Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 1t:Q_j0Ym
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 )JDs\fUE
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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 RY]#<9>M
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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 JmF l|n/H
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分页支持类: #ZJ _T`l
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java代码: gy,ht3
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package com.javaeye.common.util; In:9\7~jC
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import java.util.List; X\`_3=
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publicclass PaginationSupport { :Ux?,
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publicfinalstaticint PAGESIZE = 30; V@B__`y7
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privateint pageSize = PAGESIZE; HKU~UTRnZ
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privateList items; %z/hf
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privateint totalCount; zjJ *n8l
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privateint[] indexes = newint[0]; j5K]CTz#
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privateint startIndex = 0; B( ]M&
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public PaginationSupport(List items, int .\[`B.Q
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totalCount){ YNLV9.P6
setPageSize(PAGESIZE); un)4eo!7
setTotalCount(totalCount); %j:]^vqFA
setItems(items); aO]ZZleNS
setStartIndex(0); Z8# (kmBdB
} 1e(E:_t
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public PaginationSupport(List items, int H;?{BV
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l
totalCount, int startIndex){ )LdP5z-
setPageSize(PAGESIZE); %@wJ`F2a_
setTotalCount(totalCount); )jU)_To
setItems(items); k&&2Tq
setStartIndex(startIndex); `s"'r !
} ~?D4[D|sB
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public PaginationSupport(List items, int yL%K4$z
y-T| #
totalCount, int pageSize, int startIndex){ ^M3~^lV
setPageSize(pageSize); )`SES."
setTotalCount(totalCount); !Nu<xq@!
setItems(items); ?p9VO.^5
setStartIndex(startIndex); fdxLAC
} 1QqYQafA
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publicList getItems(){ +vYoB$!
return items; e&simX;W
} *v;!-F&8>
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publicvoid setItems(List items){ qHsUP;7
this.items = items; k>F'ypm
} bBu,#Mc
@PN#p"KaT
publicint getPageSize(){ -u&6X,Oq\u
return pageSize; 9:fOYT$8
} B.wYHNNV
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publicvoid setPageSize(int pageSize){ c;%_EN%
this.pageSize = pageSize; wmk
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} >NqYyW,%
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publicint getTotalCount(){ Vx(B{5>Vu
return totalCount; p`mS[bxv!
} ~3UQ|j
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publicvoid setTotalCount(int totalCount){ #,S0HDDHn
if(totalCount > 0){ P::TO-C
this.totalCount = totalCount; 9iXeBC
int count = totalCount / G3{Q"^S"
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pageSize; /d0K7F
if(totalCount % pageSize > 0) M8INk,si
count++; \[BK1JP
indexes = newint[count]; w<C#Bka
for(int i = 0; i < count; i++){ W@ T~ly;e*
indexes = pageSize * _6_IP0;
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i; kv8Fko
} DamCF
}else{ r^h4z`:L
this.totalCount = 0; x N=i]~
} ]Gpxhg
} Yb:\a/ y
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publicint[] getIndexes(){ E>&n.%
return indexes; %dJX-sm@
} 7x#Ckep:I
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publicvoid setIndexes(int[] indexes){ <!L>Exh&r
this.indexes = indexes; bQE};wM,
} k xP-,MD
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publicint getStartIndex(){ (H)2s Y
return startIndex; 4 d;|sI@
} VK}fsOnj0
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publicvoid setStartIndex(int startIndex){ I{
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if(totalCount <= 0) )_1zRT| 9
this.startIndex = 0; =2Bg9!zW>
elseif(startIndex >= totalCount) JQ}$Aqk
this.startIndex = indexes dODt(J}%
#@^t;)|
[indexes.length - 1]; Q&MZN);.
elseif(startIndex < 0) 0*%Z's\M"
this.startIndex = 0; iDMJicW!+F
else{ OH;b"]
this.startIndex = indexes nNrPHNfqD
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[startIndex / pageSize]; W"):-Wq
} !O-T0O
} I'PeN0T
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publicint getNextIndex(){ ;} und*q
int nextIndex = getStartIndex() + kdCUORMK
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pageSize; D|@/yDQ
if(nextIndex >= totalCount) JmPHAUd
return getStartIndex(); /3A^I{e74
else HkQ*y$$
return nextIndex; W`K7 QWV4
} ;epV<{e$q4
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publicint getPreviousIndex(){ dA@'b5N{"
int previousIndex = getStartIndex() - _Xn qb+
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pageSize; ]GN7+8l
if(previousIndex < 0) sW)Zi
return0; ld3-C55
else -M%_\;"de
return previousIndex; [`p=(/I&L
} MxWy*|J}
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} RMd[Yr2e
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抽象业务类 ELBa}h;
java代码: ,z3{u162
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/** g) p,5BADm
* Created on 2005-7-12 SxdE?uCUS
*/ (ohq0Y
package com.javaeye.common.business; lrnyk(M}Q.
