Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 x?6^EB|@
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 :n<l0
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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 p^{yA"MQ
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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 Yo5ged]i
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。 ?~^p:T
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分页支持类: WFug-#;e
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java代码: pdQaVe7tRo
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package com.javaeye.common.util; M;-FW5O't
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import java.util.List; 5*"WS $
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publicclass PaginationSupport { BhyLcUBuB
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publicfinalstaticint PAGESIZE = 30; iee`Yg!EOH
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privateint pageSize = PAGESIZE; jN+2+P%OL
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privateList items; 78mJ3/?rC
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privateint totalCount; '#r^W2
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privateint[] indexes = newint[0]; k"`^vV[{F
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privateint startIndex = 0; toox`|
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public PaginationSupport(List items, int U%2{PbL
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totalCount){ n{F&GE="
setPageSize(PAGESIZE); .O4=[wE!U
setTotalCount(totalCount); na/,1iI<
setItems(items); du=[ r
setStartIndex(0); wB*}XJah
} 0vz!)
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public PaginationSupport(List items, int kL}*,8s{
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totalCount, int startIndex){ h3-dJgb
setPageSize(PAGESIZE); dC}4Er
setTotalCount(totalCount); LTio^uH
setItems(items); EO.}{1m=hx
setStartIndex(startIndex); =$%_asQJ
} D|5Fo'O^AV
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public PaginationSupport(List items, int E'_$?wWn5
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totalCount, int pageSize, int startIndex){ hrnY0
setPageSize(pageSize); Bdf]?s[]
setTotalCount(totalCount); 1A9Gf
setItems(items); Ds%~J
setStartIndex(startIndex); ,Z]4`9c
}
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publicList getItems(){ RjQdlr6*
return items; qgLj^{
} [U?a %$G>
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publicvoid setItems(List items){ ,n+~S^r
this.items = items; xYWg1e$k
} -qndBS
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publicint getPageSize(){ wrt^0n'r)c
return pageSize; GGwHz]1L
} }>u<,
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publicvoid setPageSize(int pageSize){ MDKiwT@#
this.pageSize = pageSize; O_wRI\!
} Lv?e[GA
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publicint getTotalCount(){ Nl `8Kcv
return totalCount;
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} T8rf+B/.L
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publicvoid setTotalCount(int totalCount){ -( ,iwFb
if(totalCount > 0){ X>y6-%@
this.totalCount = totalCount; O(QJiS
int count = totalCount / /?P="j#u
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pageSize; #r_&Q`!eU
if(totalCount % pageSize > 0) 2r=A'
count++; & ]/Z~V t
indexes = newint[count]; oUwu:&<Orm
for(int i = 0; i < count; i++){ .AgD`wba
indexes = pageSize * |YAnd=$
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i; P7GF"/
} 4^O'K;$leD
}else{ aBLE:v
this.totalCount = 0; [!E8 C9Q#!
} 2x7%6'
} y$e'- v
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publicint[] getIndexes(){ `<L6Q2Y>j
return indexes; lU<n Wf
} ~\z\f}w
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publicvoid setIndexes(int[] indexes){ .Lk2S "+
this.indexes = indexes; qeyBZ8BG
} f`jRLo*L
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publicint getStartIndex(){ 5!PU+9Kh
return startIndex; e_BOzN~c
} J8"Cw<=O
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publicvoid setStartIndex(int startIndex){ 5[|MO.CB$
if(totalCount <= 0) V}>0r+NL<
this.startIndex = 0; P==rY5+s`
elseif(startIndex >= totalCount) .TURS
this.startIndex = indexes Z;_WU
ba 3_55]
[indexes.length - 1]; ^L;`F
elseif(startIndex < 0) :LL>C)(f
this.startIndex = 0; ,OLN%2Sq
else{ ~T')s-,l,:
this.startIndex = indexes L`ZH.fN
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[startIndex / pageSize]; C`D5``4
} L44-: 3
} 7 3k3(rZ
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publicint getNextIndex(){ t`DoTb4
int nextIndex = getStartIndex() + pbivddi2
@>J4K#"
pageSize; zb}:wUR
if(nextIndex >= totalCount) \)ac,i@fy
return getStartIndex(); 4
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else 6P'
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return nextIndex; ,c6ID|\
} #Vanw !
