Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 rVoV@,P
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 PDuBf&/e
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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 ~o"=4q`>
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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 ~h;
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分页支持类: oYZ
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java代码: ; /K6U
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package com.javaeye.common.util; f?)7MR=
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import java.util.List; J*$%d1
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publicclass PaginationSupport { }" vxYB!h3
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publicfinalstaticint PAGESIZE = 30; 2WFZ6
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privateint pageSize = PAGESIZE; 7N[".V]c
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privateList items; lsOv#X-bE
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privateint totalCount; bN zb#P#hP
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privateint[] indexes = newint[0]; n*wQgC'vw
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privateint startIndex = 0; kP&I}RY
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public PaginationSupport(List items, int rBTg"^jsw
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totalCount){ nWIZ0Nde'
setPageSize(PAGESIZE); rtJER?A
setTotalCount(totalCount); Y|fD)zG_
setItems(items);
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setStartIndex(0); )0exGx+:
} -|#{V.G3'
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public PaginationSupport(List items, int K_)~&Cu*'
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totalCount, int startIndex){ VRQ`-#
setPageSize(PAGESIZE); WK`o3ayH-
setTotalCount(totalCount); M8X6!"B$Y
setItems(items); {f#QZS!E
setStartIndex(startIndex); I$t8Ko._"
} AF{uFna
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public PaginationSupport(List items, int D :U6r^c
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totalCount, int pageSize, int startIndex){ <}{<FXk[
setPageSize(pageSize); c#{lXS^
setTotalCount(totalCount); MOaI~xZ
setItems(items); iF^qbh%%E
setStartIndex(startIndex); ^:{8z;w!(
} xX%ppD7
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publicList getItems(){ N<:c*X
return items; ]|CcQ1#|H
} Yvo*^jv
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publicvoid setItems(List items){ v}j5G,
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this.items = items; mufGv%U2
} o{,IO!q
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publicint getPageSize(){ FprdP*/
return pageSize; ]{6/6jl
} u>fMO9X}2
wkx9@?2*
publicvoid setPageSize(int pageSize){ R QQ'Wg
this.pageSize = pageSize; D#&9zR86F
} LVB wWlJ
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publicint getTotalCount(){ D wJ^ W&*
return totalCount; mBErU6?X,A
} (`dz37@*
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publicvoid setTotalCount(int totalCount){ Ux=~-}<-w
if(totalCount > 0){ #("M4}~
this.totalCount = totalCount; ,yGbMOV
int count = totalCount / YQN:&Cls
E,6|-V;?
pageSize; c36p+6rJk=
if(totalCount % pageSize > 0) @FN|=?8%
count++; nKm#
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indexes = newint[count]; 5,gT|4|B\g
for(int i = 0; i < count; i++){ 5VTVx1P[8
indexes = pageSize * aG
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i; -n 9&W
} ^\ x'4!W
}else{ fY&TI}Y
this.totalCount = 0; #!F>cez
} xA
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} S<i1t[E@W
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publicint[] getIndexes(){ O.B9w+G=
return indexes; 2/4zg
} t<` As6}
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publicvoid setIndexes(int[] indexes){ ]oV{JR]
this.indexes = indexes;
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} RdPk1?}K
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publicint getStartIndex(){ \lQ3j8U
return startIndex; bIiuna\
} y{@\8B]
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publicvoid setStartIndex(int startIndex){ e|{R2z"^
if(totalCount <= 0) X+]>pA
this.startIndex = 0; lZ-U/$od
elseif(startIndex >= totalCount) ~-zIB=TyK
this.startIndex = indexes ,N(Yjq"R
nnj<k5
[indexes.length - 1]; H7tviSTd
elseif(startIndex < 0) jvB[bS`<H
this.startIndex = 0; t\ oud{Cv
else{ N 5*Qnb8
this.startIndex = indexes 4tCM2it%
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[startIndex / pageSize]; I*N"_uKU
} -NJpql{Cb
} t/;0/ql\
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publicint getNextIndex(){ N~=I))i
int nextIndex = getStartIndex() + y-3'qq'E
*Mhirz%iD
pageSize; \~*<[.8~
if(nextIndex >= totalCount) 4 -tC=>>wc
return getStartIndex(); S&}7XjY
else {d[Nc,AMb
return nextIndex; g}0K@z3
} U&#`
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VP
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publicint getPreviousIndex(){ 9\.0v{&v
int previousIndex = getStartIndex() - G~5pMyOR
/7D5I\
pageSize; .JLJ(WM
if(previousIndex < 0) 'UsR/h5T
return0; `TJhH<z"%
else ^nPy(Q0
return previousIndex; O(W"QY
} nz?[
xJ$uoy3+
} zTcz+3x
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抽象业务类 k";dK*hD,
java代码: C!^A\T7p
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/** {*O%A
* Created on 2005-7-12 0FcDO5ia
*/ vSnVq>-q&
package com.javaeye.common.business; 3`reXms*{
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import java.io.Serializable; 16/ V5
import java.util.List; yb',nGl~
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import org.hibernate.Criteria; Vx<{cHQQ
import org.hibernate.HibernateException; ;9j ]P56
import org.hibernate.Session; +=J$:/&U
import org.hibernate.criterion.DetachedCriteria; r[V%DU$dj
import org.hibernate.criterion.Projections; &5-1Cd E
import VkJ">0k
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org.springframework.orm.hibernate3.HibernateCallback; i$] :Y`3h
import @HbRfD/!
