Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 763v
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 +eFFSt
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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 -Xxqm%([71
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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 n#wI@W>%+
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。 Db;G@#x
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分页支持类: Y6Lf@}2(i
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java代码: mo[Zb0>
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package com.javaeye.common.util; ~:3QBMk::
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import java.util.List; 34d3g
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publicclass PaginationSupport { V{^!BBQ
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publicfinalstaticint PAGESIZE = 30; 89wU-Aggq
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privateint pageSize = PAGESIZE; Fl1;;F
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privateList items; &<UMBAS
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privateint totalCount; TJ1+g
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privateint[] indexes = newint[0]; p TeOW9
@ ]/AjjLt
privateint startIndex = 0; s;64N'HH
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public PaginationSupport(List items, int DM}YJ
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totalCount){ []A%<EI7
setPageSize(PAGESIZE); sfOHarww
setTotalCount(totalCount); jSwf*u
setItems(items); T`Mf]s)*
setStartIndex(0); CC@.MA@9N
} SL;9Q[
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public PaginationSupport(List items, int 3Ei5pX =g
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totalCount, int startIndex){ I;Bjfv5
setPageSize(PAGESIZE); yRiP{$E
setTotalCount(totalCount); QC X8IIHG
setItems(items); E5N{j4\F
setStartIndex(startIndex); $pFo Rv
} ;Hj~n+
*
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public PaginationSupport(List items, int sH?/E6
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totalCount, int pageSize, int startIndex){ V`7FKL@"
setPageSize(pageSize); ^pe{b9c
setTotalCount(totalCount); +{L<? "
setItems(items); YBP:q2H
setStartIndex(startIndex); K!] 1oy'V
} M>>qn_yq4
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publicList getItems(){ 8WXJ.
return items; Jte#ZnP
} vMs$ceq
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publicvoid setItems(List items){ E4W zU
this.items = items; }-o{ASC#
} y:h}z).
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publicint getPageSize(){ ;x8k[p~2
return pageSize; Wxbq)Z[V
} OLvcivf
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publicvoid setPageSize(int pageSize){ ]Wq?H-B{
this.pageSize = pageSize; \;mH(-
} rJ!{/3e
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publicint getTotalCount(){ 1[t=XDz/e
return totalCount; U=o"32n+
} ^=^z1M2P
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publicvoid setTotalCount(int totalCount){ {s_+?<l
if(totalCount > 0){ Gsc\/4Wx
this.totalCount = totalCount; Z+StB15
int count = totalCount / zWb4([P;
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pageSize; XFh>U7z.
if(totalCount % pageSize > 0) yGsz2T;w
count++; lZrVY+D
indexes = newint[count]; )5.C]4jol
for(int i = 0; i < count; i++){ v,\R,{0
indexes = pageSize * M!tXN&V]
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i; -Z?Vd!H:
} (} 5S
}else{ /De^
this.totalCount = 0; }h}<!s
} mnID3=JF
} *\o/q[
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publicint[] getIndexes(){ .<K
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return indexes; wHem5E
} /^ " 83?_
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publicvoid setIndexes(int[] indexes){ Bs MuQ|!
