Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 d?zSwLsl
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 yf&g\ke
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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 i2=- su
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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 D=e*rrL7a
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。 Q:A#4Z
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分页支持类: HpnF,4A>
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java代码: q$:1Xkl
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package com.javaeye.common.util; `"5Ub,~
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import java.util.List; B)0/kY7c
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publicclass PaginationSupport { ) /raTD
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publicfinalstaticint PAGESIZE = 30; 6S`_L
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privateint pageSize = PAGESIZE; %*D=ni#(sT
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privateList items; z|#*c5Y9w
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privateint totalCount; KF%BX~80C
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privateint[] indexes = newint[0]; G6G Bqp6|
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privateint startIndex = 0; @{/)k%U
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public PaginationSupport(List items, int .?Eb{W)^br
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totalCount){ ]s\r3I]
setPageSize(PAGESIZE); *:%&z?<Fw
setTotalCount(totalCount); !0;AFv`\
setItems(items); Y{}
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setStartIndex(0); fn}E1w
} @:N8V[*u
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public PaginationSupport(List items, int zL"e .
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totalCount, int startIndex){ m?e/MQr
setPageSize(PAGESIZE); ~74Sq'j9Wt
setTotalCount(totalCount); 25X|N=}
setItems(items); .p[uIRd`
setStartIndex(startIndex); Kb; *"@LX
} WtOjPW
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public PaginationSupport(List items, int T?8BAxC?K
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totalCount, int pageSize, int startIndex){ f"Sp.'@
setPageSize(pageSize); KuR]X``2
setTotalCount(totalCount); Y@FYo>0O
setItems(items); \BHZRytQF
setStartIndex(startIndex); ,rB(WKU
} [ V.67_~
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publicList getItems(){ 9z(SOzZn
return items; }B0[S_mw
} <"3q5ic/Z
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publicvoid setItems(List items){ 72nZ`u
this.items = items; ChiIQWFE
} iv*RE9?^
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publicint getPageSize(){ ex>7f%\
return pageSize; 9\8ektq}Z
} R27'00(Z0
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publicvoid setPageSize(int pageSize){ mP)bOAU
this.pageSize = pageSize; zyPb\/
} Wl| i$L)7
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publicint getTotalCount(){ 7Z>vQ f B
return totalCount; >CvhTrPI
} ka_m
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publicvoid setTotalCount(int totalCount){ Snkb^Kt
if(totalCount > 0){ ffP]U4
this.totalCount = totalCount; rN1]UaT
int count = totalCount / ;hQ[-
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pageSize; ag'hHFV
if(totalCount % pageSize > 0) @`[e1KQ
count++; k$$SbStD
indexes = newint[count]; ]xRR/S4
for(int i = 0; i < count; i++){ i!YfR]"}
indexes = pageSize * ?`+VWa[,e
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} (wu'FFJp#
}else{ "}()/
this.totalCount = 0; "](Q2
} wR_mJMk_
} <zXG}JuL@T
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publicint[] getIndexes(){ ?NA$<0
return indexes; P%R!\i
} ?s, oH
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publicvoid setIndexes(int[] indexes){ (BY 0b%^
this.indexes = indexes; lJ3VMYVrUP
} V7WL Gy.,
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publicint getStartIndex(){ ,$`}Rf<
return startIndex; t?9J'.p
} ?)9L($VVD
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publicvoid setStartIndex(int startIndex){ `,4yGgD!4
if(totalCount <= 0) q{h,}[U=
this.startIndex = 0; 0er|QC
elseif(startIndex >= totalCount) SY
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this.startIndex = indexes t,YRM$P
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[indexes.length - 1]; DOyO`TJi
elseif(startIndex < 0) M4Cb(QAVP
this.startIndex = 0; h1S)B|~8
else{ (?Ko:0+*
this.startIndex = indexes .6MG#N
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[startIndex / pageSize]; YT-ua{.^
} ;MeY@*"{
} gw)z*3]~s
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publicint getNextIndex(){ R+.4|1p
int nextIndex = getStartIndex() + 4L>8RiiQE;
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pageSize; }"+"nf5h
if(nextIndex >= totalCount) h GA2.{
return getStartIndex(); rn
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else T[4xt,[a
return nextIndex; @7}XBg[pI
} igL5nE=n
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publicint getPreviousIndex(){ +788aK,{#
int previousIndex = getStartIndex() -
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pageSize; 0V6, &rTF
if(previousIndex < 0) wfO-bzdw
return0; xD*Zcw(vj~
else oL9<Fi
return previousIndex; L{~ ]lUo
} ft7M9<#v
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} od#Lad@p
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抽象业务类 H,
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java代码: X.{xHD&_
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/** sDs.da#*2
* Created on 2005-7-12 ac\aH#J_nC
*/ hqeknTGsIn
package com.javaeye.common.business; (}F@0WYT^O
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import java.io.Serializable; }c||$
import java.util.List; cAN8'S(s1
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import org.hibernate.Criteria; .WSn Y71
import org.hibernate.HibernateException; .oM- A\!
