Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 kv, !"<
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 /c 7z[|
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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 \~(kGE--+
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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 "#-iD
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分页支持类: A'b$X1h
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java代码: MSeg7/ MF
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package com.javaeye.common.util; 0GeL">v,:=
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import java.util.List; NH}o`x/
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publicclass PaginationSupport { g,M-[o=Fk
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publicfinalstaticint PAGESIZE = 30; js"5{w&
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privateint pageSize = PAGESIZE; &GJVFr~z
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privateList items; d|7LCW+HW
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privateint totalCount; VP^Yf_
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privateint[] indexes = newint[0]; = >tkc/aa
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privateint startIndex = 0; J5HK1
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public PaginationSupport(List items, int 3&AJN#c
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totalCount){ q*`
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setPageSize(PAGESIZE); qQG? k~r
setTotalCount(totalCount); ~u2f`67{
setItems(items); n*na6rV\k
setStartIndex(0); w5~j|c=_W
} 6o\uv
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public PaginationSupport(List items, int xP&7i'ag
z},\1^[
totalCount, int startIndex){ 9X;*GC;d
setPageSize(PAGESIZE); udA@9a^;
setTotalCount(totalCount); lN,a+S/'
setItems(items); K/f-9hE F
setStartIndex(startIndex); 5|K[WvG@Co
} "G.X=,
V
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public PaginationSupport(List items, int =RRv&
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totalCount, int pageSize, int startIndex){ Ry]9n.y
setPageSize(pageSize); g0U?`;n$
setTotalCount(totalCount); #G F.M,O/h
setItems(items); 0 D
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setStartIndex(startIndex); _80L/92
} bEQ- ?X%7
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publicList getItems(){ oe
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return items; QkD
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} 0!0e$!8l
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publicvoid setItems(List items){ ,f:K)^yD
this.items = items; !3k-' ),z&
} {4Kvr4)4
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publicint getPageSize(){ 2 (l0Lq*
return pageSize; ?#(LH\$l_
} 8zj&e8&v
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publicvoid setPageSize(int pageSize){ j8[U}~*^
this.pageSize = pageSize; 2-8Dc4H]r
} 0NZ'(qf~9
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publicint getTotalCount(){ \OFmd!Cz
return totalCount; zm5PlG
} ,-E'059
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publicvoid setTotalCount(int totalCount){ }s<;YC
if(totalCount > 0){ ?z l<"u
this.totalCount = totalCount; Z Se30Rl\
int count = totalCount / X 5
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pageSize; #\Rxqh7
if(totalCount % pageSize > 0) SF,:jpt`Z+
count++; b5^>QzgD
indexes = newint[count]; XL.f`N.O
for(int i = 0; i < count; i++){ <iU@ M31
indexes = pageSize * HB5-B XBU
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i; %~Rg`+
} FP=-
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}else{ Er
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this.totalCount = 0; _&V,yp!|
} FVrB#Hw~
} nf"#F@dk
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publicint[] getIndexes(){ uE9,N$\L_
return indexes; 7R:Ij[dV
} a<r,LE
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publicvoid setIndexes(int[] indexes){ {._'Q[
this.indexes = indexes; _%D7D~2r|
} e8xq`:4Y
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publicint getStartIndex(){ ?VE'!DW
return startIndex; l_:P|
} Nr>UZlU8
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publicvoid setStartIndex(int startIndex){ jwE=
if(totalCount <= 0) <Y}m/-sD5
this.startIndex = 0; Q`AlK"G,
elseif(startIndex >= totalCount) 1#_pj
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this.startIndex = indexes 2h51zG#qd
sa o &
[indexes.length - 1]; h>GbJ/^
elseif(startIndex < 0) T{+a48,;
this.startIndex = 0; `+\$
else{ 9Q s5e
this.startIndex = indexes Bx|W#:3e
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[startIndex / pageSize]; O H2IO
} BX[IWP\%
} 1%B9xLq
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publicint getNextIndex(){ #9DJk,SP
int nextIndex = getStartIndex() + hui
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pageSize; 0:[A4S`X
if(nextIndex >= totalCount) L
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return getStartIndex(); #1'q'f:7&
else (b#M4ho*f
return nextIndex; }'x)e
} Z!|r>
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publicint getPreviousIndex(){ HLPRTta.