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publicint getPreviousIndex(){ X+{4,?04+
int previousIndex = getStartIndex() - LD WFc_
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pageSize; 6tM CpSJ
if(previousIndex < 0) :JSOj@s
return0; ~)}npS;
else @7%nMTZ@&v
return previousIndex; pd,5.d
} "}|n;:r
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} UGEC_
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抽象业务类 _ 9Tv*@
java代码: iy8UrgG;l
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/** O GrVy=rd
* Created on 2005-7-12 bxO8q57
*/ &M~*w~w`
package com.javaeye.common.business; :M1S*"&:
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import java.io.Serializable; c0u!V+V%
import java.util.List; y-{^L`%Mk
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import org.hibernate.Criteria; sW#6B+5_k
import org.hibernate.HibernateException; BULX*eOt
import org.hibernate.Session; ;&P%A<[`
import org.hibernate.criterion.DetachedCriteria; &?/h#oF@\
import org.hibernate.criterion.Projections; N/Z3 EF_
import |~CN]N
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org.springframework.orm.hibernate3.HibernateCallback; ?I`']|I
import 2Q)"~3
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org.springframework.orm.hibernate3.support.HibernateDaoS Z=
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upport; '
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import com.javaeye.common.util.PaginationSupport; g` 6Xrf
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public abstract class AbstractManager extends %?y ?rt
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HibernateDaoSupport {
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privateboolean cacheQueries = false; Lc f =)GL
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privateString queryCacheRegion; pcv (P
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publicvoid setCacheQueries(boolean $[6:KV
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cacheQueries){ A/,7%bB1
this.cacheQueries = cacheQueries; g9H~\w
} /);cl;"
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publicvoid setQueryCacheRegion(String kV(}45i]s
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queryCacheRegion){ !,+peMy
this.queryCacheRegion = +n %uIv
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queryCacheRegion; GNA:|x
} l&(,$RmYp
K~5QL/=1
publicvoid save(finalObject entity){ [iwn"e
getHibernateTemplate().save(entity); =da_zy
} Y5$5qQ
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publicvoid persist(finalObject entity){ t(-noy)
getHibernateTemplate().save(entity); &7!&]kA+
} Ka&[
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publicvoid update(finalObject entity){ %'nM!7w@I
getHibernateTemplate().update(entity); FylL7n
} @Nn9-#iW
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publicvoid delete(finalObject entity){ _|bIl%W;\'
getHibernateTemplate().delete(entity); %kS +n_*
} 9Ruj_U
w7$*J:{
publicObject load(finalClass entity, 2i;G3"\
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finalSerializable id){ hW$B;
return getHibernateTemplate().load ,`v)nwP
nPj%EKdY4
(entity, id); vcy}ZqWBO
} "~0m_brf
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publicObject get(finalClass entity, @tWyc%t
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finalSerializable id){ Xi^3o
return getHibernateTemplate().get s]Nh9h
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(entity, id); {O9CYP:
} ml <X92Y
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publicList findAll(finalClass entity){ ^E*W
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return getHibernateTemplate().find("from (=}cc
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" + entity.getName()); Kv^ez%I
} @.;] $N&J
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publicList findByNamedQuery(finalString zZ&L#
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namedQuery){ ~s{yh-B
return getHibernateTemplate j}7as&
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().findByNamedQuery(namedQuery); bwR_ uF
} d0$dQg
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publicList findByNamedQuery(finalString query, qq"&Bc>
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finalObject parameter){ "| 0g 1rd
return getHibernateTemplate ?K%&N99c!
kY*3)KCp
().findByNamedQuery(query, parameter); F(c~D0
} Pj9n`LwM
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publicList findByNamedQuery(finalString query, ~WXT0-,
[,[;'::=o4
finalObject[] parameters){ 6REv( E]
return getHibernateTemplate qplz !=
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().findByNamedQuery(query, parameters); =<mpZ'9gW
} [lZo'o
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publicList find(finalString query){ u3)Oj7cX
return getHibernateTemplate().find GWo^hIfJ
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(query); S-V)!6\cK
} CA%p^ 4Q
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publicList find(finalString query, finalObject 4np,"^c
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parameter){ 8:^`rw4a0
return getHibernateTemplate().find KNT(lA0s
q] g'rO'
(query, parameter); *#+e_)d
} E +\?|q !T
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public PaginationSupport findPageByCriteria ^9*FYV
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(final DetachedCriteria detachedCriteria){ `L p3snS
return findPageByCriteria YT7,=k _
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); 3GVE/GtU
} L4Ep7=
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public PaginationSupport findPageByCriteria -L e:%q2
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(final DetachedCriteria detachedCriteria, finalint ~5Wr
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startIndex){ ,Q|[Yr
return findPageByCriteria oFt]q
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(detachedCriteria, PaginationSupport.PAGESIZE, 7oY}=281