this.indexes = indexes; Go&D[#
} 033T>qY
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publicint getStartIndex(){ kGUJ9Du
return startIndex; 07/L}b`P
} (?*BB3b`
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publicvoid setStartIndex(int startIndex){ 0'r%,0
if(totalCount <= 0) D)brPMS:o
this.startIndex = 0; _7D _72
elseif(startIndex >= totalCount) zj|/ CxV
this.startIndex = indexes "aF8l<1xn
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[indexes.length - 1]; pfd#N[c
elseif(startIndex < 0) NA.1QQ;e
this.startIndex = 0; e\b`n}nC
else{ lZQ/W:OE
this.startIndex = indexes c:l]=O
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[startIndex / pageSize]; Q#Y k?Kv~
} a?R[J==
} @wq#>bm
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publicint getNextIndex(){ IF@HzT;Q
int nextIndex = getStartIndex() + IOK}+C0e
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pageSize; @:x"]!1
if(nextIndex >= totalCount) "*7C`y5&P
return getStartIndex(); L"<B;u5pM
else LihjGkj\g
return nextIndex; #~Q8M*~@
} 9B+wYJp
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publicint getPreviousIndex(){ d/7l efF
int previousIndex = getStartIndex() - QT#6'>&7-b
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pageSize; Q&M'=+T
if(previousIndex < 0) 2*U.^]~"{
return0; d \>2
else >m_v5K
return previousIndex; %McO6.M@
} 2@vj!U 8
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} v.W{x?5
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抽象业务类 oJ78jGTnb
java代码: :k46S<RE
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/** CsS p=(
* Created on 2005-7-12 -cNx1et
*/ v@G4G*x\
package com.javaeye.common.business; |
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import java.io.Serializable; ~_ !ts{[E
import java.util.List; Xz;b,C&*t
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import org.hibernate.Criteria; C4$/?,K(
import org.hibernate.HibernateException; ]2+g&ox4'
import org.hibernate.Session; fo\\o4Qyh
import org.hibernate.criterion.DetachedCriteria; r3I,11B
import org.hibernate.criterion.Projections; 4Y
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import !W1eUY
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org.springframework.orm.hibernate3.HibernateCallback; {TZE/A3D,
import N_C_O$j
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org.springframework.orm.hibernate3.support.HibernateDaoS H?}wl%
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upport; um8AdiK
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import com.javaeye.common.util.PaginationSupport;
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@~jxG%y86
public abstract class AbstractManager extends zj]b&In6;
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HibernateDaoSupport { # bX~=`
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privateboolean cacheQueries = false; Sb^
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privateString queryCacheRegion; |#TXE|#ux
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publicvoid setCacheQueries(boolean +0pW/4x
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cacheQueries){ i+~QDo(Pi
this.cacheQueries = cacheQueries; Rlw9$/D!Z
} PO
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publicvoid setQueryCacheRegion(String ;]&-MFv#
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queryCacheRegion){ bNvAyKc-
this.queryCacheRegion = ?^3B3qqh9
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queryCacheRegion; R}J-nJlb
} ' yNPhI
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publicvoid save(finalObject entity){ .]Ybp2`"U
getHibernateTemplate().save(entity); v#=ayWgk
} n0.8)=;2
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publicvoid persist(finalObject entity){ ",Wf uz
getHibernateTemplate().save(entity); Pi%tsKk%
} \o9@[t>&2
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publicvoid update(finalObject entity){ $T*KaX\{B
getHibernateTemplate().update(entity); E:Y:X~vy
} y<r44a_!
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publicvoid delete(finalObject entity){ q[boWW
getHibernateTemplate().delete(entity); < EXWWrm
} ",ad7Y7i
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publicObject load(finalClass entity, }'jV/
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finalSerializable id){ Ck(.N
return getHibernateTemplate().load nx :)k-p_[
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(entity, id); ^"`Z1)V
} \|!gPc%s
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publicObject get(finalClass entity, &5/JfNe3
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finalSerializable id){ {gIEZ{
return getHibernateTemplate().get [i9[Mj
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(entity, id); 9&(.x8d,a
} 3^H/LWx`{]
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publicList findAll(finalClass entity){ aa=b<Cd
return getHibernateTemplate().find("from !@yQK<0
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" + entity.getName()); IuWX*b`v
} ~mcZUiP9
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publicList findByNamedQuery(finalString o@@w^##
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namedQuery){ F=5kF/}x-z
return getHibernateTemplate Ko-QR(
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().findByNamedQuery(namedQuery); q5gP~*?
