Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 #l!nBY ~
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 aqv'c
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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 )h0b}HMW)
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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 /])P{"v$^
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。 ]$I}r=
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分页支持类: L.: 8qY
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java代码: 0x fF
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package com.javaeye.common.util; XfN(7d0
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import java.util.List; jW>K#vj
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publicclass PaginationSupport { k`J|]99Wb
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publicfinalstaticint PAGESIZE = 30; ~nApRC)0
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privateint pageSize = PAGESIZE; zpZfsn!
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privateList items; aP#/%
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privateint totalCount; J M`[|"R%
q}W})
privateint[] indexes = newint[0]; =Q*3\)7
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privateint startIndex = 0; s;-AZr)
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public PaginationSupport(List items, int &0xM 2J
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totalCount){ cZ# %tT#
setPageSize(PAGESIZE); l z-I[*bA
setTotalCount(totalCount); AWJA?
setItems(items); ]J@-,FFC
setStartIndex(0); tS-gaT`T
} !s:e
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public PaginationSupport(List items, int ?:G 3U\M
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totalCount, int startIndex){ r-.>3J
setPageSize(PAGESIZE); /aIGq/;Y+a
setTotalCount(totalCount); &xUD(
setItems(items); \`E^>6!]q
setStartIndex(startIndex); J_?v=dW`
} _,/~P)
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public PaginationSupport(List items, int 8:>V'j
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totalCount, int pageSize, int startIndex){ l qKj;'
setPageSize(pageSize); Qj*.Z4ue
setTotalCount(totalCount); Dp!91NgB p
setItems(items); MpBdke$
setStartIndex(startIndex); x0WinLQ
} ZvMU3])u
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publicList getItems(){ LD1&8kJ*l
return items; )Yv=:+f
} ? ^W1WEBm
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publicvoid setItems(List items){ ex6R=97uA
this.items = items; _{-[1-lN5_
} gKQV99
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publicint getPageSize(){ i[IFD]Xy!j
return pageSize; ou <3}g
} EXCE^Vw
N*}soMPV^.
publicvoid setPageSize(int pageSize){ = IRot
this.pageSize = pageSize; _d5:Y
} V;xPZ2C;
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publicint getTotalCount(){ e^>>"tr
return totalCount; =wdh#{
} EGUlLqP6e
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publicvoid setTotalCount(int totalCount){ BX0lk
if(totalCount > 0){ $qQYxx@
this.totalCount = totalCount; {x_.QWe5
int count = totalCount / UpG DLb f^
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pageSize; @/.#
/
if(totalCount % pageSize > 0) ZyUcL_
count++; MONX&$
indexes = newint[count]; i"0Bc{cQ
for(int i = 0; i < count; i++){ MF4(
indexes = pageSize * Xkhd"Axi
+M0pmK!
i;
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} kWXLncE
}else{ 5
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this.totalCount = 0; 4f[%Bb
} ~V8z%s@
} Q6qW?*Y
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publicint[] getIndexes(){ H`CID*Ji
return indexes; \0b}Z#'0
} VV$t*9w
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publicvoid setIndexes(int[] indexes){ )@N d3Z
this.indexes = indexes; FOXSs8"c]!
} B}iEhWO6
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publicint getStartIndex(){ 'k,2*.A
return startIndex; f jx`|MJ
} I%3[aBz4
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publicvoid setStartIndex(int startIndex){ m-Eh0Zl>Z
if(totalCount <= 0) JXB)'d0
this.startIndex = 0; WoEK #,I;
elseif(startIndex >= totalCount) [SPx
this.startIndex = indexes MET9rT
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[indexes.length - 1]; ^e.-Ji
elseif(startIndex < 0) :o'x?]
this.startIndex = 0; R=z])
else{ yix[zfQt0
this.startIndex = indexes =>$)F 4LW
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[startIndex / pageSize]; ;+9OzF ;
} IO\4dU)
} gQn%RPMh
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publicint getNextIndex(){ Y sM*d
int nextIndex = getStartIndex() + }Pcm'o_wT
#a8kA"X
pageSize; bKQho31a'
if(nextIndex >= totalCount) QUrPV[JQ
return getStartIndex(); &$MC!iMh
else >P/36'
return nextIndex; JVc{vSa!rm
} Xh9QfT ,
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publicint getPreviousIndex(){ 4zoQe>v~
int previousIndex = getStartIndex() - l(t&<O(m9
(> al-vZ6A
pageSize; 7UfNz60+~
if(previousIndex < 0) <tr]bCu}
return0; l=~!'1@L}
else GJ ^c^`
return previousIndex; SMN.AJ
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} @>2pY_
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} SVCh!/qe\
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抽象业务类 "=h1gql'
java代码: fkV@3sj
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/** {r^_ g(.q
* Created on 2005-7-12 *6Wiq5M>.
