Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 Vg(p_k45`
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 U ;4;>
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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 HDo=W qG
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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 2}{[J
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分页支持类: M~sP|Ha"+
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java代码: +'e3YF+'
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package com.javaeye.common.util; -mZ{.\9
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import java.util.List; 7
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publicclass PaginationSupport { 'bef3P9`
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publicfinalstaticint PAGESIZE = 30; . Vq_O
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privateint pageSize = PAGESIZE; <>1*1%m
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privateList items; Bsz;GnD|r
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privateint totalCount; b~G|Bhxa
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privateint[] indexes = newint[0]; TLzcQ |
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privateint startIndex = 0; Kib?JRYt
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public PaginationSupport(List items, int qoD
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totalCount){ 1<9m^9_ro
setPageSize(PAGESIZE); LYiz:cQh
setTotalCount(totalCount); `!T6#6h
setItems(items); {Q~A;t
setStartIndex(0); ].w$b)G
} z[, `
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public PaginationSupport(List items, int 4~r=[|(aY
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totalCount, int startIndex){ 4a~9?}V:
setPageSize(PAGESIZE); fx4X!(w!B
setTotalCount(totalCount); &"svt2
setItems(items); dQFx]p3L
setStartIndex(startIndex); T+/Gz'
} - r82'3]
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public PaginationSupport(List items, int K`1\3J)
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totalCount, int pageSize, int startIndex){ B6Tn8@O
setPageSize(pageSize); UIv
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setTotalCount(totalCount); 'x10\Q65[
setItems(items); Z5{M_^
setStartIndex(startIndex); dDk<J;~jGJ
} F3a"SKMW
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publicList getItems(){ Fx0<!_tY-
return items; r,b-c
} L*VGdZ
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publicvoid setItems(List items){ 9W7H",wR
this.items = items; mvxg|<
} S*CRVs
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publicint getPageSize(){ zn3i2MWS
return pageSize; 66%kq[
} _W*3FH
#tBbvs+%
publicvoid setPageSize(int pageSize){ PHD$E s
this.pageSize = pageSize; .x1EdfHed/
} YKUs>tQ!
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publicint getTotalCount(){ ou-5iH?
return totalCount; QkzPzbF"
} `^afbW
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publicvoid setTotalCount(int totalCount){ $X-,6*
if(totalCount > 0){ Qo{^jDe,c*
this.totalCount = totalCount; 4F8`5)RM
int count = totalCount / d|6*1hby
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pageSize; ^ tm,gh
if(totalCount % pageSize > 0) ,)Z^b$H]
count++; ;nv4lxm
indexes = newint[count]; dmrM %a}W-
for(int i = 0; i < count; i++){ #!y|cP~;I
indexes = pageSize * J/wot,j^
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i; Mk[_yqoCO
} *+qXXCA
}else{ vC J
this.totalCount = 0; **0Y*Ax@
} Nc]oAY
} qdj,Qz9ly
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publicint[] getIndexes(){ <h7C_^L10\
return indexes; +\.gd L)
} S]{K^Q),
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publicvoid setIndexes(int[] indexes){ GXRK+RHuBi
this.indexes = indexes; |n~,$
} U#,2et6
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publicint getStartIndex(){ )Cyrs~
return startIndex; N9:xtrJ]_J
} Z:9"7^+
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publicvoid setStartIndex(int startIndex){ +l&ZN\@0X
if(totalCount <= 0) ]eP&r?B
this.startIndex = 0; m]Z&
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elseif(startIndex >= totalCount) tX Z5oG7
this.startIndex = indexes 7PP76$
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[indexes.length - 1]; }3^t,>I=,6
elseif(startIndex < 0) ~XQN4Tv-
this.startIndex = 0; ,T jd
else{ i+T$&$b
this.startIndex = indexes $xlI"-(
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[startIndex / pageSize]; %,-vmqr
} eH=lX9
} $0sUh]7y
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publicint getNextIndex(){ 0D:J d6\
int nextIndex = getStartIndex() + j$A~3O<e"
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pageSize; 3(}HD*{E[@
if(nextIndex >= totalCount) % nP13V]
return getStartIndex(); +;pdG[N
else lJu2}XRiU
return nextIndex; :kflq
} VL&E2^*E
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publicint getPreviousIndex(){ !YsLx[+
int previousIndex = getStartIndex() - $
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pageSize; *ukugg.
if(previousIndex < 0) C B=H1+
return0; FSIV\ u
else C8DZ:3E$c
return previousIndex; PDzVXLpC
} ;:hyW,J
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} 0^5SL/2
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抽象业务类 '|G_C%,B
java代码: BPIp3i
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/** x0?8AG%
* Created on 2005-7-12 ; mu9;ixZ
*/ c&e?_@}|
package com.javaeye.common.business; W0K&mBu
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import java.io.Serializable; Uz>5!_
import java.util.List; ]tanvJG}'
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import org.hibernate.Criteria; #^"\WG7{
import org.hibernate.HibernateException; dMp7 ,{FhF
import org.hibernate.Session; (?72 vCc
import org.hibernate.criterion.DetachedCriteria; 5^t68
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import org.hibernate.criterion.Projections; sf2_x>U1
import {W62%>v
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org.springframework.orm.hibernate3.HibernateCallback; $h`?l$jC(@
import
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org.springframework.orm.hibernate3.support.HibernateDaoS o) `zb?