} coO.kTO;
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publicList findByNamedQuery(finalString query, #x|VfN5f
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finalObject parameter){ MZiF];OY
return getHibernateTemplate |bvGYsn_#=
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().findByNamedQuery(query, parameter); Ris-tdg
} eb7UoZw
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publicList findByNamedQuery(finalString query, /]l f>\x1
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finalObject[] parameters){ Q5T(nEA
return getHibernateTemplate :9O|l)N)W=
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().findByNamedQuery(query, parameters); SJF 2k[da
} ~:s!].H
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publicList find(finalString query){ v5gQ9
return getHibernateTemplate().find %SFw~%@3&~
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(query); e7wKjt2fy
} 6z`8cI+LRw
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publicList find(finalString query, finalObject
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parameter){ 3_@G{O)e
return getHibernateTemplate().find .1%i`+uZ
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(query, parameter); I$F\(]"@
} (F_7%!g1d
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public PaginationSupport findPageByCriteria I>8Bc
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(final DetachedCriteria detachedCriteria){ "9.6\Y\*
return findPageByCriteria ~v,!n/('
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); Zm5nLxM
} ]#+5)[N$>
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public PaginationSupport findPageByCriteria q
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(final DetachedCriteria detachedCriteria, finalint @D2`*C9
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startIndex){ 5@""_n&FV
return findPageByCriteria yW'BrTw
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(detachedCriteria, PaginationSupport.PAGESIZE, N_|YOw6
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startIndex); @$_rEdwi
} PwRNBb}6
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public PaginationSupport findPageByCriteria x%ZiE5#
pvI&-D #}
(final DetachedCriteria detachedCriteria, finalint '$lw[1
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pageSize, 7=AO^:=bx
finalint startIndex){ C[^a/P`i
return(PaginationSupport) ?T~3B]R
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getHibernateTemplate().execute(new HibernateCallback(){ 30e(4@!4vW
publicObject doInHibernate vBV"i9n
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(Session session)throws HibernateException { -_:JQ
Criteria criteria = (d1V1t2r6
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detachedCriteria.getExecutableCriteria(session); oM m/!Dc
int totalCount = ZD
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}P7xdQ6
((Integer) criteria.setProjection(Projections.rowCount +*]SP@|IYI
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()).uniqueResult()).intValue(); bkJn}Al;
criteria.setProjection =r=^bNO
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(null); #IcT
@(
List items = s#4))yUR6Z
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criteria.setFirstResult(startIndex).setMaxResults _AA`R`p;
bi,rMgW
(pageSize).list(); c'>8pd
PaginationSupport ps = 0^_)OsFA
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new PaginationSupport(items, totalCount, pageSize, C _k_D
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startIndex); -uS7~Ww.a
return ps; e{d_p%(
} 'bd=,QW
}, true); 7~QwlU3n<F
} zcbA)
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public List findAllByCriteria(final jFK9?cLT
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DetachedCriteria detachedCriteria){ xQcMQ{&;
return(List) getHibernateTemplate b3jU~L$
}6b7a1p
().execute(new HibernateCallback(){ 5[0l08'D
publicObject doInHibernate `3H?*\<(
*&~sr
(Session session)throws HibernateException { Bil;@,Z#
Criteria criteria = M]pel\{M
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detachedCriteria.getExecutableCriteria(session); `RL(N4H
return criteria.list(); _r^G%Mvy|
} ]ys4
}, true); RJ7/I/yD|
} rmAP&Gw I
,L8I7O}A;
public int getCountByCriteria(final cftn`:(&8
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DetachedCriteria detachedCriteria){ mDe+ M{/
Integer count = (Integer) Ynt&cdK9
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getHibernateTemplate().execute(new HibernateCallback(){ 5Od(J5`
publicObject doInHibernate '8((;N|I^
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(Session session)throws HibernateException { 8*Nt&`@
Criteria criteria = gs<qi'B
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detachedCriteria.getExecutableCriteria(session); jn#N7%{Mk
return G> 5=`
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criteria.setProjection(Projections.rowCount '+GVozc6c"
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()).uniqueResult(); HtS1N}@
} rVIb'sa
}, true); /s-jR]#VA
return count.intValue(); 5O4&BxQ~}
} q#':aXcv"
} LU 5
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用户在web层构造查询条件detachedCriteria,和可选的 WhVmycdv
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 S'H0nJ3
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PaginationSupport的实例ps。 _|Kv~\G!
