Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 !:c_i,N
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 ijACfl{!:t
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据这一功能,我设计了通用的抽象Bean基类和分页类支持,代码来 N{#9gr3zi
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自于Quake Wang的javaeye-core包的相应类,然后又做了很多修改 d]vom@iI
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分页支持类: *:?XbtIK u
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java代码: _0o65?F
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package com.javaeye.common.util; 5}TTf2&Xo#
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import java.util.List; U;#G$
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publicclass PaginationSupport { %?Q<
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publicfinalstaticint PAGESIZE = 30; yG2rAG_G&
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privateint pageSize = PAGESIZE; w ufQyT`
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privateList items; 49=L9:
>02p,W6S>
privateint totalCount; yp]z@SYA@
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privateint[] indexes = newint[0]; g>QN9v})
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privateint startIndex = 0; {wD:!\5
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public PaginationSupport(List items, int DD}YbuO7
"a-;?S&
totalCount){ #giH`|#d
setPageSize(PAGESIZE); pP%9MSCi
setTotalCount(totalCount); <07]w$m/
setItems(items); Mtc -
setStartIndex(0); ]fSpG\yU
} e_}tK1XY
|3BxNFe`%
public PaginationSupport(List items, int xAr&sGMA
)JhB!P(
totalCount, int startIndex){ $!^C|,CS
setPageSize(PAGESIZE); +5Ju `Z
setTotalCount(totalCount); U$WGe >,
setItems(items); S8O,{
setStartIndex(startIndex); &aPR" X
} ]IH1_?HgP7
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public PaginationSupport(List items, int 8x-(7[#e<g
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totalCount, int pageSize, int startIndex){ ~9#'s'
setPageSize(pageSize); q4g)/x%nc
setTotalCount(totalCount); K%UjPzPWw
setItems(items); XB]>Z)
setStartIndex(startIndex); o|w
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} dEkAUH
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publicList getItems(){ ji<(}d~L*
return items; :mhO/Bx
} N]-skz<v
sF3@7~m4
publicvoid setItems(List items){ e.W <pI,
this.items = items; ,[<$X{9
} -/:K.SY,
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publicint getPageSize(){ KE-0/m4yJ
return pageSize; )hC3'B/[Y
} & jm1
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publicvoid setPageSize(int pageSize){ :i|Bz6Ht4
this.pageSize = pageSize; v8zO Y#?
} LtPaTe
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publicint getTotalCount(){ yq[.
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return totalCount; lYmxd8
} :<HLw.4O
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publicvoid setTotalCount(int totalCount){ 6{I6'+K~
if(totalCount > 0){ ;U#=H9_
this.totalCount = totalCount; ^oR
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int count = totalCount / 4'td6F
Awr(}){
pageSize; @"H7Q1Hg!*
if(totalCount % pageSize > 0) 7~);,#[ky
count++; Eqi;m,)
indexes = newint[count]; pG22Nx
for(int i = 0; i < count; i++){ JvNd'u)Z<
indexes = pageSize * @>&b&uj7T
x~F YG
i; 7=s0Pm
} #CcEI
}else{ r;p@T8k
this.totalCount = 0; o#WECs>
} (M<l}pl)
} gf}*}8D
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publicint[] getIndexes(){
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return indexes; Y#+Ws0wN
} uN1VkmtDO
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publicvoid setIndexes(int[] indexes){
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this.indexes = indexes; a^_W}gzzd
} wc-v]$DW
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publicint getStartIndex(){ (EjlnG}5l
return startIndex; -2'+GO7G
} CR;E*I${
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publicvoid setStartIndex(int startIndex){ E!uQ>'iq.
if(totalCount <= 0) D&i,`j
this.startIndex = 0; ) I(9qt>Y
elseif(startIndex >= totalCount) XA;f.u
this.startIndex = indexes HU$]o N
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[indexes.length - 1]; uG/'9C6Z
elseif(startIndex < 0) M Np4=R
this.startIndex = 0; AMASh*
else{ JSID@
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this.startIndex = indexes CugZ!>;^
?9>wG7cps7
[startIndex / pageSize]; X&i;WI
} PjXiYc&
} OUFy=5(%:
5>UQ 3hWo
publicint getNextIndex(){ %Y"pVBc
int nextIndex = getStartIndex() + ?uU_N$x
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pageSize; l]j;0 i
if(nextIndex >= totalCount) 6uKP
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return getStartIndex(); # ,97 ]
else R_>.O?U4
return nextIndex; hwA&SS
} KP
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publicint getPreviousIndex(){ q*tGlM@R?