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org.springframework.orm.hibernate3.support.HibernateDaoS clU ?bF~e1
hhPQ.{]>
upport; e^eJ!~0
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import com.javaeye.common.util.PaginationSupport; 8j>V?'Szk
S} UYkns*
public abstract class AbstractManager extends H7+z"^s*
"~ID.G|<
HibernateDaoSupport { SOR\oZ7
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privateboolean cacheQueries = false; [UXVL}tk
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privateString queryCacheRegion; }SWfP5D@
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publicvoid setCacheQueries(boolean k4$zM/ob
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cacheQueries){ x,^-a
this.cacheQueries = cacheQueries; ZOfv\(iJ;
} fC'u-m?!Q'
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publicvoid setQueryCacheRegion(String y<6Sl6l*
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queryCacheRegion){ p'LLzc##
this.queryCacheRegion = g
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queryCacheRegion; 0 8L;u7u
} tkV[^OeU>
#D_Ti%.^}
publicvoid save(finalObject entity){ T2rwK2
getHibernateTemplate().save(entity); R7rM$|n=o
} z+.G>0M
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publicvoid persist(finalObject entity){ \9,lMK[b
getHibernateTemplate().save(entity); %6(\Ki6I
} =k<b* 8
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publicvoid update(finalObject entity){ R^`}DlHX
getHibernateTemplate().update(entity); #"6l+}
} JYNnzgd
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publicvoid delete(finalObject entity){ 9QP=
getHibernateTemplate().delete(entity); 8WDL.IO
} e*'bY;8lo
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publicObject load(finalClass entity, (+v':KH3_
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finalSerializable id){ D>jtz2y=D
return getHibernateTemplate().load @XG1d)sE
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(entity, id); {s@!N
} Ydsnu
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publicObject get(finalClass entity, mH;t)dT
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finalSerializable id){ @{qcu\sZ
return getHibernateTemplate().get H%n/;DW
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(entity, id); ^kK")+K
} pWzYC@_W
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publicList findAll(finalClass entity){ 4;~xRg;u&*
return getHibernateTemplate().find("from ww
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" + entity.getName()); H$?MPA-c
} W:<2" &7
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publicList findByNamedQuery(finalString "n3n-Y#'
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namedQuery){ EIzTbW{p
return getHibernateTemplate e?(4lD)d
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().findByNamedQuery(namedQuery); Wp
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} Z5rL.a&
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publicList findByNamedQuery(finalString query, =^M Q 4
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finalObject parameter){ =Cf@!wZ^
return getHibernateTemplate
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().findByNamedQuery(query, parameter); w@P86'< v
} -GL.8"c[
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publicList findByNamedQuery(finalString query, HHyN\
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finalObject[] parameters){ }6u}?>S
return getHibernateTemplate [EPRBK`=
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().findByNamedQuery(query, parameters); uAYDX<Ja9
} 0Q>
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publicList find(finalString query){ :p<:0W2!
