Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 A!bH0=<I
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 'v?"TZ
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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 3H_%2V6#V1
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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 [/'=M h
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分页支持类: f0Zn31c^
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java代码: JA(M'&q4
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package com.javaeye.common.util; oy<
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import java.util.List; fJ8Q\lb<_
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publicclass PaginationSupport { A!n)Fpk
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publicfinalstaticint PAGESIZE = 30; g]a5%8*{
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privateint pageSize = PAGESIZE; GDBxciv
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privateList items; c*:H6(u
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privateint totalCount;
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privateint[] indexes = newint[0]; |o0?u:
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privateint startIndex = 0; P{tH4V23T
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public PaginationSupport(List items, int 25m6/Y
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totalCount){ SRfnT?u6
setPageSize(PAGESIZE); b8$(j2B~
setTotalCount(totalCount); V3] Z~@
setItems(items); o n+:{ad
setStartIndex(0); N{o3w.g
} E>2~cC*
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public PaginationSupport(List items, int cZd{K[fuK
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totalCount, int startIndex){ jcVK4jW
setPageSize(PAGESIZE); 1 Ka,u20
setTotalCount(totalCount); ;E0aTV)Zp
setItems(items); ,MRAEa2
setStartIndex(startIndex); i*9Bu;
} SZ )AO8&
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public PaginationSupport(List items, int 6'YsSde".
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totalCount, int pageSize, int startIndex){ fAHf}j
setPageSize(pageSize); {T2=bK~
setTotalCount(totalCount); Kp.d#W_TX
setItems(items); y?4%eD
setStartIndex(startIndex); ^;[|,:8f7L
} H1^m>4ll9
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publicList getItems(){ nJ{vO{N
return items; }}4u>1,~
} y)%CNH)*x
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publicvoid setItems(List items){ <1xs
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this.items = items; uhJnDo
} 5q Y+^jO]o
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publicint getPageSize(){ IA&NMf;{
return pageSize; ,y%4QvG7a
} :K]&rGi,
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publicvoid setPageSize(int pageSize){ R3,O;9i
this.pageSize = pageSize; dnXre*rhz
} wx2EMr
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publicint getTotalCount(){ Rz\:)<G
return totalCount; {~u#.(
} m?4L>'
THcK,`lX@
publicvoid setTotalCount(int totalCount){ sH_5.+,`
if(totalCount > 0){ Z&w/JP?
this.totalCount = totalCount; `<3xi9
int count = totalCount / gZ b+m
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pageSize; QgZ`~
if(totalCount % pageSize > 0) ljJi|+^$
count++; qY^@^)b[
indexes = newint[count]; FWu[{X;
for(int i = 0; i < count; i++){ T|fmO<e*n
indexes = pageSize * zJ9[),;7B
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i; kafRuO~$
} 40ZHDtIu<
}else{ sCi"qtHP
this.totalCount = 0; y8k*{1MuO
} rr;p;
} ,|u^-J@
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publicint[] getIndexes(){ xQ{n|)i>
return indexes; "?r=n@Kv
} AXmW7/Sj"
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publicvoid setIndexes(int[] indexes){ d \[cFe1d
this.indexes = indexes; /j|Rz5@=
} F[HMX4
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publicint getStartIndex(){ 8;vpa*
return startIndex; o fw0_)!Q
} ~lSdWUk>
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publicvoid setStartIndex(int startIndex){ miCW(mbO8
if(totalCount <= 0) )4@La&
this.startIndex = 0; G5K_e:i
elseif(startIndex >= totalCount) %n7mN])
this.startIndex = indexes )08mG_&atL
sb^%eUU])
[indexes.length - 1]; SmR"gu
elseif(startIndex < 0) Y%"6
this.startIndex = 0; 9f+S-!
else{ bm Hl\?
this.startIndex = indexes ;WG6|QgV?-
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[startIndex / pageSize]; s2'] "wM
} nm3/-Q},
} xdqiogu e
/`)>W :
publicint getNextIndex(){ 'i5V6yB
int nextIndex = getStartIndex() + #4Z]/D2G
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pageSize; qwz_.=5E6
if(nextIndex >= totalCount) _t+.I9kQ
return getStartIndex(); "h >B`S
else O
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return nextIndex; =5PNH 2
} f-M 9OI
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publicint getPreviousIndex(){ |`
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int previousIndex = getStartIndex() - 7G^`'oZ
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pageSize; xbeVqP
if(previousIndex < 0) l[)ZEEP
return0; 5qx,b&^w
else AnUOv2
return previousIndex; Z\@m_/g
} I,pI2
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} "N|gU;~W
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抽象业务类 ZV?~~_9
java代码: H%AF,
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/** No1*~EQ
* Created on 2005-7-12 w&F/P]1
*/ H$j`75#u?-
package com.javaeye.common.business; SW^/\cJ^
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import java.io.Serializable; @\_l%/z{
import java.util.List; :mpR}.^hv
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import org.hibernate.Criteria; ^{vf|zZ _
import org.hibernate.HibernateException; /<\B8^yQ
import org.hibernate.Session;
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import org.hibernate.criterion.DetachedCriteria; g'F{;Ur
import org.hibernate.criterion.Projections; ;is *[r\|1
import H+VKWGmfG
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org.springframework.orm.hibernate3.HibernateCallback; G31??L:<
import <o\2-fWvY
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org.springframework.orm.hibernate3.support.HibernateDaoS jw^Pt~@
svBT~P0x
upport; I`O)I&KH
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import com.javaeye.common.util.PaginationSupport; 4IW7^Pq`P
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public abstract class AbstractManager extends h.`U)6*?&N
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HibernateDaoSupport { cnrS.s=
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privateboolean cacheQueries = false; lQnl6j
cjd Z.jR2
privateString queryCacheRegion; ;g0p`wV
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publicvoid setCacheQueries(boolean *t,J4c
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cacheQueries){ yLo{^4a.
