Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 !~fy".|x
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 'tn-o
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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 <RJ+f-
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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 /j"aOLL|
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分页支持类: Y[.f`Ei2
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java代码: bA02)?L
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package com.javaeye.common.util; NEW0dF&)
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import java.util.List; ,iMdv+
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publicclass PaginationSupport { h{VdW}g
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publicfinalstaticint PAGESIZE = 30; Rv Uw,=
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privateint pageSize = PAGESIZE; gPcOm
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privateList items; vpz l{
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privateint totalCount; ~*hCTqHvN
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privateint[] indexes = newint[0]; ;YYnIb(
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privateint startIndex = 0; 0`$fs.4c
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public PaginationSupport(List items, int q]#j,}cN9
LX{mr{
totalCount){ uxbLoE
setPageSize(PAGESIZE); 9=.7[-6i9
setTotalCount(totalCount); }.r)
setItems(items); dfWtLY
setStartIndex(0); Rh%C$d(
} n*r Xj{Kt
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public PaginationSupport(List items, int (N?nOOQ
*X8Pa;x
totalCount, int startIndex){ EL(BXJrx{
setPageSize(PAGESIZE); .\mkgAlyaM
setTotalCount(totalCount); I|.
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setItems(items); Xh@;4n
setStartIndex(startIndex); IubzHf
} b]g#mQ
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public PaginationSupport(List items, int `Ln1g@
p
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totalCount, int pageSize, int startIndex){ cS(=wC
setPageSize(pageSize); ?D['>Rzu
setTotalCount(totalCount); @nOuFX4
setItems(items); 2[i(XG{/
setStartIndex(startIndex); (&Mv!6]
} K)GpQ|4:<
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publicList getItems(){ EAV6qW\r5]
return items;
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} p<c1$O*
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publicvoid setItems(List items){ &Xh=bM'/%m
this.items = items; uTNy{RBD+
} aj]pN,g@N
KN'twPFq
publicint getPageSize(){ \|6Q]3l
return pageSize; K6s tkDhb
} 8^!ib/@v"
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publicvoid setPageSize(int pageSize){ py$i{v%
this.pageSize = pageSize; emI F{oP
} 6\USeZh
@?5pY^>DK
publicint getTotalCount(){ 11RqP:zg
return totalCount; L'O=;C"f
} zICAV -&
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publicvoid setTotalCount(int totalCount){ 6W9lKD_i
if(totalCount > 0){ /$^SiE+N
this.totalCount = totalCount; ]l^"A~va
int count = totalCount / zqxN/H]z
<SiJA`(7
pageSize; Lw`}o` D
if(totalCount % pageSize > 0) *1h@Jb34
count++; 0u
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indexes = newint[count]; SK5__Ix
for(int i = 0; i < count; i++){ # blh9.V&F
indexes = pageSize * `$ pJ2S
@ 1FWBH~
i; jQ['f\R
} [nLd> 2P
}else{ oxLO[js
this.totalCount = 0; x LGMN)@r
} wlpcuz@
} 0s6eF+bs
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publicint[] getIndexes(){ |Elz{i-
return indexes; ^ #3,*(S
} ekd;sEO
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publicvoid setIndexes(int[] indexes){ j-v/;7s/B
this.indexes = indexes; 2{S*$K[M
} tR(L>ZG{
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publicint getStartIndex(){ c
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return startIndex; Up*6K =Tny
} V o%GO9b;
= Q"(9[Az
publicvoid setStartIndex(int startIndex){ U["IXR#
if(totalCount <= 0) j.:f=`xf
this.startIndex = 0; 64D4*GQ
elseif(startIndex >= totalCount) {6iHUK
this.startIndex = indexes n1)]. `
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[indexes.length - 1]; lHO.pN`2
elseif(startIndex < 0) m Gx{Vpt
this.startIndex = 0; 4MRN{W6
else{ 0OBwe6*
this.startIndex = indexes 1-PFM-
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[startIndex / pageSize]; AjINO}b
} OT#foP
} Pt7C/
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J7k=5Fqej;
publicint getNextIndex(){ zwK$ q=-:
int nextIndex = getStartIndex() + iOiXo6YE
<Ys7`e6eY
pageSize; ZK8DziO
if(nextIndex >= totalCount) :fQN_*B4@4
return getStartIndex(); Fl++rUT
else 4|NcWpaV7
return nextIndex; 0$|wj^?U
} *-gmWATC6
$}P>_bq
publicint getPreviousIndex(){ x5,|kJ9S
int previousIndex = getStartIndex() - j&0t!f.Rv
<<6gsKP
pageSize; L>!MEMqm
if(previousIndex < 0) 0p=
return0; >Vb V<ak
else ;(IAhWE?7
return previousIndex; \{1Vjo
} A&_v:z4y/
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} 9 'IDbe{
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抽象业务类 +Q!Kj7EU/
java代码: dq3"L!0u
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/** >k(AQW5?