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startIndex); v%RcwVt|
} weQC9e~d{-
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public PaginationSupport findPageByCriteria TAz#e
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(final DetachedCriteria detachedCriteria, finalint g1U
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pageSize, o6f^DG3*
finalint startIndex){ oXw} K((|
return(PaginationSupport) O8BxXa@5
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getHibernateTemplate().execute(new HibernateCallback(){ x17cMfCH%
publicObject doInHibernate # Sfz^
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(Session session)throws HibernateException { {XYv&K
Criteria criteria = 9/Q_Jv-Q
bni :B?#
detachedCriteria.getExecutableCriteria(session); PMr
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int totalCount = `q Sfo`
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((Integer) criteria.setProjection(Projections.rowCount [
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n"B"Aysz
()).uniqueResult()).intValue(); uS :3Yo
criteria.setProjection :nki6Rkowt
q4_&C&7
(null); =x
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List items = +gb2>fei&
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criteria.setFirstResult(startIndex).setMaxResults c_b^t09
C[ <OF/
(pageSize).list(); hg7`jE&2
PaginationSupport ps = K~$o2a
e
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new PaginationSupport(items, totalCount, pageSize, .E:QZH' M
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startIndex); <Q)6N!Tp^
return ps; pE >~F
} ~ar8e
}, true); P\bW k p0
} ,ZjbbBZ
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public List findAllByCriteria(final l= 5kd.{
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DetachedCriteria detachedCriteria){ kK!An!9C
return(List) getHibernateTemplate Mj5=t:MI
jTk !wm=
().execute(new HibernateCallback(){ O6gI%Jdp
publicObject doInHibernate ^!H8"CdC3
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(Session session)throws HibernateException { 30]?Jz6m
Criteria criteria = UMUr"-l =
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detachedCriteria.getExecutableCriteria(session); R7cY$K{j
return criteria.list(); Uj}iMw,
} sAS\-c'6
}, true); Sj{z
} Bn*D<<{T
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public int getCountByCriteria(final dUeM+(s1
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DetachedCriteria detachedCriteria){ I"*g-ji0
Integer count = (Integer) 1g{`1[.QO
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getHibernateTemplate().execute(new HibernateCallback(){ %YefTk8cr,
publicObject doInHibernate 2Xk(3J!!'a
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(Session session)throws HibernateException { nab:y(]$/
Criteria criteria = 20;M-Wx
rs2~spN;h
detachedCriteria.getExecutableCriteria(session); Wfkm'BnV
return Lhu2;F\/
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criteria.setProjection(Projections.rowCount |{cdXbr
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()).uniqueResult(); KbVV[ *
} g"]%5Ow1
}, true); *ghkw9/
return count.intValue(); Zu:cF+hl
} Ta?#o
} t*y4)I !gR
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用户在web层构造查询条件detachedCriteria,和可选的 T^S|u8f
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 E*>tFw&[
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PaginationSupport的实例ps。 lYT}Nc4"="
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ps.getItems()得到已分页好的结果集 Qbfm*JP~
ps.getIndexes()得到分页索引的数组 k=H{gt
ps.getTotalCount()得到总结果数 IB
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ps.getStartIndex()当前分页索引 8,=Ti7_
ps.getNextIndex()下一页索引 e"hm|'
ps.getPreviousIndex()上一页索引 k!t5>kPSQ
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 G{}E~jDi?
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,尤其是上面的示例代码,让我着实觉得该对我原来的分页查询做 7xB#) o53
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一下代码重构了。 "v/^nH
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我把原本我的做法也提供出来供大家讨论吧: 3l->$R]
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首先,为了实现分页查询,我封装了一个Page类: ,!F'h:
java代码: ii2X7Q
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/*Created on 2005-4-14*/ ^=bJ
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package org.flyware.util.page; p]*$m=t0r
dP
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/** M3K+;-n^
* @author Joa .
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* \r^=W=
*/ Y<:%_]]
publicclass Page { i|Lir{vW
k<ku5U1|
/** imply if the page has previous page */ D(Zux8l
privateboolean hasPrePage; :RzcK>Gub=
Ig"Krz
/** imply if the page has next page */ "'94E,W
privateboolean hasNextPage; >wej1#\3
3Fo,F
/** the number of every page */ {F6hx9?
privateint everyPage; xE;4#+_I
(-(,~E
/** the total page number */ yC
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privateint totalPage; ?qAX *j
ppN96-]^0
/** the number of current page */ 7XT2d=)"
privateint currentPage; P-K\)65{Y
uh\I'
/** the begin index of the records by the current RQy|W}d_
j,/OzVm9
query */ +z+25qWi
privateint beginIndex; #E5Sc\,
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/** The default constructor */ Dgj`_yd
public Page(){ 9x ?" %b
92]>"
} g (ZeGNV8
cm%QV?
/** construct the page by everyPage }KCXo/y
* @param everyPage wHWd~K_q
* */ ?:s `}b
public Page(int everyPage){ /_xwHiA
this.everyPage = everyPage; 8~ .r/!wfy
} =9i:R!,W
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/** The whole constructor */ ~4=4Ks0
public Page(boolean hasPrePage, boolean hasNextPage, 702&E(rx,
UB|Nx(V s
k^ B'W{
int everyPage, int totalPage, g`y
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int currentPage, int beginIndex){ YMIDV-
this.hasPrePage = hasPrePage; @8DBLn w
this.hasNextPage = hasNextPage; W6K]jIQ
this.everyPage = everyPage; ym2\o_^(
this.totalPage = totalPage; rxI?|}4
this.currentPage = currentPage; fH`P8?](x
this.beginIndex = beginIndex; 2xni! *T+
} tJUMLn?
