Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 78l);/E{v
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 o`YBz~2
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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 )Cy>'l*Og7
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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 1KZigeHXI
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分页支持类: D!.c??
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java代码: G_+/ e]P
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package com.javaeye.common.util; MT!Y!*-5
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import java.util.List; [/a
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publicclass PaginationSupport { KElEGW
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publicfinalstaticint PAGESIZE = 30; }+@!c%TCx~
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privateint pageSize = PAGESIZE; KKC%!Xy
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privateList items; 30vxOkS
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privateint totalCount; t=B1yvE"
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privateint[] indexes = newint[0]; |y^=(|eM
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privateint startIndex = 0; +zh\W9
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public PaginationSupport(List items, int ao)';[%9s
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totalCount){ SZH`-xb!+5
setPageSize(PAGESIZE); O50_qu33ju
setTotalCount(totalCount); }||u{[
setItems(items); LK DfV
setStartIndex(0); X):7#x@uy
} >ZJ]yhbhK
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public PaginationSupport(List items, int Nvd(?+c
w=#'8ZuU
totalCount, int startIndex){ 'LMj.#A<g
setPageSize(PAGESIZE); P")I)>Q6
setTotalCount(totalCount); vv.E6D^x(
setItems(items); sT;wHtU
setStartIndex(startIndex); G QYR`;>
} 0B(s+#s
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public PaginationSupport(List items, int 3O,nNt;L{
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totalCount, int pageSize, int startIndex){ IL|Q-e}Ol
setPageSize(pageSize); @eJ8wf]
setTotalCount(totalCount); {dZ]+2Z~+
setItems(items); U;W9`JT<.f
setStartIndex(startIndex); @<P2di
} t+a.,$U
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publicList getItems(){ 6FzB-],
return items; [2-n*a(q
} -)(5^OQ
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publicvoid setItems(List items){ TVcA%]y{;
this.items = items; ?#w} S%
} {.2\}7.c
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publicint getPageSize(){ X7!q/1$J
return pageSize; `,6|6.8#
} di/QJrw
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publicvoid setPageSize(int pageSize){ 4|K\pCw
this.pageSize = pageSize; U>lf-iI2B
} Dizz ?O
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publicint getTotalCount(){ 6C2~0b
return totalCount; |'z8>1
} WGz)-IB!PE
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publicvoid setTotalCount(int totalCount){ %rb$tKk
if(totalCount > 0){ "`ftcJUd
this.totalCount = totalCount; F6}RPk\=i
int count = totalCount / &Pb:P?I
p
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pageSize; U5kKT.M
if(totalCount % pageSize > 0) nsI+04[F
count++; \'Ae,q|w
indexes = newint[count]; vu0Ue
for(int i = 0; i < count; i++){ > T* `Y0P
indexes = pageSize * \Wfw\x0.
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i; Z$/76
} T)gulP
}else{ ?5EH/yV;
this.totalCount = 0; e%[*NX/
} *:yG)J 3F
} T^7Cv{[
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publicint[] getIndexes(){ ~uc7R/3ss
return indexes; K#+?oFo:
} 5Rl\& G\
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publicvoid setIndexes(int[] indexes){ v\,N"X(,
this.indexes = indexes; 1_TuA(
} esJ7#Gxt
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publicint getStartIndex(){ W+&5G(z~
return startIndex; m}'_Poc
} tle`O)&uo
}AS/^E
publicvoid setStartIndex(int startIndex){ U=bx30brh%
if(totalCount <= 0) 7,SQz6]
this.startIndex = 0; e>z"{ u(F0
elseif(startIndex >= totalCount) cR3d&/_,U
this.startIndex = indexes o^/
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[indexes.length - 1]; #`u}#(
elseif(startIndex < 0) ,Iyc0
this.startIndex = 0; 8vVE
else{ 1*8;)#%&
this.startIndex = indexes 4SI~y;c)
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[startIndex / pageSize]; a|FkU%sjzZ
} -US:a8`
} C{bxPILw
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publicint getNextIndex(){ kxhsDD$@p
int nextIndex = getStartIndex() + <;Hb7p3N
7z$Z=cs
pageSize; eS!]..%y
if(nextIndex >= totalCount) OV]xo8a;
return getStartIndex();
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else i]c{(gd`
return nextIndex; WhW}ZS'r
} <uuumi-!%G
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publicint getPreviousIndex(){ WRD
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int previousIndex = getStartIndex() - |Ml~Pmpp
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pageSize; W+i^tmj
if(previousIndex < 0) .h W>#
return0; %k#+nad
else @SD XJJh
return previousIndex; Rmw=~NP5
} H=BI%Z
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} ?1ey$SSU]
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抽象业务类 E,m|E]WP
java代码: @_C]5D^J^~
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/** Bb=r?;zjO
* Created on 2005-7-12 -
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*/ 7"Xy8]i{z
package com.javaeye.common.business; &MpLm&
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import java.io.Serializable; qefp3&ls
import java.util.List; oSrA4g
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import org.hibernate.Criteria; Xgx/ubca0
import org.hibernate.HibernateException; q(qm3OxYo
import org.hibernate.Session; W_wC"?A%
import org.hibernate.criterion.DetachedCriteria; us.[wp'Sh
import org.hibernate.criterion.Projections; p-"C^=l
import Wq3PN^
""7H;I&
org.springframework.orm.hibernate3.HibernateCallback; 1<vJuF^
import m^oG9&";