int previousIndex = getStartIndex() - Ep:hObWG)
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pageSize; %yd(=%)fMB
if(previousIndex < 0) A&M(a
return0; Z1:<i*6>D
else ;?q}98-2
return previousIndex; <
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} \3"B$Sp|=
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} kR:kn:
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抽象业务类 DuT6Od/f
java代码: sv!v`zh
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/** o!U(=:*b
* Created on 2005-7-12 Zu~w:uNmU
*/ U_;="y
package com.javaeye.common.business; -7'|&zP
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import java.io.Serializable; cB36w$n8
import java.util.List; "K$c 9Z8
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import org.hibernate.Criteria; X6_
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import org.hibernate.HibernateException; uA;#*eiA/
import org.hibernate.Session; R MOs1<D
import org.hibernate.criterion.DetachedCriteria; VW*?(,#j{
import org.hibernate.criterion.Projections; l9OpaOVfJ
import Dsn=fht
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org.springframework.orm.hibernate3.HibernateCallback; }0Uh<v@
import /8nUecr
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org.springframework.orm.hibernate3.support.HibernateDaoS _0FMwC#DY
6\jbSe
upport; D$>&K&
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import com.javaeye.common.util.PaginationSupport; iH@u3[w
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public abstract class AbstractManager extends AzSu_
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HibernateDaoSupport { %NJ0Y(:9(
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privateboolean cacheQueries = false; GAZRQ
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privateString queryCacheRegion; (5,x5l]-N
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publicvoid setCacheQueries(boolean S'W,AkT
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cacheQueries){ IR$d?\O3
this.cacheQueries = cacheQueries; hdcB*j?4
} >HRNB&]LdP
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publicvoid setQueryCacheRegion(String =:xX~,qmv
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queryCacheRegion){ BDzAmrO<
this.queryCacheRegion = B|yz~wuS
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queryCacheRegion; Tx]p4wY:D
} w{|`F>f9
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publicvoid save(finalObject entity){ mqHH1}
getHibernateTemplate().save(entity); WVhQ?2@ }
} /5z,G r
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publicvoid persist(finalObject entity){ %3"3V1
getHibernateTemplate().save(entity); m.
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} F$jy~W_
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publicvoid update(finalObject entity){ Mis B&Ok`k
getHibernateTemplate().update(entity); i$$h6P#
} 5Phsh
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publicvoid delete(finalObject entity){ 7I#C[:7x
getHibernateTemplate().delete(entity); ?e4H{Y/M
} @: =vK?8L
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publicObject load(finalClass entity, maY.Z<lN
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finalSerializable id){ KK1?!7
return getHibernateTemplate().load a^|9rho<
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(entity, id); b_6cK#
} 7FyE?
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publicObject get(finalClass entity, MffCk!]
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finalSerializable id){ @1&"S7@}u
return getHibernateTemplate().get ?u?mSO/
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(entity, id); m;hp1VO)
} 7&wxnxSk^
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publicList findAll(finalClass entity){ )8rF'pxI
return getHibernateTemplate().find("from o _l_Yi
3 yb]d5:U
" + entity.getName()); ZzTkEz >
} zh0T3U0D
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publicList findByNamedQuery(finalString F[%k;aJ
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namedQuery){ `''y,{Fs
return getHibernateTemplate "4Q_F3?_`
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().findByNamedQuery(namedQuery); L@=$0p41;
} #Y3-P
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publicList findByNamedQuery(finalString query, kZ)}tA7j
(~{Y}n]s
finalObject parameter){ 94dd )/a
return getHibernateTemplate 6|
o S 5
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().findByNamedQuery(query, parameter); H25Qx;(dTk
} CueC![pj
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publicList findByNamedQuery(finalString query, SiaW; ks
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finalObject[] parameters){ .K(9=yh
return getHibernateTemplate vY|YqWt
yEbo`/ ]b
().findByNamedQuery(query, parameters); %HtgZeY
} .U@u |
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publicList find(finalString query){
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return getHibernateTemplate().find m%[/w wL
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(query); x3`JC&hF,q
} %kop's&?C
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publicList find(finalString query, finalObject z,E`+a;
",vK~m2W_
parameter){ z80FMulO
return getHibernateTemplate().find .zt&HI.F
vk
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(query, parameter); ^xNzppz`]C
} 3h=kn@I
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public PaginationSupport findPageByCriteria Jq(;BJ90R
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(final DetachedCriteria detachedCriteria){ Z'2AsT
return findPageByCriteria +^esL9RG:
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); Ri_2@U-
} ~CV.Ci.dG
ru 9@|FgAE
public PaginationSupport findPageByCriteria (>ze{T|
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(final DetachedCriteria detachedCriteria, finalint P*7G?
