Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 ZL!5dT&@W
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 Jl6biJx
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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 Ve"M8-{oKk
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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 ]nxSVKE4p
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分页支持类: {t'SA]|g
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java代码: JkLpoe81
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package com.javaeye.common.util; +rrA>~
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import java.util.List; [NGq$5
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publicclass PaginationSupport { NPE 4@c_a@
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publicfinalstaticint PAGESIZE = 30; RM25]hx
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privateint pageSize = PAGESIZE; ;Q5o38(
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privateList items; _(@Vf=t
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privateint totalCount; xWWVU}fd1
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privateint[] indexes = newint[0]; ronZa0
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privateint startIndex = 0; ?*QL;[n1
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public PaginationSupport(List items, int IJZx$8&A
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totalCount){ d=HD!
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setPageSize(PAGESIZE); Y1DbBDk
setTotalCount(totalCount); B|AIl+y
setItems(items); -BrJ5]T>*
setStartIndex(0); ?IiFFfs
} A;;OGJ,!\
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public PaginationSupport(List items, int 2.a{,d
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totalCount, int startIndex){ a{}8030S
setPageSize(PAGESIZE); BL\H@D
setTotalCount(totalCount); QA~Lm
setItems(items); wI[J> 9Qn
setStartIndex(startIndex); z Hl+P*)
} Oj7).U0;#
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public PaginationSupport(List items, int A{Y/eG8
# *7ImEN
totalCount, int pageSize, int startIndex){ y(**F8>?xE
setPageSize(pageSize); xUB{{8B:L
setTotalCount(totalCount); \%#luk@:
setItems(items); Oh7wyQiV
setStartIndex(startIndex); Gfle"_4m8
} .7Itbp6=R
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publicList getItems(){ 6s:
return items; q:,ck@-4
} P`n"E8"ab<
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publicvoid setItems(List items){ TI^X gl~
this.items = items; S"Ag7i
} n1y*`5!
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publicint getPageSize(){ @l~MY*hp
return pageSize; ((fFe8Rn)q
} C7MCMM|S
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publicvoid setPageSize(int pageSize){ MBFn s/
this.pageSize = pageSize; }Szs9-Wns
} tHH @[E+h
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publicint getTotalCount(){ tj" EUqKQ
return totalCount; arn7<w0
} o{MmW~/o&
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publicvoid setTotalCount(int totalCount){ 9E
if(totalCount > 0){ |
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this.totalCount = totalCount; 8ao>]5Rs3
int count = totalCount / ztaSIMZ
^ Mq8jw(2
pageSize; -lI6!a^
if(totalCount % pageSize > 0) $w! v
count++; t&(\A,ch%
indexes = newint[count]; N6/;p]|
for(int i = 0; i < count; i++){ N8`q.;qewz
indexes = pageSize * 0F[+rh"x
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i; )s8{|) -
} FzQ6UO~'
}else{ Z}r9jM
this.totalCount = 0; 9Ui|8e~=
} .:TSdusr~
} x/?w1
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publicint[] getIndexes(){ I- WR6s=
return indexes; x1 1ug
} W&9X <c*
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publicvoid setIndexes(int[] indexes){ 20BU;D3
this.indexes = indexes; ap .L=vn
} BGL-lJrG
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publicint getStartIndex(){ Jgzg[6
return startIndex; h1Q rFPQnu
} }LdeU:E4
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publicvoid setStartIndex(int startIndex){ ne'Y {n(8%
if(totalCount <= 0) Jnq}SUev
this.startIndex = 0; 2~W8tv0^b2
elseif(startIndex >= totalCount) |F?/L>
this.startIndex = indexes `&o>7a;
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[indexes.length - 1]; )gKX+'
elseif(startIndex < 0) A!aki}aT~
this.startIndex = 0; Vg8c}>7
else{ kntn9G
this.startIndex = indexes _{0IX
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[startIndex / pageSize]; 7!#34ue
} Y-:dPc{
} v\Xyz
)
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publicint getNextIndex(){ #w]@yL]|is
int nextIndex = getStartIndex() + +Uf+`
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pageSize; ~#9(Q
if(nextIndex >= totalCount) !l#n.Fx&3
return getStartIndex(); 6^hCW`jG
else ,Q>wcE6v
return nextIndex; fdzaM&
} 1<&nHFJ;[
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publicint getPreviousIndex(){ 0^zp*u
int previousIndex = getStartIndex() - Iq:
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pageSize; kZH IzU
if(previousIndex < 0) Nmu=p~f}3`
return0; vS+E`[
else tJZ3P@ L
return previousIndex; g7<u eF
} 3v:c'R0
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} 5SwQ9#
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抽象业务类 $Rv(v%
java代码: y,vrMWDy
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/** jL9to6 Hmr
* Created on 2005-7-12 2W vf[2Xw
*/ >r5s>A[YC
package com.javaeye.common.business; 2f7]=snCG
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import java.io.Serializable; \tZZn~ex
import java.util.List; E|hW{ oX3
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import org.hibernate.Criteria; gC\^"m
import org.hibernate.HibernateException; h(3ko
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import org.hibernate.Session; Y@R9+7!
import org.hibernate.criterion.DetachedCriteria; ,lr\XhO
import org.hibernate.criterion.Projections; EZg$mp1
import b0!ZA/YC-
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org.springframework.orm.hibernate3.HibernateCallback; CWS&f
g%o{
import ca!DZ%y
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org.springframework.orm.hibernate3.support.HibernateDaoS )MU)'1jc,
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upport; >.f'_2#Z&
v* /}s :a
import com.javaeye.common.util.PaginationSupport; `%A>{ A"
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public abstract class AbstractManager extends ^h\Y.