return getHibernateTemplate().find -{L 7%j|R
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(query); 'h&>K,U?5
} f
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publicList find(finalString query, finalObject #?M[Q:
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parameter){ sn[<Lq
return getHibernateTemplate().find \o,et9zDJ3
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(query, parameter);
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} !x-9A
@(/$;I,
public PaginationSupport findPageByCriteria Ei,dO;&
=*(_sW6;
(final DetachedCriteria detachedCriteria){ Xhyc2DKa_
return findPageByCriteria 6a]Qg99\
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); ,uO?f1
} |.~2C14[
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public PaginationSupport findPageByCriteria =v !8i
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(final DetachedCriteria detachedCriteria, finalint 4tiCxf)
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startIndex){ :d<F7`k
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return findPageByCriteria yF
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(detachedCriteria, PaginationSupport.PAGESIZE, ]R"n+LnI:=
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startIndex); BW`Tw^j
} p)7U%NMc(*
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public PaginationSupport findPageByCriteria I*+*Wf
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(final DetachedCriteria detachedCriteria, finalint 0ZAtBq.s
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pageSize, dm83YCdL
finalint startIndex){ @`sZV8
return(PaginationSupport) z[+pN:47
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getHibernateTemplate().execute(new HibernateCallback(){ KH$o X\v
publicObject doInHibernate d$D3iv^hyx
yrMakT =
(Session session)throws HibernateException { nzi)4"3O
Criteria criteria = :=`N2D
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detachedCriteria.getExecutableCriteria(session); hG/Z65`&
int totalCount = |msQ
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((Integer) criteria.setProjection(Projections.rowCount `Z#]lS?
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()).uniqueResult()).intValue(); U,2\ TBz
criteria.setProjection b\"2O4K,)
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(null); rYA4(rYq
List items = xe1xP@e?
m,]h7 xx
criteria.setFirstResult(startIndex).setMaxResults ^@q$c
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(pageSize).list(); `ucr;P
PaginationSupport ps = `{@?O%UB
>\ ym{@+*
new PaginationSupport(items, totalCount, pageSize, pc_$,RkN
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startIndex); !8%{(;(
return ps; IPh_QE2g
} (XA]k%45
}, true); h,Tsb:Q"M
} 1QDAfRx
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public List findAllByCriteria(final X?] 1/6rV
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DetachedCriteria detachedCriteria){ T CO^9RP<
return(List) getHibernateTemplate "IsDL^)A9
NB/ wJ3 F
().execute(new HibernateCallback(){ T$xY]hqr
publicObject doInHibernate Z}6H529[
}"9jCxXL
(Session session)throws HibernateException { [hXU$Y>"0
Criteria criteria = W-U[7n
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detachedCriteria.getExecutableCriteria(session); L
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return criteria.list(); \5^GUT
} iu.+bX|b
}, true); bX]$S 5c_u
} k*xgF[T
8
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public int getCountByCriteria(final bQ2 '*T
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DetachedCriteria detachedCriteria){ A&QO]8
Integer count = (Integer) (}n,Ou[
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getHibernateTemplate().execute(new HibernateCallback(){ A
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publicObject doInHibernate e?~6HP^%.
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(Session session)throws HibernateException { I_@XHhyVZ
Criteria criteria = iY1JU-S
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detachedCriteria.getExecutableCriteria(session); Cy##+u,C
return $nbZ+~49
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criteria.setProjection(Projections.rowCount w873: =
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()).uniqueResult(); +3n07d
} "8Y4;lbN.q
}, true); lGZ^ 8
return count.intValue(); kC)ye"r
} $n?@zd@53
} OL|UOG
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cvvba 60
lf\]^yM #
用户在web层构造查询条件detachedCriteria,和可选的 n-n{+Dl!
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 p M:lg
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PaginationSupport的实例ps。 >;.'$-
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ps.getItems()得到已分页好的结果集 2!b+}+:
ps.getIndexes()得到分页索引的数组 -HU5E>xG
ps.getTotalCount()得到总结果数 P p[?E.]P
ps.getStartIndex()当前分页索引 fWywegh
ps.getNextIndex()下一页索引 0x\bDWZ_
ps.getPreviousIndex()上一页索引 gUB%6v G\I
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 r-s.i+\
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,尤其是上面的示例代码,让我着实觉得该对我原来的分页查询做 gZe(aGh
9a5x~Z:'
一下代码重构了。 tTB,eR$
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我把原本我的做法也提供出来供大家讨论吧: c3&;Y0SD
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首先,为了实现分页查询,我封装了一个Page类: {re<S<j&
java代码: r_f?H@ v
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/*Created on 2005-4-14*/ 0m^(|=N-
package org.flyware.util.page; #%xzy@`
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/** 6.| {l8%r
* @author Joa 90oG+T4
* tk@
T-;
*/ xG JX~)
publicclass Page { p^~AbU'6~
RG9YA&1ce
/** imply if the page has previous page */ ykv,>nSXLL
privateboolean hasPrePage; k[0Gz
|^^'GZ%a
/** imply if the page has next page */ G'oMZb ({=
privateboolean hasNextPage; x roo_
5J^S-K^r
/** the number of every page */ 82.::J'e
privateint everyPage; J|-X?V;ZW
x78`dX
/** the total page number */ l&@]
privateint totalPage; B zmmE2~*
A{Jp>15AVg
/** the number of current page */ $^F
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privateint currentPage; qU(,q/l
3 xSt -MA
/** the begin index of the records by the current ALVHKL2
b!C\J
query */ K!c "g,S
privateint beginIndex; rz%8Vigb
hSQuML
#)&kF+
/** The default constructor */ x{_:B
DY
public Page(){ Ib(q9!L
+>b~nK>M
} &DQyJJ`k
.v?x>iV
/** construct the page by everyPage \wR $_X&
* @param everyPage !2-f%x]tO
* */ _?"P<3/iF
public Page(int everyPage){ uURm6mVt9:
this.everyPage = everyPage; c]SXcA;Pmv
} z>rl7&[@
=P}ob eY
/** The whole constructor */ $l05VZ
public Page(boolean hasPrePage, boolean hasNextPage, CatbEXO
=hZ#Z]f
TI^W=5W@@
int everyPage, int totalPage, }^!8I7J.
