Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 ,GH`tK_
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 i\6CE|
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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 {nV/_o$$
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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 F"]P|
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分页支持类: Ljd`)+`D
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java代码: U=G49~E
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package com.javaeye.common.util; g0grfGo2p
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import java.util.List; ZIx-mC5
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publicclass PaginationSupport { XZIapT
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publicfinalstaticint PAGESIZE = 30; (!nkv^]
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privateint pageSize = PAGESIZE; }YDi/b7
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privateList items; 1tNL)x"w
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privateint totalCount; : .x((
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privateint[] indexes = newint[0]; eq6O6-
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privateint startIndex = 0; ~*iF`T6
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public PaginationSupport(List items, int zgAU5cw
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totalCount){ d)AYY}pw
setPageSize(PAGESIZE); 8TP$ ?8l
setTotalCount(totalCount); )=~&l={T
setItems(items); NpH8=H9
setStartIndex(0); [Fr](&Tx
} ~ n]5iGz
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public PaginationSupport(List items, int E'LI0fr
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totalCount, int startIndex){ qi,) l*?f
setPageSize(PAGESIZE); FHOw ]"#
setTotalCount(totalCount); y*iZ;Bv j
setItems(items); dOeM0_o
setStartIndex(startIndex); >G5aFk
} yvB]rz} i
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public PaginationSupport(List items, int @Go_5X(
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totalCount, int pageSize, int startIndex){ Ms!EK
setPageSize(pageSize); ws0qwv#
setTotalCount(totalCount); ?6:qAFw
setItems(items); sq'm)g
setStartIndex(startIndex); kOQ)QX
} k+h}HCzE
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publicList getItems(){ U<j5s\Y,
return items; lCU clD
} & &}_[{fc
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publicvoid setItems(List items){ h[remR#3\
this.items = items; PF~@@j
} kk=n&M
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publicint getPageSize(){ k$kE5kh,S
return pageSize; HgQjw!
} !eyLh&]5
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publicvoid setPageSize(int pageSize){ FSEf0@O:
this.pageSize = pageSize; W> pe-
} JqzoF}WH
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publicint getTotalCount(){ f-F=!^.
return totalCount; =0cTct6\
} OR@
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publicvoid setTotalCount(int totalCount){ 8T3,56>
if(totalCount > 0){ _BewaI;w
this.totalCount = totalCount; ..`c# O&
int count = totalCount / %L.S~dN6
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pageSize; OWvblEBF
if(totalCount % pageSize > 0) ^?lpY{aa
count++; KTm^}')C8
indexes = newint[count]; Cv,WG]E7(
for(int i = 0; i < count; i++){ >eGg 1
indexes = pageSize * bbC@
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} @8W@I|
}else{ #&|"t<}
this.totalCount = 0; H:(B^uH
} M1Q&)am
} "uBnK!
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publicint[] getIndexes(){ +p\E%<uQ
return indexes; ;?Pz0,{h
} 1n`[D&?q
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publicvoid setIndexes(int[] indexes){ 6{+yAsI
this.indexes = indexes; L2VwW
} fJLl-H
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publicint getStartIndex(){ Mk*4J]PP
return startIndex; )la3GT*1mS
} RE t&QP
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publicvoid setStartIndex(int startIndex){ :BxO6@>Xc
if(totalCount <= 0) H1-DK+Q:
this.startIndex = 0; BwHJr(n
elseif(startIndex >= totalCount) .B`$hxl*0c
this.startIndex = indexes S|=)^$:
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[indexes.length - 1]; =CQfs6np:N
elseif(startIndex < 0) VD.TosVeWo
this.startIndex = 0; MXSD8]je
else{ g(&cq
this.startIndex = indexes H>+/k-n-
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[startIndex / pageSize]; UuIjtqW
} .<t {saToU
} )>ff"| X
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publicint getNextIndex(){ <J^5l0)q
int nextIndex = getStartIndex() + \6
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pageSize; 8O^x~[sQ
if(nextIndex >= totalCount) >M5}L<
return getStartIndex();
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else J^"_H:1[
return nextIndex; *9n[#2sM<
} C@-Hm
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publicint getPreviousIndex(){ [],[LkS
int previousIndex = getStartIndex() - EeYL~ORdi
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pageSize; URVW5c
if(previousIndex < 0) >)K3
return0; !/}4_s`,
else /o4_rzR?
return previousIndex; UA.Tp [u
} s~,!E
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} yD<#Q\,
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抽象业务类 jZIT[HM
java代码: cs2-jbRn
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/** 7}xQ4M\u$
* Created on 2005-7-12 :awa
*/ }e7/F[c.U
package com.javaeye.common.business; 1'~+.92Y
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import java.io.Serializable; i<S\x
import java.util.List; -(57C*#ap
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import org.hibernate.Criteria; /,:cbpHsu
import org.hibernate.HibernateException; (B` NnL$
import org.hibernate.Session; NL.3qx
import org.hibernate.criterion.DetachedCriteria; ok--Jyhv#
import org.hibernate.criterion.Projections; l4kqz.Z-g
import !wAnsK
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org.springframework.orm.hibernate3.HibernateCallback; _
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import dZ|bw0~_!