Cl\Vk
/** 4^w>An6
* @return *=MC+4E
* Returns the beginIndex. v8y77:
*/ 5[al^'y
publicint getBeginIndex(){ >
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return beginIndex; ~fAdOh
} NrgN{6u;
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/** .J%}ROm
* @param beginIndex e&8pTD3
* The beginIndex to set. f>\?\!
*/ :&2RV_$>=
publicvoid setBeginIndex(int beginIndex){ :QUZ 7^u
this.beginIndex = beginIndex; _66zXfM<
} *.Y!ZaK
:?@d\c'
/**
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* @return `;hsOfo
* Returns the currentPage. t<|=-
*/ ?.v!RdM+
publicint getCurrentPage(){ pk}*0Y-
return currentPage; Gw~^6( Qu
} |; $fy-
+;Q&
/** m3F.-KPO
* @param currentPage feIAgd},
* The currentPage to set. !g=,O6
*/ k#JFDw\
publicvoid setCurrentPage(int currentPage){ ^-~.L: }q
this.currentPage = currentPage; VXn]*Mo
} x\3 ` W
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/** =H>rX
2k
* @return > :!faWX
* Returns the everyPage. _AI2\e
*/ H<}<f:
publicint getEveryPage(){ 6xk"bIp
return everyPage; 70lb6A
} 6:-qL}
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/** KbMgatI/
* @param everyPage Z)P x6\?+
* The everyPage to set. _f|Au`7m
*/ K?-K<3]9f
publicvoid setEveryPage(int everyPage){ m?;)C~[
this.everyPage = everyPage; +**H7: bO
} "! p#8jR^
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/** %dw-}1X
* @return eff6=DP
* Returns the hasNextPage. )\`TZLR
*/ 0m7J'gm{
publicboolean getHasNextPage(){ bt%k;Z]
return hasNextPage; ,EcmMI^A
} Q`5jEtu#,
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/** eK/[jxNO
* @param hasNextPage Bwb3@vNA
* The hasNextPage to set. (G#)[0<fX
*/ 4mNL;O
publicvoid setHasNextPage(boolean hasNextPage){ p'KU!I}
this.hasNextPage = hasNextPage; e/#4)@]
} e)!X9><J
p7zHP
/** "^22Y}VB
* @return I4qzdD
* Returns the hasPrePage. &>L\unS
*/ $'?CY)h{
publicboolean getHasPrePage(){ |],{kUIXO
return hasPrePage; |I)xK@7
} mQVduG
7 &GhJ^Ku
/** dL6sb;7R
* @param hasPrePage .?!{. D
* The hasPrePage to set. }-:
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*/ &[R&@l Y
publicvoid setHasPrePage(boolean hasPrePage){ 6st(s@>
this.hasPrePage = hasPrePage; '~liDz*O
} wpx,~`&
F_YZV)q!W
/** ]y.,J
* @return Returns the totalPage. |06J4H~k
* Yk?uxZ4)H
*/ ;u}MG3Y8
publicint getTotalPage(){ mUcHsCszH
return totalPage; 1;.}u=8
} PeTA:MW
>tib21*
/** Axj<e!{D
* @param totalPage &/=xtO/Z{
* The totalPage to set. % fA0XRM
*/ -cY/M~
publicvoid setTotalPage(int totalPage){ {D`F$=Dlw
this.totalPage = totalPage; +/x|P-
} zx=A3I%7 A
#'$CC<*vy
} 2z )h,<D
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->8n.!F}
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上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 -pg7>vO q
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个PageUtil,负责对Page对象进行构造: r10)1`[
java代码: %[NefA(
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6"ZQN)7
/*Created on 2005-4-14*/ hrEKmRmF-
package org.flyware.util.page; Z [68ji]
W=F?+KgL
import org.apache.commons.logging.Log; "* 'rzd
import org.apache.commons.logging.LogFactory; >OiC].1
Y;-" Z
/** +k8><_vr}
* @author Joa xo^_;(;
* p9l&K/
*/ K")-P9I6-f
publicclass PageUtil { d*q_DV
9%\q*
privatestaticfinal Log logger = LogFactory.getLog 7p u*/W~
&yVii^
(PageUtil.class); `33h4G
3y 0`G8P'h
/** {d^&$~
* Use the origin page to create a new page @iWIgL
* @param page X)~JX}-L
* @param totalRecords eDTEy;^o
* @return rl4daV&,U
*/ yVh]hL#4+w
publicstatic Page createPage(Page page, int 8iX?4qj{P
$7|0{Dw
totalRecords){ TioI$?l>W(
return createPage(page.getEveryPage(), Q@]#fW\Y
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page.getCurrentPage(), totalRecords); /*D]4AK
} eJ7A.O
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/** '1.T-.4>&
* the basic page utils not including exception UN,@K9
>@TZYdl
handler E;-R<X5n
* @param everyPage J0|/g2%0
* @param currentPage j##IJm
* @param totalRecords 7CwG(c/5
* @return page ;Iv)J|*
*/ ]u2!)vZh'
publicstatic Page createPage(int everyPage, int $ n
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*W#x#0j
currentPage, int totalRecords){ zL)m!:_
everyPage = getEveryPage(everyPage); {f3T !e{
currentPage = getCurrentPage(currentPage); % YU(,83(+
int beginIndex = getBeginIndex(everyPage, wl5!f|
.sjM$#V=
currentPage); ? )0U!)tK
int totalPage = getTotalPage(everyPage, O'$:wc#
Fwho.R-.
totalRecords); Hyq|%\A
boolean hasNextPage = hasNextPage(currentPage, ~} wPiu,
roL~r`f`
totalPage); Mx$VAV^\
boolean hasPrePage = hasPrePage(currentPage); 5O*.qp?