int currentPage, int beginIndex){ $T.u Iq
this.hasPrePage = hasPrePage; N8hiv'3
this.hasNextPage = hasNextPage; I$.HG]
this.everyPage = everyPage; w$Zi'+&*
this.totalPage = totalPage; vGe];
this.currentPage = currentPage; *$K_Tii
this.beginIndex = beginIndex; h$p]M^Z7
} ,E8:!r)6
T?vM\o%i3
/** UoAHy%Y<%
* @return ZqtL4M~9
* Returns the beginIndex. GRM:o)4;#
*/ e"7<&%
Oq
publicint getBeginIndex(){ T_\Nvzb}
return beginIndex; ;gS)o#v0
} Y fRjr
t1Ty.F)r
/** nHAET
* @param beginIndex eh\_;2P
* The beginIndex to set. S#h-X(4
*/ ~
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publicvoid setBeginIndex(int beginIndex){ 2/Xro rV
this.beginIndex = beginIndex; b 6kDkE
} s7(NFX5
\wMqVRPoQ
/** 6T"4<w[
* @return ``X1xiB
* Returns the currentPage. RT+pB{Y
*/ WP5cC@x
publicint getCurrentPage(){ JVfSmxy.
return currentPage; ( *~ '#k
} 6,wi81F,}
2IfcdYG
/** 0d>|2QV
* @param currentPage F9ytU> zh
* The currentPage to set. %y96]e1
*/ e}f#dR+(
publicvoid setCurrentPage(int currentPage){ voX4A
pl
this.currentPage = currentPage; O0Z!*Hy
} ^/6LVB *
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"
/** vIq>QXb;d
* @return '80mhrEutG
* Returns the everyPage. wh Hp}r
*/ %#go9H(K
publicint getEveryPage(){ _HMQx_e0YM
return everyPage; k)j6rU
} ={'3j
;$nCQ/ /
/** 0P_=Oy"l-
* @param everyPage /penB[1i
* The everyPage to set. Dj9v9
*/ ~,^pya
publicvoid setEveryPage(int everyPage){ #%9t-
this.everyPage = everyPage; 9%#u,I
} Rb/|ae
^X]rFY1
/** u0Q6+U
* @return _xWX/1DY
* Returns the hasNextPage. %I^schE*
*/ ;*c8,I;
publicboolean getHasNextPage(){ "?*B2*|}`
return hasNextPage; ,=a+;D]'
} ]F{F+r
#]rfKHW9
/** G;ihm$Cad
* @param hasNextPage $~3?nib"j
* The hasNextPage to set.
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*/ FOyANN'
publicvoid setHasNextPage(boolean hasNextPage){ wC>}9OM
this.hasNextPage = hasNextPage; 7v']wA r]
} Wq2Bo*[*
~|Nj+A
/** 2%?Kc]JY9
* @return $x~U&a
* Returns the hasPrePage. gB_gjn\
*/ w,T-vf
publicboolean getHasPrePage(){ g+j\wvx0
return hasPrePage;
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} 8l>7=~Egp
q _INGCJ
/** o[aP+O Md
* @param hasPrePage mI,a2wqi
* The hasPrePage to set. >6KwZr BB
*/ aCRiW;+'
publicvoid setHasPrePage(boolean hasPrePage){ #Zg pm"MW
this.hasPrePage = hasPrePage; ]."t
} x' v-]C(@
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/** `t7z
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* @return Returns the totalPage. fKbg ?