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org.springframework.orm.hibernate3.support.HibernateDaoS tLJ 7tnB
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upport; 6 w!qZ4$
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import com.javaeye.common.util.PaginationSupport; p!DdX
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public abstract class AbstractManager extends nILUo2e~
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HibernateDaoSupport { R]od/u/$
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{
privateboolean cacheQueries = false; xD7Y"%Pbx
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privateString queryCacheRegion; P3bRv^
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publicvoid setCacheQueries(boolean Iv7BIK^0
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cacheQueries){
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this.cacheQueries = cacheQueries; "QfF]/:
} O0^Y1l
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publicvoid setQueryCacheRegion(String \(Dm\7Q.
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queryCacheRegion){ 'o]}vyz;
this.queryCacheRegion = CNiJuj`
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queryCacheRegion; uF,%N
} OwC{ Ad{
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publicvoid save(finalObject entity){ I<lkociUCG
getHibernateTemplate().save(entity); @)ozgs@e
} K(mzt[n(
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publicvoid persist(finalObject entity){ 1\f8-:C
getHibernateTemplate().save(entity); NnZ_x>R
} .R+n}>+K
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publicvoid update(finalObject entity){ iaJN~m\
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getHibernateTemplate().update(entity); ^oHK.x#{
} p'SY 2xq-,
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publicvoid delete(finalObject entity){ mpCKF=KL.
getHibernateTemplate().delete(entity); mnMY)-6C
} #|xj*+)H
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publicObject load(finalClass entity, z81`Lhg6
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finalSerializable id){ wd:SBU~f5*
return getHibernateTemplate().load vP<8,XG
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(entity, id); !ImtnU}
} G_p13{"IM
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publicObject get(finalClass entity, C"}]PW
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finalSerializable id){ IW|1)8d
return getHibernateTemplate().get yw?UA
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(entity, id); 9/GC8*+
}
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publicList findAll(finalClass entity){ g|3FJA/
return getHibernateTemplate().find("from Yv;18j*<
rUF= uO(
" + entity.getName()); v/Ei0}e6~
} !U+XIr
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publicList findByNamedQuery(finalString 'v3>"b
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namedQuery){ b~;+E#[*
return getHibernateTemplate a
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().findByNamedQuery(namedQuery); {wfe!f
} [.iz<Yh
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publicList findByNamedQuery(finalString query, t5za$kW'&
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finalObject parameter){ ;lo!o9`<
return getHibernateTemplate [318Q%W&
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().findByNamedQuery(query, parameter); PT`gAUCw
} l7JY`x
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publicList findByNamedQuery(finalString query, w+owx(mN@
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finalObject[] parameters){ U,u\o@3A
return getHibernateTemplate *XlnEHv
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().findByNamedQuery(query, parameters); <[GkhPfZ
} -i?-Xj#%
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publicList find(finalString query){ S(*SUH
return getHibernateTemplate().find )b AcU
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(query); &P{[22dQ
} O}#h^AU-BS
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publicList find(finalString query, finalObject F.JvMy3
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parameter){ 5 eWGX
return getHibernateTemplate().find A|d(5{:N
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(query, parameter); Fn!kest
} ebS>_jD
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public PaginationSupport findPageByCriteria p9)'nU'\t
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(final DetachedCriteria detachedCriteria){ e[7n`ka
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return findPageByCriteria Xj<B!Wn*Xb
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); v 5GV"qY
} 9IC|2w66
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public PaginationSupport findPageByCriteria h>+,ba"D
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(final DetachedCriteria detachedCriteria, finalint /u8m|S<
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startIndex){ y++[:M
return findPageByCriteria 2 -uL
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(detachedCriteria, PaginationSupport.PAGESIZE, i7f/r.
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startIndex); Xo>P?^c4?
} #yv_Eb02
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public PaginationSupport findPageByCriteria KZw"?%H[
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(final DetachedCriteria detachedCriteria, finalint >8nRP%r[5,
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pageSize, x%JtI'sg
finalint startIndex){ G~I@'[ur
return(PaginationSupport) IgOo2N"^l
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getHibernateTemplate().execute(new HibernateCallback(){ :YU_ \EV
publicObject doInHibernate Xj&fWuA
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(Session session)throws HibernateException { z5v)~+"1
Criteria criteria = 7N/v
Nj_h+=UE!
detachedCriteria.getExecutableCriteria(session); Z`23z(+
int totalCount = 54w..8'
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((Integer) criteria.setProjection(Projections.rowCount dhW)<
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()).uniqueResult()).intValue(); dw8Ce8W
criteria.setProjection uFIr.U$V
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(null); @O/-~,E68
List items = %W=S*"e-
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criteria.setFirstResult(startIndex).setMaxResults >v9 ("
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(pageSize).list(); bBBW7',[a
PaginationSupport ps = f YR*B0tu
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new PaginationSupport(items, totalCount, pageSize, jX79Nm|
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startIndex); YT6<1-E#
return ps; %SL'X`j
} cbD&tsF
}, true); N*N@wJy:5
} @JS O=8
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public List findAllByCriteria(final ON|Bpt2Qp
: uglv6
DetachedCriteria detachedCriteria){ Rdd[b?