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ps.getItems()得到已分页好的结果集 |]
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ps.getIndexes()得到分页索引的数组 JJZXSBAOU
ps.getTotalCount()得到总结果数 9lazo
ps.getStartIndex()当前分页索引 3K;b~xg`nw
ps.getNextIndex()下一页索引 ]!S)O|_D[
ps.getPreviousIndex()上一页索引 emDvy2uA#
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 b~jvmcr
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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 "Jv,QTIcS
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一下代码重构了。 IUBps0.T\
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我把原本我的做法也提供出来供大家讨论吧: ~IN$hKg^
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首先,为了实现分页查询,我封装了一个Page类: 7{/:,
java代码: "1j\ZCXK_Z
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/*Created on 2005-4-14*/ p2_Zsq
package org.flyware.util.page; aPP<W|Cmo2
cX]{RVZo-/
/** F~- S3p
* @author Joa 0 VgnN
* QCY{D@7T
*/ TH}ycue
publicclass Page { 'C?f"P:X{
6+d"3-R.
/** imply if the page has previous page */ mUY:S
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privateboolean hasPrePage; ,Vn]Ft?n
{<{G 1y~
/** imply if the page has next page */ J'4@-IM
privateboolean hasNextPage; YQ`#C#Wb
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/** the number of every page */ hF PRC0ftE
privateint everyPage; h.+&=s!Nsy
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/** the total page number */ gB{R6
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privateint totalPage; T_B.p*\BM
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/** the number of current page */ gkn/E}K#
privateint currentPage; bb_jD^
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/** the begin index of the records by the current t>`LO
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query */ hADb]O
privateint beginIndex; w`!foPE
w 4gZ:fR=
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/** The default constructor */ nv[Sb%/
public Page(){ ,* vnt6C*
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} Q7aDl8L xn
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/** construct the page by everyPage Ip|^?uyrk
* @param everyPage vo<#sa^,j
* */ 8BH)jna`Qo
public Page(int everyPage){ Leick6
this.everyPage = everyPage; Wn#JYp
} C>;8`6_!gU
p. ~jo
/** The whole constructor */ #i=^WN<V
public Page(boolean hasPrePage, boolean hasNextPage, $I]x &cF
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bh"v{V`=0
int everyPage, int totalPage, D&d:>.~u
int currentPage, int beginIndex){ 67:<X(u+!
this.hasPrePage = hasPrePage; !Jp.3,\?~
this.hasNextPage = hasNextPage; #UN{
J6{
this.everyPage = everyPage; 2EcYO$R!