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returnnew Page(hasPrePage, hasNextPage, (x?A#o>%
everyPage, totalPage, yrkd#m
currentPage, 9e8@0?0
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beginIndex); s u![ST(
} &)\0mpLK9
7{<t]wQq
privatestaticint getEveryPage(int everyPage){ eMWY[f3
return everyPage == 0 ? 10 : everyPage; PO |p53
} S>cT(q_&
"kf7??Z
privatestaticint getCurrentPage(int currentPage){ u5T\_0
return currentPage == 0 ? 1 : currentPage; GytI_an8
} V^?+|8_(
B.{0,bW?
privatestaticint getBeginIndex(int everyPage, int inR8m 4c]P
)`;?%N\
currentPage){ /mqEc9sq,
return(currentPage - 1) * everyPage; 5#WZXhlc}
} ilzR/DJ Ma
a)`h*P5@
privatestaticint getTotalPage(int everyPage, int c5O1h8
=B;rj
totalRecords){ Sy8o/-
int totalPage = 0; J,P7k$t2vv
&=_YL
if(totalRecords % everyPage == 0) dd98vVj
totalPage = totalRecords / everyPage; Kd^
._
else ]lm9D@HMC
totalPage = totalRecords / everyPage + 1 ; > `z^AB
sQTW?KA-Te
return totalPage; sA}=o.\j:
} -+O8v;aC'
{^$rmwN
privatestaticboolean hasPrePage(int currentPage){ 5n?fZ?6(
return currentPage == 1 ? false : true; AL,|%yup
} IjNE1b$
Y }e$5
privatestaticboolean hasNextPage(int currentPage, ;QW)tv.y
Nu|?s-
int totalPage){ mezP"N=L~
return currentPage == totalPage || totalPage == syBYH5
E-Cj^#OY|N
0 ? false : true; vW YN?"d
} 8 I,(\<Xv
<fN?=u+
[.|tD
} ]$KH78MTW
0'aZ*ozk
S(/@.gI:f
5E}0<&
H^'EY:|
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。 Q:@Y/4=
#YjV3O5<
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 9u"im+=:
ZLo3
0*
做法如下: rpy`Wz/[
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 I"Y?vj9]
?Yz.tg
的信息,和一个结果集List: D`,@EW].
java代码: w;{k\=W3Ff
a08B8
S.M< (
/*Created on 2005-6-13*/ */?L_\7
package com.adt.bo; OJ]{FI
)e]:T4*vo
import java.util.List; e`8z1r
M`iJ6L
import org.flyware.util.page.Page; 5C{X$7u
0*q~(.>a
/** Og-Mnx3
* @author Joa L'z?M]
*/ WV?iYX!
publicclass Result { bCA3w%,kM
>-+MWu=
private Page page; p|Z"<
I7p(
!A!zG)Ue<
private List content; JEFW}M)UGv
xAz gQ
/** h_y<A@[P}
* The default constructor
'6
w|z^
*/ [o|]>(tk
public Result(){ nLT]'B]$+
super(); b*.)m
} yf_<o
Rp. @
/** |%zhwDQ.
* The constructor using fields q_HD`tW
* |(y6O5Y.