* Created on 2005-7-12 @@|H8mP}H
*/ 3Ael
package com.javaeye.common.business; HK<oNr.d52
hYh~[Kr^@^
import java.io.Serializable; 6H:EBj54?
import java.util.List; >Yfo $S_
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import org.hibernate.Criteria; b<KKF '
import org.hibernate.HibernateException; ? \NT'CG
import org.hibernate.Session; {>l`P{{y
import org.hibernate.criterion.DetachedCriteria; j{P3o<l&`
import org.hibernate.criterion.Projections; 0vM,2:kf*
import X($@E!|
!}HT&N8[r
org.springframework.orm.hibernate3.HibernateCallback; (ce"ED`1
import v9Ez0 :)
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org.springframework.orm.hibernate3.support.HibernateDaoS 'Y5=A!*@tf
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upport; BF]+fs`
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import com.javaeye.common.util.PaginationSupport; G_?qY#"(
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public abstract class AbstractManager extends vo2 T P:
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HibernateDaoSupport { JDB Ni+t
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privateboolean cacheQueries = false; *1_A$14l
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privateString queryCacheRegion;
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publicvoid setCacheQueries(boolean y#5;wb<1
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cacheQueries){ eXMl3Lxf
this.cacheQueries = cacheQueries; JP 8v2)
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} mC84fss
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publicvoid setQueryCacheRegion(String k!m9
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queryCacheRegion){ vC5y]1QDd
this.queryCacheRegion = CB?,[#r5f
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queryCacheRegion; b=Y3O
} )nUTux0K\
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publicvoid save(finalObject entity){ U`ELd:
getHibernateTemplate().save(entity); NGb\e5?
} _xU2C<)1&
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publicvoid persist(finalObject entity){ z>W'Ra6
getHibernateTemplate().save(entity); xr-v"-
} j es[a
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publicvoid update(finalObject entity){ ?:sQ]S/Er
getHibernateTemplate().update(entity); ^ZO3:"t!w
} 1(WNrVm;
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publicvoid delete(finalObject entity){ Toc="F`SW
getHibernateTemplate().delete(entity); 3UQ~U 8
} Fv9n>%W&
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publicObject load(finalClass entity, )NS&1$
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finalSerializable id){ nD;8)VI'I
return getHibernateTemplate().load fHwr6"DJ
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(entity, id); \~'+TW
} P[C03a!lXg
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publicObject get(finalClass entity, VcR(9~
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finalSerializable id){ 4f>
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return getHibernateTemplate().get %q
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(entity, id); "+J[7p}`@
} w.\#!@kZ!
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publicList findAll(finalClass entity){ #:3~I
return getHibernateTemplate().find("from Ie8jBf -
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" + entity.getName()); '; Z!(r
} `@|Kx\y4=j
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publicList findByNamedQuery(finalString w@ =U f7
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namedQuery){ au 5qbP
return getHibernateTemplate ;p 'Ej'E
%{M&"M v
().findByNamedQuery(namedQuery); ]pP [0S
} yjxv D
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publicList findByNamedQuery(finalString query, ?_7^MP>
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finalObject parameter){ seo.1.Da2
return getHibernateTemplate Ro|%pT
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().findByNamedQuery(query, parameter); )X-/0G=N-
} :IlJQ{=W
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publicList findByNamedQuery(finalString query, ^J Y]w^u
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finalObject[] parameters){ 42mZ.,<
return getHibernateTemplate uKocEWB=/F
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().findByNamedQuery(query, parameters); ;nB.f.e`
} /DBldL7yi
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publicList find(finalString query){
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return getHibernateTemplate().find 1ti4 ZM
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(query); 1W
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} oaJnLd90W
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publicList find(finalString query, finalObject ESAFsJ$r;
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parameter){
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return getHibernateTemplate().find Xm!;
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(query, parameter); i5 F9*
} R87e"m/C%
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public PaginationSupport findPageByCriteria 9>k-";
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(final DetachedCriteria detachedCriteria){ 0QxE6>xL=
return findPageByCriteria <^(g<B`>
&.}Zj*BD
(detachedCriteria, PaginationSupport.PAGESIZE, 0); CsND:m
} .[KXO0Ui6u
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public PaginationSupport findPageByCriteria _<i*{;kR6
#U j~F
(final DetachedCriteria detachedCriteria, finalint [10;Mg
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startIndex){ 1]<wZV}.
return findPageByCriteria `vFYeN;
%"0g}tK6
(detachedCriteria, PaginationSupport.PAGESIZE, -O?}-6,_Z
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startIndex); z_LN*u
} $M=W`E[g
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public PaginationSupport findPageByCriteria V]$Tbxg
(NBq!;_2,x
(final DetachedCriteria detachedCriteria, finalint nwm1YPs%v]
(n,!v)
pageSize, 4/tp-dBip
finalint startIndex){ } QqmDK.