*/ B8@mL-Z-;
package com.javaeye.common.business; ^? fOccfQ{
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import java.io.Serializable; Rlq7.2cP
import java.util.List; :#rP$LSYC
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import org.hibernate.Criteria; xTHD_?d
import org.hibernate.HibernateException; .t8)`MU6.
import org.hibernate.Session; \v2!5z8|
import org.hibernate.criterion.DetachedCriteria; Y
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import org.hibernate.criterion.Projections; &G{GLP?H
import &jqaW2
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org.springframework.orm.hibernate3.HibernateCallback; ,Z`}!%?
import +3v)@18B1
^m\o(R
org.springframework.orm.hibernate3.support.HibernateDaoS RT[p!xL
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upport; {U5sRM|I
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import com.javaeye.common.util.PaginationSupport; :qzg?\(
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public abstract class AbstractManager extends Oa[
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HibernateDaoSupport { QPlU+5Cx
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privateboolean cacheQueries = false; \:vF FK4a
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privateString queryCacheRegion; }Fe~XO`
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publicvoid setCacheQueries(boolean r%,?uim#
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cacheQueries){ }M07-qIX{
this.cacheQueries = cacheQueries; #xIg(nG
} >M<3!?fW)
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publicvoid setQueryCacheRegion(String TvU
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queryCacheRegion){ w-|Rb~XT
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this.queryCacheRegion = iOfm:DTPr
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queryCacheRegion; -#\ T
} l+ }=D@l
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publicvoid save(finalObject entity){ 7oZ:/6_>
getHibernateTemplate().save(entity); osp~)icun
} 7[ ovEE54
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publicvoid persist(finalObject entity){ Wt.DL mO
getHibernateTemplate().save(entity); *>m[ZJd %=
} WK%cbFq(
} z'Jsy[s
publicvoid update(finalObject entity){ +Mj6.X
getHibernateTemplate().update(entity); 2?,Jn&i5
} >8Oa(9 n
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publicvoid delete(finalObject entity){ )5|9EXh
getHibernateTemplate().delete(entity); \/Y(m4<P
} Ib(C`4%
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publicObject load(finalClass entity, x^s,<G
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finalSerializable id){ sI,cX#h&Y
return getHibernateTemplate().load !LKxZ"
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(entity, id); OVLVsNg
} m?S;sew@5
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publicObject get(finalClass entity, k_pv6YrE
{B+}LL!
finalSerializable id){ 2ZK]}&yC
return getHibernateTemplate().get 7Kw'Y8
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(entity, id); juEPUsE
} ~RR!~q
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publicList findAll(finalClass entity){ >a8iY|QY
return getHibernateTemplate().find("from 0)&!$@HW
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" + entity.getName()); Nj9A-*0g6N
} 0U=wGIO
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publicList findByNamedQuery(finalString EL,k z8
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namedQuery){ KVZB`c$<t
return getHibernateTemplate 9evr!=":
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().findByNamedQuery(namedQuery); rbvk.:"^w
} 5FZw
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publicList findByNamedQuery(finalString query, rXB;#ypO
}nrjA0WN
finalObject parameter){ ny-:%A
return getHibernateTemplate >)M{^
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().findByNamedQuery(query, parameter); ,YD7p= PY
} Xs2}n^#i
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publicList findByNamedQuery(finalString query, U[wx){[|
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finalObject[] parameters){ &%OY"Y~bI!
return getHibernateTemplate .UPh
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().findByNamedQuery(query, parameters); D:T]$<=9
} D4VDWv
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publicList find(finalString query){ a=2.Y?
return getHibernateTemplate().find Y4k2=w:D
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(query); >.meecE?Q
} n&[CTOV
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publicList find(finalString query, finalObject -8l<5g7
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parameter){ "\wMs
return getHibernateTemplate().find [
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(query, parameter); rUI?{CV
} >~o-6g
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public PaginationSupport findPageByCriteria wv9HiHz8gD
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(final DetachedCriteria detachedCriteria){ "# *W#ohVA
return findPageByCriteria UF+Qx/4h0
&5 "!0
(detachedCriteria, PaginationSupport.PAGESIZE, 0); G4(R/<J,BQ
} @j\:K<sk
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public PaginationSupport findPageByCriteria 03~ ADj
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(final DetachedCriteria detachedCriteria, finalint WE\TUENac(
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startIndex){ 4aHogheg
return findPageByCriteria s!IIvF
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(detachedCriteria, PaginationSupport.PAGESIZE, L$5,RUy
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startIndex); DP{nvsF
} +[G9PP6
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public PaginationSupport findPageByCriteria 2 5 \S>
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(final DetachedCriteria detachedCriteria, finalint \OW:-
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pageSize, d6MWgg
finalint startIndex){ Qj^Uz+b
return(PaginationSupport) cKVFykwM
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getHibernateTemplate().execute(new HibernateCallback(){ p]kEH\
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publicObject doInHibernate c,@Vz
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(Session session)throws HibernateException { 6 - 3?&+
Criteria criteria = iM!2m$'s
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detachedCriteria.getExecutableCriteria(session); nI3p`N8j*
int totalCount = v6 5C
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((Integer) criteria.setProjection(Projections.rowCount `Wx|
4
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()).uniqueResult()).intValue(); "lt <$.
