Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 <PiO %w{
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 P)cEYk
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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 CW2)1%1iz
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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 `ZbFky{
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分页支持类: y/5GY,z%aL
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java代码: 'y=N_/+s
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package com.javaeye.common.util; N/ f7"~+`
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import java.util.List; /M+Du,
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publicclass PaginationSupport { =~k
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publicfinalstaticint PAGESIZE = 30; U`lK'..
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privateint pageSize = PAGESIZE; dt^h9I2O
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privateList items; ?^M,Mt
*yaS^k\
privateint totalCount; 0y6M;"&~E
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privateint[] indexes = newint[0]; *ziR &Fr!
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privateint startIndex = 0; eZaSV>27
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public PaginationSupport(List items, int
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y)U?.@
totalCount){ #c5jCy}n
setPageSize(PAGESIZE); fx(h fz
setTotalCount(totalCount); Pc_aEBq
setItems(items); D}q"^"#T
setStartIndex(0); "4;nnq
} 8!rdqI
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public PaginationSupport(List items, int pF4Z4?W
u8]FJQ*\6+
totalCount, int startIndex){ h693TS_N
setPageSize(PAGESIZE); <^'{=A>
setTotalCount(totalCount); o6d x\
setItems(items); t*=[RS*
setStartIndex(startIndex); ATl?./T u
} @p
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public PaginationSupport(List items, int \ l#eW
x
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totalCount, int pageSize, int startIndex){ nuXL{tg6
setPageSize(pageSize); XzHR^^;u"*
setTotalCount(totalCount); USEb} M`
setItems(items); 8 {V9)U
setStartIndex(startIndex); Y.\x.Hg
} ;~EQS.Qp
,VHqZ'6
publicList getItems(){ )63
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return items; 3o%vV*
} P"8Ix
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publicvoid setItems(List items){ /{\ /e"5
this.items = items; U}RBgPX!
} m{/(
3
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publicint getPageSize(){ `8ac;b
return pageSize; W<r<K=`5P
} <qwf"Ey
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publicvoid setPageSize(int pageSize){ (Jk&U8y
this.pageSize = pageSize; .9rYBy
} YV<y-,Io
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publicint getTotalCount(){ LE\=Y;%
return totalCount; }OpUG
} "`$,qvNN
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publicvoid setTotalCount(int totalCount){ uiVNz8H
if(totalCount > 0){ V4:/LNq_]
this.totalCount = totalCount; Y~WdN<g
int count = totalCount / BDB*>y7(
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pageSize;
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if(totalCount % pageSize > 0)
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count++; 2DQVl
indexes = newint[count]; -&Z!b!jN
for(int i = 0; i < count; i++){ eDJnzh83
indexes = pageSize * X0G,tl
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i; N1a]y/
} gV2vwe
}else{ 2:*15RH3
this.totalCount = 0; m,k0 h%
} r5}p .
} um.ZAS_kmc
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publicint[] getIndexes(){ .a.HaBBV
return indexes; rH3U;K!
} ~"#0rPT
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publicvoid setIndexes(int[] indexes){ ,/\`Rc^n
this.indexes = indexes; oY)eN?c
} o,*m,Qc
/Y#8.sr
publicint getStartIndex(){ ;@wa\H[3v2
return startIndex; )A8#cY!<
} b`jR("U
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publicvoid setStartIndex(int startIndex){ ;m]V12
if(totalCount <= 0) ZcN0:xU
this.startIndex = 0; |+Y-i4t
elseif(startIndex >= totalCount) _:r8UVAT.
this.startIndex = indexes ,:?ibE=
J,=K1>8s
[indexes.length - 1]; hX.cdt_?