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HibernateDaoSupport { 23~KzC
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privateboolean cacheQueries = false; x4nmDEpa
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privateString queryCacheRegion; ^Y-
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publicvoid setCacheQueries(boolean JN:EcVuy
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cacheQueries){ S67>yqha
this.cacheQueries = cacheQueries; 3pk `&'
} /5 6sPl
7}
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publicvoid setQueryCacheRegion(String ]\Q9j7}37+
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queryCacheRegion){ Or*e$uMIY
this.queryCacheRegion = i*-L_!cc:
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queryCacheRegion; >lIQM3
} E{B=%ZNnm
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publicvoid save(finalObject entity){ >,s.!vpK
getHibernateTemplate().save(entity); ;^Hg\a
} b Q6<R4
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publicvoid persist(finalObject entity){ WyDL ah^/
getHibernateTemplate().save(entity); Dhy@!EOS
} vgvJ6$#
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publicvoid update(finalObject entity){ xD3Y-d9
getHibernateTemplate().update(entity); H|i39XV
} !Al?B9KJ
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publicvoid delete(finalObject entity){ .S=^)
getHibernateTemplate().delete(entity); qe"t0w|U?
} 7G<v<&
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publicObject load(finalClass entity, "ZU CYYre
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finalSerializable id){ R#0Z
return getHibernateTemplate().load b9gezXAcd
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(entity, id); ^~Dmb2h
} 5$w`m3>i(
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publicObject get(finalClass entity, NHjZ`=Js
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finalSerializable id){ 7xr@$-U
return getHibernateTemplate().get w;Jby
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(entity, id); ~xSAR;8
} ollk {N
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publicList findAll(finalClass entity){ A:-r2;xB
return getHibernateTemplate().find("from quEP"
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" + entity.getName()); C_~hX G
} X|iWnz+^
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publicList findByNamedQuery(finalString 9;*-y$@
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namedQuery){ ;5(ptXX1W
return getHibernateTemplate 8vL2<VT;
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().findByNamedQuery(namedQuery); SlRQi:
} D#I^;Xg0h
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publicList findByNamedQuery(finalString query, 9< $n'g
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finalObject parameter){ 71GyMtX
return getHibernateTemplate @ppT;9<d
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().findByNamedQuery(query, parameter); '!wI8f
} l#;DO9
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publicList findByNamedQuery(finalString query, >.)m|,
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finalObject[] parameters){ ][IEzeI_LN
return getHibernateTemplate )* \N[zm
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().findByNamedQuery(query, parameters); ZWH9E.uj
} Jiv%Opo/|
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publicList find(finalString query){ 'zg; *)x1/
return getHibernateTemplate().find wcI?.
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(query); i:coNK)4
} ` ,O#r0m
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publicList find(finalString query, finalObject %gb4(~E+N
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parameter){ z9B""ws
return getHibernateTemplate().find bkvm-$/
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(query, parameter); (&)PlIi7
} 8wXnc%
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public PaginationSupport findPageByCriteria g]V_)}
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(final DetachedCriteria detachedCriteria){ @*VfG CQ(
return findPageByCriteria Z@G[\"
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); @g{FNXY$ m
} mz'r<v2Tc
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public PaginationSupport findPageByCriteria %]m/fo4b
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(final DetachedCriteria detachedCriteria, finalint z{N~AaY
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startIndex){ m/T3Um
return findPageByCriteria P~H?[
;
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(detachedCriteria, PaginationSupport.PAGESIZE, nbMxQODk
;
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startIndex); hN5?u:
} m 3Y@p$i5
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public PaginationSupport findPageByCriteria t6+c"=P#
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(final DetachedCriteria detachedCriteria, finalint !pqfx93R*
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pageSize, 1[g -f,
finalint startIndex){ @ gv^
return(PaginationSupport) u3B[1Ae:K
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getHibernateTemplate().execute(new HibernateCallback(){ UBm L:Qv
publicObject doInHibernate o^!_S5zKe.
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(Session session)throws HibernateException { Jx jP'8
Criteria criteria = +~x'1*A_
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detachedCriteria.getExecutableCriteria(session); A%[BCY_
int totalCount = s.#%hPX{
|}-bMQ|
((Integer) criteria.setProjection(Projections.rowCount .yF@Ow
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()).uniqueResult()).intValue(); 0'3f^Ajf
criteria.setProjection &&daQg4Ha
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(null); +}.~"
List items = vR)f'+_Nz
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criteria.setFirstResult(startIndex).setMaxResults jv4O
QH d^?H*
(pageSize).list(); F+m%PVW:
PaginationSupport ps = 2YbI."ob
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new PaginationSupport(items, totalCount, pageSize, "?X,);5S
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startIndex); X9-WU\?UC
return ps;
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} %tvP\(]h
}, true); cS2PrsUx
} W0 n?S
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public List findAllByCriteria(final )-s9CWJv
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DetachedCriteria detachedCriteria){ ..K@'*u
return(List) getHibernateTemplate JqmxS*_P
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().execute(new HibernateCallback(){ HVHd@#pDZ
publicObject doInHibernate V'q?+p]
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(Session session)throws HibernateException { {O=PVW2S
Criteria criteria = #aua6V!"