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startIndex){ 5psJv|Zo]
return findPageByCriteria BgUp~zdo
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(detachedCriteria, PaginationSupport.PAGESIZE, (tVT&eO
MI(#~\Y~P
startIndex); *P7/ry^<F
} j\bp#+
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public PaginationSupport findPageByCriteria G,$nq4
b-#{O=B
(final DetachedCriteria detachedCriteria, finalint uF}dEDB|;
S ;rd0+J
pageSize, %~M* <pN
finalint startIndex){ ;ZAwf0~
return(PaginationSupport) DW9MX`!Xc
*<67h*|)
getHibernateTemplate().execute(new HibernateCallback(){ >2pxl(i
publicObject doInHibernate -2[4 @
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(Session session)throws HibernateException { S#8)N`
Criteria criteria = D QxuV1
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detachedCriteria.getExecutableCriteria(session); 7rRI-wZ
int totalCount = f"j9C%'*
1_f+!
ns#
((Integer) criteria.setProjection(Projections.rowCount Udtz zka
ElB[k<
()).uniqueResult()).intValue(); c"lwFr9x7
criteria.setProjection T"za|Fo
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(null); i6n,N)%H
List items = j|Vl\Z&o)
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criteria.setFirstResult(startIndex).setMaxResults kw2yb
M$@~|pQ<
(pageSize).list(); )LKJfoo
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PaginationSupport ps = cf"&22TQ+Z
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new PaginationSupport(items, totalCount, pageSize, ?K:\WW
0ElEaH1z
startIndex); -`\^_nVC
return ps; {'M/wT)FeC
} p2rT0gu!
}, true); GeY!f/yQ<
} P%l?C?L
PcT]
public List findAllByCriteria(final `f&::>5tD
a*X{hU9P
DetachedCriteria detachedCriteria){ g3[-[G^5
return(List) getHibernateTemplate ([rn.b]
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().execute(new HibernateCallback(){ I)` +:+P
publicObject doInHibernate ^VMCs/g6
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(Session session)throws HibernateException { TS+jDs
Criteria criteria = o jxK8_kl
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detachedCriteria.getExecutableCriteria(session); Yu)GV7\2
return criteria.list(); {X?1}5ry
} !<~.>5UQ
}, true); +
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} :ZB.I(v
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public int getCountByCriteria(final ,qp8Rg|3j
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DetachedCriteria detachedCriteria){ ."BXA8c;A
Integer count = (Integer) juF=ZW%i
5&EBUl}
getHibernateTemplate().execute(new HibernateCallback(){ 3$YbEl@#
publicObject doInHibernate +VW8{=$
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(Session session)throws HibernateException { I|&DXF
Criteria criteria = T|BlFJ0"
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detachedCriteria.getExecutableCriteria(session); 7"aN7Q+EbI
return &gS-.{w "
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criteria.setProjection(Projections.rowCount l"dXL"h
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()).uniqueResult(); ,@;|+C
} 4<UAT|L^`
}, true);
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return count.intValue(); &53,8r
} $#5'c+0
} aL&egM*
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用户在web层构造查询条件detachedCriteria,和可选的 1U/9=b
qP;1LAX
startIndex,调用业务bean的相应findByCriteria方法,返回一个 RZ{O6~VH
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PaginationSupport的实例ps。 iVeH\a
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ps.getItems()得到已分页好的结果集 MLTS<pW/
ps.getIndexes()得到分页索引的数组 gS[B;+d
ps.getTotalCount()得到总结果数 ;g#nGs>
ps.getStartIndex()当前分页索引 7w9'xY
ps.getNextIndex()下一页索引 tx<^PV2
ps.getPreviousIndex()上一页索引 x5PM]~"p
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 [75?cQD
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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 dB#c$1