return(PaginationSupport)
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getHibernateTemplate().execute(new HibernateCallback(){ Y([YDn
publicObject doInHibernate 'sCj|=y2Qc
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(Session session)throws HibernateException { ZOK,P
Criteria criteria = Dqw?3 KB
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detachedCriteria.getExecutableCriteria(session); VTt{0 ~
int totalCount = QP{V
+$F_7Hx
((Integer) criteria.setProjection(Projections.rowCount ny]R,D0
U- a+LS
()).uniqueResult()).intValue(); hi30|^l-
criteria.setProjection :nHa-N3
}H4Z726
(null); Rn-RMD{dh
List items = TEK]$%2
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criteria.setFirstResult(startIndex).setMaxResults
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(pageSize).list(); LPNJuz
PaginationSupport ps = _K?{DnTb
2/c^3[ccR
new PaginationSupport(items, totalCount, pageSize, rIE
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startIndex); 1eZ759PoO
return ps; VHlN;6Qlff
} Oa'DVfw2J
}, true); ,L"1Ah
} |9F^"7Q~C
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public List findAllByCriteria(final / ao|v
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DetachedCriteria detachedCriteria){ BSGC.>$s
return(List) getHibernateTemplate yRZb_Mq9U
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().execute(new HibernateCallback(){ 5IPZ;
publicObject doInHibernate fgW>U*.ar
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(Session session)throws HibernateException { /Y>$w$S
Criteria criteria = !4(X9}a
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detachedCriteria.getExecutableCriteria(session); ]R$
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return criteria.list(); I+?9}t
} B3lP#ckh
}, true); m;S!E-W
} oA;sP'
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public int getCountByCriteria(final k-$5H~(PZ
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DetachedCriteria detachedCriteria){ /7nircXj@
Integer count = (Integer) :q.g#:1s
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getHibernateTemplate().execute(new HibernateCallback(){ ;w/|5 ;{A;
publicObject doInHibernate NT^m.o~4
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(Session session)throws HibernateException { "lFS{7
Criteria criteria = ^11y8[[
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detachedCriteria.getExecutableCriteria(session); 5ir[}I^z
return W_%p'8,
8+>r!)Q+
criteria.setProjection(Projections.rowCount |bwz
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()).uniqueResult(); O]>FNsh !
} LovVJ^TD0i
}, true); vnNX)$f
return count.intValue(); P9Yw\
} Y~P1r]piB
} {W[OjPC~F
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用户在web层构造查询条件detachedCriteria,和可选的 F ka^0
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 *?2aIz"
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PaginationSupport的实例ps。 :6
, `M,
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ps.getItems()得到已分页好的结果集 1%v!8$
ps.getIndexes()得到分页索引的数组 PJ-EQ6W
ps.getTotalCount()得到总结果数
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ps.getStartIndex()当前分页索引 KlMSkdmW
ps.getNextIndex()下一页索引 3tO=
ps.getPreviousIndex()上一页索引 k$kOp *X
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 A5UZUU^
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,尤其是上面的示例代码,让我着实觉得该对我原来的分页查询做 @O!BQ^'hk#
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一下代码重构了。 Lp|7s8?
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我把原本我的做法也提供出来供大家讨论吧: pk%%}tP<
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首先,为了实现分页查询,我封装了一个Page类: t",=]k
java代码: iI!MF1
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/*Created on 2005-4-14*/ ?06+"Z
package org.flyware.util.page; SBf8Ipe
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/** ` XvuyH
* @author Joa n=z=%T6
* Ft<6`C
*/ %4=r .9
publicclass Page { U<YP@?w
\aEarIX#*
/** imply if the page has previous page */ AHo4%
5
privateboolean hasPrePage; ?M}W;Z
jkVX>*.|oy
/** imply if the page has next page */ Y<]A5cm
privateboolean hasNextPage; w$aiVOjgT
X6T*?t3!9[
/** the number of every page */ \>DMN #
privateint everyPage; R{3?`x!fY
bAUruTn
/** the total page number */ O`;e^PhN
privateint totalPage; [Yq*DkW
Y"n$d0%
/** the number of current page */ 1edeV48{:
privateint currentPage; =tKb7:KU
z]twh&^1L
/** the begin index of the records by the current TtWE:xE
dcd9AW=
query */ +Fk]hCL
privateint beginIndex; {:63% j
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/** The default constructor */ 5x2m]u
public Page(){ N!{waPbPi
,\DSi&T
} !,(6uO%
nNEIwlj;
/** construct the page by everyPage J7RO*.O&Iq
* @param everyPage ![ce=9@t<
* */ [X\<C '<
public Page(int everyPage){ ~+~^c|
this.everyPage = everyPage; f\|R<3 L
} f4[Bj{F
4Odf6v,*@
/** The whole constructor */ %>mB"Y,
public Page(boolean hasPrePage, boolean hasNextPage, [PhT
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3d>3f3D8;
int everyPage, int totalPage, e8Y;~OAj[
int currentPage, int beginIndex){ <hv {,1p-r
this.hasPrePage = hasPrePage; aANzL
this.hasNextPage = hasNextPage; !&f>,?wlP
this.everyPage = everyPage; (2l?~CaK
this.totalPage = totalPage; KE_GC ;bQ
this.currentPage = currentPage; -Wt(t2
this.beginIndex = beginIndex; ?xT ^9
} C)RJjaOr
ds#om2)
/** 9i?Q=Vuc~<
* @return 6p}dl>T_y
* Returns the beginIndex. .szc-r{
*/ <CIy|&J6
publicint getBeginIndex(){ k^:+Pp
return beginIndex; &~
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} &$x1^
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/** ,WKWin
* @param beginIndex 9EU0R
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* The beginIndex to set. Z{ AF8r
*/ "Xz [|Xl
publicvoid setBeginIndex(int beginIndex){ b-"kclK
this.beginIndex = beginIndex; mR1|8H!f
} EqjaD/6Y`
3m]8>1e1"
/** ? JliKFD%
* @return .*,W%r?1n6
* Returns the currentPage. *$Tz g!/
*/ .271at#-
publicint getCurrentPage(){ ro8c-[V
return currentPage; ;&~9k?v7L
} ,mY3oyu
rF:l+I]
/** <AN=@`+
* @param currentPage $;Nw_S@
* The currentPage to set. +DR,&;
*/ _C&XwCIm
publicvoid setCurrentPage(int currentPage){ r1R\cor
this.currentPage = currentPage; tT`{xM
} D3.$Vl,.