elseif(startIndex < 0) /5NWV#-
this.startIndex = 0; 'Z{`P0/^o`
else{ 4uXGpsL
this.startIndex = indexes Dvg'
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[startIndex / pageSize]; N]P~`)
} gP%<<yl
} 3:,%>#"
!> sA.L&=
publicint getNextIndex(){ X-\$<DiJGv
int nextIndex = getStartIndex() + 9q`Ewj R
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pageSize; e>MtDJ5
if(nextIndex >= totalCount) 2{ F-@}=
return getStartIndex(); |]&3*%b@
else LJeq{Z
return nextIndex; #{6VdWZ
} T|~5dZL
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publicint getPreviousIndex(){ LIDi0jbrq
int previousIndex = getStartIndex() - S5).\1m h[
YWIA(p8Qkk
pageSize; iJ{axa &
if(previousIndex < 0) ]Jswxw
return0;
b] 5dBZ(
else {"p ~M7
return previousIndex; lQIg0G/3
} mB`HPT
D?KLV_Op
} NS[ Z@@
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抽象业务类 OLG)D#m(4/
java代码: rmjuNy=(
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/** Ftyxz&-4$p
* Created on 2005-7-12 zZ[kU1Fyv
*/ `{#""I^_
package com.javaeye.common.business; AF:_&gF
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import java.io.Serializable; =c6d$
import java.util.List;
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import org.hibernate.Criteria; rCo}^M4Pb
import org.hibernate.HibernateException; b'O/u."O
import org.hibernate.Session; z(A60b}
import org.hibernate.criterion.DetachedCriteria; fHaF9o+/b
import org.hibernate.criterion.Projections; (Nzh1ul\}
import Ic3a\FTr\
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org.springframework.orm.hibernate3.HibernateCallback; K"l~bFCZ8
import 4zs0+d+
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org.springframework.orm.hibernate3.support.HibernateDaoS u&*[
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upport; }oD^tU IK
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import com.javaeye.common.util.PaginationSupport; Ja1 `S+
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public abstract class AbstractManager extends CV[ 9i
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HibernateDaoSupport { ZKI8x1>Iq
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privateboolean cacheQueries = false; D&fOZVuqZ
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privateString queryCacheRegion; 56Lxr{+X
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publicvoid setCacheQueries(boolean "C}<umJ'
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cacheQueries){ (%6fZ
this.cacheQueries = cacheQueries; O}C*weU
} 6EY\
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publicvoid setQueryCacheRegion(String s58dHnj5+
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queryCacheRegion){ %Ja0:e
this.queryCacheRegion = I?1BGaAA
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queryCacheRegion; /sYr?b!/<6
}
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publicvoid save(finalObject entity){ l>|scs;TI
getHibernateTemplate().save(entity); ~;b}_?%o
} 9<&*iIrM
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publicvoid persist(finalObject entity){ fbM>jK
getHibernateTemplate().save(entity); n:a~=^IV
} MHp:".1
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publicvoid update(finalObject entity){ |Fx *,91
getHibernateTemplate().update(entity); xm=Gt$>.o
} sw9ri}oc
id,' + <
publicvoid delete(finalObject entity){ X#by Dg
getHibernateTemplate().delete(entity); |"}7)[BW}
} 8@doKOA~T
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publicObject load(finalClass entity, jp"Q[gR##
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finalSerializable id){ ]*MVC/R,
return getHibernateTemplate().load %O!xrA{
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(entity, id); #t2N=3dOj
} Z molL0y
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publicObject get(finalClass entity, ;wJe%Nw?
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finalSerializable id){ e2fv%
return getHibernateTemplate().get X!{K`~DRX
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(entity, id); eKuF7Oo
} Sz|kXk6&9
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publicList findAll(finalClass entity){ %Cj_z
return getHibernateTemplate().find("from `'3&tAy
w)&4i$Lk6
" + entity.getName()); 8,F|*YA
} Aua}.Fl,
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publicList findByNamedQuery(finalString $KT)Kz8tF
)zy;!
namedQuery){ <l!:#u
return getHibernateTemplate tZx}/&m-
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().findByNamedQuery(namedQuery); @+nCNXK
} ]H{*Z3S
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publicList findByNamedQuery(finalString query, 0s Jp,4Vv
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finalObject parameter){ YvuE:ia
return getHibernateTemplate V60"j(
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().findByNamedQuery(query, parameter); a;Pn.@NVq
} '.N}oL<gP
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publicList findByNamedQuery(finalString query, S~H>MtX(<
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finalObject[] parameters){ x|AND]^Q
return getHibernateTemplate .nNZdta&=
$y.0h(
().findByNamedQuery(query, parameters); mJ(ElDG
} 7;Lv_Y"b
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publicList find(finalString query){ g'w"U9tjO
return getHibernateTemplate().find m<k6oev$
T.')XKP)1N
(query); 3*\Q]|SI!