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org.springframework.orm.hibernate3.support.HibernateDaoS .h
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upport; 2@MpWj4
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import com.javaeye.common.util.PaginationSupport; M<Bo<,!ua
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public abstract class AbstractManager extends
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HibernateDaoSupport { #v(As)4^
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privateboolean cacheQueries = false; Ei:m@}g
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privateString queryCacheRegion; lai@,_<GV
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publicvoid setCacheQueries(boolean ~EmK;[Z
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cacheQueries){ 6/cm TT$i
this.cacheQueries = cacheQueries; }N9PV/a
} P6%qNR/ x
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publicvoid setQueryCacheRegion(String A@~9r9Uf
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queryCacheRegion){ b6S"&hs
this.queryCacheRegion = ;L:UYhDbUx
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queryCacheRegion; Gu{1%bb#kL
} "
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publicvoid save(finalObject entity){ $~q{MX&J
getHibernateTemplate().save(entity); *As"U99(
} @8\0@[]
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publicvoid persist(finalObject entity){ 9+(6/<
getHibernateTemplate().save(entity); B0RVtbK
} T=w0T-[f
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publicvoid update(finalObject entity){ rk%pA-P2
getHibernateTemplate().update(entity); 9/8+R%
} IHW s<U
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publicvoid delete(finalObject entity){ x%)oL:ue
getHibernateTemplate().delete(entity); wy|b Hkr_
} I5j|\ /Ht
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publicObject load(finalClass entity, Jm=3%H
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finalSerializable id){ S9*68l
return getHibernateTemplate().load 0{d)f1
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(entity, id); }x6)}sz7
} bfb9A+]3'
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publicObject get(finalClass entity, l^tRy_T:-
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finalSerializable id){ .,VLQbtg
return getHibernateTemplate().get Md9y:)P@Y
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(entity, id); "8)%XSb
} k N* I_#
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publicList findAll(finalClass entity){ 2ETv H~23
return getHibernateTemplate().find("from |pknaz
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" + entity.getName()); Yx66Xy
} ,y0 &E8Z
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publicList findByNamedQuery(finalString y'6l fThT
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namedQuery){ _^?_Vb
return getHibernateTemplate 3 %BI+1&T_
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().findByNamedQuery(namedQuery); lV./K;\T
} )`<&~>qp
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publicList findByNamedQuery(finalString query, lwG)&qyVd
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finalObject parameter){ N3Q
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return getHibernateTemplate r^E(GmW
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().findByNamedQuery(query, parameter); wKpD++k
} Ke[`zui@?
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publicList findByNamedQuery(finalString query, xqDz*V/mD
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finalObject[] parameters){ <h|&7
return getHibernateTemplate ]l=CiG4!M
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().findByNamedQuery(query, parameters); 71IM`eL=ED
} Om;`"5
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publicList find(finalString query){ #l* w=D?
return getHibernateTemplate().find !u:;Ew
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(query); %LqT>HXJ
} sA+K?_
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publicList find(finalString query, finalObject ;B }4pv}
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parameter){ 6\UIp#X
return getHibernateTemplate().find vXM{)
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(query, parameter); |<8Fa%!HHc
} YJDJj
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public PaginationSupport findPageByCriteria ;eW)&qzK
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(final DetachedCriteria detachedCriteria){ BNO+-ob-
return findPageByCriteria =RM]/O9
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); >~'z%
} lQRtsmZ0
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public PaginationSupport findPageByCriteria zTq"kxn'
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(final DetachedCriteria detachedCriteria, finalint 5]kv1nQ
nb*`GE
startIndex){ E2=vLI]
return findPageByCriteria y\:Ma7V
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(detachedCriteria, PaginationSupport.PAGESIZE, so Lmr's
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startIndex); kf95 )iLo
} #7YJ87<E
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public PaginationSupport findPageByCriteria @L 6)RF
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(final DetachedCriteria detachedCriteria, finalint `O%O[
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pageSize, LXth-j=]
finalint startIndex){ d<m.5ECC}
return(PaginationSupport) 3".#nN
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getHibernateTemplate().execute(new HibernateCallback(){ rzvKvGd#N
publicObject doInHibernate P*ZMbAf.
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(Session session)throws HibernateException { \0e`sOS`L
Criteria criteria = Vkf{dHjW
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detachedCriteria.getExecutableCriteria(session); }YM[aq?6
int totalCount = HHs!6`R$0c
Bf[`o<c
((Integer) criteria.setProjection(Projections.rowCount #D ]CuSi
rz%^l1@-
()).uniqueResult()).intValue(); 2^r J|Ni
criteria.setProjection eq<!