criteria.setProjection D W U=qD+
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(null); obvE m[x!Z
List items = :of([e|u6
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criteria.setFirstResult(startIndex).setMaxResults ! t!4CY
f9#zV2ke]
(pageSize).list(); Y*BmBRN
PaginationSupport ps = Qhj']>#g
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new PaginationSupport(items, totalCount, pageSize, U$5x#{AFp
S]@;`_?m{
startIndex); ;87PP7~
return ps; :|(YlNUv
} Bv7FZK3
}, true); WD%(RC"Q
} ku,{NY
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public List findAllByCriteria(final brTNwRze
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DetachedCriteria detachedCriteria){ - ;gQy[U
return(List) getHibernateTemplate hj1;f<'
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().execute(new HibernateCallback(){ Il&FC
publicObject doInHibernate 6
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(Session session)throws HibernateException { VKPEoy8H
Criteria criteria = C
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detachedCriteria.getExecutableCriteria(session); 'TYO-'aC
return criteria.list(); -G>J
} U LS>v
}, true); "81'{\(I_
} Ar\fA)UQ`
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public int getCountByCriteria(final ~ox}e(xy
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DetachedCriteria detachedCriteria){ WT\wV\Pu
Integer count = (Integer) kL zjK]4 *
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getHibernateTemplate().execute(new HibernateCallback(){ O`CZwXD
publicObject doInHibernate _b8KK4UR
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(Session session)throws HibernateException { g5#LoGc
Criteria criteria = T%.Yso{
@MibKj>o
detachedCriteria.getExecutableCriteria(session); eTjPztdJbx
return @"s<0T^H
oC"
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criteria.setProjection(Projections.rowCount 9+y&&;p
8/p ]'BLf
()).uniqueResult(); =xkaF)AW&v
} jy0aKSn8
}, true); Otu?J_ d3
return count.intValue(); 9Avj\G
} $`UdG0~
} RCfeIHL
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用户在web层构造查询条件detachedCriteria,和可选的 ?`OFn F,K
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 W`LG.`JW
{
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PaginationSupport的实例ps。 Vxrj(knck,
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ps.getItems()得到已分页好的结果集 ?$)a[UnqX
ps.getIndexes()得到分页索引的数组 5fs,UH
ps.getTotalCount()得到总结果数 VO1
ps.getStartIndex()当前分页索引 `[E-V
ps.getNextIndex()下一页索引 (eb65F@ P
ps.getPreviousIndex()上一页索引 Ax|'uvVAPT
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 x]Nx,tt
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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 gs0jwI
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一下代码重构了。 %q r,Ssa/
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我把原本我的做法也提供出来供大家讨论吧: V@RdvQy
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首先,为了实现分页查询,我封装了一个Page类: 0 GFho$f
java代码: ?$I9/r
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6 ym$8^
/*Created on 2005-4-14*/ f"\klfrRI_
package org.flyware.util.page; m0W3pf
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/** :SwA) (1
* @author Joa }#~E-N3x
* GXLh(d!C
*/ +F,])p4,]i
publicclass Page { g>7i2
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/** imply if the page has previous page */ 1W.oRD&8j/
privateboolean hasPrePage; n}9<7e~/
K)1Lg?j
/** imply if the page has next page */ F;/^5T3wI
privateboolean hasNextPage; q b=%W
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/** the number of every page */ T.QJ#vKO0
privateint everyPage; 9 M?UPE
[SKDsJRPP
/** the total page number */ :%28*fl
privateint totalPage; 3DCR n :
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/** the number of current page */ ]4')H;'y
privateint currentPage;
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/** the begin index of the records by the current xe.f]a
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query */ ncVt(!c,e
privateint beginIndex; ~ e<,GUx(]
2t0VbAO1{
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/** The default constructor */ G^;]]Ji"
public Page(){ p_zVrlVb
b9wC:NgQx
} *Br
}U
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/** construct the page by everyPage qauvwAMuX
* @param everyPage QiqRx
* */ 1 K^-tms
public Page(int everyPage){ bz,"TG[
this.everyPage = everyPage; K0@bh/i/^
} 64y9.PY
MCXt,`}[
/** The whole constructor */ "*c&[ALw
public Page(boolean hasPrePage, boolean hasNextPage, 5ff5M=M
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int everyPage, int totalPage, )$pqe|,
int currentPage, int beginIndex){ vZ6R>f
this.hasPrePage = hasPrePage; P= E10
this.hasNextPage = hasNextPage; n c.P
this.everyPage = everyPage; U`{ M1@$
this.totalPage = totalPage; iHdX
this.currentPage = currentPage; jrm^n_6};
this.beginIndex = beginIndex; )5x$J01S
} b
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zQGj,EAM}
/** pJo4&Ff
* @return q}E'x/s2m
* Returns the beginIndex. 96gaun J
*/ &u) qw}
publicint getBeginIndex(){ ,&@FToR
return beginIndex; i4SWFa``
} ^R+CkF4l l
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/** '81Rwp
* @param beginIndex zR=g<e1xe
* The beginIndex to set. }$@K
*/ 5a&gdqg]
publicvoid setBeginIndex(int beginIndex){
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this.beginIndex = beginIndex; *@YQr]~
;
} v=IcVHuf
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/** 9q^7%b,
* @return Ml_!)b
* Returns the currentPage. x