return(List) getHibernateTemplate y-gSal
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().execute(new HibernateCallback(){ V^WR(Q}
publicObject doInHibernate TpLlbsd
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(Session session)throws HibernateException { F'DO46
Criteria criteria = X|)Ox
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detachedCriteria.getExecutableCriteria(session); hmv"|1Sa!~
return criteria.list(); Iq`:h&'!L
} f\FubL
}, true); 9pD=E>4?#
} uI^E9r/hB
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public int getCountByCriteria(final qh!2dj
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DetachedCriteria detachedCriteria){ mdW8RsR
Integer count = (Integer) V8w!yc
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getHibernateTemplate().execute(new HibernateCallback(){ 6H,n?[zTt
publicObject doInHibernate L,L>cmpM
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(Session session)throws HibernateException { xwr<ib:
Criteria criteria = i>w'$ {
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detachedCriteria.getExecutableCriteria(session); !N- -
return &)@|WLW
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criteria.setProjection(Projections.rowCount :gMcl"t--
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()).uniqueResult(); M}E0Msq_o
} A`x_M!m
}, true); SR@yG:~
return count.intValue(); 8y5iT?.~vy
} 3VZeUOxY\W
} s*.CJ
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用户在web层构造查询条件detachedCriteria,和可选的 #;59THdtPk
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 ;v0M
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PaginationSupport的实例ps。 QZ!;` ?(
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ps.getItems()得到已分页好的结果集 #?/&H;n_8S
ps.getIndexes()得到分页索引的数组 RO(~c-fV
ps.getTotalCount()得到总结果数 f$vWi&(
ps.getStartIndex()当前分页索引 e|)6zh<O:
ps.getNextIndex()下一页索引 >CtT_yhx
ps.getPreviousIndex()上一页索引
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 /,v>w,
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,尤其是上面的示例代码,让我着实觉得该对我原来的分页查询做 %$K2$dq5
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一下代码重构了。 #-b0U[,.
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我把原本我的做法也提供出来供大家讨论吧: AnK-\4
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首先,为了实现分页查询,我封装了一个Page类: jiS|ara"
java代码: tHlKo0S$0
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/*Created on 2005-4-14*/ XRi/O)98o
package org.flyware.util.page; X2>qx^jT
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/** t?JY@hT*
* @author Joa [C)JI; \
* ,MkldCV
*/ K:Mm?28s
publicclass Page { (#6E{@eq
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/** imply if the page has previous page */ NHKIZx8sR
privateboolean hasPrePage; kkfwICBI
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/** imply if the page has next page */ 9GdQ$^m
privateboolean hasNextPage; %YjZF[P
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/** the number of every page */ FwU*]wx|{
privateint everyPage; gY'w=(/`
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/** the total page number */ B^'Uh+Y
privateint totalPage; x|B$n} B
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/** the number of current page */ 3,qq\gxB
privateint currentPage; ^zjQ(ca@"x
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/** the begin index of the records by the current @Y2"=QVt
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query */ V. sIiE
privateint beginIndex; ~I^}'^Dbb
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/** The default constructor */ {4u8~whLp
public Page(){ d0(GE4+/
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} q0Rd^c
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/** construct the page by everyPage !_{2\&
* @param everyPage 4}nsW}jCc
* */ yxfV|ox
public Page(int everyPage){ qucw%hJ r
this.everyPage = everyPage; `? ayc/TK
} 1S!<D)n
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/** The whole constructor */ 4{2)ZI#
public Page(boolean hasPrePage, boolean hasNextPage, " bHeNWZ
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int everyPage, int totalPage, @D.]PZf
int currentPage, int beginIndex){ 1iOQ8hD
this.hasPrePage = hasPrePage; Mp;yvatO
this.hasNextPage = hasNextPage; .BLF7>
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this.everyPage = everyPage; fneg[K
this.totalPage = totalPage; I"*;fdm
this.currentPage = currentPage; }@Mx@ S
this.beginIndex = beginIndex;
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} D8+68_BEM
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/** G$\2@RT9[
* @return BV=L.*
* Returns the beginIndex. LM_/:
*/ Pw4j?pv2
publicint getBeginIndex(){ u*R9x3&/5
return beginIndex; pa0'\
} F +e
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/** yK"OZ2Mv
* @param beginIndex I0\}S [+H
* The beginIndex to set. -"L)<J@gQ?
*/ D7Y5q*F
publicvoid setBeginIndex(int beginIndex){ <&'Y e[k
this.beginIndex = beginIndex; QC:/xP
} {Kp<T
PPCZT3c=
/** Uk5O9D0
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* @return 5- Q`v/w;
* Returns the currentPage. H!dUQ
*/ MxiU-
publicint getCurrentPage(){ ailje
return currentPage; dvUBuY^[
} jjgY4<n
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/** [0GM!3YJ7
* @param currentPage l'~]8Wo1
* The currentPage to set. #80*3vi~F
*/ zT}Q rf~
publicvoid setCurrentPage(int currentPage){ :=#*[H
this.currentPage = currentPage; EXz5Rue
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} I>b-w;cC
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/**
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* @return kP%Hg/f/Ot
* Returns the everyPage. DI=Nqa)r
*/ HF-Msu6
publicint getEveryPage(){ 8uME6]m
i
return everyPage; @URLFMFi
} nbYkr*: "t
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/** FAu G`zu
* @param everyPage an3HKfv
* The everyPage to set. T6f{'.w
*/ 6Rn_@_Nn)f
publicvoid setEveryPage(int everyPage){ $;*YdZ`q
this.everyPage = everyPage; l79jd%/m
} n<:/ X tE
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/** zOq~?>Ms6
* @return )@Yp;=l
* Returns the hasNextPage. f}bUuQrH-!