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(null); r'o378]=
List items = ;Z`R!
b0x%#trA{
criteria.setFirstResult(startIndex).setMaxResults 0fqycGSmU
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(pageSize).list(); V:+z 3)qF
PaginationSupport ps = 8NJT:6Q7l
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new PaginationSupport(items, totalCount, pageSize, $++O@C5
*!dA/sid
startIndex); 5;HCNwX
return ps; }EJ/H3<
} bUYjmb2g)
}, true); vWa\8y f
} !?|xeQ}
@Q;s[Kg{!
public List findAllByCriteria(final 0f'LXn
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DetachedCriteria detachedCriteria){ (I35i!F+tY
return(List) getHibernateTemplate y3PrLBTz
# nAq~@X
().execute(new HibernateCallback(){ uotW[L9
publicObject doInHibernate D`KaIqLz
h[<l2fy
(Session session)throws HibernateException { ' d?6 L
Criteria criteria = <num!@2D
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detachedCriteria.getExecutableCriteria(session); Tb8r+~HK
return criteria.list(); 8yH)9#>
} !DF5NAE
}, true); )%lPKp4]
} P|C5k5
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public int getCountByCriteria(final wTG(U3{3K
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DetachedCriteria detachedCriteria){ [8 H:5Ho
Integer count = (Integer) h@y>QhYU0
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getHibernateTemplate().execute(new HibernateCallback(){ pUW7p
publicObject doInHibernate 3=*ur( Qy
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(Session session)throws HibernateException {
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Criteria criteria = Ki&a"Fu3
@~UQU)-(
detachedCriteria.getExecutableCriteria(session); xH}bX- m
return k]`-Y E
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criteria.setProjection(Projections.rowCount {];-b0MS~
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()).uniqueResult(); l\uNh~\
} brlbJFZ19
}, true); =q`T|9v
return count.intValue(); jp^Sw|
} {Qn{w%!|
} !]RSG^%s{
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用户在web层构造查询条件detachedCriteria,和可选的 )S/=5Uc
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 #N'9
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PaginationSupport的实例ps。 ?,8+1"|$A]
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ps.getItems()得到已分页好的结果集 2A:h&t/|C
ps.getIndexes()得到分页索引的数组 `u PLyS.
ps.getTotalCount()得到总结果数 p8?v
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ps.getStartIndex()当前分页索引 Mw)6,O`
ps.getNextIndex()下一页索引 Y:, rN
ps.getPreviousIndex()上一页索引 3eXIo=
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 kxJ[Bi#
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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 2CneRKQy
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一下代码重构了。 { I\og
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我把原本我的做法也提供出来供大家讨论吧: 85;bJfY
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首先,为了实现分页查询,我封装了一个Page类: UxzF5V5
java代码: ~(kqq#=s
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/*Created on 2005-4-14*/ hqmE]hwc
package org.flyware.util.page; "J=Cy@SSa
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/** OE9,D:tv
* @author Joa $~W5! m
* GZNN2
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*/ }(|gC,
publicclass Page { ) ba~7A
Q}KOb4D
/** imply if the page has previous page */ *X2PT(e[
privateboolean hasPrePage; 0doJF@H
O=(F46 M
/** imply if the page has next page */ &ah%^Z4um
privateboolean hasNextPage; ]a4+] vLK
kP ,8[r
/** the number of every page */ ^-[
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privateint everyPage; J'$NBws
r9'[7b1l
/** the total page number */ /UK]lP^w]!
privateint totalPage; ^jwzCo-
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/** the number of current page */ 4n7Kz_!SVf
privateint currentPage; Zr2!}jD9a
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/** the begin index of the records by the current V<jj'dZfW
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query */ vk48&8
privateint beginIndex; PQ[?zNrSV
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/** The default constructor */ bS r"k
public Page(){ $5)#L$!,]
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} 9n{Y6I
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/** construct the page by everyPage
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* @param everyPage Td'(RV
* */ pTwzVz~
public Page(int everyPage){ GyN|beou
this.everyPage = everyPage; ~io. TS|r
} m{ !$_z8:
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/** The whole constructor */ sIgTSdk
public Page(boolean hasPrePage, boolean hasNextPage, 8TT#b?d
~44u_^a
oMj"l#a*
int everyPage, int totalPage, d4;$=P
int currentPage, int beginIndex){ LkS tU)
this.hasPrePage = hasPrePage; v7wyQx+Q
this.hasNextPage = hasNextPage; jc
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this.everyPage = everyPage; |xFA}
this.totalPage = totalPage; nsU7cLf"^V
this.currentPage = currentPage; aO&{.DO2
this.beginIndex = beginIndex; "I/05k K
}
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/** yj4"eDg]
* @return )-&@8`
* Returns the beginIndex. c-XO}\?
*/ *pa hZiO
publicint getBeginIndex(){ Uq#2~0n>
return beginIndex; Q!@M/@-Ky
} z@~H{glo
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/** JP<j4/
* @param beginIndex ]?@ [Ny=0
* The beginIndex to set. ="& GU%$
*/ !<:Cd(bM
publicvoid setBeginIndex(int beginIndex){ RxYENG]/6
this.beginIndex = beginIndex; IeYNTk&<
} p;}`PW
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/** uD=Kar
* @return Rh^@1{yr
* Returns the currentPage. M11\Di1
*/ HZRFE[ 9nb
publicint getCurrentPage(){ )Su>8f[?e
return currentPage; )y*&&q
} ZL<X*l2
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/**
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* @param currentPage %eDSo9Y
* The currentPage to set. 7gf(5p5ZV
*/ 'fU #v`i
publicvoid setCurrentPage(int currentPage){ &!X<F,
this.currentPage = currentPage; TF:'6#p
} {TNORbZz
Ip{R'HG/
/** piM4grg
\
* @return .>R`#@+I
* Returns the everyPage. IsI5c
*/ jSE)&K4nI
publicint getEveryPage(){ z)C/U
return everyPage; i&>^"_4rc
} G]rY1f0
pV ^+X}
/** }qECpKa0
* @param everyPage zBy} > Jx
* The everyPage to set. JyE-c}I
*/ g]vB\5uA:
publicvoid setEveryPage(int everyPage){ n/1t UF
this.everyPage = everyPage; #9|&;C5',!
