Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 rJTYCe1*
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 2lCgUe)N
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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 +lX Iv
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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 uznYLS
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分页支持类: ~:
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java代码: y=aWSb2y'
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package com.javaeye.common.util; `TYC]9
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import java.util.List; ?iZM.$![
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publicclass PaginationSupport { H_JE)a:+
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publicfinalstaticint PAGESIZE = 30; ckb(+*+l
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privateint pageSize = PAGESIZE; &Hyy .a
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privateList items; WH"'Ju5}
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privateint totalCount; FUXJy{n6"2
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privateint[] indexes = newint[0]; 2acTw#
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privateint startIndex = 0; k 1a?yH)=
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public PaginationSupport(List items, int J(K/z,4h
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totalCount){ A.mFa1lH
setPageSize(PAGESIZE); gnkeJ}K
setTotalCount(totalCount); 3:G$Y:#P
setItems(items); ?6\N&MTF
setStartIndex(0); (?g+.]Dt,
} $)nPj_h
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public PaginationSupport(List items, int Qv`: E
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totalCount, int startIndex){ -L4G)%L\
setPageSize(PAGESIZE); cIQbu#[@
setTotalCount(totalCount); 9Zj3 "v+b
setItems(items); eXD~L&s[
setStartIndex(startIndex); ce#Iu#qT
} ~-[!>1!%
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public PaginationSupport(List items, int UmvnVmnv
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totalCount, int pageSize, int startIndex){ H3*]}=
setPageSize(pageSize); \<(EV,m2
setTotalCount(totalCount); V9SL96'[I
setItems(items); pdR\Ne0P*
setStartIndex(startIndex); W!R0:-
} =.CiKV$E
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publicList getItems(){ >e&
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return items; |1tpXpe
} ,`RX~ H=C
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publicvoid setItems(List items){ .)$MZyo
this.items = items; XVqkw@Ia4!
} 7M4J{}9
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publicint getPageSize(){ :N _]*>
return pageSize; {| hg3R~A
} Z'j[N4%BK
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publicvoid setPageSize(int pageSize){ SepwMB4@
this.pageSize = pageSize; g)^s+Y
} gSw4\ R
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publicint getTotalCount(){ /hu>MZ(\
return totalCount; 7 s{vou
} ,dTmI{@O
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publicvoid setTotalCount(int totalCount){ p&x!m}!
if(totalCount > 0){ x 55W"q7
this.totalCount = totalCount; tB"9%4](
int count = totalCount / ^Z#G_%\Y:
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pageSize; " (O3B
if(totalCount % pageSize > 0) RC[Sa wA
count++; K$Vu[!l`
indexes = newint[count]; OqIXFX"
for(int i = 0; i < count; i++){ -$o0P'Vx
indexes = pageSize * -*4*hHmb
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} #f) TAA
}else{ "lw|EpQk`
this.totalCount = 0; c/tB_]
} z8ZQL.z%h
} GnW MI1$
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publicint[] getIndexes(){ [Cv./hEQi
return indexes; [ ,Go*r
} #l4T/`u'9!
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publicvoid setIndexes(int[] indexes){ =oSd M2
this.indexes = indexes; ]5S`y{j1
} F!EiF&[\J
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publicint getStartIndex(){ Xj/z),
return startIndex;
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} K-C,n~-
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publicvoid setStartIndex(int startIndex){ d6QrB"J`
if(totalCount <= 0) }l7+W4~
this.startIndex = 0; H/*ol^X7
elseif(startIndex >= totalCount) 1]2]l*&3
this.startIndex = indexes ~SQxFAto
h7"U1'b
[indexes.length - 1]; k(dakFaC^
elseif(startIndex < 0) UrvUt$WO
this.startIndex = 0; 0wv#AT
else{ 0Xh_.PF
this.startIndex = indexes D:/ n2_
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[startIndex / pageSize]; `sCaGCp
} 8J(j}</>a
} NVv
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publicint getNextIndex(){ wI_@
int nextIndex = getStartIndex() + DQXUh#t\(]
?8V.iHJk
pageSize; #_ |B6!D!
if(nextIndex >= totalCount) }R['Zoh4I
return getStartIndex(); [v"Z2F<.=
else `3rwqcxA
return nextIndex; Wgls+<l8
} ;AEfU^[
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publicint getPreviousIndex(){ 2@zduL'do_
int previousIndex = getStartIndex() - g^]Iw~T6$
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pageSize; ':wf%_Iw
if(previousIndex < 0)
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return0; J2W-l{`r<
else ~:z.Xu5m
return previousIndex; Pq omi!1
} LW]fme<V?