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/** 7+c}D>/`:
* @return EjjW%"C,
* Returns the everyPage. 1(4}rB3
*/ :vWixgLg
publicint getEveryPage(){ |jw{7\+
return everyPage; p8bAz
} |3K]>Lio
-q")qNt.
/** 1!"iN~
* @param everyPage _2Hehw
* The everyPage to set. xC^| S0B
*/ ;]A:(HSZj
publicvoid setEveryPage(int everyPage){ k>W}9^ cK
this.everyPage = everyPage; & Do|Hw
} #}8 x
[`/d$V!e
/** %;-r->
* @return L`@)*x)~R
* Returns the hasNextPage. e00s*LdC
*/ 1_MaaA;ow"
publicboolean getHasNextPage(){ ps&p|
return hasNextPage; *;!p#qL
} @S#Ls="G
K=Y{iHn
/** 9|5>?'CqP
* @param hasNextPage *If]f0?%
* The hasNextPage to set. vWq/A .
*/ g( -}M`
publicvoid setHasNextPage(boolean hasNextPage){ s&Lyg>>`
this.hasNextPage = hasNextPage; w7"&\8a
} 88~lP7J
Q~#[_Upkc
/** wU(N<9
* @return _]q%H ve
* Returns the hasPrePage. =CGB}qU l0
*/ r6:c<p [c
publicboolean getHasPrePage(){ n\'@]qG)Z4
return hasPrePage; whb,2=gIE
} KsF kC=
o)SA^5
/** S<=|i
* @param hasPrePage /}&@1
* The hasPrePage to set. oV,lEXz
*/ #1VejeTi
publicvoid setHasPrePage(boolean hasPrePage){ jB -wJNP/
this.hasPrePage = hasPrePage; oaMh5FPy
} kXY p.IVA
;UoXj+Z
/** F?.J1]
* @return Returns the totalPage. OJTEvb6nPg
* q%\rj?U_
*/ jdW#;
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publicint getTotalPage(){ yr,Oq~e
return totalPage; ^/_1y[j
} .In8!hjYy4
<h[l)-86
/** u(b Pdf@kz
* @param totalPage r>.^4Z@
* The totalPage to set. Y&y5^nG
*/ 6fcn(&Qk
publicvoid setTotalPage(int totalPage){ [&H?--I
this.totalPage = totalPage; +E8}5pDt
} OYwH$5
ns;nle|m
} IP-}J$$1
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yMCd5%=M\
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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 $kCXp.#k@~
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个PageUtil,负责对Page对象进行构造: xGVL|/?8
java代码: I$vM )+v=
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/*Created on 2005-4-14*/ &bw
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package org.flyware.util.page; 9G)q U
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import org.apache.commons.logging.Log; o^b4l'&o
import org.apache.commons.logging.LogFactory; .X(*mmH
Ii4lwZnz
/** nd?R|._R
* @author Joa (%^Bp\.02!
* Lf} @v
*/ -4!i(^w[m/
publicclass PageUtil { ?Rg8u
B}A7Usm
privatestaticfinal Log logger = LogFactory.getLog Bvy(vc=UDW
q" %;),@
(PageUtil.class); "i3Q)$"S
c N^,-~U
/** 1> wt
* Use the origin page to create a new page r-SQk>Y}
* @param page '@Q
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* @param totalRecords H;nq4;^yK
* @return qGgqAF#B
*/ w+Cs=!
publicstatic Page createPage(Page page, int |e#ea~/b
a}]zwV&
totalRecords){ $YCy,Ew
return createPage(page.getEveryPage(), yg-uL48q
`fUem,$)1F
page.getCurrentPage(), totalRecords); <D!\"C
} $xU5vCwAo
KN"V(<!)~
/** _8G
* the basic page utils not including exception v4V|j<R
8LouCv(>
handler j)[
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* @param everyPage R9B !F{! 5
* @param currentPage 3"OD"
* @param totalRecords B U^3U x$
* @return page ,'69RL?-Wg
*/ !b+/zXp3I
publicstatic Page createPage(int everyPage, int L8zY?v(bG
?MhY;z`=
currentPage, int totalRecords){ |Skxa\MI
everyPage = getEveryPage(everyPage); L>qLl_.
currentPage = getCurrentPage(currentPage); 1vF^<{%v
int beginIndex = getBeginIndex(everyPage, u4kg#+H
zFtRsa5+
currentPage); c>*RQ4vE
int totalPage = getTotalPage(everyPage, @'yD(ZMAz
Y=#g_(4*
totalRecords); 4LBMhLy
boolean hasNextPage = hasNextPage(currentPage, i1#\S0jN
L*VO2YI
totalPage); B3V=;zn3
boolean hasPrePage = hasPrePage(currentPage); tE: m&
;I
%TA3o71
returnnew Page(hasPrePage, hasNextPage, fEl,jA
everyPage, totalPage, 4Fr\=TX
currentPage, fem>WPvG
~Z'3(n*9
beginIndex); -$]Tn#`Fb
} ?r,lgaw
u}7#3JfLn
privatestaticint getEveryPage(int everyPage){ ttwfWfX
return everyPage == 0 ? 10 : everyPage; IaU
} uW8LG\Z>D5
[ Yzh(a8
privatestaticint getCurrentPage(int currentPage){ coxMsDs
return currentPage == 0 ? 1 : currentPage; #.(6.Li
} J=gerdIk
lF\oEMd*
privatestaticint getBeginIndex(int everyPage, int h>6'M
bw8~p%l?