import org.hibernate.Session; '{0O!y[H6
import org.hibernate.criterion.DetachedCriteria; YKUAI+ks
import org.hibernate.criterion.Projections; 1<~n2}
import CnuM=S:
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org.springframework.orm.hibernate3.HibernateCallback; ] K&ca
import H.M:
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org.springframework.orm.hibernate3.support.HibernateDaoS \4qF3#
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upport; =W2.Nc
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import com.javaeye.common.util.PaginationSupport; +|;Ri68
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public abstract class AbstractManager extends q2|x$5
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HibernateDaoSupport { +Y*4/w[
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privateboolean cacheQueries = false; aNM*=y`
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privateString queryCacheRegion; xN$V(ZX4
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publicvoid setCacheQueries(boolean d$o m\@
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cacheQueries){ |H=5Am
this.cacheQueries = cacheQueries; n[y=DdiKGS
} .+Q1h61$T
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publicvoid setQueryCacheRegion(String T-n>+G{
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queryCacheRegion){ z1tD2jL _
this.queryCacheRegion = pqv l,G5
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queryCacheRegion; E\Wd*,/v)
} _`C|K>:
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publicvoid save(finalObject entity){ Z 9cb
getHibernateTemplate().save(entity); *fd:(dN|
} ?r]0 %W^
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publicvoid persist(finalObject entity){ S&=@Hj-
getHibernateTemplate().save(entity); ZH=Bm^
} zI"&g]TV5
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publicvoid update(finalObject entity){ P\[K)N/ 1
getHibernateTemplate().update(entity); gzK/ l:
} rx]Q,;"
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publicvoid delete(finalObject entity){ [GM!@6U
getHibernateTemplate().delete(entity); ZJ)>gV
} 1IgTJ" \
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publicObject load(finalClass entity, F*z>B >{)
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finalSerializable id){ >f9Q&c$R
return getHibernateTemplate().load %/U'Wu{*
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(entity, id); |VE.khq#
} \p\p~FVS
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publicObject get(finalClass entity, <Qbqxw
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finalSerializable id){ R))4J
return getHibernateTemplate().get ?TDmW8G}J
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(entity, id); taVK&ohWx
} U/HF6=Wot
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publicList findAll(finalClass entity){ $rjm MSxi
return getHibernateTemplate().find("from bQ?Vh@j(M
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" + entity.getName()); 6P9#6mZ
} [$>@f{:
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publicList findByNamedQuery(finalString \/wk!mWV@
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namedQuery){ :hB6-CZkqN
return getHibernateTemplate A[Ce3m
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().findByNamedQuery(namedQuery); b
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} rCGKE`H
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publicList findByNamedQuery(finalString query, v!S(T];)
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finalObject parameter){ 2nFr?Y3g,
return getHibernateTemplate (Q&jp!WU
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().findByNamedQuery(query, parameter); C{-Dv-<A>
} h^."wv
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publicList findByNamedQuery(finalString query, E9.1~
)
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finalObject[] parameters){ ,ueA'GZ
return getHibernateTemplate *|+$7j
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().findByNamedQuery(query, parameters); 5P('SFq'=
} s}^W2
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publicList find(finalString query){ #5{lOeN
return getHibernateTemplate().find Q\^BOdX^`
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(query); tuo'Uk)
} :K \IS `
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publicList find(finalString query, finalObject N>j*{]OY+{
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parameter){ OtZtl*5
return getHibernateTemplate().find !cO<N~0*5x
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(query, parameter); wC<FF2T
} TYxi&;w
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public PaginationSupport findPageByCriteria 'F1<m^
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(final DetachedCriteria detachedCriteria){ x;7p75Wm
return findPageByCriteria esv<b>`R
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); }V+&o\4
} ,+5!1>\
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public PaginationSupport findPageByCriteria ?G5,x
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(final DetachedCriteria detachedCriteria, finalint YL4yT`*
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startIndex){ "W}+~Sn
return findPageByCriteria 9\r5&#<(I
*;
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(detachedCriteria, PaginationSupport.PAGESIZE, y0t-e
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startIndex); 0w$1Yx~C
} aTLr%D:Ka
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public PaginationSupport findPageByCriteria %)r1?H} #%
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(final DetachedCriteria detachedCriteria, finalint #/K71Y
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pageSize, Nu; 9
finalint startIndex){ Z3 na .>Z
return(PaginationSupport) erV&N,cI
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getHibernateTemplate().execute(new HibernateCallback(){ M[Jy?b)
publicObject doInHibernate i:^
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(Session session)throws HibernateException { Js,.$t
Criteria criteria = `b5pa `\4
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detachedCriteria.getExecutableCriteria(session); G7HvA46
int totalCount = .!1E7\
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((Integer) criteria.setProjection(Projections.rowCount s.!gsCQme
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()).uniqueResult()).intValue(); 4L2TsuLw
criteria.setProjection lHgmljn5u
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(null); `[4{]jX+<
List items = Z@#kivcpz
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criteria.setFirstResult(startIndex).setMaxResults ,HW[l.v
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(pageSize).list(); X4v0>c
PaginationSupport ps = OWHHN<
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new PaginationSupport(items, totalCount, pageSize, OmECvL'Z
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startIndex); #$-`+P
return ps; H[iR8<rhQ
} KQrG|<J
}, true);
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} vj<JjGP
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public List findAllByCriteria(final b U>.Bp]
, *Z!Bd8
DetachedCriteria detachedCriteria){ Al}%r85
return(List) getHibernateTemplate Ykj+D7rA:
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().execute(new HibernateCallback(){ ncij)7c)u
publicObject doInHibernate p w`YMk
* @'N/W/8
(Session session)throws HibernateException { R-Z)0S'ZR
Criteria criteria = $)M5@KT
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detachedCriteria.getExecutableCriteria(session); b,RQ" {
return criteria.list(); P?YcZAJT*
} kCU(Hi`Q
}, true); :.fm LL
} xAAwH@ +
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public int getCountByCriteria(final .|3&lb6
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DetachedCriteria detachedCriteria){ Fpy-?U
Integer count = (Integer) *Ag,/Cm]
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getHibernateTemplate().execute(new HibernateCallback(){ l>jNBxB|/A
publicObject doInHibernate -f8iq[F5
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(Session session)throws HibernateException { g,5Tr_
Criteria criteria = ;Z{jol
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detachedCriteria.getExecutableCriteria(session); ABnJ{$=n#
return _{YUWV50}
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criteria.setProjection(Projections.rowCount =$Sd2UD
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()).uniqueResult(); p6W|4_a?