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detachedCriteria.getExecutableCriteria(session); QhJuH_f 0
return criteria.list(); B4Fuvi
} J85S'cwZZ
}, true); V"Sa9P{y"
} !0Mx Bem
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public int getCountByCriteria(final EEn8]qJC
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DetachedCriteria detachedCriteria){ =`KA@~XH4
Integer count = (Integer) A/c #2
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getHibernateTemplate().execute(new HibernateCallback(){ Pxvf"SXX
publicObject doInHibernate {44#<A<
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(Session session)throws HibernateException { DP8%/CV!*
Criteria criteria = lS96Z3k"SB
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detachedCriteria.getExecutableCriteria(session); }1#prQ0F
return YZk.{#^ c
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criteria.setProjection(Projections.rowCount =G9I7Y@
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()).uniqueResult(); fpa~~E-
} :OFs"bC
}, true); PWBcK_4i%
return count.intValue(); KDS}"/
} N`HiNb
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用户在web层构造查询条件detachedCriteria,和可选的 >i_ #q$o
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 7tP%tp
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PaginationSupport的实例ps。 bn%4s[CVb4
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ps.getItems()得到已分页好的结果集 .|e8v _2J
ps.getIndexes()得到分页索引的数组 kW7$Gw]-
ps.getTotalCount()得到总结果数 4:9N]1JCb
ps.getStartIndex()当前分页索引 mIZ6[ ?
ps.getNextIndex()下一页索引 :2.<JUDM
ps.getPreviousIndex()上一页索引 0T7t.
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 _CMNmmp`e
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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 Yi j^hs@eV
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一下代码重构了。 DF>3)oTF
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我把原本我的做法也提供出来供大家讨论吧: aka)#0l .
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首先,为了实现分页查询,我封装了一个Page类: Xp.$FJ1)
java代码: w{*PZb4
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/*Created on 2005-4-14*/ 9:P\)'y?
package org.flyware.util.page; <L+1
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/** 5eiKMKW[
* @author Joa M@z_tR'3\
* .JOZ2QWm<
*/ oOHY+'V
publicclass Page { 7`f%?xVn0
Q5b9q$L$
/** imply if the page has previous page */ >xXC=z+g]
privateboolean hasPrePage; KM+[1Ze$
>6R3KJe
/** imply if the page has next page */ |R2p^!m
privateboolean hasNextPage; ,{; *b
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/** the number of every page */ =I aWf
privateint everyPage; c5_/i7
iu?gZVyka
/** the total page number */ {_mVfFG
privateint totalPage; G
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/** the number of current page */ UiVGOQq
privateint currentPage; d_Jj&:"l
"BVp37m;?
/** the begin index of the records by the current ve+bR
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query */ S:XsO9:{
privateint beginIndex; mPhu#oK'f
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/** The default constructor */ :..WL;gC
public Page(){ 5DDSo0E
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} \%7fm#z6
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/** construct the page by everyPage wTD}c1J(
* @param everyPage RRXp9{x`
* */ L9<\vJ
public Page(int everyPage){ ?;_*8Doq-a
this.everyPage = everyPage; 1BEs> Sm
} C5~n^I|
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/** The whole constructor */ :w-:B^VB
public Page(boolean hasPrePage, boolean hasNextPage, +TyN;e
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int everyPage, int totalPage, damG*-7Svx
int currentPage, int beginIndex){ |j-ng;
this.hasPrePage = hasPrePage; $_iE^zZaU^
this.hasNextPage = hasNextPage; 4&=</ok6`0
this.everyPage = everyPage; JEk'2Htx
this.totalPage = totalPage; <:Mz2Rg
this.currentPage = currentPage; aU~?&]
this.beginIndex = beginIndex; E%DT;1
} qY$ [2]
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/** *FktI\tS
* @return EK5$z>k>m
* Returns the beginIndex. yQ$]`hr;
*/ uorX;yekC
publicint getBeginIndex(){ %S"85#R5E
return beginIndex; tRpY+s~Fq
} k qL.ZR
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/** 8]Tv1Wc
* @param beginIndex ,~=]3qmbR
* The beginIndex to set. - om9 Z0e
*/ 0ki- /{;
publicvoid setBeginIndex(int beginIndex){ XPU>} 4{
this.beginIndex = beginIndex; |1"&[ .
} /OWwC%tM/
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/** ;Y[D#Ja-
* @return ^~.AV]t|
* Returns the currentPage. lOp.cU
*/ [{Jo(X
publicint getCurrentPage(){ :-5[0Mx=
return currentPage; W;yc)JB
} Eamt_/LKf
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/** B,cFvS
* @param currentPage e.skE>&
* The currentPage to set. |$b8(g$s)
*/ y]0O"X-G
publicvoid setCurrentPage(int currentPage){ x};~8lGT>t
this.currentPage = currentPage; >x JzV
} ~1%*w*
IJ&Lk=2E]
/** W-l+%T!