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upport; !Ui3}
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@
import com.javaeye.common.util.PaginationSupport; '""qMRCm
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public abstract class AbstractManager extends R4"["T+L`
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HibernateDaoSupport { {6!Mf+Xq
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privateboolean cacheQueries = false; ]F r+cP
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privateString queryCacheRegion; zO<EbqNe!
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publicvoid setCacheQueries(boolean
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cacheQueries){ 8c\mm 0n
this.cacheQueries = cacheQueries;
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} #IDDKUE
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publicvoid setQueryCacheRegion(String *r!1K!c
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queryCacheRegion){ ;TD<\1HJT=
this.queryCacheRegion = +V4BJ/H
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queryCacheRegion; |j&u2DM~#m
} BP6;dF5E
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publicvoid save(finalObject entity){ eC%.xu^
getHibernateTemplate().save(entity); '\H {Y[
} 9Xmb_@7b}
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publicvoid persist(finalObject entity){ "Nj(0&
getHibernateTemplate().save(entity); E,JDO d}
} "tBdz V
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publicvoid update(finalObject entity){ lSC3m=4g
getHibernateTemplate().update(entity); [Maon.t!l
} zL5r8mD3
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publicvoid delete(finalObject entity){ /xJ,nwp7
getHibernateTemplate().delete(entity); Gy.<gyK9
} T5)Xl 'Q
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publicObject load(finalClass entity, g2^7PtJg
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finalSerializable id){ qEX2K^y'4"
return getHibernateTemplate().load - y{*U1[
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(entity, id); "zc@(OA[z
} -20o%t
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publicObject get(finalClass entity, ,*Y*ov23aQ
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finalSerializable id){ HAEgR
return getHibernateTemplate().get *>V6KW
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(entity, id); J5)e 7
} Yd~K\tX:n
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publicList findAll(finalClass entity){ %P0dY:L~
return getHibernateTemplate().find("from "5 PP<A,F(
^ 'FC.
" + entity.getName()); <Q/^[
} >&TSz5Q
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publicList findByNamedQuery(finalString GK)3a 9;
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namedQuery){ au9r)]p-
return getHibernateTemplate 0 lXV+lj
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().findByNamedQuery(namedQuery); [q cT?h
} tPP nW
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publicList findByNamedQuery(finalString query, "Ol;0>$
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finalObject parameter){ N[^%|
return getHibernateTemplate z{d] ,M
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().findByNamedQuery(query, parameter); 'G>Ejh@t
} uYIw ?fXy
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publicList findByNamedQuery(finalString query, GC66n1- X
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finalObject[] parameters){ vVc:[i
return getHibernateTemplate - >n<9
jec03wH_0
().findByNamedQuery(query, parameters); &UP@Sr0D7
} O}NR{B0B3&
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publicList find(finalString query){ 583ej2HPg
return getHibernateTemplate().find to[EA6J8l
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(query); MVjc.^
} V:6#IL
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publicList find(finalString query, finalObject b;]'Bo0K
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parameter){ 1]A%lud4
return getHibernateTemplate().find *0 i
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(query, parameter); f<xF+wE
} @_Aqk{3
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public PaginationSupport findPageByCriteria 5U|f"3&8
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(final DetachedCriteria detachedCriteria){ Xa*52Q`_
return findPageByCriteria ]O<Yr'
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); NTXT0:
} }n6BI}n
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public PaginationSupport findPageByCriteria pTGq4v@6x
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(final DetachedCriteria detachedCriteria, finalint < t>N(e
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startIndex){ ;Bcf~[ErM
return findPageByCriteria '0H+ 2
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(detachedCriteria, PaginationSupport.PAGESIZE, mt fDl;/D
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startIndex); n.$<D[@
} UbC)XiO
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public PaginationSupport findPageByCriteria /,Ln)?eD
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(final DetachedCriteria detachedCriteria, finalint V QPq+78
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pageSize, Q;m
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finalint startIndex){ F__DPEAc_
return(PaginationSupport) WRVKh
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getHibernateTemplate().execute(new HibernateCallback(){ ,>{4*PM(
publicObject doInHibernate c1|o^ eZ
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(Session session)throws HibernateException { k]R O=/ ?M
Criteria criteria = !!2~lG<]
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detachedCriteria.getExecutableCriteria(session); of+$TKQNpN
int totalCount = >GT0x
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((Integer) criteria.setProjection(Projections.rowCount px4Z
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()).uniqueResult()).intValue(); jq.@<<j|$
criteria.setProjection ;-*4 (3lu
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(null); LYWQqxB
List items = }{iR+MX
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criteria.setFirstResult(startIndex).setMaxResults C,tlp
]NTHit^EX
(pageSize).list(); f$2lq4P{
PaginationSupport ps = D KK200j
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new PaginationSupport(items, totalCount, pageSize, <LBMth
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startIndex); +BzKO >
return ps; NKGo E/
} D#(A?oN
}, true); 'J!P:.=a>
} sGdt)
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public List findAllByCriteria(final OmU.9PDg-
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DetachedCriteria detachedCriteria){ <&H.pN1_
return(List) getHibernateTemplate 0Fbq/63
vtL)
().execute(new HibernateCallback(){ F+hsIsQ
publicObject doInHibernate 7RdL/21K
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(Session session)throws HibernateException { VJ;'$SYx
Criteria criteria = W9eR3q
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detachedCriteria.getExecutableCriteria(session); ]&}?J:+?0E
return criteria.list(); P_b00",S
} )Xg#x:
}, true); BJW;A>@Pj
} v[Ar{t&
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public int getCountByCriteria(final &3u*
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DetachedCriteria detachedCriteria){ kP[ Y
Integer count = (Integer) N|7._AR2
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getHibernateTemplate().execute(new HibernateCallback(){ /]+t$K\cBq
publicObject doInHibernate :j9;P7&"?