this.cacheQueries = cacheQueries; [ NSsT>C
} X)tf3M
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publicvoid setQueryCacheRegion(String 2I2#o9(Ar
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queryCacheRegion){ E903T' 's
this.queryCacheRegion = r dc}e"v
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queryCacheRegion; +:s]>R eDa
} q
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publicvoid save(finalObject entity){ |+ ^-b}0
getHibernateTemplate().save(entity); }Z|uLXaz
} xKKR'v:o\
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publicvoid persist(finalObject entity){ YEEgDw]BQ
getHibernateTemplate().save(entity); x}w"2[fL
} '}`|QJ
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publicvoid update(finalObject entity){ 1lxsj{>U
getHibernateTemplate().update(entity); q*<Fy4j
} NbD"O8dL~E
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publicvoid delete(finalObject entity){ B" -gK20vY
getHibernateTemplate().delete(entity); T@n-^B !Xq
} 4)o_gm~6c4
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publicObject load(finalClass entity, Al^n&Aa+\
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finalSerializable id){ WhO;4-q)2
return getHibernateTemplate().load yAu-BObD
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(entity, id); v}=3
} b9ON[qOMN
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publicObject get(finalClass entity, Jl"),;Od
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finalSerializable id){ f PoC
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return getHibernateTemplate().get I[~EQ{Iz
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(entity, id); Su<Ggv"
} Fh XR!x^
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publicList findAll(finalClass entity){ C] <K s
return getHibernateTemplate().find("from ~zklrBn&
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" + entity.getName()); UF[2Rb8?
} @quNVx(y
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publicList findByNamedQuery(finalString 'L*nC
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namedQuery){ RLypWjMx$
return getHibernateTemplate BReNhk)S
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().findByNamedQuery(namedQuery); gr'M6&>
} C+r<DC3
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publicList findByNamedQuery(finalString query, IT,TSs/Y
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finalObject parameter){ U9D4bn D
return getHibernateTemplate 4:\s.Z{!3
xw*T?!r=V
().findByNamedQuery(query, parameter); _P!J0
} FhgO5@BO
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publicList findByNamedQuery(finalString query, ti:qOSIDTA
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finalObject[] parameters){ :X>%6Xj?RV
return getHibernateTemplate (+<SR5,/3
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().findByNamedQuery(query, parameters); JM5w`=
} i|X ;n
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publicList find(finalString query){ XEF|B--,
return getHibernateTemplate().find vUGEzC M
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(query); #zC_;u$
} P8K{K:T
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publicList find(finalString query, finalObject kji*7a?y
)bZS0f-
parameter){ esH>NH_
return getHibernateTemplate().find 'CT8vt;
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(query, parameter); @[0zZX2EE
} =`5Xx(
p=U*4[9k
public PaginationSupport findPageByCriteria ;z;O}<8s
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(final DetachedCriteria detachedCriteria){ uBLI!N-G
return findPageByCriteria nB ?$W4
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); &?mH[rG"
} >Vr+\c
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public PaginationSupport findPageByCriteria Z(p kj
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(final DetachedCriteria detachedCriteria, finalint [HB>\
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startIndex){ xzg81sV7
return findPageByCriteria @U6Iw"@
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(detachedCriteria, PaginationSupport.PAGESIZE, G>{Bij44
xU#f>@v!
startIndex); 7/lXy3B4
} {J2*6_
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public PaginationSupport findPageByCriteria +E7s[9/r
w-?_U7'
(final DetachedCriteria detachedCriteria, finalint dzMlfJp
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pageSize, G(F}o]
finalint startIndex){ K_
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return(PaginationSupport) Zr,:i
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getHibernateTemplate().execute(new HibernateCallback(){ 59:Xu%Hp
publicObject doInHibernate i-)OY,
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(Session session)throws HibernateException { GU'/-6-T
Criteria criteria = '#REbY5ev
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detachedCriteria.getExecutableCriteria(session); Fyy)665x/
int totalCount = A+*M<W
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((Integer) criteria.setProjection(Projections.rowCount RnV
)*
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()).uniqueResult()).intValue(); 7Z0fMk
criteria.setProjection mt$0p|B8
v'(p."g
(null); bcFG$},k
List items = e[f}L xln
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criteria.setFirstResult(startIndex).setMaxResults Dbt"}#uit;
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(pageSize).list(); \<WRk4D
PaginationSupport ps = LYb@0O<w
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new PaginationSupport(items, totalCount, pageSize, [+EmV >Y
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startIndex); XVcY?_AS#
return ps; (LzVWz m
} Lu,72i0O ^
}, true); .}Va~[0j
} 5[3vup?
