Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 wO.T"x%X
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 $MhfGMk!'
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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 OiI29
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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 rrz^LD
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分页支持类: B:oE&Ahh{
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java代码: "!,)Pv
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package com.javaeye.common.util; D4Z7j\3a
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import java.util.List; JIatRc?g
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publicclass PaginationSupport { 4LXC;gZ
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publicfinalstaticint PAGESIZE = 30; tfIUH'Ez>
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privateint pageSize = PAGESIZE; YgV" *~
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privateList items; %t*KP= @
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privateint totalCount; #b,!N
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privateint[] indexes = newint[0]; !,<rW<&;
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privateint startIndex = 0; -[}Ah NYK
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public PaginationSupport(List items, int @Ta0v:Y
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totalCount){ Lky T4HC8n
setPageSize(PAGESIZE); sq_
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setTotalCount(totalCount); eNDc220b
setItems(items); "N3!!3
setStartIndex(0); X? 7s
} Yij_'0vZ
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public PaginationSupport(List items, int 6GMwB@ b
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totalCount, int startIndex){ nTv^][
setPageSize(PAGESIZE); &8HJ4Vj2
setTotalCount(totalCount); +8}8b_bgH
setItems(items); *RD<*l
setStartIndex(startIndex); ~--b#o{
} 6
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public PaginationSupport(List items, int \2 Yo*jE}
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totalCount, int pageSize, int startIndex){ V~7Oa2'#B
setPageSize(pageSize); wBCBZs$H
setTotalCount(totalCount); ^tL]QE?|
setItems(items); Mj W{JR)I
setStartIndex(startIndex); 0`4Fa^o]h
} =zW`+++3
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publicList getItems(){ Bq~?!~\?.
return items; i4<n#]1!t
} !-Uq#Ea0/
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publicvoid setItems(List items){ zB8J|uG
this.items = items; .Fx-$Yqy
} ~.Er
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publicint getPageSize(){ ^Sc48iDc
return pageSize; OzV|z/R2'
} ]Wn=Oc{F
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publicvoid setPageSize(int pageSize){ xJ^pqb
this.pageSize = pageSize; %'MR;hQsd8
} .*Axr\x3
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publicint getTotalCount(){ W]5sqtF;6
return totalCount; eC='[W<a.
} $-uMWJ)l
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publicvoid setTotalCount(int totalCount){ 7Ga'FT.F
if(totalCount > 0){ rsD?
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this.totalCount = totalCount; _]M:
int count = totalCount / k&= iye(
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pageSize; MC_i"P6a
if(totalCount % pageSize > 0) VrKFpFd
count++; l(3\ekU!
indexes = newint[count]; l8 XY
for(int i = 0; i < count; i++){ CTZ#QiNP
indexes = pageSize * to#T+d.(v
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} {^@qfkZz^
}else{ G3D!ifho.#
this.totalCount = 0; qb PC5v
} <-xu*Fc
} +ooQ-Gh
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publicint[] getIndexes(){ +IM6 GeH
return indexes; XBos^Q
} 71G00@&w9D
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publicvoid setIndexes(int[] indexes){ -O6\!Wo=-
this.indexes = indexes; aFDCVm%U|
} h5ZxxtGU
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publicint getStartIndex(){ u4~(0
return startIndex; nE"0?VNW$
} W C3b_ia
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publicvoid setStartIndex(int startIndex){ +zzS
if(totalCount <= 0) 8_uh2`+Bvb
this.startIndex = 0; PF]Vt
elseif(startIndex >= totalCount) EK}QjY[i
this.startIndex = indexes .KxE>lJbqM
sX#7;,Ft7
[indexes.length - 1]; % ^&D,
elseif(startIndex < 0) *Vp$#Rb
this.startIndex = 0; D}K/5iU]a
else{ 1#jvr_ ga
this.startIndex = indexes _R;+}1G/
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[startIndex / pageSize]; 7.(vog"I)
} MKr:a]-'f~
} DZ&AwF
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publicint getNextIndex(){ >}B~~C;
int nextIndex = getStartIndex() + z<s4-GJ)?
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pageSize; #mbl4a
if(nextIndex >= totalCount) 'q*:+|"
return getStartIndex(); E']Gh
else i
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return nextIndex; 9Jp"E5Ql)
} Tp%4{U/0`
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publicint getPreviousIndex(){ ^g*/p[
int previousIndex = getStartIndex() - <=&7*8u0+
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pageSize; +ywd(Tuzm
if(previousIndex < 0) eE[/#5tK
return0; ?mW;%d~]
else -cnlj
return previousIndex; *!x/ia9
} +hd1|qa4
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}
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抽象业务类 m#(ve1E
java代码: 8v']>5S]#
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/** g@7j<UY
* Created on 2005-7-12 !;YQQ<D
*/ #L,5;R{`
package com.javaeye.common.business; \^%5!