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} K?^;|m-
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抽象业务类 ^&eF916H
java代码: BY6#dlDi
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/** K|7"YNohfG
* Created on 2005-7-12 fc9;ZX7
*/ M5`v^>
package com.javaeye.common.business; At(88(y-W
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import java.io.Serializable; a$My6Qa#
import java.util.List; \HeJc:^
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import org.hibernate.Criteria; buGBqx[
import org.hibernate.HibernateException; OpUfK4U)
import org.hibernate.Session; ?,vLRq.
import org.hibernate.criterion.DetachedCriteria; T`bYidA
import org.hibernate.criterion.Projections; &GP(yj]
import g&Vhu8kNIA
DB' 0
org.springframework.orm.hibernate3.HibernateCallback; RaJTya^
import <|Td0|x
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org.springframework.orm.hibernate3.support.HibernateDaoS PF{uaKWk
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upport;
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import com.javaeye.common.util.PaginationSupport; #I/P9)4
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public abstract class AbstractManager extends VdHT3r
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HibernateDaoSupport { U%q)T61
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privateboolean cacheQueries = false; V"/.An|
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privateString queryCacheRegion; -c`xeuzK'
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publicvoid setCacheQueries(boolean mrTf["K
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cacheQueries){ @ st>#]i4
this.cacheQueries = cacheQueries; [?]N
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} 7H7
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publicvoid setQueryCacheRegion(String [EAOk=X
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queryCacheRegion){ bfxE}>
this.queryCacheRegion = 5nG\J
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queryCacheRegion; W5R/Ub@g
} m}]{Y'i]R
&;BhL%)}
publicvoid save(finalObject entity){ QiPqN$n
getHibernateTemplate().save(entity); _}l(i1o,/
} |+cz\+
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publicvoid persist(finalObject entity){ <y6`8J7:
getHibernateTemplate().save(entity); PQHztS"
} -)V0D,r$[
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publicvoid update(finalObject entity){ pzF_g-B
getHibernateTemplate().update(entity); T\6Qr$t
} X`8<;l
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publicvoid delete(finalObject entity){ 1-kuK<KR
getHibernateTemplate().delete(entity); <5zR-UA>
} oC&}lp)q
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publicObject load(finalClass entity, }+,Q&]>~
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finalSerializable id){ j+jC
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return getHibernateTemplate().load j*%#~UFw
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(entity, id); Pf;OYWST
} uYC^&siS<s
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publicObject get(finalClass entity, gwj?.7N*k
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finalSerializable id){ {cdICWy(F3
return getHibernateTemplate().get ;}B=g/C
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(entity, id); #qd!_oN
} >tg)F|@
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publicList findAll(finalClass entity){ (Jq m9
return getHibernateTemplate().find("from 5_^d3LOT0x
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" + entity.getName()); hb[ThQ
} ?$pNd uE
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publicList findByNamedQuery(finalString %`Ce#b()'
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namedQuery){ \'O/3Y7?X
return getHibernateTemplate )<x9t@$
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().findByNamedQuery(namedQuery); >N^<Q4%2
} cW3'057
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publicList findByNamedQuery(finalString query, 49FP&NgK
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finalObject parameter){ {4+/0\
return getHibernateTemplate :!i=g+e]
cS.@02~f"
().findByNamedQuery(query, parameter); 5<Kt"5Z%7
} B)q }]Qn
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publicList findByNamedQuery(finalString query, U&3!=|j
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finalObject[] parameters){ C|y^{4|R
return getHibernateTemplate 7w73,r/D8A
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().findByNamedQuery(query, parameters); -Mo4`bN
} MR
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publicList find(finalString query){ {aE[h[=r
return getHibernateTemplate().find u6C_*i{2
fw %p_Cm
(query); C:1(<1K
} a`Bp^(f}
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publicList find(finalString query, finalObject dV$[O`F*b
a" s2N%{
parameter){ B7Ket8<J
return getHibernateTemplate().find 60{G
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(query, parameter); jTwSyW
} bB@=J~l4
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public PaginationSupport findPageByCriteria $NCvF'
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(final DetachedCriteria detachedCriteria){ s}JifY`
return findPageByCriteria 'v'[_(pq
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); u?>},M/
} s:{[Y7\?
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public PaginationSupport findPageByCriteria W2`3 p
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(final DetachedCriteria detachedCriteria, finalint %)i&|AV"
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startIndex){ Vg62HZ |
return findPageByCriteria zd_N' :6
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(detachedCriteria, PaginationSupport.PAGESIZE, #>yOp *
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startIndex); i~x]!!