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public List findAllByCriteria(final F)_zR
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DetachedCriteria detachedCriteria){ 555j@
return(List) getHibernateTemplate NO5\|.,Z
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().execute(new HibernateCallback(){ F}p)Q$0
publicObject doInHibernate ?S^ U-.`
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(Session session)throws HibernateException { P%MYr"<$E
Criteria criteria = JGl0
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^ Q]I)U
detachedCriteria.getExecutableCriteria(session); W8{g<.
/
return criteria.list(); z\wY3pIr2
} KITC,@xE_O
}, true); )Y.H*ca
} -?L~\WJAL
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public int getCountByCriteria(final PhTMXv<cE
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DetachedCriteria detachedCriteria){ 5Fa.X|R~
Integer count = (Integer) Fq\vFt|m<
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getHibernateTemplate().execute(new HibernateCallback(){ Yxik.S+G
publicObject doInHibernate KQGdV{VFs
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(Session session)throws HibernateException { ,*_=w^;Rr
Criteria criteria = 6
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detachedCriteria.getExecutableCriteria(session); \\w<.\Yh
return <y4hK3wP
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criteria.setProjection(Projections.rowCount >@?!-Fy5
h"R{{yf2
()).uniqueResult(); }7)iLfi
} E6+c{4 1B
}, true); wD+4#=/j
return count.intValue(); &c[.&L,w4
} k# -u!G
} ndW]S 7
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用户在web层构造查询条件detachedCriteria,和可选的 W}^X;f
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 t5t!-w\M$+
g~ubivl2
PaginationSupport的实例ps。 T$w`=7
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ps.getItems()得到已分页好的结果集 #Y|t,x;
ps.getIndexes()得到分页索引的数组 Lt'FA
ps.getTotalCount()得到总结果数 +UvT;"
ps.getStartIndex()当前分页索引 /:S&1'=
ps.getNextIndex()下一页索引 3`
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ps.getPreviousIndex()上一页索引 AN)exU ?
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 7bk=D~/nSg
N$&)gI:
,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 T( LlNq
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一下代码重构了。 k`aHG8S\
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我把原本我的做法也提供出来供大家讨论吧: PvHX#wJ
#{f%b,.yxt
首先,为了实现分页查询,我封装了一个Page类: _|^cudRv
java代码: a+!r5689
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/*Created on 2005-4-14*/ X}fu $2
package org.flyware.util.page; :<QmG3F
a8w/#!^34
/** "A9qC*6[
* @author Joa Pl/}`H:R&
* q0sdL86
*/ ;rj|>
publicclass Page { 2=]Xe#5J=
[H4)p ,R
/** imply if the page has previous page */ _GW, 9s^A
privateboolean hasPrePage; 'lWgHmE
#ULjK*)R
/** imply if the page has next page */ qT153dNA&
privateboolean hasNextPage; EX"o9'
k`(Cwp{Oc
/** the number of every page */ Kry^47"
privateint everyPage; *!5X!\e_
B'}pZOa[Wb
/** the total page number */ +{b3A@f|F
privateint totalPage; Rlwewxmr
R!z32 <5k
/** the number of current page */ bnzIDsw!Q
privateint currentPage; !,Uzt1K:
v\ <4y P
/** the begin index of the records by the current O[<YYL0
Neb")
query */ [sc4ULS &
privateint beginIndex; jCK 0+,;
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/** The default constructor */ x\K9|_!
public Page(){ . UaLP
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} h anS8
hd%O\D?
/** construct the page by everyPage aGs\zCAP
* @param everyPage (dnaT-M3
* */ 7*>(C*q=
public Page(int everyPage){
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this.everyPage = everyPage; ]!'}{[1}
} 0\KDa$'1k
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/** The whole constructor */ \Y$@$)
public Page(boolean hasPrePage, boolean hasNextPage, D:=Q)Uh0I
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f?BApm
int everyPage, int totalPage, [AN= G!r
int currentPage, int beginIndex){ qA>C<NL
this.hasPrePage = hasPrePage; ?'/#Gt`
this.hasNextPage = hasNextPage; M{)|9F
this.everyPage = everyPage; Dd'4W
this.totalPage = totalPage; lU8X{SV!
this.currentPage = currentPage; N_o|2
this.beginIndex = beginIndex; .T*89cEu
} j21>\K!p
a0)] W%F
/** LB\+*P6QM
* @return ;=lQMKx0
* Returns the beginIndex. @!KG;d:l
*/ <tI_u ~P
publicint getBeginIndex(){ 2q}lSa7r
return beginIndex; QdK
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} &]S\GnqlU]
j<PpCL_8%
/** +@BjQ|UZ
* @param beginIndex :TRhk.
* The beginIndex to set. X$(YCb
*/ +2JC**)I
publicvoid setBeginIndex(int beginIndex){ %(ms74R+
this.beginIndex = beginIndex; KYM%U"j D
} _)a!g-Do7
cL+bMM$4r~
/** C+vk9:"
* @return B#, TdP]/
* Returns the currentPage. EY}*}- 3
*/ Z@gEJ^"yA"
publicint getCurrentPage(){ (Y~gItej
return currentPage; FB }8
} 8Y
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tk66Ggi[K
/** fD~f_Wr
* @param currentPage 8c<OX!