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*/ Y~OyoNu2
publicint getCurrentPage(){ X(>aW*q
return currentPage; c,*a|@
} (Q|Y*yI
S~ y.>X3"P
/** ^$8WV&5q>
* @param currentPage Mi[,-8Sk
* The currentPage to set. Ez>!%Hpn\
*/ r+MqjdXG
publicvoid setCurrentPage(int currentPage){ t\ 9Y)d
this.currentPage = currentPage; lF$$~G
} G?+]BIiL
{5T:7*J
/** Z1DF )
* @return :XO7#P
* Returns the everyPage. g^k=z:n3,
*/ S|BS;VY
publicint getEveryPage(){ N)YoWA>#bF
return everyPage;
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} y)`q% J&
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/** 9sB LCZ
* @param everyPage uU8L 93
* The everyPage to set. \H/}|^+@
*/ #pMpGw$
publicvoid setEveryPage(int everyPage){ 9Cw !<
this.everyPage = everyPage; o@|kq1m8
} zvbz3 a
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/** #U/L8
* @return mP ^*nB@,
* Returns the hasNextPage. J2$=H1-
*/ V5]\|?=
publicboolean getHasNextPage(){ d#HN'(2t
return hasNextPage; FHZQyO<|
} ' ]vMOGG
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/** rj;~SC{
* @param hasNextPage G)7J$4R
* The hasNextPage to set. "I45=nf
*/ T;B/Wm!x
publicvoid setHasNextPage(boolean hasNextPage){ 7, :l\t
this.hasNextPage = hasNextPage; c *Pt;m
} lJBZ0
]+AgXUrbOD
/** jD_B&MQz
* @return KKJ a?e`C
* Returns the hasPrePage. >tV:QP]Y
*/ 3+:uV
publicboolean getHasPrePage(){ 'J#uD|9)
return hasPrePage; T04&Tl'CT
} uBBW2
iM s(Ywak]
/** fZJ O}
* @param hasPrePage %{";RfSVX%
* The hasPrePage to set. ^NOy:>
*/ BjbpRQ,
publicvoid setHasPrePage(boolean hasPrePage){ fn\&%`U
this.hasPrePage = hasPrePage; )]m_ L$9
} {]:B80I;2
Ty"=3AvRLV
/** =`BPGfCb
* @return Returns the totalPage. ,DWC=:@X
* N!=Q]\ZD
*/ 3 p9LVa
publicint getTotalPage(){ WevXQ-eKm
return totalPage; +N!!Z2
} vpqMKyy
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/** 3`\)Qm
* @param totalPage gT4H?
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* The totalPage to set.
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*/ 9w,u4q
publicvoid setTotalPage(int totalPage){ U})Z4>[bvt
this.totalPage = totalPage; ^Dhu8C(
} 834dsl+U
)v?-[
oR
} 0_5j(
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h ^6Yjy
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 * E3
c--
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个PageUtil,负责对Page对象进行构造: N8:&v
java代码: 0NWtu]9QC
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/*Created on 2005-4-14*/ N%&D(_
package org.flyware.util.page; We*)RXm%
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import org.apache.commons.logging.Log; ]tVXao
import org.apache.commons.logging.LogFactory; xiPP&$mg
&$</|F)y
/** zx{O/v
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* @author Joa #GHLF
* U)N_/
*/ p@7[w@B\c
publicclass PageUtil { s GP}>w-JZ
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privatestaticfinal Log logger = LogFactory.getLog 8oj-5|ct
){oVVLs
(PageUtil.class); 21BlLz
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/** Ilc FW
* Use the origin page to create a new page k98}Jx7J)"
* @param page :K6(`J3Y"^
* @param totalRecords d>Z{TFY
* @return q(yw,]h]{
*/ \ns#l@B
publicstatic Page createPage(Page page, int 4%I(Z'*Cx
[T.BK:
totalRecords){ 1+^L,-k!
return createPage(page.getEveryPage(), =R^V[zTn_
{-]/r
page.getCurrentPage(), totalRecords); E5M*Gs
} "=W7=V8w
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/** F=hfbCF5x
* the basic page utils not including exception ^J>jU`)CJ
F%6`D
handler ?6
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* @param everyPage 9 0[gXj
* @param currentPage R?Q@)POW
* @param totalRecords B*owV%
* @return page ud`.}H~aB
*/ r^?%N3
publicstatic Page createPage(int everyPage, int !o 7uZC\
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currentPage, int totalRecords){ d%9r"=/
everyPage = getEveryPage(everyPage); J|Lk::Ri
currentPage = getCurrentPage(currentPage); Qko}rd_M
int beginIndex = getBeginIndex(everyPage, 4.3Bz1p
V&_5q`L
currentPage); nYuZg6K
int totalPage = getTotalPage(everyPage, VYhZ0;' '
w<awCp
totalRecords); cmu5KeH
boolean hasNextPage = hasNextPage(currentPage, P$@5&/]
C/[2?[
totalPage); ;1cX|N=
boolean hasPrePage = hasPrePage(currentPage); (0"9562
AdB5D_ Ir
returnnew Page(hasPrePage, hasNextPage, odquAqn
everyPage, totalPage, e@L'H)w,
currentPage, Ckvm3r\i2
/
GJ"##<
beginIndex); u9>.x
zYG
} ;P _`4w3
r}QW!^F
privatestaticint getEveryPage(int everyPage){ >.#uoW4ZV
return everyPage == 0 ? 10 : everyPage; $+ZO{
(
} yaA9*k
}{Lf 4|8
privatestaticint getCurrentPage(int currentPage){ xN}P0
return currentPage == 0 ? 1 : currentPage; KI$?0O
} (^9q7)n
P,~a'_w:|D
privatestaticint getBeginIndex(int everyPage, int x-Z`^O
*Yvfp{B
currentPage){ lV$U!v:b
return(currentPage - 1) * everyPage; J
C1T033 r
} Os8]iNvW\
S53 [Ja
privatestaticint getTotalPage(int everyPage, int u3 ?+Hu|*T
*s?&)][
totalRecords){ E] t:_v
int totalPage = 0; Y.i<7pBt
akBR"y:~:H
if(totalRecords % everyPage == 0) ,h5.Si>
totalPage = totalRecords / everyPage; _QBd3B%
else cWp
n/.a
totalPage = totalRecords / everyPage + 1 ; C3bZ3vcW$
1w+&Y;d|
return totalPage; n4k.tq
} 9T|7edl
F^T7u?^)
privatestaticboolean hasPrePage(int currentPage){ mbd
return currentPage == 1 ? false : true; >}u?{_s *0
} xHykU;p@
tmK@Veb*a'
privatestaticboolean hasNextPage(int currentPage, )Ah
WqY:XE+?\
int totalPage){ <pYGcVB9V
return currentPage == totalPage || totalPage == ?8! 4!P%n
Ej 'a
G
0 ? false : true; A0O$B7ylQ
} qg:1
s4MP!n?gB
vxr3|2`
} !S%XIq}FX
|KU>+4=
@
gl.P#7X
bU2)pD!N
;n7k_K#0z!