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(Session session)throws HibernateException { 2RM0ca_F
Criteria criteria = {a(YV\^y|H
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detachedCriteria.getExecutableCriteria(session); (_-zm)F7
return Rjh/M`|
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criteria.setProjection(Projections.rowCount =&}dP%3LC)
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()).uniqueResult(); ;PLby]=O
} bLf }U9
}, true); r--"JO%2
return count.intValue(); !JrVh$K
} [kC-g @
} s6KZV@1
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用户在web层构造查询条件detachedCriteria,和可选的 1[B?nk
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 ]LP&v3
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PaginationSupport的实例ps。 x2K.5q>
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ps.getItems()得到已分页好的结果集 <L5[#V_
ps.getIndexes()得到分页索引的数组 2Uk$9s
ps.getTotalCount()得到总结果数 Ym!Ia&n
ps.getStartIndex()当前分页索引 |yQ3H)qB#
ps.getNextIndex()下一页索引 <EpP;
ps.getPreviousIndex()上一页索引 *4+;Ey
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 \.Q"fd?a_D
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,尤其是上面的示例代码,让我着实觉得该对我原来的分页查询做 ^V>sNR
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一下代码重构了。 G?8,&jP~T
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我把原本我的做法也提供出来供大家讨论吧: QbS w<V
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首先,为了实现分页查询,我封装了一个Page类: aA0aW=R
java代码: &.Yh_
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/*Created on 2005-4-14*/ :9K5zD
package org.flyware.util.page; 875V{fvPBU
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/** j1<@*W&b
* @author Joa ,?i#NN5p
* 0nA17^W
*/ 0$* z
publicclass Page { 1>l{c
lusINILc
/** imply if the page has previous page */ J&Le*R'
privateboolean hasPrePage; 3P'.)=}
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/** imply if the page has next page */ YceiP,!4?v
privateboolean hasNextPage; 2{**bArV
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/** the number of every page */ ~])\xC
privateint everyPage; [#uX{!q'
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/** the total page number */ QT\S>}
privateint totalPage; ToDN^qE+
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/** the number of current page */ Lj({
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privateint currentPage; Bn47O~
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/** the begin index of the records by the current Vx-HW;,
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query */ :NS;y-{^^y
privateint beginIndex; 5GT,:0
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/** The default constructor */ BI,K?D&W-
public Page(){ '-gk))u>)
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} +JBhw4et;.
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/** construct the page by everyPage HC}D<FX|
* @param everyPage 8~\Fpz|Og
* */ @+B
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public Page(int everyPage){ U:gE:t f
this.everyPage = everyPage; U-X
} XC0G5rtB
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/** The whole constructor */ 6i%LM`8GEk
public Page(boolean hasPrePage, boolean hasNextPage, <w.V !"!
@l>\vs<
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int everyPage, int totalPage, $:/y5zi
int currentPage, int beginIndex){ X1#D}
this.hasPrePage = hasPrePage; U|-4*l9Ed
this.hasNextPage = hasNextPage; m!N_TOl-^
this.everyPage = everyPage; m{(D*Vuqd
this.totalPage = totalPage; Y\sLwLLlG
this.currentPage = currentPage; .l !:|Fd
this.beginIndex = beginIndex; hH )jX`Ta
} (3c,;koRR
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/** r"Pj,}$A
* @return ZUAWSJ,s
* Returns the beginIndex. 7b:oz3 ?PI
*/ =u${2=
publicint getBeginIndex(){ =n9adq
return beginIndex; Nd^9.6,JU
} cJj0`@0f
@*%Q,$
/** RyIr_:&-~
* @param beginIndex 91mXv Q:u
* The beginIndex to set. Qaq{UW
*/ }_@cqx:n^
publicvoid setBeginIndex(int beginIndex){ [UR+G8X21m
this.beginIndex = beginIndex; f==o
} 1K09iB
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/** C[n,j#Mvje
* @return dZ`nv[]k~
* Returns the currentPage. {BY`Wu:w
*/ h8u(lIRHQ
publicint getCurrentPage(){ 5(u7b
return currentPage; [3t
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} +CX2W('
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/** IOvYvFUUJ
* @param currentPage :NA cad
* The currentPage to set. ;T-i+_
*/ j05ahquI
publicvoid setCurrentPage(int currentPage){ e0(loWq]
this.currentPage = currentPage; V<:kS
} \EUc17
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/** _o' jy^
* @return 0*B_$E06
* Returns the everyPage. uhQ3
*/ rS>njG;R
publicint getEveryPage(){
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return everyPage; 9 n|H%AC
} K )KE0/n
Y\dK-M{$
/** 3ZC to[Y
* @param everyPage P,xayy
* The everyPage to set. h9>~?1$lz
*/ -
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publicvoid setEveryPage(int everyPage){ 7:mM`0g!