} Qpmq@iL
c%pf,sm'
/**
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* @return m*_X PY
* Returns the hasNextPage. "ZGP,=?y2
*/ Li5&^RAo|J
publicboolean getHasNextPage(){ WBWW7 HK
return hasNextPage; no<$=(11i
} n5d8^c! 2
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/** Mn
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* @param hasNextPage 3XQa%|N(
* The hasNextPage to set. PSq?8.
*/ LhLAQ2~
publicvoid setHasNextPage(boolean hasNextPage){ #b;?:.m\=
this.hasNextPage = hasNextPage; y`n?f|nf
} %J-0%-/_S:
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/** gf8o~vKX$G
* @return uluAqDz`
* Returns the hasPrePage. ]4H)GWHKg
*/ `qhT
publicboolean getHasPrePage(){ I zTJ7E*i
return hasPrePage; rlKR
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} aDRcVA$*
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/** }
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* @param hasPrePage e&
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* The hasPrePage to set. 6m?<"y8]
*/ !lfE7|\p
publicvoid setHasPrePage(boolean hasPrePage){ iG54 +]
this.hasPrePage = hasPrePage; Qg/FFn^Kg*
} M6p\QKi
s_y8+BJaV
/** l3Zi]`@r
* @return Returns the totalPage. ;iiCay37F
* ;EJ!I+
*/ >rQj1D)@
publicint getTotalPage(){ 9o>D
Uc
return totalPage; %mmV#vwp
} ]?(kaNQ"D
8B*(P>
/** P{A})t7
* @param totalPage PI*@.kqR-
* The totalPage to set. ];w}?LFb
*/ *S*49Hq7c
publicvoid setTotalPage(int totalPage){ x,mt}>
this.totalPage = totalPage; iz-z?)%
} ^(:~8 h
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} hdw.S`~}%
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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 wIi(\]Q
"B:FSWM_-
个PageUtil,负责对Page对象进行构造: p[P#!
java代码: 1?&|V1vc
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Chnt)N`/B4
/*Created on 2005-4-14*/ @Pcgm"H<
package org.flyware.util.page; 1J9p1_d5
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import org.apache.commons.logging.Log; K/*R}X
import org.apache.commons.logging.LogFactory; z"mVE T
yP3I^>AZ3
/** ;l!<A
* @author Joa zp8x/,gwF
* }o:LwxNO
*/ \Ki3ls
publicclass PageUtil {
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wuXQa
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privatestaticfinal Log logger = LogFactory.getLog q<3La(^/
`l]Lvk8O
(PageUtil.class); $!wU[/k
^|Z'}p|&
/** RI8*'~ix]
* Use the origin page to create a new page o;6~pw%
* @param page QP\:wi
* @param totalRecords h.R46 :
* @return 4eB'mPor
*/ 4)e1K/PJ)
publicstatic Page createPage(Page page, int 2+y wy^
}i^M<A O
totalRecords){ c!\T0XtT
return createPage(page.getEveryPage(), BGi'UL,
-KC@M
page.getCurrentPage(), totalRecords); nZi&`HjQ
} Zocuc"j
J\+fkN<.
/** ;O)*!yA(GG
* the basic page utils not including exception yL
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>8{w0hh;
handler xKE=$SV(
* @param everyPage ;!f~
* @param currentPage c&bhb[
* @param totalRecords *-=/"m
* @return page *
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*/ Io<T'K
publicstatic Page createPage(int everyPage, int e~
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currentPage, int totalRecords){ 8B-PsS|'
everyPage = getEveryPage(everyPage); Vf:.C|Z
currentPage = getCurrentPage(currentPage); ffk>IOH
int beginIndex = getBeginIndex(everyPage, j_,/U^Ws|f
I*%3E.Z@g
currentPage); .$peq
int totalPage = getTotalPage(everyPage, %Y0lMNP
M{orw;1Isy
totalRecords); CRCy)AS,t
boolean hasNextPage = hasNextPage(currentPage, Vp; `!+z"
8 !:2:
totalPage); [ p,]/ ^ N
boolean hasPrePage = hasPrePage(currentPage); 9j^rFG!n
#m{(aa9;
returnnew Page(hasPrePage, hasNextPage, ^`#7(S)a/
everyPage, totalPage, &iu]M=Yb
currentPage, e=h-}XRC
T\Xf0|y
beginIndex); FWeUZI+
} 7l-MVn_8
MzB.Vvsy%9
privatestaticint getEveryPage(int everyPage){ #@-dT,t
return everyPage == 0 ? 10 : everyPage; r{?qvl!q
} BYdGK@ouk
KW'nW
privatestaticint getCurrentPage(int currentPage){ D8!