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import java.io.Serializable; ?4}EhXR(
import java.util.List; r.;(Kx/M
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import org.hibernate.Criteria; zVs|go>F
import org.hibernate.HibernateException; aXefi'!6
import org.hibernate.Session; QZ54Osdl
import org.hibernate.criterion.DetachedCriteria; yi/jZX
import org.hibernate.criterion.Projections; yD!V;?EnK
import J#y?^Qm$)<
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org.springframework.orm.hibernate3.HibernateCallback; "Z6: d"S`
import t#h<'?\E
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org.springframework.orm.hibernate3.support.HibernateDaoS 0yxMIX
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upport; Zm@
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import com.javaeye.common.util.PaginationSupport; X*'-^WM6
~ ]q^Akq
public abstract class AbstractManager extends 'E,Bl]8C5
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HibernateDaoSupport { <XxFR
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privateboolean cacheQueries = false; <~Tlx:
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privateString queryCacheRegion; l@om2|B
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publicvoid setCacheQueries(boolean Xsc5@O!
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cacheQueries){ :=tPC A=
this.cacheQueries = cacheQueries; a4}2^K
} p=(;WnsK
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publicvoid setQueryCacheRegion(String 3rZ" T
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queryCacheRegion){ VQvl,'z
this.queryCacheRegion = g~@0p7]Y
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queryCacheRegion; WLWE%bDP
} ?WX&,ew~
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publicvoid save(finalObject entity){ n]@+<TA<uA
getHibernateTemplate().save(entity); <nj[=C4v
} v=|BqG`
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publicvoid persist(finalObject entity){ 3HA$k[%7P
getHibernateTemplate().save(entity); [#td
} 05MtQB
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publicvoid update(finalObject entity){ E `)p,{T
getHibernateTemplate().update(entity); ]Nvtiw 6
} 0n,5"B
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publicvoid delete(finalObject entity){ v}]x>f
getHibernateTemplate().delete(entity); oA~m*|
} %1]2+_6
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publicObject load(finalClass entity, ;NRT
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finalSerializable id){ ~]/X,Cf
return getHibernateTemplate().load Hk\+;'PrN
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(entity, id); rA9x T`
} C<fNIc~.
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publicObject get(finalClass entity, ?4Z0)%6
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finalSerializable id){ )
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return getHibernateTemplate().get ]+':=&+:
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(entity, id); .KT+,Y
} c)SSi@<
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publicList findAll(finalClass entity){ RQ{w`>K
return getHibernateTemplate().find("from S/d})8~.
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" + entity.getName()); i&>,aiH@
} gH\r# wy|
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publicList findByNamedQuery(finalString dtM@iDljj
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namedQuery){ 2a=WT`xf?
return getHibernateTemplate 7Nwi\#o
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().findByNamedQuery(namedQuery); vEzzdDwi6
} jD^L <
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publicList findByNamedQuery(finalString query,
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finalObject parameter){ Ip4NkUI3T
return getHibernateTemplate sp**Sg)
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().findByNamedQuery(query, parameter); ITc/aX
} aG}9Z8D
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publicList findByNamedQuery(finalString query, }h_Op7.5D
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finalObject[] parameters){ EkSTN
return getHibernateTemplate &ApJ'uC
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().findByNamedQuery(query, parameters); EJWMr`zdn
} }7=a,1T
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publicList find(finalString query){ j|`{
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return getHibernateTemplate().find 4nl>&AV
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(query); {sm={q
} dBlOU.B
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publicList find(finalString query, finalObject {yb\p9q{Yo
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parameter){ J82{PfQ"
return getHibernateTemplate().find o@>c[knJ
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(query, parameter); xD\Km>|i
} Q"hI !PO+
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public PaginationSupport findPageByCriteria h{* O9O<
p fBO5Ys
(final DetachedCriteria detachedCriteria){ _kY5
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return findPageByCriteria zi?'3T%Ie
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); AVyZ#`,
} MW`a>'0t?
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public PaginationSupport findPageByCriteria "}OFwes
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(final DetachedCriteria detachedCriteria, finalint /2@%:b)
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startIndex){ ;n;^f&;sJ
return findPageByCriteria =` i 7?
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(detachedCriteria, PaginationSupport.PAGESIZE, 9>i6oF]Oq
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startIndex); VNYLps@4H
} <Y#R]gf1
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public PaginationSupport findPageByCriteria m|]^f;7z
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(final DetachedCriteria detachedCriteria, finalint :>X7(&j8
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pageSize, li%-9Jd
finalint startIndex){ w@: ]]R
return(PaginationSupport) nUd\4;J#
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getHibernateTemplate().execute(new HibernateCallback(){ m_(hCY=Q$
publicObject doInHibernate i52R,hz
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(Session session)throws HibernateException { EORRSP,$2
Criteria criteria = vfv5ex(
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detachedCriteria.getExecutableCriteria(session); Wl#^Eu\g1W
int totalCount = {;4PP463
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((Integer) criteria.setProjection(Projections.rowCount t<|s&
.u*].As=
()).uniqueResult()).intValue(); FqsjuU@l
criteria.setProjection M=WE^v!b
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(null); X{xJ*T y'
List items = ~|9LWp_
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criteria.setFirstResult(startIndex).setMaxResults XC1lo4|
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(pageSize).list(); 9,5II0N L
PaginationSupport ps = 62x< rph
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new PaginationSupport(items, totalCount, pageSize, $M`;."