} KJS-{ed
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publicList find(finalString query, finalObject z`$c4p6G6
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parameter){ Qv'x+GVW]
return getHibernateTemplate().find Q}l~n)=
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(query, parameter); L^Q;M,.c;
} `:EhYj.
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public PaginationSupport findPageByCriteria ;!=i|"PG
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(final DetachedCriteria detachedCriteria){ ?*xH
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return findPageByCriteria ypGt6t(;
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); <]DUJuF-M
} ~#P]NWW%.
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public PaginationSupport findPageByCriteria ^A=tk!C
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(final DetachedCriteria detachedCriteria, finalint .p o,.}
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startIndex){ mvTp,^1
return findPageByCriteria Jd v;+HN[
'3sySsD&O
(detachedCriteria, PaginationSupport.PAGESIZE, h<>yzr3fN
vGPsjxk&
startIndex); wD$UShnm9-
} =O8>[u;
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public PaginationSupport findPageByCriteria 8HZ+r/j
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(final DetachedCriteria detachedCriteria, finalint +?Cy8Ev?
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pageSize, );q~TZ[Do
finalint startIndex){ .oLV\'HAR
return(PaginationSupport) W[j,QU
rev*G:
getHibernateTemplate().execute(new HibernateCallback(){ %yjD<2J;
publicObject doInHibernate v[8+fd)}S
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(Session session)throws HibernateException { ITn PF{N
Criteria criteria = 3Z me?o*bY
f{[0;qDJ
detachedCriteria.getExecutableCriteria(session); IFS_DW
int totalCount = R?9x!@BV
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((Integer) criteria.setProjection(Projections.rowCount f^"pZS
nu~]9~)I
()).uniqueResult()).intValue(); :-Py0{s
criteria.setProjection dVHbIx
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(null); :{lP9%J-
List items = +w?R4Sxjn
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criteria.setFirstResult(startIndex).setMaxResults [2Nux0g
Kdp($L9r
(pageSize).list(); _'L16@q
PaginationSupport ps = 0%}*Zo(e+
J>nBTY,_<
new PaginationSupport(items, totalCount, pageSize, `JPkho
Vq{3:QBR
startIndex); $6D*G-*8
return ps; NV9JMB{q
} K5XW&|tY!
}, true); Av5:/c.B
} MpZ\j
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public List findAllByCriteria(final y35~bz^2
a@qc?
DetachedCriteria detachedCriteria){ >{:hadUH
return(List) getHibernateTemplate dY~z6bT
p)?6#~9$
().execute(new HibernateCallback(){ EEL3~H{(
publicObject doInHibernate S7PWP<9
sO6=w%l^
(Session session)throws HibernateException { yrfV&C%=n
Criteria criteria = r@Jy*2[-Jq
Yb/*2iWX
detachedCriteria.getExecutableCriteria(session); 9`Fw}yAt
return criteria.list(); s<k2vbhI
} vPz7*w
}, true); x(eX.>o\
} ^IIy>
v}V[sIs}
public int getCountByCriteria(final nM b@
B
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DetachedCriteria detachedCriteria){ "opMS/a"7
Integer count = (Integer) u{\'/c7G
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getHibernateTemplate().execute(new HibernateCallback(){ zhFm2
publicObject doInHibernate fbOqxF"?we
)=29Hm"
(Session session)throws HibernateException { rZaO^}u]
Criteria criteria = Z
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detachedCriteria.getExecutableCriteria(session); -,p=;t#(
return ZcyGLg0I
7>F{.\Z
criteria.setProjection(Projections.rowCount +>vKI8g*RH
[x>Ju&))$
()).uniqueResult(); 9CeR^/i
} 6:Z8d%Z
}, true); 4m1r@
