Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 ]F{F+r
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根
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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 F ,;B
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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 "lVbla4b
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分页支持类: QbJE+m5
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java代码: R+*-i+]Q#7
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package com.javaeye.common.util; sB@9L L]&|
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import java.util.List; i}L*PCP
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publicclass PaginationSupport { A3Xfu$[u
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publicfinalstaticint PAGESIZE = 30; :R'={0Jg
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privateint pageSize = PAGESIZE; \b;z$P\+*
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privateList items; cy64xR BB
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privateint totalCount; M7fPaJKL
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privateint[] indexes = newint[0]; Y1wH_!%b
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privateint startIndex = 0; pzT,fmfk
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public PaginationSupport(List items, int L9]y~[R:
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totalCount){ 'u#c_m!9
setPageSize(PAGESIZE); 5oe{i/#di
setTotalCount(totalCount); {zI>"%$u
setItems(items); .~a.mT
setStartIndex(0); < ZG!w^
} \ nUJ)w
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public PaginationSupport(List items, int WCYVon bg"
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totalCount, int startIndex){ % !>@m6JK
setPageSize(PAGESIZE); s7(1|}jh
setTotalCount(totalCount); v=_Ds<6n
setItems(items); en"\2+{Cg
setStartIndex(startIndex); }U^iVq*
} Xf;_r+;
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public PaginationSupport(List items, int jA? 7>"|
yR% l[/ X
totalCount, int pageSize, int startIndex){ 6T5\zInd
setPageSize(pageSize); #z61I"kU
setTotalCount(totalCount); sB*!Nf^y
setItems(items); v'Pbx
setStartIndex(startIndex); Nh01NY;
} rA|&G'
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publicList getItems(){ ,`8:@<e
return items; E#E&z (G2
} ^U6VJ(58P
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publicvoid setItems(List items){ U]&/F{3
im
this.items = items; K1=j7
} kpRk.Q*
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publicint getPageSize(){ ^)o#/"JA
return pageSize; k]9y+WC2
} }ww`Y
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publicvoid setPageSize(int pageSize){ ?jU 3%"
this.pageSize = pageSize; OWp`Wat
} dbg%n 0h
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publicint getTotalCount(){ R_=fH\c;
return totalCount; _ mgu
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} p@?ud%
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publicvoid setTotalCount(int totalCount){ F;MACu;x
if(totalCount > 0){ ,ZZ5A;)
this.totalCount = totalCount; sD9OV6^{?K
int count = totalCount / vs{VRc
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pageSize; ,va2:V
if(totalCount % pageSize > 0) ~uG/F?= Q:
count++; q#F+^)DD [
indexes = newint[count]; hT%
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for(int i = 0; i < count; i++){ ~wu\j][2
indexes = pageSize * QJ%N80
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i; l>6p')F!
} t^=S\1"R\
}else{ ,uD}1
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this.totalCount = 0; [[O4_)?el
} k_nQmU>
} 7e[&hea
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publicint[] getIndexes(){ jw)c|%r>
return indexes; `*xSn+wL`_
} <Wd_m?z
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publicvoid setIndexes(int[] indexes){ (/S6b
this.indexes = indexes; 9RC:-d;;_
} FjW%M;H
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publicint getStartIndex(){ I/zI\PP,
return startIndex; #@F
} RLO<5L
Ev T"+;9/p
publicvoid setStartIndex(int startIndex){ 6A4{6B
if(totalCount <= 0) R8Dn
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this.startIndex = 0; 0S\HO<~k
elseif(startIndex >= totalCount) )>N=B 2P
this.startIndex = indexes lI3d
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p::`1
[indexes.length - 1]; @vO~'Xxq!
elseif(startIndex < 0) Hn]6re
this.startIndex = 0; ItE)h[86
else{ @>F`;'_*z
this.startIndex = indexes !>fi3#Fi
[7l5p(=
[startIndex / pageSize]; N_p^DP
} 8\bZ?n#dn
} N.vkM`Z
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publicint getNextIndex(){ Pa{bkr
int nextIndex = getStartIndex() + ?{~. }Vn
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pageSize;
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if(nextIndex >= totalCount) PI)uBA;
return getStartIndex(); BPu>_$C
else n>YgL}YZ?
