Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 yhJ@(tu.Gd
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 ~TtiO#,t
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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 /9X7A;O
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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 7+*WH|Z@
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分页支持类: O6Y0XL
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java代码: :T~ [
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package com.javaeye.common.util; >Q*Wi
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import java.util.List; pR_9NfV{
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publicclass PaginationSupport { 2AdDIVYC
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publicfinalstaticint PAGESIZE = 30; unxqkU/<Z
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privateint pageSize = PAGESIZE; $cgcX
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privateList items; tJmTBsn
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privateint totalCount; ;VK.2^jW!
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privateint[] indexes = newint[0]; rl.}%Ny
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privateint startIndex = 0; nt<]d\o0
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public PaginationSupport(List items, int P<-@h1p,
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totalCount){ ry]l.@o;
setPageSize(PAGESIZE); W*G<X.Hf
setTotalCount(totalCount); QGz|*]
setItems(items); g)B]FH1
setStartIndex(0); OrW
} u?EN
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public PaginationSupport(List items, int r_d!ikOT(
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totalCount, int startIndex){ ^rz_f{c]-
setPageSize(PAGESIZE); L},_.$I?
setTotalCount(totalCount); :'ptuY
setItems(items); CN?gq^
setStartIndex(startIndex); p4QU9DF
} s#MPX3itK
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public PaginationSupport(List items, int %2h>-.tY
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totalCount, int pageSize, int startIndex){ |BYRe1l6l
setPageSize(pageSize); iRBfx
setTotalCount(totalCount); GX%g9f!O
setItems(items); )B*t
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setStartIndex(startIndex); kf9X$d6
} m[2gdJK
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publicList getItems(){ bK7J} 8hH
return items; &3&HY:yF
} g{LP7D;6
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publicvoid setItems(List items){ V~#tuv
this.items = items; z!\*Y
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} r|Z{-*`
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publicint getPageSize(){ 0}9h]X'
return pageSize; sq]F;=[5
} <Z$J<]I
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publicvoid setPageSize(int pageSize){ yQrD9*t&g
this.pageSize = pageSize; 7:~_D7n
} q\)-BXw:
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publicint getTotalCount(){ Ca-j?bb!
return totalCount; 1x^GWtRp
} D'4\*4is
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publicvoid setTotalCount(int totalCount){ V)4J`xg^
if(totalCount > 0){ 4K74=r),i
this.totalCount = totalCount; *ui</+
int count = totalCount / x^CS"v7
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pageSize; =V5%+/r +f
if(totalCount % pageSize > 0) 5-M-X#(
count++; AwN!;t_0+N
indexes = newint[count]; !'Kjx
for(int i = 0; i < count; i++){ LQ% `c
indexes = pageSize * \NC3'G:Ii
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i; N g,j#
} }7X%'Bg=M
}else{
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this.totalCount = 0; >d6| ^h'0
} adw2x pj
} .(vwIb8\_
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publicint[] getIndexes(){ M3AXe]<eC1
return indexes; Pc9H0\+Xk
} zreU')a
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publicvoid setIndexes(int[] indexes){ ite~E5?#
this.indexes = indexes; 0$njMnB2l
} #;<Y[hR{P
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publicint getStartIndex(){ W9)&!&<o
return startIndex; 9FX-1,Jx
} ~s{$WL&
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publicvoid setStartIndex(int startIndex){ f 1d?.)
if(totalCount <= 0) /O9EQ Pm(
this.startIndex = 0; KmF]\:sMD
elseif(startIndex >= totalCount) E.f%H(b
this.startIndex = indexes r=4eP(w=
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[indexes.length - 1]; nP$9CA
elseif(startIndex < 0) ElXFeJ%[G
this.startIndex = 0; c%&>p||
else{ IK]d3owA
this.startIndex = indexes H>C=zo,oiC
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[startIndex / pageSize]; yHGADH0B
} W%J\qA
} @@%ataUSBT
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publicint getNextIndex(){ #1[u(<AS
int nextIndex = getStartIndex() + =QsYXK7Mn4
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pageSize; a9 G8q>h]O
if(nextIndex >= totalCount) 4m)n+ll
return getStartIndex(); [gB+C84%%
else F\!