* @return xa@$cxt
* Returns the everyPage. X!qK[b@Z
*/ CNefk$/cR
publicint getEveryPage(){ nj'5iiV`]
return everyPage; 5XUm} D$
} Ga5*tWj
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/** **L&I5Hhm
* @param everyPage pX{wEc6}
* The everyPage to set. jwT` Z
*/ gDVsi
publicvoid setEveryPage(int everyPage){ Q{|%kU"
this.everyPage = everyPage; N?ccG\t
} .Pponmy
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/** UuWIT3W>%
* @return XZb=;tYo
* Returns the hasNextPage. o6px1C:
*/ @T~XwJ~
publicboolean getHasNextPage(){ dazNwn
return hasNextPage;
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} "t&=~eOe3
j*<J&/luYZ
/** <7VLUk}
* @param hasNextPage xeSch?}
* The hasNextPage to set. W|m(Jh[w]
*/ \Q|-Npw
publicvoid setHasNextPage(boolean hasNextPage){ ZK8)FmT_<O
this.hasNextPage = hasNextPage; ]JjS$VMauX
} X|T|iB,vT
J)>DsQ+Cj
/** SjB"#E)
* @return \jwG*a
* Returns the hasPrePage. 1H-Y3G>jN
*/ U
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publicboolean getHasPrePage(){ Q38+`EhLA
return hasPrePage; ng3ZK
} /=S@3?cQAB
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/** d\JaYizp
* @param hasPrePage \{ @m
* The hasPrePage to set. k_,7#:+
*/ QQS*r}>
publicvoid setHasPrePage(boolean hasPrePage){ YWK0.F,8a
this.hasPrePage = hasPrePage; =U3S"W %
} =O }^2OARo
s#s">hMrI
/** D<6$@ZJ
* @return Returns the totalPage. reN\|?0{
* Xe%J{
*/ (Lgea
publicint getTotalPage(){ v:P]o9Oj8
return totalPage; C8|V?bL
} X\h.@+f=
|@X^_L.!
/** -xHR6
* @param totalPage ;DuVb2~+
* The totalPage to set. HLW_Y|QaFo
*/ 'z.
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publicvoid setTotalPage(int totalPage){ ^~H{I_Y
this.totalPage = totalPage; @KTuG ?.
} <R]m(
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} u2oS Ci
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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 eP @#I^_
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个PageUtil,负责对Page对象进行构造: JD$g%hcVZa
java代码: YGo?%.X
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/*Created on 2005-4-14*/ tn5%zJ#+
package org.flyware.util.page; 8gP1]xD
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import org.apache.commons.logging.Log; /*qRbN
import org.apache.commons.logging.LogFactory; Mk}T
7%Y`j/
/** +-j-)WU?,
* @author Joa V'&;r'#O
* D5lQ0_IeW
*/ VvyRZMR
publicclass PageUtil { tP@NQCo
X<L=*r^C,=
privatestaticfinal Log logger = LogFactory.getLog >9{?]x
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(PageUtil.class); fkZHy|m
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/** /TpTR-\I0
* Use the origin page to create a new page *D?_,s
* @param page "U}kp#)
* @param totalRecords l
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* @return qPQIcJ
*/ lp
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publicstatic Page createPage(Page page, int |8k1Bap`z
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x
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totalRecords){ 0SI@`C*1o
return createPage(page.getEveryPage(), 1B4Qj`:+0
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page.getCurrentPage(), totalRecords); "N}t =3i$
} /f#b;qa,
~!$"J}d}<
/** Y:!L
* the basic page utils not including exception X<%D@$
Oh! {E5!)
handler [[$CtqLg
* @param everyPage ;:6\w!fc
* @param currentPage |`LH|6/
* @param totalRecords 0nb%+],pX
* @return page Ek L2nI
*/ u_k[<&$
publicstatic Page createPage(int everyPage, int `WayR^ 9
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currentPage, int totalRecords){ ''nOXl
everyPage = getEveryPage(everyPage); h$02#(RHJ
currentPage = getCurrentPage(currentPage); )=5&Q
int beginIndex = getBeginIndex(everyPage, LCB-ewy#E
\4N8-GwZQ
currentPage); RrMEDMhk6
int totalPage = getTotalPage(everyPage, nJ;^Sz17Q
sM-,95H
totalRecords); VhO%4[Jl
boolean hasNextPage = hasNextPage(currentPage, l!tR<$|
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totalPage); GKt."[seV
boolean hasPrePage = hasPrePage(currentPage); 36=aahXd\
(uC8M,I\
returnnew Page(hasPrePage, hasNextPage, pQiC#4b
everyPage, totalPage, ]DNPG"
currentPage, ]}v]j`9m%
b}K,wAx
beginIndex); pl]|yIZ
} hP"2X"kz&
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privatestaticint getEveryPage(int everyPage){ BP3Ha8/X
return everyPage == 0 ? 10 : everyPage; 1wR[nBg*|
} o Xm
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IXy6Yn9l
privatestaticint getCurrentPage(int currentPage){ oqJYbim
return currentPage == 0 ? 1 : currentPage; )]P(!hW.