return nextIndex; 9 LUk[V
} +WvW#wpH
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publicint getPreviousIndex(){ ig'4DmNC
int previousIndex = getStartIndex() - ,]4.|A_[Rq
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pageSize; d3 p;[;`
if(previousIndex < 0) D7C%Y^K]>E
return0; 7H. HiyppW
else 6W'2w?qj?4
return previousIndex; CWkAc5
} 9abn6S(XpJ
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} uvA 2`%T/
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抽象业务类 nN(Q}bF
java代码: ;zo?o t/
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/** 9!wm`'G8
* Created on 2005-7-12 ,]=Qgn
*/ }9?fb[]
package com.javaeye.common.business; .-:6L2
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import java.io.Serializable; 4OdK@+-8U
import java.util.List; QezDm^<
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import org.hibernate.Criteria;
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import org.hibernate.HibernateException; 7P DD
import org.hibernate.Session; ^j'vM\^`ml
import org.hibernate.criterion.DetachedCriteria; tUs{/Je
import org.hibernate.criterion.Projections; [~ |e:
import gR{.0e
(<#Ns W!z
org.springframework.orm.hibernate3.HibernateCallback; #J4,mFMr
import "#`c\JuR]
}q~xr3#
org.springframework.orm.hibernate3.support.HibernateDaoS MP`WU} 2
_ 3>|1RB
upport; m} nA-*
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import com.javaeye.common.util.PaginationSupport; G$
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public abstract class AbstractManager extends Gp))1b';
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HibernateDaoSupport { &?7+8n&+
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privateboolean cacheQueries = false; XcQ'(
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privateString queryCacheRegion; .:jfNp~jt
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publicvoid setCacheQueries(boolean FZtILlw
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cacheQueries){ D\V
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this.cacheQueries = cacheQueries; N%`Eq@5
} 2BIOA#@t
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publicvoid setQueryCacheRegion(String "G!V?~;
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queryCacheRegion){ ;hp?wb
this.queryCacheRegion = '^.}5be&
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queryCacheRegion; #-u?+Nk/
} p uLQ_MNV
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publicvoid save(finalObject entity){ '|N9xLm
getHibernateTemplate().save(entity); CI6qDh6
} cX/["AM
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publicvoid persist(finalObject entity){ [8.w2\<?
getHibernateTemplate().save(entity); sp$W=Wu7
} GPnSdGLC
FzGla} )
publicvoid update(finalObject entity){ nLjo3yvV..
getHibernateTemplate().update(entity); h|Uy!?l
} K-*q3oh
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publicvoid delete(finalObject entity){ t Sf`
getHibernateTemplate().delete(entity); hgi9%>oUB
} c/E6}OWA
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publicObject load(finalClass entity, ua
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finalSerializable id){ +EBoFeeIG
return getHibernateTemplate().load ,*@6NK,.
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(entity, id); ,, G6L{&Z
} qZ7/d,w
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publicObject get(finalClass entity, nfMQ3KP
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finalSerializable id){ e
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return getHibernateTemplate().get )v67wn*1A
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(entity, id); hol54)7$3:
} \WVrn >%xu
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publicList findAll(finalClass entity){ (_ElM>
return getHibernateTemplate().find("from fw1 g;;E
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" + entity.getName()); PDcZno?
} 6 4da~SEn
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publicList findByNamedQuery(finalString b%<i&YY#
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namedQuery){ UC34AKm
return getHibernateTemplate Py8<db%
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().findByNamedQuery(namedQuery); X|7Y|0o
} 5E/z.5 q
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publicList findByNamedQuery(finalString query, O`hOVHDQ
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finalObject parameter){ @M-+-6+
return getHibernateTemplate 2|)3Ly9
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().findByNamedQuery(query, parameter); [S/]Vk|4
} ]64mSB
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publicList findByNamedQuery(finalString query, NVMhbpX6
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finalObject[] parameters){ \S@;>A<J
return getHibernateTemplate '%`Wy@
( {H5k''
().findByNamedQuery(query, parameters); p_jDnb#
} !ldb_*)h
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publicList find(finalString query){ 4l$(#NB<
return getHibernateTemplate().find HhaUC?JtSK
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(query); z2&SZ.mk
} +?~'K&@
u4=j!Zb8}
publicList find(finalString query, finalObject |wZ8O}O{E
F}A@H<?
parameter){ O=#FpPHrdw
return getHibernateTemplate().find g`!:7|&,_
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(query, parameter); DLkNL?a
} $@t-Oor;
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public PaginationSupport findPageByCriteria ubIGs|p2c
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(final DetachedCriteria detachedCriteria){ 1@kPl[`p'
return findPageByCriteria jl=<Q.Mm7
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); /GNRu
} $LZf&q:\]*
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public PaginationSupport findPageByCriteria tZ[Y~],F
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(final DetachedCriteria detachedCriteria, finalint $Tt@Xu
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startIndex){ *lg1iP{]
return findPageByCriteria Zg|z\VR
Z^>[{|lIA
(detachedCriteria, PaginationSupport.PAGESIZE, m u(HNj
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startIndex); W 0Q-&4
} a4X J0Tm
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public PaginationSupport findPageByCriteria |8h<Ls_
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(final DetachedCriteria detachedCriteria, finalint SG8H~]CO)
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pageSize, YZf<S:
finalint startIndex){ 1<^"OjQ
return(PaginationSupport) /J8AnA1
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getHibernateTemplate().execute(new HibernateCallback(){ /!UuGm
publicObject doInHibernate phUno2fH
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(Session session)throws HibernateException { Zbxd,|<|
Criteria criteria = -Xkdu?6Eh
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detachedCriteria.getExecutableCriteria(session); *~fZ9EkD
int totalCount = |^Z1 D TAw
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((Integer) criteria.setProjection(Projections.rowCount %L{ H_;z
j_\sdH*r
()).uniqueResult()).intValue(); kqSCKY1
criteria.setProjection {!xPq%
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(null); BG"~yyKA
List items = Tn/T:7C
iqghcY)
criteria.setFirstResult(startIndex).setMaxResults !'B.ad
dx[<@f2c
(pageSize).list(); (hd^
PaginationSupport ps = q~r)B}
\CB{Ut+s
new PaginationSupport(items, totalCount, pageSize, LS4c|Dv
oDx*}[/
startIndex); +GgWd=X.Y
return ps; ji`N1e,l
} g||{Qmr=1
}, true); `ItMn&P
} U}6'_ PRQ
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public List findAllByCriteria(final )dG7$,g
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DetachedCriteria detachedCriteria){ )m"NO/sJ2
return(List) getHibernateTemplate (zBa2Vmmv
._=Pa)T
().execute(new HibernateCallback(){ [Zl
publicObject doInHibernate ?