int previousIndex = getStartIndex() - %pjeA[-m#
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pageSize; #
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if(previousIndex < 0) #`|Nm3b
return0; V9"R8*@-
else ig.Z,R3@r
return previousIndex; v;
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} v\?J=|S+
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} 7MrHu2rZ=
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抽象业务类 4_QfM}Fyp
java代码: t.;._'
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/** oz=ULPZ%
* Created on 2005-7-12 7_s+7x =
*/
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package com.javaeye.common.business; 8TB|Y
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import java.io.Serializable; A8mc+ Bf(
import java.util.List; >>KI_$V
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import org.hibernate.Criteria; xgIb6<qwY
import org.hibernate.HibernateException; aIa<,
import org.hibernate.Session; '12*'Q+{+
import org.hibernate.criterion.DetachedCriteria; RDDA^U7y#
import org.hibernate.criterion.Projections; uNuFD|aQ.
import T=-UcF
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org.springframework.orm.hibernate3.HibernateCallback; \v-I<"::
import [nV BnB
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org.springframework.orm.hibernate3.support.HibernateDaoS 5<PNl~0
Sq,>^|v4&e
upport; #b428-
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import com.javaeye.common.util.PaginationSupport; 4pT^*
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public abstract class AbstractManager extends zC)JOykI%
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HibernateDaoSupport { l([aKm#
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privateboolean cacheQueries = false; %p)&mYK{
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privateString queryCacheRegion; o[Qb/ 7
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publicvoid setCacheQueries(boolean r?[[.zm"7
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cacheQueries){ qQ)1+^
this.cacheQueries = cacheQueries; -|}?+W
} 9rz$c, Y(
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publicvoid setQueryCacheRegion(String LRu*%3xx
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queryCacheRegion){ +zch e
this.queryCacheRegion = %eofG]VM<
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queryCacheRegion; *)w+xWmM3w
} %Jh(5
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publicvoid save(finalObject entity){ 8f~x\.
getHibernateTemplate().save(entity); w`8H=Hf
} ZHZxr
, 2#Q>
publicvoid persist(finalObject entity){ dO z|CfUhI
getHibernateTemplate().save(entity); E]n]_{BN]
} HEFgEYlO
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publicvoid update(finalObject entity){ Ot47.z
getHibernateTemplate().update(entity); lFtEQ '}
} <FBH;}]
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publicvoid delete(finalObject entity){ b1#C,UWK
getHibernateTemplate().delete(entity); rAHP5dx:
} p({@t=L3g
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publicObject load(finalClass entity, Pi5MFw'v
!\{2s!l~
finalSerializable id){ r3' DXP
return getHibernateTemplate().load ?F]P=S:x
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(entity, id); ]s5e[iS
} R2~y<^.V`Y
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publicObject get(finalClass entity, U`3?bhzua
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finalSerializable id){ xa'U_]m
return getHibernateTemplate().get V#$QKn`;
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(entity, id); ,sc#l<v
} xV+\R/)x
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publicList findAll(finalClass entity){ u{=h%d/
return getHibernateTemplate().find("from +Eb-|dM
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" + entity.getName()); )?radg
} 9*FA=E
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publicList findByNamedQuery(finalString JXkx!X_{
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namedQuery){ =/a`X[9vI
return getHibernateTemplate b*S,8vE]
,{:qbt
().findByNamedQuery(namedQuery); eSObOG/
} VFZyWX@#u
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publicList findByNamedQuery(finalString query, S_Nm?;P
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finalObject parameter){ 'q;MhnU+
return getHibernateTemplate X4:84
jbe:"Stw
().findByNamedQuery(query, parameter); JE:LA+ (
} lt4IoE`tk?