} EG4~[5[YgI
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public PaginationSupport findPageByCriteria h.-L_!1B7
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(final DetachedCriteria detachedCriteria, finalint `K VSYC
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pageSize, )EMlGM'2q
finalint startIndex){ 5CnNp?.t^
return(PaginationSupport) `U0XvWPr[
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getHibernateTemplate().execute(new HibernateCallback(){ 9ad`q+kY
publicObject doInHibernate C32*RNG?U
f)vnm*&-
(Session session)throws HibernateException { xS,F
DPA
Criteria criteria = #Q2s3"X[
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detachedCriteria.getExecutableCriteria(session); i:Y5aZc/Ds
int totalCount = t7-r YY(
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((Integer) criteria.setProjection(Projections.rowCount ?uCL[
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()).uniqueResult()).intValue(); [cDkmRV
criteria.setProjection R?{_Q<17
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(null); m
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List items = )E9c6'd
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criteria.setFirstResult(startIndex).setMaxResults ]9_tto!/
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(pageSize).list(); ]U@~vA#''
PaginationSupport ps = q1HJ_y
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new PaginationSupport(items, totalCount, pageSize, "T[BSj?E
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startIndex); L=54uCv
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return ps; u ^#UsOt+
} %i7U+v(d
}, true); UNSXr`9
} C}9GrIi
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public List findAllByCriteria(final Lapeh>1T
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DetachedCriteria detachedCriteria){ U8aVI
return(List) getHibernateTemplate /IcGJ&;
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().execute(new HibernateCallback(){ {zd[8TJ~xa
publicObject doInHibernate +DQUL|\
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(Session session)throws HibernateException { \ v+>qY<q
Criteria criteria = T!?tyW
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detachedCriteria.getExecutableCriteria(session); ?(zCv9Pg
return criteria.list(); AP z"k?D0
} tvno3"
}, true); 3AENY@*
} )cL(()N
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public int getCountByCriteria(final d<Lc&wlP
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DetachedCriteria detachedCriteria){ YXTV$A+lW
Integer count = (Integer) s;Bh69
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getHibernateTemplate().execute(new HibernateCallback(){ YeT{<9p
publicObject doInHibernate K%`]HW@I{
C ]B P}MY<
(Session session)throws HibernateException { qh W]Wd"g
Criteria criteria = DXj>u9*%
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detachedCriteria.getExecutableCriteria(session); QiA}0q3]0
return H9'psv
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criteria.setProjection(Projections.rowCount tKyGD|g S
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()).uniqueResult(); s[eSPSFZ
} Q%~BD@Io
}, true); Fnk@)1
return count.intValue(); 3 ;" [WOv
} /
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} A*:|d~
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用户在web层构造查询条件detachedCriteria,和可选的 "{+2Q
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 TH y?Y
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PaginationSupport的实例ps。 \7h>9}wGf
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ps.getItems()得到已分页好的结果集 J9t?;3
ps.getIndexes()得到分页索引的数组 *otgI"y\
ps.getTotalCount()得到总结果数 H;<>uELie
ps.getStartIndex()当前分页索引 `z q+Xl
ps.getNextIndex()下一页索引 z{
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ps.getPreviousIndex()上一页索引 &:ZR% f
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 9iJ$M!
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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 UpD4'!<buV
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一下代码重构了。 _UZPQ[
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我把原本我的做法也提供出来供大家讨论吧: ckV\f({
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首先,为了实现分页查询,我封装了一个Page类: T(Yp90'6
java代码: G0Z5 h
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/*Created on 2005-4-14*/ }:0ru_F)(4
package org.flyware.util.page; QL7.QG
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/** (f_YgQEL
* @author Joa | @ ut/
* [aA@V0l
*/ fwA8=oSZd
publicclass Page { Y+),c14#
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/** imply if the page has previous page */ zx$1.IM"4
privateboolean hasPrePage; du~V=%9
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/** imply if the page has next page */ 4sORp^t'Q
privateboolean hasNextPage; rp"5176
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/** the number of every page */ Nr]Fh
privateint everyPage; Sx
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HnjA78%i
/** the total page number */ djnES,^%9
privateint totalPage; MCEHv}W
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/** the number of current page */ 5y
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privateint currentPage;
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/** the begin index of the records by the current G!B:>P|\l
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query */ {Ak
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privateint beginIndex; )=iv3nF?6N
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/** The default constructor */ +XO\#$o>W
public Page(){ -n[(0n3c
}
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} 7$g$p&,VX
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/** construct the page by everyPage K, !
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* @param everyPage Z- a
* */ eCsk\f`
public Page(int everyPage){ U+>M@!=
this.everyPage = everyPage; _4)z:?G5
} &wY$G! P
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/** The whole constructor */ =9 )k:S(
public Page(boolean hasPrePage, boolean hasNextPage, [PUu9rz#
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int everyPage, int totalPage, -3)jUzD
int currentPage, int beginIndex){ [|c%<|d2
this.hasPrePage = hasPrePage; ;>5`Y8s6
this.hasNextPage = hasNextPage; itirh"[
this.everyPage = everyPage; M.s'~S7y
this.totalPage = totalPage; 1d FuoX
this.currentPage = currentPage; 8 I_
this.beginIndex = beginIndex; "|1iz2L
} 7M7Ir\d0lp
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/** {]}94T~/k
* @return mgVYKZWL-i
* Returns the beginIndex. $57b.+2n
*/ p$|7T31 *
publicint getBeginIndex(){ eZU9L/w:
return beginIndex; -j]k^
} jMTM:~0N
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/** 7`A]X,:
* @param beginIndex RQo
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* The beginIndex to set. <]1,L%
*/ K6-M .I
publicvoid setBeginIndex(int beginIndex){ |]@Pq[Hn|
this.beginIndex = beginIndex; VSDua.