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return count.intValue(); KAFR.h:p9
} NE8W--Cg|
} tB,(12@W
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用户在web层构造查询条件detachedCriteria,和可选的 %KT}Map
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 oR=i5lAU
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PaginationSupport的实例ps。 Q^rR }Ws
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ps.getItems()得到已分页好的结果集 %'H DP3
ps.getIndexes()得到分页索引的数组 I_u/
ps.getTotalCount()得到总结果数 N6}/TbfAR
ps.getStartIndex()当前分页索引 jj2\;b:a0
ps.getNextIndex()下一页索引 ;'uQBx}
ps.getPreviousIndex()上一页索引 %sr- xE
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 F1L[3D^-
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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 TI<
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一下代码重构了。 Nq6'7'x
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我把原本我的做法也提供出来供大家讨论吧: !ou#g5Q@z
~,HFd`
首先,为了实现分页查询,我封装了一个Page类: !sm/BsmL7T
java代码: !V37ePFje
1Qf}nWy
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/*Created on 2005-4-14*/ gtA34iw
package org.flyware.util.page; UDg's
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/** 3Hom0g,V4
* @author Joa 1I9v`eT4
* .w.:o2L
*/ LJ(WU)CPc
publicclass Page {
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x [FLV8`b|
/** imply if the page has previous page */ <s'de$[
privateboolean hasPrePage; !-f Bw
*n? 1C"l
/** imply if the page has next page */ @ivd|*?k0
privateboolean hasNextPage; L9D`hefz
FI$:R
/** the number of every page */ i
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privateint everyPage; lZ\8W^
|/*Pimk
/** the total page number */ F`nQS&y
privateint totalPage; Z nc(Q
J/?Nf2L4
/** the number of current page */ a[O6xA%
privateint currentPage; 1q;v|F
Nujnm$!,Q
/** the begin index of the records by the current =#b@7Yw:
c~Ka) dF|
query */ 7w/IHM L
privateint beginIndex; #dA$k+3
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v~P,OP("c
/** The default constructor */ o|(5Sr&H
public Page(){ Dsg>~J'
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} d,"LZ>hNY*
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/** construct the page by everyPage z*eBjHbF
* @param everyPage smQ^(S^
* */ EiW|+@1
public Page(int everyPage){ /fr> Fd
this.everyPage = everyPage; u]J@65~'b
} *x"80UXL
;Ba%aaHl
/** The whole constructor */ LwH#|8F
public Page(boolean hasPrePage, boolean hasNextPage, w
)R5P[b
!Lf<hS^
$7S"4rou
int everyPage, int totalPage, ??rS h Mu
int currentPage, int beginIndex){ &v{Ehkr*
this.hasPrePage = hasPrePage; 5AYOM=O]t
this.hasNextPage = hasNextPage; SiratkP9n7
this.everyPage = everyPage; iQwQ5m!d &
this.totalPage = totalPage; x *eU~e_jP
this.currentPage = currentPage; \c=I!<9
this.beginIndex = beginIndex; +2~kHrv
} ,kN;d}bg
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/** /d8o*m'bu!
* @return !~@GIr
* Returns the beginIndex. UNdD2Fd9
*/ Y`|+sND
publicint getBeginIndex(){ 5'~_d@M
return beginIndex; _kj]vbG^;
} "s*-dZO
J!6FlcsZm
/** RLB3 -=9t
* @param beginIndex *T|B'80
* The beginIndex to set. gE-y`2SU
*/ 0+1wi4wy/
publicvoid setBeginIndex(int beginIndex){ 1uw#;3<L
this.beginIndex = beginIndex; E9HMhUe
} > VG
H",B[
YK
/** &NE e-cb[
* @return X%1TsCKMj
* Returns the currentPage. rH+OXGoB
*/ 3FEJ
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publicint getCurrentPage(){ b'H'QY
return currentPage; RpHlq
} ;?-AFd\i
o`?rj!\
/** woYD &Oml
* @param currentPage ie}OZM
* The currentPage to set. +]db-
*/ }I"C4'(a
publicvoid setCurrentPage(int currentPage){ y7R#PkQ~
this.currentPage = currentPage; ^NW[)Dq1<
} %\As
\{,TpK.
/** W.7rHa
* @return {|+Y;V`
* Returns the everyPage. '=\}dav!