this.everyPage = everyPage; PKwHq<vAsB
} qNC.|R
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/** vb5tyY0c
* @return rQj.W6w=
* Returns the hasNextPage. Ju)2J?Xs5
*/ 31Zl"-<#-
publicboolean getHasNextPage(){ 6LNm>O
return hasNextPage; TcO@q ]+S
} i. `S0
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/** ]Ny. gu
* @param hasNextPage 7! <cU
* The hasNextPage to set. /_o1b_1U
*/ !_l W#feR
publicvoid setHasNextPage(boolean hasNextPage){ i?4vdL8M
this.hasNextPage = hasNextPage; So bK<6
} #E{OOcM
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/** }4A+J"M4y
* @return PO<4rT+B
* Returns the hasPrePage. Hd2Sou4-j
*/ q:J,xC_sF(
publicboolean getHasPrePage(){ @"'1"$
return hasPrePage; kTc'k
} ,t*#o&+
cXE42MM
/** 'WxcA)z0cQ
* @param hasPrePage 4SY]Q[
* The hasPrePage to set. ;u!>( QQ
*/ H5^'J`0\
publicvoid setHasPrePage(boolean hasPrePage){ ]*ZL>fuD|
this.hasPrePage = hasPrePage; 42ttmN1F
} 9_5Fl,u
z
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/** {p
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* @return Returns the totalPage. hgfCM
* )z2Tm4>iql
*/ $-jj%x\}
publicint getTotalPage(){ `:-{8Vo7
return totalPage;
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} ?`,Xb.NA$K
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/** ;W'y^jp]"
* @param totalPage najd~%?Rs
* The totalPage to set. g=o)=sQd
*/ 2Z\6xb|u
publicvoid setTotalPage(int totalPage){ -81usu&NH
this.totalPage = totalPage; D(@#Gd\Z@
} 1EyM,$On
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} =HQH;c"
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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 H}dsd=yO
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个PageUtil,负责对Page对象进行构造: 5m=3{lBi
java代码: CsQ}eW8uEf
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/*Created on 2005-4-14*/ UqsVqi
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package org.flyware.util.page; O-U_Zx0zd
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import org.apache.commons.logging.Log; w`CGDF\Oo
import org.apache.commons.logging.LogFactory; t(\d;ybyx
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y
/** [`6|~E"F
* @author Joa J2v=b?NE
* j_o6+Rk
*/ Q|"{<2"]U0
publicclass PageUtil { n^UrHHOL
kbI:}b7H
privatestaticfinal Log logger = LogFactory.getLog s~Ni\SF
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(PageUtil.class); /=FQ{tLr
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/** )^|zuYzN
* Use the origin page to create a new page :05>~bn>pC
* @param page _o8il3
* @param totalRecords cW/RH.N
* @return DCACj-f
*/ |FS79Bv
publicstatic Page createPage(Page page, int Ki,]*-XO
Vv
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totalRecords){ ([qw#!;w;
return createPage(page.getEveryPage(), JY"<b6C^
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page.getCurrentPage(), totalRecords); Y`uL4)hR5
} $"!"=v%B
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/** CKNC"Y*X
* the basic page utils not including exception JY(_}AAu
'{5|[
handler OHdCt
* @param everyPage Dr^#e
* @param currentPage od"Oq?~/t
* @param totalRecords +Tf ,2?O
* @return page 5)wz `OS
*/ t,]r%
publicstatic Page createPage(int everyPage, int .,)NDG4Q
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currentPage, int totalRecords){ s_N?Y)lS+(
everyPage = getEveryPage(everyPage); ;dPyhR
currentPage = getCurrentPage(currentPage); f\nF2rlu
int beginIndex = getBeginIndex(everyPage, XkHO =
"~:o#~F6
currentPage); 9fp1*d
int totalPage = getTotalPage(everyPage, 'JsP9>)
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totalRecords); 6+b!|`?l+
boolean hasNextPage = hasNextPage(currentPage, Y,RBTH
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totalPage); '2vZ%C$
boolean hasPrePage = hasPrePage(currentPage); x{`>Il
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returnnew Page(hasPrePage, hasNextPage, R3`!Xj#&M
everyPage, totalPage, hF"yxucj$
currentPage, 9+)5 #!0
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beginIndex); (, Il>cR4
} +@ga
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privatestaticint getEveryPage(int everyPage){ 9YS &RBJu
return everyPage == 0 ? 10 : everyPage; Nih8(pbe
} p}$VBl$'
%e.tAl"!$
privatestaticint getCurrentPage(int currentPage){ \R#]}g0!