* @param page V<ODt%
* @param content n>Zkx+jLj<
*/ REFisH-
public Result(Page page, List content){ 7_q"%xH
this.page = page; APK@Oq
this.content = content; Q"Q|]f*
} *4A.R&Vu
5dYIL`
/** !.3
MtXr
* @return Returns the content. I0)iC[s8;
*/ [iL2c=_
publicList getContent(){ :~6%nFo
return content; 1Rl`}7Km
} kv `x
vs6`oW"{#
/** 7B7I'{d
* @return Returns the page. UPJgTN*
*/ 8|yhe%-O
public Page getPage(){ R<JI
return page;
KJ'MK~g
} {L<t6A
DYzVV(_J"
/** q+)KY
* @param content d@#=cvW
* The content to set. :Z1_;`>CT
*/ (v(_XlMK
public void setContent(List content){ NK"y@)%0
this.content = content; a#G7pZX/I}
} O#u)~C?)8
. dM 0
/** Do2y7,jv
* @param page 2.; OHQTE
* The page to set. })&0e:6
*/ S93NsrBbY
publicvoid setPage(Page page){ Rzb663d
this.page = page; X>*zA?:
} QW~o+N~~
} gs0,-)
Z39^nGO
"gK2!N|#
Zz/w>kAG*{
xES+m/?KlZ
2. 编写业务逻辑接口,并实现它(UserManager, hpAIIgn
0*tEuJ7
UserManagerImpl) (<8T*Xo
java代码: ! '2'db
m=y6E,
_
lzxn} TO}
/*Created on 2005-7-15*/ EaP#~x
package com.adt.service; QP\vN|r
;gW~+hW ^
import net.sf.hibernate.HibernateException; 4tq>Lx^5U
7Y#b7H
import org.flyware.util.page.Page; w)!(@}vd
VN$#y4
import com.adt.bo.Result; poXkH@[O
B]]M?pS
/** .|iUDp6vz
* @author Joa 4["}U1sG
*/ !;R{-
publicinterface UserManager { qBCZ)JEN#U
yK}#|b'cM
public Result listUser(Page page)throws 59EAqz[:
tX)]ZuEi$
HibernateException; mTs[3opg
m{V@Om
} |
sQ5`lV?
-Mv`|odY/
Z2
t0l%
$@K+yOq+u
9_TZ;e
java代码: <-lz_
Xf#;GYO|2
uIWCVR8`Y
/*Created on 2005-7-15*/ G`)I _uO
package com.adt.service.impl; s';jk(i3
Dnd
import java.util.List; R'9TD=qEK
"M? (Ax
import net.sf.hibernate.HibernateException; *qq %)7
0~FX!1;
import org.flyware.util.page.Page; @l@lE0
import org.flyware.util.page.PageUtil; }>h?W1
YJ:CqTy
import com.adt.bo.Result; &Nec(q<
import com.adt.dao.UserDAO; *Qyw
_Q
import com.adt.exception.ObjectNotFoundException; gbI0?G6XN/
import com.adt.service.UserManager; ?j $z[_K
sN;U,{
/** ]cA){^.Jz
* @author Joa |Yk23\!
*/ }"3L>%Q5
publicclass UserManagerImpl implements UserManager { 73]%^kx=
;Y)?6^"
private UserDAO userDAO; pR~PB
5))?,YkrrI
/** Fd ]! 7
* @param userDAO The userDAO to set. &[kwM395
*/ P}aJvFlmP
publicvoid setUserDAO(UserDAO userDAO){ %r|fuwwJO
this.userDAO = userDAO; us5`?XeX]
} @NV$!FB<
!'PPj_Hp]
/* (non-Javadoc) a_pkUOu6
* @see com.adt.service.UserManager#listUser WM>9sJf
QtX ->6P>
(org.flyware.util.page.Page) (zTr/
*/ d B?I(
public Result listUser(Page page)throws 6o{anHBB
BD9` +9
HibernateException, ObjectNotFoundException { R;,&CQUl
int totalRecords = userDAO.getUserCount(); g3Ff<P P
if(totalRecords == 0) Kj'm<]u
throw new ObjectNotFoundException W'6*$Ron
Oys.8%+ P
("userNotExist"); 4; j#7
page = PageUtil.createPage(page, totalRecords); 9K)OQDv%6D
List users = userDAO.getUserByPage(page); }3vB_0[r
returnnew Result(page, users); ;rk}\M$+
} fHwh6|
bz<wihZj
} 6,oi(RAf
iVmf/N@A|
( XE`,#
# Dy;x\a
"\>
<UJ
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 :*4yR46
hJaqW'S
询,接下来编写UserDAO的代码: AbfLV942
3. UserDAO 和 UserDAOImpl: g#Yqw
java代码: 9]hc{\
qjTz]'^BpM
Lmj?V1% V
/*Created on 2005-7-15*/ y.mojx%?a
package com.adt.dao; >.M
`Fz.
T@k&YJ
import java.util.List; "I_3!Yu
%_A1WC
import org.flyware.util.page.Page; b_][Jye&P
(|bht 0
import net.sf.hibernate.HibernateException; `[Lap=.'.
U:8^>_
/** &Vl,x/
* @author Joa 7b
Gzun&
*/ 0MPsF{Xw[
publicinterface UserDAO extends BaseDAO { )vy<q/o+
{feS-.Khv
publicList getUserByName(String name)throws <2,@rYe/
}eB\k,7L
HibernateException; m,=$a\UC
BPi>SI0
publicint getUserCount()throws HibernateException; Zwq
uS9
vy-{BH
publicList getUserByPage(Page page)throws |5g*pXu{
B&L{/.v_z\
HibernateException; S%Ja:0=}?
