Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 +u_mT$|T
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 +XWXHt
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据这一功能,我设计了通用的抽象Bean基类和分页类支持,代码来 UeE& 8{=d
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自于Quake Wang的javaeye-core包的相应类,然后又做了很多修改 )+w0NhJw
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分页支持类: txr!3-Ne'!
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java代码: m{Q{ qJ5>
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package com.javaeye.common.util; )X\3bPDJR
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import java.util.List; \ox:/-[c\<
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publicclass PaginationSupport { 0; V{yh
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publicfinalstaticint PAGESIZE = 30; vR1%&(f{
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privateint pageSize = PAGESIZE; 7-e)V{A`w
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privateList items; ~>}BDsM
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privateint totalCount; =NJb9S&8A
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privateint[] indexes = newint[0]; Y/Y746I
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privateint startIndex = 0; WlZ[9,:p1
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public PaginationSupport(List items, int vn}Vb+@R
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totalCount){ Y]8l]l 1
setPageSize(PAGESIZE); BzWmV.5
setTotalCount(totalCount); |k
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setItems(items); Mm.!$uR
setStartIndex(0); ,PN>,hFL
} FLy|+4D_%4
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public PaginationSupport(List items, int `m'2RNSc+#
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totalCount, int startIndex){ :^iR&`2~
setPageSize(PAGESIZE); B)^]V<l(w
setTotalCount(totalCount); ,rX!V=Z5
setItems(items); G2L7_?/m
setStartIndex(startIndex); J)g(Nw,O
} Za}91z"
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public PaginationSupport(List items, int yDd&*;9%Qg
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totalCount, int pageSize, int startIndex){ /h2`?~k+
setPageSize(pageSize); C5sV-UMR
setTotalCount(totalCount); 'inWV* P*g
setItems(items); 9pjk3a
setStartIndex(startIndex); n }MG
} VCc4nn#
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publicList getItems(){ o~GhV4vq
return items; F1Z20)8K
} 54}s:[O
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publicvoid setItems(List items){ =ARI*
this.items = items; * rs_k/2(
} _r,# l5~U
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publicint getPageSize(){ T@Q.m.iV4
return pageSize; <,cD EN7
} t<: XY
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publicvoid setPageSize(int pageSize){ )O7 Mfr
this.pageSize = pageSize; +JQN=nTA
} d0N7aacY
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publicint getTotalCount(){ eN jC.w9
return totalCount; pCg0xbc`
} 1^$Io}o:S
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publicvoid setTotalCount(int totalCount){ ~KX!i
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if(totalCount > 0){ +F0M?,
this.totalCount = totalCount; s}HTxY;
int count = totalCount / i.byHz?/
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pageSize; O~xc>
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if(totalCount % pageSize > 0) 4s$))x9p
count++; Y8CXinh
indexes = newint[count]; g\jdR_/
for(int i = 0; i < count; i++){ %OzxR9
indexes = pageSize * 'vCFT(C-
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i; h"<rW7z
} 2KPXRK
}else{ -EL"Sv?
this.totalCount = 0; f:HRrKf9
} q=6M3OnS>
} \GPWC}V\s
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publicint[] getIndexes(){ 2j_L
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return indexes; U:IQWl C
} >+G=|2
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publicvoid setIndexes(int[] indexes){ p- Q1abl
this.indexes = indexes; oFY'Ek;d
} #%E~IA%
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publicint getStartIndex(){ 8# 9.a]AX
return startIndex; o{ U=
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} %3~jg
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publicvoid setStartIndex(int startIndex){ rVZkG,Q
if(totalCount <= 0) X\flx~
this.startIndex = 0; .Z9Bbab:
elseif(startIndex >= totalCount) xe_c`%_
this.startIndex = indexes M(5l Su
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[indexes.length - 1]; 1k;X*r#
elseif(startIndex < 0) Plt~l3_
this.startIndex = 0;
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else{ 6LUB3;g7
this.startIndex = indexes H!7/U_AH
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[startIndex / pageSize]; XFH7jHnL+U
} QCMt4`%'u
} bY]aADv\
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publicint getNextIndex(){ +jQW 6k#
int nextIndex = getStartIndex() + -k!UcMWP
Pq !\6s@
pageSize; i]YH"t8GY
if(nextIndex >= totalCount) Dy0RZF4_
return getStartIndex(); VYik#n>|Gp
else 8BBuYY{
return nextIndex; td{$c6
} 8*6U4R
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publicint getPreviousIndex(){ i.6c;KU
int previousIndex = getStartIndex() - KN_3]-+B
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pageSize; ?3"lI,!0
if(previousIndex < 0) 5_0Eh!sx
return0; REc69Y.k
else S0du,A~
return previousIndex; -I'#G D>
} 8)/d8@
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} <U$x')W
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抽象业务类 k_/*>lIZY
java代码: ?