return currentPage == 0 ? 1 : currentPage; ln-+=jk
} ' te4mY}
KP`{ UD)
privatestaticint getBeginIndex(int everyPage, int I&^B?"Y
3=@94i
currentPage){ >0z(+}]3z
return(currentPage - 1) * everyPage; H,bYzWsrPo
} |dcRDOTe
Sz|;wsF{
privatestaticint getTotalPage(int everyPage, int \_;zm+ <{
Z+!._uA
totalRecords){ 6}zargu(;
int totalPage = 0; .\ K0+b;
{XAm3's
if(totalRecords % everyPage == 0) T{-<G13
totalPage = totalRecords / everyPage; H/n3il_-I
else *Y8nea^$
totalPage = totalRecords / everyPage + 1 ; (!`TO{ !6P
<2@V$$Qg.~
return totalPage; y,e#e`
} .21[3.bp/q
{}!`v%z
privatestaticboolean hasPrePage(int currentPage){ R+
#(\
return currentPage == 1 ? false : true; Wm_:1~
} s @\UZC
Q'xZ\t
privatestaticboolean hasNextPage(int currentPage, 's#"~<L^e
yzJ
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int totalPage){ #Duz|F+%
return currentPage == totalPage || totalPage == iv@ey-,<
$*a'[Qot#
0 ? false : true; S- @E
} do0;"O0
(
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~Iw7Xq E2
} GR6BpV7
Z#w@ /!"}T
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it?l! ~
"\0&1C(G
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 t0t" =(d
mhTi{t_fHM
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 kaybi 0
M;s r1C
做法如下: 2 VgFP3
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 n
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hbfTv;=z
的信息,和一个结果集List: ,|RS]I>X
java代码: ]!l]^/.
!e+ex"7
NJ"
d`
/*Created on 2005-6-13*/ YMGzO
package com.adt.bo; iBlZw%zKP
/*,hR >UG
import java.util.List; u!wR
<<a1a
import org.flyware.util.page.Page; =/_tQR~
eAvOT$
/**
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* @author Joa M3>c?,O)J
*/ yMz%s=rh
publicclass Result { 7&ty!PpD
osB8
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private Page page; ~cHpA;x9<^
b=Rw=K.
private List content; 6[cC1a3r:
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/** 7;]n+QRfm
* The default constructor .aJ\^Fx
*/ 3RSiu}
public Result(){ d"h*yH@
super(); Na6z1&wS
} x+1Cs$E;
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/** {& Pk$Q!
* The constructor using fields /3( a'o[
* Y`secUg
* @param page 0f"9wPC
* @param content #2&DDy)Bf
*/ bf#@YkE
public Result(Page page, List content){ V_)G=#6Dy
this.page = page; bLSZZfq
this.content = content; _tl
} p_ H;|m9
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/** D/& 8[Z/Cn
* @return Returns the content. Zq,[se'nh"
*/ 6R.%I{x'
publicList getContent(){ rt5FecX\
return content; e7T}*Up
} O7]p `Xi8
+0{$J\s
/** 0[\^Y<ec
* @return Returns the page. HNFG:t9
*/ ,RP"m#l!\
public Page getPage(){ gL)l)}#
return page; c/K:`XP~
} p,(gv])ie
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/** J(0E'o{ug
* @param content [:vH_(|
* The content to set. F_<n8U:Y
*/ *9XKkR<r
public void setContent(List content){ pJnT \~o
this.content = content; bSG}I|
} \B72 #NR
g?TPRr~$9
/** xZMQ+OW2i
* @param page (pDu
* The page to set. d*}dM"
*/ vS@;D7ep
publicvoid setPage(Page page){ "7G>
this.page = page; !Dc|g~km\
} *VP-fyJp
} :!'!V>#g
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<6!;mb
;cX
%>)HAx `
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2. 编写业务逻辑接口,并实现它(UserManager, t9QnEP'
>e'Hz (~'/
UserManagerImpl) 88]4GVi
java代码: ?KB+2]7m6
cs-wqxTX[$
fRt`]o:Om
/*Created on 2005-7-15*/ [.
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package com.adt.service; ,
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import net.sf.hibernate.HibernateException; O
,9,=2j
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import org.flyware.util.page.Page; w%3*T#tp
8@)4)+e
import com.adt.bo.Result; U8>M`e"D
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/** $2kZM4
* @author Joa D#.N)@\
*/ q{c/TRp7
publicinterface UserManager { !gyEw1Re7
i&di}x
public Result listUser(Page page)throws eI^Q!b8n
*LZB.84
HibernateException; ozCH1V{p
"0V8i%a
} U65a_dakk
iVUkM3
I'%\
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fZ6-ap,u
lQ{o[axT
java代码: yGs:3KI
O: J;zv\
J Yesk
/*Created on 2005-7-15*/ 5*#3v:l/9
package com.adt.service.impl; &OXWD]5$6
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import java.util.List; d%(4s~y
M3EB=tU
import net.sf.hibernate.HibernateException; {[[j .)
