]F4|@+\9
* @return page 2l +t-
*/ tA-p!#V<k1
publicstatic Page createPage(int everyPage, int FZfhiIf
oi%IHX(`
currentPage, int totalRecords){ =l%|W[OO
everyPage = getEveryPage(everyPage); >x${I`2w
currentPage = getCurrentPage(currentPage); BsYJIKfW
int beginIndex = getBeginIndex(everyPage, r?WOum
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currentPage); da$ErN'{
int totalPage = getTotalPage(everyPage, |L6 +e*
lv&y<d;
totalRecords); nc:K!7:
boolean hasNextPage = hasNextPage(currentPage, }nWW`:t kx
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totalPage); I_na^sh*
boolean hasPrePage = hasPrePage(currentPage); %Pk@`t (3
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returnnew Page(hasPrePage, hasNextPage, 2bTM0-
everyPage, totalPage, DC=XPn/V
currentPage, *YWk.
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beginIndex); 0|~3\e/QV
} um$L;-2:
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bG
privatestaticint getEveryPage(int everyPage){ %F] :nk`
return everyPage == 0 ? 10 : everyPage; Og"\@n
} }z_7?dn/
U_5\FM
privatestaticint getCurrentPage(int currentPage){ ,/..f!bp
return currentPage == 0 ? 1 : currentPage; +qmV|$rmM
} %~qY\>
>>0c)uC|W
privatestaticint getBeginIndex(int everyPage, int ^vo]bq7
|3 v+&eVi
currentPage){ E^t}p[s
return(currentPage - 1) * everyPage; G4)X~.Fy
} ` MXGEJF
F vHd`
privatestaticint getTotalPage(int everyPage, int /@]@Tz@'
i}Cy q
totalRecords){ ]s~%1bd
int totalPage = 0; \rmge4`4
{iVmae
if(totalRecords % everyPage == 0) ehQ~+x
totalPage = totalRecords / everyPage; CL"q"
else oCuKmK8
totalPage = totalRecords / everyPage + 1 ; go5l<:9
-P=Hp/ELi
return totalPage; Z;J{&OJ3qM
} \m1jV>q
<k-hRs2d
privatestaticboolean hasPrePage(int currentPage){ +zSdP2s
return currentPage == 1 ? false : true; ^|=3sJ4[U
} r#/Bz5Jb*
l*n4d[0J
privatestaticboolean hasNextPage(int currentPage, JiCy77H
G>0hi1
int totalPage){ C/A~r
return currentPage == totalPage || totalPage == RTv zS]
is}Y+^j.
0 ? false : true;
7VAet
} ?K^~(D8(
/&G )IY]g
D^\2a;[AxA
} ~[4zm$R^
Z1M{5E
_hs\"W
-O?&+xIK&
ajALca4
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。 6*=7ifS
Q1?0]5
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 (Y$48@x
8S7 YVsDz"
做法如下: Rz!! ;<ye8
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 /V)4B4
Gu@Znh-D
的信息,和一个结果集List: dNgjM
Q
java代码: HVK./yqy
T&~7*j(|e
~TfQuIvQB
/*Created on 2005-6-13*/ 3eP7vy
package com.adt.bo; ,Frdi>7 ~
>PMLjXK
import java.util.List; R3Ka^l8R|
TkSeDP
import org.flyware.util.page.Page; 6b9&V`
!`EhVV8u-_
/** =
~^
* @author Joa F_C_K"[s
*/ [p[C45d=<
publicclass Result { y<A%&
E5F0C]hq
private Page page; ;IX*4E'4s
o:"^@3
private List content; m5rJY/
@%sr#YqY
/** bem-T`>'
* The default constructor T&PLvyBL
*/ XT0:$0F
public Result(){ a5xmIp@6
super(); K JX@?1"
} h1 (MvEt
+Jv*u8T'
/** ;_hL
* The constructor using fields &33.mdBH
* nfbq J
* @param page '{(/C?T
* @param content ^HasT4M+x
*/ lYMNx|PF
public Result(Page page, List content){ pRLs*/Bw
this.page = page; X0"f>.Lg
this.content = content; --9Z
} SJdi*>
2>bV+[@B
/** mv+K!T6
* @return Returns the content. Ud8*yB
*/ }.R].4gT
publicList getContent(){ c&JYbq
return content; !(wH}ti
} bb^$]lT'
bG6<=^
/** qm&Z_6Pw
* @return Returns the page. ;y{VdT
*/ J|BZ{T}d