t`hes
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一下代码重构了。 cjGN=|`u
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我把原本我的做法也提供出来供大家讨论吧: PPG+~.7
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首先,为了实现分页查询,我封装了一个Page类: a;;
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java代码: 9\Ff z&
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/*Created on 2005-4-14*/ *mj=kJ7(
package org.flyware.util.page; 5-fASN.Lx
:!CnGKgt
/** PY '^:0
* @author Joa 8,h!&9
* 29G el
*/ +Z_VF30pa
publicclass Page { g&w~eWpk
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/** imply if the page has previous page */ 58HAl_8W
privateboolean hasPrePage; =IX-n$d`>
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/** imply if the page has next page */ Q{=r9&&
privateboolean hasNextPage; 38X{>*
=w!9:I&a0
/** the number of every page */ SnUR?k1
privateint everyPage; ,m0M:!hK
mc2uI-W
/** the total page number */ wS,fj gX
privateint totalPage; 7>r[.g
|"Zf0G
/** the number of current page */ c}S<<LR
privateint currentPage; +C7W2!I[G2
l+y;>21sTu
/** the begin index of the records by the current sb_/FE5e
cg]Gt1SU
query */ $E; Tj|W
privateint beginIndex; ydY(*]
rrgOp5aV"
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/** The default constructor */ ps` j>vX*
public Page(){ :,qvqh][
3jW&S
} 4|cRYZj5
g#6R(
/** construct the page by everyPage *6u2c%^
* @param everyPage znWB.H
* */ TT3GGHR
public Page(int everyPage){ \BfMCA/
this.everyPage = everyPage; +CSv@ />3
} )+,h}XqlX
B9
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/** The whole constructor */ O.y ?q
public Page(boolean hasPrePage, boolean hasNextPage, NB^Al/V@
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nW\W<[O9
int everyPage, int totalPage, "|&3z/AUh
int currentPage, int beginIndex){ oXk6,b"
this.hasPrePage = hasPrePage; jvR(e"
this.hasNextPage = hasNextPage; v/~&n
this.everyPage = everyPage; 8[AU`F8W
this.totalPage = totalPage; An?#B4:
this.currentPage = currentPage; 2Rwd\e.z
this.beginIndex = beginIndex; `) ],FE*:
} sieC7raO
E&t8nlTx
/** Fx1FxwIJ
* @return E^{!B]/oP
* Returns the beginIndex. *+6iXMwe
*/ (5:pHX`P
publicint getBeginIndex(){ >y#qn9rV1
return beginIndex; pih 0ME}z
} ~W4SFp
:?ZrD,D
/** I!kR:Z
* @param beginIndex RZnmia
* The beginIndex to set. Jwj=a1I 53
*/ 3gJZlH5IR
publicvoid setBeginIndex(int beginIndex){ bV'r9&[_6
this.beginIndex = beginIndex; tfm3IX
} y.8nzlkE{
y#`;[!
/** aEa+?6;D
* @return \=|=(kt)
* Returns the currentPage. a!u5}[{
*/ 8a8D0}'
publicint getCurrentPage(){ y|0/;SjV
return currentPage; ;;CNr_
} (OwGp3g
w<]-~`K
/** 1!U:M8T|
* @param currentPage wm?%&V/#
* The currentPage to set. Xj30bt
*/ Y+$]N:\F\
publicvoid setCurrentPage(int currentPage){ HSU?4=Q
this.currentPage = currentPage; BOA7@Zaa$p
} 7042?\\=
b *0u xvLu
/** #<
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* @return >X:!Y[N
* Returns the everyPage. K]yWpW
*/ ",Mrdxn7
publicint getEveryPage(){ 9FNsW$b?
return everyPage; /$\8?<Pc".
} z"7X.*]
&IRM<A!8
/** b&_Ifx_YF
* @param everyPage ~5Mj:{B
* The everyPage to set. R/E6n &R
*/ / <+`4n
publicvoid setEveryPage(int everyPage){ cAVdH{$"
this.everyPage = everyPage; z`Nss
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} $II~tO
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/** =^{MyR7
* @return l S
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* Returns the hasNextPage. Fe:
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*/ :1bDkoK
publicboolean getHasNextPage(){ (@^ySiU
return hasNextPage;
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} (w(k*b/
fsnZHL}=n
/** J
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* @param hasNextPage #D{Eq8dp
* The hasNextPage to set. 9Nv?j=*$
*/ '+g[n
publicvoid setHasNextPage(boolean hasNextPage){ jpW_q+^?
this.hasNextPage = hasNextPage; cuy9QBB
:
} bBo>Y7%
BOy&3.h5?