} T#3@r0M
D%yY&q;
/** ML\>TDt
* @return kO3\v)B;
* Returns the currentPage. Pb8@owG8
*/ "#o..?K
publicint getCurrentPage(){ CKK}Z;~:
return currentPage; ]r|oNGD)G
} :[_msd
1
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/** "t.`/4R2w
* @param currentPage q{Z#}|km#
* The currentPage to set. m?<E >-bI
*/ 1F`jptVQ\G
publicvoid setCurrentPage(int currentPage){ Px=@Tw N,
this.currentPage = currentPage; 6^'BTd
} -g2l-N{&
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/** X@DW1<wEt
* @return 2,q*[Kh1
* Returns the everyPage. 2NMs-Zs
*/ %k1Pyv;]
publicint getEveryPage(){ u>"0>U
return everyPage; K$M+"#./
} mvZ#FF1,J
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/** (n*:LS=0
* @param everyPage p8!T)
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* The everyPage to set. A'KH_])
*/ \|S!g_30m
publicvoid setEveryPage(int everyPage){ _/I">/ivlM
this.everyPage = everyPage; P$z_A8}
} 1Q>nS[
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/** ;cI*"-I:F
* @return \4>,L_O
* Returns the hasNextPage. =otO@22Np
*/ I}
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publicboolean getHasNextPage(){ 3@gsKtA&H4
return hasNextPage; V|_
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} O[C4xq
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/** !o /=,ZIx
* @param hasNextPage Eu`|8# [ W
* The hasNextPage to set. c[,h|~K/_?
*/ [Vo5$w
publicvoid setHasNextPage(boolean hasNextPage){ V9<`?[Usv
this.hasNextPage = hasNextPage; RPW46l34
} @m#OhERv
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/** 3OZPy|".ax
* @return K] (*l"'U5
* Returns the hasPrePage. 1g{Pe`G,
*/ C}RO'_Pq
publicboolean getHasPrePage(){ Mu?|<#s
return hasPrePage; hL&$` Q
} aaR& -M@
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/** 4a-JC"
* @param hasPrePage =n5'~1?X?
* The hasPrePage to set. H&)}Z6C"
*/ +P2oQ_Fk`9
publicvoid setHasPrePage(boolean hasPrePage){ !5o j~H
this.hasPrePage = hasPrePage; e|\xFV=4
} gA!@oiq@
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/** 5G f@n/M"
* @return Returns the totalPage. T+<.KvO-
* -!j6&
*/ q<dG}aj
publicint getTotalPage(){ *5%vU|9b
return totalPage; nF,F#V8l
} T-en|.
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/** _p-e)J$7
* @param totalPage &J>e;X
* The totalPage to set. N*o{BboK;
*/ UZyg_G6
publicvoid setTotalPage(int totalPage){ t}YcB`q)
this.totalPage = totalPage; f4"UI-8;n
} ]4l2jY
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} hIJtu;}zU
}5;4'l8
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上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 [IL*}M!
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个PageUtil,负责对Page对象进行构造: =yf)Z^
java代码: s@F&N9oh
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/*Created on 2005-4-14*/ tVAi0`DV
package org.flyware.util.page; SYCL\b
n)e2?
import org.apache.commons.logging.Log; LhJUoX
import org.apache.commons.logging.LogFactory; : ky`)F`
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/** >JyS@j}
* @author Joa H7zN|NdNw
* jRJG .hcB5
*/ xZ'fer`&
publicclass PageUtil { 'C1lP)S5
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privatestaticfinal Log logger = LogFactory.getLog Bf utmI
oac)na:O#
(PageUtil.class); *F\wWg'!B
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/** tT}b_r7h(1
* Use the origin page to create a new page +Nt4R:N
* @param page `6Bx8CZ'I
* @param totalRecords v:t;Uk^Y
* @return l0qaTpn
*/ 1Bj.MQ^
publicstatic Page createPage(Page page, int |P
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totalRecords){ !eW1d0n'+f
return createPage(page.getEveryPage(), K:,V>DL
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page.getCurrentPage(), totalRecords); PkvW6,lS
} ;4nY{)bD
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/** >q"dLZ
* the basic page utils not including exception Cj-s
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handler TSB2]uH
* @param everyPage 9@ k8$@
* @param currentPage cOV j @z
* @param totalRecords Gv-VDRS
* @return page O~3
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*/ Qg4D*r\|@
publicstatic Page createPage(int everyPage, int qSY\a\.<
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currentPage, int totalRecords){ Rb6BY-/J
everyPage = getEveryPage(everyPage); 2bt>t[0ad
currentPage = getCurrentPage(currentPage);
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int beginIndex = getBeginIndex(everyPage, q$:1Xkl
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currentPage); %7#<K\])
int totalPage = getTotalPage(everyPage, OX_y"]utU
B)0/kY7c
totalRecords); .5|[gBK
boolean hasNextPage = hasNextPage(currentPage, cl& w/OJ#
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totalPage); V*vQNPey
boolean hasPrePage = hasPrePage(currentPage); -S sgW
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returnnew Page(hasPrePage, hasNextPage, Qi18q|l8v
everyPage, totalPage, ]
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currentPage, 7^eyO&4z
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beginIndex); 67j kU!