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return nextIndex; {8aTV}Ha2
} B1STG L`nK
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publicint getPreviousIndex(){ _j3f Ar(V
int previousIndex = getStartIndex() - |{8Pb3#U
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pageSize; {8OCXus3m
if(previousIndex < 0) |^aKs#va
return0; "oD[v
else 36NpfTW
return previousIndex; v:U-6W_)|
} 4Up/p&1@
}'.m*#Y
} 4z? l
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抽象业务类 $?Wb}DU7_L
java代码: ys~x$
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/** rKn~qVls
* Created on 2005-7-12 &vJH$R
*/ :>*7=q=
package com.javaeye.common.business; r,udO,Yi=c
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import java.io.Serializable; TN.rrop`#g
import java.util.List; /\Ef%@
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import org.hibernate.Criteria; @VBcJ{e,
import org.hibernate.HibernateException; "#] $r
import org.hibernate.Session; :0ep(<|;
import org.hibernate.criterion.DetachedCriteria; OnK4] S5
import org.hibernate.criterion.Projections; R8Tx[CJ5
import z}@7'_iJ
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org.springframework.orm.hibernate3.HibernateCallback; liZxBs
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import hj:,S|
*Uh!>Iv;
org.springframework.orm.hibernate3.support.HibernateDaoS RpK@?[4s
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upport; K8~d^G
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import com.javaeye.common.util.PaginationSupport; 8QK&_n*
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public abstract class AbstractManager extends Th%zn2R B
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HibernateDaoSupport { (ZGbhMK
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privateboolean cacheQueries = false; y(&Ac[foS}
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privateString queryCacheRegion; y2v^-q3
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publicvoid setCacheQueries(boolean F:VIzyMq<
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cacheQueries){ :Al!1BJQ
this.cacheQueries = cacheQueries; @,}UWU
} C+]I@Go'Tk
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publicvoid setQueryCacheRegion(String S3#>9k;p
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queryCacheRegion){ s.#`&Sd>
this.queryCacheRegion = z{6Z
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queryCacheRegion; h 0|s
} >usL*b0%
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publicvoid save(finalObject entity){ ':q p05t
getHibernateTemplate().save(entity); *R"/ |Ka
} O<I-
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publicvoid persist(finalObject entity){ 7,MR*TO,
getHibernateTemplate().save(entity); s*4dxnS_8
} 3
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publicvoid update(finalObject entity){ vIvIfE
getHibernateTemplate().update(entity); Y@v>FlqI{
} YQ}o?Q$z
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publicvoid delete(finalObject entity){ NRuNKl.v
getHibernateTemplate().delete(entity); TrNF=x>
} 0"R|..l/
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publicObject load(finalClass entity, |:o4w
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finalSerializable id){ %xW"!WbJ|
return getHibernateTemplate().load YR70BOxK
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(entity, id); 6b,V;#Anj
} [;N'=]`
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publicObject get(finalClass entity, >~f]_puT
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finalSerializable id){ N mG#
return getHibernateTemplate().get QPx^_jA
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(entity, id); +t.b` U`-
} xo)P?-
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publicList findAll(finalClass entity){ :m;p:l|W
return getHibernateTemplate().find("from 54,er$$V
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" + entity.getName()); @W<m4fi
} ^OdP4m(
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publicList findByNamedQuery(finalString K"6vXv4QO
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namedQuery){ #Z #-Ht
return getHibernateTemplate x^ni1=kU
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().findByNamedQuery(namedQuery); V9vTsmo(
} Iv *<La
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publicList findByNamedQuery(finalString query, nTas~~Q
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finalObject parameter){ =I<R! ZSN
return getHibernateTemplate aXVFc5C\
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().findByNamedQuery(query, parameter); t1".0
} baasGa3}s
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publicList findByNamedQuery(finalString query, ?< />Z)
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finalObject[] parameters){ D9df=lv
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return getHibernateTemplate ~[ jQ!tz
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().findByNamedQuery(query, parameters); H}!r|nG
} ' QG?nu
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publicList find(finalString query){ 1\Xw3prH
return getHibernateTemplate().find pmM9,6P4@
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(query); F2WKd1U
} W!X@
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publicList find(finalString query, finalObject 45e~6",
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parameter){ LLo;\WGZ
return getHibernateTemplate().find Y73C5.dNcE
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(query, parameter); oRFq@g
} |>Vb9:q9Po
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public PaginationSupport findPageByCriteria 97]E1j]
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(final DetachedCriteria detachedCriteria){ "g|#B4'e
return findPageByCriteria NUZl`fu1Z4
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); |=w@H]r
} y `UaB3q
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public PaginationSupport findPageByCriteria 2HdC |$_+
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(final DetachedCriteria detachedCriteria, finalint 8Wx=p#_
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startIndex){ d~H`CrQE*
return findPageByCriteria 8r{.jFGv
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(detachedCriteria, PaginationSupport.PAGESIZE, fl(wV.Je|
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startIndex); s#11FfF`
} o4X{L`m
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public PaginationSupport findPageByCriteria +2{Lh7Ks
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(final DetachedCriteria detachedCriteria, finalint Nc`L;CP
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pageSize, WE?5ehEme
finalint startIndex){ ]/Pn
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return(PaginationSupport) fex@,I&
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getHibernateTemplate().execute(new HibernateCallback(){ siI;"?
publicObject doInHibernate Upe%rC(
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(Session session)throws HibernateException { M >u_4AY
Criteria criteria = QV!up^Zso
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detachedCriteria.getExecutableCriteria(session); ]DcFySyv
int totalCount = }tz7b#
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((Integer) criteria.setProjection(Projections.rowCount iMlWM-wz>O
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()).uniqueResult()).intValue(); icgfB-1|i
criteria.setProjection l**X^+=$
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(null); U6K|fYN`
List items = \D4:Nt#
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criteria.setFirstResult(startIndex).setMaxResults (zk"~Ud
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(pageSize).list(); s AkdMo
PaginationSupport ps = A"]YM'.