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startIndex); is?&%VY
return ps; _<a)\UR
} i 9tJHeSm
}, true); wDhcHB
} 'h^DI`
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public List findAllByCriteria(final C5 5n
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DetachedCriteria detachedCriteria){ 7=.VqC^
return(List) getHibernateTemplate Z{
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().execute(new HibernateCallback(){ &8AS=v
publicObject doInHibernate >v_5xd9
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(Session session)throws HibernateException { !;*2*WuO;
Criteria criteria = ,*Z[P%<9
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detachedCriteria.getExecutableCriteria(session); OPY/XKyY,
return criteria.list(); 'HWgvmw(
} bus=LAJt=
}, true); K2rS[Kdfaq
} ,okJ eZ
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public int getCountByCriteria(final z){UuiUM+=
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DetachedCriteria detachedCriteria){ %H}Y]D~R
Integer count = (Integer) Mto~ /
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getHibernateTemplate().execute(new HibernateCallback(){ N^yO- xk
publicObject doInHibernate UVCMB_T
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(Session session)throws HibernateException { oZ>`Qu
Criteria criteria = +Q!xEfpO;
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detachedCriteria.getExecutableCriteria(session); !bV(VRbu
return #8f"}>U9.,
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criteria.setProjection(Projections.rowCount :y-0qzD?
e=]oh$]
()).uniqueResult(); A[ECa{v
} ckjVa\
}, true); Ddl% V7
return count.intValue(); Bd oC6H
} k *;{n8o?)
} d! QD vO
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#:vDBP05.m
用户在web层构造查询条件detachedCriteria,和可选的 v_ nBh,2
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 n#^?X
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PaginationSupport的实例ps。 kJvy<(iG
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ps.getItems()得到已分页好的结果集 O^R:_vb3I
ps.getIndexes()得到分页索引的数组 gKs/T'PW
ps.getTotalCount()得到总结果数 Q 9gFTLQ
ps.getStartIndex()当前分页索引 IGK_1@tq
ps.getNextIndex()下一页索引 Y0L5W;iM
ps.getPreviousIndex()上一页索引 _5U%'\5s
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 PQ&Q71
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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 FU(}=5n
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一下代码重构了。 ^iV`g?z
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我把原本我的做法也提供出来供大家讨论吧: A^4kYOe
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首先,为了实现分页查询,我封装了一个Page类: vNK`Y|u@
java代码: ezg^5o;
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/*Created on 2005-4-14*/ u1pc5 Y{
package org.flyware.util.page; Gdf1+mi
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/** %TW%|"v
* @author Joa ~`~%(DA=
* z)ft3(!
*/ 0279g
publicclass Page { 2Z/][?Jj{
9+'@
/** imply if the page has previous page */ M}=s3[d(,
privateboolean hasPrePage; #7-kL7 MK]
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/** imply if the page has next page */ 0\EpH[m}-
privateboolean hasNextPage; k%Ma4_Z
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/** the number of every page */ GCP{Z]u
privateint everyPage; Q3NPwM
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/** the total page number */ B@"SOX
privateint totalPage; k W<Yda<a
pB g|n=^
/** the number of current page */ b"R, p=M
privateint currentPage; 8 l'bRyuS
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/** the begin index of the records by the current b(.-~c('
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query */ ih+*T1#:(
privateint beginIndex; IFd )OZ5
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/** The default constructor */ .6O52E
public Page(){ 97qtJ(ESI
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} )(:+q(m
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/** construct the page by everyPage L;1$xI8tx
* @param everyPage u%6Irdx
* */ sorSyuGr
public Page(int everyPage){ h`
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this.everyPage = everyPage; =~GE?}.o
} yCF"Z/.
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/** The whole constructor */ <mv7HKVg
public Page(boolean hasPrePage, boolean hasNextPage, 8iMF 8\
bx hP jAL
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int everyPage, int totalPage, Af2=qe
int currentPage, int beginIndex){ EX`"z(L
this.hasPrePage = hasPrePage; 0t#NMW
this.hasNextPage = hasNextPage; ^%\)Xi
this.everyPage = everyPage; F[>7z3I
this.totalPage = totalPage;
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this.currentPage = currentPage; :r1;}hIA9
this.beginIndex = beginIndex; U}tl_5%)
} x4CtSGG85f
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/** T"L0Iy!k;
* @return :V&N\>Wo
* Returns the beginIndex. [D*J[?yt
*/ +3M$3w{2
publicint getBeginIndex(){ eV[`P&j_C
return beginIndex; P'a0CE%
} qn2o[x
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/** L*zbike
* @param beginIndex 0lX)Cl
* The beginIndex to set. mgi,b2
*/ 6B7<
publicvoid setBeginIndex(int beginIndex){ 1vB-M6(
this.beginIndex = beginIndex; eq^TA1>T
} vS7/ ~:C
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/** 6-mmi7IfO
* @return DRH'A!r!
* Returns the currentPage. =?=)s
*/ ^y:FjQC:
publicint getCurrentPage(){ T?W[Z_D
return currentPage; nqZA|-}
} W3 ^z Ij
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/** p]wP36<S!