aGx[?}=
import org.flyware.util.page.Page; *[ww;
import org.flyware.util.page.PageUtil; ~USU\dni
vw'BKi
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import com.adt.bo.Result; tB<2mjg
import com.adt.dao.UserDAO; .~C[D
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import com.adt.exception.ObjectNotFoundException; },& =r= B
import com.adt.service.UserManager; $j"TPkW{M
p+y2w{{
/** W*!u_]K>
* @author Joa YsBOh{Ml
*/ }|-Yd"$
publicclass UserManagerImpl implements UserManager { ][[\!og
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private UserDAO userDAO; VUbg{Rb)
B4/\RC2
/** wF.S ,|
* @param userDAO The userDAO to set. =JM !`[
*/ WvVf+|Km
publicvoid setUserDAO(UserDAO userDAO){ AZ'"Ua
this.userDAO = userDAO; "l7))>lL
} %{j)w{
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]ff5MY 36
/* (non-Javadoc) cq,8^o&
* @see com.adt.service.UserManager#listUser cpJ(77e
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(org.flyware.util.page.Page) bKb}VP
*/ =L F9im
public Result listUser(Page page)throws 4)OM58e}
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HibernateException, ObjectNotFoundException { 3w!,@=.q
int totalRecords = userDAO.getUserCount(); O<}KrmUC~
if(totalRecords == 0) X ^\kI1
throw new ObjectNotFoundException 5.o{A#/NTl
&LM ^,xx}
("userNotExist"); TQiDbgFo
page = PageUtil.createPage(page, totalRecords); o?]g
List users = userDAO.getUserByPage(page); uHu (
returnnew Result(page, users); 1(*Pa
} 5IfyD ]<
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} oHvVZ
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其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 +:D90p$e
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询,接下来编写UserDAO的代码: l We1Q#
3. UserDAO 和 UserDAOImpl: }3xZ`vX[T
java代码: GJB=5nE
"JBTsQDj!
dLnu\bSF
/*Created on 2005-7-15*/ X GhV?
tA
package com.adt.dao; { kF"<W
hq[RU&\
import java.util.List; mok%TK
[ta3sEPjs
import org.flyware.util.page.Page; xOgUX6n
)?qH#>mD6
import net.sf.hibernate.HibernateException; , U?W
$Afw]F$
/** 0A.PfqYi
* @author Joa 8/16<yZ
*/ L^Q q[>
publicinterface UserDAO extends BaseDAO { F>!gwmn~
H6Qb]H.C
publicList getUserByName(String name)throws `*to(
)
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HibernateException; ( /):
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publicint getUserCount()throws HibernateException; eo~>|0A*V
;s(uaC3
publicList getUserByPage(Page page)throws G"._]3CPF
;p U=>
HibernateException; TA~YCj$
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} #FL\9RXy
,O[Maj/ch
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v7kR]HU[y
K0bh;I
java代码: 2*<'=*zaQ
(b}}'
LtDQgel"
/*Created on 2005-7-15*/ %C^%Oq_k
package com.adt.dao.impl; G>q16nS~KP
1G6MO
import java.util.List; <y30t[.E6
buv*qPO
import org.flyware.util.page.Page; "Nx3_mQ
y_Tc$g~
import net.sf.hibernate.HibernateException; }CyS_Tc
import net.sf.hibernate.Query; ju= +!nGUa
0-9.u`)#yu
import com.adt.dao.UserDAO; B,Gt6cUq
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/** ZX
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* @author Joa KOQ9K
*/ ,%a7sk<5k
public class UserDAOImpl extends BaseDAOHibernateImpl +uY)MExs2
nHB=*Mj DV
implements UserDAO { U.[?1:v
@^)aUOe
/* (non-Javadoc) ps*dO
* @see com.adt.dao.UserDAO#getUserByName %%w/;o!c
w|uO)/v
(java.lang.String) i(k]}Di:
*/ MGmUgc
publicList getUserByName(String name)throws l6C^,xU~IX
|=Mn~`9p
HibernateException { (Wm4JmX%
String querySentence = "FROM user in class g+-=/Ge
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com.adt.po.User WHERE user.name=:name"; 3N]
Query query = getSession().createQuery ]-D;t~
nnZ|oEF
(querySentence); ~
}<!ON;
query.setParameter("name", name); 7fOk]Yl[
return query.list(); J"x M[c2
} ~alC5|wCUQ
Z!qH L$
/* (non-Javadoc) $6c8<!B_
* @see com.adt.dao.UserDAO#getUserCount() E!eBQ[@
*/ KvM}g2"
publicint getUserCount()throws HibernateException { ;'B\l@U\
int count = 0; '~1uJ0H
String querySentence = "SELECT count(*) FROM osJ;"B36
#\[((y:q
user in class com.adt.po.User"; oM@X)6P_
Query query = getSession().createQuery gGiLw5o,
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(querySentence); -F+dRzxH
count = ((Integer)query.iterate().next +;}XWV
}- Jw"|^W
()).intValue(); jZm57{C#*?