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/** b<n*wH
* Created on 2005-7-12 eD4X:^@
*/ #Ipi 3
package com.javaeye.common.business; n#|ljC
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import java.io.Serializable; =+DfIO
import java.util.List; ]{s0/(EA
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import org.hibernate.Criteria; s'b 4Me
import org.hibernate.HibernateException; Je5}Z.3m
import org.hibernate.Session; ?(0=+o(`
import org.hibernate.criterion.DetachedCriteria; O`K2mt\%
import org.hibernate.criterion.Projections; c#(Hh{0
import JuQwZ]3ed
m Q4(<,F
org.springframework.orm.hibernate3.HibernateCallback; VddHK
import
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org.springframework.orm.hibernate3.support.HibernateDaoS :y'EIf
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upport; @<(4J
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import com.javaeye.common.util.PaginationSupport; E@,m+
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public abstract class AbstractManager extends z36wWdRa6
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HibernateDaoSupport { ckGmwYP9
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privateboolean cacheQueries = false; }D># AFs6#
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privateString queryCacheRegion; P9`R~HO'`
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publicvoid setCacheQueries(boolean @<NuuYQ&
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cacheQueries){ t:MSV?
this.cacheQueries = cacheQueries; Z<^;Ybw{`Z
} m<H{@ZgN(
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publicvoid setQueryCacheRegion(String IjGPiC
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queryCacheRegion){ Nv=78O1
this.queryCacheRegion = 2ah%,o
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queryCacheRegion; !O,Sq/=.
} {{jV!8wK
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publicvoid save(finalObject entity){ y];-D>jk
getHibernateTemplate().save(entity); ~)^'5^
} !_vxbfZO
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publicvoid persist(finalObject entity){ \?pyax8
getHibernateTemplate().save(entity); ,jOJ\WXP
} I)tiXcJw
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publicvoid update(finalObject entity){ ia7<AwV
getHibernateTemplate().update(entity); ')U~a
} H1I^Vij
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publicvoid delete(finalObject entity){ sxsb)a
getHibernateTemplate().delete(entity); J91[w?,
} xNzGp5H
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publicObject load(finalClass entity, CJ*
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} vmRm*8z
finalSerializable id){ )\|+G5#`
return getHibernateTemplate().load MfP)Pk5
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(entity, id); )P$|9<_q7x
} < cvh1~>(
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publicObject get(finalClass entity, &^r>Q`u
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finalSerializable id){ 51SmoFbMz
return getHibernateTemplate().get <.Ws; HN}
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(entity, id); `
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} 1@DC#2hPr
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publicList findAll(finalClass entity){ JVYH b 60Z
return getHibernateTemplate().find("from y3zP`^
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" + entity.getName()); );$99t
} j,.\QwpU
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publicList findByNamedQuery(finalString E5w;75,
)th[fUC(
namedQuery){ O`B,mgT(
return getHibernateTemplate `gX@b^
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().findByNamedQuery(namedQuery); `#N/]4(j
} H$KO[mW}
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publicList findByNamedQuery(finalString query, xT%`"eM}
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finalObject parameter){ mQj=-\p
return getHibernateTemplate Y{p$%
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().findByNamedQuery(query, parameter); XBQt:7[<
} !+eH8
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publicList findByNamedQuery(finalString query, *m~-8_ >;
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finalObject[] parameters){ [9 W@<p
return getHibernateTemplate c0qp-=^&.
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().findByNamedQuery(query, parameters); =p+y$
} ]~({;;3o-
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publicList find(finalString query){ /yOx=V
return getHibernateTemplate().find 1E+12{~m"i
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(query); l<6u@,%s
} c-a,__c?hx
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publicList find(finalString query, finalObject ,_2-Op
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parameter){ %;PpwI
return getHibernateTemplate().find ,T$ts
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(query, parameter); (|gQ
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} xa>| k>I
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public PaginationSupport findPageByCriteria _BczR:D*
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(final DetachedCriteria detachedCriteria){ 8-q^.<9
return findPageByCriteria aurs~
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); =BJe)!b
} W(, j2pU
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public PaginationSupport findPageByCriteria 8v4}h9*F"7
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(final DetachedCriteria detachedCriteria, finalint JJ?{V:
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startIndex){ ([>ecS@eO
return findPageByCriteria i5,iJe0cA
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(detachedCriteria, PaginationSupport.PAGESIZE, 18X@0e
+$2{u_m,
startIndex); \Wbmmd}8
} \br!77
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public PaginationSupport findPageByCriteria ;nY#/%f
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(final DetachedCriteria detachedCriteria, finalint s|[>@~gXk
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pageSize, x7j#@C
finalint startIndex){ (O.%Xbx3
return(PaginationSupport) 3DU1c?M:
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getHibernateTemplate().execute(new HibernateCallback(){ 04a
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publicObject doInHibernate dC11kqqj
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(Session session)throws HibernateException { u
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Criteria criteria = 'ofj1%c
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detachedCriteria.getExecutableCriteria(session); h$cm:uks
int totalCount = )uPJ?