*/ ]>@;
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publicboolean getHasNextPage(){ l;>#O
return hasNextPage; Co8b0-Z
} 5| 2B@6-
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/** ~MY7Ic%
* @param hasNextPage aDa}@-F&a
* The hasNextPage to set. &sL5Pt_
*/ z]>aWH}$
publicvoid setHasNextPage(boolean hasNextPage){ a34'[R
this.hasNextPage = hasNextPage;
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} 2]NP7Ee8Z
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/** =ox#qg.5
* @return ^ j@Q2>&?
* Returns the hasPrePage. Kq`Luf
*/ |bDN~c:/
publicboolean getHasPrePage(){ K G~](4JE(
return hasPrePage; O#A1)~
} S6H=(l58
.Gl&K|/{j
/** :5?ti
* @param hasPrePage tBG :ECUL
* The hasPrePage to set. $XFG1?L!
*/ 49
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publicvoid setHasPrePage(boolean hasPrePage){ u0$7k9mE
this.hasPrePage = hasPrePage; sXTt)J
} \{da|n-
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/** ZP?k |sEH
* @return Returns the totalPage. c}mJ6Pt
* :LVM'c62c>
*/ &+`l
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publicint getTotalPage(){ U6X~]| o
return totalPage; xpyb&A
} *NV`6?o@6
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/** w;QDQ
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* @param totalPage $E|W|4N
* The totalPage to set. |d D! @K
*/
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publicvoid setTotalPage(int totalPage){ 3HbHl?-UNU
this.totalPage = totalPage; Xkl^!,
} 4PiN Q'*
o;Zoj}
} ,-CDF)~G=3
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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 T9Vyj3!i_
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个PageUtil,负责对Page对象进行构造: ENC_#-1x
java代码: =(v!pEF
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/*Created on 2005-4-14*/ DHt 8 f
package org.flyware.util.page; zwU8i VDe
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import org.apache.commons.logging.Log; ?
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import org.apache.commons.logging.LogFactory; d?N"NqaN
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/** H.idL6*G
* @author Joa P+}qaup
* q'(WIv@
*/ (dMFYL>YP
publicclass PageUtil { -(cm
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privatestaticfinal Log logger = LogFactory.getLog &K>]!yn
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(PageUtil.class); 1A E/ILGo
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/** F5
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* Use the origin page to create a new page iqy}|xAU
* @param page +crAkb}i
* @param totalRecords `zzX2R Je
* @return mApn(&
*/ x(]s#D!)
publicstatic Page createPage(Page page, int ,xD{A}}V
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totalRecords){ e_1mO 5z
return createPage(page.getEveryPage(), 1
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page.getCurrentPage(), totalRecords); CPVKz
} VdeK~#k
$#RD3#=?u
/** j%p~.kW5
* the basic page utils not including exception rG\m]C3 E
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handler m/eGnv;!
* @param everyPage On'3K+(_
* @param currentPage :ZL>JVk
* @param totalRecords Vj2GK"$v
* @return page r`;C9#jZ
*/ Z$ftG7;P0
publicstatic Page createPage(int everyPage, int g~B@=R
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currentPage, int totalRecords){ vhL&az
everyPage = getEveryPage(everyPage); ^F" *;8$
currentPage = getCurrentPage(currentPage); G0Wd"AV+
int beginIndex = getBeginIndex(everyPage, zl:
u@!'
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currentPage); Y43#];
int totalPage = getTotalPage(everyPage, LV]\{'
a^=4'.ok
totalRecords); l4/TJ%`MG
boolean hasNextPage = hasNextPage(currentPage, e< CPaun
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totalPage); Q}=RG//0*
boolean hasPrePage = hasPrePage(currentPage); [CUJ A
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returnnew Page(hasPrePage, hasNextPage, 19N:9;Ixz
everyPage, totalPage, Bw_Ih|y,w
currentPage, J:(Shd'4D
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beginIndex); ]Ea7b
} JxLH]1b
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privatestaticint getEveryPage(int everyPage){ 6pLwwZD
return everyPage == 0 ? 10 : everyPage; f%|S>(
} }oN(nPxv9
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privatestaticint getCurrentPage(int currentPage){ I2W2B3D` c
return currentPage == 0 ? 1 : currentPage; Vks,3$
} NDg]s2T
J<BdIKCma
privatestaticint getBeginIndex(int everyPage, int [e}]K:
ky~ x4_y5
currentPage){ &(rd{j/*
return(currentPage - 1) * everyPage; }w-`J5Eq#
} >bZ#
Tb)x8-0
privatestaticint getTotalPage(int everyPage, int {30<Vc=
CYn}wkz
totalRecords){ c|.:J]
int totalPage = 0; 0sUc6_>e
<Z__Q
if(totalRecords % everyPage == 0) rL
s6MY
totalPage = totalRecords / everyPage; B_&PK7vA
else v'>Yc#VJ
totalPage = totalRecords / everyPage + 1 ; E, v1F!