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import java.io.Serializable; U"q/rcA
import java.util.List; )E6;-rD0^+
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import org.hibernate.Criteria; (rkyW z
import org.hibernate.HibernateException; O<96/a'
import org.hibernate.Session; RRmLd/(
import org.hibernate.criterion.DetachedCriteria; T?:glp[4I
import org.hibernate.criterion.Projections; ZN!4;
import _u{c4U0,
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org.springframework.orm.hibernate3.HibernateCallback; P8^hBv*
import oo.! .Kv
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org.springframework.orm.hibernate3.support.HibernateDaoS AFc$%\s4
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upport; p[<Dk$7K
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import com.javaeye.common.util.PaginationSupport; 0GB:GBhZ
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public abstract class AbstractManager extends GytXFL3`:
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HibernateDaoSupport { /rq VB|M
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privateboolean cacheQueries = false; m>4ahue$
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privateString queryCacheRegion; :!5IW?2
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publicvoid setCacheQueries(boolean Lg~B'd8m
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cacheQueries){ =
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this.cacheQueries = cacheQueries;
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} vFE;D@bz:
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publicvoid setQueryCacheRegion(String $-#Yl&?z9
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queryCacheRegion){ S:TgFt0
this.queryCacheRegion = e*@{%S
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queryCacheRegion; ##@$|6
} ?CC"Yij
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publicvoid save(finalObject entity){ %^I88,$&L
getHibernateTemplate().save(entity); ]l'Y'z,}
} cgl*t+o&
9AxCiT.
publicvoid persist(finalObject entity){ w=^`w:5X
getHibernateTemplate().save(entity); w QNxL5B
} Bn61AFy`
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publicvoid update(finalObject entity){ AZa6Cw
getHibernateTemplate().update(entity); F%i^XA]a*
} |tv"B@`
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publicvoid delete(finalObject entity){ @O@GRq&V
getHibernateTemplate().delete(entity); z "+Mrew
} Q3|T':l4
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publicObject load(finalClass entity, NZ/yBOD(
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finalSerializable id){ 9cEv&3
return getHibernateTemplate().load F>]m 3(
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(entity, id); )RO<o O
} ~4s'0 w^
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publicObject get(finalClass entity, cx}Q2S
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finalSerializable id){ 4m*M,# mV
return getHibernateTemplate().get GN!qyT
F)+{AQL
(entity, id); d}JP!xf%
} 6KVnnK
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publicList findAll(finalClass entity){ mp9{m`Jb*
return getHibernateTemplate().find("from G:pEE:W[
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" + entity.getName()); '@jXbN
} +hE(Ra#
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publicList findByNamedQuery(finalString ax{ ;:fW
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namedQuery){ y`$Q\}fS
return getHibernateTemplate br0++}vwL
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().findByNamedQuery(namedQuery); J|X
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} ~(pmLZ<GW}
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publicList findByNamedQuery(finalString query, "Kc>dJ@W
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finalObject parameter){ $KLD2BAL
return getHibernateTemplate em\ 9'L^
j'aHF#_
().findByNamedQuery(query, parameter); g8w2Vz2/
} 81hbk((
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publicList findByNamedQuery(finalString query, -jn WZ5.
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finalObject[] parameters){ : C b&v07
return getHibernateTemplate o99pHW(E
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().findByNamedQuery(query, parameters); c\ia6[3sX
} ?Q-h n:F)
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publicList find(finalString query){ NM0tp )h
return getHibernateTemplate().find YKbaf(K)9
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(query); z81esXl
} &q`q4g&7
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publicList find(finalString query, finalObject ?x+Z)`w_
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parameter){ K]U;?h&CZc
return getHibernateTemplate().find xS7$%w['
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(query, parameter); eL4NB$Fb
} ?d4m!HgR
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public PaginationSupport findPageByCriteria >yXN,5d[
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(final DetachedCriteria detachedCriteria){ :> & fV
return findPageByCriteria /
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); <,AS8^$X[
} %0 #XPc("
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public PaginationSupport findPageByCriteria rJa$9B*^
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(final DetachedCriteria detachedCriteria, finalint `\X+ Ud|
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startIndex){ `+t.!tv!
return findPageByCriteria 49d@!
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(detachedCriteria, PaginationSupport.PAGESIZE, xr7+$:>a
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startIndex); ?=VOD #)
} W5^.-B,(K
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public PaginationSupport findPageByCriteria G&;j6<h l
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(final DetachedCriteria detachedCriteria, finalint
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pageSize, X[2[!)Rk
finalint startIndex){ \m=?xb8
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return(PaginationSupport) A~Xq,BxCV
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getHibernateTemplate().execute(new HibernateCallback(){ N)S!7%ne
publicObject doInHibernate kD) $2I?