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(Session session)throws HibernateException { O:RPH{D
Criteria criteria = G[r_|-^S
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detachedCriteria.getExecutableCriteria(session); _+%-WFS|
return criteria.list(); xg'z_W
} ME1lQ7E4B
}, true); "4H&wHhT!
} e\ k=T}
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public int getCountByCriteria(final [L|H1ll
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DetachedCriteria detachedCriteria){ 4<70mUnt
Integer count = (Integer) [U]*OQH`e
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getHibernateTemplate().execute(new HibernateCallback(){ X7{ueP#L
publicObject doInHibernate Q4TI '/
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(Session session)throws HibernateException { AASw^A3p
Criteria criteria = z*YkD"]B
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detachedCriteria.getExecutableCriteria(session); NM/?jF@j*
return 5Qo\0YH
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criteria.setProjection(Projections.rowCount N/TUcG|m\
}qG{1Er
()).uniqueResult(); &'N{v@Oi)
} d%81}4f:
}, true); c7q1;X{:
return count.intValue(); %(Nu"3|$K=
} ._~_OVU
} (X,Ua+{
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用户在web层构造查询条件detachedCriteria,和可选的 *&+e2itmp
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 IBcCbNs!
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PaginationSupport的实例ps。 a:Y6yg%1>
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ps.getItems()得到已分页好的结果集 E08FUAth]#
ps.getIndexes()得到分页索引的数组 IwKhun
ps.getTotalCount()得到总结果数 k8F<j)"
ps.getStartIndex()当前分页索引 rC14X} X6
ps.getNextIndex()下一页索引 \$/)o1SG
ps.getPreviousIndex()上一页索引 x:88E78
7;#9\a:R?
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 %UI.E=`n
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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 *j?tcxq
;RflzY|D
一下代码重构了。 :`2<SF^0O
fB:9:NX
我把原本我的做法也提供出来供大家讨论吧: hq6fDRO/4
1Zx|SBF
首先,为了实现分页查询,我封装了一个Page类: HlqCL1\<
java代码: \-0@9E<D
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/*Created on 2005-4-14*/ wV+ W(
package org.flyware.util.page; D!h8NZ;El
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/** !lKO|Y
* @author Joa +J}
wYind
* $\Bzp<SN`
*/ =SB#rCH
publicclass Page { {^i7 3}@O
S 3Tp__
/** imply if the page has previous page */ 9 JBPE
privateboolean hasPrePage; .9
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53J!iNnXT6
/** imply if the page has next page */ WW{5[;LYiB
privateboolean hasNextPage; :.'<ndM
&M,a+|yuY
/** the number of every page */ cTCo~Pk4
privateint everyPage; MIo<sJuv
)XmV3.rI
/** the total page number */ {E-.W"t4
privateint totalPage; "X T7;!
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/** the number of current page */ :'91qA%Wr
privateint currentPage; D*6v.`]X
mcy\nAf5%
/** the begin index of the records by the current L3JFQc/oh~
Yz=(zj
query */ OXe+=Lp<
privateint beginIndex; QG*=N {%5
'A;G[(SYy
`uM:>
/** The default constructor */ &PaqqU.
public Page(){ dF:@BEo
QO0}-wZR
} ']Gqa$(YC
&)JQ6J_|\
/** construct the page by everyPage =.(yOUI
* @param everyPage >A5R
* */ %@#+Xpa+
public Page(int everyPage){ ^hzlR[
this.everyPage = everyPage; U`N|pPe:w
} AD#]PSB
V>ML-s9
/** The whole constructor */ L^bt-QbhO
public Page(boolean hasPrePage, boolean hasNextPage, 7K,Quq.%+
:K>v
F`SM
8]skAh
int everyPage, int totalPage, [bk2RaX:i
int currentPage, int beginIndex){ ^u&oS1U
this.hasPrePage = hasPrePage; oW(lQ'"
this.hasNextPage = hasNextPage; gyj.M`+y
this.everyPage = everyPage; zI$^yk-vn
this.totalPage = totalPage; &E0L7?l
this.currentPage = currentPage; 6E/>]3~!
this.beginIndex = beginIndex; wwrP7T+d
} dE19_KPm[j
"[2CV!_
/** 0D/u`-
* @return (|)`~z
* Returns the beginIndex. c[\ :^w^I6
*/ 4YDK`:4I~
publicint getBeginIndex(){ ~XN--4%Q
return beginIndex; >$SP2(Y~
} &[:MTK?x!
;Pf
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/** sd9$4k"
* @param beginIndex i!+D
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* The beginIndex to set. BLZ#vJR
*/ 6r!
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publicvoid setBeginIndex(int beginIndex){ 4
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this.beginIndex = beginIndex; Ls{z5*<FM
} b&[9m\AX`
aSdh5?