public Page getPage(){ 0piBK=tE/
return page; P_w\d/3
} hIr$^%
6Q6l?!|W4
/** A|esVUo<3^
* @param content BOQeP/>
* The content to set. 0y3<Ho,+$
*/ gxku3<S
public void setContent(List content){ C,!}WB@VME
this.content = content; M:~/e8Xv
} (cj3[qq
MK<VjpP0(
/** Q&9%XF
uM
* @param page 0kD8w j%
* The page to set. VnJ-nfA
*/ !j3V'XU#Zn
publicvoid setPage(Page page){ ?"aj&,q+
this.page = page; s\`Vr;R:|
} /~LXY<-(
} $pT%7jV}
`37GVo4
WLAJqmC]
a#0GmK
Y"uFlHN&i
2. 编写业务逻辑接口,并实现它(UserManager, #c0
dZ
IKK<D'6
UserManagerImpl) a9E!2o+,
java代码: 4pF U` g=
vl@t4\@3
{tE/Jv $
/*Created on 2005-7-15*/ k:4?3zJI
package com.adt.service; fxDY:l
)Q\ZYCPOr
import net.sf.hibernate.HibernateException; P#H#@:/3
F GOa!G
import org.flyware.util.page.Page; L-d8bA
1>*]jj}
import com.adt.bo.Result; /S;o2\
v.1= TBh
/** 2`* %NJ
* @author Joa ,h2q37
*/ %uGA+ \b
publicinterface UserManager { cLlfncI
LeW.uh3.
public Result listUser(Page page)throws O#7ldF(
]tZ5XS
HibernateException; wN)R !6
N,ik&NIWy
} $EJ*x$
z1+rz%
P:k(=CzZ@J
g]xZ^M+
fC3IxlG
java代码: *:.0c
MatC2-aV1
*vhm
/*Created on 2005-7-15*/ !BEOeq@2.
package com.adt.service.impl; 8"LaP3U
ioi
import java.util.List; :,q3?l6
M{kPEl&Z
import net.sf.hibernate.HibernateException; e(
^9fg_SG
,.FTw,<
import org.flyware.util.page.Page; ;(0:6P8I
import org.flyware.util.page.PageUtil; &`L5UX
*A\NjXJl~
import com.adt.bo.Result; J-PzI FWd
import com.adt.dao.UserDAO; ,f?#i%EF&
import com.adt.exception.ObjectNotFoundException; jX&&@zMq
import com.adt.service.UserManager; QrA8KSLC
)N=b<%WD
/** ['km'5uZ^
* @author Joa ~POeFZ
*/ eBAB7r/7
publicclass UserManagerImpl implements UserManager { gy =`c MS@
"(efd~.]
private UserDAO userDAO; ` `;$Kr
3X!~*_iC
/** Ee|+uQ981>
* @param userDAO The userDAO to set. 3Xh&l[.
*/ #6H<JB
publicvoid setUserDAO(UserDAO userDAO){
.V.N^8(:a
this.userDAO = userDAO; >Au<y,Tw
} *>'R
R<
"tj#P
/* (non-Javadoc) 0KQ8;&a|
* @see com.adt.service.UserManager#listUser qBNiuV;*
,xh9,EpBk
(org.flyware.util.page.Page) 2@&|hd=-
*/ xRY5[=97
public Result listUser(Page page)throws -KNJCcBJ
blN1Q%m6
HibernateException, ObjectNotFoundException { "G,*Z0V5
int totalRecords = userDAO.getUserCount(); H);'\]_'x
if(totalRecords == 0) ,){0y%c#y
throw new ObjectNotFoundException cY"^3Ot%^
OXacI~C
("userNotExist"); Q]7Q
page = PageUtil.createPage(page, totalRecords); a2rv4d=
List users = userDAO.getUserByPage(page); u9gr@06
returnnew Result(page, users); .)3 2WD%
} L,D>E
~/x42|t
} `?@7 KEl>
}6bLukv
*@&
"MZ/M
-0X> y
0\#Q;Z2
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 *Z:PB%d5
l =yHx\
询,接下来编写UserDAO的代码: JJ~?ON.H
3. UserDAO 和 UserDAOImpl: _Nn!SE
java代码: Xdq,
=;
19.cf3Dh
".)_kt[
/*Created on 2005-7-15*/ K(d!0S
package com.adt.dao; C#~MR+;
f$>orVm%.
import java.util.List; eFio,
-"zu"H~t4
import org.flyware.util.page.Page; '/H(,TM
[KH?5C
import net.sf.hibernate.HibernateException; QB[s8"S
`0^i
#
/** 2f!oA~|2
* @author Joa lz (,;I'x
*/ re!8nuBsA
publicinterface UserDAO extends BaseDAO {
/Xz4q!Ul
#& wgsGV8C
publicList getUserByName(String name)throws $)3PF
doc
HibernateException; 6
b}feEh$!
r(i)9RI+(
publicint getUserCount()throws HibernateException; >p*HXr|o$
2mZ/
3u
publicList getUserByPage(Page page)throws :*@|"4
3c ^=<i
%
HibernateException; R6Mxdm2P}
`U_>{p&x
} 6Y)^)dOi
sK-|xU.