Y0
return currentPage == 0 ? 1 : currentPage; R%r25_8
} v(Kj6 '
M^\`~{*T
privatestaticint getBeginIndex(int everyPage, int Q1*_l
~rI2 RJ
currentPage){ i{N?Y0YQs0
return(currentPage - 1) * everyPage; ;yqHt!N
} ]6^S:K_"
2?LPr
privatestaticint getTotalPage(int everyPage, int shdzkET8N
/Bgqf,N |
totalRecords){
}BW&1*M{
int totalPage = 0; S=S/]]e
o_=4Ex
"
if(totalRecords % everyPage == 0) ye(av&Hn
totalPage = totalRecords / everyPage; z2Wblh"_
else lGK7XAx,
totalPage = totalRecords / everyPage + 1 ; unFm~rcf
,
0X J|#%
return totalPage; m["e7>9G
} *GYLj[
o3Yb2Nw
privatestaticboolean hasPrePage(int currentPage){ _~tF2`,Y_p
return currentPage == 1 ? false : true; kz}Bc
F
} X!6dg.n5
}LS.bQKqi,
privatestaticboolean hasNextPage(int currentPage, V%;dTCq
9G6ZKqum
int totalPage){ e/x 9@1s#
return currentPage == totalPage || totalPage == J"h2"$v,
~C>;0a;<:
0 ? false : true; S['%>
} <]z4;~/&
4gEw}WiP
*!%n`BR '
} ,hJx3g5#n
~x4]p|)</
wPYeKOh'
6)=;cc{Vr
IDF0nx]
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。 90F.9rh
=n=!s{A: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 ^h=gaNL
r91i :
做法如下: 3NZK$d=4
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 8z|]{XW{
r$M<vo6C
的信息,和一个结果集List: I4ZbMnO
java代码: Nk%$;Si
]!1HN3
`'r~3kP*NT
/*Created on 2005-6-13*/ ;[Xf@xf
package com.adt.bo; -sf[o"T,j
KCbOO8cQS
import java.util.List; L{;Q6_m
W:j9 KhvT
import org.flyware.util.page.Page; h(~of(
2YQBw,gG
/** xrY >Or
* @author Joa dR>$vbjh1Z
*/ U4Y)Jk
publicclass Result { X-bM`7'H
o,_F;ZhE
private Page page; 45Zh8 k
9T$%^H9
private List content; >D##94PZ
afaQb
/** {#@[ttw$U
* The default constructor |V}tTx1
*/ .2rpQa/h
public Result(){ pnuwjU-
super(); zcOm"-E-
} T8*;?j*@
D'D IC
/** OFcP4hDi
* The constructor using fields 3*7 klu
* 2Z"\%ZD
* @param page [*C~BM
* @param content kDR5kDiS
*/ k $ SMQ6
public Result(Page page, List content){ 0[uOKFgE
this.page = page; 6&LmR75C
this.content = content; 7FaF]G
} /{[tU-}qJ
F$|d#ny
/** FL$S_JAw
* @return Returns the content. 8/P!i2o
*/ 8U]mr+
publicList getContent(){ 6>&(OV
return content; FSkX95
} OYa9f[ $
\|]+sQ WQ
/** 7;6'=0(
* @return Returns the page. g^=Ruh+
*/ 0,#n_"
public Page getPage(){ AEFd,;GF
return page; oj?y_0}:^
} |Zo36@s
I&^hG\D
/** ]gA2.,)}D
* @param content hv|-`}#0
* The content to set. @L607[!?
*/ mZ?QtyljT
public void setContent(List content){ /
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this.content = content; ]}&HvrOld
} Nd;pkssd
jQfnc:'
/** CqX*.j{
* @param page ;kG"m7-/
* The page to set. HYJEz2RF
*/ p~(STHDe#
publicvoid setPage(Page page){ MQ'=qR
this.page = page; N
/;Vg^Wx
} c4Q%MRR
} 1p-<F3;
rof9Rxxe-
kcNPdc
#z*,-EV|
k
$# ,^)T
2. 编写业务逻辑接口,并实现它(UserManager, 02:`Joy2D
Xoq -
UserManagerImpl) `Xi)';p
java代码: !"F8jA}
T$DFTr\\
*u[@C
/*Created on 2005-7-15*/ NUuIhB+
package com.adt.service; }4,[oD
g\49[U}[~F
import net.sf.hibernate.HibernateException; +t]Ge
>S
hfvC-f97L
import org.flyware.util.page.Page; l['ER$(7
?cK67|%W
import com.adt.bo.Result; k$Ug;`v#
^>fr+3a"P
/** tI.ho
* @author Joa yZmeke)_
*/ K'K/}q<
publicinterface UserManager { dD
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public Result listUser(Page page)throws A=D
G+z''
*~UK5Brf1
HibernateException; '+GYw$
16~5 ;u
} + =U9<8
d]?fL&jr
3CSwcD
$/E{3aT@F2
zP$"6~.