#=$4U!yL
} )P|Ql-rE4
Up/1c:<J
WgY\m&
8t6h^uQ
R HF;AX n
java代码: s$Roe(J
'#q"u y
2%WZ-l!i
/*Created on 2005-7-15*/ 9:BGA/?
package com.adt.dao.impl; MTqbQ69v
ifBJ$x(B.
import java.util.List; GWP"i77y0s
H|,{^b@9
import org.flyware.util.page.Page; 5^%^8o
H ) (K
import net.sf.hibernate.HibernateException; ([$F5
q1TR
import net.sf.hibernate.Query; ]Q,RVEtKp
^,`Lt *
import com.adt.dao.UserDAO; .h*&$c/l
zpa'G1v
/** ";>D0h^D
* @author Joa 7s[ ATu
*/ X;}_[=-
public class UserDAOImpl extends BaseDAOHibernateImpl 2y<d@z:K
yp :yS
implements UserDAO { 4wNxn
lP
+rql7D0st
/* (non-Javadoc) 6XX5K@
* @see com.adt.dao.UserDAO#getUserByName tB1Qr**
2QBtwlQ?[
(java.lang.String) -(1e!5_-@
*/ b<[eBXe
publicList getUserByName(String name)throws -<<!eH
Z:n33xh=<
HibernateException { j5ui
String querySentence = "FROM user in class TbXZU$[c
_wX'u,HrC
com.adt.po.User WHERE user.name=:name"; r@n%
Query query = getSession().createQuery JLG5`{
IGI2).$[
(querySentence); * }2o
\h6Q
query.setParameter("name", name); j}ruXg
return query.list(); ~S=hxKI
} j#~4JGZt
LLU>c]a
/* (non-Javadoc) 61C&vm
* @see com.adt.dao.UserDAO#getUserCount() h?CNChRJs
*/ rhUZ9Fdv
publicint getUserCount()throws HibernateException { f,?7,? x
int count = 0; RGxOb
String querySentence = "SELECT count(*) FROM LB M:>d5
eM~i (]PY
user in class com.adt.po.User"; GvVuF S>y
Query query = getSession().createQuery ;N,7#l|wi
B
j*X_m
(querySentence); +~[19'GH
count = ((Integer)query.iterate().next T&0tW"r?
H?B.Hp|
()).intValue(); fmSA.z
return count; t>b^S,
} "iKK&%W
?s_q|d_
/* (non-Javadoc) Yhx~5p
* @see com.adt.dao.UserDAO#getUserByPage X'3F79`
g xLA1]>{
(org.flyware.util.page.Page) pFG~XW
*/ [Q%3=pm_
publicList getUserByPage(Page page)throws qI'a|p4fn?
!}vz_6)
HibernateException { J5l:_hZUV
String querySentence = "FROM user in class D)!k
:{Y,Nsa
com.adt.po.User"; WFh!re%Z
Query query = getSession().createQuery ?Dfgyz
c[;I\g
(querySentence); a-kU?&*
y
query.setFirstResult(page.getBeginIndex()) E@N_~1
.setMaxResults(page.getEveryPage()); Zwq_&cJK
return query.list(); *F9uv)[kz
} HWHGxg['r
"OWq]q#
} F4:ssy^
WM"I
r1
t[DXG2&
`9F'mT#o/
Eu0_/{:
至此,一个完整的分页程序完成。前台的只需要调用 Jl4zj>8~
}2{%V^D)r
userManager.listUser(page)即可得到一个Page对象和结果集对象 OgzPX^q/=
au#IA
的综合体,而传入的参数page对象则可以由前台传入,如果用 PmTA3aH
0ogTQ`2Z:
webwork,甚至可以直接在配置文件中指定。 ~+|p.(I
MbJV)*Q
下面给出一个webwork调用示例: ]6(NeS+
java代码: =?/J.[)<*
q,m6$\g4
>uI|S
/*Created on 2005-6-17*/ UyvFR@
package com.adt.action.user; w1.KRe{M
"V^(i%E;
import java.util.List; ]pFYAe ?
2'/ ip@
import org.apache.commons.logging.Log; x0 j$]$
import org.apache.commons.logging.LogFactory; H 7R1GaJ
import org.flyware.util.page.Page; ;[*7UE+#7
3s$m0
import com.adt.bo.Result; Iunt!L
import com.adt.service.UserService; *VD-c
import com.opensymphony.xwork.Action; sKNN ahGjh
;BpuNB
/** F*(<`V
* @author Joa 7$/ O{GBJ
*/ P,*R@N
publicclass ListUser implementsAction{ (m@({
xeZ,}YP)
privatestaticfinal Log logger = LogFactory.getLog rs<UWk<q
&a7KdGP8V
(ListUser.class); $Y>LUZ)b&8
S3.Pqp_<
private UserService userService; MQLa+I,S4
L0Xb^vx}m
private Page page; 3d
\bB !