l3afuD:
return totalPage; m[bu(q z
} V")Q4h{
<=-\so(
privatestaticboolean hasPrePage(int currentPage){ J6%op{7/
return currentPage == 1 ? false : true; 9@1W= sl
} UA9LI<Y
M[{Cy[ta
privatestaticboolean hasNextPage(int currentPage, 7_3O]e[8
"J.jmR;
int totalPage){ P
X0#X=$
return currentPage == totalPage || totalPage == }dHiW:J>
u#,]>;
0 ? false : true; 6~8
RFf"
} G6,8Xwk
]Bsq?e^
.UYpPuAkn
} w7D:0SGD
</=PN1=A
H<xC%/8
mTPj@F>
\nHlI=!P
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。 :A'!u r=\
<S}qcjG
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 sy?>e*-{
!kcg#+s91
做法如下: .'a |St
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 mr1}e
VM~!
GWVdNYpmr
的信息,和一个结果集List: d!t@A
java代码: (FaT{W{
H_j<%VW
_+N^yw ,r*
/*Created on 2005-6-13*/ Pc7:hu
package com.adt.bo; p~.@8r(
yq}{6IyZ^
import java.util.List; RI(uG-Y
~ YK<T+
import org.flyware.util.page.Page; `Z/ IW
9CNHjs+-}s
/** K_5&_P1
* @author Joa IebS~N
E
*/ 5);#\&B
publicclass Result { gJ&!w8v.
*[H+8/n_
private Page page; %RN-J*s]
ay_D.gxz
private List content; #H[4?4r
_PM<25Y,@
/** Q
8rtZ
* The default constructor Fsf22
*/ qX(%Wn;n
public Result(){ o
x^lI
super(); aAri
} /;rN/ot2o
\V>%yl{8
/** 2eU[*x
* The constructor using fields f}X8|GlBo
* m-8 9nOls
* @param page 5E!m! nBZ
* @param content B`scuLl3
*/ qN[7zsaj
public Result(Page page, List content){ N%f!B"NQ
this.page = page;
nvPE
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this.content = content; D-GU"^-9
} =%\6}xPEl<
YfwJBzD
/** ql~{`qoD~
* @return Returns the content. t^,Qy.L0
*/ ik*)j
publicList getContent(){ tb0E?&M
return content; ;8iL,^.A
} el?V2v[
&a_kJ)J
/** Z9&D'n)
* @return Returns the page. ig}e@]
*/ V;-.38py
public Page getPage(){ 3DAGW"F
return page; 03QEXm~|Q
} (L0hS'
5Vqmv<F;$Z
/**
#
5f|1O
* @param content \ ~LU 'j
* The content to set. sMfFm@\ N
*/ !UBDx$]^
public void setContent(List content){ P"=UI$HN
this.content = content; L_gsG|xX
} kh?#={]Z
2rj/wakd
/** `F2*o47|t
* @param page eY4`k
* The page to set. /SCZ&
*/ StyB"1y
publicvoid setPage(Page page){ V"7<[u]K|
this.page = page; HhWwc#B
} ?BDlB0jxzi
} xV,4U/T
g^z5fFLg/8
Lf;
ta
-yl4tW
!qTpQ5Dm
2. 编写业务逻辑接口,并实现它(UserManager, 8L7Y
A)u
Pu$kj"|q*[
UserManagerImpl) o0aO0Y
java代码: hB
P$9GR
E?Qz/*'zv
-t%{"y
/*Created on 2005-7-15*/ ~jp!"f
package com.adt.service; ^J#?hHz
qXrt0s[
import net.sf.hibernate.HibernateException; 0NCOz(L/
~{7zm"jN
import org.flyware.util.page.Page; vLv|SqD
lruF96C/Y
import com.adt.bo.Result; &547`*
j}rgOz.
/** R<n8M"B
* @author Joa 4i_spF-3
*/ ;g:
U[cE
publicinterface UserManager { n0+g]|a
AF
,zAK3d&hj
public Result listUser(Page page)throws 5T$}Oy1
jw/'*e
HibernateException; K/f>f; c
$i,6B9
} pau*kMu^}
g(-;_j!=
hH<6E
B;xZ%M]
cm@jt\D
java代码: TqS2!/jp
rnnX|}J
c@RT$Q9j
/*Created on 2005-7-15*/ &_"ORqn&
package com.adt.service.impl; WW//heJe-
OZ(Dpx(Q
import java.util.List; M0cd-Dn
#d7N| 9_
import net.sf.hibernate.HibernateException; u|(Ux~O
FWuw/b$
import org.flyware.util.page.Page; kcLj Kp
import org.flyware.util.page.PageUtil; P7's8KOoS
1i4WWK7k
import com.adt.bo.Result; yJDeX1+,
import com.adt.dao.UserDAO; /3J z3
import com.adt.exception.ObjectNotFoundException; f=t:[<
)
import com.adt.service.UserManager; 7)B&(2D&
x1t{SQ-C
/** !cRfZ
* @author Joa 8{R&EijC
*/ ?TIV2m^?