currentPage){ (Hcd{]M~
return(currentPage - 1) * everyPage; &a>fZ^Y=k
} T{iv4`'
EEaf/D/ jt
privatestaticint getTotalPage(int everyPage, int <Cvlz^K[
C#<:x!
totalRecords){ SY`
U]-h
int totalPage = 0; Ua^'KRSO
lglC1W-q
if(totalRecords % everyPage == 0) <.0-K_
totalPage = totalRecords / everyPage; %s;#epP$
else "b!EtlT9
totalPage = totalRecords / everyPage + 1 ; aIv>X@U}
@}K'Ic
return totalPage; McgTTM;E
} %r0yBK2uOp
_91g=pM
privatestaticboolean hasPrePage(int currentPage){ 8xQ5[Ov
return currentPage == 1 ? false : true; zUM;Qwl
} >5&'_
(Id]'w4
privatestaticboolean hasNextPage(int currentPage, af61!?K
ey@]B5
int totalPage){ 3%]%c6
return currentPage == totalPage || totalPage == $/aZ/O)F
xq2{0q
0 ? false : true; SSKn7`
} -,Q
!:
W27EU/+3
iw\RQ
0
} G SXe=?
+s:!\(BM
;^}gC}tq
FY [WdZDZ
uoYG@L2
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。 Cg/L/0Ak
/2K4ka<?7
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 !F*7Mif_E
O+Fu zCWj
做法如下: gRS}Y8
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 i2SR.{&
,F7W_f#
@3
的信息,和一个结果集List: bb#F2r4
java代码: hHsCr@i
0*MY4r|-
V]cD^Fqp
/*Created on 2005-6-13*/ bwG2=
package com.adt.bo; %nQii?1`i
$DZ\61
import java.util.List; 2r2qZ#I}
Z5re Fok
import org.flyware.util.page.Page; NDW6UFd>1
wfQ6J0
/** D9M<>Xz)
* @author Joa #5xK&qA
*/ Y
'&&1R
publicclass Result { ~6z<tyD^
{OP[Rrm
private Page page; sas}k7m"
7*8R:X+^r
private List content; m$ZPQ0X
@UCGsw
/** gwDQ@
* The default constructor TT3GFP
*/ \kU0D
public Result(){ aA?Uf~ "t
super(); &FF%VUfQJ
} 96UL](l(`
")MjR1p
/** >4>!zZ
* The constructor using fields ld8 E!t[
* S>isWte
* @param page iB;EV8E
* @param content o(GXv3L
*/ p]/HZS.-b
public Result(Page page, List content){ m?DI]sIv#
this.page = page; f 4CS
this.content = content; 1'or[Os3=
} {.=089`{
#~l(t_m{
/** ~Ts^z(v~D2
* @return Returns the content. vt@5Hb)
*/ n $RhD93
publicList getContent(){ qjQR0MC
return content; 1zwk0={x-%
} q}[g/%
W($}G_j[B1
/** 4RCD<7
* @return Returns the page. SJb+:L>
*/ (- `h8M
public Page getPage(){ A)9OkLrc
return page; o!W
71
} ol QT r
2Wwzcvs@
/** @v^;,cu'8
* @param content -`nQa$N-
* The content to set. xE.K
*/ NUBf>~_}
public void setContent(List content){ -j1?lY
this.content = content; Vmq:As^a
} l"70|~
w U".^
+
/**
q1!45a
* @param page #-5.G>8
* The page to set. W^{zlg
*/ !nh7<VJ
publicvoid setPage(Page page){ )Il)
H
this.page = page; 28,Hd!{
}
2P3,\L
} [B<htD&
0c6b_%Rd
KE>|,Ur
I`k%/ei38
WzD=Ol
2. 编写业务逻辑接口,并实现它(UserManager, 1iNq|~
Qh*"B
UserManagerImpl) En01LrC?
java代码: MIa#\tJj
{k
BHZ$/
T<:mG%Is
/*Created on 2005-7-15*/ 7A6Qrfw
package com.adt.service; (QS4<J"
8t)5b.PS
import net.sf.hibernate.HibernateException; wq K:=
L=g(w$H
import org.flyware.util.page.Page; W:5uoO]=<
HRQ3v`P.
import com.adt.bo.Result; G8bc\]
{}gx;v)
/** 'W'['TV
* @author Joa 9)P-<
*/ Qy0Zj$,Z
publicinterface UserManager { u={A4A#
\!`k:lusa
public Result listUser(Page page)throws =CBY_
MZJ@qIg[Y
HibernateException; v_U+wga
i2bkgyzB.