java代码: {3Dm/u%=9|
+.u
HY`A
530Kk<%^}8
/*Created on 2005-7-15*/ -(#`JT8
package com.adt.service.impl; 9S5C{~P4
sei%QE]!/
import java.util.List; H.tfn>N|
gU@R
import net.sf.hibernate.HibernateException; nbDjoZZ4
sv!6zJs
import org.flyware.util.page.Page; #)%X0%9.*<
import org.flyware.util.page.PageUtil; :vFYqoCn
7e)j|a-!<
import com.adt.bo.Result; 1b2xWzpG
import com.adt.dao.UserDAO; MJn=
import com.adt.exception.ObjectNotFoundException; a{.-qp
import com.adt.service.UserManager; , LqfwA|
7?uIl9Vk>(
/** w)>/fG|;
* @author Joa
"'Q~&B;@
*/ LS<*5HWX
publicclass UserManagerImpl implements UserManager { Zo Ra^o
8;3I:z&muQ
private UserDAO userDAO; @A-E
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/** QC1\Sn /
* @param userDAO The userDAO to set. YgQb(umK
*/ TO/SiOd
publicvoid setUserDAO(UserDAO userDAO){ aL8Z|*
this.userDAO = userDAO; ;"NW=P&
} \.=,}sV2Z
w6AG:u
/* (non-Javadoc) V'l9fj*E
* @see com.adt.service.UserManager#listUser Rvj[Csgi
LiEDTXRz
(org.flyware.util.page.Page) #0Z%4W Q
*/ {w v{"*Q9Q
public Result listUser(Page page)throws aM\Ph&c7e'
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HibernateException, ObjectNotFoundException { jZ<f-Ff0
int totalRecords = userDAO.getUserCount(); -]:1zU
if(totalRecords == 0) c:-n0m'i
throw new ObjectNotFoundException ca'c5*Fs
EB
p(^rj
("userNotExist"); H<l0]-S{
page = PageUtil.createPage(page, totalRecords); K6nNrd}p:
List users = userDAO.getUserByPage(page); kM76?M
returnnew Result(page, users); =BeJ.8$@VC
} sGGi7%
8y]{I^z}
} ca:Vdrw`
n?v$C:jLN
k.%FGn'fR
~AcjB(
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其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 @:P:`Zk
yY80E[v
询,接下来编写UserDAO的代码: V"A*B
3. UserDAO 和 UserDAOImpl: 2'}/aL|G
java代码: `OWwqLoeA
/)V8X#,
#D%l;Ae
/*Created on 2005-7-15*/ Shu=oweJ
package com.adt.dao; t28 y=nv
U)_x(B3d/
import java.util.List; }t1J`+x%
jjg[v""3|
import org.flyware.util.page.Page; PC& (1kJ
(_Rl
f$D
import net.sf.hibernate.HibernateException;
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/** 1sXVuto
* @author Joa Ne}x(uRn
*/ \WM"VT
publicinterface UserDAO extends BaseDAO { E~`<n]{G-C
O/fm/
publicList getUserByName(String name)throws 0G8zFe*p
Yo,n#<37
HibernateException; F?4&qbdD
f}Uf*Bp
publicint getUserCount()throws HibernateException; _[y<u})
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f}~
publicList getUserByPage(Page page)throws ,BlNj^5f
1j!{?t?
HibernateException; 8/W2;>?wKc
B{7hRk.5!
} 8LGNV&Edg
:Mq{ES%
?rQIUP{D7
g 4lk
OsgjSJrf
java代码: gO_d!x*
Pq3|O
Z
KH9D},
/*Created on 2005-7-15*/ DP!~WkU~
package com.adt.dao.impl; ,xy$h }g
Jmun^Q/h
import java.util.List; lT;uL~j
=dY!-#yg!
import org.flyware.util.page.Page; Z
\;{e'#o
B5!|L)7>{p
import net.sf.hibernate.HibernateException; "?s
import net.sf.hibernate.Query; ?GeMD
/]
'~AR|8q?
import com.adt.dao.UserDAO; Z4D[nPm$
|) CfO 4
/** ed$w5dv
* @author Joa x\K,@
*/ ^NFL3v8
public class UserDAOImpl extends BaseDAOHibernateImpl H~lvUHN
M[7$F&&n
implements UserDAO { \W"p<oo|H
uS5ADh
/* (non-Javadoc) k6(0:/C
* @see com.adt.dao.UserDAO#getUserByName b}Xh|0`b+
$[+)N~
(java.lang.String) p4z
thdN[
*/ Up\ k67
publicList getUserByName(String name)throws >yqFO
B$_-1^L
e
HibernateException { yG,uD!N]|
String querySentence = "FROM user in class 6-f-/$B
[s~6,wz
com.adt.po.User WHERE user.name=:name"; a[NR%Xq
Query query = getSession().createQuery E[c6*I
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(querySentence); c2fw;)j&X
query.setParameter("name", name); &L r~x#Wx
return query.list(); .FA99|:
} F+<Z%KuCu
-BEd7@?A
/* (non-Javadoc) q;QE(}.g
* @see com.adt.dao.UserDAO#getUserCount() o8N,mGj}
*/ cs*"9nKl
publicint getUserCount()throws HibernateException { !twYjOryH[
int count = 0; ev1:0P
String querySentence = "SELECT count(*) FROM u4DrZ-v
}z-6 ,i)'k
user in class com.adt.po.User";
wnHfjF
Query query = getSession().createQuery DJ|lel/'
LU+}iA)
(querySentence); YhL^kM@c
count = ((Integer)query.iterate().next deCi\n
Qn)AS1pL+
()).intValue(); u0nIr9
return count; 2Wr^#PY60
} 5'n$aFqI
M# cJ&+rP
/* (non-Javadoc) +nL#c{
* @see com.adt.dao.UserDAO#getUserByPage XUTsW,WC
gB]jLe
(org.flyware.util.page.Page) T%w5%{dqJ
*/ [R<>3}50Y
publicList getUserByPage(Page page)throws OuyO_DSI
S%jFH4#
HibernateException { qD,/Qu62
String querySentence = "FROM user in class a7jE*%f9
Uz%2{HB@{
com.adt.po.User"; <aY>fg d/1
Query query = getSession().createQuery {TaYkuWS
ff
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(querySentence); ;Swy5z0=ro
query.setFirstResult(page.getBeginIndex()) ;KT/;I
.setMaxResults(page.getEveryPage()); H/ar:j
return query.list(); I/go$@E"
} I?_WV_T&
XC4wm#R
} g9j&\+h^
m|Sf'5fK
q2*1Gn9!j
vPAL,
]U,m
1
至此,一个完整的分页程序完成。前台的只需要调用 Wu'9ouw!