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publicList findByNamedQuery(finalString query, [-l>fP0
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finalObject[] parameters){ Ygg+=@].@
return getHibernateTemplate ;8vB7|54.
D+0il=5
().findByNamedQuery(query, parameters); Z)xcxSo
} j8e=],sQ
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publicList find(finalString query){ sV5k@1Y
return getHibernateTemplate().find [V?HK_~
lrHN6:x(Y4
(query); a>4q"IT6
} UK^w;w2F
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publicList find(finalString query, finalObject .yUD\ZGJu
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parameter){ Kk=>"?&
return getHibernateTemplate().find V]Ccj\Oi
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(query, parameter); wsrdBxd5
} 8Wtr,%82
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public PaginationSupport findPageByCriteria R=Lkf
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(final DetachedCriteria detachedCriteria){
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return findPageByCriteria pK{G2]OK{U
Vo{
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); jl7>
} /-lW$.+{?
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public PaginationSupport findPageByCriteria ho^c#>81
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(final DetachedCriteria detachedCriteria, finalint 4?(=?0/[
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startIndex){ A6_ER&9$>N
return findPageByCriteria |I"&Z+m
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(detachedCriteria, PaginationSupport.PAGESIZE, dQH8s
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startIndex); {be|G^.c
} A`vRUl,c=
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public PaginationSupport findPageByCriteria OBlQ
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(final DetachedCriteria detachedCriteria, finalint rFC9y o
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pageSize, \[]BB5)8
finalint startIndex){ jsV1~1:83
return(PaginationSupport) K-*ZS8
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getHibernateTemplate().execute(new HibernateCallback(){ lv.h?"Ml
publicObject doInHibernate 15|gG<-
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(Session session)throws HibernateException { kW%wt1",
Criteria criteria = yoq-H+<
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detachedCriteria.getExecutableCriteria(session); vqUYr
int totalCount = <Cs9$J
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((Integer) criteria.setProjection(Projections.rowCount ):=8w.yC
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()).uniqueResult()).intValue(); &kWT<*;J)
criteria.setProjection M9VAs~&S
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(null); g
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List items = V.Lk70 \
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criteria.setFirstResult(startIndex).setMaxResults I)%bOK]
[ot+EA
(pageSize).list(); -ImO y|
PaginationSupport ps = W>x.*K
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new PaginationSupport(items, totalCount, pageSize, Wa?\W&
)!zg=}V
startIndex); )WEOqaR]
return ps; T9}dgf
} vXdI)Sx[
}, true); A$P Oc<
} a(-t"OL\
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public List findAllByCriteria(final 8-L -W[
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DetachedCriteria detachedCriteria){ "0>AefFd#
return(List) getHibernateTemplate &ML-\aSal
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().execute(new HibernateCallback(){ Aba%QQQ
publicObject doInHibernate L`w_Q2{sv
dt=M#+g
(Session session)throws HibernateException { )ZZ6 (O
Criteria criteria = XaU^^K
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detachedCriteria.getExecutableCriteria(session); _>t6]?*
return criteria.list(); EUPc+D3
} 1NN#-U
}, true); BQgK<_
} c/-'^+9
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public int getCountByCriteria(final 5S! !@P!,
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DetachedCriteria detachedCriteria){ 2tp95E`(O
Integer count = (Integer) >IS BK[=H
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getHibernateTemplate().execute(new HibernateCallback(){ DnB :~&Dw
publicObject doInHibernate c`)[-
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(Session session)throws HibernateException { ph7]*W-
Criteria criteria = U]E~7C
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detachedCriteria.getExecutableCriteria(session); V$MMK
return (=Lx9-u
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criteria.setProjection(Projections.rowCount thh0~g0/
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()).uniqueResult(); )f`oCXh
} Y)C!N$=@Q
}, true); 7Rr
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return count.intValue(); {@X)=.Zf
} w"h3e
} jQ P2[\
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用户在web层构造查询条件detachedCriteria,和可选的 NMH'4R
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 e:;u_be~
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PaginationSupport的实例ps。 \hqjk:o
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ps.getItems()得到已分页好的结果集 /V E|F Ts
ps.getIndexes()得到分页索引的数组 G@6F<L~$1
ps.getTotalCount()得到总结果数 X:OUu;
ps.getStartIndex()当前分页索引 = _/XFN
ps.getNextIndex()下一页索引 bb`8YF+?'
ps.getPreviousIndex()上一页索引 _h P7hhR
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 @@#h-k%k-
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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 \) g?mj^
cFloaCz
一下代码重构了。 9<1dps=c
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我把原本我的做法也提供出来供大家讨论吧: HV8=b"D"
AP/#?