# wc \T
(Session session)throws HibernateException { ?0_7?yTR/
Criteria criteria = ;.wX@
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detachedCriteria.getExecutableCriteria(session); $
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int totalCount = DMF
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((Integer) criteria.setProjection(Projections.rowCount ^`SA'F,
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()).uniqueResult()).intValue(); Z+pom7A"E
criteria.setProjection mp~{W
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(null); NNG}M(/V
List items = aS|wpm)K>8
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criteria.setFirstResult(startIndex).setMaxResults +%N
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XJ!(F#zc
(pageSize).list(); 1Uf*^WW4
PaginationSupport ps = k>E`s<3
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new PaginationSupport(items, totalCount, pageSize, $KjTa#[RX7
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startIndex); Q,Z*8FH=
return ps; )'Wb&A'
} h{lDxOH*
}, true); .bf<<+'o
} ,}xbAA#
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public List findAllByCriteria(final *m+5Pr`7
6AN)vs}
DetachedCriteria detachedCriteria){ Je4Z(kj 0
return(List) getHibernateTemplate Pw@olG'Ah
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().execute(new HibernateCallback(){ Lc<eRVNd,
publicObject doInHibernate oKFT?"[X
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(Session session)throws HibernateException { @\(v X ]
Criteria criteria = ? 81X
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detachedCriteria.getExecutableCriteria(session); 3Dm8[o$Z
return criteria.list(); nY `2uN~9
} >+cVs:
}, true); <Y'>F!?#
} A1cb"N^
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public int getCountByCriteria(final rFJ[dz
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DetachedCriteria detachedCriteria){ Z\>, ),O
Integer count = (Integer) K&A;Z>l,v5
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getHibernateTemplate().execute(new HibernateCallback(){ h3u1K>R)
publicObject doInHibernate z&nZ<ih
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(Session session)throws HibernateException { @?B6aD|jE
Criteria criteria = j?(!^ _!m
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detachedCriteria.getExecutableCriteria(session); W^g[L:s
return XOb}<y)r~
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criteria.setProjection(Projections.rowCount wpPn}[a
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()).uniqueResult(); j kn^Z":
} 96|[}:+$&:
}, true); Edt}",s7
return count.intValue(); ?Z %:
} ]j.k?P$U}
} RU!?-#*
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用户在web层构造查询条件detachedCriteria,和可选的 A[/I#Im7
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 lxb 8xY
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PaginationSupport的实例ps。 o<VP'F{p
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ps.getItems()得到已分页好的结果集 (6xDu.u?A
ps.getIndexes()得到分页索引的数组 delf
]
ps.getTotalCount()得到总结果数 -l*A
ps.getStartIndex()当前分页索引 F&@ |M(
ps.getNextIndex()下一页索引 E8[XG2ye
ps.getPreviousIndex()上一页索引 {7#03 k
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 ( tn<
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,尤其是上面的示例代码,让我着实觉得该对我原来的分页查询做 .hz2&9Ow
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一下代码重构了。 <'*4j\*
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我把原本我的做法也提供出来供大家讨论吧: c f*zejbw
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首先,为了实现分页查询,我封装了一个Page类: YN#XmX%
java代码: ba&o;BLUy
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/*Created on 2005-4-14*/ &va*IR
package org.flyware.util.page; _t.FL@3e
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"
/** gM, &Spn
* @author Joa pG28M]\
* nEVbfNo0
*/ Ruj.J,
publicclass Page { U"x~Jb3]O
Wm>b3:
/** imply if the page has previous page */ zPBfiK_hV
privateboolean hasPrePage; "^"'uO$
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/** imply if the page has next page */ ysth{[<5F3
privateboolean hasNextPage; 9HKf^+';n
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/** the number of every page */ G+C}<S}
privateint everyPage; "WP% REE!
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/** the total page number */ j0?>w{e
privateint totalPage; T9y768%
MCd F!{
/** the number of current page */ =LqL@5Xr
privateint currentPage; ||f vKyKW>
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/** the begin index of the records by the current MLeX;He
/&QQ p3
query */ nrbazyKm
privateint beginIndex; kYtHX~@
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ex0oAt^
/** The default constructor */ u#!GMZJN
public Page(){ khS/'b
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} <vLdBfw&N
/pU|ZA.z'2
/** construct the page by everyPage 6d};|#}
* @param everyPage } bCK
* */ AtT"RG-6
public Page(int everyPage){ -[<vYxX:h:
this.everyPage = everyPage; gE1|lY$NL
} ~K%k
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*bU% @O