} 'uy\vR&Pz
?2d! ^!9
ZC7ZlL_
i|N%dl+T=
!*I0}I
~
java代码: hIBW$
4~8!3JH39
+\s32o
zg
/*Created on 2005-7-15*/ <!qN<#$y
package com.adt.service.impl; PMOyZ3
YCBp]xuE
import java.util.List; {3)^$F=T
LIah'6qR
import net.sf.hibernate.HibernateException; ;@5N
h7?uM^p
import org.flyware.util.page.Page; p. %lE!v
import org.flyware.util.page.PageUtil; %Z.!T
z4!Y9
import com.adt.bo.Result; FaA'%P@
import com.adt.dao.UserDAO; n]nb+_-97
import com.adt.exception.ObjectNotFoundException; Z'Uc}M'U
import com.adt.service.UserManager; Fu%D2%V$/
i!yu%>:M
/** VbU*&{j
* @author Joa @#u'z~a)
*/ :`Sd5b>
publicclass UserManagerImpl implements UserManager { +HAd=DU
[]L
yu
private UserDAO userDAO; QmiS/`AAv
XEX-NE"]
/** QV%,s!_b
* @param userDAO The userDAO to set. 1r:i'cWh
*/ Q[6<Y,}(pd
publicvoid setUserDAO(UserDAO userDAO){
5~!&x@
this.userDAO = userDAO; 7my7|s[
} Ung K9uB~
~;AJB
/* (non-Javadoc) v)c[-:"z
* @see com.adt.service.UserManager#listUser ]ykMh
=w,cdU*
(org.flyware.util.page.Page) $ca>bX]
*/ Id}@
public Result listUser(Page page)throws 6+.8nx:9X
paYvYK-K?
HibernateException, ObjectNotFoundException { WHk rd8
int totalRecords = userDAO.getUserCount(); w~a_FGYX
if(totalRecords == 0) iJaA&z5sr
throw new ObjectNotFoundException n/
m7+=]v
7eU|iDYo
("userNotExist"); ^630%YO
page = PageUtil.createPage(page, totalRecords); (?ofL|Cg(
List users = userDAO.getUserByPage(page); e$Npo<u
returnnew Result(page, users); vyhxS .[9
} 9{-
Sa
6\5"36&/rQ
} $`'%1;y@
Ld4Jp`Zg
b%_[\((
+Rq7m]
"k>;K,:
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 X/AA8QV o
C<B1zgX
询,接下来编写UserDAO的代码: |M$ESj4@
3. UserDAO 和 UserDAOImpl: w+Oo-AGNH
java代码: {8im{]8_
@C"w
1}
;p8,=w
/*Created on 2005-7-15*/ ~i5t1
package com.adt.dao; =N?K)QD`
;n2b$MB?nM
import java.util.List; tj<0q<is
p+.{"%
import org.flyware.util.page.Page; 6>e YG<y{
\!J9|
import net.sf.hibernate.HibernateException; F#>^S9Gml
6v(;dolBIw
/** >sZ207*
* @author Joa sqjv3=}
*/ ,0fYB*jk
publicinterface UserDAO extends BaseDAO { :/6gGU>pu
dt1,!sHn
publicList getUserByName(String name)throws )K>2
yS";
q
HibernateException; |)pgUI2O[
"v[?`<53^l
publicint getUserCount()throws HibernateException; fs3jPHZJ#
}DzN-g<K
publicList getUserByPage(Page page)throws 1 GB
\EC7*a0
HibernateException; ;sZHE&+
mEVne.D
} Q"D%xY
R)u ${
>=!$(JgX
bA*T1Db,t>
3`^NaQ
java代码: QVJvuiUh
f%ynod8
<f/wWu}
/*Created on 2005-7-15*/ n%%u0a%
package com.adt.dao.impl; FZJyqqA$_
38 HnW
import java.util.List; qE)G;Y<,1
<CM}g4Y
import org.flyware.util.page.Page; <cx,Z5W
.:?cU#.
import net.sf.hibernate.HibernateException; $/XR/
import net.sf.hibernate.Query; rxM)SC;P
99mo]1_
import com.adt.dao.UserDAO; @uzzyp r>
]>'yt #]
/** 3!<} -sW4
* @author Joa EC0M0qQ
*/ u4,b%h.
public class UserDAOImpl extends BaseDAOHibernateImpl "YQ%j+
^{(i;IVG
implements UserDAO { 5^GFN*poig
VQ]MJjvb
/* (non-Javadoc) .0H!B#9
* @see com.adt.dao.UserDAO#getUserByName F)Qj<6
,`nl";Zc
(java.lang.String) O,A}p:Pgs
*/ l0g`;BI_
publicList getUserByName(String name)throws Da WzQe=
Q{))+'s2h
HibernateException { 'h~I#S4!
String querySentence = "FROM user in class 8~s-@3J
AcCM
W@e
com.adt.po.User WHERE user.name=:name"; B$kp\yL
Query query = getSession().createQuery x|oa"l^JZ"
9'S~zG%{
(querySentence); r")zR,
query.setParameter("name", name); 2xJT!lN
return query.list(); ~!G&K`u
} $h|rd+},
8G0DuMI5
/* (non-Javadoc) TR([u
* @see com.adt.dao.UserDAO#getUserCount() JHCV7$RS
*/ lS:R##
publicint getUserCount()throws HibernateException { B>TI dQ
int count = 0; .7EZB
String querySentence = "SELECT count(*) FROM &ivPY
}bxx]rDl
user in class com.adt.po.User"; `+go|
5N2
Query query = getSession().createQuery Q8sCI An{
%=O$@.%Zc
(querySentence); HxmCKW!