首先,为了实现分页查询,我封装了一个Page类: PI$K+}E
java代码: ~y8KQ-1n"
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/*Created on 2005-4-14*/ Ws:MbZyr
package org.flyware.util.page; 9 wP,Z"
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7z
/** Fz@9
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* @author Joa $3^Cp_p6
* MW|:'D`
*/ D Ax1
publicclass Page { |sPUb;&~
v1\/ dQK
/** imply if the page has previous page */ aJ$({ZN\#
privateboolean hasPrePage; jF0>wm
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/** imply if the page has next page */ e3]v
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privateboolean hasNextPage; #9p|aS\
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/** the number of every page */ rE9Nt9}
privateint everyPage; S0!w]Ku
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/** the total page number */ 4>(rskl_
privateint totalPage; IQQ QB
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/** the number of current page */ O{ |Ug~
privateint currentPage; #=
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/** the begin index of the records by the current L=V.@?
Ex@o&j\93
query */ /J[s5{
privateint beginIndex; QEc4l[^{.B
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/** The default constructor */ 28LYGrB
public Page(){ 1SSS0 &
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} p|Nh:4iN
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/** construct the page by everyPage +PKd
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* @param everyPage "43F.!P
* */ N%!{n7`N:
public Page(int everyPage){ w
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this.everyPage = everyPage; q0VR&b`?>D
} QfRo`l/V9
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/** The whole constructor */ d VyT `
public Page(boolean hasPrePage, boolean hasNextPage, 3U%kf<m=
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int everyPage, int totalPage, cr ~.],$Om
int currentPage, int beginIndex){ U[W &D%'
this.hasPrePage = hasPrePage; qpV"ii
this.hasNextPage = hasNextPage; /n1L},67h
this.everyPage = everyPage; hr3<vWAD
this.totalPage = totalPage; e@7UL|12
this.currentPage = currentPage; du_~P"[
this.beginIndex = beginIndex; N."x@mV
} d8K|uEHVz
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/** ~{-9qOGw;
* @return U;t1 K
* Returns the beginIndex. %BF,;(P
*/ qIvnPaYW
publicint getBeginIndex(){ [G'
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return beginIndex; "w3%BbI x
} ]EqwDw4
ji.T7wn1u
/** 5:(/k\9+yv
* @param beginIndex "<&) G{
* The beginIndex to set. 2=uwGIF
*/ 0G`@^`
publicvoid setBeginIndex(int beginIndex){ /h9v'Y}c
this.beginIndex = beginIndex; m}6Jdt'|
} &pW2R}
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/** 7QRkXs
* @return \&[(PNl
* Returns the currentPage. 5&qBG@Hw]
*/ KkCsQ~po
publicint getCurrentPage(){ wlgR =l
return currentPage; izs=5
} ojc.ykP$
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/** b>Ea_3T/
* @param currentPage OAf}\
* The currentPage to set. [ps4i_
*/ 1)!2D?w
publicvoid setCurrentPage(int currentPage){ q7<=1r+
this.currentPage = currentPage; JJ9R,
8n6
} opTH6a
wV-9T*QrM
/** <!F".9c@A
* @return 8*Ty`G&v
* Returns the everyPage. vIf-TQw
*/ !,]2.:{0z
publicint getEveryPage(){ l+j
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return everyPage; ,0{x-S0jX<
} <<R2
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/** A?ho<@^
* @param everyPage u~PZK.Uf0
* The everyPage to set. KW$.Yy
*/ i|m8#*Hd
publicvoid setEveryPage(int everyPage){ 2#/23(Wc
this.everyPage = everyPage; #x`K4f)
} |AS~sjWSJ
ae" o|Q
/** u U%Z%O
* @return QseV\; z
* Returns the hasNextPage. ZG-#YF.1
*/ GL~
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publicboolean getHasNextPage(){ -fp/3-
return hasNextPage; o`G6!