} j~q 7v
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y=Y k$:-y
privatestaticint getEveryPage(int everyPage){ Zxebv#4
return everyPage == 0 ? 10 : everyPage; .n8R%|C5
} ]s\r3I]
z !K2UTX
privatestaticint getCurrentPage(int currentPage){ 7HPwlS
return currentPage == 0 ? 1 : currentPage; jSI1tW8
} wHLQfrl0
E7X6RB b
privatestaticint getBeginIndex(int everyPage, int odhcD;^X1
mskG2mA
currentPage){ 4.O) /0sU
return(currentPage - 1) * everyPage; XZE(& (s
} G5}_NS/
b}!
cEJY
privatestaticint getTotalPage(int everyPage, int "wcaJ;Os
+~8Lc'0aA
totalRecords){ 8zK#./0\
int totalPage = 0; 'uu*DgEr
]IuZ T
if(totalRecords % everyPage == 0) j7}mh
totalPage = totalRecords / everyPage; ,=)DykP
else zluq2r
totalPage = totalRecords / everyPage + 1 ; \BHZRytQF
6H|SiO9
return totalPage; OyO<A3
} 6z\!lOVjb
a 0SZw
privatestaticboolean hasPrePage(int currentPage){ W@R7CQE@
return currentPage == 1 ? false : true; Ed=/w6<
} ,Fn;*
[2@:jLth=
privatestaticboolean hasNextPage(int currentPage, IdmP!(u
![z2]L+TB
int totalPage){ R27'00(Z0
return currentPage == totalPage || totalPage == `l|Oj$
oCT,v 0+4O
0 ? false : true; e$9a9twl
} L^qCE-[
|f_'(-v`E
c.>f,vtcn
} >Na. C(DZ
&M|rRd~*
/stvNIEa
8a6.77c
[n"eD4 )K|
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 Xt$qjtVM
6wp1jN
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 ?mNB:-Q
6,q0F*q
做法如下: OY1bFIE
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 {
j_-iF
]xRR/S4
的信息,和一个结果集List: i!YfR]"}
java代码: _hY6NMw
?o(284sV3
LATizu
/*Created on 2005-6-13*/ "`M~=RiI
package com.adt.bo; d(^8#4
Bz'.7"
":0
import java.util.List; 0moA mfc
l%+ &V^:
import org.flyware.util.page.Page; kqB# 9
V Rv4p5
/** #Us<#"fC
* @author Joa 4U dk#
*/ > TYDkEs0
publicclass Result { Noj*K6
nmpc<&<<
private Page page; P5my]4|x
"G%S
m")
private List content; ,$`}Rf<
d>[i*u,]/
/** xoVd[c!
* The default constructor (Z<@dkO?)
*/ b_sasZo
public Result(){ p@pb[Bx~[
super(); +pYgh8w@
} w10~IP
|47t+[b
/** ^p(aZj3k
* The constructor using fields QtfL'su:
* w6Gez~8
* @param page /T6bc^nOW
* @param content *Xnf}Ozx
*/ ?=lb@U
public Result(Page page, List content){ U-DQ?OtmC@
this.page = page; |mMsU,*gB
this.content = content; R+.4|1p
} k2Cq9kQ q
XoD:gf
/** ^?{&v19m
* @return Returns the content. B-g-T>8
*/ 'jO2pH/%
publicList getContent(){ _N;@jq\q
return content; +C\79,r
} e(w c
[bv
(+gTIcc
>
/** NrS+N;i
* @return Returns the page. }@LIb<Y
*/ 0V6, &rTF
public Page getPage(){ q25p3
return page; 6n/=n%US
} }Rz,}^B
g5U,
/**
IZrcn
* @param content Ch{6=k bK
* The content to set. Lu^uY7
?}
*/ Pfs_tu
public void setContent(List content){ MP}-7UA#K
this.content = content; B^9C}QB
} Sm[#L`eqW
hqeknTGsIn
/** +6>2= ,?Z
* @param page r1F5'?NZ(0
* The page to set. xJw"
8V<
*/ 3B;Gm<fJ9N
publicvoid setPage(Page page){ l\0PwD
this.page = page; [;hkT
} rXmrT%7k
} <
e3] pM
L[PqEN\i
)'jGf;du
M#Z^8(
E
1`g8Hk'
2. 编写业务逻辑接口,并实现它(UserManager, KT<i%)t2
1/1oT
UserManagerImpl) \4qF3#
java代码: rmBzLZ}
47Vt8oyh%
UxMy8}w!y
/*Created on 2005-7-15*/ #&uajo
package com.adt.service; q2|x$5
oeKl\cgFx
import net.sf.hibernate.HibernateException; sRLjKi2D
lq-F*r\/~+
import org.flyware.util.page.Page; o[wiQ9Tl
\RDqW+,
import com.adt.bo.Result; el<Gd.p.d
1\Bh-tzB
/** auIW>0?}
* @author Joa [-Z 6QzT
*/ Z*P/ ubV'
publicinterface UserManager { \1-lda
[Y@}{[q5
public Result listUser(Page page)throws A'![*O
Jv
5l
HibernateException; }JOz,SQHP
>=rniHs=?7
} iuqJPW^}
>r)UDa+