count = ((Integer)query.iterate().next YvP u%=eF
[
queXDn"m
()).intValue(); wcI4Y0+J
return count; WP-'gC6K=
} Fo1|O&>
mlmXFEC
/* (non-Javadoc) 1 n86Mp1.e
* @see com.adt.dao.UserDAO#getUserByPage $EuWQq7OI2
:%hxg
(org.flyware.util.page.Page) v8L&F9
o
*/ +v}R-gNR
publicList getUserByPage(Page page)throws <(%cb.^c=N
ErDt~FH
HibernateException { )5M9Ro7
String querySentence = "FROM user in class 95G*i;E
9ywPWT[^
com.adt.po.User"; .+"SDtoX
Query query = getSession().createQuery T'TxC)
s`$px2Gw
(querySentence); vs)1Rm
query.setFirstResult(page.getBeginIndex()) @Fl&@ $
.setMaxResults(page.getEveryPage()); cKj6tT"=O
return query.list(); [Bz'c1
} uPtHCP6
sa71Vh{
} &2!F:L
.7nr :P
&$?i
"w\Iz]
]GS@ ub
至此,一个完整的分页程序完成。前台的只需要调用 .2jG~_W[
pSq3\#Twr
userManager.listUser(page)即可得到一个Page对象和结果集对象 )n[ oP%
GAlAFsB
的综合体,而传入的参数page对象则可以由前台传入,如果用 M!s@w%0?'
*<**rY*
webwork,甚至可以直接在配置文件中指定。 AjQ^
{P
M zLx2?
下面给出一个webwork调用示例: 7 vS]O$w<4
java代码: ?=]*r>a3
Q(}TN,N
~!,Q<?
/*Created on 2005-6-17*/ O_p:`h:;M
package com.adt.action.user; oR=^NEJv
Ass8c]H@
import java.util.List; <Dr*^GX>?
rX%qWhiEJ
import org.apache.commons.logging.Log; j;O{Hvvz
import org.apache.commons.logging.LogFactory;
V^t5
Y+7
import org.flyware.util.page.Page; s1!_zf_
@
P=eu3
import com.adt.bo.Result; p,=:Ff}~
import com.adt.service.UserService; "}bk
*2
import com.opensymphony.xwork.Action; at/v.U|F
C_[V[k0(
/** lxRzyx
* @author Joa I
[J0r
*/ fWR]L47n
publicclass ListUser implementsAction{ U=C8gVb{Hq
"Q~6cH[#
privatestaticfinal Log logger = LogFactory.getLog |f^/((:D
27vLI~
(ListUser.class); 3mIX9&/
sg(L`P
private UserService userService; H7e/6t<x
fuQ|[tpvQG
private Page page; eo4<RDe<
=GQ?P*x|$
privateList users; xw5E!]~D
?wps_XU
/* lHpo/R:
* (non-Javadoc) [)`9euR%
* *HmL8c
* @see com.opensymphony.xwork.Action#execute() C.{*|#&GAt
*/ icF -`m
publicString execute()throwsException{ _c|>m4+X
Result result = userService.listUser(page); Y"mD)\Bw?
page = result.getPage(); ,>%AEN6N2
users = result.getContent(); 3:a}<^DuCS
return SUCCESS;
]D7z&h
} B{W2D
xXK7i\ny
/** HnVUG4yZTD
* @return Returns the page. 5FHpJlFK,
*/ $2F*p#l(<Z
public Page getPage(){ :&dY1.<N+
return page; j>M
'nQ,;d
} _tQ=ASe0
BNg\;2r
/** Z{/C4" F
* @return Returns the users. `^s(r>2
*/ sp[nKo^
publicList getUsers(){ {"e/3
return users; 0x0.[1mB
} ..7"&-?g{4
1+o >#8D
/** "t8mQ;n
* @param page {!B0&x
* The page to set. TUZ-4{kV"
*/ B| %=<1?
publicvoid setPage(Page page){ amGQ!$]
%#
this.page = page; VVJhQ bP
} C9Fc(Y?_
G#Z%jO-XN
/** 2s
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* @param users Tm_vo-
* The users to set. f9D7T|J?10
*/ \+v_6F
publicvoid setUsers(List users){ b0E(tPw5c
this.users = users; "twV3R
} @?K(+BGi
>}<:5gZtA
/** 7%8,*T
* @param userService -z0,IYG }
* The userService to set. [j}%&$
*/ ~SZ0Yu:X
publicvoid setUserService(UserService userService){ n <lU;
this.userService = userService; wH!]B-hn
} N{P (ym2yR
} 1_/\{quE
D}!U?]la&
{C*mn !u
(7}v}3/
K]@^8e$(
上面的代码似乎看不出什么地方设置了page的相关初值,事实上, t2+m7*76
nI.#A
可以通过配置文件来进行配置,例如,我想每页显示10条记录,那 rN{&$+"2
%dL|i2+*8
么只需要: "=|yM~V
java代码: Ff& VBm
LjXtOF
*kL1r
w6
<?xml version="1.0"?> 5.VA1
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork 7=T0Sa*;
1y_{#,{>
1.0//EN" "http://www.opensymphony.com/xwork/xwork- u
bP2ws
ClVMZ
1.0.dtd"> 43:~kCF[s
sj. eJX"z
<xwork> Um15@p;
vn0XXuquzC
<package name="user" extends="webwork- z]P |%
5yxZ
5Ni!