* The currentPage to set. a"!r]=r
*/ +L-(Lz[p
publicvoid setCurrentPage(int currentPage){ |wkUnn4UB8
this.currentPage = currentPage; \xjI=P'-25
} _r?.%]\.
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/** / TAza9a
* @return Rc#c^F<
* Returns the everyPage. ?X nKKw\
*/ Psw<9[
publicint getEveryPage(){ NxrfRhaU3
return everyPage; 3Q2z+`x'
} TQ69O +
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/** Jk_}y
* @param everyPage .2x`Fj;o1
* The everyPage to set. v@Bk)Z
*/ +P|Z1a -jB
publicvoid setEveryPage(int everyPage){ 7CSd}@71\
this.everyPage = everyPage; (
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} r#\Lq;+-B
qs3V2lvYw{
/** ;G4g;YHy|
* @return f19'IH$n{
* Returns the hasNextPage. >*"1`vcxF
*/ wj-z;YCV
publicboolean getHasNextPage(){ d6zfP1lQ
return hasNextPage; Fm`c
} fa2hQJ02
f<LRM
/** aB2t /ua
* @param hasNextPage !"bU|a
* The hasNextPage to set. -^WW7 g`
*/ W3y9>]{x^
publicvoid setHasNextPage(boolean hasNextPage){ [_1K1i"m
this.hasNextPage = hasNextPage; li
} gn6 @x
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o,"
/** `FRdo
* @return arb'.:[z^
* Returns the hasPrePage. !b?`TUt
*/ gbT1d:T
publicboolean getHasPrePage(){ e6
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return hasPrePage; ]z"7v
} -jcgxQH53
FSHC\8siS
/** "4WwiI9
* @param hasPrePage ANlzF&K
* The hasPrePage to set. !d{Ijs'T
*/ VPUm4%?p$
publicvoid setHasPrePage(boolean hasPrePage){ FV5~sy
this.hasPrePage = hasPrePage; 2i~zAD'
} [=& tN)_
r@ v&~pL
/** ;C~:C^Q\H
* @return Returns the totalPage. MOIMW+n
* ?xYoCn}Z
*/ 8w9?n3z=}
publicint getTotalPage(){ p(pL"
return totalPage; ^9
Pae)
} b9"HTQHl
Y%#r&de
/** Cd'K~Ch3
* @param totalPage b&I{?'"% 8
* The totalPage to set. mM\jU5P:^
*/ hDD]Kc;G^1
publicvoid setTotalPage(int totalPage){ /YD2F
this.totalPage = totalPage; BB3wG*q
} SoNT12>
QO <.l`F
} ;)'
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i~uoK7o|G
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 ]=jpqxlx
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个PageUtil,负责对Page对象进行构造: DW0UcLO
java代码: DRmN+2I
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/*Created on 2005-4-14*/ %-#rzeaW
package org.flyware.util.page; f ]DO2r
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import org.apache.commons.logging.Log; Nj$h/P
import org.apache.commons.logging.LogFactory; s#%P9A
/4Jm]"
/** N2\{h(*u
* @author Joa }o2e&.$4d
* +~!\;71:f
*/ oh.8WlI
publicclass PageUtil { d
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:y3e-lr
privatestaticfinal Log logger = LogFactory.getLog ILMXWw
7N}==T89[
(PageUtil.class); faPgp
)=6o,
/** #({ 9M
* Use the origin page to create a new page Gu5%P ou
* @param page +w9X$<?_
* @param totalRecords %tT=q^%5
* @return LRKl3"M
*/ CINC1Ll_24
publicstatic Page createPage(Page page, int 6/l{e)rX2o
w6@8cNXK
totalRecords){ N^xk.O_TO
return createPage(page.getEveryPage(), AlhPT (
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page.getCurrentPage(), totalRecords); 2pV@CT
} ]2@g 5H}M
*$v`5rP
/** tP0!TkTo9
* the basic page utils not including exception
hp!. P1b
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handler @V71%D8{
* @param everyPage #/2W RN1L
* @param currentPage XS`=8FQ
* @param totalRecords $p~X"f?0
* @return page uH=^ILN.