} ,31 ?
Aa
/s4~Ij`be
privatestaticint getBeginIndex(int everyPage, int %B$ftsYXmu
RIMSXue*Ha
currentPage){ yx]9rD1cz
return(currentPage - 1) * everyPage; P{o)Ir8Tt
} ^QS`H@+Z
l)NkTZ<]
privatestaticint getTotalPage(int everyPage, int 2{=]Pf
]E/0iM5
totalRecords){ =%W:N|k
int totalPage = 0; &aRL}#U
0ID9=:J
if(totalRecords % everyPage == 0) Z*k(Q5&U
totalPage = totalRecords / everyPage; k'o[iKlu
else 8US#SI'x
totalPage = totalRecords / everyPage + 1 ;
GLf!i1Z
r9ulTv}X
return totalPage; Dj\nsc@e3
} _WEJ,0*#'
=.3#l@E!C
privatestaticboolean hasPrePage(int currentPage){ gcA:Q4
return currentPage == 1 ? false : true; X~r9yl>
} g4ZUh@b~
pq)
=
privatestaticboolean hasNextPage(int currentPage, .)
Ej#mk
k?fz @H8D(
int totalPage){ j#//U2VdN
return currentPage == totalPage || totalPage == A]bQUWt2
zQ=b|p]|W
0 ? false : true; z/J?!ee
} ;U'\"N9
3=
=["hO
,!{8@*!=s
} =p;cJ%#2]'
d_`MS@2
rnK]3Ust
Wr[LC&
x Q"uC!Gu4
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 q1VKoKb6\:
T~xVHk1
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 (u 7Lh>6%
6y^
zC?
做法如下: \Eh5g/,[
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 Zv
%>m
~<_#%R!
的信息,和一个结果集List: S>dHBR#AD
java代码: V48_aL
?$/::uo
qArR5OJ
/*Created on 2005-6-13*/ ZjxF@`H
package com.adt.bo; jemb/:E
5ngs1ZF@
import java.util.List; Iy_5k8]
AZ!/{1 Az
import org.flyware.util.page.Page; AW r2Bv
|5vJ:'` I
/** hrKeOwKHU
* @author Joa 8]#FvgX
*/ ('7?"npd
publicclass Result { )x!q;^Js9A
5, ;\zSz
private Page page; u{4P)DIQ
g"/n95k<
private List content; ajycYk9<m
}uDpf0;^
/** F$8:9eL,T
* The default constructor bhUE!h<
*/ &n1Vv_Lb
public Result(){ Kl. *Q
super(); 8U@f/P
} t`6]eRR
$ #!oejLD
/** gOg7:VPG
* The constructor using fields ]C^ #)7
* I;@q`Tm
* @param page tpSgbGzp
* @param content 9Buss+K?/h
*/ ]2-Qj)mZ]
public Result(Page page, List content){ 5 SQ!^1R 9
this.page = page; 0gqV>:
this.content = content; sO) H#G
} |}d^lQ9
B*G]Dr)e
/** cWQJ9.:7
* @return Returns the content. @|(cr: (=H
*/ ;jgf,fbM
publicList getContent(){ pBAAwHD
return content; `RY}g;
} DQ0S]:tC
ZW?h\0Hh
/** -9LvAV>
* @return Returns the page. P 'h39XoZ
*/ JcRxNH
)<"
public Page getPage(){ V~PGmn[V
return page; ]n4PM=hz
} F(1E@xs
LHtO|Utn(
/** (g;O,`|c,
* @param content `n6cpX5
* The content to set. Y9mhDznS
*/ Gw)y<h
public void setContent(List content){ L/fXP@u
this.content = content; ;*rGZ?%*
} 5%D`y|
J-+mdA
/** Dh^l:q+c
* @param page 7y^)n<'co
* The page to set. npeL1zO-$
*/ \r aP
publicvoid setPage(Page page){ 8T"L'{ggWB
this.page = page; G>pedE\
} 5!ngM
} ;r2DQg"#@
f IV"U
C1AX
MY{Kq;FvRP
"`K_5"F
2. 编写业务逻辑接口,并实现它(UserManager, #reR<qp&]
n$ByTmKxv
UserManagerImpl) =9,mt
K~
java代码: ]+G\1SN~
]|F`;} 7
Eet/l]e#a
/*Created on 2005-7-15*/ =0&XdxX
package com.adt.service; H.?`90IQ
e3n^$'/\r
import net.sf.hibernate.HibernateException; &LM@xt4"^[
VXCB.C"
import org.flyware.util.page.Page; 53/$8=
ZWGelZP~
import com.adt.bo.Result; b w1s?_P
{31X
/** )[Rwc#PA;
* @author Joa G l/3*J
*/ 2G|}ENC
publicinterface UserManager { 2KXFXR
&2:WezDF
public Result listUser(Page page)throws !rgXB(
^XyC[ G@[
HibernateException; &7kLSb&|;
bZSt<cH3
} =?L16mu1&
)%/ Ni^
"o%okN
no\G
>#
1V5N)ty
java代码: [*K9V/
y=8KNseW|
gs}&a3d7k
/*Created on 2005-7-15*/ ?b d&Av
package com.adt.service.impl; 1$))@K-I
Q~^v=ye
import java.util.List; &hVf=We
a@|`!<5
import net.sf.hibernate.HibernateException; tZ) ,Z<
DFfh!KKR$
import org.flyware.util.page.Page; Dt5AG
import org.flyware.util.page.PageUtil; "@ZwDg`
TH>uL;?=
import com.adt.bo.Result; @6_w{6:b
import com.adt.dao.UserDAO; CZy!nR!