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new PaginationSupport(items, totalCount, pageSize, V`- 9m$
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startIndex); >7|VR:U?B
return ps; Ac@VGT:9
} *w&e\i|7
}, true); uT"rq:N
} G\i9:7 `
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public List findAllByCriteria(final OXA7w.^
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DetachedCriteria detachedCriteria){ 8LKiS
return(List) getHibernateTemplate 8tL~FiHb"
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().execute(new HibernateCallback(){ h`q1
publicObject doInHibernate s;e\ pt
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(Session session)throws HibernateException { 1Mzmg[L8
Criteria criteria = [JiH\+XLPs
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detachedCriteria.getExecutableCriteria(session); 6Mf0`K
return criteria.list(); ?9/G[[(
} o&%g8=n%
}, true); .*oU]N%K=
} i5Ggf"![
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public int getCountByCriteria(final **%37
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DetachedCriteria detachedCriteria){ P
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Integer count = (Integer) fhiM U8(&
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getHibernateTemplate().execute(new HibernateCallback(){ Ml_^
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publicObject doInHibernate o-5TC
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(Session session)throws HibernateException { Cdn J&N{
Criteria criteria =
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detachedCriteria.getExecutableCriteria(session); pBHRa?Y5
return x5Bk/e'
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criteria.setProjection(Projections.rowCount ZK,G v
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()).uniqueResult(); oJ^P(] dw
} X?O[r3<
}, true); K;?+8(H
return count.intValue(); y[;>#j$
} l?e.9o2-
} I7onX,U+
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用户在web层构造查询条件detachedCriteria,和可选的 Q &8-\
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 J.a]K[ci
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PaginationSupport的实例ps。 sJZiI}Xc
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ps.getItems()得到已分页好的结果集 9up3[F$
ps.getIndexes()得到分页索引的数组 t@(HF-4~=
ps.getTotalCount()得到总结果数 %{W6PrY{
ps.getStartIndex()当前分页索引 1MFbQs^
ps.getNextIndex()下一页索引 x}4q {P5$
ps.getPreviousIndex()上一页索引 9 hl_|r~%*
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 awRX1:T#;O
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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 _`X:jj>
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一下代码重构了。 P \I|,
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我把原本我的做法也提供出来供大家讨论吧: X$
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首先,为了实现分页查询,我封装了一个Page类: 3]hWfj1m2
java代码: :FF=a3/"6
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/*Created on 2005-4-14*/ 8ag!K*\V<
package org.flyware.util.page; [E_9V%^
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/** bA 2pbjg=
* @author Joa @ Qe0! (_=
* btB%[]
*/ 9c],<;{'
publicclass Page { 637:
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ceA9){
/** imply if the page has previous page */ }V>T M{
privateboolean hasPrePage; Om&Dw|xG8
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/** imply if the page has next page */ vO=fP_
privateboolean hasNextPage; cQ|NJ_F{1
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/** the number of every page */ ZCw]m#lS
privateint everyPage; e20-h3h+
{
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/** the total page number */ ooGM$U
privateint totalPage; Gj*9~*xm(
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/** the number of current page */ Cx"sw
}
privateint currentPage; xno\s.H%]
=1!
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/** the begin index of the records by the current _F{C\}
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query */ =N@t'fOr
privateint beginIndex; }]TxlSp!;
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/** The default constructor */ CLSK'+l
public Page(){ Xj*Wu_
hZ3bVi)L\
} 5;?yCWc
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/** construct the page by everyPage ,Q B<7a+I
* @param everyPage G3]4A&h9v~
* */ E7hhew
public Page(int everyPage){ rNM;ZPF#
this.everyPage = everyPage; ?%86/N>
} w!CNRtM:~
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/** The whole constructor */ B!yr!DWv
public Page(boolean hasPrePage, boolean hasNextPage, 3T
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|{;G2G1[
int everyPage, int totalPage, s{++w5s
int currentPage, int beginIndex){ VQI3G
this.hasPrePage = hasPrePage; K,]=6Rj
this.hasNextPage = hasNextPage; R+| h w;
this.everyPage = everyPage; )[ ,A_3E
this.totalPage = totalPage; g0
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this.currentPage = currentPage; .hiSw
this.beginIndex = beginIndex; -di o5a
} 0c&+|>!
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/** VL^EHb7
* @return d _
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* Returns the beginIndex. Q\)F;: |
*/ 'yth'[
publicint getBeginIndex(){ B *vM0
return beginIndex; $(9U @N9E
} E4!Fupkpf
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/** +"(jjxJm
* @param beginIndex !BI;C(,RL
* The beginIndex to set. #g=XUZ/"
*/ V]N?6\Op
publicvoid setBeginIndex(int beginIndex){ Qd6F H2Pl
this.beginIndex = beginIndex; =xrv~
} E9}C #
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/** zL it
* @return P4?glh q#
* Returns the currentPage. 7rA;3?p)
*/ 8Y3I0S
publicint getCurrentPage(){ y]imZ4{/
return currentPage; }%z
} aT<q=DO
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/** R3!t$5HG
* @param currentPage jal-9NV)!
* The currentPage to set. HThcn1u~^b
*/ J;%Xfx]
publicvoid setCurrentPage(int currentPage){ _|]x2xb)
this.currentPage = currentPage; m,S{p<-h
} .ByuN
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/** oE~RySX
* @return K#xvu1U
* Returns the everyPage. P$sxr
*/ AEuG v}#
publicint getEveryPage(){ )i<j XZ:O
return everyPage; IAEAhqp
} 4=.so~9odX
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/** :!/8Hv
* @param everyPage bfO=;S]b!