/** fWri7|"0h
* @return tgl 4pAc
* Returns the hasPrePage. k w
*/ OkT@ _U
publicboolean getHasPrePage(){ BE~-0g$W
return hasPrePage; _]D
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} !
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D8Mq '$-
/** 9pS:#hg
* @param hasPrePage N@!PhP
* The hasPrePage to set. Q^05n$ tI
*/ Vwjic2lGI
publicvoid setHasPrePage(boolean hasPrePage){ gnxD'1_
this.hasPrePage = hasPrePage; CM[83>
} ^si[L52BZ
)z4eRs F|
/** #&L7FBJ"*v
* @return Returns the totalPage. 9!Xp+<
* mU]^PC2[
*/ :!?Fq/!
publicint getTotalPage(){ yA_ly <
return totalPage; y;<}`
} !)W#|sys&
E:PPb9Kd
/** xpwy%uo
* @param totalPage ObS#aRq
* The totalPage to set. aX|(%1r
*/ "sY}@Q7
publicvoid setTotalPage(int totalPage){ }? c%L8\
this.totalPage = totalPage; nvNF~)mu
} &o1k_!25
d'3"A"9R7-
} Wyeb1
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hJir_=
I,)\506
MLmaA3
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 3=} P l,
hk
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个PageUtil,负责对Page对象进行构造: ~3f|-%Z
java代码: VhAJ1[k4!
e-\/1N84
3MKu!
/*Created on 2005-4-14*/ 7^LCP*
package org.flyware.util.page; :$PrlE
DxpJP,wY3
import org.apache.commons.logging.Log; Y3(I;~$!
import org.apache.commons.logging.LogFactory; yaWY>sB
+*Uv+oC|
/** Y"yrc0'&T
* @author Joa 0G33hIOS
* Cx.##n0
*/ G#6Z@|kVw
publicclass PageUtil { -!li,&,A1
>+Iph2]
privatestaticfinal Log logger = LogFactory.getLog nLv~)IQ}:
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(PageUtil.class); n4}e!
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/** p|dn&<kd
* Use the origin page to create a new page 7n+,!oJ
* @param page oayu*a.
* @param totalRecords ^&8hhxCPu|
* @return {~s\a2YH
*/ I;eoy,
publicstatic Page createPage(Page page, int eO*s,*
/{R.
totalRecords){ %.l={B,i
return createPage(page.getEveryPage(), dG]B-(WTC
?K:.Pa
page.getCurrentPage(), totalRecords); c=9A d
}
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M V!d*\
/** ;FF+uK
* the basic page utils not including exception y;<suGl
#<Xq\yC51
handler [m6+I9
* @param everyPage bqp^\yu-E
* @param currentPage $8AW
* @param totalRecords $|3zsi2
* @return page 84WcaH
*/ 6-)WXJ@V
publicstatic Page createPage(int everyPage, int H{S+^'5Y.
kS9;Tj cx
currentPage, int totalRecords){ Fu5Y<*x
everyPage = getEveryPage(everyPage); T]zD+/=
currentPage = getCurrentPage(currentPage); Y Q.Xl_
int beginIndex = getBeginIndex(everyPage, lz36;Fp
8~s0%%{,M
currentPage); ]FIIs58IM
int totalPage = getTotalPage(everyPage, X# ud5h
v>Kh5H5e~
totalRecords); g;6/P2w
boolean hasNextPage = hasNextPage(currentPage, Tcc83_Iq
P3Lsfi.