/** The whole constructor */ >*{:l,LH
public Page(boolean hasPrePage, boolean hasNextPage, )5'rw<:="
{9Xm<}%u]]
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int everyPage, int totalPage, p&QmIX]BZ
int currentPage, int beginIndex){ /Go>5B>
this.hasPrePage = hasPrePage; KZZOi:
this.hasNextPage = hasNextPage; 5U3qr*/ ;m
this.everyPage = everyPage; D| [/>x
this.totalPage = totalPage; B3eNFS
this.currentPage = currentPage; zF=#6
this.beginIndex = beginIndex; Fdr*xHx$P
}
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/** $\0TD7p
* @return 4p?+LdL
* Returns the beginIndex. R/Tj^lM
*/ P:>'
publicint getBeginIndex(){ G I&qwA
return beginIndex; F68},N>vr@
} {uEu>D$8
f 5mY;z"
/** =jsx(3V
* @param beginIndex $ 9S>I'
* The beginIndex to set. ]!]`~ Z/
*/ FK-}i|di
publicvoid setBeginIndex(int beginIndex){ f%vHx,
this.beginIndex = beginIndex; ;_>s0rUV
} 7E;>E9 '
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/** L-`(!j
* @return A J<iM)l|
* Returns the currentPage. ~o}moE/
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*/ O)Xd3w'
publicint getCurrentPage(){ jQY>9+t
return currentPage; yBr$ 0$
} >oVc5}
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/** t^`<*H
* @param currentPage zf M<x,XdY
* The currentPage to set. 0Ei\VVK>
*/ eUX@9eML
publicvoid setCurrentPage(int currentPage){ OJnPP>
this.currentPage = currentPage; J&
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} #k"1wSx16
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/** ~+sne7
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* @return c2tEz&=G
* Returns the everyPage. e}{8a9J<%_
*/ ~5-~q0Ge
publicint getEveryPage(){ (2\l i{$e
return everyPage; Yt\E/*%
} ( 1QdZD|
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/** rU/-Wq`B
* @param everyPage DR.3
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* The everyPage to set. uYG #c(lc
*/ u.ULS3`C/X
publicvoid setEveryPage(int everyPage){ @t{{Q1
this.everyPage = everyPage; WyKUvVi
} &6|6J1c8
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/** jldcvW
* @return nOA,x
* Returns the hasNextPage. ` 4s#5g
*/ 5Ws:Ei{R
publicboolean getHasNextPage(){ d +*T@k]>M
return hasNextPage; }w|=c>'_}
} O3slabE#
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/**
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* @param hasNextPage -o!saX<
* The hasNextPage to set. $6Q2)^LJ
*/ +iZ@.LI
publicvoid setHasNextPage(boolean hasNextPage){ ND)M3qp2(
this.hasNextPage = hasNextPage; BP7<^`i&
} "GIg|3
rm7*l<v6
/** W#oEF/G
* @return @E&X&F%
* Returns the hasPrePage. =6"hj,[Q
*/ (AyRs7Dkn
publicboolean getHasPrePage(){ vl#V-UW$4P
return hasPrePage; r`mzsO-'
} |zr)hC
J\Oc]gi\L
/** .PA?N{z
* @param hasPrePage !T&u2=`D
* The hasPrePage to set. f6/\JVi)-
*/ X~<>K/}u5
publicvoid setHasPrePage(boolean hasPrePage){ `"bRjC"f]
this.hasPrePage = hasPrePage; \a~;8):q=i
} 4F 6ju6w
+wPvQKVfI
/** e2VL/>y`
* @return Returns the totalPage. ni 02N3R
* fu7[8R"{
*/ m8j#{[NE
publicint getTotalPage(){ <T=o]M$
return totalPage; }!J/ 9WKgU
} Q%b46"
'
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/** z;@S_0M,Z
* @param totalPage _oyL*Cb
* The totalPage to set. hGaYQgGq
*/ !UPAEA
publicvoid setTotalPage(int totalPage){ 5"Xo R)
this.totalPage = totalPage; :;gwdZ
} )I0g&e^Tzy
=}1~~
} *TMM:w|1
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g]hn@{[
^LAS9K1.
4 9+}OIX
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 9ixnf=$Jp
C8%nBa/
个PageUtil,负责对Page对象进行构造: kQ:>j.^e
java代码: e1Z;\U$&.
h: (l+jr
tZ6v@W
/*Created on 2005-4-14*/ e[Ul"pMvS`
package org.flyware.util.page; zJym`NF
#on fac- 3
import org.apache.commons.logging.Log; _M[[o5{
import org.apache.commons.logging.LogFactory; 085 ^!AZ
i=+<7]Q
/** "Mu$3w
* @author Joa RI].LB_
* "q#g/T
*/ ckkM)|kK
publicclass PageUtil { i2 Iu2
/-} p7AM
privatestaticfinal Log logger = LogFactory.getLog )}Mt'd
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(PageUtil.class); 1F%*k &R
nHL>}Yg
/** doUqUak
* Use the origin page to create a new page \~m%4kzG8J
* @param page gbi~!S-
* @param totalRecords fxCPGj
* @return ?>Ci`XlLr
*/ J*kzJ{vwy*
publicstatic Page createPage(Page page, int nT6iS}h
v?iH}7zb%Q
totalRecords){ EwJn1Mvq
return createPage(page.getEveryPage(), l<:)rg^,
t@mw f3,
page.getCurrentPage(), totalRecords); +]2~@=<@
} i_9/!D
h3ZL0Fi*
/** 9U%}"uE
* the basic page utils not including exception eT
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handler e(5Px!B
* @param everyPage vG=$UUh@~
* @param currentPage
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* @param totalRecords PbC>v
* @return page U\plt%2m>
*/ ~]s"PV:|
publicstatic Page createPage(int everyPage, int T_
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currentPage, int totalRecords){ >TVd*S
everyPage = getEveryPage(everyPage); dQoMAsxzM
currentPage = getCurrentPage(currentPage); =Qq^=3@h
int beginIndex = getBeginIndex(everyPage, eyp\h8!u_
[WSIC *|;
currentPage); 2:0Y'\nn
int totalPage = getTotalPage(everyPage, 4C*=8oe_
MPw7!G(qj
totalRecords); `Y$5g~3.