* 1f+z[ad&^
*/ no$X0ia
publicint getTotalPage(){ {zI>"%$u
return totalPage;
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} kp-`_sDg
P6 7*-Ki
/** 2Rqpok4
* @param totalPage Ofc
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* The totalPage to set. /pC60y}O0
*/ :-Wh'H(
publicvoid setTotalPage(int totalPage){ HPY;UN
this.totalPage = totalPage; [Mk:Zz%
} j.yh>"de
/s~BE ,su
} 6/.kL;AI
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N^{}Qvrr
_oHxpeM
P\y ZcL
上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 0Of6$`
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个PageUtil,负责对Page对象进行构造: 2c'<rkA
java代码: *&z!y/
RGLJaEl !
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/*Created on 2005-4-14*/ qL?$u07<9'
package org.flyware.util.page; FMtg7+Q|>
sk5B} -
import org.apache.commons.logging.Log; zWrynJ}s
import org.apache.commons.logging.LogFactory; L0R$T=~%)
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/** F@KtRUxE
* @author Joa Gs>4/
* !<<wI'8
*/ Jsa;pG=3&
publicclass PageUtil { :(K JLa]
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privatestaticfinal Log logger = LogFactory.getLog gL&)l!2Y
e**5_L
(PageUtil.class); _Qq lOc9
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/** EeQ2\'t
* Use the origin page to create a new page CHVAs9mrNB
* @param page [4Q;5 'Dj
* @param totalRecords OGcW]i
* @return BQ=JZ4&
*/ t:P]G>)x|
publicstatic Page createPage(Page page, int f.c2AY~5[
B@ >t$jK
totalRecords){ On(.(7sNc
return createPage(page.getEveryPage(), yb-4[C:i
@zJiR{Je-U
page.getCurrentPage(), totalRecords); `Bb32L
} xS; tmc
#"-DE-I[
/** wkY$J\J
* the basic page utils not including exception `NyO|9/4
HOr Xxxp1^
handler n0)y|B#
* @param everyPage y,6KU$G
* @param currentPage >x]ir
* @param totalRecords 8yybZ@
* @return page \' &,9lP
*/ R*H-QH/H1
publicstatic Page createPage(int everyPage, int &srD7v9M8
psuK\s
currentPage, int totalRecords){ ky'G/z
everyPage = getEveryPage(everyPage); BO+to.
currentPage = getCurrentPage(currentPage); S
rhBU6K
int beginIndex = getBeginIndex(everyPage, TCK#bJ
{]iM5?
currentPage); T[-Tqi NT
int totalPage = getTotalPage(everyPage, ~lbm^S}-
@o&UF-=MW(
totalRecords); BnG{)\s
boolean hasNextPage = hasNextPage(currentPage, d>0 j!+s
HP=5a.
totalPage); YXg^t$
boolean hasPrePage = hasPrePage(currentPage); _y:aPn
\okvL2:!
returnnew Page(hasPrePage, hasNextPage, Z ?ATWCa
everyPage, totalPage, aqgm
currentPage, u~!Pzz3"
\Hu?K\SWs
beginIndex); bV:MOj^
} ,nWZJ&B
of'H]IZ
privatestaticint getEveryPage(int everyPage){ U%K gLg#
return everyPage == 0 ? 10 : everyPage; [4-u{Tu
} ;+n25_9
S-79uo
privatestaticint getCurrentPage(int currentPage){ +D?Re%HI
return currentPage == 0 ? 1 : currentPage; &-KQ
m20n
} {~V_6wY g
X=VaBy4#
privatestaticint getBeginIndex(int everyPage, int 4rypT-%^ ;
GXR7Ug}k
currentPage){ jF{)2|5
return(currentPage - 1) * everyPage; U8eU[|-8O/
} &D` $YUl@
]_hXg*?
privatestaticint getTotalPage(int everyPage, int s5ILl wr
F~3 &@TWi
totalRecords){ 5IP@_GV|
int totalPage = 0; R+Rb[,m
f|,2u5
;z
if(totalRecords % everyPage == 0) &>Z p}.V
totalPage = totalRecords / everyPage; mFyYn,Mu|
else N8Un42
totalPage = totalRecords / everyPage + 1 ; `nL^]i
}b>e
lz
return totalPage; V_9>Z?