publicclass UserManagerImpl implements UserManager { w?kGi>7E
[dl+:P:zc
private UserDAO userDAO; Ee{ `Y0
i~9?:plS
/** }P#Vsqe V
* @param userDAO The userDAO to set. J4YT)-
*/ *R5`.j =
publicvoid setUserDAO(UserDAO userDAO){ t(}/g
this.userDAO = userDAO; A[RHw<
} GHv{
py]KTRzy
/* (non-Javadoc) Dt
W*n1Bt
* @see com.adt.service.UserManager#listUser `&7mHa61
#"::
'?,
(org.flyware.util.page.Page) q<n[.u1@
*/ ;xfO16fNk
public Result listUser(Page page)throws cI2Fpf`2Wj
ovo/!YJ2
HibernateException, ObjectNotFoundException { G@9u:\[l
int totalRecords = userDAO.getUserCount(); 5B1G?`]?
if(totalRecords == 0) NeHx2m+
throw new ObjectNotFoundException BYS lKTh
Vr 8:nP:
("userNotExist"); a>U6Ag<
page = PageUtil.createPage(page, totalRecords); ,"B?_d6
List users = userDAO.getUserByPage(page); (4~X}:
returnnew Result(page, users); Mal <iNN
} ba8 6 N
,I ZqLA
} .hKhrcQp
a.?v*U@z@#
~F;CE"3A
?KCivf
{J2#eiF
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 Zb."*zL
U2bzUxK
询,接下来编写UserDAO的代码: .l\r9I(
3. UserDAO 和 UserDAOImpl: $ADPV,*gG
java代码: "qawq0P8Z
7Re-5vz
R
w#&z]O9r
/*Created on 2005-7-15*/ COSTV>s;
package com.adt.dao; JT04vm4
Y.>kO
import java.util.List; dByjcTPA
\ZMP_UU(
import org.flyware.util.page.Page; Z ] '>
r?pZ72q
import net.sf.hibernate.HibernateException; 1SUzzlRx
ll%G!VR
/** sm
* @author Joa )|pU.K9qZ
*/ JdiP>KXV
publicinterface UserDAO extends BaseDAO { Yrxk Kw#
LKx` v90p
publicList getUserByName(String name)throws fJy)STQ4
.#0H{mk
HibernateException; 'd/*BjNp)
9*\g`fWc}{
publicint getUserCount()throws HibernateException; 0oSQY[ht/
p>q&&;fe
publicList getUserByPage(Page page)throws n3$gx,KL
GF'f[F6oI
HibernateException; ? Vp%=E
)Q]w6he3
} qBYg[K>
Jt]&;0zn2
SNab
zJY']8ah
w>[T&0-N
java代码: >
H BJk:
s]Gd-j
.*Vkua
/*Created on 2005-7-15*/ B`{mdjMy
package com.adt.dao.impl; DtI$9`~
`*aBRwvK~
import java.util.List; Lc]1$
2JZdw
import org.flyware.util.page.Page; fQU{SjG
tuxRVV8l
import net.sf.hibernate.HibernateException; NEVp8)w
import net.sf.hibernate.Query; s?c JV`
5/?P|T
import com.adt.dao.UserDAO; @7W?8
qSTW b%
/** rslvsS:
* @author Joa jXp. qK\"
*/ c<4F4k7
public class UserDAOImpl extends BaseDAOHibernateImpl ?Vc0)
Uw)=WImz[
implements UserDAO { CxDcY
6+3 $:?
/* (non-Javadoc) jj,r <T
* @see com.adt.dao.UserDAO#getUserByName AbfZ++aJ
NYB "jKMk
(java.lang.String) . I==-|
*/ xE1'&!4O
publicList getUserByName(String name)throws Fp%Ln(/m
gn)R^
HibernateException { ){P^P!s$
String querySentence = "FROM user in class _ym"m,,7?
zkexei4^<
com.adt.po.User WHERE user.name=:name"; .'T 40=7
Query query = getSession().createQuery {kL&Rv%'
9S>g6}[E#0
(querySentence); +sf .PSz$
query.setParameter("name", name); !^WHZv4
return query.list(); S^N{wZo
} :( ,mL2[
fu4!t31
/* (non-Javadoc) 0V`[Zgf
* @see com.adt.dao.UserDAO#getUserCount() dv!r.