boolean hasNextPage = hasNextPage(currentPage, "+C\f)
$CV'p/^En
totalPage); vWga>IGM
boolean hasPrePage = hasPrePage(currentPage); Dy'l]vN$
d|HM
returnnew Page(hasPrePage, hasNextPage, _^A
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everyPage, totalPage, {;~iq
currentPage, zIm!8a
=5#Jsn?U
beginIndex); X+BSneu
} Tj~#Xc
nWsz0v3'9
privatestaticint getEveryPage(int everyPage){ -w0>4JDs
return everyPage == 0 ? 10 : everyPage; RlL,eU$CS
} YCdxU1V
P.P>@@+d
privatestaticint getCurrentPage(int currentPage){ n#,l&Bx
return currentPage == 0 ? 1 : currentPage; kV<)>Gs
} %P6!vx:&^b
@=1``z#
privatestaticint getBeginIndex(int everyPage, int W.<<azi
I(S6DkU
currentPage){ Ku'U^=bVm:
return(currentPage - 1) * everyPage; 9D21e(7X
} 9jO+ew
w\4m-Z{
privatestaticint getTotalPage(int everyPage, int Z}f_\d'
F4{<;4N0
totalRecords){ V0(ABi:d
int totalPage = 0; %tLq&tyeY
c^k.
<EA
if(totalRecords % everyPage == 0) #{1fb%L{i
totalPage = totalRecords / everyPage; _
RYZyw
else *5)!y
d
totalPage = totalRecords / everyPage + 1 ; Uc2#so$9
&o.SmkJI
return totalPage; vL0Ol-Vt
} n5/Q)*e0'#
_%B`Y ?I`
privatestaticboolean hasPrePage(int currentPage){ [t'"4
return currentPage == 1 ? false : true; @9a=D<'>
} 7 >(ygu
N R{:4zJT
privatestaticboolean hasNextPage(int currentPage, 5K<C
a/fYD2uNo
int totalPage){ q4oZJ -`
return currentPage == totalPage || totalPage == AJu.
Y}Uw7\e
0 ? false : true; k"$V O+}m
} ^Du_e(TiyK
TH &B9
0b'R5I.M
} ,~#hHhR_
Viw3 /K
u!W00;`L
dGe
mr? ii
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。 @T"385>
?a@l.ZM*
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 ;Lu|fQ#u*
?%(*bRV -
做法如下: ,PYe7c
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 R0[Gfq9M=
Pif1sL6'
的信息,和一个结果集List: `u-Y 5mY
java代码: lRb)Tz6SE
f&'md
ZUycJ-[
/*Created on 2005-6-13*/ |wx1
[xZ
package com.adt.bo; $.Ni'U
=[kv@p
import java.util.List; (!s[~O 6
%~~Q XH\
import org.flyware.util.page.Page; _ sd?l
z5I<,[`
/** U N/.T
* @author Joa {+;8dtZ)x
*/ <,{v>vlw
publicclass Result { !k:j+h/
H UjmJu6f{
private Page page; "<n{/x(
tyh%s"
private List content; <IYt*vlm
l-&f81W
/** 7Do)++t
* The default constructor :.<&Y=^
*/ hY!G>d{J
public Result(){ F&0rI8Nr
super(); t%)L8%Jr
} /bWV`*
-}%zus5
/** -?uwlpm#
* The constructor using fields GCrN:+E0FJ
* sb1/4u/W
* @param page *;Vq0a!
* @param content *M{1RMc
*/ ~'ovJ46tx
public Result(Page page, List content){ rP'oUV_
this.page = page; zMa`olTZ
this.content = content; (/%}a`2#o
} , Le_PJY)
Th8xh=F[
/** >,DR{A2hSB
* @return Returns the content. 4AGc2e'u
*/ 8)i\d`
publicList getContent(){ m>iuy:ti
return content; vjHbg#0 %
} F?UL0Q|u v
/F\7_
/** vOqT Ld
* @return Returns the page. sIyLW
*/ '!_o`t@
public Page getPage(){ )T>a|.
return page; `p!.K9r7
} WYq, i}S
k2xjcrg
/** Iv{}U\ u
* @param content (F
@IUbnl
* The content to set. %hXa5}JL
*/ Cnn,$R=/s
public void setContent(List content){ YXmLd'F^3
this.content = content; rP*?a~<
} zNBG;\W
m8FKr/Z-
/** UOa{J|k>h
* @param page V482V#BP
* The page to set. Qc6323/"
*/ n|(Y?`(
publicvoid setPage(Page page){ d~.#K S
this.page = page; EB)0 iQ
} >:Rc%ILym
} ^D!UF(H
C3D1rS/I
r=s7be
]E,
Wt_@ vs@.O
2. 编写业务逻辑接口,并实现它(UserManager, IuRKj8J)o
,UY],;ib
UserManagerImpl) ).k=[@@V
java代码: La9dFe-uu{
*`|F?wF
4O2O0\o:
/*Created on 2005-7-15*/ Y@Ty_j~
package com.adt.service; !sUo+Y
=T9QmEBm
import net.sf.hibernate.HibernateException; K4y4!zz
x#'#
~EO-G
import org.flyware.util.page.Page; Uh*V>HA#
xqIt?v2c
import com.adt.bo.Result; `NrxoU=
!MoGdI-<r[
/** `j@2[XdHu
* @author Joa )fv0H&g
*/ 1H%LUA
publicinterface UserManager { Ow<=K:^
9=Y-w s
public Result listUser(Page page)throws _bu, 1EM
{i3]3V"Xp
HibernateException; )V} t(>V
8IbHDDS
} nCJ)=P.d
}>>BKn
7@5}WNr
EC|t4u3
L3,p8-d9Z
java代码: Fd9ypZs
Ac|IBXGa=
b v~"_)C
/*Created on 2005-7-15*/ =rGjOb3+
package com.adt.service.impl; g7rn|<6FI
_|`S9Nms
import java.util.List; C8%q?.nH=
~+7q.XL$$K
import net.sf.hibernate.HibernateException; 8:TN,p
*6?h,Dt L
import org.flyware.util.page.Page; Wyd,7]'z)Z
import org.flyware.util.page.PageUtil; ]^$3S
Q!iM7C!8
import com.adt.bo.Result; l`4hWs\I
import com.adt.dao.UserDAO; n3-5`Jti
import com.adt.exception.ObjectNotFoundException; [}} ?a
import com.adt.service.UserManager; mbK$_HvU
FIDV5Y/f
/** &;DK^ta*P
* @author Joa HM/2/
/
*/ R<I)}<g(A3
publicclass UserManagerImpl implements UserManager { ozy~`$;c
]nY,%XE
private UserDAO userDAO; UOC>H%r~M?