cJzkA^T9
userManager.listUser(page)即可得到一个Page对象和结果集对象 S{N=9934_
y:Aha#<
的综合体,而传入的参数page对象则可以由前台传入,如果用 W#\{[o
u@t~*E5BpM
webwork,甚至可以直接在配置文件中指定。 uobQS!
FSYs1Li_C
下面给出一个webwork调用示例: M9?f`9
java代码: ZtY?X- 4_
0{-?Wy
~/rKKc
/*Created on 2005-6-17*/ &ju.5v|
package com.adt.action.user; v
,zD52
_%(.OR
import java.util.List; k}!'@
S" (Nf+ux
import org.apache.commons.logging.Log; O)D$UG\<
import org.apache.commons.logging.LogFactory; gyxC)br
import org.flyware.util.page.Page; uw(Ml=
H'Jz:6
import com.adt.bo.Result; Y++n0sK5<
import com.adt.service.UserService; $GYy[8{:V
import com.opensymphony.xwork.Action; cUn>gT
HhwAzk/G~
/** bmJdZD7-<k
* @author Joa \{v-Xe&d^
*/ H~bbkql
publicclass ListUser implementsAction{ V=8npz
wLNkXC
privatestaticfinal Log logger = LogFactory.getLog #Y'ewu;qJ
zR)/h
(ListUser.class); pl/ek0QX
NDJP`FI
private UserService userService; ^
4*#QtO
zx@L sp
private Page page; N?O^"
4vV\vXT *
privateList users; zL9:e7o
Wl}J=
/* #/HZ[Vw
* (non-Javadoc) 4/OmgBo'
* @U@O#+d'ZR
* @see com.opensymphony.xwork.Action#execute() a'r1or4
*/ v#e*RI2}
publicString execute()throwsException{ 00@F?|-j
Result result = userService.listUser(page); `qRyh}Ax"
page = result.getPage(); >=;hnLu
users = result.getContent(); 7spZe"
return SUCCESS; @!^Y_q
} A(H2Gt
D
'S*]JZ1
/** 1DGl[k/zv
* @return Returns the page. !Y&]Y
G
*/ _&S;*?K.
public Page getPage(){ P)LOAe1'
return page; VF g(:
} QL*RzFAD3
CeM%?fr5
/** n )\(\V7
* @return Returns the users. HZ1 nuA
*/ t<`d*M2w
publicList getUsers(){ <p-@XzyE
return users; .1z=VLKF'
} &WOm[]Q4
FR>[g`1
/** sL;;'S&
* @param page zKp R:F
* The page to set. ? cn`N|
*/ piqh7u3~
publicvoid setPage(Page page){ yXqC
this.page = page; H )CoByaj
} Yq4nmr4
z, FPhbFn
/**
HLQ>
|,9
* @param users I!SIy&=W
* The users to set. #2"'tHf4
*/ @!}/$[hu1
publicvoid setUsers(List users){ 0d1!Q!PH3
this.users = users; 1_l)$"
} /a)^)
@Ae&1O;Zh
/** !6a;/ys
* @param userService $s-B
* The userService to set. @(+\*]?^&
*/ Ro4!y:2|
publicvoid setUserService(UserService userService){
V<?0(esgR
this.userService = userService; ]7oo`KcQ|
} kD7'BP/#
} Y88N*axDW.
*'tGi_2?(
|o*qZ}6
f2&6NC;
o6:bmKWE
上面的代码似乎看不出什么地方设置了page的相关初值,事实上, 2.]d~\
RLzqpE<rJ
可以通过配置文件来进行配置,例如,我想每页显示10条记录,那 s^4wn:*$zd
f.bw A x
么只需要: 9U4[o<G]=
java代码: XBB>"
uH,/S4?X
+$#XV@@~
<?xml version="1.0"?> Zsmv{p
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork j}`ku9S~
eu~ u-}.