} RohD.`D
wEEFpn_
privatestaticboolean hasPrePage(int currentPage){ >+S* Wtm5
return currentPage == 1 ? false : true; % %QAC4
} u]<`y6=&C
Jh%k:TrBm
privatestaticboolean hasNextPage(int currentPage, nVk]Qe
PU%WpI.w
int totalPage){ {'Gu@l
return currentPage == totalPage || totalPage == J|b:Zo9<f"
>H?~2O
0 ? false : true; tmC9p6%
} &uJ7[m19z
S4%MnT6Uy
)Ju$PrO
} e0<L^|S
u_S>`I
"HbrYYRb'
s`,. &
fQ,(,^!;
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。 9'!I6;M
4\Cb4jq%/
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 [mQ*];GA
^Cn_
ODjo
做法如下: [oS.B\Vc
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 }u~r.=
y{\(|j
的信息,和一个结果集List: }{e7wqS$&,
java代码: G$
Ii
\4&FW|mx
Gp))1b';
/*Created on 2005-6-13*/ ?[q.1O
package com.adt.bo; &?7+8n&+
:=%`\\
import java.util.List; XcQ'(
!O#NP!
import org.flyware.util.page.Page; 9rQpKq:#
E
Q"H1(kG|
/** |p+ xM
* @author Joa W$Zc;KRz$0
*/ LL=nMoS
publicclass Result { Jx= v6==7
"a>a
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private Page page; 6b#J!:?
610hw376B
private List content; wz]OM
atWAhN
/** eVy\)dCsU
* The default constructor t2vo;,^euL
*/ Ic&Jhw;]z
public Result(){ #-u?+Nk/
super(); S#,
E)h/
} f<G:}I
)haHI)xR
/** *G0r4Ui$
* The constructor using fields -* ;`~5
* Fh$Xcz~i
* @param page ^!>o5Y)
* @param content @uI_4 a
*/ v:$Y
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public Result(Page page, List content){ jP|(y]!
this.page = page; \muC_9ke
this.content = content; )|@UY(VZ^
} nxh9'"th
~WG#Zci-
/** p![CH
* @return Returns the content. Y+I`XeY
*/ e#$ZOK)`
publicList getContent(){ L1E\^)
return content; s"\o6r
,
} S}cm.,/w
o\YF_235
/** 6?c(ue iL[
* @return Returns the page. I~>L4~g)
*/ h47l;`kD-#
public Page getPage(){ #0j,1NpL
return page; xN#. Pm~
} B]YY[i
$?u ^hMU=
/** i
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* @param content Ka\%kB>*`
* The content to set. SggS8$a`
*/ fX2PteA0qX
public void setContent(List content){ S?_ ;$Cn
this.content = content; 3QrYH
@7zx
} pJE317 p'
U ]6Hml;l
/** yegTKoY
* @param page B[0XzV]Z
* The page to set. %%w]-`^h,
*/ 3q.O^`y FU
publicvoid setPage(Page page){ L_YVe(dT
this.page = page; >2l;KVm%
} T+[N-"N
} j@b4)t
{<- BU[H
ZrFC#wJb
8?r
,ylUj
}$ Am;%?p
2. 编写业务逻辑接口,并实现它(UserManager, ]S~Z8T-[
Dyj5a($9"{
UserManagerImpl) $h-5PwHp
java代码: bG0t7~!{E
#`mo5
pcw^W
/*Created on 2005-7-15*/ |mfQmFF
package com.adt.service; "3v[\M3
98os4}r
import net.sf.hibernate.HibernateException; D`lTP(] y
/)PD+18
import org.flyware.util.page.Page; )vK
%LmP
B&`hvR
import com.adt.bo.Result; PQRh5km
YGObTIGJvf
/** ~Cj55S+
* @author Joa ?*z#G'3z1
*/ :sBg+MS
publicinterface UserManager { g(Jzu'
v 6?{g
public Result listUser(Page page)throws !z;a>[T'
sgo({zA`i
HibernateException; 'Z+~G
z2&SZ.mk
} +?~'K&@
u4=j!Zb8}
e1X*}OI
z1ltc{~Z
}06
java代码: PQsqi;=)
J8$G-~MeJ
DLkNL?a
/*Created on 2005-7-15*/ $@t-Oor;
package com.adt.service.impl;
M? oK@i
V,($I'&/
import java.util.List; b$nXljV4?