} -ijzo%&qA
>~_z#2PA
/** `@ny!S|1/
* @param hasNextPage Kg`P@
* The hasNextPage to set. X,bhX/h
*/ Lp/'-Y_
publicvoid setHasNextPage(boolean hasNextPage){ !{ fu(E
this.hasNextPage = hasNextPage; *,t/IA|
} AN3oh1xe:
z?pi/`y8>
/** 8 Vf#t!t
* @return n.t5:SW
* Returns the hasPrePage. ;M~9Yr=1
*/ Y>atJ
publicboolean getHasPrePage(){ <@[;IX`YN
return hasPrePage; @ qi|}($
} )O5@R
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/** \;KSx3o
* @param hasPrePage [ r
* The hasPrePage to set. |P`b"x
*/ }Xfg~%6
publicvoid setHasPrePage(boolean hasPrePage){ ~f"3Wa*\B
this.hasPrePage = hasPrePage; kR3wbA
} {]dG 9
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/** WP?]"H
* @return Returns the totalPage.
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* 2vU-9p {
*/ Pm%5c\ef
publicint getTotalPage(){ D+BiclJ
return totalPage; ?|WoNA~j}`
} 3Gr"YG{,
$-u c#57
/** %|ClYr
* @param totalPage pL!,1D!
* The totalPage to set. 7r^Cs#b+I
*/ (>E/C^Tc%
publicvoid setTotalPage(int totalPage){ #d*0
)w
this.totalPage = totalPage; RyU8{-q
} 5*+DN
U@
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} $gN\%X/n"1
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1zCu1'Wv
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8)>T>-os
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 FPkk\[EU
63J3NwFt
个PageUtil,负责对Page对象进行构造: >F:1a\c
java代码: .c&&@>m@.
V8nQ/9R;
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/*Created on 2005-4-14*/ GyMN;|
package org.flyware.util.page; /W`CqJk-*.
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import org.apache.commons.logging.Log; F(zCvT
import org.apache.commons.logging.LogFactory; ju3@F8AI
;Z`a[\i':
/** jMCd`Q]K
* @author Joa q,<l3r In
* 6rj iZ%
*/ }st~$JsV1
publicclass PageUtil { I\1"E y
he/rt#
privatestaticfinal Log logger = LogFactory.getLog G[]%1
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r]&sXKDc
(PageUtil.class); @*~yVV!5
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/** J[r_ag
* Use the origin page to create a new page X lItg\R
* @param page _>]/. w2=
* @param totalRecords Z.!<YfA)
* @return &bfM`h'
*/ qo7<g*kf~
publicstatic Page createPage(Page page, int Mpyza%zj
!/tV}.*
totalRecords){ }No #_{
return createPage(page.getEveryPage(), R.2i%cU
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page.getCurrentPage(), totalRecords); -?:8sv*X
} GM9[ 0+u;
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/** \m}a%/
* the basic page utils not including exception <}A6 )=T
f*rub. y
handler DJ7ak>"R
* @param everyPage jtpHDS
* @param currentPage llR5qq=t
* @param totalRecords )m3emMO2
* @return page Q:7P
/
*/ <*z'sUh+}
publicstatic Page createPage(int everyPage, int T^v o9~N*
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currentPage, int totalRecords){ F.x7/;
everyPage = getEveryPage(everyPage); Rf8ZH
currentPage = getCurrentPage(currentPage); VyNF)$'T
int beginIndex = getBeginIndex(everyPage, }Hg\
tj}i
f/Y7@y
currentPage); "PElQBLP:
int totalPage = getTotalPage(everyPage, 0sKoNzE
x1`(Z|RJ
totalRecords); o6|-
:u5_/
boolean hasNextPage = hasNextPage(currentPage, lH`c&LL-=!