* @param currentPage uz ]E_&2
* The currentPage to set. :|Z$3q
*/ R;H?gE^m-
publicvoid setCurrentPage(int currentPage){ 1a<]$tZk
this.currentPage = currentPage; (7IqY1W
} <A)+|Y"^h6
Vo #:CB=8
/** jr9&.8%W:v
* @return M6J/mOVx5
* Returns the everyPage. zL9VR;q
*/ ~}h^38
publicint getEveryPage(){ ~_'0]P\
return everyPage; Y.q>EUSH
} o[o:A|n
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/** J#0GlK@"
* @param everyPage 2< p{z
* The everyPage to set. I^WIa"u_
*/ fs&,w
publicvoid setEveryPage(int everyPage){
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this.everyPage = everyPage; pJd 0k"{
}
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/** U);OR
* @return 4py(R-8\
* Returns the hasNextPage. 1 ojhh7<
*/ bFSlf5*H
publicboolean getHasNextPage(){ hF2/
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return hasNextPage; ,:^
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} Ejq=*UOP
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/** vK(I3db!
* @param hasNextPage J2r1=5HS
* The hasNextPage to set. C*7!dW6
*/ .AXdo'&2i
publicvoid setHasNextPage(boolean hasNextPage){ [(1O"
this.hasNextPage = hasNextPage; UV4u.7y
} O7v]p
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/** iSlFRv?a
* @return CD} Ns
* Returns the hasPrePage. Yb}w;F8(
*/ 3wZ(+<4i
publicboolean getHasPrePage(){ i|%5
return hasPrePage; Sr&T[ex,.
} N=#4L$@-
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/** }&1Iyb
* @param hasPrePage *wwhZe4V
* The hasPrePage to set. vXb:
*/ $_)=8"Sn
publicvoid setHasPrePage(boolean hasPrePage){ ,<sm,!^<r
this.hasPrePage = hasPrePage; {DT4mG5
} aM$\#Cx
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/** >Dne? 8r
* @return Returns the totalPage. +e'X;
* 7IW> >RBF
*/ Y;,Hzmbs6w
publicint getTotalPage(){ l)Zs-V!M^\
return totalPage; 8Y#bN*!
} %w7m\nw@
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/** JvkL37^n:
* @param totalPage h~w4, T
* The totalPage to set. W
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*/ azo0{`S?
publicvoid setTotalPage(int totalPage){ < A?<N?%o
this.totalPage = totalPage; 8%[HYgd5)
} B;!f<"a8
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} RZO5=L9E
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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 ' "'Btxz
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个PageUtil,负责对Page对象进行构造: jJ~Y]dQi
java代码: zE`R,:VI
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/*Created on 2005-4-14*/ 8Bpip
package org.flyware.util.page; Q.k
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c.C
import org.apache.commons.logging.Log; ]>Si0%
import org.apache.commons.logging.LogFactory; i[150g?K
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/** %jEY3q
* @author Joa <tbZj=*O/o
* i"HgvBHx
*/ 9cd 8=][
publicclass PageUtil { K)S;:MLG=
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privatestaticfinal Log logger = LogFactory.getLog ]` ]g@v
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(PageUtil.class); kq-6HDR
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/** 5)'P'kVi7.
* Use the origin page to create a new page o2=A0ogz?
* @param page K=6UK%y
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* @param totalRecords `HW:^T
* @return Ftv8@l
*/ (ZP87Gz
publicstatic Page createPage(Page page, int ->E=&X
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totalRecords){ LK}-lZ`
i
return createPage(page.getEveryPage(), )NT5yF,m
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page.getCurrentPage(), totalRecords); <y)E>Fl
} 7zDiHac
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/** S#8>ZwQ
* the basic page utils not including exception w#(RW7":F
],lV}Mlg*
handler 5H lWfD
* @param everyPage ?znSx}t
* @param currentPage ?a.+j8pbGg
* @param totalRecords @Bs0Avj.
* @return page dDtFx2(R
*/ 0^~\COa
publicstatic Page createPage(int everyPage, int f9TV%fG?
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currentPage, int totalRecords){ UG2w 1xqHw
everyPage = getEveryPage(everyPage); pOga6'aB)
currentPage = getCurrentPage(currentPage); T_#,
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int beginIndex = getBeginIndex(everyPage, TJy4<rb
8#LJ* o
currentPage); PRs@zkO
int totalPage = getTotalPage(everyPage, kzO&24
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totalRecords); uDayBaR
boolean hasNextPage = hasNextPage(currentPage, 0ys~2Y!eH
m)&znLA
totalPage); 3HiFISA*
boolean hasPrePage = hasPrePage(currentPage); 5bX6#5uP1
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returnnew Page(hasPrePage, hasNextPage, ?o[L7JI
everyPage, totalPage, =_pwA:z"A
currentPage, 7#-y-B]l
.FP$ IWt/1
beginIndex); B|o%_:]+E
} SR7j\1a/2A
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privatestaticint getEveryPage(int everyPage){ JlZ0n;
return everyPage == 0 ? 10 : everyPage; l]#!+@
} MagMZR
g+[kde;(^
privatestaticint getCurrentPage(int currentPage){ O`W%Tr
return currentPage == 0 ? 1 : currentPage; z,f=}t[.Y
} (36K3=Q a
`
2%6V)s
privatestaticint getBeginIndex(int everyPage, int SUdm 0y
A7-r<s
currentPage){ JMyTwj[7
return(currentPage - 1) * everyPage; %c/^_.