* The everyPage to set. `kr?j:g
*/ a>)f=uS
publicvoid setEveryPage(int everyPage){ w:l"\Tm
this.everyPage = everyPage; nd(S3rct&
} -DCbko
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/** m3ff;,
* @return {^'HL
* Returns the hasNextPage. 4~=l}H>&
*/ 0ksa
publicboolean getHasNextPage(){ ?}7p"3j'z
return hasNextPage; <| &Npd'
} ,
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/** ^J d
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* @param hasNextPage v@Ox:wl>
* The hasNextPage to set. zT[!o
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*/ Hefg[$m
publicvoid setHasNextPage(boolean hasNextPage){ LF7SS;&~f
this.hasNextPage = hasNextPage; 8X0z~&
} (ik\|y% A
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/** \Roz$t-R|f
* @return x`?3C"N:<
* Returns the hasPrePage. 4fzZ;2sl}
*/ akT6^cP^
publicboolean getHasPrePage(){ >3_Gw4S*H
return hasPrePage; BZxvJQ
} Q,9oKg
j.kG};f
/** 9/;P->wy
* @param hasPrePage z] Ue|%K
* The hasPrePage to set. Ru~j,|0r4
*/ d[35d J7F
publicvoid setHasPrePage(boolean hasPrePage){ _2nx^E(pd
this.hasPrePage = hasPrePage; ;$tSb ~K+
} Z8oK2Dw
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/** ASfaX:ke
* @return Returns the totalPage. ]~nKK@Rw
* :aQt;C6Z>
*/ m6djeOl
publicint getTotalPage(){ Wm3X[?V
return totalPage; 7)k\{&+P
} km40qO@3
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/** F>cv<l
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* @param totalPage @K]|K]cby
* The totalPage to set. ]fD}
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*/ 8*fv'
publicvoid setTotalPage(int totalPage){ HKr
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this.totalPage = totalPage; :c[L3rJl
} %[yJ4WL
9S -9.mvop
} Q^(b)>?r;
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上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 x=jK:3BF
X|8c>_}
个PageUtil,负责对Page对象进行构造: d M-%{
java代码: ukY"+&
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/*Created on 2005-4-14*/ f`/x"@~H5
package org.flyware.util.page; ,iq4Iw
#V}IvQl|
import org.apache.commons.logging.Log; p^u:&Quac
import org.apache.commons.logging.LogFactory; 4g7)i L^#~
Y#3c }qb
/** ,u
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* @author Joa AFfAtu
* 0AV c
*/ \_U$"/$4VH
publicclass PageUtil { Z:7fV5b(
p6WX9\qS(
privatestaticfinal Log logger = LogFactory.getLog 6i*sm.SDw
4,0{7MLgK
(PageUtil.class); ;Q&5,<
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/** -Vhw^T1iV
* Use the origin page to create a new page &=k,?TJO>
* @param page ilva,WFa^
* @param totalRecords fg{n(TE"8
* @return X~i<g?]
*/ hiw|2Y&`
publicstatic Page createPage(Page page, int pO.2<
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totalRecords){ Yir
[!{
return createPage(page.getEveryPage(), 0{[,E.
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page.getCurrentPage(), totalRecords); ,'iE;o{Tu
} S/I /-Bp~
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/** .-X8J t
* the basic page utils not including exception :U(A;U1,
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handler K}U-w:{
* @param everyPage WSY}d
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* @param currentPage PAOJ\U
* @param totalRecords SC])?h-Fw
* @return page 9!DQ~k%
*/ H]jhAf<h
publicstatic Page createPage(int everyPage, int vFK<J Sk!
"2T#MO/
currentPage, int totalRecords){ bnLPlf
everyPage = getEveryPage(everyPage); 7(
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currentPage = getCurrentPage(currentPage); Y7[jqb1D
int beginIndex = getBeginIndex(everyPage, -\n@%$M]G
'oC)
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currentPage); _H=Uwi_g
int totalPage = getTotalPage(everyPage, <kd1Nrr!p
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totalRecords); '!a'ZjYyi
boolean hasNextPage = hasNextPage(currentPage, d$AWu{y
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totalPage); E1U",CMU
boolean hasPrePage = hasPrePage(currentPage); Ezv
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returnnew Page(hasPrePage, hasNextPage, a+T.^koY
everyPage, totalPage, K>l~SDcZ3
currentPage, 78H'ax9m
yqiq,=OvP
beginIndex); qc~iQSI
} kd$D 3S^{
d6sye^P
privatestaticint getEveryPage(int everyPage){ _Z,\Vw:\F
return everyPage == 0 ? 10 : everyPage; g!z&~Z:
} 1q1jZqno
?_"ik[w}
privatestaticint getCurrentPage(int currentPage){ t\j*}# S
return currentPage == 0 ? 1 : currentPage; E'.7xDN
} 3CGp`~Zf
a,#j =
privatestaticint getBeginIndex(int everyPage, int B[?CbU
Ktm4 A O
currentPage){ c#tjp(-
return(currentPage - 1) * everyPage; Y.ToIka{
} A^EE32kbm
SrK<fAkx
privatestaticint getTotalPage(int everyPage, int Y<ql49-X
9
ea\vZ
totalRecords){ ; XN{x
int totalPage = 0; ([LSsZ]sj
df #$9-
if(totalRecords % everyPage == 0) ZH)="qx[
totalPage = totalRecords / everyPage; &&RimoIeo
else 0f>5(ek
totalPage = totalRecords / everyPage + 1 ;
4J([6<
pDCeQ6?