totalPage); CV\y60n
boolean hasPrePage = hasPrePage(currentPage); vTK8t:JQ~
\b8#xT}
returnnew Page(hasPrePage, hasNextPage, Ak kF6d+
everyPage, totalPage, ABkDOG2br
currentPage, x|dP-E41\
qBh@^GxY),
beginIndex); nLG)>L
} r Dlu&
UntFkoO
privatestaticint getEveryPage(int everyPage){ {Q_GJ
return everyPage == 0 ? 10 : everyPage; a7F_{Mm
} :9%e:-
eB1NM<V
privatestaticint getCurrentPage(int currentPage){ D M+MBK
return currentPage == 0 ? 1 : currentPage; I9>vm]
} 8AY;WL:;
Kl%[f jI)
privatestaticint getBeginIndex(int everyPage, int \/;c^!(<
J@E]Fl
currentPage){
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return(currentPage - 1) * everyPage; &ZkJ,-
} xRhGBb{@s
Ka-o$o[^u`
privatestaticint getTotalPage(int everyPage, int JehanF[
F~
\ONO5
totalRecords){ hif;atO
int totalPage = 0; YlGUd~$`"+
yUpN`;
if(totalRecords % everyPage == 0) CsycR @[
totalPage = totalRecords / everyPage; ?YZgH>7"
else #0uu19+}
totalPage = totalRecords / everyPage + 1 ; jQ%1lQ#R)
Mog [,{w
return totalPage; C,W_0=!e
} A:GqR;;"x>
HJ]e%og
privatestaticboolean hasPrePage(int currentPage){ Y9<[n)>+
return currentPage == 1 ? false : true; +ZW>JjP*
} iQ8{N:58DN
-Pt E+R[A
privatestaticboolean hasNextPage(int currentPage, RH _b
eF.nNu
int totalPage){ 9"+MZ$
return currentPage == totalPage || totalPage == :f39)g5>
6'/Zq
0 ? false : true; p}1gac_c
} ]?D$n
7qOkv1.}0
_BerHoQd
} V*Fy@
%%?}db1n
|UWIV
eZ]r"_?
/*Q3=Dse]
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 % R25, V
d$bO.t5CLh
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 r/a@ x9
gL&w:_
做法如下: Tc||96%2^
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 V61oK
H%U
的信息,和一个结果集List: ArAe=m!u
java代码: JvW7h(u7g
~(XaXu
\EoE/2"<
/*Created on 2005-6-13*/ BF gxa#De
package com.adt.bo; S}U_uZ$b
Y 'X!T8
import java.util.List; "i/GzD7 `n
hDW_a y4
import org.flyware.util.page.Page; $#s5y~z
sGtxqnX:J
/** ?;`GCE
* @author Joa JcmMbd&B
*/ 36+/MvIT
publicclass Result { R(^Sse
x/M$_E<G
private Page page; e4Y+u8gT
=UK:83R(
private List content; E2w-b^,5
'*rS,y
/** K g#Bg##
* The default constructor Aqf91
[c
*/ 8WP"~Js!
public Result(){ ^K1mh9O
super(); xPUukmG:B
} NJr)f
S>(x x"Ia
/** FO^6c
* The constructor using fields Oi: Hs
* 8Y RT0/V
* @param page WR#h~N
9c
* @param content dazML|1ow
*/ Qfy_@w]
public Result(Page page, List content){ z,m3U(
this.page = page; _oBx:G6E
this.content = content; ]] 0 M
} 86-Rm
?r&~(<^z
/** r5hkxk'
* @return Returns the content. DeF`#a0E
*/ Mpw]dYM
publicList getContent(){ z5iCQ4C<
return content; lN5PKsGl
} leNX5 sX
0Q7<;'m
/** }[PwA[k'
* @return Returns the page. [3-u7Fx!
*/ .Er+*j;&w
public Page getPage(){ 1/:vFX
return page; 6-"tQ,AZ
} diM*jN#
s-WZ3g
/** jJ<&!=
* @param content '\8YH+%It
* The content to set. [Ca''JqrA
*/ I$+=Fb'N0
public void setContent(List content){ O
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this.content = content; PV"\9OIKb.
} iN'T^+um=
NkBvN\CQ
/** iExKi1knx
* @param page dba_(I~y
* The page to set. MYara;k
*/ `{Oqb
publicvoid setPage(Page page){ Wq}6RdY$ZA
this.page = page; -wC}JVVcK
} w]T_%mdk
} |/l] ]+
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p.(+L^-=
(oy@j{G)c6
ojBdUG\
2. 编写业务逻辑接口,并实现它(UserManager, i.On{nB"k
2&:z[d}~H
UserManagerImpl) )3e_Hs+
java代码: oupWzjo
;rL1[qwk
ceks~[rP
/*Created on 2005-7-15*/ o!+'<IQ'
package com.adt.service; !fAvxR
+ XBF,<P
import net.sf.hibernate.HibernateException; A ?V-Sz#
v
))`U,Gm
import org.flyware.util.page.Page; {RI^zNgs[
-;"A\2_y
import com.adt.bo.Result; S#p_Y^A
z0ufLxq
/** Il@K8?H@
* @author Joa >ZPu$=[W
*/ [Nm?qY
publicinterface UserManager { 4x+[?fw
kkHK~(>G
public Result listUser(Page page)throws [vb#W!M&|
&${| o@
HibernateException; o?M ;f\Fy
TeZu*c
} h2mHbe43
4j'rbbs/
AdDR<IW
5 8;OTDR!