/** HeABU(o4
* @return !>fYD8Ft,
* Returns the currentPage. yTzP{I
*/ 5v <>%=
publicint getCurrentPage(){ ]x1MB|a6
return currentPage; W,"|([t4.\
} 9zSHn.y
CT,caa
/** DP\s-JpI[
* @param currentPage ?T=]?[
* The currentPage to set. !+T\}1f7d
*/ 0zm)MSg
publicvoid setCurrentPage(int currentPage){
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this.currentPage = currentPage; y6NOHPp@
} ie|I*;#
fHhm)T8KB
/** Atl`J.;G
* @return :W]?6=
* Returns the everyPage. aEU[k>&
*/ ]@X5'r"
publicint getEveryPage(){ z@;]Hy
return everyPage; W%LTcm
} 3D_Ky Z~M+
, dT.q
/** io:g]g
* @param everyPage QK _1!t3
* The everyPage to set. 88}+.-3t$
*/ 7'u<)V
publicvoid setEveryPage(int everyPage){ dv=y,q@W
this.everyPage = everyPage; %pj6[x`@
} PN9^ sLx=
u.;zz'|
/** ^kZfE"iE2
* @return "<o[X ?u
* Returns the hasNextPage. =|>CB
*/ wKF #8Y
publicboolean getHasNextPage(){ -
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return hasNextPage; piYv}4;:(
} OQzJRu)mF#
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/** <!b~7sZkTc
* @param hasNextPage RtVy^~=G
* The hasNextPage to set. UjibQl3:m
*/ 5`qt82Qm
publicvoid setHasNextPage(boolean hasNextPage){ gXr"],OM;
this.hasNextPage = hasNextPage; A4LGF
} GT\,
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/** i`[5%6\"&
* @return [MSLVTR
* Returns the hasPrePage. EvZ;i^.8LS
*/ n]M1'yU
publicboolean getHasPrePage(){ \b{Aj,6,
return hasPrePage; u I$|M
} / hUuQDJ
5G .Fi21
b
/** Bz}Dgbb
* @param hasPrePage fw>@:m_bK
* The hasPrePage to set. !iKR~&UpAL
*/ u] C/RDTH
publicvoid setHasPrePage(boolean hasPrePage){ TymE(,1
this.hasPrePage = hasPrePage; hUirvDvX
} q6A!xQs<
zJ{?'kp
/** 6o@}k9AN
* @return Returns the totalPage. 89@\AjI
* 8N<0|u
*/ W{E22J}
publicint getTotalPage(){ o(xRq;i
return totalPage; #_yQv? J
} rfqw/o
xdWfrm$;ZA
/** (Wkli:Lq
* @param totalPage 2
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* The totalPage to set. Y"
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*/ rkhQoYZ[
publicvoid setTotalPage(int totalPage){ dz/'
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this.totalPage = totalPage; @|Z:7n6S
} :xw2\:5~0
Ov3W;jD
} 9k\`3SE
Z09FW>"u
K/RQ-xd4
H5t 9Mg|
(H *-b4]/
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 b i^h&H
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个PageUtil,负责对Page对象进行构造: 1xK'1g72
java代码: $>E\3npV
"bZV<;y6
\8\)5#?
/*Created on 2005-4-14*/ f.V;Hl,
package org.flyware.util.page; Oq"(oNG@
j0J}d _
import org.apache.commons.logging.Log; ~82[pY
import org.apache.commons.logging.LogFactory; o?\)!_Z|
Ore$yI}!m
/** UnNvlkjq9
* @author Joa )#-27Y
* 4GJ1P2
*/ 'B}pIx6k~
publicclass PageUtil { f@l 6]z{.L
~ZU;0#
privatestaticfinal Log logger = LogFactory.getLog C("PCD
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(PageUtil.class); "^-U#f>k
M9Gs^
/** .4={K)kz|F
* Use the origin page to create a new page *D`qcv
* @param page 'G6TSl
* @param totalRecords [+$l/dag
* @return Z :f0>
*/ Z&8
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publicstatic Page createPage(Page page, int GF~^-5
GypZ!)1
totalRecords){ 8xhXS1
return createPage(page.getEveryPage(), GZT}aMMSJ
}C>Q
page.getCurrentPage(), totalRecords); i}
96,{
} /H.QGPr
PK1j$&F
/** hT6:7_UD
* the basic page utils not including exception *ggTTHy
>(z{1'f{
handler
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* @param everyPage |Y3!Lix
* @param currentPage hZnT`!iFE^
* @param totalRecords -Nmf}`_
* @return page KsYT3
*/ A/N*Nc
publicstatic Page createPage(int everyPage, int zO{$kT\r&
)6)|PzMQ'
currentPage, int totalRecords){ j)\g0u6
everyPage = getEveryPage(everyPage); Fk D
currentPage = getCurrentPage(currentPage); mOwgk7s[J
int beginIndex = getBeginIndex(everyPage, >7!aZO
_dqjRhu
currentPage); _5a]pc$\Y]
int totalPage = getTotalPage(everyPage, YVVX7hB
7ka^y k@Q
totalRecords); OXDlwbwL
boolean hasNextPage = hasNextPage(currentPage, ))c;DJc
lp[3z&u
totalPage); ub6\m=Y7
boolean hasPrePage = hasPrePage(currentPage); ($(6]?J(?7
~J2-B2S!