return totalPage; KX7>^Bt&k
} 6,9>g0y'NG
PJrtMAcKq
privatestaticboolean hasPrePage(int currentPage){ xDoC(
return currentPage == 1 ? false : true; JOLaP@IPT
} cFnDmtI:
l.bYE/F0&
privatestaticboolean hasNextPage(int currentPage, pWsDzb6?%
o\pVp bB
int totalPage){ 2nIw7>.}f
return currentPage == totalPage || totalPage == Jh[UtYb5
GMl;7?RA
0 ? false : true; - kwXvYu\
} _ T):G6C8
-rli(RR)|
SHo$9+
} /&+tf*
^ tg<K
wInh~p
%vhnl'
Z//+Gw<'
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 sAD}#Zw$
|CZ@te)>
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 r_6ZO&
in- HUG
做法如下: "#oHYz3D
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 zZ323pq
YCM]VDx4u1
的信息,和一个结果集List: #c?j\Y9nz
java代码: +sUFv)!4
#"\gLr_:m
t*T2Z-!P
/*Created on 2005-6-13*/ }m;,Q9:+m^
package com.adt.bo; o-OHjFfB
iv;Is[<o
import java.util.List; M`i\VG
{I #]@,
import org.flyware.util.page.Page; mFaZio0GK
D(RTVef
/** B1C-J/J
* @author Joa d]6#m'U
*/ #& Rw&
publicclass Result { 1\>^m
Ix=}+K/
private Page page; Vq?p|wy
,+xB$e
private List content; O-I[igNl
f;gw"onx8F
/** T<p !5`B 1
* The default constructor EYEnN
*/ h+&OQ%e=8
public Result(){ `FTy+8mw
super(); =mpVYA
} v`zJb00DT
gSUcx9f]
/** 9:1Q1,-i!-
* The constructor using fields hB>oJC
* iQ
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* @param page C3],n
* @param content ~SF<,-Kg
*/ I3mGo
public Result(Page page, List content){ lXiKY@R#
this.page = page; kDN:ep{/
this.content = content; ,>-< (Qi
} g/+C@_&m
4^~(Mh- Mw
/** OFv%B/O
* @return Returns the content. TQ*1L:X7M&
*/ ^_u kLzP9
publicList getContent(){ 48qV>Gwf
return content; `A^"%@j
} C:C}5<fkx
DB:+E|vSD
/** /.M N
* @return Returns the page.
!0@Yplj
*/ U4-g^S[
public Page getPage(){ ZUR6n>r
return page; 4?7W+/~<&
} ahOM CZF|
ps%q9}J
/** *q".-u!D[
* @param content <|+Ex
* The content to set. $yYO_ZBiy
*/ db6b-Y{
public void setContent(List content){ ie\"$i.98H
this.content = content;
4/1d&Sg
} WP+oFkw>
f Tl<p&b
/** D+z?wuXk
* @param page qA$*YIlK
* The page to set. b6F4>@gjg
*/ ^1aAjYFn
publicvoid setPage(Page page){ ReI/]#Us
this.page = page; Hp|_6hO 2
} 4 G-wd
} "a"]o
-VTkG]{`Ir
'BPp ]R#{
7MHKeLq
&LVn6zAba
2. 编写业务逻辑接口,并实现它(UserManager, i2(1ki/|O
s,n0jix@
UserManagerImpl) ^!z[t\$
java代码: <$~mE9a6
i Ae<&Ms
hn=[1<#^(
/*Created on 2005-7-15*/ 5v}8org
package com.adt.service; Vq;A>
?yR&/a
import net.sf.hibernate.HibernateException; &n?^$LTPY
9;Ox;;w
import org.flyware.util.page.Page; :Q_<Z@2Y{
M9@ri ^x
import com.adt.bo.Result; TGe;HZ
T {Uc:Z
/** c|62jY"$-2
* @author Joa l0cA6b
*/ ~-m "
publicinterface UserManager { \z7SkZt,GT
rT5Ycm@
public Result listUser(Page page)throws 9Z'8!$LYg
q51Uf_\/
HibernateException; p)3U7"q
@u%_1
} EC8b=B<DE
.dQQoyR+O
+H#U~p$
F>[,zN
;Uu(zhbj
java代码: me ks
RcF
mP P`xL?T
sHl>$Qevz
/*Created on 2005-7-15*/ 3?Pn6J{O
package com.adt.service.impl; '07P&g-
1u(.T0j7f
import java.util.List; a5!Fv54
$3uKw!z
import net.sf.hibernate.HibernateException; MFm"G
z`FCs,?K
import org.flyware.util.page.Page; B0WJ/)rK<
import org.flyware.util.page.PageUtil; .h5[Q/*h
.]7Qu;L
import com.adt.bo.Result; )R
2.