5ro^<P0f**
/** w9Bbvr6
* @param userDAO The userDAO to set. qwM71B!r
*/ 6 GqR]KD
publicvoid setUserDAO(UserDAO userDAO){ @(<C {
this.userDAO = userDAO; Zn0e#n
} XEl-5-M"
?S9? ?y/
/* (non-Javadoc) MH7 n@.t
* @see com.adt.service.UserManager#listUser P|%uB'|H
Dukvi;\
(org.flyware.util.page.Page) 8w/$!9[
*/ K%iWUl;
public Result listUser(Page page)throws 4c^WQ>[
pY]T32
HibernateException, ObjectNotFoundException { v"ZNS
int totalRecords = userDAO.getUserCount(); ^,O%E;g^#
if(totalRecords == 0) rO4R6A
throw new ObjectNotFoundException AtU%S9
[}:;B$,
("userNotExist"); HueGARS
page = PageUtil.createPage(page, totalRecords); a8nqzuI
List users = userDAO.getUserByPage(page); GWd71ZtFO
returnnew Result(page, users); 2[}
O:
} +)$oy]
b$FK}D5
} ISa}Km>Q
Sq22]
O?,Grn%'.
<OgwA$abl%
D]tI's1
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 kA/4W^]Ws
}Um,wY[tK
询,接下来编写UserDAO的代码: 0MpZdJ
3. UserDAO 和 UserDAOImpl: *{y({J
java代码: =1#obB
,L_u
X
<8)cr0~zy>
/*Created on 2005-7-15*/ 0nr 5(4h
package com.adt.dao; ICdfak
A4{14Y;?
import java.util.List; d)>b/0CZ
-XASS%
import org.flyware.util.page.Page; i8w/a
?kM2/a"{G
import net.sf.hibernate.HibernateException; CH9Psr78
m+|yk.md
/** PPAcEXsIu
* @author Joa y:',)f }
*/ G22{',#r8
publicinterface UserDAO extends BaseDAO { "f~*4g
0ZM#..3sI
publicList getUserByName(String name)throws 'nIKkQ" N
"LNLM
HibernateException; I3qTSX-
0?o<cC1Z
publicint getUserCount()throws HibernateException; rSa=NpFxLu
3p1U,B}
publicList getUserByPage(Page page)throws V1#:[o63+
p!o-+@ava
HibernateException; Np"~1z.(b
Y(RB@+67
} ,Dab(
tdsfCvF=a
8,@0~2fz#
M ]Hf>7p
^ItL_4
java代码: x,NV{uG$n
%(1Jt"9|
}U'VVPh_
/*Created on 2005-7-15*/
:al
,zxs
package com.adt.dao.impl; u!-v1O^[
dsU'UG7L
import java.util.List;
od)ssL&E~
+ )n}n5
import org.flyware.util.page.Page; qizQt]l
GdYQq.
import net.sf.hibernate.HibernateException; .?`8B9w
import net.sf.hibernate.Query; p\P)
/_X`i[
import com.adt.dao.UserDAO; U7''; w
9m.MGJbQ_f
/** >,ABE2t5
* @author Joa |>RNIJ]
*/ LGK&&srJs
public class UserDAOImpl extends BaseDAOHibernateImpl xO^lE@a o
T/FZn{I
implements UserDAO { j}O qWX>/
|xF!3GGms
/* (non-Javadoc) ejia4(Cd
* @see com.adt.dao.UserDAO#getUserByName |- <72$j
p, T4BO
(java.lang.String) b<%c ]z
*/ -'F27])
publicList getUserByName(String name)throws Qz89=#W
DheQcM
HibernateException { &e78xtA{
String querySentence = "FROM user in class D |=L)\
&2Ef:RZF
com.adt.po.User WHERE user.name=:name"; $;&l{=e2)
Query query = getSession().createQuery S['cX ~
CH#K0hi
(querySentence); xs&xcRR"
query.setParameter("name", name); mo+!79&
return query.list(); .Cf!5[0E
} l-P6B9e|\
?6]B6
/* (non-Javadoc) +f%"O?