import com.adt.exception.ObjectNotFoundException; _7v4S/V
import com.adt.service.UserManager; DM6(8df(
u<"-S63+
/** vzAY+EEx
* @author Joa 1OY
5tq
*/ z xgDaT
publicclass UserManagerImpl implements UserManager { &B8x0 yi
5:+x7Ed
private UserDAO userDAO; "kt7m
=H-BsX?P
/** /5KY6XxR
* @param userDAO The userDAO to set. oeVI 6-_S
*/ 0<-A2O),
publicvoid setUserDAO(UserDAO userDAO){ |p/[sD+M
this.userDAO = userDAO; 9~ V(wG
} (CAVOed
,o2x,I
/* (non-Javadoc) JWM4S4yZHR
* @see com.adt.service.UserManager#listUser R74RJi&
iMYJVB=
(org.flyware.util.page.Page) fuf'r>1n
*/ |v>W
public Result listUser(Page page)throws "2!5g )iO
CW@EQ3y0
HibernateException, ObjectNotFoundException { ;[C_ho
int totalRecords = userDAO.getUserCount(); c[6<UkH7
if(totalRecords == 0) z/o&r`no
throw new ObjectNotFoundException 22d>\u+c
Yg!fEopLb
("userNotExist"); GOCe&?
page = PageUtil.createPage(page, totalRecords); M%13b$i~f
List users = userDAO.getUserByPage(page); J"eE9FLM
returnnew Result(page, users); RXO}mu]Iu
} M&(0n?R"R
7
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} P` CQ)o
]<iD'=a
w V v@
y7b>>|C
,[| i^
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 2j^8{Agz
V#&S&dn
询,接下来编写UserDAO的代码: Y,KSr|vG
3. UserDAO 和 UserDAOImpl: q\s>Oe6$
java代码: 1N.weey}W
qpB8ujj<V
/u"K`y/*j\
/*Created on 2005-7-15*/ /KgP<2p
package com.adt.dao; '8^>Z.~V
of_Om$
import java.util.List; ['c*<f"
D2
7?Twhs.O
import org.flyware.util.page.Page; GKXd"8z]
wx/*un%2
import net.sf.hibernate.HibernateException; aH$DEs
e&pt[W}X%u
/** H"JzTo8u
* @author Joa F @!9rl'
*/ meD?<g4n~"
publicinterface UserDAO extends BaseDAO { s9b+uUt%
e>HdJ"S`
publicList getUserByName(String name)throws t;
#D,gx
8(@(G_skp
HibernateException; =6,w~|W
DoEN`K\U
publicint getUserCount()throws HibernateException; Cm6%wAzC
$.Qq:(O:6
publicList getUserByPage(Page page)throws d-UQc2r
Eye.#~
HibernateException; dr=h;[Q'
?&XpwJw:~
} 8 }OII\
[@/x
=eeZtj.
4^w`]m
QL@}hw.F
java代码: 8Vm)jnM
4V
5
-[A=\]RfJ
/*Created on 2005-7-15*/ x1.yi-
package com.adt.dao.impl; eBlB0P
LyT[
import java.util.List; pTcN8E&Unz
D7,{p2<2T
import org.flyware.util.page.Page; &Y8S! W@4
d+6-ten
import net.sf.hibernate.HibernateException; qJJ~#W)
import net.sf.hibernate.Query; &Ht5!zuW,
vy5SBiK
import com.adt.dao.UserDAO; VL@eR9}9K
\yo)oIi[p
/** 7,D6RP(b
* @author Joa >KCnmi
*/ FJ
V!B&
public class UserDAOImpl extends BaseDAOHibernateImpl pM_oIH'8:
-* piC(
implements UserDAO { .^FdO$"
g5hMZPOmP
/* (non-Javadoc) a.G;s2>
* @see com.adt.dao.UserDAO#getUserByName OYk/K70l3
05[k@f$n
(java.lang.String) ,=t}|!jx
*/ {edjvPlk
publicList getUserByName(String name)throws _*dUH5
gO]jeO
HibernateException { `BKV/Xl
String querySentence = "FROM user in class p>0n~e
y(Ck j"
com.adt.po.User WHERE user.name=:name"; $r/tVu2!W
Query query = getSession().createQuery +J(@.
+FlO_=Bu
(querySentence); |7E1yu
query.setParameter("name", name); Z/[ww8b.
return query.list(); 8\_ YP3
} #bdSH)V
~e<h2/Xc
/* (non-Javadoc) }>~]q)]
* @see com.adt.dao.UserDAO#getUserCount() : x@j)&
*/ ZE0D=
publicint getUserCount()throws HibernateException { V.kRV{43
int count = 0; rh 7%<xb>
String querySentence = "SELECT count(*) FROM &0%x6vea
LIMPW w g
user in class com.adt.po.User"; GUdVsZjz(
Query query = getSession().createQuery Jz6zJKcA
zQyt 1&!