} YD[H
pGWA\}'
privatestaticint getTotalPage(int everyPage, int @}LZ! y
Nhf~PO({&
totalRecords){ O!R"v'
int totalPage = 0; #V_GOy1-
6Wf^0ok
if(totalRecords % everyPage == 0) HFtf
totalPage = totalRecords / everyPage; QT!5l`
else 45+{nN[
totalPage = totalRecords / everyPage + 1 ; eti`O
Fi;VDK(V9
return totalPage; /g.]RY+u|x
} s:|M].
" 'tRfB
privatestaticboolean hasPrePage(int currentPage){ l?E|RKp
return currentPage == 1 ? false : true; wD9a#AgEd
} (.X]F_*sc
]qktj=p
privatestaticboolean hasNextPage(int currentPage, {BV4h%P]:
t9
F=^)s
int totalPage){ yp]@^T N
return currentPage == totalPage || totalPage == Zk`#VH
Z[L5 ;
0 ? false : true; !~ rt:Z
} W{Q)-y
P%>?[9!Nt
+"!aM?o
} k
onoI&kV|
I$jvXl=$
H~fdbR
(xT*LF+
AXW!]=?X
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。 $k0H9_
zVaCXNcbo
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 uofLhy!
q)I|2~Q c^
做法如下: PZOKrW
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 "4 k-dj
5cTY;@@
的信息,和一个结果集List: f&I7,"v
java代码: ^ddO&!U
5K.+CO<
kX;$}7n
/*Created on 2005-6-13*/ zhsx&
package com.adt.bo; |f' 8p8J
{B{i(6C(
import java.util.List; G[yI*/E;
|E^|X!+9
import org.flyware.util.page.Page; 7
.+al)hl
ZKdh%8C
/** O%JSViPw
* @author Joa x)viY5vjH
*/ TOT
PzB
publicclass Result { p:[LnL
!v>ew9
private Page page; fluGf
c> ~:dcy
private List content; JAP(|
uxDLDA$;
/** X47!E
|*
* The default constructor nNR:cGfG
*/ DY3:#X`4
public Result(){ 04JT@s"o
super(); J(9=T<%T
} kL;t8{n
O
E|+R4M
/** -!R
l(if
* The constructor using fields UR:n5V4
* JlIS0hnv
* @param page $u5.!{Wq?
* @param content l l:jsm
*/ x[Q&k[xV
public Result(Page page, List content){ SIv[9G6
this.page = page; ^
f{qJ[,
this.content = content; Q8Te'1Ln!
} l1RlYl5
`|,tCM&-
/** yJ J8"s~i
* @return Returns the content. X_?%A54z?
*/ az
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publicList getContent(){ CWMlZVG
return content; ~@fanR =
} OqEHM%j
RKk"
/** l $ Zs~@N
* @return Returns the page. J/7u7_
*/ M?hFCt3Y
public Page getPage(){ <2)v9c
return page; Xz* tbW#
}
5KaSWw/
9|a)sb7/
/** %kW3hQ<$
* @param content 8Mb$+^zU
* The content to set. C$y fMK,,N
*/ >fwlg-
public void setContent(List content){ /cY[at|p
this.content = content; h7RD`k:mF
} P^;WB*V
Z@nmjj i
/** n}5x-SxS0
* @param page YiNo#M91
* The page to set. c#x7N9;"!
*/ p[gAZ9
publicvoid setPage(Page page){ 2K~tDNv7
this.page = page; LOt#1Qv
} U]mO7 HK
} #VR`?n?,
]E..43
l~{T#Q
qL~Pjr>cF
/0!$p[cjm
2. 编写业务逻辑接口,并实现它(UserManager, v/(__xN`B
TP^\e_k
UserManagerImpl) lmp
R>@o"
java代码: =ZrjK=K
NN*Sb J0
>oB ?
/*Created on 2005-7-15*/ yEnKUo[
package com.adt.service; 2}@*Ki7
KK .cDAR
import net.sf.hibernate.HibernateException; s9kTuhoK
wEv*1y4
import org.flyware.util.page.Page; jaNH](V
'[xut1{
import com.adt.bo.Result; A7e_w
7?a
Qvs(Rt3?y
/** WT1q15U(=
* @author Joa *IVD/9/
*/ s'2y%E#
publicinterface UserManager { &U854
ur`}v|ZY
public Result listUser(Page page)throws "SDsISWd
AF
QnCl Of
HibernateException; Q!M sy<v
>sB=\
} LsUFz_
739l%u }<
8Q)y%7{6
?n73J wH
YU*46 hA1B
java代码: _4!7
zW^
?|gGsm+
WMRYT"J?N]
/*Created on 2005-7-15*/ 8UlB~fVg
package com.adt.service.impl; .Wd.)^?