*/ ;SVAar4r
publicstatic Page createPage(int everyPage, int !1fAW!8
}8)iFP&"
currentPage, int totalRecords){ +nm?+F
everyPage = getEveryPage(everyPage); \p{$9e;8yT
currentPage = getCurrentPage(currentPage); khS >
int beginIndex = getBeginIndex(everyPage, boWaH}?0'
~pve;(e=
currentPage); 5MmSQ_
int totalPage = getTotalPage(everyPage, dBM> ;S;v
`cn}}1Lg]
totalRecords); i[rXs/]
boolean hasNextPage = hasNextPage(currentPage, Lk:Sju
{>8u/
totalPage); L__J(6,V2
boolean hasPrePage = hasPrePage(currentPage); vu=`s|R
Lzy Ix!S
returnnew Page(hasPrePage, hasNextPage, r E<Ou"
everyPage, totalPage, Ub| -Q
currentPage, >gGdzL
L6IF0`M<,I
beginIndex); eO?@K$I
} X+;{&Efrl
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privatestaticint getEveryPage(int everyPage){ x>*#cOVz;C
return everyPage == 0 ? 10 : everyPage; BY!M(X
jrZ
} M?m)<vMr*
.C?rToCY
privatestaticint getCurrentPage(int currentPage){ 9w08)2$Na
return currentPage == 0 ? 1 : currentPage; ^y p`<=
} i)mQ?Y#o
\*.u(8~2o
privatestaticint getBeginIndex(int everyPage, int o%V%@q H
HqKI|^
currentPage){ {Tl |>\[P
return(currentPage - 1) * everyPage; f<}>*xH/k
} !K5D:x
i\94e{uty[
privatestaticint getTotalPage(int everyPage, int &I=F4 z
LG>lj$hO
totalRecords){ -na oM
int totalPage = 0; 'Nn>W5#))
PAHkF&
if(totalRecords % everyPage == 0) d>r_a9 .u
totalPage = totalRecords / everyPage; #Y;tobB
else N\Li/
totalPage = totalRecords / everyPage + 1 ; 2/M:KR
QZ^P2==x
return totalPage; N9jSiRJ
} aK4ZH}XHE"
``9`Xq
privatestaticboolean hasPrePage(int currentPage){ =BNS3W6
return currentPage == 1 ? false : true; [7*$Sd
} <Z58"dg.5
+tSfx
privatestaticboolean hasNextPage(int currentPage, 1 wB2:o<
HA W57N
int totalPage){ xXn2M*g
return currentPage == totalPage || totalPage == y`Km96Ui
Y KWtsy
0 ? false : true; <QZ X""
} PS3%V_2
|\iJ6m;a
3,4m|Z2)
} fx`oe
BjsF5~+\
?PSVVUq,Z
jZLD^@AP
1Z| {3W
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。 g W(7jFl
nD/;
Gq
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 nW7Ew<`Q
/+{]?y,
做法如下: ]v6s](CE
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 [H&Z /.{F
|uRZT3bGyj
的信息,和一个结果集List: u{dI[?@
java代码: 3El5g0'G
B9(e"cMm
.6xIg+
/*Created on 2005-6-13*/ bX*c-r:
package com.adt.bo; oA'LQ
p?qW;1
import java.util.List; 3Sclr/t
VGtKW kVH
import org.flyware.util.page.Page; jUg.Y98
EXD Qr'"
/** i!+Wv-
* @author Joa 6l|,J`G
*/ Sx|)GTJJ|-
publicclass Result { )Fw{|7@N
xKW`m
private Page page; [>y 0Xf9^
bQelU
private List content; Se>"=[=
N@>o:(08
/** w,qYT-R
* The default constructor 1`z^Xk8vt
*/ g Xi&
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public Result(){ ^KO=8m( )J
super(); Jkq? wpYp
} Q@"mL
5(V'<
/** O!=ae|
* The constructor using fields Fy'/8Yv#L
* ?O!'ZZX
* @param page '}|sRuftb
* @param content `PVr;&
*/ 9;B6<`e/U
public Result(Page page, List content){ eTrIN,4
this.page = page; G<f"_NT
this.content = content; %@9pn1,
} 3$Y(swc
,j|9Bs
/** JVx
,1lth
* @return Returns the content. C%)Xz
*/ mx:) &1
publicList getContent(){ B]-~hP
return content; )of?!>'S[
} Zz@0Oj!`
E"{2R>mU~
/** nC;2wQ6aO
* @return Returns the page. Pm*N!:u
*/ B}y`E
<
public Page getPage(){ (ev(~Wc
return page; alB[/.1
} vsU1Lzna6@
(g>>
/** +>,4d
* @param content _Uxt9 X
* The content to set. FBCi,_
\4
*/ ,b/qcu_|-
public void setContent(List content){ O^W.5SaR
this.content = content; D3BNA]P\2@
} f6d:5
X_
n,+/%IZ
/** `*`@r o
* @param page Np?%pB!Q
* The page to set. 6)B6c. 5o
*/ $%ts#56*
publicvoid setPage(Page page){ I8RPW:B;B
this.page = page; %1Pn;bUU!
} !L)~*!+Gf
} as%ab[ fX
?9)-?tZ^Q
wh~g{(Xvq
.7"]/9oB
|z`kFil%
2. 编写业务逻辑接口,并实现它(UserManager, Eoo[)V#x{
v|r=}`k=
UserManagerImpl) viP.G/(\]
java代码: jZX2)# a!
hCcAAF*I;5
#ARQB2V
/*Created on 2005-7-15*/ V&75n.L
package com.adt.service; j~ )GZV
uR:@7n
import net.sf.hibernate.HibernateException; @},25"x)
Q{~ WWv
import org.flyware.util.page.Page; vA r
fsgk
=d{B.BP(
import com.adt.bo.Result; 9
Z5!3
$%3"@$
/** ? !dy
* @author Joa DnZkZ;E/
*/ s$,gM,|cK
publicinterface UserManager { !M&Qca2
.P|_C.3-l
public Result listUser(Page page)throws 5/ee&sJR
yX'f"*
HibernateException; uV@#;c4
`~hB-Z5dI
} /7)l 22<
L/U^1=Wi*O
\:To>A32
dV( "g],
$z>L $,c>
java代码: l|z0aF;z
1zDat@<H
zP8a=Iv
/*Created on 2005-7-15*/ nSM8o<)H
package com.adt.service.impl; %rmn+L),;
U>,E]'
import java.util.List; ka^sOC+Y
K9*vWoP'
import net.sf.hibernate.HibernateException; ^4\hZ
8-2e4^
g(
import org.flyware.util.page.Page; yyj?hR@rZ
import org.flyware.util.page.PageUtil; w4m)lQM
<h*r
import com.adt.bo.Result; DLWG0$#!