"Dk@-Ac
totalPage); ^Ss<<
boolean hasPrePage = hasPrePage(currentPage); yK"\~t[@X:
Qi dI
returnnew Page(hasPrePage, hasNextPage, w5s&Ws
everyPage, totalPage, 5wh(Qdib
currentPage, yx&}bu\
87 B$
beginIndex); .@+M6K*
} e 2NF.
/6[vF)&
privatestaticint getEveryPage(int everyPage){ ]AM*9!
return everyPage == 0 ? 10 : everyPage; ws,?ImA
} roAHkI
2B6u)
95
privatestaticint getCurrentPage(int currentPage){ *^7^g!=z2
return currentPage == 0 ? 1 : currentPage; g#l!b%$
} 35AH|U7b
tC$+;_=+F
privatestaticint getBeginIndex(int everyPage, int j|o/>^ 'e
{wt9/IlG1
currentPage){ Gdx%#@/
return(currentPage - 1) * everyPage;
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} z;@<J8I
c[X6!_
privatestaticint getTotalPage(int everyPage, int G.iQ\'1_h
MFO%F) 5
totalRecords){ 5>CeFy
int totalPage = 0; ,K6ODtw.
k5bv57@
if(totalRecords % everyPage == 0) WdC7CK
totalPage = totalRecords / everyPage; rk&oKd_&i
else pX>wMc+
totalPage = totalRecords / everyPage + 1 ; Ekrpg^3qp"
W^ask[46R
return totalPage; knHrMD;
} XAF]B,h=
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privatestaticboolean hasPrePage(int currentPage){ [a$1{[|)
return currentPage == 1 ? false : true; ]5`A8-Q@
} uQW[2f
x~8R.Sg
privatestaticboolean hasNextPage(int currentPage, <?8cVLW}O
d/3&3>/
int totalPage){ {[NQD3=+F
return currentPage == totalPage || totalPage == 1y U!rEH
OEbZs-:
0 ? false : true; tVX|e2Y
} !f/^1k}SR
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} Gb Mu;CA
2y8FP#
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Ly, ];
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上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 r[kHVT8
!{uV-c-5,
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 F3Vvqt*2
{BA Z`I
做法如下: Of-gG~
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 C`3fM05g
^( C,LVP<
的信息,和一个结果集List: EOqV5$+
java代码: sZqi)lo-s
G~*R6x2g
YWi Y[
/*Created on 2005-6-13*/ CSm(yB{|pC
package com.adt.bo; ahM?;p
c-@EHv
import java.util.List; pAN$c"
I]m&h!
import org.flyware.util.page.Page; /dX,]OFm
.&^M
Z8
/** FuBUg _h
* @author Joa m]=G73jzO
*/ .:;q8FL/
publicclass Result { T[0CD'|E
"6?Y$y/wm
private Page page; rHjR 4q
T z+Y_
private List content; MI8c>5?