4XDR?KUM
import net.sf.hibernate.HibernateException; 9
I> 3p4]
2@o_7w98
import org.flyware.util.page.Page; FG-w7a2mn
import org.flyware.util.page.PageUtil; Nf>1`eP
02} &h
import com.adt.bo.Result; A}sb2P
import com.adt.dao.UserDAO; $L.0$-je4
import com.adt.exception.ObjectNotFoundException; ZN|DR|cUY
import com.adt.service.UserManager; qbkvwL9
@M?N[LG
/** A:1O:LB=!
* @author Joa t#~r'5va
*/ nv(Pwb3B
publicclass UserManagerImpl implements UserManager { N
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dfe 9)m>
private UserDAO userDAO; hq/\'Z&!+P
pK#Ze/!
/** SG8H~]CO)
* @param userDAO The userDAO to set. z_eP
*/ 5,'?NEyw
publicvoid setUserDAO(UserDAO userDAO){ [SgP1>M
this.userDAO = userDAO; r:y*l4
} h%(dT/jPL)
{>G\3|^D
/* (non-Javadoc) s@f4f__(]
* @see com.adt.service.UserManager#listUser l0g#&V--
rB|D^@mG
(org.flyware.util.page.Page) -Xkdu?6Eh
*/ 28-6(oG
public Result listUser(Page page)throws *~fZ9EkD
|^Z1 D TAw
HibernateException, ObjectNotFoundException { L*9^-,
int totalRecords = userDAO.getUserCount(); n6[bF"v
if(totalRecords == 0) r^&{0c&o
throw new ObjectNotFoundException 46*o_A,"
tn;e
PcU
("userNotExist"); 6z"fBF
page = PageUtil.createPage(page, totalRecords); $GUSTV
List users = userDAO.getUserByPage(page); XZA3TZ
returnnew Result(page, users); 3~BL!e,
} }#q9>gx
*8U+2zgfC
} b/ 'fC%o,
t/_w}
-c%GlpZw
52tIe|KwL
f!*b8ND^R
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 5SK{^hw
?};}#%971
询,接下来编写UserDAO的代码: }+QgRGQ
3. UserDAO 和 UserDAOImpl: ,>2ijk#
java代码: EKk~~PhW 8
{.z2n>1J{T
AShJtxxa
/*Created on 2005-7-15*/ |t|+pBB
package com.adt.dao; z['>`Kt
*4r
1g+0
import java.util.List; 9">}@1k
WYwsTsG{_
import org.flyware.util.page.Page; 1fQvh/2
>ALU}o/
import net.sf.hibernate.HibernateException; zrE
~%YR
on(F8%]zE
/** z}s0D]$+x
* @author Joa 95aa
*/ 2;5EH0
publicinterface UserDAO extends BaseDAO { ! k||-Q&
V{$(#r
publicList getUserByName(String name)throws -Duy:C6W
+%6{>C+bZo
HibernateException; S3:Pjz}t
0(ZER sP
publicint getUserCount()throws HibernateException; <m`HK.|~
.jZmQtc
publicList getUserByPage(Page page)throws >;nE.]
De4UGX
HibernateException; IQoz8!guh:
85m[^WGyh
} v@LK3S/!3
>yg mE`g
R"Hhc(H
:+/V
cG,B;kMjo
java代码: 1s=M3m&H
K/+5$SjF
K&9|0xt
/*Created on 2005-7-15*/ y;yXOE_
package com.adt.dao.impl; 0lF[N.!\9
5 r"`c
import java.util.List; 0MF[e3)a
.Hl]xI$;+
import org.flyware.util.page.Page; -B9C2
mgL~ $
import net.sf.hibernate.HibernateException; R?(0:f
import net.sf.hibernate.Query; F5gL-\6
?7@B$OlU
import com.adt.dao.UserDAO; j =r`[Bm
o
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/** 8V;@yzIha
* @author Joa {tV)+T
*/ %8>s :YG
public class UserDAOImpl extends BaseDAOHibernateImpl 4g b2$" !