} lH1gWe
}, true); J0x)NnWJ
return count.intValue(); Meo.
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} /~;om\7r
} D1f}g
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用户在web层构造查询条件detachedCriteria,和可选的 8iUj9r_
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 5}"9)LT@@w
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PaginationSupport的实例ps。 @PyZ u7'
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ps.getItems()得到已分页好的结果集 me&'BQ
ps.getIndexes()得到分页索引的数组 JY6^pC}*
ps.getTotalCount()得到总结果数 :c`Gh< u
ps.getStartIndex()当前分页索引 vAjvW&'g
ps.getNextIndex()下一页索引 (E]q>'X
ps.getPreviousIndex()上一页索引 ~~X-$rtU
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 Ud'/
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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 \d}>@@U&
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一下代码重构了。 LF\HmKM,
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我把原本我的做法也提供出来供大家讨论吧: /K\]zPq
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首先,为了实现分页查询,我封装了一个Page类: nv/'C=+L
java代码: $ucA.9pJ
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/*Created on 2005-4-14*/ z6;6 o!ej
package org.flyware.util.page; 'nSo0cyQ
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/** 5l4YYwd>v
* @author Joa jPa"|9A
* V3<H8pL
*/ CWw#0
publicclass Page { b ]u01T-
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/** imply if the page has previous page */
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privateboolean hasPrePage; 85Red~-M
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/** imply if the page has next page */ r6gfxW5
privateboolean hasNextPage; ME.a * v
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/** the number of every page */ dh
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privateint everyPage; xY>@GSO1
rc`}QoB)R
/** the total page number */ _ UGR+0'Q\
privateint totalPage; 5)iOG#8qJ
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/** the number of current page */ z1S
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privateint currentPage; 6&`hf >
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/** the begin index of the records by the current &hu>yH>j
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query */ !\5w<*p8
privateint beginIndex;
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/** The default constructor */ y,s`[=CT
public Page(){ h yK&)y?~
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} ?!HU$>
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/** construct the page by everyPage !QSj*)V#
* @param everyPage ^xm%~
* */ Mqv[7.|
public Page(int everyPage){ cp$GP*{@
this.everyPage = everyPage; "Tz'j}< 9C
} Fj4>)!^kM
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/** The whole constructor */ N> xdX5
public Page(boolean hasPrePage, boolean hasNextPage, j9xu21'!%
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int everyPage, int totalPage, h?'~/@
int currentPage, int beginIndex){ U*4r<y9R
this.hasPrePage = hasPrePage; %z~=Jz^
this.hasNextPage = hasNextPage; 55Y a(E
this.everyPage = everyPage; 7z q@T]
this.totalPage = totalPage; <.".,Na(J0
this.currentPage = currentPage; i936+[
this.beginIndex = beginIndex; V:h7}T95
} O',Vce$
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/** _Wqy,L;J
* @return ;2 P
* Returns the beginIndex. bEm9hFvd
*/ 8PR\a!"
publicint getBeginIndex(){ L3=5tuQ[5
return beginIndex; Qk72ra)
} +/ rt'0o
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/** 2Gh&h(
* @param beginIndex lg
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* The beginIndex to set. R*/s#*gmL
*/ F3[,6%4v
publicvoid setBeginIndex(int beginIndex){ Q[{RNab
this.beginIndex = beginIndex; 5]xSK'6W
} niqknqW<t
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/** p(6 sN=
* @return P ; h8
* Returns the currentPage. ?N^1v&Q
*/ ?4^ 0xGyE
publicint getCurrentPage(){ +z4E:v
return currentPage; &`oybm-p(
} TV=K3F5)M
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/** ocu,qL)W
* @param currentPage 5th?m>
* The currentPage to set. [ ou$*
*/ y @S_CB47
publicvoid setCurrentPage(int currentPage){ iX[g
this.currentPage = currentPage; MU%7'J :_
} <RKT
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/** IC?(F]$%>
* @return $<yhEvv
* Returns the everyPage. .5uqc.i"f
*/ =*1NVi $n
publicint getEveryPage(){ e3ce?gk
return everyPage; `Qjs{H
} |]?zH~L
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/** \W]gy_=D{
* @param everyPage .cbC2t95
* The everyPage to set. VD<z]@
*/ 2vWn(6`
publicvoid setEveryPage(int everyPage){ Q8MIpa!:
this.everyPage = everyPage; 7Ja*T@ ! h
} ;tSAQ
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/** `BVmuUMm
* @return ]f0OmUHR5i
* Returns the hasNextPage. 1
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*/ T7%!JBg@
publicboolean getHasNextPage(){ L$BV`JWPw
return hasNextPage; Nte$cTjX
} 9z..LD(
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/** ?w+ V:D
* @param hasNextPage _ OC@J*4.