import com.adt.dao.UserDAO; HcV"X,7S
import com.adt.exception.ObjectNotFoundException; s nnbb0J
import com.adt.service.UserManager; ]Ww?QhJ
tl'9IGlc
/** IGFR4+
* @author Joa Gkv{~?95
*/ )}'U`'q
publicclass UserManagerImpl implements UserManager { | j a-
i?:_:"^x
private UserDAO userDAO; Ox'/`Mppw
>P $;79<
/** /<8N\_wh
* @param userDAO The userDAO to set. OdY=z!Fls
*/ m[@Vf9
publicvoid setUserDAO(UserDAO userDAO){ adi[-L#
this.userDAO = userDAO; 9>rPe1iv
} %T9 sz4V
DHT&,=
/* (non-Javadoc) TdGnf
* @see com.adt.service.UserManager#listUser BQ2wnGc
BC;:
(org.flyware.util.page.Page) ,b;{emX h
*/ _#}n~}d
public Result listUser(Page page)throws PF7&p~O(Z
JA_BKA
HibernateException, ObjectNotFoundException { 7ei|XfR
int totalRecords = userDAO.getUserCount(); 3^~KB'RZ
if(totalRecords == 0) V{&rQ@{W
throw new ObjectNotFoundException `TPOCxM Mo
\3jW~FV
("userNotExist"); z.VyRB i0
page = PageUtil.createPage(page, totalRecords); -"[<ek
List users = userDAO.getUserByPage(page); A4?+T+#d
returnnew Result(page, users); lP!;3iJ B
} t
6^l `6:p
[j:[
} F0UVo
13&0rLS
.eO?Z^
h"[+)q%L
dN}#2Bo=
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 Uyr3dN%*r
fiN3xP]V
询,接下来编写UserDAO的代码: eDZ8w
3. UserDAO 和 UserDAOImpl: 0W()lQ
java代码: `\6?WXk3T
rJInj>|{=
eBO@7F$
/*Created on 2005-7-15*/ z>06hBv(?Y
package com.adt.dao; "AhTH.ZP
G>+1*\c
import java.util.List; ~|AwN [
r]Ff{la5
import org.flyware.util.page.Page; @hImk`&[N
#vqo -y7@
import net.sf.hibernate.HibernateException; ([VV%ovZ
lM[XS4/TRa
/** b4""|P?L
* @author Joa /Y2/!mU</
*/ F[!ckes<bB
publicinterface UserDAO extends BaseDAO { kY&h~Q
=@5x"MOz
publicList getUserByName(String name)throws X*7\lf2
@AYo-gf
HibernateException; =?(~aV
Mf#83<&K
publicint getUserCount()throws HibernateException; UYtuED
aRJ>6Q}
publicList getUserByPage(Page page)throws ?P7]u>H
q(5+xSg"gK
HibernateException; |J~eLh[d
x/:4{
} :ECi+DxBK
M8b4NF_&
@v*/R%rv t
5Fm=/o1
|uH%6&\
java代码: Px>va01n
Q9`QL3LQD
a%Jx
`hx
/*Created on 2005-7-15*/ 5Y3i|cj
package com.adt.dao.impl; X}6#II
*$M'`vj:
import java.util.List; V8~jf-\$b
Sj(F3wY
import org.flyware.util.page.Page; STA4 p6
='E$-_
import net.sf.hibernate.HibernateException; oQj=;[
import net.sf.hibernate.Query; Ij'NC C
47T}0q,
import com.adt.dao.UserDAO; ^-M^gYBR
1SV^ ){5I
/** NS,5/t
* @author Joa Z2bcCIq4
*/ i$KpDXP\
public class UserDAOImpl extends BaseDAOHibernateImpl OlQ,Ce
S|GWcSg
implements UserDAO { '?yCq$&
Ab1/.~^
/* (non-Javadoc) FCc=e{
* @see com.adt.dao.UserDAO#getUserByName -6Mm#sX
B )JM%r
(java.lang.String) O;]?gj 1@
*/ Sb:T*N0gS
publicList getUserByName(String name)throws vG2b:[W
<39!G7ny
HibernateException { lKEa)KF[
String querySentence = "FROM user in class Y#01o&f0n
8 )\M:s~7&
com.adt.po.User WHERE user.name=:name"; qOG}[%<^n7
Query query = getSession().createQuery [W,-1.$!dM
7>
Pgc
(querySentence); K$REZe
query.setParameter("name", name); )DUL)S
return query.list(); y/@iT8$rp
} !=*.$4
(a6?s{(
/* (non-Javadoc) m^{
xd2
* @see com.adt.dao.UserDAO#getUserCount() )-/gLZsx
*/ ELh3^
publicint getUserCount()throws HibernateException { kYxS~Kd<
int count = 0; &}`K^5K|O:
String querySentence = "SELECT count(*) FROM aP>37s
1{2eY%+C
user in class com.adt.po.User"; !|m9|
Query query = getSession().createQuery ! ]Mc4!E
\`,xgC9K
(querySentence); Ca $c;
count = ((Integer)query.iterate().next " B@jfa%
pyW u9
()).intValue(); =<<3Pkv7@
return count; e"+dTq8W
} hQgN9S5P
S9Yt 1qb
/* (non-Javadoc) 3#<*k>1G?