CfrO1i F
java代码: & }j;SK5
h0~<(3zC
5WfZd
/*Created on 2005-7-15*/ CL5^>.}
package com.adt.service.impl; "-Nyf
v4 rO 0y=C
import java.util.List; GGHeC/4
l>
H'PP~
import net.sf.hibernate.HibernateException; i}>EGmv m
NqKeQezX
import org.flyware.util.page.Page; 8|i<4>
import org.flyware.util.page.PageUtil; c%b|+4
}x
GcO:!b*YMp
import com.adt.bo.Result; :f7!?^;y>
import com.adt.dao.UserDAO; .7Qqs=Au
import com.adt.exception.ObjectNotFoundException; pQ7elv]
import com.adt.service.UserManager; _hJ+8B^`
OC,yL Q
/** 4n(w{W>
* @author Joa e"sv_$*
*/ #;8VBbc\^
publicclass UserManagerImpl implements UserManager { >HwVP.~HN
o%lxEd r
private UserDAO userDAO; h'G
wt@TR~a
/** IR2Qc6+{
* @param userDAO The userDAO to set. @0H0!9'
*/ @m`H~]AU
publicvoid setUserDAO(UserDAO userDAO){ V{>;Z vj1R
this.userDAO = userDAO; wS7Vo{#@\
} +Gy9K
FR'Nzi$
/* (non-Javadoc) L5d
YTLY
* @see com.adt.service.UserManager#listUser P$h) Y
DTi^* Wj
(org.flyware.util.page.Page) vYLspZ;S
*/ w0sy@OF
public Result listUser(Page page)throws C.uv0
_M;{}!Gc&A
HibernateException, ObjectNotFoundException { rB(Q)N
int totalRecords = userDAO.getUserCount(); A
-8]4p::
if(totalRecords == 0) r_bG+iw7p
throw new ObjectNotFoundException 7bGt'gvv
r0&LjH&R
("userNotExist"); (C`nBiL<
page = PageUtil.createPage(page, totalRecords); %t9Kc9u3p
List users = userDAO.getUserByPage(page); +",`Mb
returnnew Result(page, users); 16z
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} 9"B;o
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>
} lQ[JA[
I)*J,hs1
=:R${F
dYwEVu6q
9~K>c
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 U/v)6:j)4R
%M^Q{`
:5
询,接下来编写UserDAO的代码: Ym
-U{a
3. UserDAO 和 UserDAOImpl: =/ !A
java代码: 0@u{(m
~_ovQ4@
}p)a7xn}
/*Created on 2005-7-15*/ yVPFH~1@\
package com.adt.dao; Bv*VNfUm
%%wngiz\
import java.util.List; nddCp~NX
0T$ `;~
import org.flyware.util.page.Page; \b)P4aL
q9^.f9-
import net.sf.hibernate.HibernateException; <0l:B;3
8)`
/** '}>8+vU`
* @author Joa O7&OCo|b%>
*/ vj#m#1\f
publicinterface UserDAO extends BaseDAO { \
sz ](X
s1%2({wP
publicList getUserByName(String name)throws [P)](8nR[
5*B'e{C
HibernateException; mkBQTQGT
.rDao]K
publicint getUserCount()throws HibernateException; 8|hi2Qeu,c
"4*QA0As
publicList getUserByPage(Page page)throws cZWW[i
4l/~::y
HibernateException; <X97W\
+@@( C9
} 5':j=KQE_
h=NXU9n%'
4dSAGLpp
VF7H0XR/k5
wmP[\^c%$j
java代码: `"iPJw14
qX[C%
LzB*d
/*Created on 2005-7-15*/ jM'Fb.>~
package com.adt.dao.impl; D2:ShyYAS
k5)IBO
import java.util.List; 3VQmo\li
oye/tEMG
import org.flyware.util.page.Page; d;r,?/C
Jx4~ o{Z}c
import net.sf.hibernate.HibernateException; 7:.!R^5H
import net.sf.hibernate.Query; ;:)u
rI?
6H|T )
import com.adt.dao.UserDAO; \/y&l\ k)
%+
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/** |ew:}e: k<
* @author Joa % <%r
*/ ,fm{
krE
public class UserDAOImpl extends BaseDAOHibernateImpl TjctK [db@
R*vfp?x
implements UserDAO { >4T7DMy
MF::At[4
/* (non-Javadoc) I=K<%.