K}`p_)(
b*F~%K^i$
Y"kS!!C>[
java代码: = )l: ^+q
'Y{ux>
xO<-<sRA
/*Created on 2005-7-15*/ D2:a
package com.adt.dao.impl; T{4fa^c2J
Ym{%"EB
import java.util.List; ilp;@O6
11<@++,i
import org.flyware.util.page.Page; liw 9:@+V
g~hk-nXL.
import net.sf.hibernate.HibernateException;
e1^{
import net.sf.hibernate.Query; cvV?V\1f
sx<+ *Trl
import com.adt.dao.UserDAO; K:
o|kd
mz$Wo *FB
/** f93rY<
* @author Joa renmz,dJ,
*/ bOSYr<R&
public class UserDAOImpl extends BaseDAOHibernateImpl sJI-
xDA,?i;T
0
implements UserDAO { q8xc70: R
5@>4)dk\
/* (non-Javadoc) e|5B1rMM
* @see com.adt.dao.UserDAO#getUserByName TQ\wHJ
v(@+6#&
(java.lang.String) JIbzh?$aD
*/ .`Old{<
publicList getUserByName(String name)throws ?^48Zq6wM
{`Fx~w;i
HibernateException { U??f<
String querySentence = "FROM user in class F{*9[jY
^W[B[Y<k
com.adt.po.User WHERE user.name=:name"; Q0q)n=i}]
Query query = getSession().createQuery ( ln
nL+YL
(querySentence); \p@nH%@v
query.setParameter("name", name); ;sck+FP7w
return query.list(); RSPRfYU/
} Ca5Sc, no
34m' ]n
/* (non-Javadoc) LF9aw4:>Ou
* @see com.adt.dao.UserDAO#getUserCount() PD}SPOA`U3
*/ {GX
&)c4
publicint getUserCount()throws HibernateException { # McK46B z
int count = 0; R(/[NvUb
String querySentence = "SELECT count(*) FROM iUxDEt[t*
lN)Y
user in class com.adt.po.User"; VO @
4A6
Query query = getSession().createQuery >Oi2gPA
~aqT~TL_
(querySentence); `Dz]z_
count = ((Integer)query.iterate().next MgH1d&R
c_-" Qo
()).intValue(); 1%/ NL?8#
return count; p-Rm,xyL%
} ^T}}4I_Y
`u p-m=zA
/* (non-Javadoc) J I+KS
* @see com.adt.dao.UserDAO#getUserByPage mI?* Z%>g
J:g<RZZ1
(org.flyware.util.page.Page) V`R)#G>IH%
*/ ~ F?G5cN5
publicList getUserByPage(Page page)throws KD%xo/Z.
(^tr}?C
HibernateException { oRT
String querySentence = "FROM user in class nl)_`8=
/`4v"f0V
com.adt.po.User"; L)kb (TH
Query query = getSession().createQuery Rm,[D)D^0N
#RR:3ZPZC
(querySentence); XI@6a9Uk
query.setFirstResult(page.getBeginIndex()) Pp1zW3+Q
.setMaxResults(page.getEveryPage()); %jbJ6c
return query.list(); t-*VsPy
} [|:QE~U@
"t(1tWO1o
} 5YTb7M
!q~X*ZKse
R/ALR
":UWowJO
>u9id>+
至此,一个完整的分页程序完成。前台的只需要调用 ]+}ZfHp
F:[7^GQZ{
userManager.listUser(page)即可得到一个Page对象和结果集对象 u#a%(
jgo e^f
的综合体,而传入的参数page对象则可以由前台传入,如果用 9]]!8_0=r
vh9kwJyT
webwork,甚至可以直接在配置文件中指定。 ]k[Q]:q
ewb*?In
下面给出一个webwork调用示例: V;>9&'Z3
java代码: wFK:Dp_^
CTh1+&Pa
>:w?qEaE
/*Created on 2005-6-17*/ azao`z
package com.adt.action.user; );Tx5Z}
]4Nvh\/P9
import java.util.List; K(-G: |
;Ri 3#*a=
import org.apache.commons.logging.Log; x2
w8zT6M
import org.apache.commons.logging.LogFactory; >X;xIyRL
import org.flyware.util.page.Page; ,|e} Y
[
u/z,92mmS
import com.adt.bo.Result; Hnfvo*6d.e
import com.adt.service.UserService; R^jlEt\&P
import com.opensymphony.xwork.Action; >}ro[x`K
r/UYC"K3
/** Oq #o1>
* @author Joa 5Z*
b(R
*/ >}-~rZ
publicclass ListUser implementsAction{ (3e;"'k
?wGiog<Q{
privatestaticfinal Log logger = LogFactory.getLog "sFW~Y
?F!EB4E\y}
(ListUser.class); l'|E,N>X
Z6 t E{/
private UserService userService; ^{),+S
9uuta4&uI
private Page page; f&6w;T=
gE\A9L~b
privateList users; [?;`x&y~y
n"(7dl?