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((Integer) criteria.setProjection(Projections.rowCount .3!Wr*o
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()).uniqueResult()).intValue(); s**<=M GK
criteria.setProjection >)><u4}
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(null); |Uh8b %
List items = .@1+}0
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criteria.setFirstResult(startIndex).setMaxResults ,75)
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(pageSize).list();
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PaginationSupport ps = (In{GA7;
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new PaginationSupport(items, totalCount, pageSize, 9&mSF0q
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startIndex); AGBV7Kk
return ps; @gUp9ZwtH
} yR}.Xq/
}, true); j"W>fC/u
} b)wcGBS
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public List findAllByCriteria(final n<?U6~F&~
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DetachedCriteria detachedCriteria){ ~!S3J2kG{
return(List) getHibernateTemplate NvK9L.K
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().execute(new HibernateCallback(){ |vI*S5kn6A
publicObject doInHibernate hmy%X`%j
@"w4R6l+*
(Session session)throws HibernateException { r(,U{bU<
Criteria criteria =
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detachedCriteria.getExecutableCriteria(session);
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return criteria.list(); rPxRGoR
} UQVL)-Z
}, true); 2.qPMqH
} XF`2*:7
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public int getCountByCriteria(final Mz+I
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DetachedCriteria detachedCriteria){ 4.A^5J'W
Integer count = (Integer) B|`?hw@g+
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getHibernateTemplate().execute(new HibernateCallback(){ 8$FH;=
publicObject doInHibernate s 6Wp"V(
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(Session session)throws HibernateException { ct+F\:e
Criteria criteria = 6)[moR{N1
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detachedCriteria.getExecutableCriteria(session); @2(u=E: ^
return `IHP_IfR
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criteria.setProjection(Projections.rowCount uHbg&eW
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()).uniqueResult(); DYX{v`>f^
} Bc>j5^)8w
}, true); O>`k@X@9/
return count.intValue(); oZ{,IZ45
} rFzNdiY
} *tjaac;z<J
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用户在web层构造查询条件detachedCriteria,和可选的 IIk_!VzT
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 (l5p_x
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PaginationSupport的实例ps。 |# 0'_
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ps.getItems()得到已分页好的结果集 a\sK{`|X*
ps.getIndexes()得到分页索引的数组 r3V1l8MV
ps.getTotalCount()得到总结果数 -TD\?Q
ps.getStartIndex()当前分页索引 T;M
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ps.getNextIndex()下一页索引 MqJTRBs%
ps.getPreviousIndex()上一页索引 $S>'0mL
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 MlTC?Rp#
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,尤其是上面的示例代码,让我着实觉得该对我原来的分页查询做 jCY~Wc
!mv5i%3
一下代码重构了。 tE%g)hL-
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我把原本我的做法也提供出来供大家讨论吧: Y:CX RU6eD
NV5qF/<M
首先,为了实现分页查询,我封装了一个Page类: A%#M#hD/
java代码: -!!]1\S*Y
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/*Created on 2005-4-14*/ SM~ ~:
package org.flyware.util.page; yjT>bu]
cs6oD!h
/** A=kOSq 4Q
* @author Joa #ss/mvc3
* ]9_gbQ
*/ fXWy9 #M
publicclass Page { Cl'$*h
yeyDB>#Va.
/** imply if the page has previous page */ 7V%P
privateboolean hasPrePage; #E+ybwA
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/** imply if the page has next page */ .I_atv
privateboolean hasNextPage; A~xw:[zy$a
kq X=3Zo
/** the number of every page */ KBM*7raA
privateint everyPage; g} !{_z
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/** the total page number */ TG;[,oa
privateint totalPage; _-BP?'lN
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/** the number of current page */ CHTK.%AQH!
privateint currentPage; u7mPp3ZYK
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/** the begin index of the records by the current (Y'cxwj%
xO_>%F^?
query */ 2d*bF.
privateint beginIndex; (zFqb,P
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/** The default constructor */ <O7!(
public Page(){ Vw H|ed$
@'>RGaPV
} Iuz_u2"C
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/** construct the page by everyPage p _[,P7
* @param everyPage ^'[QCwY~
* */ |K_%]1*riC
public Page(int everyPage){ \(Oc3+n6
this.everyPage = everyPage; ntLEk fK{
} e_e\Ie/pDc
N
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/** The whole constructor */ M?YNK]
public Page(boolean hasPrePage, boolean hasNextPage, PwW$=M{\.