returnnew Page(hasPrePage, hasNextPage, 322W"qduTZ
everyPage, totalPage, Qv8#{y@U
currentPage, T\c;Ra
?>MD /l(l
beginIndex); DHpU?;|3
} m6V1m0M
]SrKe-*:U
privatestaticint getEveryPage(int everyPage){ [e)81yZG>
return everyPage == 0 ? 10 : everyPage; :w_F<2d0
0
} !boKrSw
9CJUOB>]
privatestaticint getCurrentPage(int currentPage){ Af=%5%
return currentPage == 0 ? 1 : currentPage; 0!=e1_
} 3sGrX"0D
f[7'kv5S
privatestaticint getBeginIndex(int everyPage, int t^?8Di\
E E?v~6"&
currentPage){ A`(p6 H"s
return(currentPage - 1) * everyPage; V$
38
} *wt yyP@
qh$D;t1=
privatestaticint getTotalPage(int everyPage, int 7qE V5!
qNHS 1
totalRecords){ w GZ(bKyO
int totalPage = 0; =\4w" /Y
7 g ]]>
if(totalRecords % everyPage == 0) )I]E%ut{4,
totalPage = totalRecords / everyPage; Tp`)cdcC[
else >|0yH9af
totalPage = totalRecords / everyPage + 1 ; ?f']*pD8
B0p>' O2
return totalPage; SUD]Wl7G`r
} =)M 8>>l
-Kg@Sj/U}R
privatestaticboolean hasPrePage(int currentPage){ UShn)3F
return currentPage == 1 ? false : true; U]vNcQj
} (/YC\x?
mk\U wv
privatestaticboolean hasNextPage(int currentPage, i?=3RdP/R1
]p'Qk
int totalPage){ 3\=8tg p
return currentPage == totalPage || totalPage == HKOJkbVZ2^
u
MzefRN
0 ? false : true; ^'EEry
} C,2IET
j,/o0k,
W\.f:"2qr
} /<:9NP'^
;x^&@G8W`
EoU}@MjM~
L*FmJ{Yf
gY0*u+LF
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。 bG^eP:r
Jr17pu(t
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 4n3QW%#
2IjqTL
做法如下: hN\E8"To
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 w41#?VC/
hph 3kfR
的信息,和一个结果集List: O.rk!&N
java代码: )Xd=EWGUS
GsDSJz
QQ2xNNF[
/*Created on 2005-6-13*/ [&NF0c[i
package com.adt.bo; R$6Y\ *L[
}QJE9;<e
import java.util.List; Slv}6at5
~fCD#D2KU
import org.flyware.util.page.Page; -HoPECe
J=zZGd%
/** GQF7]j/
* @author Joa (59<Zo
*/ yv3myaS
publicclass Result { |lJXI:GG
/2l4'Q=
private Page page; r}hj,Sq'
7%7_i%6wP
private List content; tm]75*?
fiw~"2U
/** B|extWwu
* The default constructor Tr@`ozp8
*/ ?5B}ZMW
public Result(){ AO']Kmm
super(); 5 yA^ n6
} #{h4lte
|{9"n<JW
/** Y!POUMA
}A
* The constructor using fields 1M3U)U
* SF.,sCk
* @param page a S<JsB
* @param content 6 Dg[b
*/ $oxPmELtpe
public Result(Page page, List content){ W;KHLHp-
this.page = page; + !_^MB kk
this.content = content; ;U20g:K
} |;D[Al5AMc
55$by.rf?
/** ).ugMuk
* @return Returns the content. PFPfLxna
*/ 1Eg}qU,:
publicList getContent(){ ~Zj?%4
return content; h+Q==
} k.lnG5e
mD )Nh
/** 8<]> q
* @return Returns the page. a?JU(
*/ /u #9M {
public Page getPage(){ B1LnuB%
return page; 8|d[45*q
} 4yBe(&N-d
#e9B|Y?b
/** bM-Y4[
* @param content }*R"yp
* The content to set. :m37Fpz&b
*/ 8tdUnh%/
public void setContent(List content){ "%.#/!RG
this.content = content; 3}h&/KN{
} ;^rZ"2U
l
CiMy_`H
/** 3i s.c)
* @param page cA/2,i
* The page to set. dUe"qH29s
*/ {Ua5bSbh
publicvoid setPage(Page page){ {X"X.`p
this.page = page; jM7}LV1Ck
} +u)'
} l|&|+u#
o_5|L9
0\h2&
Ft>ixn
R#T6Ii
2. 编写业务逻辑接口,并实现它(UserManager, RuXK` ySv
CLYcg$V
UserManagerImpl) nEGku]pCH{
java代码: -Z;:_"&9
Jhj]rsGk
H/L3w|2+
/*Created on 2005-7-15*/ Z2$-},i
package com.adt.service; +pFz&)?