* @see com.adt.dao.UserDAO#getUserCount() `kE7PXqa
*/ N~0ihTG5
publicint getUserCount()throws HibernateException { 1]9w9!j
int count = 0; (S4HU_,88
String querySentence = "SELECT count(*) FROM vvG"rU
]28j$)6
user in class com.adt.po.User"; `!spi=f
Query query = getSession().createQuery r{B28'f[
=j{tFxJ
(querySentence); *?*~<R
count = ((Integer)query.iterate().next Mna
yiJl
xjSzQ|k-
()).intValue(); &4+|{Zx0
return count; LuHRB}W
} PU[<sr#,
alB'l
/* (non-Javadoc) }#-@5["-X
* @see com.adt.dao.UserDAO#getUserByPage xticC>
}O>4XFj
(org.flyware.util.page.Page) W9pY=9]p+
*/ ya{`gjIlW
publicList getUserByPage(Page page)throws #0vda'q=j
`U b*rOMu
HibernateException { 8sU5MQ5
String querySentence = "FROM user in class kz1#"8Zd!
QeC\(4?
com.adt.po.User"; Ov<c1y;f
Query query = getSession().createQuery nGe4IY\-w
4H(8BNgzV
(querySentence); G<=I\T'g;
query.setFirstResult(page.getBeginIndex()) :V5 Co!/+
.setMaxResults(page.getEveryPage()); $,J}w%A
return query.list(); 0O,;[l
} 4sntSlz)~k
J4"A6`O
} RRPPojKZ
jL8A_'3B
{hJCn*m_
<8;~4"'a
[5p 3:D
至此,一个完整的分页程序完成。前台的只需要调用 $ZGup"z)
W^h,O+vk
userManager.listUser(page)即可得到一个Page对象和结果集对象 fkp(M
05k'TqT{c
的综合体,而传入的参数page对象则可以由前台传入,如果用 Wh..QVv
wM4{\ f\
webwork,甚至可以直接在配置文件中指定。 }~|`h1JF
Q-V8=.
下面给出一个webwork调用示例: ]W$G!(3A
java代码: g_IcF><F
S9P({iZK
:e=7=|@7
/*Created on 2005-6-17*/ 0RtZTCGO
package com.adt.action.user; zN!yOlp5
y>x"/jzF#
import java.util.List; <uv`)Q 9
%6 Av1cv
import org.apache.commons.logging.Log; C5-u86F
import org.apache.commons.logging.LogFactory; \t1#5
import org.flyware.util.page.Page; x%r$/=
eu" m0Q
import com.adt.bo.Result; $)"T9$>$
import com.adt.service.UserService; &hkD"GGe
import com.opensymphony.xwork.Action; NZv 8#
[KYq01cj
/** M&V4|D
* @author Joa C_/eNu\I
*/ o.NU"$\?
publicclass ListUser implementsAction{ Z(tJd,
-e(<Jd_=
privatestaticfinal Log logger = LogFactory.getLog QxLrpM"O
=23B9WT
(ListUser.class); Uz,P^\8^$
Ncbe{}<md
private UserService userService; 5I6?gv/
,"`3N2!Y}
private Page page; #&IrCq+
%A~. NNbS
privateList users; xj U0&
PSu]I?WF
/* nbP}a?XC
* (non-Javadoc) c^1JSGv
* y'8T=PqY[t
* @see com.opensymphony.xwork.Action#execute() @q<h.#9
*/ =/|GWQj
publicString execute()throwsException{ u c!6?+0h
Result result = userService.listUser(page); KYB3n85 1
page = result.getPage(); ,Aq, f$5V
users = result.getContent(); B^dMYFelJ
return SUCCESS; p%>!1_'(
} W%ix|R^2]
Ja*,ht(5
/** l2Py2ZI-b
* @return Returns the page. ~oSA&v4V
*/ :%mlsNw
public Page getPage(){ wjX0r7^@
return page; nY1PRX\
} #Qz9{1\G
5?>Q[a.Ne
/** 502(CO>
* @return Returns the users. w].DLoz
*/ 78xiT
publicList getUsers(){ 5C`Vno~v
return users; u_ :gqvC=
} Ve[Kv07
e
jk?If 07
/** f~=e
* @param page t9W* N\
* The page to set. O[1Q#
*/ mrE>o!
publicvoid setPage(Page page){ PB8U+
this.page = page; :WH0=Bieh
} cru&nH*O^
}F V_jJ
/** = "Lb5!