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 Q`AJR$L
"Oh-`C
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 qdZn9i
c4L5"_#`x-
做法如下: XuR!9x^5
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 3{d1Jk/S
JZu7Fb]L9
的信息,和一个结果集List: $3Wl~
G}
java代码: 'n!;7*
oDM}h
+
dbE $T
/*Created on 2005-6-13*/ ,$W7Q
package com.adt.bo; k gWF@"_
)Q6R6xW
import java.util.List; x:@Ht TX
EiIbp4*e
import org.flyware.util.page.Page; (ioi !p
;se-IDN
/** . (Q;EF`_U
* @author Joa 8cR4@Hqx
*/ ykX}T6T
publicclass Result { f }eZX
:m^eNS6:
private Page page; $&k zix
pmIQD"
private List content; e!G
I<
$>8+t>|
/** _@jl9<t=_
* The default constructor 8$xg\l0?KK
*/ u|O5ZV-cd
public Result(){ xREqcH,vU
super(); 7cY_=X-?Y
} h^?[:XBeav
tlI3jrgw
/** !)_80O1
* The constructor using fields 'hf-)\Ylf
* SYeCz(H>d
* @param page e=1&mO?
* @param content }4
P@`>e/`
*/ m"X0Owx
public Result(Page page, List content){ p,$1%/m
this.page = page; >77
/e@
this.content = content; b3<<4Vf
} n]6xrsE
k]ptk^
/** 2,E&}a|;b
* @return Returns the content. 3Ki`W!C
*/ T_y 'cvh
publicList getContent(){ 9@:H9"w
return content; Euk#C;uBg
} O&E1(M|*>
J$j&j`
/** cQ1oy-paD
* @return Returns the page. !ck=\3pr
*/ ;BejFcb
public Page getPage(){ TW:vL~L
return page; 2W$c%~j$2
} ?K|PM<A
c{V0]A9VF
/** o8H<{D13
* @param content ORp6
* The content to set. y? )v-YGu
*/ fn&gM\<-+(
public void setContent(List content){ eLL>ThMyW
this.content = content; q'hMf?_
} Bl3G_Ep
E)NH6~
/** WK:~2m&y
* @param page `jvIcu5c
* The page to set. i8Y l1nF
*/ =LZj6'
publicvoid setPage(Page page){ PF1!aAvVb
this.page = page; ]J~37 35]
} 3k5Mty
} G0^23j
mhnD1}9,Ih
B.'@~$
d3&gHt2
jf$6{zO6j
2. 编写业务逻辑接口,并实现它(UserManager, {{tH$j?Q
&!N5}N&
UserManagerImpl) jF Bq>
java代码: agM.-MK
?*9U
d
JihI1C
/*Created on 2005-7-15*/ |Rhx&/
package com.adt.service; ^G~W}z?-
dV<M$+;s]
import net.sf.hibernate.HibernateException; (=QaAn,,R
{iYu
x;(
import org.flyware.util.page.Page; b+OLmd
qaA\.h7
import com.adt.bo.Result; *O)_D
bj
PxfeU2^{0
/** ":Kn@S'{(
* @author Joa ed'}ReLK
*/ fB3O zff
publicinterface UserManager { v|?hc'Fj
69dFd!G\
public Result listUser(Page page)throws hIXGfvUy
5y(irbk7
HibernateException; = EyxM
N>/*)Frt
} /JEH%)
cEsBKaN
YQ,IdWav
"f!*%SR:
1
H'q&1^w)
java代码: `RthX\Tof
;wL*
.x(&-
/*Created on 2005-7-15*/ pEH[fA]
package com.adt.service.impl; )_GM&-
9`4h"9dO
import java.util.List; >:W)9o
at,Xad\j
import net.sf.hibernate.HibernateException; \CUxGyu
qt^%jIv
import org.flyware.util.page.Page; t<ftEJU"'w
import org.flyware.util.page.PageUtil; $#]?\psf
2}$Vi$
R
import com.adt.bo.Result; ^nbze
import com.adt.dao.UserDAO; I;P?P5H
import com.adt.exception.ObjectNotFoundException; X2M<DeF:
import com.adt.service.UserManager; L9Fx
Lw41
*VHBTO9
/** {@Diig
* @author Joa u%XFFt5
*/ Ct }"o
publicclass UserManagerImpl implements UserManager { KS*W<_I
1G.+)*:3
private UserDAO userDAO; W.MJyem
R#Bt!RNZ
/** PO&xi9_
* @param userDAO The userDAO to set. oYJ&BPuA'
*/ *ivbk /8
publicvoid setUserDAO(UserDAO userDAO){ t$l[ 4
R-
this.userDAO = userDAO; P2`ks[u+i
} jvu,W4
$XyGCn
/* (non-Javadoc) _JR4
PKtx
* @see com.adt.service.UserManager#listUser h@{@OAu?