*/ h~MV=7
lE
publicint getEveryPage(){ Y Y:BwW:
return everyPage; f&
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}
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/** )s2] -n}W
* @param everyPage 0&.CAHb}
* The everyPage to set. #x%'U}sF
*/ 90}{4&C.^
publicvoid setEveryPage(int everyPage){ QFyL2Xes/
this.everyPage = everyPage; mCtS_"W
} X'9.fKp
X|M!Nt0'
/** E-MPFL
* @return +jN}d=N-
* Returns the hasNextPage. +Q*`kg'
*/ !,WGd|oJ
publicboolean getHasNextPage(){ <P9fNBGa
return hasNextPage; Y4T")
} e_vsiT
%B3~t>
/** 2EY"[xK|
* @param hasNextPage ?HZp@&
* The hasNextPage to set. .=_p6_G
*/ eE;tiX/
publicvoid setHasNextPage(boolean hasNextPage){ -wlj;U
this.hasNextPage = hasNextPage; 0ju1>.p
} e5=d
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<t%gl5}|
/** 7*'/E#M
* @return MfTLa)Rz
* Returns the hasPrePage. #c!:&9oU
*/ Nz{dnV{&x;
publicboolean getHasPrePage(){ rCyb3,W
return hasPrePage; OI R5QH
} 3KLUH=)P
d{
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/** yTaMlT|
* @param hasPrePage -H1=N
* The hasPrePage to set. @WJ;T= L
*/ oL4W>b )
publicvoid setHasPrePage(boolean hasPrePage){ We+rFk1ddt
this.hasPrePage = hasPrePage; -F[8ZiZ
} ^s,3*cAU
yr]ja-Y
/** \}-4(Xdaq
* @return Returns the totalPage. y)f.ON36I
* g14*6O:
*/ 1I Yip\:lS
publicint getTotalPage(){ _iwG'a[`
return totalPage; 4"@<bKx
} aCQtE,.
NgNGq\!
/** Hg+<GML
* @param totalPage MsB>3
* The totalPage to set. Nk~}aj
*/ ` ]|X_!J-
publicvoid setTotalPage(int totalPage){ UuG%5 ZC
this.totalPage = totalPage; F[qXIL)
} t2&kGf"
:WhJDx`j
} sW^M
]
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];r!
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:\TMm>%q
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 jiI=tg;
s"(RdJ-,
个PageUtil,负责对Page对象进行构造: :XKYfc_y
java代码: $+gQnI3w
Ht`fC|E
/iW+<@Mas
/*Created on 2005-4-14*/ ]kh]l8t ^
package org.flyware.util.page; Rq4;{a/j
~NGM6+9
import org.apache.commons.logging.Log; rOIb9:
import org.apache.commons.logging.LogFactory; i4C{3J^
?2<QoS
/** ",r
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* @author Joa G
hM
* #h!+b
*/ }"Y<<e<z:
publicclass PageUtil { |jsI-?%8J
verI~M$v{
privatestaticfinal Log logger = LogFactory.getLog kuY^o,u-1e
YMGy-]!o
(PageUtil.class); X<ex
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;W|kc</R*
/** UhB+c
* Use the origin page to create a new page ?7\V)$00(&
* @param page UG1<Xfu|
* @param totalRecords D#jwI,n}x
* @return 9#E *o~1
*/ b[%@3 }E
publicstatic Page createPage(Page page, int ZlV
e8,_"_1:F
totalRecords){ "tEp8m
return createPage(page.getEveryPage(), uJ`N'`Z
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page.getCurrentPage(), totalRecords); ulR yt^bx|
} .EYL
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/** z$ ^d_)
* the basic page utils not including exception So5/n7
7o4E_ .*
handler O{ :{P5
* @param everyPage Y A.&ap
* @param currentPage 5-dt0I@<
* @param totalRecords g&RpE41x
* @return page "2e3 <:$
*/ l;$F[/3a
publicstatic Page createPage(int everyPage, int "$BkO[IS
|N,^*xP(6
currentPage, int totalRecords){ 4+olyBht
everyPage = getEveryPage(everyPage); pEB3qGA
currentPage = getCurrentPage(currentPage); 8X;?fjl`"
int beginIndex = getBeginIndex(everyPage, !~^2Mu(X
g |)>65v
currentPage); gx\V)8Zr
int totalPage = getTotalPage(everyPage, MmJMx
\Z*:l(
totalRecords); jAQ{H
boolean hasNextPage = hasNextPage(currentPage, zK0M WyXO
%PW-E($o<
totalPage); :?f<tNU$
boolean hasPrePage = hasPrePage(currentPage); k|fM9E
U$:^^Zt`B
returnnew Page(hasPrePage, hasNextPage, [*%lm9 x
everyPage, totalPage, l|g*E.:4