import com.adt.dao.UserDAO; zv^km5by
import com.adt.exception.ObjectNotFoundException; DhVF^=x$
import com.adt.service.UserManager; R@+%~"Z
gNsas:iGM
/** / mM# nS
* @author Joa o<Esh;;*nm
*/ -Dx_:k|k
publicclass UserManagerImpl implements UserManager { %l#i9$s
T;f`ND2fY
private UserDAO userDAO; 94>EA/+Ek
cQ?eL,z
/** tTMYqgzUk
* @param userDAO The userDAO to set. O)$rC
*/ N}j]S{j}'
publicvoid setUserDAO(UserDAO userDAO){ -8r';zR
this.userDAO = userDAO; 8$+mST'4N
} ~^{jfHTlv
5-3.7CO$
/* (non-Javadoc) #s\HiO$BT
* @see com.adt.service.UserManager#listUser RWe$ZZSz!
P0B`H7D
(org.flyware.util.page.Page) R7q\^Yzo
*/
vG{+}o#
public Result listUser(Page page)throws co93}A,k
&tAhRMa
HibernateException, ObjectNotFoundException { vpS&w
int totalRecords = userDAO.getUserCount(); f6I$d<
if(totalRecords == 0) E=H>|FgS
throw new ObjectNotFoundException b.LMJ'1
&zxqVI$4
("userNotExist"); / bxu{|.
page = PageUtil.createPage(page, totalRecords); IpJMq^Z
List users = userDAO.getUserByPage(page); klwC.=?(j"
returnnew Result(page, users); PQkFzyk
} 6ka,
FjJ\
4dEfXrMf
} {CO]wqEj
-kGwbV}
qy9RYIfZ
@d+NeS
,EE,W0/zzM
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 YR 5C`o
P1r)n{;
询,接下来编写UserDAO的代码: 6D=9J%;
3. UserDAO 和 UserDAOImpl: u%o]r9xl'
java代码: d;4LHQ0yU
tRl01&0S
Y#/mE!&
/*Created on 2005-7-15*/ Rz #&v
package com.adt.dao; ~yGD("X
.J0Tn,m
import java.util.List; XTibx;yd<
uPmK:9]3R
import org.flyware.util.page.Page; gPW% *|D,
[1LlzCAFBw
import net.sf.hibernate.HibernateException; pM|m*k
DR%16y<h
/** WRBCNra
* @author Joa DV8b<)
*/ +2KYtyI
publicinterface UserDAO extends BaseDAO { Ao0p=@Y
M_OvIU(E
publicList getUserByName(String name)throws cbton<r~
?ufX3yia
HibernateException; !Lu noC>B
+nz6+{li\
publicint getUserCount()throws HibernateException; 61[ 8I},V
+.EP_2f9
publicList getUserByPage(Page page)throws Az`c ?
W%
K1gZ>FEY|N
HibernateException; M2$.Yom[
\~(scz$
} Asy&X
"CX@a"
uZg[PS=@!X
L&I8lG
I*SrKZb
java代码: :rBPgrt
U5iyvU=UG
C8xx R~mq
/*Created on 2005-7-15*/ j&
H4L
package com.adt.dao.impl; v!>(1ROQ.=
or8`.hEHI
import java.util.List; *%nV<}e^_=
xpO'.xEs
import org.flyware.util.page.Page; TEzMFu+V
9sgyg3fv>5
import net.sf.hibernate.HibernateException; &(Yv&jX
import net.sf.hibernate.Query; SyB2A\A
Fad.!%[
import com.adt.dao.UserDAO; r*r3QsO
js$L<^7
/** _, ki/7{
* @author Joa xsO
"H8
*/ FJ/c(K
public class UserDAOImpl extends BaseDAOHibernateImpl wDv G5
pz hPEp;
implements UserDAO { kA"|PtrW
j@Ta\a-,x
/* (non-Javadoc) _oILZ,
* @see com.adt.dao.UserDAO#getUserByName r'bPSu,
<\fB+ AZ
(java.lang.String) ,\Q^[e!m~
*/ ROWI.|
publicList getUserByName(String name)throws B1U<m=Y
sU=7)*$
HibernateException { ZHN@&Gg6)
String querySentence = "FROM user in class Zw`9B
\se
/2l
com.adt.po.User WHERE user.name=:name"; MmbS["A
Query query = getSession().createQuery Y6Mp[=
!1b4q/
(querySentence); 5fT"`FL?
query.setParameter("name", name); auai@)v6
return query.list(); ;usR=i36b
} blk4@pg
+W7#G `>
/* (non-Javadoc) <b,oF]+;z
* @see com.adt.dao.UserDAO#getUserCount() =-m"y~{>3
*/ "C/X#y
publicint getUserCount()throws HibernateException { &Rp/y%9
int count = 0; )ZQ>h{}D
String querySentence = "SELECT count(*) FROM gic!yhsS_
T!yI+<
user in class com.adt.po.User"; \,ko'48@
Query query = getSession().createQuery B*3<(eI
,pHQv(K/
(querySentence); %@~;PS3kd
count = ((Integer)query.iterate().next l2*o@&.