_s-X5xU
Y,mo}X<>
.z$UNB(!M
java代码: <NDV 5P
44n41.Q]
[
s/j?/9
/*Created on 2005-7-15*/ *fd:(dN|
package com.adt.service.impl; 6(\-aH'Ol
f dJg7r*
import java.util.List; }x{1{Bw>Y
g<F+Ldgj
import net.sf.hibernate.HibernateException; `6Q+N=k~Z
)y!gApNs"
import org.flyware.util.page.Page; oT:wGBW
import org.flyware.util.page.PageUtil; 6_8y Q
~D/Lo$K"
import com.adt.bo.Result; UC`sq-n
import com.adt.dao.UserDAO; ZQR)k:k7
import com.adt.exception.ObjectNotFoundException; J#w=Z>oz <
import com.adt.service.UserManager; %26HB
w=JF
\4G9fR4
/** 7!o#pt7
* @author Joa cWQ &zc
*/ W }Ll)7(|T
publicclass UserManagerImpl implements UserManager { CyVi{"aF3
]We0 RD"+
private UserDAO userDAO; @d5t%V\
iN Lt4F[i
/** &B+_#V=X@
* @param userDAO The userDAO to set. L`:V]p
*/ KKg\n^
publicvoid setUserDAO(UserDAO userDAO){ /ml+b8@
this.userDAO = userDAO; z{NK(oW
} v!S(T];)
4;jAdWj3
/* (non-Javadoc) RT%{M1tkS
* @see com.adt.service.UserManager#listUser dn%'bt
sV%=z}n=
(org.flyware.util.page.Page) 'L1yFv
*/ ncsk(`lo
public Result listUser(Page page)throws m,4'@jg0
vl`St$$|
HibernateException, ObjectNotFoundException { s}^W2
int totalRecords = userDAO.getUserCount(); VzM (u_)
if(totalRecords == 0) B( wi+;
throw new ObjectNotFoundException @71y:)W<
%
5!Y#$:{o
("userNotExist"); ZE/Aj/7Qy
page = PageUtil.createPage(page, totalRecords); =*?XZA)c
List users = userDAO.getUserByPage(page); 0KZsWlD:L
returnnew Result(page, users); s BuXwa
} z.t,qi$;{U
~a>3,v-
} Ac>GF
-zH-9N*c
TU| 0I
Pj^Ccd'>=
>LU !Z
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 xLbF9ASim
CS xB)-
询,接下来编写UserDAO的代码: Vx n-
3. UserDAO 和 UserDAOImpl: 1ww~!R
java代码: &9n=!S'Md
;[,#VtD
h9%.tGx
/*Created on 2005-7-15*/ 1(VskFtZF
package com.adt.dao; z)&&Ym#
]V"B`ip[2
import java.util.List; U`4t4CHA
Bo*Wm
w
import org.flyware.util.page.Page; w 3L+7V,!
$yZP"AsAR
import net.sf.hibernate.HibernateException; 51>OwEf<R
,v*\2oG3^
/** m`,h nDp
* @author Joa BQ~\ p\
*/ gqAN-b'
publicinterface UserDAO extends BaseDAO { oFu( J
;sSRv9Xb
publicList getUserByName(String name)throws \D! I"mr
g+k
yvI7o
HibernateException; Ys%d
x1`Jlzrp,
publicint getUserCount()throws HibernateException; Wc/B_F?2
Dd,]Y}P
publicList getUserByPage(Page page)throws [4}U*\/>C
*_uGzGB&G
HibernateException; ];Bk|xJ/>
qS[nf>"
} ,5|@vW2@u
8rjiW#
gM
v0[~;u
^+dL7g?+
eG5xJA^
java代码: KlRIJOS
4Cf.%f9@
s9?H#^Y5u
/*Created on 2005-7-15*/ 5bprhq-7
package com.adt.dao.impl; k?Iq 6
0~nub
import java.util.List; MJ@PAwv"
*2I@_b6&
import org.flyware.util.page.Page; /3 ;t
&]
SDW!9jm>R
import net.sf.hibernate.HibernateException; @(e/Y/
import net.sf.hibernate.Query; eq36mIo
^pvnUODW[
import com.adt.dao.UserDAO; flU?6\_UC
wb-_CQ
/** Cy\! H&0wg
* @author Joa &o)eRcwH`
*/ WS ^%<
h#
public class UserDAOImpl extends BaseDAOHibernateImpl ohB@ij C!
ncij)7c)u
implements UserDAO { p w`YMk
3gba~}c)
/* (non-Javadoc) +C[%^G-:
* @see com.adt.dao.UserDAO#getUserByName O>2i)M-h9x
<SNu`,/I
(java.lang.String) (yhnv Z
*/ MvlqxJ$
publicList getUserByName(String name)throws a"X9cU[
BP0*`TY
HibernateException { s\
YHT.O?
String querySentence = "FROM user in class hdH}4W
/.[78:G\,
com.adt.po.User WHERE user.name=:name"; hW-?j&yJ?
Query query = getSession().createQuery e:RgCDWL
JE/Kf<
(querySentence); [Xo[J?w],2
query.setParameter("name", name); eq$.np
return query.list(); |Skhx9};
} kG3m1: :
Zm/I &
/* (non-Javadoc) 2G BE=T
* @see com.adt.dao.UserDAO#getUserCount() .OSFLY#[?