currentPage, lp*5;Ls'q
NF$6yv9C
beginIndex); %Tp9GGt
} #rHMf%0
OPvPP>0*8
privatestaticint getEveryPage(int everyPage){ mQj# \<*
return everyPage == 0 ? 10 : everyPage; 288mP]a(v_
} mF
gqM:
dJ"44Wu+J
privatestaticint getCurrentPage(int currentPage){ r*HSi.'21
return currentPage == 0 ? 1 : currentPage; cT(nKHL
} qw+7.h#V
YB*)&@yx
privatestaticint getBeginIndex(int everyPage, int 5{H)r
wXNng(M7
currentPage){ )St0}?I~
return(currentPage - 1) * everyPage; p{?duq=
} fb
f&bJT
Q}#4Qz~n
privatestaticint getTotalPage(int everyPage, int 8%4;'[UV
Y58H.P
totalRecords){ 5%'ybh)@
int totalPage = 0; 74_?@Z(
s$y_(oU,D
if(totalRecords % everyPage == 0) '{`KYKLP+
totalPage = totalRecords / everyPage; j)ic7b
else d /jx8(0
totalPage = totalRecords / everyPage + 1 ; P IG,a~
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return totalPage; >A )Sl'
} .)*&NY!nsl
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privatestaticboolean hasPrePage(int currentPage){ c{'Z.mut
return currentPage == 1 ? false : true; 1dD%a91
} MpKXC
6@aH2+4+
privatestaticboolean hasNextPage(int currentPage, CI+)0=`<1B
x.t<@y~
int totalPage){ ;apLMMsWC
return currentPage == totalPage || totalPage == g.\b@0Uy'
AB
$N`+&
0 ? false : true; (~@.9&cBD
} S1k*"><
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d 6Y9D=O
} %<~Ewno T
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II^Rp],>
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上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 QXI~Toddj
#h.N#{9
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 Eq@sU?j
GS*O{u
做法如下: gvVy0nJI~
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 Gn7\4,C
mq{Z
Q'
的信息,和一个结果集List: )t~ad]oM
java代码: Tw \@]fw
HubG>]
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/*Created on 2005-6-13*/ ~vP_c(8f
package com.adt.bo; f*@
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qX&+
import java.util.List; .0nT*LF
`LH 9@Z{
import org.flyware.util.page.Page; t:dvgRJt*
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/** [voc_o7AI
* @author Joa S|d /?}C|e
*/ d%@0xsU1
publicclass Result { VK4UhN2
l="(Hp%b
private Page page; qY&(O`?m&
Cpzd k~+H
private List content; tzl,r"k3
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/** %B&O+~
* The default constructor 4FnePi~i
*/ DKo6lP`
public Result(){ qV=O;
super(); )~P<ruk>,C
} ,!SbH
4JBfA,
/** oe6Ex5h
* The constructor using fields /&?ei*z
* va~:Ivl-)
* @param page 0r@LA|P
* @param content r<]^.]3zj
*/ Y&VypZ"G>
public Result(Page page, List content){ ~+6#4<M.~
this.page = page; C&q}&=3r
this.content = content; jKP75jm
} .yzXw8~S
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/** ?@A@;`0Y
* @return Returns the content. @#"K6
*/ :A#'8xE/
publicList getContent(){ 6o#J
return content; ;8F6a:\v
} <)cmI .J3
>$<Q:o}^
/** zBrIhL]95
* @return Returns the page. tIA)LF
*/ <q MX,h2
public Page getPage(){ NVVAh5R
return page; 3F6'3NvVc2
} F0m[ls$
C#&b`
/** w6 Y+Y;,'f
* @param content 8}z PDs
* The content to set. 'o_ RC{k2"
*/ %[,^2s
public void setContent(List content){ O[ans_8
this.content = content; E?0RR'
} _#<l -R`
acpc[^'
/** \ }-v
* @param page yYC\a7Al4
* The page to set. DL_M#c`<
*/ hHt.No
publicvoid setPage(Page page){ ;r;>4+zn\
this.page = page; I
tn?''~;
} Y5>'(A>
} LQ$dT#z2A
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2. 编写业务逻辑接口,并实现它(UserManager, jaTCRn3|<
7")&njQ/x
UserManagerImpl) .bMU$ O1
java代码: ?$7$ # DX
~ "~uXNd
%MfT5*||f
/*Created on 2005-7-15*/ BD ,3JDqT
package com.adt.service; 51%<N\>/4
D@mqfi(x
import net.sf.hibernate.HibernateException; t/"9LMKs?