]+Lr'HF
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int everyPage, int totalPage, ( mp
int currentPage, int beginIndex){ sJx_X8
this.hasPrePage = hasPrePage; hYpxkco"4'
this.hasNextPage = hasNextPage; nHm29{G0
this.everyPage = everyPage; C W#:'
this.totalPage = totalPage; .O"a: ^i
this.currentPage = currentPage; F oC
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this.beginIndex = beginIndex; C*ep8{B
}
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/** x)=l4A\
* @return 7YD+zd:
* Returns the beginIndex. FbroI>" e
*/ a%.W9=h=M(
publicint getBeginIndex(){ +Kb 7N, "
return beginIndex; <[\I`kzq
} UB5H8&Rf!
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/** 7(]F+\A3
* @param beginIndex w\s`8S
* The beginIndex to set. {,JO}Dmu5
*/ -9FGFBm4]
publicvoid setBeginIndex(int beginIndex){ *VhEl7
this.beginIndex = beginIndex; =S{OzF
} Hh Q0>
jbipNgxkr
/** :=y5713
* @return 1v|-+p42
* Returns the currentPage. "7y,d%H
*/ m|W17LhW{
publicint getCurrentPage(){ z*h:Nt%.
return currentPage; =tD*,2]
} aGC3&c[Wx
#dae^UjM
/** OJpfiZ@Q_
* @param currentPage 1l$C3c
* The currentPage to set. ]uox ^HC
*/ UgAp9$=z
publicvoid setCurrentPage(int currentPage){ GIzB1cl:
this.currentPage = currentPage; 0\:=KIY.
} D<69xT,
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/** U\Vg &"P
* @return x 4_MbUe
* Returns the everyPage. <b
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*/ :41Y
publicint getEveryPage(){ nSyLt6zn\
return everyPage; r\Y,*e
} r{v3XD/
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/** :rU.5(,
* @param everyPage }y6@YfV${
* The everyPage to set. rQ{|0+l
*/ iSO xQ
publicvoid setEveryPage(int everyPage){ ={%'tv`
this.everyPage = everyPage; /al56n
} buX(mj:&
AuQ|CXG-\
/** $B-/>Rz
* @return )).=MTk
* Returns the hasNextPage. V8 8u-
*/ `.J)Z=o
publicboolean getHasNextPage(){ v_5qE
return hasNextPage; yS~Y"#F!.
} y\^zxG*]'
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/** ]|g2V
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* @param hasNextPage "}Om0rB}1
* The hasNextPage to set. @>O7/d?O
*/ IW!x!~e
publicvoid setHasNextPage(boolean hasNextPage){ ^WB[uFt-
this.hasNextPage = hasNextPage; "qq$i35x
} h@R n)D
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/** $a~
* @return s?}qia\~m
* Returns the hasPrePage. DGGySO6=$e
*/ ,JdBVt
publicboolean getHasPrePage(){ 8(4!x$,Z5
return hasPrePage; ]2m=lt1
} J.XkdGQ
t RU/[?!
/** :epBd3f
* @param hasPrePage NOs00 H
* The hasPrePage to set. e">&B]#}
*/ v];YC6shx
publicvoid setHasPrePage(boolean hasPrePage){ @@\qso
this.hasPrePage = hasPrePage; mh"PA p
} 'Grej8
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/** Ewz cB\m
* @return Returns the totalPage. ub8d]GZJ
* @Dsw.@/
*/ \uHC 9}0
publicint getTotalPage(){ <!m.+
return totalPage; ^ulgZ2BQ|
} m&=Dy5
bMc[0
/** !q$VnqFk
* @param totalPage q(~jP0pj%
* The totalPage to set. O8#]7\)
*/ Caj H;K\
publicvoid setTotalPage(int totalPage){ b&yuy
this.totalPage = totalPage; SN"Y@y)=
} D6lzcf
p,z>:3M
} U0-RG
pSQX
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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 XS2/U<sd
8cZ[Kl%
个PageUtil,负责对Page对象进行构造: d1.@v;
java代码: z4D)Xy"/
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/*Created on 2005-4-14*/ K+/wJ9^B
package org.flyware.util.page; V(K;Gc
/NB|N*}O)
import org.apache.commons.logging.Log; |^Yz*r?BJ
import org.apache.commons.logging.LogFactory; U&(gNuR>J
x Y$x=)
/** 7>zUT0SS
* @author Joa m==DBh
* f8K0/z
*/ !_+FuF"@
publicclass PageUtil { 8[@Y`j8
_0
43,
privatestaticfinal Log logger = LogFactory.getLog lrkgsv6
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(PageUtil.class); p) ;[;S
}t(5n $go6
/**
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* Use the origin page to create a new page xv>8rW(Np5
* @param page oJ5n*[qUI
* @param totalRecords FDF DB
* @return {gEz;:!):
*/ ' p!&&.%
publicstatic Page createPage(Page page, int Q>X1 :Zn3
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totalRecords){ bly `mp8#
return createPage(page.getEveryPage(), fZap\
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page.getCurrentPage(), totalRecords); E rA*a3
} W4qT]m
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/** +Y+fM
* the basic page utils not including exception
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Ao\ OU}
handler kG4])qxC'
* @param everyPage G a$2o6
* @param currentPage { .i^&
* @param totalRecords LCIe1P2
* @return page {J)gS
*/ u1'l4VgT
publicstatic Page createPage(int everyPage, int I+Qt5Ox
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currentPage, int totalRecords){ R SWw4}
everyPage = getEveryPage(everyPage); @Z""|H"0
currentPage = getCurrentPage(currentPage); uu0t}3l
int beginIndex = getBeginIndex(everyPage, ?`
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^8ilUu
currentPage); %,8
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int totalPage = getTotalPage(everyPage, W^,p2
Q'e[(^8
totalRecords); './qBJ
boolean hasNextPage = hasNextPage(currentPage, nH?#_ 5F1
N#Nc{WU'B
totalPage); PM:u~D$Jd
boolean hasPrePage = hasPrePage(currentPage); p)Ht =~
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returnnew Page(hasPrePage, hasNextPage, N4yQ,tG>aa
everyPage, totalPage, ]xV2=!J
currentPage, R6o07.]