E*9W'e~=
/** W`wT0kP?*]
* The default constructor `wLmGv+V
*/ 2V+[:>F
public Result(){ g@>y`AFnr
super(); %-!:$ 1;
} ;]/cCi
JvW!w)$pY
/** ,Qe`(vU*s
* The constructor using fields :KRe==/
* 63i&e/pv
* @param page 9B3}LVg\
* @param content .N#grk)C
*/ zq#gf
public Result(Page page, List content){ ooYs0/,{
this.page = page; zfml^N
this.content = content; ?nR$>a`
} }T=\hM
,}Ic($To
/** AlgVsE%Va
* @return Returns the content. VD=F{|^
*/ n6IN I~,
publicList getContent(){ h&{>4{
return content; o`ODz[04
}
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y=}a55:qE
/** mO\=#Q>
* @return Returns the page. a>nV!b\n5
*/ 9>5]y}.{
public Page getPage(){ e=Kr>~q=
return page; cXOb=
} )jRaQ~Sm
q]*:RI?wGT
/** f6HDfJmE
* @param content Z:MU5(Te
* The content to set. =(5}0}j
*/ `&/ zOMp
public void setContent(List content){ P$;_YLr
this.content = content; vnz}Pr! c
} jCt[I5"+z
&4L+[M{J@4
/** oX1{~lDJl
* @param page :3*0o3C/
* The page to set. Bk1gE((
*/ %5bN@XD
publicvoid setPage(Page page){ HmEU;UbO-
this.page = page; |<7nf7 5c}
} s|8_R;
} x "PMi[4
N
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((_v>{
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2. 编写业务逻辑接口,并实现它(UserManager, r+Y]S-o:
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UserManagerImpl) !O8vr4=
java代码: L_7-y92<W
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nF|m*_DW
/*Created on 2005-7-15*/ <0)@Ikhx
package com.adt.service; uI[lrMQYa
IqONDdep9
import net.sf.hibernate.HibernateException; P!2[#TL0
,t>/_pI+=
import org.flyware.util.page.Page; @AkD-}^[
[PW*|U
import com.adt.bo.Result; )c<5:c
"7a;Apq*
/** rB%acTCz=[
* @author Joa Q1@V?`rkS{
*/ #9Dixsl*Q
publicinterface UserManager { }u..m$h
3&JsYQu
public Result listUser(Page page)throws K29KS)~;W
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HibernateException; c=HL
6v<
f_Q_qckB%x
} WAcQRa~C
2myHn/%C
F D6>[W
r&ex<(I{
"%Eyb\V!
java代码: /ZKO\q
~A=Z/46*Z
;HaG-c</
/*Created on 2005-7-15*/ 4E& 3{hnp
package com.adt.service.impl; PDssEb7
H\<C@OkJS}
import java.util.List; nZM|8
yf7p0;$?
import net.sf.hibernate.HibernateException; 7nHlDPps)
"V cG3.
import org.flyware.util.page.Page; t1
.6+
import org.flyware.util.page.PageUtil; wBXgzd%L
KArnNmJ9
import com.adt.bo.Result; eESJk14
import com.adt.dao.UserDAO; -3c?Yaf"
import com.adt.exception.ObjectNotFoundException; 5fBW#6N/
import com.adt.service.UserManager; hU `H\LE
cS ;hyLd
/** 9Kyr/6w4-k
* @author Joa Re
b^w,
*/ Y&5h_3K;<
publicclass UserManagerImpl implements UserManager { 8a1G0HRQ
a8%/Xwr~
private UserDAO userDAO; '?k*wEu
B9^@]
/** Jj'~\j
* @param userDAO The userDAO to set. w_I}FPT<(:
*/ Aj4i}pT
publicvoid setUserDAO(UserDAO userDAO){ &`63"^y
this.userDAO = userDAO; {E`f(9r:
} A:ef}OCL
i5*sG^<$H
/* (non-Javadoc) @hWt.qO3s
* @see com.adt.service.UserManager#listUser {j
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(org.flyware.util.page.Page) R
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*/ E7axINca
public Result listUser(Page page)throws ]baO{pJi
u<\/T&S
HibernateException, ObjectNotFoundException { #x&1kHu<
int totalRecords = userDAO.getUserCount(); F
3}cVO2bY