* The hasNextPage to set. BlQX$s]
*/ X8">DR&>Y
publicvoid setHasNextPage(boolean hasNextPage){ u~aRFQ:
this.hasNextPage = hasNextPage; Qz3Z_V4k9
} aL%E#
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/** i[@13kr
* @return 2j}DI"|h
* Returns the hasPrePage. 1[T7;i$
*/ [q_+s
publicboolean getHasPrePage(){ UKQ"sC
return hasPrePage; 4(8trD6
} Px&_6}YWy
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/** Zskj?+1
* @param hasPrePage >=|p30\b
* The hasPrePage to set. ;0Pv49q
*/ SI=u-'%
publicvoid setHasPrePage(boolean hasPrePage){ NB4O,w
this.hasPrePage = hasPrePage; kw@^4n+M
} ~7 U~
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/** 50j8+xJPV
* @return Returns the totalPage. r:;.?f@
* H=Ilum06
*/ KVJ,
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publicint getTotalPage(){ (Xcy/QT
return totalPage; fj))Hnt(|
} i5t6$|u:&m
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/** RGE(#
* @param totalPage zD79 M
* The totalPage to set. p*&0d@'r
*/ qS2Nk.e]o
publicvoid setTotalPage(int totalPage){ Z sTtSM\Ac
this.totalPage = totalPage;
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} 2h'Wu
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} /rnI"ze`
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上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 hU8Y&R)=9
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个PageUtil,负责对Page对象进行构造: {PcJuRTHB
java代码: U~N7\Pa4
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/*Created on 2005-4-14*/ 0{|HRiQH9+
package org.flyware.util.page; k=hWYe$iAz
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import org.apache.commons.logging.Log; iU;e!\A
import org.apache.commons.logging.LogFactory; WXl+w7jr
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/** \ph.c*c
* @author Joa >w@+cUto
* =O![>Fu5
*/ @)?]u
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publicclass PageUtil { K"H\gmV_g
);\c{QF
privatestaticfinal Log logger = LogFactory.getLog AQlB_@ b
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(PageUtil.class); FT@uZWgQ=
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/** 15\m.Ix
* Use the origin page to create a new page ^AS\a4`/
* @param page r8J 7zTD&
* @param totalRecords #Ub_m@@4
* @return hTr5Q33y>
*/ 7{L4a\JzT
publicstatic Page createPage(Page page, int 6'r8.~O
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totalRecords){ ~ELMLwn.
return createPage(page.getEveryPage(), qW0:q.
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page.getCurrentPage(), totalRecords); ]
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} aa`(2%(:
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/** a>'ez0C
* the basic page utils not including exception t'rN7.d
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handler _\}'5nmw\
* @param everyPage d,V#5l-6
* @param currentPage 4Z( #;9f
* @param totalRecords ^dHQ<L3.*
* @return page N1c=cZDV
*/ z1PwupXt1
publicstatic Page createPage(int everyPage, int <Kd(fFe
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currentPage, int totalRecords){ V&M*,#(?
everyPage = getEveryPage(everyPage); }}JMwT
currentPage = getCurrentPage(currentPage); =?<WCR
C*
int beginIndex = getBeginIndex(everyPage, QF#w$%7
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currentPage); BBB@M
int totalPage = getTotalPage(everyPage, vk&
gR
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totalRecords); /\I6j;$z
boolean hasNextPage = hasNextPage(currentPage, G*fo9eu5$
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totalPage); z)qYW6o%
boolean hasPrePage = hasPrePage(currentPage); /kW Z 8Z
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returnnew Page(hasPrePage, hasNextPage, $KiCs]I+
everyPage, totalPage, Oj5UG*
currentPage, &O&HczO
0
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beginIndex); Ts5)r(
} XA>W>|
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privatestaticint getEveryPage(int everyPage){ 1i76u!{U
return everyPage == 0 ? 10 : everyPage; ,=:K&5mCv
} ]pax,|+$C
ef5)z}B
privatestaticint getCurrentPage(int currentPage){ y_Y(Xx3
return currentPage == 0 ? 1 : currentPage; :Ha/^cC/3
} &L;ocd$
:C~Ar]
privatestaticint getBeginIndex(int everyPage, int Ott6y
5)k8(kH
currentPage){ uN|A}/hr]
return(currentPage - 1) * everyPage; _R4}\3}!