O])/kS`
(org.flyware.util.page.Page) et9c<'
*/ CvbY2_>Nh
public Result listUser(Page page)throws })mez[UmZ
{/QpEd>3+
HibernateException, ObjectNotFoundException { RK rBHqh@
int totalRecords = userDAO.getUserCount(); 5Qy,Pkje
if(totalRecords == 0) B@iIj<p~
throw new ObjectNotFoundException _F@FcFG1Z*
QO#ZQ~
("userNotExist"); @Cz1rKU^l
page = PageUtil.createPage(page, totalRecords); i3e|j(Gs4
List users = userDAO.getUserByPage(page); l_,8_u7G
returnnew Result(page, users); ;H:qDBH
} "Ww^?"jQ)
t:M>&r:BL
} =WO{h48]
K[?wP>s
A)`M*(~
9 z3Iwl
^xqh!
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 }\gpO0Ox
Pyyx/u+?@
询,接下来编写UserDAO的代码: N#[/h96F
3. UserDAO 和 UserDAOImpl: OcSLRN?t
java代码: 9R ugkGy
dDm<'30?*v
koqH~>ZtD
/*Created on 2005-7-15*/ pn
=S%Qf]
package com.adt.dao; {ld([
)L#I#%
import java.util.List; Q2fa]*Z5
HuK'tU#
import org.flyware.util.page.Page; c69C=WQ
DD~8:\QD
import net.sf.hibernate.HibernateException; ol:_2G2xQ
;c;;cJc!
/** `mWg$e,
* @author Joa Y:byb68
*/ ?iia
publicinterface UserDAO extends BaseDAO { Zmp ^!|=X!
RKBtwZx>f
publicList getUserByName(String name)throws #MBYa&Tw7
BRW
HibernateException; _C*}14
"3
c^=,@#
publicint getUserCount()throws HibernateException; ^$T>3@rDB
H7\EvIM=
publicList getUserByPage(Page page)throws 1$
l3-x
W}Z|v
M$
HibernateException; `GSfA0?
xUeLX`73
} \?GMtM,
M"V?fn'
:|fzGf
K}wUM^
VvPTL8Z
java代码: K(Cv9YQ
N}^\$sVu_
3N<FG.6
/*Created on 2005-7-15*/ +:^tppg
package com.adt.dao.impl; e<IT2tv>u
M/#<=XhA
import java.util.List; >Ks| yNJ
X#pE!mT
import org.flyware.util.page.Page; hsVWD,w
3
D+dM0wM
import net.sf.hibernate.HibernateException; .ipYZg'V
import net.sf.hibernate.Query; jT'1k[vJj
0P!6
.-XU
import com.adt.dao.UserDAO; ;up89a-,9
)WBTqML[
/** A3h[VnuG,
* @author Joa #Ok*Or
*/ B'&%EW]
public class UserDAOImpl extends BaseDAOHibernateImpl ~xzRx$vU
PCD1I98
implements UserDAO { U?H!:?,C
]3C7guWz
/* (non-Javadoc) =cg0o_q8
* @see com.adt.dao.UserDAO#getUserByName 3;#v$F8R
?mrG^TV^+r
(java.lang.String) K~C*4H:9
*/ Lymy/9
publicList getUserByName(String name)throws _kgw+NA&-H
*qGxQ?/
HibernateException { q]<cn2
String querySentence = "FROM user in class MSsboSxA
tE- s/
com.adt.po.User WHERE user.name=:name"; t|d9EC]c(
Query query = getSession().createQuery ~x`OCii
e=TB/W_
(querySentence); BEN=/
v
query.setParameter("name", name); I=|b3-
return query.list(); Wu9@Ecb
} r#3(;N{=
9>\s81^
/* (non-Javadoc) (*BQd1Z
* @see com.adt.dao.UserDAO#getUserCount() /J8y[aa
*/ fD]}&xc
publicint getUserCount()throws HibernateException { j:\MrYt0H
int count = 0; $#8dtF
String querySentence = "SELECT count(*) FROM i4&"-ujrm
MAQkk%6[g
user in class com.adt.po.User"; 9}jF]P*Q
Query query = getSession().createQuery $9j\sZj&
k*[["u^u]
(querySentence); pQ!NhzQ
count = ((Integer)query.iterate().next C/\)-^
Bc`jkO.q
()).intValue(); oxha8CF]D
return count; C%9;~S
} P=OHiG\z
odD^xg"L
/* (non-Javadoc) d dkh*[
* @see com.adt.dao.UserDAO#getUserByPage "k o?AUt
~DPjTR
(org.flyware.util.page.Page) 5IE 2&V
*/ c,:xm=&
publicList getUserByPage(Page page)throws P4-`<i]!S
# y%Q{
HibernateException { ,`ST Va-
String querySentence = "FROM user in class /GD4GWv :
)
wtVFG
com.adt.po.User"; xT6&;,|`
Query query = getSession().createQuery oi^2Pvauh
d[9c6C:<q
(querySentence); cah1'Y