#);
6+v
import net.sf.hibernate.HibernateException; ZDVaKDqZ_
.4^Paxz
import org.flyware.util.page.Page; 3[e@mcO
1:&$0jU&U
import com.adt.bo.Result; u5,IH2BU
=Wjm_Rvk9
/** GB
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* @author Joa lhjPS!A~
*/ d@w
I:
7
publicinterface UserManager { Yb6\+}th
6C3y+@9
public Result listUser(Page page)throws #|e<l1 F
F;_;lRAb
HibernateException; #15q`w
[wu%t8O2
} %2L9kw'
}BfwMq4E)n
aSK$#Xeu
##n\9ipD
P,%|(qB
java代码: .9ROa#7U;n
S3=J1R,
,2cw9?<
/*Created on 2005-7-15*/ bZlAK)
package com.adt.service.impl; 1U9iNki
*FAg^G&1
import java.util.List; N&ddO-r[s
WI6er;D
import net.sf.hibernate.HibernateException; K{iayg!k
*1%g=vb
import org.flyware.util.page.Page; pTN_6=Y"
import org.flyware.util.page.PageUtil; zCQv:.0L
?3|ZS8y
import com.adt.bo.Result; eU12*(
import com.adt.dao.UserDAO; )l"0:1I g
import com.adt.exception.ObjectNotFoundException; S4(IYnwN
import com.adt.service.UserManager; S_QDYnF)`
t^[{8,N
/** L{Th>]X
* @author Joa 4Cfwz-Qo
*/ /;lk.-yU
publicclass UserManagerImpl implements UserManager { l9jcoVo.
tT
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private UserDAO userDAO; E?zp?t:a
+|0 m6)J]
/** 49#-\=<gt
* @param userDAO The userDAO to set. ~q4y'dBy*
*/ [6Wr
t8"
publicvoid setUserDAO(UserDAO userDAO){ EtL=_D-
this.userDAO = userDAO; 'Oc8[8
} @2u<Bh}}
J)-owu;
/* (non-Javadoc) 7]^Cg;EtM:
* @see com.adt.service.UserManager#listUser *\`C!r
jsG9{/Ov3
(org.flyware.util.page.Page)
[:k'VXL
*/ 4R0_%x6vG
public Result listUser(Page page)throws t"L:3<U7
\Dc\H)
HibernateException, ObjectNotFoundException { v_ J.M ]
int totalRecords = userDAO.getUserCount(); tb
i;X=5
if(totalRecords == 0) /qCYNwWH9
throw new ObjectNotFoundException P o_9M4kU
4H,DG`[Mo
("userNotExist"); z_H2L"Z
page = PageUtil.createPage(page, totalRecords); 2Fh_
List users = userDAO.getUserByPage(page); &p%,+|
returnnew Result(page, users); 5bAXa2Vt
} WDX?|q9rCt
;e{2?}#8&
} kj8zWG4KH
`SG70/
5FzRusNiA
L=p.@VSZ
+-Dd*yD6<
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 \xdt|:8
3xe8DD
询,接下来编写UserDAO的代码: 0g+@WK6y
3. UserDAO 和 UserDAOImpl: UtutdkaS
java代码: dnx}c4P
GGBe/X
a~%ej.)l
/*Created on 2005-7-15*/ _c&*'IY[V
package com.adt.dao; 4EpzCaEZ
Za} |Ee
import java.util.List; m^=,
RfUUd
f4_\F/
import org.flyware.util.page.Page; izKk@{Md
pFK
|4u
import net.sf.hibernate.HibernateException; (kHR$8GFM
j@ "`!uPz
/** bXW)n<y
* @author Joa l=oVC6C
*/ ELPJ}moWZ
publicinterface UserDAO extends BaseDAO { Y1~SGg7(@
?
vlGr5#
publicList getUserByName(String name)throws 9t[278B6
WNx^Rg"
>'
HibernateException; ZChY:I$<
e!8_3BE
publicint getUserCount()throws HibernateException; WY,t> 1c
@v'D9 ?
publicList getUserByPage(Page page)throws I>xB.$A
4"2/"D0
HibernateException; c,qCZ-.Sg
)k1,oUx
} \XN5))
@b/2'
KH7]`CU
KCFwO'
mx[^LaR>v
java代码: o`U\Nhq
VB#31T#q?
g5Vr2
/*Created on 2005-7-15*/ 2%8Y-o?
package com.adt.dao.impl; 3oKGeB;Ja
[0LqZ<\5
import java.util.List; %(Ys-GeGr
""+*Gn7^8
import org.flyware.util.page.Page; pd1m/:
Psa8OJan
import net.sf.hibernate.HibernateException; kziBHis!
import net.sf.hibernate.Query; a(~YrA%~
u
s0'7|{q
import com.adt.dao.UserDAO; =tNiIU
Tc(R-Wi
/** {XX Nl)%
* @author Joa C]H <L#)ZU
*/ v6VhXV6$|
public class UserDAOImpl extends BaseDAOHibernateImpl i6CYD
Ak1)
implements UserDAO {
]mj+*l5
55DzBV
/* (non-Javadoc) Vr1|%*0Tv
* @see com.adt.dao.UserDAO#getUserByName >l1Yhxd_0*
IpJ v\zH7
(java.lang.String) O)|4>J*B
*/ Ltw7b
publicList getUserByName(String name)throws <`3(i\-X
EAB+kY
HibernateException { K)+l 6Q
String querySentence = "FROM user in class ?GarD3#A
D.o|($S0
com.adt.po.User WHERE user.name=:name"; 3R*@m
Query query = getSession().createQuery X-,y[ )
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(querySentence); cv4M[]U~
query.setParameter("name", name); 2S6EDXc
return query.list(); =.oWg uzu
} ws?s
I0vnd7
/* (non-Javadoc) D,j5k3< #
* @see com.adt.dao.UserDAO#getUserCount() m#$za7
*/ }?J5!X
publicint getUserCount()throws HibernateException { RM1uYFs<
int count = 0; CD1=2
String querySentence = "SELECT count(*) FROM _0["J:s9
/A.i5=k
user in class com.adt.po.User"; /&:9VMMj
Query query = getSession().createQuery .K1E1Z_
l&Ghs@>Kl
(querySentence); dO;vcgvb
count = ((Integer)query.iterate().next xg^^ @o
@%nUfG7TQ
()).intValue(); xJLO\B+gM
return count; TY\"@(Q|G
} <57l|}8
/VO@>Hoh
/* (non-Javadoc) _0q~s@-
* @see com.adt.dao.UserDAO#getUserByPage 8{fz0H.<?