E)RI!0Ra
import java.util.List;
-kV|
)lE3GDAPgZ
import net.sf.hibernate.HibernateException; j(UX
6lR
6Lav.x\W
import org.flyware.util.page.Page; |UABar b
import org.flyware.util.page.PageUtil; av7q>NEZ!1
Vl&+/-V
import com.adt.bo.Result; he_HVRpB
import com.adt.dao.UserDAO; 0 [*nAo
import com.adt.exception.ObjectNotFoundException; -aTg>Q|g&
import com.adt.service.UserManager; a [0N,t
\>w@=bq26
/** EgkZ$ah
* @author Joa Y^T-A}?`
*/ k?z
[hZg0
publicclass UserManagerImpl implements UserManager { X*43!\
/QM0.{Ypl
private UserDAO userDAO; 8Q#t\$RY
!tm|A`<g#<
/** =kyJaT^5[
* @param userDAO The userDAO to set. O[3q9*(
*/ a-SB1-5jf
publicvoid setUserDAO(UserDAO userDAO){ {^2({A#&
this.userDAO = userDAO; 4UkP:Vz:
} ?Aj\1y4L1
]JGKL5~p
/* (non-Javadoc) IiYuUN1D
* @see com.adt.service.UserManager#listUser e_;%F`
hCSRsk3
(org.flyware.util.page.Page) W ??;4
*/ QYFN:XZ
public Result listUser(Page page)throws iA5*
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1gf/#+$\
HibernateException, ObjectNotFoundException { w}]3jc84
int totalRecords = userDAO.getUserCount(); n-L]YrDPK[
if(totalRecords == 0) K gR1El.r
throw new ObjectNotFoundException HCfS)`
hqwz~Ky}
("userNotExist"); 3ZT/>a>@
page = PageUtil.createPage(page, totalRecords); 0e[ tKn(
List users = userDAO.getUserByPage(page); L|dab{9
returnnew Result(page, users); WW,r9D:/
} \" 5F;J
!nZI? z ;
} a3DoLq"/
W]C_oh
LRfFn^FPM
/It.>1~2@
FE^?U%:u@
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 D0,oml
}bj,&c
询,接下来编写UserDAO的代码: )w3XN A_V
3. UserDAO 和 UserDAOImpl: !>"INmz
java代码: f@,hO5h(_|
+dPE!:
OsHkAI
/*Created on 2005-7-15*/ PW~cqo B71
package com.adt.dao; .q~,.yI&j
#b<lt'gC
import java.util.List; T-<> )N5y
uv_P{%TK
import org.flyware.util.page.Page; ;mM\,
{Z
6+{ nw}e8
import net.sf.hibernate.HibernateException; iq[2H$
o} bj!h]N
/** #I*ht0++
* @author Joa 7csl1|U
*/ /3"e3{uy
publicinterface UserDAO extends BaseDAO { oIu,rjb
o
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publicList getUserByName(String name)throws &
Q|f *T
iZVT% A+q
HibernateException; ;]8p:ME
H/ B^N,oi
publicint getUserCount()throws HibernateException; CC]@`R5
Is#v6:#^
publicList getUserByPage(Page page)throws U:T5o]P<
cZ7F1H~
HibernateException; b5iJm-
JOL Z2
} e[|p0 ,Q
o@Cn_p^X
R`<{W(J;r
$`+~QR!h
F".IB^}$
java代码: {0m[:af&
1)c=15^
Vq;{+j(
/*Created on 2005-7-15*/ N5I W@?4
package com.adt.dao.impl; B@~eBU,$
njx\$,ruN
import java.util.List; O#89M%
p-i]l.mT5
import org.flyware.util.page.Page; *T}dv)8
6nhfI\q3wY
import net.sf.hibernate.HibernateException; pCud`
:o"
import net.sf.hibernate.Query; |Jx2"0:M
3YZ3fhpw
import com.adt.dao.UserDAO; /:c,v-
UmHJ/DI@
/** @,f,tk=\S
* @author Joa J*W;{Vty
*/ `HZHVV$~
public class UserDAOImpl extends BaseDAOHibernateImpl E&Zx]?~
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implements UserDAO { ~wd?-$;070
@"#gO:|[i0
/* (non-Javadoc) Wb-'E%K
* @see com.adt.dao.UserDAO#getUserByName '~vSH9nx/
.ubbNp_LU
(java.lang.String) ?28G6T]/?d
*/ TVEF+t
publicList getUserByName(String name)throws 2>_LX!kyP]
n46PQm%p
HibernateException { .4m3@!qo)E
String querySentence = "FROM user in class )]e d;V
QIxJFr;>
com.adt.po.User WHERE user.name=:name"; ]t!}D6p
Query query = getSession().createQuery T_|fb)G+{
Dg2#Gv0B
(querySentence); [3;Y:&D
query.setParameter("name", name); C&#KdvN/r
return query.list(); uEi.nSp)S
} &>^Ympr
8"I5v(TV
/* (non-Javadoc) ( ;S]{z%
* @see com.adt.dao.UserDAO#getUserCount() C
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*/ 9#$V1(}?
publicint getUserCount()throws HibernateException { o dQ&0d
int count = 0; :?of./Df|
String querySentence = "SELECT count(*) FROM WaZ@
w<^2h}5
user in class com.adt.po.User"; t2%bHIG}
Query query = getSession().createQuery o\V4qekk
!gH.st
(querySentence); !6i
count = ((Integer)query.iterate().next '~x_
#Ew
eG^!#
()).intValue(); HW%bx"r+4f
return count; NBR'^6
} 4lo}-@j
>j~70 ?