(querySentence); T!Eyq,]
count = ((Integer)query.iterate().next "~ eF%}.
`\#J&N
()).intValue(); {G4{4D }
return count; yM*f}S/
(
} rIZ^ix-N
u8i!Fxu
/* (non-Javadoc) ^|ln q.j
* @see com.adt.dao.UserDAO#getUserByPage 4 .d~u@=
V/,F6
(org.flyware.util.page.Page) N3QDPQ
*/ f"g-Hbl5
publicList getUserByPage(Page page)throws t7qY!S (
8UN7(J
HibernateException { I`FqZw
String querySentence = "FROM user in class DE _<LN
h}cR>
com.adt.po.User"; 7C@%1kL
Query query = getSession().createQuery "3X~BdH&J
KO5! (vi@
(querySentence); 3zuYN-;
query.setFirstResult(page.getBeginIndex()) jK9#.
0
.setMaxResults(page.getEveryPage()); hNF.
return query.list(); 7,&M6<~
} { x/~gp
;7w4BJcq']
} eg
Zb)pP
4vbtB2
LP-_i}Kq
/D&7 \3}
/r@~"Rx '
至此,一个完整的分页程序完成。前台的只需要调用 h;?H4j
4<Q^/-W
userManager.listUser(page)即可得到一个Page对象和结果集对象 Rx%SeM2
;<)<4N"
的综合体,而传入的参数page对象则可以由前台传入,如果用 xN=:*#Z"pb
Emx`+9
webwork,甚至可以直接在配置文件中指定。 KBkS>0;X
Cqc5jx0)
下面给出一个webwork调用示例: 0mD=Rjb*a
java代码: \zGmZZ
f?|cQ[#t!\
q}0xQjpo
/*Created on 2005-6-17*/ @<,YUp,%S
package com.adt.action.user; b'$fr6"O1
p`2w\P3;)
import java.util.List; uKE?VNC]
EX9os
import org.apache.commons.logging.Log; |v31weD8
import org.apache.commons.logging.LogFactory; u[G`_Y{=EM
import org.flyware.util.page.Page; B #zU'G*Y
MiB}10
import com.adt.bo.Result; ~gJJ@j 0n
import com.adt.service.UserService; <b$.{&K
import com.opensymphony.xwork.Action; }6!*H!
2{fPQQ;#
/** iX\]-_D
* @author Joa Qy_! +q
*/ S<bsrS*$
publicclass ListUser implementsAction{ {Jn*{5tZ>
vm
Y*K
privatestaticfinal Log logger = LogFactory.getLog 1NQstmd{
JuTIP6
/G
(ListUser.class); "D1u2>(
i]M:ntB"
private UserService userService; o1?bqVF;6
99tKs
private Page page; $=GnoS
TM2pE/P
privateList users; %6eQ;Rp*
+(l(|lQy$
/* %kSpMj|
* (non-Javadoc) &h_do8R
* h#Q Sx@U6
* @see com.opensymphony.xwork.Action#execute() >hsvRX\_`
*/ yhJA{nL=
publicString execute()throwsException{ QssU\@/Q
Result result = userService.listUser(page); q6a7o=BP]
page = result.getPage(); D +Ui1h-
users = result.getContent(); w:+wx/\
return SUCCESS; Z.rR)
} (+lCh7.
('Doy1L
/** nkii0YB!
* @return Returns the page. 8^>qzaf
8
*/ C^8n;i9
public Page getPage(){ {RPZq2Tpc
return page; ZxvBo4>tH
} Kdr7JQYzuz
Ia!B8$$'RP
/** }{S
f*
* @return Returns the users. vE<z0l
*/ qnCJrY6]
publicList getUsers(){ 5nSi29C
return users; x}B_;&>&"_
} >3&Oe
?@YABl
/** S?K x:]
* @param page %.[jz,;)
* The page to set. 5eJMu=UpR
*/ 09L"~:rg
publicvoid setPage(Page page){ Q$XNs%7w5,
this.page = page; (N
0kTi]b
} gof'NT\c
%&Q9WMo
/** U+2U#v=<
* @param users -gK*&n~
* The users to set. vn5O8sD
*/ odaCKhdk
publicvoid setUsers(List users){ L2<IG)oXU
this.users = users; <2,NWn.
} :N>n1tHL;A
zPn2
/** q\]"}M8
* @param userService vn(ji=
* The userService to set. }Md5a%s<
*/ fs,]%g^
publicvoid setUserService(UserService userService){ jhF&
this.userService = userService; X5w_ }Nhe
} ])tUXU>
} }{y(&Oy3Y
7*I:cga
)p!.V(,
=Owr
l'@|T
v-ZTl4j$
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, -J'0qN!