/* VT'0DQ!NIq
* (non-Javadoc) y:qx5Mi
* ?g5iok {
* @see com.opensymphony.xwork.Action#execute() V]r hr
*/ [m~b[ZwES
publicString execute()throwsException{ 7;^((.]ln
Result result = userService.listUser(page); Bk&-1>cY
page = result.getPage(); YkSuwx@5_q
users = result.getContent(); )V=0IZi
return SUCCESS; 1#/6r :
} \^Ep>Pq`]
"]v
uD
/** 4S'[\ZJO
* @return Returns the page. `tX@8|
*/ JRD8Lz]Q3
public Page getPage(){ iOl%-Y
return page; <'W=]IAV
} _8al
p Z"o@';!
/** S)+CTVVE
* @return Returns the users. RV}GK
L>gn
*/ )^&,Dj
publicList getUsers(){ tzPC/?
return users; ~eHRlXL'
} &D]&UQf
#hpIyy%n
/** 10?qjjb&
* @param page 6nc0=~='$
* The page to set. )9MrdVNv
*/ o/WC@!wg K
publicvoid setPage(Page page){ QGXQ {
this.page = page; #Gd7M3
} m*`cuSU|o
7^Na9]PY
/** !Qcir&]C>
* @param users 3B;}j/h2
* The users to set. TMqY4;UeL
*/ 2yvVeo&3
publicvoid setUsers(List users){ Gbn4*<N
this.users = users; @7fm1b
} j AQU~Ol_
*!Y-!
/** vnTq6:f#M
* @param userService Hng!'
* The userService to set. jQ?LHUE
*/ 9s(i`RTM
publicvoid setUserService(UserService userService){ |0kXCq
this.userService = userService; ./7v",#*.'
} g,=^'D
} mL$f[
e=7W7^"_
Pxqiv9D<R
~,gLplpG0
nkRK+~>
上面的代码似乎看不出什么地方设置了page的相关初值,事实上, 3b@VY'P
.TJ">?
可以通过配置文件来进行配置,例如,我想每页显示10条记录,那 =*O=E@]
> ws!5q
么只需要: v,jhE9_O0
java代码: e #M iaX
!R6ApB4ZI
csDQva\
<?xml version="1.0"?> Xu6K%]i^
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork bAiJn<
nvt$F%+
1.0//EN" "http://www.opensymphony.com/xwork/xwork- Yb6q))Y
|1Hc&
1.0.dtd"> ! Mo`^t
Y@%`ZPJ
<xwork> c+2sT3).D
kiX%3(
<package name="user" extends="webwork- .$0Pr%0pWI
Kam]Mn'
interceptors"> YE\K<T
jH
1TZPef^y
<!-- The default interceptor stack name 1
i3k
pj;
I)-d/
--> 2h q>T&8
<default-interceptor-ref uR_F,Mp?%u
J +q|$K6
name="myDefaultWebStack"/> <lj\#'G3
{/|qjkT&W
<action name="listUser" g5Td("&n
4pPI'd&/7
class="com.adt.action.user.ListUser"> d!V$Y}n
<param N4wA#\-
O('Nn]wo~9
name="page.everyPage">10</param> x=*L-
<result URw5U1
J@]k%h
name="success">/user/user_list.jsp</result> jg_n 7
</action> W&C-/O,m
8\#
^k#X
</package> N wtg%;
o`6|ba
</xwork> O+"ac /r
!9 f4R/ ?