7S_"h*Ud
beginIndex); V22Br#+
} q+4<"b+6G
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privatestaticint getEveryPage(int everyPage){ CfOhk
return everyPage == 0 ? 10 : everyPage; ,I f9w$(z
} bHs},i6
l2!ztK1^
privatestaticint getCurrentPage(int currentPage){ D0gz
((
return currentPage == 0 ? 1 : currentPage; kI*f}3)Y
} UPuG&A#VV
I'R|B\
privatestaticint getBeginIndex(int everyPage, int b]Lp_t
y8di-d3_
currentPage){ ,f~8:LHq
return(currentPage - 1) * everyPage; 8;,(D#p
} /-ewCCzZV
<5c^DA
privatestaticint getTotalPage(int everyPage, int <oTNo>U/k
VpM(}QHd
totalRecords){ v`"BXSmp{
int totalPage = 0; !xC IvKW
C #@5:$
if(totalRecords % everyPage == 0) d6e]aO=g
totalPage = totalRecords / everyPage; hQJ-
~
else m&6I@S2
totalPage = totalRecords / everyPage + 1 ; w}(Ht_6q{
(=D^BXtH|
return totalPage; R8u9tTW
} /5R?(-
.t%`"C
privatestaticboolean hasPrePage(int currentPage){ 0yKPYA*j
return currentPage == 1 ? false : true; rgrsNr:1
} 4d
@
(>
G c:oSvm
privatestaticboolean hasNextPage(int currentPage, R%%h=]
0p \,}t\E
int totalPage){ @1peJJ{
return currentPage == totalPage || totalPage == 'miY"L:| O
zJtB?<
0 ? false : true; JiHk`e`
} G2_l}q~
3l''
8` f=Eh
} h*zHmkFR
Vbpt?1:
`n`aA)|<
<-a6'g2y
"0A !fRI~
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。 rXg#_c5j
gJI(d6
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 "( P-VX
g:>Mooxzi
做法如下: Nm=\~LP90
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 6`hHx=L
g6 T /k7a
的信息,和一个结果集List: J |TA12s
java代码: ;b1*2-
Snf1vH
-_|U"C$
/*Created on 2005-6-13*/ =^A/&[&31
package com.adt.bo; k'$UA$2d
LTc=D
import java.util.List; ^ s@'nKc
J$Nc9?|ZZ
import org.flyware.util.page.Page; LZG~1tf
`(7HFq<N
/** 6H_7M(f
* @author Joa 5PU$D`7it
*/ $s-HG[lX[
publicclass Result { MX{p)(HW
9&uWj'%ia
private Page page; XQ]5W(EP
LlfD>cN
private List content; Ohmi(s
(qM(~4|`
/** 'v*Y7zZ#K
* The default constructor Pq:GvM`
*/ - &/n[EE
public Result(){ ?YO$NYwE
super(); )cX6o[oia
} Nn;p1n
dN
!(EJ. |LH
/** gqf*;Z eU
* The constructor using fields ,TAzJ
* Tv{X$`%
* @param page ]M;aVw<!
* @param content !@x'?+
*/ 9"YOj_z
public Result(Page page, List content){ HFL(t]
this.page = page; .v3~2r*&
this.content = content; )Ekp <2B:0
} MQv2C@K9F
HjO-6F#s
/** 62X;gb
* @return Returns the content. noBGP/Av=:
*/ hKtc
publicList getContent(){ clZjb
return content; pv2u.qg5z
} +h$)l/>:
/k(KA [bS
/** x]gf3Tc58
* @return Returns the page. ]~SOGAFW
*/ =2z9Aq{
public Page getPage(){ QJaF6>m
return page; fr1/9E;
} "@JSF
'Zdjd]
/** F~cvob{
* @param content Rmrv@.dr!