FqxOHovE
(org.flyware.util.page.Page) 1GE%5
*/ nj0AO0
publicList getUserByPage(Page page)throws k3[h'.ps
6xIYg ^
HibernateException { T;r];Y(b*
String querySentence = "FROM user in class (OcNC/9
)v{41sM+
com.adt.po.User"; -xu.=n@,
Query query = getSession().createQuery R(83E
B~_
nvK7*-
(querySentence); <`_OpNxqW
query.setFirstResult(page.getBeginIndex()) niEEm`"
.setMaxResults(page.getEveryPage()); :@`(}5F4
return query.list(); s]vJUC,s
} <o7#?AcPu
*\:_o5o%[T
} eQVPxt2N
d3G{0PX
"E|r 3cN
Ru^ ONw"
I/V )z9
至此,一个完整的分页程序完成。前台的只需要调用 zO5u{
$%%>n^??
userManager.listUser(page)即可得到一个Page对象和结果集对象 hAr[atu87
!8@rK$DB
的综合体,而传入的参数page对象则可以由前台传入,如果用 E}' d,v#Z{
n~ >h4=h
webwork,甚至可以直接在配置文件中指定。 +F~0\#d
&<V_[Wh"
下面给出一个webwork调用示例: ;#yu"6{
java代码: QS [B
"gvw0)
h @,e`Z
/*Created on 2005-6-17*/ IO!1|JMr6
package com.adt.action.user; )=E~CpKV
a5}44/%
import java.util.List; 9^QYuf3O
wz*A<iU
import org.apache.commons.logging.Log; #}!>iFBcH
import org.apache.commons.logging.LogFactory; r d6F"W
import org.flyware.util.page.Page; Ls>u`hG
8yWu{'G
import com.adt.bo.Result; 5\ w=(c9A
import com.adt.service.UserService; .p(6' TYnI
import com.opensymphony.xwork.Action; Q_kT}6#(J=
Z0ncN])
/** QI#*5zm
* @author Joa 'y6!%k*
*/ , |.*,
publicclass ListUser implementsAction{ ~njbLUB
qHR^0&
privatestaticfinal Log logger = LogFactory.getLog Cl9SPz
RZ|HwYG
(ListUser.class); g{v5mly
`
-[Bo
private UserService userService; C^,4`OI
&V#z kW
private Page page; 6A$_&?
gR;8ht(pd(
privateList users; uspkn1-
;c X^8;F0
/* c8-69hb?
* (non-Javadoc) s("Cn/ZkS
* gVa+.x]
* @see com.opensymphony.xwork.Action#execute() 3|K=%jr[
*/ Q"_T2fl]vP
publicString execute()throwsException{ QtnM(m
Result result = userService.listUser(page); $m:2&lU3
page = result.getPage(); &Mhv XHI
users = result.getContent(); [+%d3+27
return SUCCESS; {1Ju}=69
} 1 ;\]D9i
']ITuP8
/** KUp
* @return Returns the page. T/GgF&i3
*/ \)^,PA3
public Page getPage(){ 0q[p{_t`
return page; N)y^</Ya
} 29a_ZU7e6
hJw
|@V
/** .DDg%z
* @return Returns the users. T_@[k
*/ p.rdSv(8'
publicList getUsers(){ mUrS&&fu8
return users; ?w]"~
} A6^p}_
E!zd(
/** %\}dbYS
'
* @param page |rE!
* The page to set. n|70x5Z?}J
*/ $` Z>Lm*
publicvoid setPage(Page page){ S'Z70 zJ
this.page = page; dGbU{#"3s
} =vqsd4
KInUe(g<9M
/** +cz"`T`X 2
* @param users .cg=
* The users to set. r5MxjuOB1
*/ E-UB -"6
publicvoid setUsers(List users){ xm<v"><
this.users = users; zwM"`z
} T}n N=Q4
^>N8*=y
/** 4Qa@`
* @param userService Ur'9bl{5
* The userService to set. pN\)(:"8v
*/ >_;kT y,
publicvoid setUserService(UserService userService){ RLdlz
this.userService = userService; )KSisEL
} :/o C:z\h
} { 1+Cw?1d
A",eS6
]b4pI*:$I
; cGv] A+
U9 1 &|
上面的代码似乎看不出什么地方设置了page的相关初值,事实上, k2EHco0BG
K :1g"
可以通过配置文件来进行配置,例如,我想每页显示10条记录,那 oM6j>&$b
^cYStMjpy
么只需要: 't
+"k8
java代码: r_b8,I6{]
v6wRME;JA
JB&G~7Q85
<?xml version="1.0"?> y,MPGW_
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork <RhOjZgyZ
F(#ha J$>
1.0//EN" "http://www.opensymphony.com/xwork/xwork- EkN_8(w
OENzG~
1.0.dtd"> Y\.-v\uJu
r?fH
&u
<xwork> h/,R{A2mO
u@<Pu@?xm
<package name="user" extends="webwork- %lN2n,AK
!\QeBd+
interceptors">
%b=Y
<v
3(1]FKZtt
<!-- The default interceptor stack name b6 $,Xh
8]S,u:E:N
--> 7=}6H3|&
<default-interceptor-ref + c`AE
/+>)"D6'
name="myDefaultWebStack"/> \I?w)CE@R
>xT^RYS
<action name="listUser" r]v&t
"[k1D_PZ
class="com.adt.action.user.ListUser"> m;dm|4L^
<param .:rmA8U[
Rv98\VD"
name="page.everyPage">10</param> }i(qt&U;
<result IE2CRBfs
~e{H#*f&1/
name="success">/user/user_list.jsp</result> )CJES!!