return count; l+>&-lX'
} N|,6<|
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/* (non-Javadoc) E! i:h62
* @see com.adt.dao.UserDAO#getUserByPage Daa2.*
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(org.flyware.util.page.Page) LN8V&'>
*/ 9M)N2+hkZ
publicList getUserByPage(Page page)throws /;%[:x
ugM,wT&~Y
HibernateException { $Q[>v!!X
String querySentence = "FROM user in class M~/%V NX
ldJ:A*/M6
com.adt.po.User"; "e4hPY#
Query query = getSession().createQuery He4sP`&I
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(querySentence); *{]9e\DF
query.setFirstResult(page.getBeginIndex()) `hD\u@5Tw
.setMaxResults(page.getEveryPage()); DR`d^aBWQ
return query.list(); wn'_;0fg
} gJNp]I2R
hi>sDU<x
} W*q[f!@
F<y5zqGy@
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eD0Rv0BV^
0Ts[IHpg&E
至此,一个完整的分页程序完成。前台的只需要调用 -Bqn^ E
(mvAEN+y
userManager.listUser(page)即可得到一个Page对象和结果集对象 G[YbgG=9Y
PrIS L[@
的综合体,而传入的参数page对象则可以由前台传入,如果用 Z2Bl$ \
cH()Ze-B
webwork,甚至可以直接在配置文件中指定。 Q"UQv<
&~+lXNXF
下面给出一个webwork调用示例: *`:zSnu
java代码: u-zl- ?Ne
xf8C$|,
kfo, PrW`A
/*Created on 2005-6-17*/ 1"r6qYN!>
package com.adt.action.user; A L#"j62
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import java.util.List; Ed3 *fY
gqaENU>
import org.apache.commons.logging.Log; OLc/Vij;
import org.apache.commons.logging.LogFactory; n&=3Knbd@d
import org.flyware.util.page.Page; odPq<'V|AY
%+iJpRK)7
import com.adt.bo.Result; BzL>,um
import com.adt.service.UserService; ~Dw.3P:-
import com.opensymphony.xwork.Action; C+-xC~
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/** *<2+tI
* @author Joa (!Q^.C_m
*/ :qi"I;=6
publicclass ListUser implementsAction{ $-m`LF@
l6.z-Qw
privatestaticfinal Log logger = LogFactory.getLog ir<HC 'D[
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(ListUser.class); _eAZ_@
~/J:p5?L
private UserService userService; q9w6 6R
}E+}\&
private Page page; z#*w Na&@[
eN@V?G26K
privateList users; PuAcsYQhN
Y!9'Wf/^
/* +1Oi-$
2-
* (non-Javadoc) m/sAYF"
* `#hdb=3
* @see com.opensymphony.xwork.Action#execute() L2[|g~
*/ dI<s)!
publicString execute()throwsException{ 0"$Ui#r`
Result result = userService.listUser(page); c6cGl]FL
page = result.getPage(); "q4c[dna
users = result.getContent(); }zi:nSpON
return SUCCESS; b(dIl)Y4
:
} ]%m0PU#
.WA(X5
/** ZKyK#\v<
* @return Returns the page. =jjUwcl
*/ Fn*clx<
public Page getPage(){ ~M%r.WFpA
return page; Fxy-_%a
} gT*0WgB
u1O?`
/** XX",&cp02V
* @return Returns the users. "BZ6G`
*/ LX[J6YKR
publicList getUsers(){ ]Qe;+p9vU
return users; Lz2 AWqR
} -Y%#z'^-
@ 'rk[S}A
/** GEXT8f(7
* @param page ,# rl"
* The page to set. SeqnO.\
*/ O/$pT%D1x
publicvoid setPage(Page page){ b5_(Fv
this.page = page; &bBK#d*-u?
} "TA r\;[
:\x53-&hO4
/** :Eq=wbAw
* @param users /rN%y
* The users to set. Fyoy)y*
*/ VYI%U'9Q
publicvoid setUsers(List users){ x; 89lHy@e
this.users = users; "*|plB
} Es6b~#
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/** %m1k^
* @param userService 7
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* The userService to set. (nfra,'
*/ My0h9'K
publicvoid setUserService(UserService userService){ }2-<}m9}
this.userService = userService; {@1.2AWg
} Lzu;"#pw
} !xyO
Z W`
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Rq~\Yf+Pm
saQA:W;
V`?2g_4N
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, 4Waot
]8KAat~J
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 N r5
aU6]
~fB}v
么只需要: a(&!{Y1bt
java代码: ]uO 8
e|u|b
Bt4
X
<?xml version="1.0"?> :#v8K;C
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork b;K>Q!(|
"ut:\%39.