} 9%!h/m>rW
[GLH8R
privatestaticint getTotalPage(int everyPage, int BG>Y[u\N
"yn~axk7
totalRecords){ ;H_/o+
int totalPage = 0; Dyov}y
RLmOg{L
if(totalRecords % everyPage == 0) WE<?y_0y&
totalPage = totalRecords / everyPage; N9e'jM>Oos
else "TV'}HH
totalPage = totalRecords / everyPage + 1 ; ejROJXB
ALF0d|>=uj
return totalPage; /WrB>w
} f98,2I(>`+
|3*9+4]a
privatestaticboolean hasPrePage(int currentPage){ jjs/6sSRk
return currentPage == 1 ? false : true; sVLvnX,
} m|a9T#B(
=kjKK
privatestaticboolean hasNextPage(int currentPage, C"{^wy{sL
aAo|3KCs
int totalPage){ WJShN~ E
return currentPage == totalPage || totalPage == Y[
G_OoU
]K=#>rZrB
0 ? false : true; ( ;FxKm<P@
} Pf*6/7S:
b/SBQ"B%
jk AjYR .
} zTz}H*U
`c`VIq?
Ma YU%h0
`zd,^.i5~
vCzZjGBY
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。 *FS8]!Qg
`KJ(. m
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 fqNh\~kja
( xs'D4
做法如下: -9Q(3$}
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 Lkt4F
LU1I
`E
的信息,和一个结果集List: h<9s&
p
java代码: jUe@xis<T
o2/:e
s\*L5{kiSl
/*Created on 2005-6-13*/ 4>JSZ6i#n
package com.adt.bo; KkvcZs'4m
L4By5)
import java.util.List; o3J#hQrl
dbp\tWaW
import org.flyware.util.page.Page; :6n#y-9^1
xQoZ[
/** u?osX;'w
* @author Joa L\:|95Yq
*/ VUb>{&F[
publicclass Result { q6zVu(
7CIN!vrC|1
private Page page; /x VHd
%xt9k9=vZ
private List content; "TZq")-
(lk9](;L
/** TCr4-"`r-{
* The default constructor ^Hd[+vAvR
*/ ]a $6QS
public Result(){ j\2Qe%d
super(); SSK}'LQ
} ?=u?u
k<-
)M0YX?5AR
/** r`H}f#.KR
* The constructor using fields agIqca;
* DUp`zW;B
* @param page wk(25(1q
* @param content 8-Abg:)
*/ |/Nh#
public Result(Page page, List content){ |'^s3i&w
this.page = page; 1\}vU
this.content = content; _`$Q6!Z)l
} A*JOp8\)
/{T&l*'
/** iaGA9l<b
* @return Returns the content. j=WxtMS
*/ K-qWT7<
publicList getContent(){ u]^s2v
return content; qeZG/\,
} l:HQ@FX
.OPknC
/** rRTKF0+
* @return Returns the page. |IgR1kp+.
*/ Xp<q`w0I,
public Page getPage(){ &@~K8*tmK
return page; -amo8V;2H
} ^y<^hKjV
,d"T2Hy
/** &<&tdShI
* @param content jqUVERbc
* The content to set. i~@gI5[k+
*/ ^e:z ul{;]
public void setContent(List content){ }:m#}s
this.content = content; l6M?[
} m=l>8
uGU2
/** 0.MB;gm:
* @param page <)qa{,GX\
* The page to set. <=(K'eqC^
*/ 7 N}@zPAZ
publicvoid setPage(Page page){ 7Cz~nin>7
this.page = page; 26V6Y2X
} T(!1\ TB
} *zrT;jG
6pt,]FlU
.K
C*
(}-
O=K
lc+Oo
TWP@\ BQ
2. 编写业务逻辑接口,并实现它(UserManager, >AEp\*
WQ|Ufl;
UserManagerImpl) $^x=i;>aK.
java代码: \!ZA#7
/b+~BvTh
7nt(Rtbsu
/*Created on 2005-7-15*/ I|X`9
package com.adt.service; mnt&!X4<
b(Y
import net.sf.hibernate.HibernateException; 9z,sn#-t
O4rjGTRF
import org.flyware.util.page.Page; H_xHoCLI
c <TEA
import com.adt.bo.Result; g#S
X$k-O
E|=x+M1sH
/** j{C~wy!J
* @author Joa >+O0W)g{o
*/ 6IqPZ{g9K'
publicinterface UserManager { u`ir(JIj]
8mX!mYO3c
public Result listUser(Page page)throws +3,7 Apj
KOixFn1
HibernateException; 7%h;To-<6
2> a&m>
} ,xwiJfG;
]
\kE0h\
fTxd8an{
FB k7Cn!