1.0//EN" "http://www.opensymphony.com/xwork/xwork- :RwURv+kT
w4_Xby)
1.0.dtd"> "5'eiYms
j>l
<xwork> %4t?X
<:T/hm$
<package name="user" extends="webwork- F! Cn'*
BE],PCpPr
interceptors"> aQf2}kD
!%DE(E*'(
<!-- The default interceptor stack name !&3"($-U3G
^)a:DKL
--> R y(<6u0
<default-interceptor-ref )s4:&!
9_.pLLx
name="myDefaultWebStack"/> 3gD <!WI
w=: c7Y+
<action name="listUser" @ &rf?:
j]`hy"
class="com.adt.action.user.ListUser"> a=x&sz\x
<param PRx- 0S
zAvI f
name="page.everyPage">10</param> FP7N^HVBG=
<result dm40qj
-o~n06p
name="success">/user/user_list.jsp</result> #$L/pRC
</action> 6ecx!uc$
Da!vGr
</package> ;l<Hen*
X+<9-]=
</xwork> {7MY*&P$,
>Q ^ mR
JUXBMYFus
Y C<FKWc
2V$Jn8v,`{
.6y*Z+Zg
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 9C{Xpu
I9rQX9#B
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。 g
4|ai*^
yx6^ mis4
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 ;-l^X%r
Ov4 [gHy&
E[=&6T4
w@O)b-b|w
e=IbEm{|
我写的一个用于分页的类,用了泛型了,hoho
fCnwDT
TDy)A2Z
java代码: w)1SZ}
ZCb@!V}=
| z_av
package com.intokr.util; H@ty'z?
.x/H2r'1
import java.util.List; GukwN]*OY
$Fy~xMA8O
/** pU,\ &3N
* 用于分页的类<br> h.Sbds
* 可以用于传递查询的结果也可以用于传送查询的参数<br> xB?!nd
* NwQ$gDgu t
* @version 0.01 u`oJ3mS;
* @author cheng xG Y!r"[
*/ M195[]
public class Paginator<E> { wdV)M?
privateint count = 0; // 总记录数 uH7rt
privateint p = 1; // 页编号 : 0Y.${h
privateint num = 20; // 每页的记录数 &hi][Pt
privateList<E> results = null; // 结果 ^L
Xr4
6z/&j} (
/** `/wXx5n5<
* 结果总数 A)d0Z6G`
*/ 5GPAt
publicint getCount(){ |Xd&aQ
return count; 9o6qN1A0g
} XRyeEwA;pp
~)X;z"y%b
publicvoid setCount(int count){ %?qzP'
this.count = count; *tkf)[(
} 99]s/KD2yb
/BF7N3
/** 4j i#Q
* 本结果所在的页码,从1开始 2"P1I
* ?V_v=X%w
* @return Returns the pageNo. $[J\sokpY
*/ d)XT> &
publicint getP(){ KK-+vq
return p; <8Z%'C6d
} akHQ&+[j
/8hjs{(;
/** ?o/p}6
* if(p<=0) p=1 gq~`!tW'
* kjQI=:i=
* @param p wJvk
*/ 09G]t1!,
publicvoid setP(int p){ &qa16bz
if(p <= 0) 40-/t*2Ly
p = 1; @OHNz!Lj:d
this.p = p; q zo)\,
} (.{. "
SxC(:k2b;
/** wc~ 9zh
* 每页记录数量 fKua om9
*/ (ueH@A"9;
publicint getNum(){ }2Im?Q
return num; (KfdN'vW
} +,D82V7S
AJzm/,H
/** R~N%sn
* if(num<1) num=1 (ijO|%?
*/ &N%-.&t'
publicvoid setNum(int num){ )oS~ish
if(num < 1) )%!X,
num = 1; dQ<e}wtg
this.num = num; kQ)2DCbdn
} ~i}/
Z@Qf0
c
/** ]7h;MR
* 获得总页数 xlW>3'uHfa
*/ FOcDBCrOe
publicint getPageNum(){ 0XL[4[LdA
return(count - 1) / num + 1; |:SXN4';?
} _b=})**
*I9G"R8
/** a1weTn*
* 获得本页的开始编号,为 (p-1)*num+1 %g4)f9>
*/ D[Ld=e8t
publicint getStart(){ `R$bx 64
return(p - 1) * num + 1; .+^o {b
} ACgWT
L+)mZb&
/** "xD5>(|^+Q
* @return Returns the results. :!,.c$M
*/ ['0^gN$:e
publicList<E> getResults(){ %5(v'/dQ
return results; +OUM 4y
} WxF@'kdn*,
6AmFl<
public void setResults(List<E> results){ 1+Y;
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this.results = results; GuJIN"P]
} xtp55"g
+T7FG_
public String toString(){ ra\|c>[%
StringBuilder buff = new StringBuilder 6K9-n}z
UAdj[m61
(); +Nka,C^O"
buff.append("{"); "S&1J8D|
buff.append("count:").append(count); j;*=
^s
buff.append(",p:").append(p); Y+~>9-S
buff.append(",nump:").append(num); ]}AyDy6C
buff.append(",results:").append ^#2Y4[@
P99s
(results); {|@N~c+
buff.append("}"); ve=
nh]N
return buff.toString(); 5{8,+
Z
} W{;LI
WsZ
]^l-k@
} XpOQBXbt
N;e*eMFE
%!)Dk<