1.0//EN" "http://www.opensymphony.com/xwork/xwork- de]r9$D
mcAg,~"HB
1.0.dtd"> 4mSL*1j
w_|R.T\7
<xwork> |4//%Ll/
%:oyHlz%
<package name="user" extends="webwork- t]LCe\#
6r"uDV #0
interceptors"> 50%
|9D0?Y
l^4[;%*f#l
<!-- The default interceptor stack name ?n)r1m
z)"7qqA
--> g{wIdV
<default-interceptor-ref '(A)^K>+
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name="myDefaultWebStack"/> nB2AmS
ZK<kn8JJ
<action name="listUser" > ^fY`x,
9'F-D
class="com.adt.action.user.ListUser"> ?P4@U9i
<param Dt?O_Bdv[
^Cb7R/R3
name="page.everyPage">10</param> ?PORPv#
<result f2Frb
g/,fjM_
name="success">/user/user_list.jsp</result> 7><n e|%
</action> 6$[7t?u
=$601r
</package> s mub> V
u%?u`n2'
</xwork> 8>a/x ,
^c{}G<U^
I7b(fc-r
qQN&uBQ[
dq~p]h~,H
)BNm~sP
这样就可以通过配置文件和OGNL的共同作用来对page对象设置初值 d{+H|$L`
{V%ZOdg9
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。 m&o}qzC'y
UI|L;5
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 ,}F2l|x_
hH:7
p.i$[6M
I!lzOg4~
;SkC[;`J
我写的一个用于分页的类,用了泛型了,hoho lM Gz"cym
^zkTV_,cRp
java代码: 3=~"<f
l
5}
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package com.intokr.util; d_#\^!9
g6EdCG.V
import java.util.List; XPXC7_fV
!OM9aITv[
/** g.aNITjP
* 用于分页的类<br> 5P{dey!
* 可以用于传递查询的结果也可以用于传送查询的参数<br> \@nmM&7C!4
* qT#+DDEAL
* @version 0.01 zNRoFz.
* @author cheng
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*/ 6,M>' s,N
public class Paginator<E> { W]5kM~Q@
privateint count = 0; // 总记录数 #G{}Rd|!
privateint p = 1; // 页编号 C- ]H+p
privateint num = 20; // 每页的记录数 JGt4B
privateList<E> results = null; // 结果 f2[z)j7
M]!\X6<_
/** !Jb?rSJ.h
* 结果总数 kac@yQD
*/ 94I8~Jj4
publicint getCount(){ TveCy &
return count; '[JrP<~^o
} &q1(v3cOO
|Z6rP-
publicvoid setCount(int count){ $=iz&{9
this.count = count; W-=~Afy
} U6FM`w<
rS/Q
/** k<=.1cFh
* 本结果所在的页码,从1开始 AM##:4
* -Qo`UL.}
* @return Returns the pageNo. 0sVCTJ@
*/ Jjik~[<q:
publicint getP(){ ~CldqXeI
return p; '1ff| c!x9
} k]Y+C@g
h3aHCr E
/** 4PTHUyX
* if(p<=0) p=1 ?nrd$,
* kJy<vb~
* @param p *La*j3|:
*/ bjPI:j*XU
publicvoid setP(int p){ =Xm
[
if(p <= 0) dTyTj|"x{
p = 1; 6VolTy@(x
this.p = p; j9%u&
} sBS\S
=r+u!~%@''
/** Mp?Ev.
* 每页记录数量 `>rdn*B
*/ b'Z#RIb
publicint getNum(){ +
}(
return num; W6&".2
} x*i5g`jx
Mb3,!
/** h(d<':|
* if(num<1) num=1 vkE6e6,Qc
*/ :
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publicvoid setNum(int num){ y2\, L
if(num < 1) #E5#{bra
num = 1; *ky5SM(NR
this.num = num; S#!PDg
} h\C
/QHvwaW[
/** Y!i4P#4+q
* 获得总页数 Kx*;!3-V$
*/ 8iK>bp
publicint getPageNum(){ yXc/Nl%
return(count - 1) / num + 1; &kXf)xc<~
} )eY3[>`
S`K8e^]
/** [>;U1Wt
* 获得本页的开始编号,为 (p-1)*num+1 nEQw6q~je
*/ }_3<Q\j
publicint getStart(){ GpN tvo~
return(p - 1) * num + 1; LEc%BQx
} 65=i`!f
z^{VqC*o+
/** H~J#!3
* @return Returns the results. B2
Tp;)
*/ oVb6,Pn
publicList<E> getResults(){ PS`v3|d}}}
return results; ~7 C` a$
} [#)-F_S
-2K`:}\y&
public void setResults(List<E> results){ 'RTz*CSZ
this.results = results; )+N%!(ki
} 4B-v\3Ff
o9<jj> R;
public String toString(){ JDD(e_dw
StringBuilder buff = new StringBuilder P[8`]=
NL0X =i
(); JdfjOlEb
buff.append("{"); K
S,X$)9
buff.append("count:").append(count); Y=x]'3}^
buff.append(",p:").append(p); $vTU|o>|
buff.append(",nump:").append(num); 5bH@R@3 m
buff.append(",results:").append :a0qm.EN
].
IUQ*4t
(results); x>!#8?-h
buff.append("}"); +[V?3Gdb
return buff.toString(); fN?HF'7V
} 9%$4Ux*q
v /G,
} Qi w "x,
`V$i*{c:#
#QXB2x<*