* The content to set. Z[DiLXHL
*/ 0"~`U.k~M
public void setContent(List content){ ,h'q}5
this.content = content; [4qx+ypT
} (YbRYu
Q-X<zn
/** 'Lw4jq
* @param page j7vp@l6`L
* The page to set. Kzw)Q
*/ )vFJx[a<n`
publicvoid setPage(Page page){ abq$OI
this.page = page; ?t&sT
} H}OOkzwrA
} LeA=*+zP[
idLysxN
f((pRP
K; 7o+Xr
Xj/U~
2. 编写业务逻辑接口,并实现它(UserManager, 5YlY=J
[/}y!;3iXM
UserManagerImpl) Md9b_&'
java代码: l^s\^b=W
Zc"Vf]:
&R54?u^A
/*Created on 2005-7-15*/ :>U2yI
package com.adt.service; N`tBDl"ld
fX,L;Se"
import net.sf.hibernate.HibernateException; =#@eDm%
`.f
{V
import org.flyware.util.page.Page; gWo `i
AnV\{A^
import com.adt.bo.Result; qW57h8M
o0Z(BTO
/** <MhjvHg
* @author Joa LFsrqdzJ
*/ h&3*O[`
publicinterface UserManager { oyGO!j
" h,<PF
public Result listUser(Page page)throws &u62@ug#}
pKf]&?FX
HibernateException; oT7=
;}!hgyq
} @J~n$^ke
), >jBYMJ
L lmdydC%
;-=Q6Ms8
~{,U%B
java代码: ;P9P2&c8c
`I(#.*
&Q>)3] |p
/*Created on 2005-7-15*/ >uS?Nz5/
package com.adt.service.impl; bI)ItC_wf!
nezdk=8J/
import java.util.List; fk%yi[
?@U7tNI
import net.sf.hibernate.HibernateException; MHN?ZHC)
TqbDj|7`R
import org.flyware.util.page.Page; KX e/i~AS
import org.flyware.util.page.PageUtil; .\kcWeC\
8}m bfuo1
import com.adt.bo.Result; 49%qBO$R
import com.adt.dao.UserDAO; J:
import com.adt.exception.ObjectNotFoundException; +.N3kH
import com.adt.service.UserManager; z4f\0uQ
>[ r
TUn;
/** ZCJOh8
* @author Joa s;'XX}Y
*/ uJz<:/rwZ-
publicclass UserManagerImpl implements UserManager { 8(R%?>8
7 jq?zS|
private UserDAO userDAO; UGuEZ-r
"mbcZ5_
/** 7^|oO~x6
* @param userDAO The userDAO to set. Vv=/{31
*/ e0O2>w
publicvoid setUserDAO(UserDAO userDAO){ b #U
nE
this.userDAO = userDAO; o]0v#2l'
} E#t;G:+A
ncg5%(2
/* (non-Javadoc) P-9[,3Zd
* @see com.adt.service.UserManager#listUser Nx~9Ug
-TKS`,#
(org.flyware.util.page.Page) ZhqrN]x
*/
%{\|/#>:
public Result listUser(Page page)throws 5'f4=J$Z)
+g_+JLQ
HibernateException, ObjectNotFoundException { H=E`4E#k
int totalRecords = userDAO.getUserCount(); ;SAurG$
if(totalRecords == 0) W:q79u yX
throw new ObjectNotFoundException Fy|tKMhnc
ta]B9&c
("userNotExist"); 6e,|HV
page = PageUtil.createPage(page, totalRecords); y,&UST
List users = userDAO.getUserByPage(page); J(*qOGBD
returnnew Result(page, users); NvH9?Ek"
} +]|aACt]
VuqN)CE^Uq
} h8;B +#f`
V{17iRflf
`YTagUq7
Bw-<xwD
Zw+VcZz3
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 .<zW(PW
K8NoY6
询,接下来编写UserDAO的代码: K;jV"R<9
3. UserDAO 和 UserDAOImpl: v3|-eWet^
java代码: SH>L3@Za
7%?2>t3~
Wz)O,X^
/*Created on 2005-7-15*/ w~J 7|8Y
package com.adt.dao; n>]`8+a~%X
mG4myQ?$
import java.util.List; ,"?h_NbF
Uc,D&Og
import org.flyware.util.page.Page; rU?sUm,ch
5/j7 C>
import net.sf.hibernate.HibernateException; ;,T3C:S?
b%`^KEvwfo
/** 9(?9yFbj5
* @author Joa eliT<sw8
*/ dQ6:c7hp>D
publicinterface UserDAO extends BaseDAO { FqQqjA
OiI[w8
publicList getUserByName(String name)throws ~hi \*W6jg
~(E.$y7P
HibernateException; yZup4#>8
nn>1OO
publicint getUserCount()throws HibernateException; \_?A8F
? b;_T,S[
publicList getUserByPage(Page page)throws $hexJzX
u6o:~=WwM
HibernateException; C[f'1O7
\]Nlka
} ^mWOQ*zi;
SMHQo/c r
3WdYDv]N}L
nY(>|!