Q%CrB>|@
java代码: Q Xd`P4a
}T_"Vg q
W ?x~"-*
/*Created on 2005-7-15*/ fh#:j[R4e
package com.adt.service.impl; #JUh"8N'
Tv%7=P;r
import java.util.List; T{prCM
:3F[!y3b
import net.sf.hibernate.HibernateException; ^EIuGz1@0
0fc;H}B*
import org.flyware.util.page.Page; xI,3(A.
import org.flyware.util.page.PageUtil; @!;A^<{ka
0f4 y"9m
import com.adt.bo.Result; oc?|"
import com.adt.dao.UserDAO; 2)EqqX[D
import com.adt.exception.ObjectNotFoundException; 73qE!(
import com.adt.service.UserManager; |5>Tf6$(
g?
vz\_
/** 2j
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* @author Joa ;CO qu#(
*/ 6 ;'s9s"
publicclass UserManagerImpl implements UserManager { 4KH'S'eR
:EW1I>}_
private UserDAO userDAO; RFM;?!S
A6z2KVk
/** S{llpp{E
* @param userDAO The userDAO to set. UVDMYA0
*/ + 149 o2
publicvoid setUserDAO(UserDAO userDAO){ 8Hq4ppC
this.userDAO = userDAO; p3_
Qx
} y,?=,x}o#
vhMoCLb
/* (non-Javadoc) nscnG5'{+
* @see com.adt.service.UserManager#listUser 8{Wl
+B{u,xgg
(org.flyware.util.page.Page) ybpOk
*/ )[eTZg
public Result listUser(Page page)throws 2UQF:R?LQ
Zx8$M5
HibernateException, ObjectNotFoundException { iKq_s5|sW
int totalRecords = userDAO.getUserCount(); (ot,CpI(I
if(totalRecords == 0) D)MFii1J~
throw new ObjectNotFoundException (jKqwVs.:
Az8b_:=
("userNotExist"); cO:lpsKYQ
page = PageUtil.createPage(page, totalRecords); ;9~YQW@|
List users = userDAO.getUserByPage(page); IAA_Ft
returnnew Result(page, users); F]RPM(!5O)
} tk0m[HN@eV
x,: k/]
} Ztk%uc8_lM
c,#=In2
eNfH9l2k
oW
OR7)?r
!I|_vJ@<
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 I484cR2.
5VE=Oo#&
询,接下来编写UserDAO的代码: +:Xg7H*
3. UserDAO 和 UserDAOImpl: FM%WMyb[
java代码: ^/%o
I;O{
wsdZwik
'*[7O2\%/
/*Created on 2005-7-15*/ 5NkF_&S_1
package com.adt.dao; eP (*.
Uhu?G0>O
import java.util.List; 8K^#$,.."
AK
lra$
import org.flyware.util.page.Page; Z/Wf
Wrbv<8}%c
import net.sf.hibernate.HibernateException; ke@OG! M /
ZKW1HL ]m
/** ys!O"=OJ
* @author Joa J+CGhk
*/ N9ipw r'P
publicinterface UserDAO extends BaseDAO { 8-gl$h
lB2F09`
publicList getUserByName(String name)throws 6r^ZMW
o>*`wv
HibernateException; ,or;8aYc#
[-`s`g-
publicint getUserCount()throws HibernateException; ZYB5s~;eB"
Gy+c/gK
publicList getUserByPage(Page page)throws f2tCB1[D+
+% <kcc3
HibernateException; ZK?V{X{";
nls$
wE
} *QNX?8Fm_
.`*;AT
`C7pM
H.hKh
"#36-
java代码: ` *hTx|!'
ZC$u8$+P
n[BYBg1yG
/*Created on 2005-7-15*/ {Mo[C%
package com.adt.dao.impl; uD{^1c3x
CVY-U|xFY
import java.util.List; D,$M$f1
GQ85ykky
import org.flyware.util.page.Page; EId>%0s5
?AO=)XV2
import net.sf.hibernate.HibernateException; >q')%j
import net.sf.hibernate.Query; ys)
X'.lh#&
import com.adt.dao.UserDAO; qi^kf
3f>9tUWhTy
/** -5os0G80
* @author Joa Ur[ai6LNG
*/ (^T}6t3+4
public class UserDAOImpl extends BaseDAOHibernateImpl d:Z|It
cEXd#TlY~X
implements UserDAO { 1C=42ZZ&2
^^V+0 l
/* (non-Javadoc) zWN]#W`
* @see com.adt.dao.UserDAO#getUserByName 0LGHSDb
X+;#^A3
(java.lang.String) l d%#.~Q
*/
aR)UHxvX
publicList getUserByName(String name)throws M~X~2`fFH
l"&iSq!3=
HibernateException { e\#aQ1?"
String querySentence = "FROM user in class e2xKo1?I
)-6>!6hZ
com.adt.po.User WHERE user.name=:name"; SXXO#
Query query = getSession().createQuery 'D[ *|Qcy
XThU+s9
(querySentence); Us6~7L00
query.setParameter("name", name); *Qngx
return query.list(); %YuFw|wO
} Ug[0l)
[ P*L`F
/* (non-Javadoc) 1JS5 LS
* @see com.adt.dao.UserDAO#getUserCount() G=Xas"|
*/ 5a5JOl$8
publicint getUserCount()throws HibernateException { eHHU2^I,
int count = 0; <e|B7<.
String querySentence = "SELECT count(*) FROM < A`srmS?