,"5p=JX`
import org.flyware.util.page.Page; <RkJ7Z^
is-{U?-
import com.adt.bo.Result; v2#qs*sW8
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/** *
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* @author Joa el0W0T
*/ (7aE!r\Ab
publicinterface UserManager { Bq:: 5,v
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public Result listUser(Page page)throws =1kjKE !
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HibernateException; $r)nvf`\
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} {QLqf
)3_g&&
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Kib?JRYt
l\-(li
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java代码: YwM;G
g3
E?f*Z{~,
M7lMOG(\
/*Created on 2005-7-15*/ @l2AL9z$m>
package com.adt.service.impl; "2/VDB4!FG
1<9m^9_ro
import java.util.List; -Kf'02
+%RXV~
import net.sf.hibernate.HibernateException; `!T6#6h
YI?y_S
import org.flyware.util.page.Page; Y6@A@VJ
import org.flyware.util.page.PageUtil; 5h(]S[Zf3
w3IU'(|G
import com.adt.bo.Result; gs|%3k |
import com.adt.dao.UserDAO; cXokq
import com.adt.exception.ObjectNotFoundException; -1u N
Z{0
import com.adt.service.UserManager; Z.0^:rVp~
>G+?X+9
/** *SZ*S%oS3
* @author Joa 6{I5 23g
*/ ZGOI8M]@
publicclass UserManagerImpl implements UserManager { tU7eW#"w
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private UserDAO userDAO; SY2B\TV
8:A6Ew&\]O
/** mY1$N}8fm
* @param userDAO The userDAO to set. - r82'3]
*/ ~#~Kxh
publicvoid setUserDAO(UserDAO userDAO){ dkf?lmC+M
this.userDAO = userDAO; K`1\3J)
} WaWx5Fx+
9X{aU)"omQ
/* (non-Javadoc) MhB kr{8
* @see com.adt.service.UserManager#listUser >!YI7)
#6JCm!s
(org.flyware.util.page.Page) N1!|nS3w
*/ D &wm7,
public Result listUser(Page page)throws 3C8'@-U
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HibernateException, ObjectNotFoundException { x2TCw
int totalRecords = userDAO.getUserCount(); j:,*Liz
if(totalRecords == 0) 9W7H",wR
throw new ObjectNotFoundException b_=k"d
S?=2GY
("userNotExist"); uoKC+8GA
page = PageUtil.createPage(page, totalRecords); aARm nV
List users = userDAO.getUserByPage(page); EY!aiH6P
returnnew Result(page, users); 8DLMxG
} ,k@fXoW
Nr7MSFiL
} p<6pmW3
Fk
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TaB35glLY
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其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 H1=R(+-s
uBs[[9je(
询,接下来编写UserDAO的代码: ~GS`@IU}
3. UserDAO 和 UserDAOImpl:
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java代码: {{=7 mbc
QkzPzbF"
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/*Created on 2005-7-15*/ YrgwR
package com.adt.dao; G0//P
.#
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import java.util.List; diqG8KaK
Qo{^jDe,c*
import org.flyware.util.page.Page; W?/7PVGv5h
&ze'V
, :
import net.sf.hibernate.HibernateException; d|6*1hby
$-
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/** "$:nz}
* @author Joa ^ tm,gh
*/ e v?Hz8Q;(
publicinterface UserDAO extends BaseDAO { ({zp$P}
;nv4lxm
publicList getUserByName(String name)throws :ZU
JCaT^KLz
HibernateException; "Rs^0iT7>
K=Fcy#,f
publicint getUserCount()throws HibernateException; sbNCviKP
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IV
publicList getUserByPage(Page page)throws +|(
eP_
x_(B7ob
HibernateException; NCSb`SC:
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} !OWV* v2
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CWI(Q`((>
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java代码: <6n(a)L1
C2eei're
j|HOry1E &
/*Created on 2005-7-15*/ 'n.eCdj
package com.adt.dao.impl; 8 s:sMU:Q
+5);"71
import java.util.List; )X| uOg&|
{u46m
import org.flyware.util.page.Page; -oe&1RrdVg
D@d/O
import net.sf.hibernate.HibernateException; ycCEXu2F
import net.sf.hibernate.Query; Te!q(;L`4
Z^`>;n2
import com.adt.dao.UserDAO; G*Z4~-E4*
Dw6Q2Gnv
/** |yN7#O-D
* @author Joa le|e 4f*+
*/ d%4!d_I<
public class UserDAOImpl extends BaseDAOHibernateImpl U4zyhj
T92k"fBY
implements UserDAO { ZZFa<AK4
W/{HZ< :.