'O+)[D
()).intValue(); e*!0|#-
return count; %S$+3q%F
} L>>RboR}
Tp[-,3L
/* (non-Javadoc) {@7xOOAw
* @see com.adt.dao.UserDAO#getUserByPage /)-OK7x
y(fJ{k
(org.flyware.util.page.Page) 2gM/".|{
*/ tYk!Y/O}
publicList getUserByPage(Page page)throws GpZ}xY'|w,
t8?$q})RL
HibernateException { ^D5+S`V
String querySentence = "FROM user in class tZL {;@
Oj,v88=
com.adt.po.User"; Q&@e,7]V+
Query query = getSession().createQuery zAkF:^#Y
O,[9E
(querySentence); >oGs0mej
query.setFirstResult(page.getBeginIndex()) B'D\l\w
.setMaxResults(page.getEveryPage()); Gv+$7{
return query.list(); `bJ?8~ 8*
} k
E},>+W+
NE)Yd7m-
} 5I6u 2k3
|\<L7|hb9
r^v1_u,1I
crbph.0
/=K(5Xd
至此,一个完整的分页程序完成。前台的只需要调用 G&z^AV
q\n,/#'i~
userManager.listUser(page)即可得到一个Page对象和结果集对象 kc7,F2=F
Kk\TW1w3
的综合体,而传入的参数page对象则可以由前台传入,如果用 n|N?[)^k
o FS2*u
webwork,甚至可以直接在配置文件中指定。 &~KAZ}xu
0Lx,qZ'
下面给出一个webwork调用示例: R^?9V=Y<T
java代码: hCPyCq]
R
KXhD PA
>n"4M~I
/*Created on 2005-6-17*/ |r+w(TG
package com.adt.action.user; `Iqh\oY8-
s`2q(`}
import java.util.List; ^:u-wr8?{
:LxsiDrF[
import org.apache.commons.logging.Log; EpCF/i?9:
import org.apache.commons.logging.LogFactory; fda)t1u\8
import org.flyware.util.page.Page; j_{f(.5
qHl>d*IZ
import com.adt.bo.Result; NA!?.zn
import com.adt.service.UserService; eqSCE6r9x
import com.opensymphony.xwork.Action; qx1+'
^e{]WH?
/** N#p%^GH
* @author Joa CxD=8X9m
*/ fl}!V4
publicclass ListUser implementsAction{ ZKTY1JW_
yXT.]%)
privatestaticfinal Log logger = LogFactory.getLog JI[{n~bhGD
z)ndj
1,#)
(ListUser.class); Sfa;;7W@R
p|>m 2(|
private UserService userService; ;Sl%I+?
KsSIX
private Page page; HJ_8 `( '
"SA*
privateList users; pCC3r t(
adWH';Q:
/* Ke^9R-jP
* (non-Javadoc) #+ Y%Bxf
* Jbn^G7vH<6
* @see com.opensymphony.xwork.Action#execute() D!V~g72j
*/ `4-N@h
publicString execute()throwsException{ RpwDOG
Result result = userService.listUser(page); eX$RD9
H
page = result.getPage(); T,9pd;k
users = result.getContent(); AD~_n^
return SUCCESS; B8~bx%)3T
} tTbfyI
UCo`l~K)qg
/** Z]XjN@j"
* @return Returns the page. ~7wLnB
*/ 8[H bg
public Page getPage(){ :;jRAjq"
return page; i8A-h6E
} jbe_r<{
/5X_gjOL,
/** ct@3]
* @return Returns the users. XzBlT( `w
*/ #sE:xIR
publicList getUsers(){ E(_lm&,4+
return users; 84<zTmm
} aA]wFZ
:W#?U yo
/** (QS 0
* @param page {s0!hp
* The page to set. a1shP};pK
*/ OkMAqS
publicvoid setPage(Page page){ 7ufTmz#j<
this.page = page; `SA1V),~
} P2F8[o!<
_:>t$*
_
/** Rh%A^j@
* @param users L]q%;u]8!
* The users to set. P8[k1"c!
*/ dKY#Tl]
publicvoid setUsers(List users){ ?e\u_3-9
this.users = users; PPde!}T$
} p]qz+Z/
kDG?/j90D
/** /!sGO:
* @param userService OBf$Z"i
* The userService to set. a@-bw4SD
*/ T^ - - :1
publicvoid setUserService(UserService userService){ %{jL+4veoL
this.userService = userService; U,8mYv2|
} BKV:U\QZ
} !AGoI7W}
Q$Rp?o&
:o:Z
1.5R`vKn]
:jJ0 +Q
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, ,u9>c*Ss\
==S^IBG
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 L)
UCVm
2t?Vl%<
么只需要: =7EkN% V:{
java代码: )6%a9&~H
ts;^,|h
B%5"B} nG
<?xml version="1.0"?> `~D{]'j
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork 2Z ?l,M~
$&Z<4:Flc
1.0//EN" "http://www.opensymphony.com/xwork/xwork- j8%Y[:~D
nUK;M[
1.0.dtd"> ?@<Tzk]a.
*J{E1])<a
<xwork> )x35
u
$B24Cy.