W
</action> 1@xP(XS
"u_i[[y
</package> <0#^7Z
n=q=zn;
</xwork> o7.e'1@
%dc3z"u
N#4N?BBP"
X/l;s
cph~4wCS[U
@dl8(ILk'
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 w!\3ICB
vYdR ht\(
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。 jo}1u_OJ
@D)Z{=>{=5
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 [& ^RP,N~
g5i#YW
P^pFqUL7#
1]T|6N?
9t?L\
我写的一个用于分页的类,用了泛型了,hoho Vo\H<_=G
1_uvoFLk
java代码: tmO`|tn&
+TH3&H5I_A
6g"C#&{@
package com.intokr.util; >"%ob,c:#
{pWBwf>R C
import java.util.List; xST4}Mb^f
:=*}htP4C
/** " !-Kd'V
* 用于分页的类<br> |f\D>Y%)
* 可以用于传递查询的结果也可以用于传送查询的参数<br> eZH~je{1
* x0A7O
* @version 0.01 /_)l|<k+V
* @author cheng IxOc':/jY
*/ )1lu=gc
public class Paginator<E> { $
KB
privateint count = 0; // 总记录数 )T1iN(Z
privateint p = 1; // 页编号 }^Gd4[(,g
privateint num = 20; // 每页的记录数 :_xh(W+2<
privateList<E> results = null; // 结果 &$=! dA
*/(I[p
/** l1A5Y5x9=
* 结果总数 <r~wZ}s
*/ [} -3PpF
publicint getCount(){ T p<s1'"
return count; wC`;f5->
} w_Uh
_fn1)
publicvoid setCount(int count){ @pFj9[N
this.count = count; 71"+<C .
} :U'Cor
H
e)@3m.
/** j+kC-U;
* 本结果所在的页码,从1开始 8md*wEjk
* &^!h}D%T/
* @return Returns the pageNo. 8AL\ST51x"
*/ l+'F_a
publicint getP(){ aC!EWgwW[
return p; .WX,Nd3@
} ^:KO_{3E
ab.tH$:<
/** c?E{fD"Fc3
* if(p<=0) p=1 rjk ( X|R*
* 0fArF*
* @param p oehaQ#e
*/ 1/;o
publicvoid setP(int p){ (dqCa[
if(p <= 0) =-#G8L%Q
p = 1; MsOs{2
)2
this.p = p; w5,Mb
} [syj#
3^,QIG
/** iPj~I
* 每页记录数量 ^YlI>_3s
*/ TQ]dW
publicint getNum(){ Z9K})47T
return num; gb" 4B%Hm
} DHw<%Z-J
W0I4Vvh_"
/** 8)j@aiF`
* if(num<1) num=1 eE(b4RCM
*/ skg|>R,kE
publicvoid setNum(int num){ n V&cC
if(num < 1) Bp?
num = 1; &7>zURv
this.num = num; 56}X/u
} h8{(KRa 6
B&0;4
/** =&nW~<- v
* 获得总页数 ,Nm$i"Lg
*/ ZDt?j
publicint getPageNum(){ k N7Bd}
return(count - 1) / num + 1; -ijC_`>
} 6'vbT~S!
.;
Q:p*
/** `A@w7J'
* 获得本页的开始编号,为 (p-1)*num+1 l'[A?%L%{
*/ !&^gaUa{
publicint getStart(){ 8LzBh_J?
return(p - 1) * num + 1; u<xo/=Z
} =r2]uW9
I/6)3su%
/** N2C7[z+l`
* @return Returns the results. hz:pbes
*/ M@et6aud;K
publicList<E> getResults(){ L%"LlSg
return results; C[sh,
} 6gL-OJNo
T{v>-xBRy
public void setResults(List<E> results){ w_tJ7pz8T
this.results = results; (Z]HX@"{J
} }H> ^o9
>l']H*&B<
public String toString(){ 4T6 {Y
StringBuilder buff = new StringBuilder IxZb$h[
V)ig)(CT
(); Yf@e=:
buff.append("{"); L{-LX=G^
buff.append("count:").append(count); =c.5874A`
buff.append(",p:").append(p); fWnD\mx?0
buff.append(",nump:").append(num); ]6r;}1c
buff.append(",results:").append zi9[)YqxPH
g4p
(results); ]}|byo
buff.append("}"); SRIA*M.B}
return buff.toString(); ypOLp SYk
} kYzKU2T\W
>Gml4vGK
} %QmxA
7fW
Zdc63fllM
Mj#-j/{x{5