interceptors"> `iIYZ3i
H7#RL1qM&
<!-- The default interceptor stack name Cj5M
jKI+-s
--> QE)g==d
<default-interceptor-ref i>,5b1x~
RLulz|jC
name="myDefaultWebStack"/> FNmIXpAn*@
<`|}bt
<action name="listUser" ZQl[h7c/N
a%(1#2^`q!
class="com.adt.action.user.ListUser"> W
.Hv2r3
<param l*'jqR')h^
`?=AgGg
name="page.everyPage">10</param> qg.[M*
<result ! h&hPY1
6tG9PG98q9
name="success">/user/user_list.jsp</result> ,=o q)Fm]
</action> .# j)YG
5/P?@`/eT
</package> S*#y7YKI
30<dEoF
</xwork> "-<u.$fE
o{UwUMw5`
3O#7OL68v
[mWo&Ph[-
>454Yir0Mk
T| 4c\
这样就可以通过配置文件和OGNL的共同作用来对page对象设置初值 KDQux
<hy>NM@$
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。 s|,gn 5
X[Y!=e4z
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 4eaC18?
4f"be
VIi|:k
L1rov
msY"Y*4
我写的一个用于分页的类,用了泛型了,hoho Vaq=f/
#M`ijN!Y
java代码: 'd6hQ4Vw4
k,?Y`s
=$BgIt
package com.intokr.util; tvb hWYe
*~ &W?i
import java.util.List; X:62)^~'
}doj4
/** Tm3$|+}$f
* 用于分页的类<br> )2^OBfl7
* 可以用于传递查询的结果也可以用于传送查询的参数<br> 31b-r[B{%
* jjl4A}*0
* @version 0.01 )-jvp8%BK
* @author cheng UBC[5E$
*/ dc?Yk3(Y
public class Paginator<E> { o~iL aN\+
privateint count = 0; // 总记录数 })!n1kt
privateint p = 1; // 页编号 ARU,Wtj#
privateint num = 20; // 每页的记录数 e2B~j3-?z
privateList<E> results = null; // 结果 C|!E'8Rw
>Q+EqT
/**
|qbJ]v!
* 结果总数 ]L&_R^
*/ (V=lK6WQm
publicint getCount(){ O
_1}LS!
return count; /#,<>EfT
} UZ](X/
rSEJ2%iF*
publicvoid setCount(int count){ r2sog{R
this.count = count; Zs{ `Yf^Q
} )Fm
sgB3i`_M
/** j 6v +S
* 本结果所在的页码,从1开始 Y_)04dmr@[
* 4G`YZZQ
* @return Returns the pageNo. B:x4H}`vh
*/ 7Q[P
publicint getP(){ WMUw5h
return p; ]e"NJkcm
} E-"Jgq\aC
MESQAsx%
/** }W|CIgF*
* if(p<=0) p=1 w[|!$J?
* 1m![;Pg3
* @param p 'GW@P
*/ }y[o[>
publicvoid setP(int p){ {O^1WgGc[
if(p <= 0) 5 !NPqka}.
p = 1; #bdJ]v.n
this.p = p; 5Cz:$-+
}
=6A<>
T+.wJW:jh
/** Y":hb;&
* 每页记录数量 VUt
6[~?
*/ )?TJ{'m
publicint getNum(){ 7NXT.E~2
return num; GzR;`,_O/
} H"&N<"hw
[yVU
p+
/** h2BD?y
* if(num<1) num=1 ix$+NM<n
*/ Jp,ohVRNq
publicvoid setNum(int num){ nwkhGQ
if(num < 1) P4N{lQ.>
num = 1; !.w S+
this.num = num; f9\7v_
} E=x\f "Z
\+>b W(
/** T[;{AXLeI
* 获得总页数 $==hr^H
*/ hi
]+D= S
publicint getPageNum(){ =oHJ_
return(count - 1) / num + 1; };KmMpBn
} S%T1na^x
4a646jg)
/**
(h%wO
* 获得本页的开始编号,为 (p-1)*num+1 i$NnHj|
*/ jgO{DNe(=
publicint getStart(){ j5HOdy2
return(p - 1) * num + 1; dm 2_Fj
} Q,DumOq
t)v#y!Ci"
/** {Rz`)qqE
* @return Returns the results. v~xG*e
*/ ims *|~{sr
publicList<E> getResults(){ Cn{UzSKfs
return results; X:!%"K%}
} "xO`&a{
VtmUK$k}I
public void setResults(List<E> results){ DV.MvFV
this.results = results;
:?^(&3;
} ~\kRW6
9GGBJTk-
public String toString(){
)3 v8
StringBuilder buff = new StringBuilder c,-< 4e
nh8h?&q|
(); ]v#T'<Nl
buff.append("{"); 6zI?K4o
buff.append("count:").append(count); ?IWLl
buff.append(",p:").append(p); TfxKvol'
buff.append(",nump:").append(num); 3)eeUO+
buff.append(",results:").append 6Q>w\@lF
Nyo6R9^
(results); vLC&C-f
buff.append("}"); zzx4;C",u
return buff.toString(); 0-#ct1-
} {C6Yr9
Y}[r`}={
} REsThB
" DFg"
g 08
`=g