query.setFirstResult(page.getBeginIndex()) *NHBwXg+
.setMaxResults(page.getEveryPage()); ]3uErnI
return query.list(); KCu @5`p
} 9JYrP6I!_
mrX 2w
} @*P$4c
5 0uYU[W
pLjet~2}iJ
K<TVp;N
ErIAS6HS'
至此,一个完整的分页程序完成。前台的只需要调用 (ZH5/VKp
3omFd#EP
userManager.listUser(page)即可得到一个Page对象和结果集对象 &'4{/Gz
91d@/z
的综合体,而传入的参数page对象则可以由前台传入,如果用 &/R`\(hEA
A(zF[\{]
webwork,甚至可以直接在配置文件中指定。 ?0
93'lA
~b;l08 <
下面给出一个webwork调用示例: d*Q:[RUf,
java代码: .@KpN*`KH
t>.1,'zb
4gbi?UAmX
/*Created on 2005-6-17*/ VtIPw&KHW
package com.adt.action.user; 7ADh
M0VC-\W7f
import java.util.List; ,S[,F0"%
3jR,lEJyj
import org.apache.commons.logging.Log; v|uY\Z
import org.apache.commons.logging.LogFactory; tgoOzk^
import org.flyware.util.page.Page; jm9J-%?
Q M7z
.
import com.adt.bo.Result; 1&N|k;#QS
import com.adt.service.UserService; H^_]' ~.
import com.opensymphony.xwork.Action; y
Nb&;E7 H
Pl^-]~
/** b[p<kMTir
* @author Joa f[v~U<\R
*/ 8&snLOU
-Q
publicclass ListUser implementsAction{ ^@f%A<
P5M+usx
privatestaticfinal Log logger = LogFactory.getLog rK&ofc]f$
wXw pKm
(ListUser.class); KY'"Mg^!
jCdKau&9
private UserService userService; .s$#: ls?
F jdh&9Zc
private Page page; "j|}-a
Q|eRek
privateList users; 9`{[J['V
lsmzy_gV7
/* QYDTb=h~
* (non-Javadoc) {MX_t/o=f
* SR>Sq2cW0
* @see com.opensymphony.xwork.Action#execute() dbU
*/
Z4'"*
publicString execute()throwsException{ X?$Eb
Result result = userService.listUser(page); e1{t qNJ
page = result.getPage(); [ d<|Cde
users = result.getContent(); Vja' :i
return SUCCESS; THQW8 V
} FM9b0qE
wbI(o4rXE
/** (omdmT%D
* @return Returns the page. pfg"6P
*/ ;}K1c+m!5V
public Page getPage(){ "Gcr1$xG8!
return page; Tp~yn
} #Q6wv/"Ub
Rz`<E97-
/** `{I,!to
* @return Returns the users. u]E% R&
*/ hX)r%v:
publicList getUsers(){ uW;Uq=UN
return users; 3leg,qd
} _ %&"4bm.
f&`v-kiAn=
/** #Vn=(U4}!_
* @param page /(n)I
* The page to set. cv:nlq)
*/ _KmpC>J+
publicvoid setPage(Page page){ ~'fa,XZ<
this.page = page; iBJ*6orz
} voQ, K9
y(.WK8
/** r_)-NOp
* @param users 7u5B/M!
* The users to set. ^ bM;C_<$f
*/ ?0[%+AD hM
publicvoid setUsers(List users){ 3Un/-4uL
this.users = users; ec1g7w-n
} 8SAz,m!W)
58e{WC
/** Zz?+,-$_*&
* @param userService 3=bzIU
* The userService to set.
u.hnQsM
*/ }r^MXv ~(
publicvoid setUserService(UserService userService){ D{BH~IM
this.userService = userService; vo71T<K
} MW*}+ PCY
} T>f-b3dk
1b|<
;SC|VcbyH
^"buF\3L
&<UOi@
上面的代码似乎看不出什么地方设置了page的相关初值,事实上, SmR*b2U
_IlL'c5
可以通过配置文件来进行配置,例如,我想每页显示10条记录,那 3'/wRK l
3&' STPpW
么只需要: kI[EG<N1k
java代码:
iI
^{OD
!uO|T'u0a
ZN4&:9M
<?xml version="1.0"?> 3"L$*toRA
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork ["L?t ^*G
n<hwstk
1.0//EN" "http://www.opensymphony.com/xwork/xwork- P{>T?-Hj
pu>LC6m3a
1.0.dtd"> |g;XC^!%=o
uwQ4RYz
<xwork> 5<a<!]|C
JK_$A;Q
<package name="user" extends="webwork- W}=2?vHV=
J|DWT+$#Z
interceptors"> m",bfZ
q?0goL
<!-- The default interceptor stack name 5N|77AAxK
w^p2XlQ<
--> V&}Z# 9Dx
<default-interceptor-ref )7`~U"r
G:&Q)_
name="myDefaultWebStack"/> (6A{6_p
U)l>#gf8
<action name="listUser" -/c1qLdQ
K=TW}ZO
class="com.adt.action.user.ListUser"> *u'`XRJU/
<param XhAcC
D{c>i`\G
name="page.everyPage">10</param> a=.db&;vY
<result V
C'-h~
ptyDv
name="success">/user/user_list.jsp</result> ( L\G!pP.