*/ ,j178EX
publicint getUserCount()throws HibernateException { ?djQZ*
int count = 0; opp!0:jS*
String querySentence = "SELECT count(*) FROM .Djta|puu
sgAzL
user in class com.adt.po.User"; XAuI7e
Query query = getSession().createQuery "=A>}q@;H
rs]I
(querySentence); HBiBv-=,
count = ((Integer)query.iterate().next ho.(v;
a#[-*ou`
()).intValue(); 3FNT|QF
return count; |=K_F3aJ
} "2{%JFE
I ~$1Lu`~
/* (non-Javadoc) VhEka#
* @see com.adt.dao.UserDAO#getUserByPage lH2wG2
x({C(Q'O
(org.flyware.util.page.Page) tR)H~l7q
*/ )D/ 6%]O
publicList getUserByPage(Page page)throws +Xy*?5E;C
2SG$LIV 9Y
HibernateException { J7+w4q~cB`
String querySentence = "FROM user in class A.En+-[\
314=1JbL
com.adt.po.User"; :a0zT#u
Query query = getSession().createQuery p|[B
=.c{
Q5a)}6-5
(querySentence); ig+4S[L~n
query.setFirstResult(page.getBeginIndex()) 9 OT,TpA
.setMaxResults(page.getEveryPage()); MX|H}+\
return query.list(); ,S&z<S_
} #hw>tA6
eu#'SXSC
F
} (zcLx;N
zpjqEEY;
z#6?8y2-
iG<Som
Jxl6a:
至此,一个完整的分页程序完成。前台的只需要调用 /)L
0`:I#
?cy4&]s
userManager.listUser(page)即可得到一个Page对象和结果集对象 @)6jE!LC
v]VWDT
`
的综合体,而传入的参数page对象则可以由前台传入,如果用 3V<&|
k G0Yh2;#
webwork,甚至可以直接在配置文件中指定。 1;F`c`0<
g(4bBa9y
下面给出一个webwork调用示例: [wnDHy6W
java代码: WyhhCR=;
%;"@Ah
23]Y<->Eu<
/*Created on 2005-6-17*/ Rl~T$
Ey
package com.adt.action.user; >SbK.Q@ei
6<76H
import java.util.List; jeUUa-zR3
F>hZ{
import org.apache.commons.logging.Log; G&f8n
import org.apache.commons.logging.LogFactory; r(A.<`\
import org.flyware.util.page.Page; ` uCI Xb
Vr.Y/3N&'
import com.adt.bo.Result; @R|'X
import com.adt.service.UserService; zCaT tb|@
import com.opensymphony.xwork.Action; "Zv~QwC
C~%
1w%nn
/** xg@NQI@7
* @author Joa 0MF}^"R
*/ 8hanzwoJ:
publicclass ListUser implementsAction{ w f.T3
8 .>/6M
privatestaticfinal Log logger = LogFactory.getLog ]b?9zeT*'l
!U%T&?E l
(ListUser.class); *XOJnyC_H
nAJdr*`a,5
private UserService userService; rZXrT}Xh{W
5*%#o
private Page page; k;W@LfP
6?tlU>A2s
privateList users; g`^X#-!(
B5%n(,Lx
/* {y= W6uP
* (non-Javadoc) uP $Cj
* @D^^_1~
* @see com.opensymphony.xwork.Action#execute() Bh`N[\r
*/ {=2DqkTD
publicString execute()throwsException{ rf:XRJ<4
Result result = userService.listUser(page); `>(W"^
page = result.getPage(); CbBSFKM
users = result.getContent(); q<W=#Sx
return SUCCESS; .jw}JJ
} Yj|eji7y
-/C)l)V}
/** `A$!]&[~|
* @return Returns the page. o Pci66
*/ h5_G4J{1
public Page getPage(){ *.-.iY.a]
return page; \`<cH#
} s'aip5P
OI1ud/>h
/** o{b=9-V
* @return Returns the users. /
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*/ gJiK+&8I
publicList getUsers(){ ^mWybPqx
return users; [H\:pP8t
} 7\zZpPDV
c
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/** AUVgPXOwd
* @param page Zv_.na/^K
* The page to set. eivtH P
*/ 1(Y7mM8\
publicvoid setPage(Page page){ W%2
80\h
this.page = page; )0vU
k
} 4(neKr5\#
unJid8Lo
/** -!;l~#K=
* @param users (6CN/A{qe
* The users to set. OdWou|Gz
*/ _I`,Br:N
publicvoid setUsers(List users){ q+KzIde|%
this.users = users; P&d"V<
} > oA?6x
XoLJ L]+?
/** FlfI9mm
* @param userService fJ\sguZ
* The userService to set. 9odJr]
*/ P1b'%
publicvoid setUserService(UserService userService){ N"/-0(9[
this.userService = userService; CycUeT
} `b8v1Os^2
} (>6*#9#p
>&g}7d%
nVu&/
SvN9aD1
d_n7k g+
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, !3iGz_y
6C>_a*w
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 e__@GBG
]sz3]"2
么只需要: Q%/<ZC.Mz6
java代码: ,\ 2a=Fp
^l^fD t
J$4wL
F3
<?xml version="1.0"?> H/M Au7
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork 6{[pou&
O3N0YGhJ
1.0//EN" "http://www.opensymphony.com/xwork/xwork- I$Qs;- (
5qg2Zc~
1.0.dtd"> +jg9$e "
JOjoiA
<xwork> 5Zmw} M
oLWJm
<package name="user" extends="webwork- i{!T&8
xD&^j$Em
interceptors"> Lb{e,JH
*Ype>x{
<!-- The default interceptor stack name @)kO=E d
DjU9
uZT
--> SVjl~U-^
<default-interceptor-ref Xi?b]Z
pE{yv1Yg
name="myDefaultWebStack"/> )$w*V9d
r'CM
<action name="listUser" Cv$
SJc
wU#F_De)R:
class="com.adt.action.user.ListUser"> f<+4rHT
<param bX.ja;;
@i^~0A#q*
name="page.everyPage">10</param> p^(&qk?ut
<result iv phlw
k OvDl!^
name="success">/user/user_list.jsp</result> :16P.z1L
</action> Z5c~^jL$-
UgWs{y2SE.