*/ IX 2 dic'
publicint getUserCount()throws HibernateException { =$Sd2UD
int count = 0; Q)\4 .d
String querySentence = "SELECT count(*) FROM F]KAnEf
qgw)SuwW
user in class com.adt.po.User"; {3*Zx"e![
Query query = getSession().createQuery B)u*c]<qU
5TS&NefM
(querySentence); ps3jw*QZ{5
count = ((Integer)query.iterate().next p`06%"#
'/QS
sZR
()).intValue(); Hn!13+fS
return count; BBlYy5x
} ,LVZ
'o]8UD(
/* (non-Javadoc) 8(""ui8
* @see com.adt.dao.UserDAO#getUserByPage i5jsM\1j
,\=,,1_
(org.flyware.util.page.Page) ='<789wT
*/ Ni-@El99
publicList getUserByPage(Page page)throws i9j#Tu93 f
[e;c)XS[
HibernateException { q=`i
String querySentence = "FROM user in class 6h:2,h
pE
S<UWv@`U"
com.adt.po.User"; ?_nbaFQK3
Query query = getSession().createQuery %,Lv},%Y
aV`_@F-8
(querySentence); b,uudtlH
query.setFirstResult(page.getBeginIndex()) I::|d,bR!
.setMaxResults(page.getEveryPage()); &Na,D7A:3I
return query.list(); OV,t|
} yU'<b.]
aGq1YOD[$
} VHqHG`}:
\2!1fN
YML]pNB
rc`}QoB)R
cogIkB&Ju
至此,一个完整的分页程序完成。前台的只需要调用 ! N'HL-oT
d=d*:<Zx
userManager.listUser(page)即可得到一个Page对象和结果集对象 1U6z2i+y
dpSNh1
的综合体,而传入的参数page对象则可以由前台传入,如果用
jH>`:
wGg_ vAn
webwork,甚至可以直接在配置文件中指定。 +FJ+,|i
h yK&)y?~
下面给出一个webwork调用示例: zv0bE?W9
java代码: Lz{z~xNHW.
<NXJ&xs-+
xtO#reL"q?
/*Created on 2005-6-17*/ `Vl9/IEk
package com.adt.action.user; ?"$Rw32
<NWq03:&
import java.util.List; 5y8VA4L/o
`3yK<-
import org.apache.commons.logging.Log; fLS].b]1N
import org.apache.commons.logging.LogFactory; 55Y a(E
import org.flyware.util.page.Page; o3YW(%cYR
&&g02>gE
import com.adt.bo.Result; /V
GI@"^v
import com.adt.service.UserService; &P7Z_&34Z
import com.opensymphony.xwork.Action; CorV!H4
gCq'#G\Z
/** #MFIsx)r
* @author Joa LhRd0
*/ 10_#Z~aU
publicclass ListUser implementsAction{ G>Hg0u0!,
< 1[K1'7h
privatestaticfinal Log logger = LogFactory.getLog EpH_v`
6n^@Ps
(ListUser.class); O,JS*jXl
_"*}8{|
private UserService userService; H*e +
2
cj9C6Y!
private Page page; S5V:H Rj{?
"VDMO^
privateList users; [ ou$*
Gk]ZP31u
/* ,u>[cRqw
* (non-Javadoc) @VPmr}p:{
* P0pBR_:o
* @see com.opensymphony.xwork.Action#execute() *YSRZvD<\
*/ zz
/4 ()u
publicString execute()throwsException{ \<ysJgqUG
Result result = userService.listUser(page); ~Up{zRD"B
page = result.getPage(); oKb"Ky@s
users = result.getContent(); (zh[1[a
return SUCCESS; )+R n[MMp
} j+@3.^vK
<v'&Pk<
/** UWidT+'Sa
* @return Returns the page. Vd(n2JMtG
*/ tj$[szo
public Page getPage(){ ES?*w@x
return page; <Se9aD
} S*$?~4{R
2;u
i'B
/** 4hODpIF
* @return Returns the users. 0Ni{UV?
k
*/ +FAj30
publicList getUsers(){ H>A6VDu
return users; Fj(GyPFG
} Rq%Kw> {&
X fqhD&g
/**
r5Tdp)S
* @param page &iVdqr1,
* The page to set. vj]>X4'i
*/ ,|B-Nq
publicvoid setPage(Page page){ z V\+za,
this.page = page; H=Ilum06
} Yu>DgMW
CF2Bd:mfZ
/** kJp~'\b
* @param users >a,D8M?
* The users to set. =jJEl=*S
*/ Z sTtSM\Ac
publicvoid setUsers(List users){ hg(<>_~
this.users = users; }}{n|l+R5
} qfyZda0d
{VE
h@yn
/** b1KtSRLV
* @param userService `X}:(O^GO
* The userService to set. ylKK!vRHT
*/ ^Aq0<
publicvoid setUserService(UserService userService){ k(l2`I4V
this.userService = userService; w_xca(
} /}(d'@8p
} m|;(0
rft
/v8Q17O?e
RhH1nf2UR
lGl'A}]#$
3 /@z4:p0R
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, %, kP_[!>Q
&$F<]]&
可以通过配置文件来进行配置,例如,我想每页显示10条记录,那 x8PT+KC
|)29"_Kk5
么只需要: pn
gto
java代码: 6'r8.~O
s|]g@czan
~ELMLwn.