&kHp}\
implements UserDAO { J i :2P*
VD;Ot<%
/* (non-Javadoc) V2,54YE
* @see com.adt.dao.UserDAO#getUserByName U voX\
GX&BUP\
(java.lang.String) =_\5h=`Yx
*/ n%"q>
publicList getUserByName(String name)throws >:Na^ +c
Y]P';C_eP
HibernateException { wP/&k`HQ#i
String querySentence = "FROM user in class 'LpJ:Th
tlV>
com.adt.po.User WHERE user.name=:name"; Q'~kWmLf
Query query = getSession().createQuery >t)vQ&:;u
U>IllNd
(querySentence); !Sy._NE`z
query.setParameter("name", name); _Buwz_[&
return query.list(); P\tP0+at
} U,LW(wueT
';hU&D;s
/* (non-Javadoc) lt|\$Iy(
* @see com.adt.dao.UserDAO#getUserCount() |o6
h:g
*/ XpdDIKMmE
publicint getUserCount()throws HibernateException { #25Z,UU
int count = 0; 6B)(kPW
String querySentence = "SELECT count(*) FROM ~.u}v~
F
T(MS,AyD]
user in class com.adt.po.User"; Sav]Kxq{
Query query = getSession().createQuery M")J buI
@ H=
d8$
(querySentence); AMG}'P:
count = ((Integer)query.iterate().next ^I~2t|}
|Up+Kc:z/n
()).intValue();
7"2L|fG
return count; S 3Tp__
} 9 JBPE
.9
mwRYgD
/* (non-Javadoc) C<?}?hhb
* @see com.adt.dao.UserDAO#getUserByPage KoRJ'WW^
o%i^t4J$e
(org.flyware.util.page.Page) PBbJfm
*/ yQ}$G
,x
publicList getUserByPage(Page page)throws l)[\TD
Bq.@CxK
HibernateException { T1m"1Q
String querySentence = "FROM user in class QM2Y?."#
;n%SjQ'%
com.adt.po.User"; 8>x!n/z)
Query query = getSession().createQuery '3 w=D
)
"^F#oo%L
(querySentence); :6S!1roi
query.setFirstResult(page.getBeginIndex()) 1 !bODd
.setMaxResults(page.getEveryPage()); Y ( x_bJ
return query.list(); XAW$"^p
} >G$8\&]j
1uZ[Ewl]
} (MY#;v\AYE
n1m[7s.[&
F B9PIsFS
;,[6 n|M
z6ISJb
至此,一个完整的分页程序完成。前台的只需要调用 DZ92;m
&)JQ6J_|\
userManager.listUser(page)即可得到一个Page对象和结果集对象 'DO^ ($N
_ui03veA1
的综合体,而传入的参数page对象则可以由前台传入,如果用 5XySF #
`E+)e?z
webwork,甚至可以直接在配置文件中指定。 f uQbDb&
$h`(toTyF
下面给出一个webwork调用示例: !O6e,l
java代码: k!3X4;F!_
gKeqf-UWKJ
?YWfoH4mS
/*Created on 2005-6-17*/ +%Q:
package com.adt.action.user; ,A`d!{]5
0{^vqh.La
import java.util.List; 1rKKp h
u\wdb^8ds
import org.apache.commons.logging.Log; T]Z|Wq`bot
import org.apache.commons.logging.LogFactory; wwrP7T+d
import org.flyware.util.page.Page; dE19_KPm[j
"[2CV!_
import com.adt.bo.Result; l*>t@:2J
import com.adt.service.UserService; 'KB\K)cD=3
import com.opensymphony.xwork.Action; 6zh<PETa03
lffp\v{w
/** Hy^Em
* @author Joa ;*1bTdB5a
*/ uPKq<hBI
publicclass ListUser implementsAction{ ?j;e/r.
i!+D
,O
privatestaticfinal Log logger = LogFactory.getLog BLZ#vJR
6r!
Y ~\@
(ListUser.class); 4
AZ~<e\
TP o%zZo
private UserService userService; z%$ E6Im
oFM\L^Y?$$
private Page page; psyxNM=dN#
7ksh%eV
privateList users; IhnHNY]<g
LOQoi8j
/* c.-h'1
* (non-Javadoc) A}WRpsA9
* _a1 =?
* @see com.opensymphony.xwork.Action#execute() $2B_a
*/ ^ CVhV
publicString execute()throwsException{ cpvN
}G
Result result = userService.listUser(page); 9<u^.w
page = result.getPage(); KwK[)Cvv
users = result.getContent(); x{{QS$6v
return SUCCESS; !$Aijd s5
} ]T|9>o!
Xou1X$$z
/** )OQhtxK
* @return Returns the page. j(^ot001%v
*/ (Cjnf
a 2
public Page getPage(){ ^7MhnA
return page; n@n608
} #:C;VAAp
ASmMj;>UM
/** F x,08
* @return Returns the users. w}+#w8hu
*/ hoY.2 B _
publicList getUsers(){ ah<1&UG,
return users;
o&uO ]
} I@Zd<