</package> h25G/`
IHgeQ F
~
</xwork> *lef=:&,,
,uzN4_7u
,>t69 Ad
|
ohL]7b<
T&86A\D\z
"x@='>:$
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 p8s:g~ W
"<}&GcJbz
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。 J 5h+s-'
&V|>dLT>A
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 5Z4-Z
Y(\T-
bI
)BfT7{WN
qQ!1t>j+H
Soie^$
Y
我写的一个用于分页的类,用了泛型了,hoho {0! ~C=P
bYz&P`o}
java代码: =AVgIv
:V2bS
6t/`:OZC:
package com.intokr.util; SI:U0gUc
9 Pw0m=4
import java.util.List; 1 T130L
0Z|FZGRP
/** pZ#ap<|>I
* 用于分页的类<br> v/ *Y#(X
* 可以用于传递查询的结果也可以用于传送查询的参数<br> 2<mW\$
* sH[
-W-
* @version 0.01 I\qYkWg7
* @author cheng K[chjp!$l
*/ !_2n
public class Paginator<E> { UpXz&k
privateint count = 0; // 总记录数 l!#m&'16"
privateint p = 1; // 页编号 Jc)^49Rf
privateint num = 20; // 每页的记录数 tNVV)C
privateList<E> results = null; // 结果 Y!6/[<r$~k
g'];Estb~
/** cI]WrI2CQa
* 结果总数 [![%9'+P
*/ PpLU
publicint getCount(){ VF&Z%O3n
return count; O4<g%.HC6
} Bx[rC
q9"=mO0J+
publicvoid setCount(int count){ &'l>rD^o
this.count = count; `:'w@(q
} Wlh~)
XPB9~::
/** :|o<SZ
* 本结果所在的页码,从1开始 kP xa7
* 9+,R`v
* @return Returns the pageNo. t6c<kIQ:-O
*/ v){ .Z^_C
publicint getP(){ jkiTj~WE-
return p; I8OD$`~*U6
} XWJwJ
( 6(x'ByT
/** E1;@=#t2i
* if(p<=0) p=1 q_
=b<.;
* e6=]m#O9
* @param p Y-ux7F{=z
*/ ]CU]pK?nq
publicvoid setP(int p){ "l={)=R
if(p <= 0) .kTG[)F0b
p = 1; 7^}Ll@
this.p = p; _ >`X]I;
} ,fEO>
i
T^Ab!O
/** J==SZ v
* 每页记录数量 !~_zm*CqbZ
*/ 2/,0iwj-
publicint getNum(){ lq.Te,Y%w
return num; i?Ss: v^
} <lr*ZSNY
7\o!HMfK
/** ThW,Y"
l
* if(num<1) num=1 2?@j~I=s2h
*/ dBO@6*N4c
publicvoid setNum(int num){ HG/p$L*
if(num < 1) f[gqT
yiP
num = 1; :5GZ \Z8F
this.num = num; v+6@cC
}
4eVI},
7dihVvL
$
/** W{XkVKe1a
* 获得总页数 s!/TU{8J
*/ ^"8G`B$r
publicint getPageNum(){ r%Rs0)$yj
return(count - 1) / num + 1; M8w5Ob
} C@o%J.9"#
Oc9#e+_&
/** }aB#z<B6
* 获得本页的开始编号,为 (p-1)*num+1 F?Ju??O
*/ 33:DH}
publicint getStart(){ ,1Qd\8N9
return(p - 1) * num + 1; b(GFMk
} 4^c-D
'#\D]5
/** QzGV.Mt2
* @return Returns the results. IL7`0cN(
*/ ,xJrXPW
publicList<E> getResults(){ ~E4"}n[3A#
return results; ?_6YtR,{
} zIQzmvf
HU
B|bKy
public void setResults(List<E> results){ ]kktoP|D
this.results = results; uK*Nu^
} cu#e38M&eE
'(@YK4_M
public String toString(){ ScnY3&rc
StringBuilder buff = new StringBuilder a7H0!9^h
Y5A~E#zw
(); bggusK<
buff.append("{"); { }e^eJ
buff.append("count:").append(count); w=r&?{
buff.append(",p:").append(p); t7#lsd`_
buff.append(",nump:").append(num); $]d*0^J 6
buff.append(",results:").append
#S
QXTR
!MZw#=D`
(results); <MD;@_Nz\
buff.append("}"); RcY[rnI6
return buff.toString(); 7-iIay1h"
} #Olg(:\
kv|,b
} vM0_>1nN
gqiXmMm:9
, j980/