<?xml version="1.0"?> qW0:q.
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork sQvRupYRO
:oP LluW*
1.0//EN" "http://www.opensymphony.com/xwork/xwork- :TH cI;PG8
tcuwGs>_
1.0.dtd"> U]iI8c
QO/0VB42
<xwork> 50W+!'
["Ltqgx
<package name="user" extends="webwork- 2T~cOH;T
CWn\KR
interceptors"> :$MOdL[ir
6Dlm.~G
<!-- The default interceptor stack name <Kd(fFe
Q +^&
--> [1VA`:?W
<default-interceptor-ref QPJ\Iu@D$
elOeXYO0
name="myDefaultWebStack"/> G%<}TI1}
Nr~$i% [
<action name="listUser" N{;!xIv
J:L+q}A
class="com.adt.action.user.ListUser"> MzJCiX^
<param $fFh4O4
K4K]oT
name="page.everyPage">10</param> /YHAU5N/}
<result VL2+"<
^&Wa?
m.
name="success">/user/user_list.jsp</result> O#72h]
</action> A8U\/GP
s>c0K@ADO
</package> /;clxtus
c4Wl^E8
</xwork> ?{rpzrc!*
cbaa*qoU
$i]G'fj
AtYqD<hl:
.-4]FGg3
iWp
6^g
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 S\R5SRE
+
[~)a4#
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。 fe8}2#<o
2 pmqP-pKd
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 UWo*%&J
GvI8W)d3,R
PB?92py&
S?<hs,
B<\HK:%{
我写的一个用于分页的类,用了泛型了,hoho ^\C Fke=
gi #dSd1\&
java代码: I#PhzGC@
$L"h|>b\o
(C.<H6]=
package com.intokr.util; #6*20w_u
iOJ5KXrAO
import java.util.List; k keDt+^
ODNZLCB~t
/** gAr=fq-|
* 用于分页的类<br> ]8/g[Ii
* 可以用于传递查询的结果也可以用于传送查询的参数<br> 0,5)L\{
R
* -OXC;y
* @version 0.01 TX).*%f[r
* @author cheng PnZC
I!Mw
*/ `lA_knS
public class Paginator<E> { :JIJ!Xn)
privateint count = 0; // 总记录数 0)rayzv
privateint p = 1; // 页编号 bYBE h n
privateint num = 20; // 每页的记录数 $Ts;o
privateList<E> results = null; // 结果 i|[**P
],s{%a5wC
/** sf"vi i,1A
* 结果总数 t-Uo
*/ #\Zr$?t|V
publicint getCount(){ eI,H
return count; 2{<o1x,Ym
} y}1Pc*
*-(8Z>9
publicvoid setCount(int count){ 6{!Cx9V
this.count = count; DM,)nh6'
} kgh0
s;cGf+
/** K5^`,}Q^
* 本结果所在的页码,从1开始 "p]!="\
* 7~Z(dTdSG
* @return Returns the pageNo. (0E<Fz
V
*/ 9DdR"r'7
publicint getP(){ nh*6`5yj
return p; ksf6O$
} !<>*|a
eZ BC@y
/** \,ne7G21j
* if(p<=0) p=1 0*E_D
* Q^bYx (r5w
* @param p J`[gE`d
*/ 83J63Xa
publicvoid setP(int p){ 28qlp>U
if(p <= 0) {krBAz&
p = 1; "
v<O)1QT
this.p = p; @FZbp
} ^.9DfA0
?j&ZzK'#^
/** |A\o
* 每页记录数量 C5g9Gg
*/ !
(Q[[M
publicint getNum(){ $0k7W?tu
return num; lffw
"
} X;n09 L`CB
1,P\dGmu
/** Y#QXvo%
* if(num<1) num=1 }bSDhMV;
*/ YSrjg|k*
publicvoid setNum(int num){ &\%\"Zh
if(num < 1) ""A6n{4
num = 1; [bw1!X3
this.num = num; O?ODfO+>
} g(9kc<`3'D
$[Q;{Q
/** 67XUhnE
* 获得总页数 JIIc4fyy8s
*/ hpgOsF9Lh
publicint getPageNum(){ <4n"LJ9
return(count - 1) / num + 1; 6_:I~TTX
} Fv*Et-8tN5
e_"m\e#N
/** $01csj
* 获得本页的开始编号,为 (p-1)*num+1 &u~Pp=kv
*/ y)"rh /;
publicint getStart(){ #0PZa$kM(o
return(p - 1) * num + 1; n
=WH=:&
} 2Z5_@Y
)|_L?q#w!'
/** a?yU;IKJ
* @return Returns the results. r.lHlHl
*/ Wm}gnNwA
publicList<E> getResults(){ !9.FI{W
return results; Ii&p v
} {,u})U2
*nYg-)
public void setResults(List<E> results){ "7'P Lo3O
this.results = results; s/B_
} :d pwr9)
!FD d5CS
public String toString(){ cK >^8T^
StringBuilder buff = new StringBuilder 684|Uuf7
R$+p4@?S
(); }LeS3\+UHl
buff.append("{"); :t<