/* (non-Javadoc) +l&ZN\@0X
* @see com.adt.dao.UserDAO#getUserByName WZ"x\K-;
r#3_F=xL5
(java.lang.String) m]Z&
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*/ LfrS:g
publicList getUserByName(String name)throws &HZ"<y{j
7PP76$
HibernateException { .wS' Xn&
String querySentence = "FROM user in class xk.\IrB_
}3^t,>I=,6
com.adt.po.User WHERE user.name=:name"; Scs \nF2
Query query = getSession().createQuery B7T(9Tj+Fh
A'6>"=ziP
(querySentence); 9)T;.O
query.setParameter("name", name); i>q]U:U
return query.list(); g;eMsoJG
} i v&:X3iB
~n|*-rca
/* (non-Javadoc) eH=lX9
* @see com.adt.dao.UserDAO#getUserCount() 3MiNJi#=2
*/ 3@s|tm1
publicint getUserCount()throws HibernateException { q}tLOVu1
int count = 0; xQ7>u-^
String querySentence = "SELECT count(*) FROM . v0 .wG
RP z0WP
user in class com.adt.po.User"; SgFyv<6>:
Query query = getSession().createQuery Y-@K@Zu]?
B]InOlc47
(querySentence); &FIPEe#n
count = ((Integer)query.iterate().next ^0A'XCULG
mTYEK4}
()).intValue(); r/+<_3
return count; (?I8/KYR
} #U(dleT8
6
}qNH29
/* (non-Javadoc) 70a7}C\/o
* @see com.adt.dao.UserDAO#getUserByPage
"+r8izB
7oh6G
(org.flyware.util.page.Page) ]6W#P7
*/ B.;/N220P
publicList getUserByPage(Page page)throws -`FTWH
KE&Y~y8O\
HibernateException { \ d+&&ns
String querySentence = "FROM user in class mn?<
Zz
X9#Od9cNaC
com.adt.po.User"; 'X"@C;q
Query query = getSession().createQuery Mfuw y
92bvmP*o4
(querySentence); 9eH(FB
query.setFirstResult(page.getBeginIndex()) 6|rqsk
.setMaxResults(page.getEveryPage()); 2zh?]if
return query.list(); b,$H!V*
} #ZRQVC; b;
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}
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>QU1_'1r
5L"{J5R}
g(>;Z@Y
/H^=`[Mr
至此,一个完整的分页程序完成。前台的只需要调用 j{0_K+B
8 POrD8B
userManager.listUser(page)即可得到一个Page对象和结果集对象 J,_I$* _0
$j)Er.!9|R
的综合体,而传入的参数page对象则可以由前台传入,如果用 %f#3;tpC8
}>6=(!
webwork,甚至可以直接在配置文件中指定。 ,/C<GFae
A+69_?B
TH
下面给出一个webwork调用示例: G5 Y 8]N
java代码: r,A750P^
b-@6w(j
`)*
/*Created on 2005-6-17*/ x4pl#~Su
package com.adt.action.user; LwZBM#_g
wt? 8-_
import java.util.List; gk"S`1>
3YR6@*!f/
import org.apache.commons.logging.Log; Y<#WC#3=
import org.apache.commons.logging.LogFactory; w6'o<=
import org.flyware.util.page.Page; nMNAn}~*M
sFC&DTb?
import com.adt.bo.Result; j,8*Z~\5
import com.adt.service.UserService; WXp=>P[
import com.opensymphony.xwork.Action; dMp7 ,{FhF
@c,}\"(
/** J@=1zL
* @author Joa KCGs*kp>
*/ /iQ}DbtRb
publicclass ListUser implementsAction{ & G@(f=
'sn%+oN
privatestaticfinal Log logger = LogFactory.getLog #U{^L{1Gx
3o%JJIn&
(ListUser.class); 3x#=@i
VTa?y
private UserService userService; qN1(mxa.?
vHcB^Z
private Page page; S&Q1