* @param users :8)3t! A
* The users to set. 0_>1CW+X
*/ 9J49s1
publicvoid setUsers(List users){ )buy2#8UW
this.users = users; W-RshZ\
} :oZ~&H5Q
QE;,mC>
/** zBrqh9%8e
* @param userService ]tK<[8Y
* The userService to set. k
lr1"q7
*/ M|z4Dy
publicvoid setUserService(UserService userService){ +>mU4Fwp
this.userService = userService; It'PWqZtG
} |oOA;JC)(
} ?y* yl
J72kjj&C
U3>ES"N
''EFh&F
|2X+( F Ed
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, $>l65)(E\
~m7?:(/lb
可以通过配置文件来进行配置,例如,我想每页显示10条记录,那 h7\16j
zv\T ;_
么只需要: ^zS|O]Tx
java代码: wAF#N1-k
h4M>k{
r<kqs,-~
<?xml version="1.0"?> 7bam`)n
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork 9[\$\l
"g;}B"rG
1.0//EN" "http://www.opensymphony.com/xwork/xwork- iJ`v3PP
W(*?rA- PP
1.0.dtd"> f'M7x6W
M*jn8OE
<xwork> V0$:t^^
N^tH&\G\m
<package name="user" extends="webwork- UazUr=|e
u#34mg..
interceptors"> e#uF?v]O
yYZ0o.<&T*
<!-- The default interceptor stack name .[:*bo3
e~BUAz
--> <Okl.Iz>
<default-interceptor-ref !Ry4w|w
SE!0f&
name="myDefaultWebStack"/> `zRm
"G
L[:b\O/p,
<action name="listUser" pSJc.j
!"x&tF
class="com.adt.action.user.ListUser"> -r"h[UV)
<param 1{X ;&y
nqyB,vv0
name="page.everyPage">10</param> FY;R0+N
<result APu cA
Bl)DuCV
name="success">/user/user_list.jsp</result> h/n&&J
</action> okZDxg`6
CR<Nau>
</package> RBzBR)@5
o}K!p%5_
</xwork> 7$* O+bkn:
v81H!c.*
/"<o""<]
!,< )y}L^)
;4 ON
Ui`Z>,0sFi
这样就可以通过配置文件和OGNL的共同作用来对page对象设置初值 x7]Yn'^'
@eGJ_ J
了。并可以通过随意修改配置文件来修改每页需要显示的记录数。 g4 |s9RMD
.-g++f(_i
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 ^/kn#1H7&
gf8DhiB
#A2)]XvY
oopACE>
Yw\PmRL"p
我写的一个用于分页的类,用了泛型了,hoho amn\#_(
CcHf1
_CI
java代码: KGsH3{r
jLs-v
_JjR=
m
package com.intokr.util; v}$KlT
[l2ds:
import java.util.List; D|}%(N@sl
Rx22W:S=C.
/**
S=o1k
* 用于分页的类<br> *L3>:],7
* 可以用于传递查询的结果也可以用于传送查询的参数<br> 2R!1Vl
* *c+Kqz-
* @version 0.01 /{';\?w
* @author cheng A@X&dy
*/ %!G]H
public class Paginator<E> { I'h6!N"
privateint count = 0; // 总记录数 Fx.hti
privateint p = 1; // 页编号 JEK6Ms;)A
privateint num = 20; // 每页的记录数 9oK#n'hjb
privateList<E> results = null; // 结果 dcgz<m
SJRiMR_F~
/** k#I4^
* 结果总数 tf?u ;n
*/ 4{h?!Z*
publicint getCount(){ QGYO{S
return count; &!uNN|W
} n y7G
xbFoXYqgP
publicvoid setCount(int count){ ,iXE3TN;W
this.count = count; `[<j5(T
} p#9.lFSX
ik@g; >pQD
/** MZGN,[~)6
* 本结果所在的页码,从1开始 }vRs n-E@
* _y q"F#,*
* @return Returns the pageNo. 30(O]@f~
*/ ;IC :]Zu
publicint getP(){ f -N:
return p; 4}FuoQL
} ?8g[0/
}xx[=t=nUf
/** wz-9+VN6
* if(p<=0) p=1 w`(EW>i
* ANNfL9:Jy
* @param p qm-G=EX
*/ !@9Vq6
publicvoid setP(int p){ bE-{
U/;
if(p <= 0) .z
u0GsU=
p = 1; [:x^ffs
this.p = p; 3%?01$k
} !7MC[z(|N
+$KUy>
/** Yyq:5V!
* 每页记录数量 :yN;_bC!b%
*/ @B;2z_Y!l
publicint getNum(){ e&G!5kz!
return num; g@!mV)c97
} ]de'v
_RT3Fk
/** hr&&"d {s
* if(num<1) num=1 ^EGe%Fq*x]
*/ D[2I_3[wp
publicvoid setNum(int num){ [hs_HYqJ
if(num < 1) d'~
k f#
num = 1; H]V@Q~?e
this.num = num;
h:iK;
} ?\MvAG7Y
MA\"JAP/
/** T/DKT1P-
* 获得总页数 8<UD#i@:C
*/ ?;pw*s1Atz
publicint getPageNum(){ V)M+dhl
return(count - 1) / num + 1; E5D5
} 413,O~^
OOy]:t4 /
/** |~b.rKQt[
* 获得本页的开始编号,为 (p-1)*num+1 m6J7)Wp
*/ q:4 51 C
publicint getStart(){ >U\,(VB
return(p - 1) * num + 1; }eUeADbC
} }gQ FWT
X~ n=U4s}O
/** +}H2|vP
* @return Returns the results. QeP8Vl&e:
*/ J;|r00M
publicList<E> getResults(){ s&