^cX);koO
privateList users; R ]HHbD&;
++5SofG@
/* F~&bgl[YZ
* (non-Javadoc) 1?Wk qQ
* `@-H
;
* @see com.opensymphony.xwork.Action#execute() L`3 g5)V
*/ td%EbxJK]`
publicString execute()throwsException{ LzP+l>m
Result result = userService.listUser(page); YY'46
page = result.getPage(); ? !cUAa>iH
users = result.getContent(); MejM(o_kk
return SUCCESS; v2/@Pu!kg
} 4E<iIA\x
r+d%*Dx
/** 6-j><'
* @return Returns the page. &n91f
*/ FUiEayM
public Page getPage(){ YyjnyG
return page; FK{Vnj0
} hvwKhQ}wX
=c[9:&5Q
/** Fe{lM'
8
* @return Returns the users. y)C nH4{
*/ #2^eGhwnI
publicList getUsers(){ JPRo<jt=
return users; :bNqK0[rS
} D!^&*Ia?2
bXmX@A$#Io
/** M&wf4)*%0+
* @param page PuYAoKG
* The page to set. l`>|XUf6
*/ DQui7dr)l
publicvoid setPage(Page page){ S ( e]@
this.page = page; YHSdaocp
} +"
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k[#<=G_=/E
/** t<h[Lb%{T4
* @param users # 3UrGom
* The users to set. bys5IOP{]o
*/ -Ri/I4Xj
publicvoid setUsers(List users){ @komb IK
this.users = users; b\^X1eo
} ~}Xd{afo
ktF\f[
/** 1u>[0<U~E
* @param userService @$mh0K>
* The userService to set. \USl9*E
*/ ,58XLu
publicvoid setUserService(UserService userService){ lZ gX{
this.userService = userService; EC;R^)
} inQ1$
} ,!
b9
&lM=>?
g&&-
uE E;~`G
)@(IhU)
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, b,h@.s
+6~ut^YiM.
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 9t8NK{
z\7-v<ZS
么只需要: Z; 6N7U
java代码: xB:]{9r
80_}}op?8
W79Sz}):
<?xml version="1.0"?> pGRk
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork 7H])2:)
SL[ EOz#
1.0//EN" "http://www.opensymphony.com/xwork/xwork- \JLea$TM:
~v>3lEGn*
1.0.dtd"> He9Er
*q-VY[2
<xwork> HkPdqNC&
K0A[xkX6
<package name="user" extends="webwork- nPW=m`jG
R :*1Y\o(
interceptors"> X<sM4dwxE
<s=i5t
My5
<!-- The default interceptor stack name 2`^M OGYk
FJD;LpW
--> A$3ll|%j
<default-interceptor-ref VX:Kq<XwQ
:JXGgl<y
name="myDefaultWebStack"/> Z~AgZM
R
RF[Uy?es
<action name="listUser" 5fq4[a
~KYA{^`*
class="com.adt.action.user.ListUser"> 3~%M4(
<param <:>[24LJ{
)mH(Hx
name="page.everyPage">10</param> f"-3'kqo
<result bjBXs;zr@\
':|E$@$W
name="success">/user/user_list.jsp</result> $sFqMy
</action> .6c
Bx
2)Q%lEm`SP
</package> .U#oN_D
mtf><YU
</xwork> 5mX"0a_Q
q*!Vyk
,f~)CXNT?
s54AM]a{j
=j%ORD[
UNA!vzOb
这样就可以通过配置文件和OGNL的共同作用来对page对象设置初值 Et'&}NjI
8&:dzS
了。并可以通过随意修改配置文件来修改每页需要显示的记录数。 .[
s6x5M
4}t$Lf_
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 Lh-+i
ikb;,Js
mUfANlQ:
a|ZJzuqo
w&Z.rB?
我写的一个用于分页的类,用了泛型了,hoho F6ZL{2$k@
8w ]'U
java代码: / &em%/
0pBG^I`_
Cy5M0{
package com.intokr.util; ]V,#>'
nFjaV`6`@
import java.util.List; RijFN.s
L4<=,}KS
/** z>HM$n`YD
* 用于分页的类<br> 7Q|v5@;pU
* 可以用于传递查询的结果也可以用于传送查询的参数<br> l Ma||
* hdpA& OteR
* @version 0.01 '/fueku
* @author cheng vv D515i
*/ t?FPmbjv
public class Paginator<E> { yW;]J87*
privateint count = 0; // 总记录数 B7n1'?
privateint p = 1; // 页编号 AQs_(LR
privateint num = 20; // 每页的记录数 "4CO^ B
privateList<E> results = null; // 结果 [ak[ZXC,
{qFAX<{D
/** H6Kt^s<6xu
* 结果总数 w"!zLB&9[
*/ QKhvP>
publicint getCount(){ `o%Ua0x2
return count; 4x$Ts %]
} (y?`|=G-xT
Zv8G[(
publicvoid setCount(int count){ Ns-3\~QSi
this.count = count; KRh?{
} b$}@0
gal.<SVW
/** jxZd
=%7Q
* 本结果所在的页码,从1开始 "0 {t~?ol
* 5dhT?/qvc
* @return Returns the pageNo. vUgo)C#<
*/ k5)e7Lb(
publicint getP(){ M9wj
};vy
return p; **Q
K}j[D
} +WSM<