/* (non-Javadoc) ,IX4Zo"a
* @see com.adt.dao.UserDAO#getUserByPage FO)nW:8]
LRlk9:QD>
(org.flyware.util.page.Page) ^V;lZtZ
*/ Ognq*[om
publicList getUserByPage(Page page)throws W&q5cz
^xu)~:} i
HibernateException { JdNPfkOF
String querySentence = "FROM user in class nhaoh!8A6
w5JC 2
com.adt.po.User"; gJcL{]
Query query = getSession().createQuery O5n]4)<
BE@H~<E J
(querySentence); RBojT
query.setFirstResult(page.getBeginIndex()) vBQ?S2f
.setMaxResults(page.getEveryPage()); yDBgSO{d
return query.list(); u2Z^iY
} {(:)
.`8,$"`4)
} ?g1.-'
DB=cc
#3ro?w
lkJ#$Ik&
Vy"^]5
至此,一个完整的分页程序完成。前台的只需要调用 !(AFT!
MvwJ(3
userManager.listUser(page)即可得到一个Page对象和结果集对象 K OHH74}_
s 17gi,"X
的综合体,而传入的参数page对象则可以由前台传入,如果用 OM C|.[
Kpbber
webwork,甚至可以直接在配置文件中指定。 @<{#v.T
wI]>0geb*
下面给出一个webwork调用示例: hp%Pg &
java代码: lcJumV=%>
+OP:"Q_#
,]N%(>ot
/*Created on 2005-6-17*/ >knR>96
package com.adt.action.user; G:s:NXy^
jWmBUHCb
import java.util.List; >$9yQ9&|
B{i;+[ase
import org.apache.commons.logging.Log; uWT&`m_(2
import org.apache.commons.logging.LogFactory; 49kia!FR
import org.flyware.util.page.Page; `r bqYU0
G~L#vAY
import com.adt.bo.Result; C+IE<=%F
import com.adt.service.UserService;
gMMd=
import com.opensymphony.xwork.Action; @+vTGjHA
Kt7x'5
/** Ln
-?/[E
* @author Joa ~ab_+%
*/ 9
3I9`!e
publicclass ListUser implementsAction{ $?Mz[X
V zx(J)
privatestaticfinal Log logger = LogFactory.getLog bo/!u
s#
rNO;yL4)ey
(ListUser.class); 8"rX;5
vP
jmNj#R@t
private UserService userService; kO>{<$
lR3^&d72?
private Page page; ~7H.<kJt
;;H:$lx
privateList users; \r9%;?f
QQ8W;x
/* #I wB
* (non-Javadoc) /Day5\Q#
* {j@)sDMX
* @see com.opensymphony.xwork.Action#execute() ?b$zuJ]
*/ 7C
yLSZ
publicString execute()throwsException{ !/Ps}.)A`
Result result = userService.listUser(page); LX&P]{qKS
page = result.getPage(); ^$
bhmJYT
users = result.getContent(); 9\0 K%LL
return SUCCESS; ;z=C]kI6M
} \Y 4Z Q"0Q
X'4
Yofs
/** ]V("^.~$+C
* @return Returns the page. RN|..zml
*/ VMXXBa&
public Page getPage(){ pa73`Ca]
return page; x)5v8kgf
} 3]'z8i({7Y
/RmCMT
/** B K;w!]
* @return Returns the users. !AHm+C_=Lg
*/ _q$fw&
publicList getUsers(){ `roSOX1f
return users; Oei2,3l,?
} (%!R
m(P)oqwM
/** c!T{|'?
* @param page sn#h=,*4`
* The page to set. Al]9/ML/m
*/ Q7%#3ML
publicvoid setPage(Page page){ 8hp]+k_y
this.page = page; o>tT!8rH
} t1^96@m^
Xlw=R2`)~
/** 8[ OiG9b
* @param users 2ow\d b
* The users to set. k~dr;j
*/ 4Pdk?vHK;
publicvoid setUsers(List users){ (Mh\!rMg
this.users = users; [40 YoVlfM
} FCPRg^=<!~
'b,D;'v
/** c y$$}
* @param userService r&DK> H
* The userService to set. `pUArqf
*/ C%>7mz-v5
publicvoid setUserService(UserService userService){ lhTbg M
this.userService = userService; _F EF+I
} uSjMqfK
} X_F= ;XF/
e{:qW'%
S8,06/#
I SmnZ@
V:J6eks_
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, Uo
,3 lMr
N!,l4!M\N
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 Yv-uC}e
k:xV[9ev:
么只需要: Akf9nT
java代码: RI;RE/Z
,Pm/ci(s
}tPl?P'`
<?xml version="1.0"?> ^S|^1
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork CcTJCuOS
4+ gA/<
1.0//EN" "http://www.opensymphony.com/xwork/xwork- ~s_$a8
^B9wmxe
1.0.dtd"> 3!L)7Z/
'c D"ZVm1
<xwork> 8<xy*=%
ffVYlNQ7L
<package name="user" extends="webwork- !%@{S8IP.v
!