)):D&wlq
user in class com.adt.po.User"; ()Img.TIt
Query query = getSession().createQuery .<K9Zyi
p:|7d\r
(querySentence); F(U(b_DPM
count = ((Integer)query.iterate().next 3ug>,1:6-
2_6@&2
()).intValue(); sld cI@Z
return count; f'j<v
} ?Rh[S
M(} T\R
/* (non-Javadoc) + >tSO!}[
* @see com.adt.dao.UserDAO#getUserByPage ,]@Sytky
t,~feW,
(org.flyware.util.page.Page) 7&dF=/:X@
*/ YyY?<<z%
publicList getUserByPage(Page page)throws 47&p*=
| m#"
HibernateException { uE#"wm'J
String querySentence = "FROM user in class N]I::
Vvn~G.&)
com.adt.po.User"; <UW-fI)X
Query query = getSession().createQuery ~:b5UIAk
CT.hBz
-S
(querySentence); o3'Za'N.
query.setFirstResult(page.getBeginIndex()) }dq)d.c
.setMaxResults(page.getEveryPage()); Q2gz\N
return query.list();
/p|L.&`U
} BI>r'
L>`inrpz=w
} q) e*eN
:dlG:=.W
BE!WCDg,
=1VpO{q
TaG(sRI
至此,一个完整的分页程序完成。前台的只需要调用 |pT[ZT|}G
@ +>>TGC
userManager.listUser(page)即可得到一个Page对象和结果集对象 nI`9|W
5N#Sic M
的综合体,而传入的参数page对象则可以由前台传入,如果用 (]"`>,ray
vf!lhV-UG+
webwork,甚至可以直接在配置文件中指定。 YQ-V^e6
S2V+%Z
_J
下面给出一个webwork调用示例: *Fd(
java代码: ZjgfkZAS
YB9)v5Nz(
K
&G
/*Created on 2005-6-17*/ #!jwn^yq
package com.adt.action.user; a/~1CrYr
_ o6Zj1p
import java.util.List; ib(4Y%U6~
aslb^
import org.apache.commons.logging.Log; ~kZ?e1H
import org.apache.commons.logging.LogFactory; e$-Y>Dd
import org.flyware.util.page.Page; c*V/2"
5
Q/l388'
import com.adt.bo.Result; 0fw>/"v
import com.adt.service.UserService; Zx|VOl,;
import com.opensymphony.xwork.Action; E7U.>8C
xQs._YY
/** WQNFHRfO*n
* @author Joa zE=^}K+
*/ h(FFG%H(
publicclass ListUser implementsAction{ j-/F*P
j[$+hh3:
privatestaticfinal Log logger = LogFactory.getLog RAoY`AWI
q:P44`Aq
(ListUser.class); XNkZ^3mq
.#Lu/w' -M
private UserService userService; B|kIiL63
D
q!) nSD
private Page page; A{wSO./3
&bwI7cO
privateList users; eq4Yc*|9
M^y5 Dep
/* 1v9#Fr Y
* (non-Javadoc) GOY!()F
* 4#D>]AX
* @see com.opensymphony.xwork.Action#execute() Z7=k$e
*/ |EP=<-|
publicString execute()throwsException{ QqB9I-_
Result result = userService.listUser(page); !@f!4n.e|I
page = result.getPage(); M~*o =t
users = result.getContent(); . L]!*
return SUCCESS; L@~0`z:>iP
} #D Oui]
M~djX} #\
/** jGKI|v4U(
* @return Returns the page. ,Y27uey{wa
*/ joJQ?lG
public Page getPage(){ Ft 2u&Rtx
return page; C<q@C!A
} (x8D ]a
$&FeR*$|g
/** @l&>C#K\
* @return Returns the users. hR~~k~84
*/ -Z&9pI(3R~
publicList getUsers(){ ^r^) &]
return users; O`'r:W
} 1y6{3AZm<
5H/D~hr&
/** 3/RNStd<L!
* @param page ),U>AiF]
* The page to set. $w
,^q+
*/ kSU]~x
publicvoid setPage(Page page){ '>dx~v %
this.page = page; fqD1Ej
} JX2@i8[~
u|M_O5^
/** ivP#qM1*;
* @param users j#
!U6T
* The users to set. oTxE]a,
*/ e'5sT#T9 l
publicvoid setUsers(List users){ \t%rIr
this.users = users; 5VK.Zs\
} 6 9EdMuf
)\fLS d
/** P~ODd(
* @param userService ,(Nr_K
* The userService to set. qBcwM=R3P
*/ U<.,"`=l
publicvoid setUserService(UserService userService){ $g]'$PB
this.userService = userService; ])$Rw$`w
} %j2ZQ/z
} uxD$dd?
Zf8_ko;|:-
N Uo
SR*KZ1U
vjO@"2YEw
上面的代码似乎看不出什么地方设置了page的相关初值,事实上, 5YnTGf&
Ce!xa\
可以通过配置文件来进行配置,例如,我想每页显示10条记录,那 '(yjq<
05/'qf7P,U
么只需要: E@92hB4D"
java代码: :6y;U
Gq9pJ
I?Ct@yxhF'
<?xml version="1.0"?> "/qm,$
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork I2<5#|CXpZ
>sm<$'vZ/
1.0//EN" "http://www.opensymphony.com/xwork/xwork- -)$5[jM]
)~H&YINhn
1.0.dtd"> #Bi8>S
xHi.N*~D
<xwork> m}o4Vr;"
&u~#bDh
<package name="user" extends="webwork- (|.rEaTA[1
"vN~7%
interceptors"> hYEUiQ
.GOF0puiM
<!-- The default interceptor stack name Z<@dM2b)
/{*0
\`;
--> Eao^/MKx-
<default-interceptor-ref [7@9wa1v!