* @see com.adt.dao.UserDAO#getUserByPage /axTh
QlW=_Ymv{
(org.flyware.util.page.Page) <kD#SV%"
*/ n!N\zx8
publicList getUserByPage(Page page)throws (3EUy"z-
M'1HA
HibernateException { :nQp.N*p
String querySentence = "FROM user in class RFG$X-.e
"6I[4U"@
com.adt.po.User"; &(&
Query query = getSession().createQuery '0+$ m=
\-.
Tg!Q6
(querySentence); J^I7BsZ
query.setFirstResult(page.getBeginIndex()) -rDz~M+
.setMaxResults(page.getEveryPage()); Ds5NAp:x
return query.list(); ^@}#me@
} 9[|4[3K
GH3#E*t+[
} Qp!Y.YnPd_
*PM}"s
IF?xnu
-WT3)On
e!o(g&wBj
至此,一个完整的分页程序完成。前台的只需要调用 cj(X2L
hswTn`f
userManager.listUser(page)即可得到一个Page对象和结果集对象 <FmBa4ONU
XS0V:<+,
的综合体,而传入的参数page对象则可以由前台传入,如果用 {~GR8
U
WaYO1*=
webwork,甚至可以直接在配置文件中指定。 FWTx&Ip
wR7aQg
下面给出一个webwork调用示例: c d%hW
java代码: _@ i>s,
3B,QJ&
$ly0h W
/*Created on 2005-6-17*/ }~*rx7p
package com.adt.action.user; lvufk VG|
XN;/nU
import java.util.List; pVOI5>f\
?*K<*wBw#
import org.apache.commons.logging.Log; ,ZK]i CGk
import org.apache.commons.logging.LogFactory; b]`^KTYK
import org.flyware.util.page.Page; Jqg3.2q
aW@oE
~`
import com.adt.bo.Result; PqhlXqX9
import com.adt.service.UserService; !s-/0ugZ
import com.opensymphony.xwork.Action; w<d*#$[,*
&`PbO
/** j+1KNH
* @author Joa YkbO&~.
*/ DM2Q1Dh3
publicclass ListUser implementsAction{ YZ[%uArm
&"j@79Ym1~
privatestaticfinal Log logger = LogFactory.getLog !P" ?
B+D`\ Nl o
(ListUser.class); fSV5
n|]N7 b'
private UserService userService; h[l{ 5Z*
U,3d) ]Zy&
private Page page; .S|-4}G(6
3LrsWAz'
privateList users; j_pw^I$C
&HxT41pku
/* v>^jy8$
* (non-Javadoc) |+/$ g.
* )_O.{$
to
* @see com.opensymphony.xwork.Action#execute() Y\u_+CG*
*/ /.-m}0h|W-
publicString execute()throwsException{ aL$j/SC
Result result = userService.listUser(page); B*Cb6'Q
page = result.getPage(); 4sd-zl$Of
users = result.getContent(); U$$3'n
return SUCCESS; 8DT@h8tA
}
?zE<
.jum "va%
/** -4`sqv ]
* @return Returns the page. QX/]gX
*/ 3YRBI|XO
public Page getPage(){ di<B ~:l58
return page; sWW\bK0B4
} y7;
5xF?q
T]X{@_
/** T Xl\hL\+
* @return Returns the users. L)G">T;
*/ r
&c_4%y
publicList getUsers(){ [+7"{UvT
return users; Fi k@hu
} V*kznm
d'q;+jnP
/** R]VTV7D
* @param page |3|wdzV
* The page to set. 7rPLnB]
*/ PoY>5
publicvoid setPage(Page page){ @d
P~X
this.page = page; Wb'*lT0=
} 1YFAr}M
x/[8Wi,yB
/** K5+!(5V~
* @param users %)dI2 J^Xf
* The users to set. :3 PG f
*/ 7ozYq_ $
publicvoid setUsers(List users){ TwwIt5_fN
this.users = users; 1+FYjh!2t
} @ p"NJx"
hF9B?@n?B
/** 1S^'C2/b
* @param userService &?v#| qIh
* The userService to set. {z-NlH
*/ }7&\eV{qU
publicvoid setUserService(UserService userService){ 4Z],+?.[
this.userService = userService; H7J`]nr6
} $TFTIk*uU
} lWIv(%/@
@#1cx
I@+lFG
,$o-C&nC
_4~k3%w\`l
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, 8\P
JSr
i:R!T,
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 "{mt?
)ZviS.