, &>LBdG`
java代码: @<]sW*s
ML6Y_|6
|
l,cnMr^.W
/*Created on 2005-7-15*/ 6H+'ezM
package com.adt.dao.impl; 4 .7YIM
l1 (6*+
import java.util.List; X}T/6zk
EfxW^zm)
import org.flyware.util.page.Page; *|)a@VL
+ZH-'l
import net.sf.hibernate.HibernateException; ^)$(Fe<
import net.sf.hibernate.Query; ;Du+C%
p,_,o3@~
import com.adt.dao.UserDAO; WZz8VF
USF9sF0l
/** )8`7i{F
* @author Joa \G}02h
*/ K9{3,!1
public class UserDAOImpl extends BaseDAOHibernateImpl cd_\?7
"R8: s
implements UserDAO { ZAe'lgS
iuxI$
/* (non-Javadoc) =Uy;8et
* @see com.adt.dao.UserDAO#getUserByName |'mwr!
-Jqm0)2
(java.lang.String) Gn*cphb
*/ Y"Y%JJ.J
publicList getUserByName(String name)throws _+c' z
?D 8<}~Do
HibernateException { Ew`(x30E
String querySentence = "FROM user in class Q]44A+M]
R/!lDv!
com.adt.po.User WHERE user.name=:name"; 2o8:[3C5
Query query = getSession().createQuery ~_l@
_P5yz
PE!/ n6
(querySentence); z1dSZ0NoA
query.setParameter("name", name); 9jwcO)p^
return query.list(); G
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} }s+ t*z
KGM9
b
/* (non-Javadoc) |3LD"!rEx
* @see com.adt.dao.UserDAO#getUserCount() &,v-AL$:Q
*/ qq
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publicint getUserCount()throws HibernateException { }%8 :8_Ke
int count = 0; Lzr&Q(mL
String querySentence = "SELECT count(*) FROM `'W/uCpl
|uUGvIsXn
user in class com.adt.po.User"; *lZ;kW(}p
Query query = getSession().createQuery o7gYj\
W4OL{p-\/
(querySentence); T]er_n
count = ((Integer)query.iterate().next pyHU+B
-FOn%7r#Y
()).intValue(); mS$9D{
return count; bEQy5AX
} EF>vu+YK
lw\+!}8(
/* (non-Javadoc) _h6j, )
* @see com.adt.dao.UserDAO#getUserByPage !+UU[uM
8+f{ /
(org.flyware.util.page.Page) lpq)vKM}^
*/ N F$k~r
publicList getUserByPage(Page page)throws MZ2/ks
enC/@){~
HibernateException { C33BP}c]
String querySentence = "FROM user in class us5<18M5
/M :7
com.adt.po.User"; ;\]&k
Query query = getSession().createQuery `e`}dgf0S|
bIXudE[8zq
(querySentence); c;X%Ar
query.setFirstResult(page.getBeginIndex()) t)kc`3i<A
.setMaxResults(page.getEveryPage()); IdS=lN$
return query.list(); %K`th&331
} L[s`8u<_)z
7"_m?c8
} +TZVx(Z&A
aZ,j1j0p
*b}/fG)XZ
`<3%`4z/
QO/nUl0E
至此,一个完整的分页程序完成。前台的只需要调用 LULRi#n
I!?)}d
userManager.listUser(page)即可得到一个Page对象和结果集对象 G$^u2wz.
WaPuJ5;e
的综合体,而传入的参数page对象则可以由前台传入,如果用 f`s.|99Y
\wKnX]xGf
webwork,甚至可以直接在配置文件中指定。 XtZeT~/7RT
@+6cKP
下面给出一个webwork调用示例: 4C#r=Uw`
java代码: 34
'[O
LE|DMz|J
oO3X>y{gN
/*Created on 2005-6-17*/ Akdx1h,
package com.adt.action.user; s$JO3-)
`Hx JE"/
import java.util.List; dEI]|i
r
S"cim\9xP
import org.apache.commons.logging.Log; \>\_OfY1W
import org.apache.commons.logging.LogFactory; rQ-,mq
import org.flyware.util.page.Page; [ KDNKK
)GKY#O09x9
import com.adt.bo.Result; z41v5rB4
import com.adt.service.UserService; S^x?<kYQau
import com.opensymphony.xwork.Action; X%98k'h.y
35H.ZXQp-
/** ;d.gVR_V
* @author Joa g5;Ig
*/ m@y<wk(
publicclass ListUser implementsAction{ &X6hOc:``\
+,_%9v?3
privatestaticfinal Log logger = LogFactory.getLog 8
KRo<
V6bjVd9|Z
(ListUser.class); z?Cez*.h>
c
'rn8Jo}
private UserService userService; p=[SDk`
)!lx'>0>
private Page page; 2@!B;6*8q
k#n%at.g
privateList users; YCq:]
gh-i|i,
/* -Rwx`=6tV
* (non-Javadoc) $q##Tys
* L%<DLe^P`l
* @see com.opensymphony.xwork.Action#execute() tZY6{,K%4
*/ d5"rCd[
publicString execute()throwsException{
(F&o!W
Result result = userService.listUser(page); "vfpG7CG
page = result.getPage(); H@te!EE
users = result.getContent(); '?$R YU,
return SUCCESS; y" |gC!V}
} 6lL^/$]
9/=+2SZ
/** VsDY,=Ww
* @return Returns the page. G0h e'BR
*/ aP]h03sS
public Page getPage(){ zJ_y"bt
return page; r%9=75HA
} LvMA('4
? ph>:M
/** 6 $K@s
* @return Returns the users. vwzElZ{C:v
*/ ?aguAqG$
publicList getUsers(){ V}ls|B$Y
return users; =imJ0V~RW
} L9]d$ r"
y@r0"cvz9
/** xX@9wNYD
* @param page fVJWW):
* The page to set. dsg-;*%
*/ )SJ"IY\P
publicvoid setPage(Page page){ a+j"8tHu$
this.page = page; dU2:H}
} #8$"84&N.