if(totalRecords == 0) P{)eZINlE
throw new ObjectNotFoundException :nw4K(:f
avk0pY(n
("userNotExist"); [N925?--S
page = PageUtil.createPage(page, totalRecords); -q\1Tlc]3
List users = userDAO.getUserByPage(page); t1.5hsp
returnnew Result(page, users); O- &>Dc
} pXCmyLQ
8fJ- XFK$:
} 0*8[m+j1
y:Qo:Z~
(3"V5r`*;
Ut8yA"Y~
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CM
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 }dE0WJcO
FbHk6(/)
询,接下来编写UserDAO的代码:
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3. UserDAO 和 UserDAOImpl: R b 6`k^
java代码: 0AFjO)
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/*Created on 2005-7-15*/ j#0@%d
package com.adt.dao; A3 bE3Fk$
throws HibernateException; .T/\5_Bx
vVmoV0kGt
publicList getUserByPage(Page page)throws =zt@*o{F
)avli@W-3j
HibernateException; InMF$pw
+hRAU@RA
} *obBo6!zM
gyJ$Jp
<MI>>$seiJ
\L(~50{(
pog*}@OS
java代码: KE`}P<K&
]4yWcnf
B{lBUv(B
/*Created on 2005-7-15*/ V,fSn:8%M
package com.adt.dao.impl; egxh
sME3s-
import java.util.List; )}1J.>5
r%JJ5Al.S
import org.flyware.util.page.Page; hdp;/Qz&
S.aSNH<
import net.sf.hibernate.HibernateException; 3@*J=LGhKc
import net.sf.hibernate.Query; Oj6 -
YgCJ s;
import com.adt.dao.UserDAO; 0$%:zHi5g
dQQh$*IL?{
/** (2Z-NVU#
* @author Joa V lXUrJ9&
*/ fa;\4#
public class UserDAOImpl extends BaseDAOHibernateImpl t{|
KL<d]
PW x9CT
implements UserDAO { +;tXk
U@!e&QPn
/* (non-Javadoc) +LCpE$H
* @see com.adt.dao.UserDAO#getUserByName nc!P
!M
Wqy|Y*$qT
(java.lang.String) L]3 V)`}
*/ >fJY
publicList getUserByName(String name)throws u;GS[E4
i<l_z&
HibernateException { K2<"O qp_W
String querySentence = "FROM user in class 7,ysixY
9^,MC&eb
com.adt.po.User WHERE user.name=:name"; V)72]p
Query query = getSession().createQuery '.r_6X$7Jt
<spV Up
(querySentence); A'HFpsa
query.setParameter("name", name); L}pMjyM
return query.list(); K>hQls+
} //n$#c_}u
{b6| wQ\
/* (non-Javadoc) s4/4o_[W
* @see com.adt.dao.UserDAO#getUserCount() kHygif
!I4
*/ :3J,t//c
publicint getUserCount()throws HibernateException { 9&}$C]`
int count = 0; U,Ya^2h%
String querySentence = "SELECT count(*) FROM (pN:ET B
O%L]*vIr
user in class com.adt.po.User"; VAX@'iZr
Query query = getSession().createQuery mN?y\GB
N"1o>
!
(querySentence); d(9ZopJrQ
count = ((Integer)query.iterate().next @k['c
SEa'>UG
()).intValue(); ZxLd h8v.
return count; (3~h)vaJ
} jR[VPm=
lZ|+.T!g?
/* (non-Javadoc) ]Jz2[F"J
* @see com.adt.dao.UserDAO#getUserByPage S-l<+O1fy
q#B=PZ'NA
(org.flyware.util.page.Page) Ut.%=o;&[
*/ m/@ ;N,K
publicList getUserByPage(Page page)throws !Hq$7j_
2o2jDQ|7
HibernateException { @6\Id7`Ea
String querySentence = "FROM user in class DSjEoWj
X5@+M!`
com.adt.po.User";
|Hx#Uk#
Query query = getSession().createQuery SO @d\H
n@|5PI"bx
(querySentence); 5My4a9
query.setFirstResult(page.getBeginIndex()) Od_xH
.setMaxResults(page.getEveryPage()); Iv])s
return query.list(); }7?_>
} 6G.(o
C.qNBl*
} 'D_a2xo0
=rz7 x
:%G_<VAo!
o;#:%
lTb4quf8I
至此,一个完整的分页程序完成。前台的只需要调用 b9nTg
1eHU!{<fqm
userManager.listUser(page)即可得到一个Page对象和结果集对象 Zp8\n:
o%3i(H
的综合体,而传入的参数page对象则可以由前台传入,如果用 >7g #e,d
'Ur1I"
webwork,甚至可以直接在配置文件中指定。 [$\KS_,Mn
B&