* @see com.adt.dao.UserDAO#getUserByName MY&?*pV)
V5I xZn%
(java.lang.String) iW?NxP
*/ JQ\o[t
publicList getUserByName(String name)throws 2
t]=-@
@c,=c+-
HibernateException { @oMl^UYM=
String querySentence = "FROM user in class 5pE@Ww
Nn5sD3z#
com.adt.po.User WHERE user.name=:name"; Oo%%f+
Query query = getSession().createQuery u,@x7a,z
X=JAyxY
(querySentence); KH[Oqd
query.setParameter("name", name); J8`vk#5
return query.list(); V}G;oz&>)
} .ityudT<
&gvX<X4e
/* (non-Javadoc) mgEZiAV ?
* @see com.adt.dao.UserDAO#getUserCount() =Ajw(I[56
*/ n]wZ7z
publicint getUserCount()throws HibernateException { .-p?skm=a
int count = 0; j 2Jew
String querySentence = "SELECT count(*) FROM ^F/H?V/PX
]G=^7O]`C!
user in class com.adt.po.User"; Fz_8m4
Query query = getSession().createQuery sJLJVSv8c
Qhn>aeW,
(querySentence); xx%*85 <
count = ((Integer)query.iterate().next gf|&u4D
3],[6%w
()).intValue(); 2FTJxSC
return count; $D#eD.
} )$FwB6^
gO!:WD
/* (non-Javadoc) *wz6 2p
* @see com.adt.dao.UserDAO#getUserByPage #!M;4~Sfx
HG})VPBa
(org.flyware.util.page.Page) 9'\*Ip^
*/ S L%lY
publicList getUserByPage(Page page)throws I [v~nY~l`
l8!n!sC[,
HibernateException { =ThacZHb8
String querySentence = "FROM user in class zeHs5P8}r
XE*#5u8t
com.adt.po.User"; mv9@Az9
Query query = getSession().createQuery ,W;2A0A?X
^G(+sb[t
(querySentence); #c2JWDH1F
query.setFirstResult(page.getBeginIndex()) uTUkRqtD!
.setMaxResults(page.getEveryPage()); N6S}u@{J~N
return query.list(); ;KW}F|
} fYZ)5xnj
km!jxs
} <UO'&?G
+Tp>3Jh2
EWoGdH|
KZTT2KsYl
SNf*2~uq)
至此,一个完整的分页程序完成。前台的只需要调用 lA7\c#
Y-:{a1/RKo
userManager.listUser(page)即可得到一个Page对象和结果集对象 ucC'SS
Ps7Bt(/
的综合体,而传入的参数page对象则可以由前台传入,如果用 t{ScK%S6
]1n
=O"vE
webwork,甚至可以直接在配置文件中指定。 mE_?E&T`|
rM(2RI4O`0
下面给出一个webwork调用示例: -*C+z!?BP
java代码: d+Jj4OnP
/=ro$@
`zOQ*Y&
/*Created on 2005-6-17*/ OX)[?1m8
package com.adt.action.user; @Vac!A??:
q%GlS=o"
import java.util.List; o%=OBTh_
TW?A/GoXI
import org.apache.commons.logging.Log; Ny)!uqul*
import org.apache.commons.logging.LogFactory; FQCz_z
import org.flyware.util.page.Page; '0>w_ge4
2AI~Jm#
import com.adt.bo.Result; M2e_)f:
import com.adt.service.UserService; ;?0k>
import com.opensymphony.xwork.Action; %,G0)t
}zu?SZH
/** 72 >/@
* @author Joa
^iaG>rvA
*/ 3 ]}wZY0
publicclass ListUser implementsAction{ }
^67HtNQ
b7h0V4w
privatestaticfinal Log logger = LogFactory.getLog $@cg+Xrg1
.#y.:Pb|e
(ListUser.class); W-+~r
\>*B
private UserService userService; ril4*$e7^\
zDO`w0N
private Page page; Wr Nm:N
+\n8##oAI
privateList users; d' Z
8(c,b
/* Mm+kG'Z!S
* (non-Javadoc) 8 P=z"y
* N
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* @see com.opensymphony.xwork.Action#execute() qkN{l88
*/ t1)Qa(#]
publicString execute()throwsException{ D|p`~(
Result result = userService.listUser(page); 2-*zevPiG=
page = result.getPage(); Jx8?x#}
users = result.getContent(); ~4fjFo&