N p
interceptors"> \m!."~%
6dUP's_
<!-- The default interceptor stack name H<yec"
JGe;$5|q8
--> 2<|5zF
<default-interceptor-ref m}(DJ?qP
G#Ow>NJ
name="myDefaultWebStack"/> 0l6%[U?o
]Y?$[+Y
<action name="listUser" CmZ?uo+Y
C*!_. <b
class="com.adt.action.user.ListUser"> 10&A3C(E
<param m.*+0NG
Q~kwUZ
name="page.everyPage">10</param> u4'Lm+&O
<result uJ$,e5q
z4goa2@Z
name="success">/user/user_list.jsp</result> G`z48
</action> Su7?-vY
lzuZv$K
</package> HChewrUAn
7d*<'k]{,
</xwork> s7?kU3y=s
~6nQ-
N_0O"" d
GZw<Y+/V"5
wkGF&U
?8 F7BS4oQ
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 Yq_zlxd%F
~gc)Ww0(Q
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。 {~"=6iyj
}!LYV
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 P,wJ@8lv
0)NHjKP
l?q^j;{Dw
P
dJ*'@~i
^:#%TCJ
我写的一个用于分页的类,用了泛型了,hoho pLU>vQA
F\e'z
java代码: QbWD&8T0O
&,/T<V
@'<|B. f
package com.intokr.util; 82vx:*Ip!}
UgP5^3F2
import java.util.List; [F%\1xh
%YXC-E3@O
/** w~9gZ&hdp
* 用于分页的类<br> Z%Gvf~u
* 可以用于传递查询的结果也可以用于传送查询的参数<br> OW>U5 \q
* TwN8|ibVmP
* @version 0.01 -h_v(s2
* @author cheng #E1*1E
*/ 5c#L6 dA)
public class Paginator<E> { b}
*cw2
privateint count = 0; // 总记录数 +CkK4<dF
privateint p = 1; // 页编号 q)[gVL
privateint num = 20; // 每页的记录数 9&tV#=s
privateList<E> results = null; // 结果 J}x5Ko@
!ZVMx*1Cf
/** j405G4BVW
* 结果总数 vcmS]$}
*/ b6lL8KOu
publicint getCount(){ dw-r}Qioe
return count; F8/@/B
} `y\:3bQ4
4u&doSXR
publicvoid setCount(int count){ 4aRYz\yT=
this.count = count; BhKxI
} TuU.yvkU
/vhh2`
/** ax<0grK
* 本结果所在的页码,从1开始 2'_sGAH
* Rq*m x<HDX
* @return Returns the pageNo. .28*vkH%C=
*/ Q3DxjD
publicint getP(){ =[WccF
return p; _D:/?=y;e
} 5v3B8 @CsA
n RGH58
/** ^vPa{+N
* if(p<=0) p=1 f6XWA_[i@
* uO6_lOT9n
* @param p S8y4 p0mV
*/ im'0^
publicvoid setP(int p){ T:ck/:ZH
if(p <= 0) 5HU>o|.
p = 1; 2{&" 3dq
this.p = p; J4gIkZD
} >3bpa<M_
>|s=l`"Xz
/** #GF1MFkoS
* 每页记录数量 >M!>Hl/
*/ JG_7G=~
publicint getNum(){ ()?)Ybqss
return num; ':,LZ A8A
} @l?%]%v|
J+zqu
/** iqU}t2vFrj
* if(num<1) num=1 M3Z yf
*/ UY+~xzm
publicvoid setNum(int num){ /b*@dy
if(num < 1) kC+A7k6
num = 1; X;1q1X)K
this.num = num; ;2iZX=P`n
} TnG"_VK9R
IV*}w"r
/** p+t8*lkq
* 获得总页数 {T IGPK
*/ i~2>kxf;K1
publicint getPageNum(){ t@ Jo ?0s
return(count - 1) / num + 1; ``SjALf
} 7Ct m({I-
E,r PM
/** )#Id2b~
* 获得本页的开始编号,为 (p-1)*num+1 UJZa1p@L
*/ {R#nGsrt;
publicint getStart(){ IP >An8+
return(p - 1) * num + 1; :!/}*B
} <Z&gAqj 2
BoXCc"q[
/** %*uqtw8
* @return Returns the results. uJWX7UGuz
*/ HGKm?'['
publicList<E> getResults(){ ;gc2vDMv
return results; i2*nYd`K
} /L~*FQQK>
Ne[O9D
7
public void setResults(List<E> results){ Q.fBuF
this.results = results; ^_oLhNoez2
} ;A C] *
Ue%0.G|<W
public String toString(){ lA1R$
StringBuilder buff = new StringBuilder 7HF\)cz2
KGJB.<Be
(); lz( 9pz
buff.append("{"); wEp/bR1=
buff.append("count:").append(count); nQ+{1 C
buff.append(",p:").append(p); MT*b+&1e
buff.append(",nump:").append(num); 48DsRy
buff.append(",results:").append k X-AC5]
k >MgrtJI
(results); H!A^ MI
buff.append("}"); Oe#k|
return buff.toString(); %9Ue`8
} hImCy9i}
6y0C
} :Cuae?O,
t_N
`e(V
g(`6cY[}