</action> 0C+yq'D~[
Q
EGanpz
</package> )^S^s>3
Z?c=t-yqp
</xwork> y'|W['
36WzFq#
((>3,%B`
*2
$m>N
e=)*O
zGd*Q5l
这样就可以通过配置文件和OGNL的共同作用来对page对象设置初值 O\F^@;]F6
5uJP)S?
了。并可以通过随意修改配置文件来修改每页需要显示的记录数。 FJ,\?ooGf
Doc'7P
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 zHc 4e
< Gy!i/
PSqtZN
b:5%}
)tI2?YIR
我写的一个用于分页的类,用了泛型了,hoho u3i|}`
(=tF2YBV
java代码: q{Ta?|x#
a0/n13c?G
y7IbE
package com.intokr.util; ))69a
yZ~eLWz
import java.util.List; vb. Y8[
vH?+JN"A
/** uZ`d&CEh
* 用于分页的类<br> &0
)xvZ
* 可以用于传递查询的结果也可以用于传送查询的参数<br> si!9Gz;
* 0jJ28.kOp
* @version 0.01 iI@Gyq=
* @author cheng vz#wP
*/ Zj+}T
public class Paginator<E> { qfP"UAc{/
privateint count = 0; // 总记录数 EBDC '^
privateint p = 1; // 页编号 mA] 84zO
privateint num = 20; // 每页的记录数 e<O;pM:
privateList<E> results = null; // 结果 )<x;ra^
77&^$JpM
/** _Dcc<-.
* 结果总数 Ibv_D$cT
*/ Yr"!&\[oz
publicint getCount(){ 9>[.=
return count; k.=S+#"}
} @a.6?.<L
Q1ABnacR
publicvoid setCount(int count){ [cTRz*\s
this.count = count; =S[FJaIu7
} Z*vpQBbu
8F`BJ6='
/** ]g8i>,G
* 本结果所在的页码,从1开始 ll<9f)
* A"bSNHCKF
* @return Returns the pageNo. %+7T9>+
*/ ]lB3qEn<
publicint getP(){ Ot2zhR )
return p; |?fW!y
} vzohq1r5
z7@(uIl=X
/** q(jkit~`A
* if(p<=0) p=1 %g]$Vfpy
* az\<sWb#
* @param p rKy-u
*/ V'Z&>6Z
publicvoid setP(int p){ e$ XY\{
if(p <= 0) zU4V^N'
p = 1; |Uy e>%*}4
this.p = p; i!1ho T$
} }:RT,<
]e@0T{!
/** ]M+VSU
* 每页记录数量 OD?y
*/ *gM,x4 Y
publicint getNum(){ j]!7B HC
return num; d4y9AE@k
} I+Ncmg )>
|P,zGy
/** qLQ <1>u
* if(num<1) num=1 (b/A|hl
*/ 3wN?|N
publicvoid setNum(int num){ L(WL,xnBy
if(num < 1) `j&0VIU>>
num = 1; 7xv4E<r2
this.num = num; O6m.t%*
} (|0.m8D~D
:mXGIRi
/** Snc;p
* 获得总页数 biK)&6|`sa
*/ W_[|X}lWP
publicint getPageNum(){ ,hpH!J'5f/
return(count - 1) / num + 1; [%j?.N
} qj~flw1:
F_A%8)N
/** ==QWwPpA
* 获得本页的开始编号,为 (p-1)*num+1 s<[A0=LH
*/ ;y>S7n>n:
publicint getStart(){ 1R0ffP]
return(p - 1) * num + 1; A}t %;V2
} r4O|()
s kN9O"^A
/** -PNi^
K_
* @return Returns the results. +hE',i.
*/ LHs-&
publicList<E> getResults(){ v8ba~
return results; )v[XmJ>H~o
} T vrk^!
4p.^'2m
public void setResults(List<E> results){ |u@+`4o
this.results = results; #SKfE
} ldA!ou7
>\V6+$cNp
public String toString(){ Zy^=fM
StringBuilder buff = new StringBuilder >(X#<`
qE )Y}oN
(); `E@kFJ(<On
buff.append("{"); ~12_D'8D[
buff.append("count:").append(count); !c%
buff.append(",p:").append(p); G6ayMw]OF
buff.append(",nump:").append(num); 9A~>`.y
buff.append(",results:").append u*2fP]n
4SgF,ac3r
(results); ?hnx/z+uT
buff.append("}"); S}[l*7
return buff.toString(); \V,c]I
} j~bAbOX12
"e 1wr
} yL6^\x
dL-i)F
OTj,O77k