Zc|V7+Yx
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 V''?kVJ
DqN<bu2
么只需要: "
.<>(bE
java代码: s=[T,:Z
^sqTgrG
u}QcyG^
<?xml version="1.0"?> U"L7G$
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork MR3\7D+9y
Y6:b
1.0//EN" "http://www.opensymphony.com/xwork/xwork- \qZ>WCp>r
J{qsCJiB
1.0.dtd"> T:!f_mu|
&w'1
<xwork> e gdbv
*VV#o/Qp
<package name="user" extends="webwork- Ouos f1
#ni:Bwtl{
interceptors"> G5,g$yNs
KJP}0|[
<!-- The default interceptor stack name qLWM,[Og
ec3zoKtV
--> J5"d|i
<default-interceptor-ref <19A=
_MLbJ
name="myDefaultWebStack"/> 5`\"UC7?%
/hp
[ +K
<action name="listUser" %Kzu&*9Hb
Vf#g~IOI
class="com.adt.action.user.ListUser"> o*sss
<param nI7v:h4
A~M .v0
name="page.everyPage">10</param> x^~@`]TV^
<result z0T9tN!(
7#+>1 "\
name="success">/user/user_list.jsp</result> C'.^2s#e8
</action> }Yargj_Gn
S;iJQS
</package> TD.t)
Dn[u zY6
</xwork> t>}(`0
VOGx
z2~\
b3G
?<efKs
-Dy":/Bk
+F]=Z
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 >qS2ha
y&L Lx[8^
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。 Fk`|?pQm
a3J'
c
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 `MC5_SG 1
3<O=,F
jp880}
Rrw6\iO
J b?x-%Za
我写的一个用于分页的类,用了泛型了,hoho &t,"k'p
$bFH%EA.
java代码: ~xt]g zp{
"h7Np/ m3
^H`4BWc
package com.intokr.util; ?h)T\z
WP5Vev9*+
import java.util.List;
e(H{C
X:m m<4
/** 3R<VpN){
* 用于分页的类<br> PwnfXsR
* 可以用于传递查询的结果也可以用于传送查询的参数<br> dR!x)oO=
* SZD7"m4
* @version 0.01 B|ctauJ
* @author cheng sL],@z8<k
*/ {RN-rF3w
public class Paginator<E> { sB0m^Y'
privateint count = 0; // 总记录数 JH._/I
privateint p = 1; // 页编号 3}5Ya\x
privateint num = 20; // 每页的记录数 }CM#jN?(
privateList<E> results = null; // 结果 snP]&l+
d+p^fBz
/** :%<'('S|
* 结果总数 .^8rO,H[
*/ U;#G$
publicint getCount(){ ($Q|9>5,
return count; [&pMU)
} 1EWskmp
Ys]cJ]
publicvoid setCount(int count){ -_BX\iP{
this.count = count; cq~~a(IS
} 2oo\ SmO]
J\hqK*/8
/** Ze?n Q-
* 本结果所在的页码,从1开始 ?{%"v\w
* 'HJ<"<
* @return Returns the pageNo. .UYhj8
*/ =g |5VXW5
publicint getP(){ !NMiWG4R
return p; D< 0))r
} e"|ZTg+U
i,2eoM)FB
/** 3LZvlcLb
* if(p<=0) p=1 mhI
* {7Hc00FM
* @param p <07]w$m/
*/ Mtc -
publicvoid setP(int p){ ]fSpG\yU
if(p <= 0) e_}tK1XY
p = 1; |3BxNFe`%
this.p = p; SN]Na<P
} LtGjHB\+
O-!Q~;3][
/** W9;9\k
* 每页记录数量 piFZu/~Gq\
*/ 8WpZ"
publicint getNum(){ @w(X}q1
return num; =7F?'&LC
} h0")NBRV&
pGr4b:N
/** v oO7W"
* if(num<1) num=1 R`M@;9I.@
*/ HLPY%VeD
publicvoid setNum(int num){ K^IB1U$
if(num < 1) 4'"WD0
num = 1; =R)w=ce
this.num = num; /4;Sxx-
} vXg^K}a#
_<'?s>(U'
/** T1%}H3
* 获得总页数 K5F;/KR"
*/ ^ywDa^;-
publicint getPageNum(){ uSv]1m_-]
return(count - 1) / num + 1; H.[nr:
} %<`sDO6Q?
.\:MB7p
/** tAkv'.
* 获得本页的开始编号,为 (p-1)*num+1 5> !N)pA
*/ VAA="yN
publicint getStart(){ <fHN^O0TS
return(p - 1) * num + 1; LtPaTe
} Hc-up.?v'v
q2/kegAT
/** }*S`1IWMj
* @return Returns the results. S~)_=4Z
*/ .)<l69ZD Z
publicList<E> getResults(){ \Nk578+AA
return results; sQ+s3x1y
} 0"Zxbgu)
,y@WFRsx
public void setResults(List<E> results){ R ^ZOcONd-
this.results = results; q2s=>J';
} YF>15{H
#kE8EhQZ
public String toString(){ Gd$!xN%O
StringBuilder buff = new StringBuilder /x<uv_"
WJk3*$=
(); 5n1`$T.WG
buff.append("{"); L`(\ud
buff.append("count:").append(count); '
H4m"
buff.append(",p:").append(p); #CcEI
buff.append(",nump:").append(num); r;p@T8k
buff.append(",results:").append o#WECs>
M(I%QD
(results); 0sH~H[ap
buff.append("}"); smn~p/u
return buff.toString(); MI-S}Qoe
} lbPn<
"&o"6ra}
} dnV&U%fO
q=*bcDu
pfw`<*e'