SX&Q5:
/** K'y|_XsBB)
* @param users yG;@S8zC
* The users to set. e@1A_q@.
*/ j9X|c7|
publicvoid setUsers(List users){ ,20l` :
this.users = users; j.[W] EfL~
} #|T2`uYotf
T:" .{h-i
/** cdN =HM~I
* @param userService ,YJn=9pTl
* The userService to set. <`?%Cz AO
*/ j<k-w
publicvoid setUserService(UserService userService){ #N;&^El
this.userService = userService; FV{XPr%
} &Mz]y?k'
} q7I!wD9Cff
s~ou$!|
]<K"`q2
5vLA)Al3
7*
[
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, RRQIlI<
t*)!BZ
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 8c>xgFWp9
2%*\XPt)
么只需要: 7-0j8$`
java代码: =\mJ5v"hA
P#V}l'j(<a
QMy1!:Z&!
<?xml version="1.0"?> >nvnU`\
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork O<ybiPR
:^-\KE`3
1.0//EN" "http://www.opensymphony.com/xwork/xwork- aMVq%{U
0{I-x^FI
1.0.dtd"> )1YX+',"
X4+H8],)
<xwork> LXZI|K[}k
!R@jbM
<package name="user" extends="webwork- Z{/GT7 /
Yh Ow0 x
interceptors"> i52JY&N
G(ZEP.h`u
<!-- The default interceptor stack name i|xz
=pTTXo
--> 1f'msy/
<default-interceptor-ref ,6o tm
i g
.
name="myDefaultWebStack"/> \cf'Hj}
-s1.v$g
<action name="listUser" nrX+ '
LOr( HgyC
class="com.adt.action.user.ListUser"> cmAdQ)(Kzd
<param %;|dEY
6{0MprY
name="page.everyPage">10</param> TuaP
<result j)#yyK{k2s
N1.fV -
name="success">/user/user_list.jsp</result> EWY'E;0@5
</action> 7 toIbC#
Xbrc_V\_
</package> 9MQjSNYzo
9XhH*tBn7(
</xwork> WF_QhKW|k
]EUQMyR
>>"@0tO
7\ZSXQy1W
cYXL3)p*Q
0c8_&
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 * dk(<g=fM
K-K>'T9F}
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。 t;-F]
*B84Y.d f
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 )4.-6F7U?
z-:>[Sn
MJCz %zK
z@V9%xF-3
k@h0 }%
我写的一个用于分页的类,用了泛型了,hoho #&fu"W+D96
JG7K-W|!c
java代码: -M_>]ubG
}B!io-}
#0\* 86
package com.intokr.util; ^dsj1#3z
o^MoU2c
import java.util.List; `e?~c'a@
wXKt)3dm u
/** lV$#>2Hh5
* 用于分页的类<br> Mn<s9ITS-
* 可以用于传递查询的结果也可以用于传送查询的参数<br> ^]~!:Ej0
* @*- 6DG-f
* @version 0.01 ):}A Quy]
* @author cheng N8x.D-=gG
*/ TIR Is1
public class Paginator<E> { !IB}&m
privateint count = 0; // 总记录数 %+<1X?;,Fq
privateint p = 1; // 页编号 rk@qcQR
privateint num = 20; // 每页的记录数 xU6dRjYhH9
privateList<E> results = null; // 结果 8.7q
-<Q
^U96p0H"T
/** *[BtW56-
* 结果总数 &A`,hF8
*/ R,=8)OI2
publicint getCount(){ (0.JoeA`y
return count; 7zJ2n/`m*
} Q<ia
Uj3HAu
publicvoid setCount(int count){ j]]5&u/l
this.count = count; Q&_#R(3j;
} IiE^HgM
JnIG;/
/** J&