61@EDIYPc
W)4QOS&
R#eg^7HfX
4l @)K9F
这样就可以通过配置文件和OGNL的共同作用来对page对象设置初值 WG5W0T_
7bF*AYM
了。并可以通过随意修改配置文件来修改每页需要显示的记录数。 ZnfNQl[
n7l%gA*
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 qSD9P ue
T3 pdx~66
926Tl
GoE
'L
J/ W{/E>;
我写的一个用于分页的类,用了泛型了,hoho Qh`:<KI
1RqgMMJL
java代码: >/^#Drwb!i
0LL c 1t>}
#YK5WTn5
package com.intokr.util; H{(]9{
<Kt3PyF
import java.util.List; 'C>U=cE7
;>"nn
VW
/** + WDq=S
* 用于分页的类<br> Qe$k3!
* 可以用于传递查询的结果也可以用于传送查询的参数<br> i8PuC^]
* ;[$n=VX`
* @version 0.01 h(' )"
* @author cheng %y<]Yzv.
*/ }Je>;{&%
public class Paginator<E> { ]}PV"|#K{c
privateint count = 0; // 总记录数 \2kPq>hu
privateint p = 1; // 页编号 K@:m/Z}|4
privateint num = 20; // 每页的记录数 z#Nl@NO&
privateList<E> results = null; // 结果 N "Wqy
" I+p
/** {nMAm/kyj
* 结果总数 P?ep]
*/ Qt+:4{He
publicint getCount(){ }e]f
return count; XbXA+ey6
} ^TFs;|..
KMK`F{
publicvoid setCount(int count){ !Pj/7JC0
this.count = count; C>QIrZu
} -yx/7B5@
s0W2?!>)
/** /Cr/RG:OX
* 本结果所在的页码,从1开始 W WG /k17
* V'gw\mcb
* @return Returns the pageNo. #-#NqX:
*/ )Y]/^1hx
publicint getP(){ r/:%}(7;
return p; ANMg
} ,?-\
x6
bKbp?-]
/** yy2I2Bv
* if(p<=0) p=1 ;N=G=X|}
* ?.bnIwQe
* @param p ?Dsm~bkX[
*/ -$a>f4]
publicvoid setP(int p){ ljJ>;g+
if(p <= 0) ; y.E!
p = 1; 3Rv7Qx
this.p = p; @xWdO,#
} )R)a@op
4&X*pL2;
/** w
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* 每页记录数量 w!3>N"em
*/ ]<w:V`(
publicint getNum(){ pa]" iZz
return num; =tdSq"jh
} `$RA< 3
~Gv#iRi>
/** zA+@FR?
* if(num<1) num=1 -=}3j&,\R
*/ /.Jb0h[W1
publicvoid setNum(int num){ z01>'
if(num < 1) )mcEQ -!b
num = 1; "5|Lz) =
this.num = num; i76 Yo5
} pK&I^r
@ GDX7TPV
/** _7)F
?
* 获得总页数 )LHj+B
*/ b\55,La
publicint getPageNum(){ pxINw>\Qv
return(count - 1) / num + 1; RuRt0Sd3
} pd@; b5T
Es5p}uh.[Y
/** wzWbB2Mb5
* 获得本页的开始编号,为 (p-1)*num+1 quu*xJ;Ci
*/ ~[PKcEX
publicint getStart(){ ]rBM5~
return(p - 1) * num + 1; Z+:D)L
} vq'c@yw;
V L( <
/** BNGe
exs@
* @return Returns the results. u62 )QJE
*/ E">T*ao
publicList<E> getResults(){ dWRrG-'
return results; #&!G"x7
} (X[2TT3j!
cd@.zg'sYn
public void setResults(List<E> results){ :K.4 n
this.results = results; D$k8^Vs
} eARk
QV
;."<m
public String toString(){ 0(>rG{u
StringBuilder buff = new StringBuilder OJ>.-"
|VH!)vD
(); /L=(^k=a.;
buff.append("{"); 5t:8.%<UK
buff.append("count:").append(count); HaNboYW_K
buff.append(",p:").append(p); E;\M1(\u
buff.append(",nump:").append(num); MLVB^<qkeH
buff.append(",results:").append L-i>R:N4
c$E)P$<j
(results); >O9sk
buff.append("}"); Tt# bg1
return buff.toString();
&wH:aD
} #~ v4caNx
UV7%4xM5v
} M7}Q=q\9
3-Bl
B;zt#H4