么只需要: UVnrDhd!0
java代码: V~JBZ}`TG<
*(>Jd|C
*j/uihY
<?xml version="1.0"?> ^CO#QnB @
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork kaV%0Of]
}t}38%1i
1.0//EN" "http://www.opensymphony.com/xwork/xwork- M2a}x+5'
dzpj9[
1.0.dtd"> ~igRg~k:/
_J+]SNk
<xwork> il=?o f\,i
'/n\Tg+
<package name="user" extends="webwork- Xk
5oybDI
@_G` Ok4
interceptors"> rK*hTjVn
m]E o(P4+
<!-- The default interceptor stack name ,&-S?|
}#YIl@E
--> aYqqq|
<default-interceptor-ref 9 Zs#Ky/
(di)`D5Q
name="myDefaultWebStack"/> OE5 X8DqQe
_QD/!~O
<action name="listUser" yIM.j;5:~5
yl[2et
class="com.adt.action.user.ListUser"> b;SFI^
<param YL;SxLY
,ZLG7e
name="page.everyPage">10</param> /IrKpmbq
<result L;L2j&i%v)
9Kq<\"7Bmz
name="success">/user/user_list.jsp</result> N+ak[axN
</action> $z~jnc
M|$H+e }:
</package> Y}85J:q]
W^-hMT]uD
</xwork> hQ\#Fhu7
B/kcb(5v
&3!i@2d;3f
Iwnj'R7:
`#-p,NElV
-Pv P
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 ,^UcRZ8.H
bEBZ!ghU
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。 h[vAU 9f)
ke{DFqh
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 $Vd?K@W[h
clij|?O
8 ))I$+
FjK Ke7
=M Q2sb
我写的一个用于分页的类,用了泛型了,hoho X20<r?^,,
:7zI3Ml@7
java代码: 1c1e+H
EU`'
8*4
\"<GL;
package com.intokr.util; yQ72v'
\ x>NB
import java.util.List; }xpe
g)2m$#T&s
/** Fj[ dO&
* 用于分页的类<br> 3JwSgc b
* 可以用于传递查询的结果也可以用于传送查询的参数<br> t[L2'J.5
* UMnR=~.
* @version 0.01 3<V.6'*k
* @author cheng %D%e:se
*/ ua6*zop
public class Paginator<E> { PW(_yB;
privateint count = 0; // 总记录数 ?S;et2f
privateint p = 1; // 页编号 ~:'gvR;x
privateint num = 20; // 每页的记录数 J
tn&o"C
privateList<E> results = null; // 结果 o(S^1j5
B8P@D"u
/** 3|z;K,`Fw
* 结果总数 XFLjVrX[
*/ :Kt{t46)
publicint getCount(){ *J*zml3
return count; ;h*"E(Pp
} )o}=z\M-bN
uC <|T
publicvoid setCount(int count){ [kU[}FT
this.count = count; gwkZk-f\p
} S1 R #]
?w|\7T.?
/** URj%
J/jD
* 本结果所在的页码,从1开始 hfP(N_""S
* VH$\ a~|
* @return Returns the pageNo. `UzCq06rJ1
*/ M[&.kH
publicint getP(){ HzFt
return p; exa}dh/uC
} j[Hg]
DVeF(Y3&
/** @Reh?]# v
* if(p<=0) p=1 P^o"PKA
* *(_ON$+3
* @param p -h.3M0
*/ t 's5~
publicvoid setP(int p){ /eI,]CB'z
if(p <= 0) n^I|}u\
p = 1; 'h+4zvI"8
this.p = p; sIQMUC[!
} 0Zp<=\!;
.*clY
/** 42H#n]Y
* 每页记录数量 -qr:c9\px
*/ 'p{Y{
$Q
publicint getNum(){ E!oJ0*@
return num; PT=2LZ
} !Dhfr{
eQ4B5B%j/x
/** \t7zMp
* if(num<1) num=1 +q>C}9s3
*/ & t @
publicvoid setNum(int num){ rUJSzLy
if(num < 1) ygu?w7
num = 1; '~!l(&X
this.num = num; +&@l{x(,
} r]K0
]h@B
0v,`P4_k
/** YH:W]
* 获得总页数 r>D[5B
*/ ]mDsUZf<
publicint getPageNum(){ #|2g{7g*
return(count - 1) / num + 1; qoyGs}/I8
} g^|_X1{
S7\jR%pb
/** M4$4D?
* 获得本页的开始编号,为 (p-1)*num+1 Kk"B501
*/ TQyFF/K
publicint getStart(){ +HVG5l
return(p - 1) * num + 1; wNlV_
} 'e8d["N
@a{v>)
/** S@rsQ@PA
* @return Returns the results. FPM}:c4
*/ 9dhFQWz"
publicList<E> getResults(){ YfYL?G
return results; u8)r
W
} ;z=C^'
:8/M6-EK
public void setResults(List<E> results){ 1Y"y!\t7G
this.results = results; GCmVmOdKr
} 7H@Cy}a
zz''FmedF
public String toString(){ -V)5Tr=
StringBuilder buff = new StringBuilder ?f%DVK d
$f@-3/V6{
(); ?&t|?@
buff.append("{"); H'(o}cn7~
buff.append("count:").append(count); 8`R}L
buff.append(",p:").append(p); bKbpI>;[
buff.append(",nump:").append(num); d%|#m)
buff.append(",results:").append !D]6Cq
d3q/mg 5a
(results); 4pHPf<6
buff.append("}"); JT+lWhy
return buff.toString(); $1`t+0^k
} lKD<
mf_9O
} H0Gp mKYW
"7u"d4h-:(
H@bmLq