bz\-%$^k
name="myDefaultWebStack"/> 1CpIK$/
kNrN72qg
<action name="listUser" s>1Wjz2M
IH$ZPux
class="com.adt.action.user.ListUser"> qB8R4wCf
<param F<LRo}j"9Q
#Zt(g( T
name="page.everyPage">10</param> B"=w9w]
<result XCUU(H
^QTtCt^:
name="success">/user/user_list.jsp</result> TIYo&?Z)
</action> ]@9ZUtU,;N
0mi$_Ld+
</package> o2e gNTG
b_rHt
s
</xwork> v2;'F
: XaBCF*
b&\f 8xZ
{'$+?V"&
rs+
["h
(~OP)F).
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 n>\2_$uDI
O6Mxp-
了。并可以通过随意修改配置文件来修改每页需要显示的记录数。 o#=@!m
t)4AQ
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 vj hh4$k
}`^DO
Ar
"z9 p(|oZ
#[ ?E,
y';"tD Fb
我写的一个用于分页的类,用了泛型了,hoho K4K]oT
W 2T6JFv
java代码: c=#V*<
:oO
?A
"1|\V.>>;
package com.intokr.util; O"V;otlC
nC(<eL
import java.util.List; =]m,7 v Rq
b>x03%
/** R8C#DB
* 用于分页的类<br> ()o[(Hx+ph
* 可以用于传递查询的结果也可以用于传送查询的参数<br> z6x`O-\
* gOLN7K-)
* @version 0.01 &"'Z)iWm
* @author cheng uN+]q qCf
*/ "^NsbA+
public class Paginator<E> { 4I!g?Moh
privateint count = 0; // 总记录数 Z)'gj
privateint p = 1; // 页编号 w:c9Z=KX
privateint num = 20; // 每页的记录数 Z,1b$:+
privateList<E> results = null; // 结果 ~>B`T%=H
r}i}4K[1
/** 45.Vr[FS.
* 结果总数 8~ wP?
*/ pxb4x#CC
publicint getCount(){ 8KMo !p\i
return count; t+Au6/Dx?
} KGJ *h
_:7:ixN[Ie
publicvoid setCount(int count){ kY^ k*-v
this.count = count; "X,*VQl:
} /_qW?LKG/
W*r1Sy
/** p-XO4Pc6
* 本结果所在的页码,从1开始 L25%KGg'o
* )18C(V-x
* @return Returns the pageNo. 6<mlx'
*/ [ahK+J
publicint getP(){ M2pFXU?]
return p; Nk;ywC"e;
} C2C1 @=w
9:,ZG4s
/** 3*= _vl3
* if(p<=0) p=1 nZ %%{#T7
* 5jAS1XG
* @param p %00cC~}4
*/ i|[**P
publicvoid setP(int p){ 3@42uG>
if(p <= 0) J#xZ.6)
p = 1; y;<F|zIm
this.p = p; K$I`&M(
} XNJ3.w:R
Zygu/M6
/** 6uIgyO*;k
* 每页记录数量 +E-CsNAZ*"
*/ $:RR1.Tv
publicint getNum(){ :}z`4S@b
return num; JFFluL=-
} >Og| *g
nzU;Bi^m
/** xauMF~*
* if(num<1) num=1 =SD^Jl{H
*/ ;zT3Fv\
publicvoid setNum(int num){ NG_7jZzXA9
if(num < 1) b|e1HCH
num = 1; 9,[AfI
this.num = num; |y
pXO3
} <$??Z;6
7n,=`0{r
/** Y_)xytJ$
* 获得总页数 -2'1KAk-W
*/ q_cP<2`@V
publicint getPageNum(){ 1my1m
return(count - 1) / num + 1; 8SA"
bH:
} +o?;7
n8tw8o%&[
/** 9yz@hdG
* 获得本页的开始编号,为 (p-1)*num+1 %n6NVi_[
*/ !e:_$$j
publicint getStart(){ Qk >9o
return(p - 1) * num + 1; Vh?RlIUA
} vXm'ARj
ne:
'aq
/** vi28u xc
* @return Returns the results. +)LCYDRV7
*/ }U '
publicList<E> getResults(){ [&g"Z"
return results; ,0c]/Sd*p
} pu5%$}dBE
IhRdn1&
public void setResults(List<E> results){ ;;6$d{
this.results = results; (D:-p:q.
} 6j!idA!'
udXzsY9Ng
public String toString(){ D?=4'"@v
StringBuilder buff = new StringBuilder W-*HAS
nxB[To*P
(); zz!jt
A
buff.append("{"); *d`KD64
buff.append("count:").append(count); D5!#c-Y-
buff.append(",p:").append(p); 1_};!5$.
buff.append(",nump:").append(num); 1tLEKSo+
buff.append(",results:").append #0PZa$kM(o
n
=WH=:&
(results); E]v?:!!ds
buff.append("}"); \~g,;>%7Y
return buff.toString(); 'iTY?
} c8Q}m(bhWI
!9.FI{W
} Ii&p v
Q :.i[
OE}FZCXF