<package name="user" extends="webwork- :m36{#
!$#5E1:\
interceptors"> 1Beh&pl^
$W9dUR0
<!-- The default interceptor stack name Ya-GDB;L
:\C/mT3xL)
--> h+S]C#X,}
<default-interceptor-ref CF
v ]wS
1~E;@eK'
name="myDefaultWebStack"/> >DN^',FEm
{;Oj
<action name="listUser" ZZ/k7(8
Y~w1_>b
class="com.adt.action.user.ListUser"> :
@$5M
<param $LG.rJ/*
ENI|e,'[
name="page.everyPage">10</param> |XMWi/p
<result Ec^2tx"=
b}*q*Bq
name="success">/user/user_list.jsp</result> 5=Y(.}6
</action> E(&zH;?_
pD }b $
</package> TmK8z
?A04qk
</xwork> qE8Di\?
$ab{GxmX'4
SjIDzNI5
z2Z}mktP
.EvP%A
m
B1]FB|0's
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 =1xVw5^F
nU 0##
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。
@H^\PH?pp
x=X&b%09
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 r?dkE=B
bR$5G
J%
ZM
V
F5OQM?J
0_,un^
我写的一个用于分页的类,用了泛型了,hoho {bG. X?b
xk3)#*
java代码: qQ1D }c@
R^]a<g,
P@x@5uC2
package com.intokr.util; K)}Vr8,V
# %'%LY=
import java.util.List; RRzLQ7J
t~.^92]s|
/** ad9u;uS
* 用于分页的类<br> =LEzcq>XO
* 可以用于传递查询的结果也可以用于传送查询的参数<br> ;bL?uL
* s.XxYXR\
* @version 0.01 ~}SQLYy7Z
* @author cheng Yv2L0bUo:
*/ >h~>7i(A
public class Paginator<E> { {hm-0Q
privateint count = 0; // 总记录数 *~w?@,}
privateint p = 1; // 页编号 JvaHH!>d/
privateint num = 20; // 每页的记录数 ]mjKF\
privateList<E> results = null; // 结果 .'4@Yp{=
A7eYKo
q
/** [?(qhp!
* 结果总数 #a'CoJs
*/ 7M_GGjP
publicint getCount(){ vV*/"'>
return count; JeAyT48!M
} wRq
f'
:c`djM^ll
publicvoid setCount(int count){ XhN?E-WywQ
this.count = count; {7q8@`Oa
} r 5+ MjR
%o`Cp64`Q
/** #qJ6iA6{
* 本结果所在的页码,从1开始 6Q&i=!fQ
* &4)PW\ioY
* @return Returns the pageNo. 0UGAc]!/RZ
*/ 238z'I+$G/
publicint getP(){ VTi;y{
return p; @&9<)1F
} 84s:cO
2P{! n#"
/** \lyHQ-gWhc
* if(p<=0) p=1 = N:5#A
* . TNJuuO
* @param p Zc*#LsQh.`
*/ ?+$EPaC2
publicvoid setP(int p){ $N|Spp0
if(p <= 0) RLGIST`
p = 1; zE7)4!
this.p = p; =,08D^ xY
} Tc|+:Usy
%;J$ h^
/** N]GF>kf:
* 每页记录数量 B0gs<E
*/ n:Dr< q.
publicint getNum(){ zP/SDW
return num; s8k4e6ak
} XHY,;4
LrV|Y~
/** "\M3||.!
* if(num<1) num=1 s5X51#J#~
*/ En0hjXa
publicvoid setNum(int num){ ENf(E9O
if(num < 1) [kPl7[OL
num = 1; h9~oS/%:
this.num = num; SW Hi iF@
} P{,=a]x,mz
W=,]#Z+M;
/** QR$m i1Vv\
* 获得总页数 ,{Z!T5 |
*/ }q?q)cG
publicint getPageNum(){ !{ORFd
return(count - 1) / num + 1; Ihl]"76q/
} w"
A{R
@^HZTuP2;
/** u#3Cst8Y
* 获得本页的开始编号,为 (p-1)*num+1 nNRc@9Lt
*/ 2V$YZSw6q
publicint getStart(){ WTZuf9:
return(p - 1) * num + 1; |s!n7%|,7
} }IKU^0M9<T
5g 2:o^
/** l585L3i
* @return Returns the results. w}x&wWM
*/ [Fr <tKtB
publicList<E> getResults(){ t<+gyAW
return results; -?ebkHe
} i\RB KF
T`Xz*\}Zb
public void setResults(List<E> results){ >~T2MlRux
this.results = results; MnptC 1N
} yeV|j\TJI.
?jnbm'~S
public String toString(){ \K:?#07Wj4
StringBuilder buff = new StringBuilder z~;@Mo"*f
+@\=v}:
F
(); IY|>'}UU#
buff.append("{"); 3[%n@i4H|
buff.append("count:").append(count); .?r}3Ch
buff.append(",p:").append(p); N$cAX^~
buff.append(",nump:").append(num); q)tNH/
buff.append(",results:").append S#\Cyn2(t
59(} D'lw>
(results); >< Qp%yT
buff.append("}"); IpVtbDW
return buff.toString(); U@)WTH6d
} 7#9fcfL
~8[`(/hj
} j8ac8J,}c
uecjR8\e
Z'c9xvy5