this.totalPage = totalPage; +VCo=oA
this.currentPage = currentPage; D>^ix[:J
this.beginIndex = beginIndex; Sqt"G6<
} 3E@&wpj
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/** <%f%e4
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* @return EUS]Se2
* Returns the beginIndex. Y9ce"*b
*/ <RsKV$Je
I
publicint getBeginIndex(){ Kd1\D!#!6
return beginIndex; %,q#f#
} Cx'=2Y 7
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/** H)fo4N4ii
* @param beginIndex fy4JW,c
* The beginIndex to set. bUB6B
*/ rAdcMFW
publicvoid setBeginIndex(int beginIndex){ 7B2Og{P
this.beginIndex = beginIndex; iDxgAV f*
} .7rsbZzs
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/** 3AL=*qq
* @return Q>*K/%KD
* Returns the currentPage. 1T?%i
*/ Wf w9cxGkf
publicint getCurrentPage(){ }X:r:{r
return currentPage; phSP+/w
} _)"
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/** 3yX^R^`
* @param currentPage <Y6>L};
* The currentPage to set. \Rt
*/ 41D[[Gh
publicvoid setCurrentPage(int currentPage){ nu-wQr
this.currentPage = currentPage; HJrg
} Om{ML,d
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/** $&C%C\(>D
* @return @V u[Tg}J
* Returns the everyPage. JPzPL\
*/ x;aZ&
publicint getEveryPage(){ e]fC!>w(\
return everyPage; 1'B?f# s
} 4"=pcHNV
(o=iX,@'2
/** Q{kuB+s
* @param everyPage Y[,C1,
* The everyPage to set. *~X\c Z
*/ Ms3/P| {"p
publicvoid setEveryPage(int everyPage){ 4B
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this.everyPage = everyPage; 6>%NL"* ]
} .{>-.&
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/** @gk[sQ\O
* @return K)Ka"H
* Returns the hasNextPage. %LmB`DqZ
*/ AkC\CdmA
publicboolean getHasNextPage(){
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return hasNextPage; }]@
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} 2O>iAzc
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/** d|lzkY~
* @param hasNextPage ?-i&6 i6Y
* The hasNextPage to set. pqX=l%{4ES
*/ kXRD_B5&
publicvoid setHasNextPage(boolean hasNextPage){ *i90[3l
this.hasNextPage = hasNextPage; JH9CN
} )63w&
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/** v\u+=}rl
* @return 07&S^ X^/
* Returns the hasPrePage. Pr'py
*/ 35et+9
publicboolean getHasPrePage(){ C%h_!z":
return hasPrePage; _uacpN/<|
} @ZZ Lh=
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/** p};<l@
* @param hasPrePage W'yICt(#G
* The hasPrePage to set. Fx 2&ji6u
*/ 3f
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publicvoid setHasPrePage(boolean hasPrePage){ 6A<aelE*i
this.hasPrePage = hasPrePage; ~C3-E %h@Z
} K[Kc'6G
7EUaf;d^
/**
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* @return Returns the totalPage. $TiAJ}:
* ,P]{*uqGiB
*/ u)ItML
publicint getTotalPage(){ 57rP@,vj
return totalPage; Pc-HQU
} C_o.d~xm
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/** {Gy_QRsp,
* @param totalPage 1l{n`gR
* The totalPage to set. + `xp+Q
*/ DzMk eX
publicvoid setTotalPage(int totalPage){ Zf! 7pM
this.totalPage = totalPage; H>?@nYP
} 5sRNqTIr
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}
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上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 1k`!w}
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个PageUtil,负责对Page对象进行构造: '=5N?)
java代码: wlJ_,wA
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/*Created on 2005-4-14*/ wP'`!O[W
package org.flyware.util.page; `*B8IT)
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import org.apache.commons.logging.Log; ! JN@4
import org.apache.commons.logging.LogFactory; XT\;2etVL
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/** #&^+hx|
* @author Joa qH$p]+Rk 5
* 1Pbp=R/7ar
*/ .(krB%N
publicclass PageUtil { U]d+iz??b
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privatestaticfinal Log logger = LogFactory.getLog G{<wXxq%
E[y?\{
(PageUtil.class); ["z$rk
afjC~}
/** R_ csKj
* Use the origin page to create a new page 4)?c[aC4P
* @param page 'W)x<Iey1
* @param totalRecords %rYt; 7B
* @return Mg].#
*/ iV%%VR8b
publicstatic Page createPage(Page page, int g`6S*&8I
Gl+}]Vn[n
totalRecords){ Eyuc~[
return createPage(page.getEveryPage(), ,QDq+93
}-!$KR]:s
page.getCurrentPage(), totalRecords); NEvt71k
} i
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/** qsLsyi |zG
* the basic page utils not including exception rq=R},p
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handler BJvVZl2h
* @param everyPage UV=TU=A\o
* @param currentPage 7Sokn?~i
* @param totalRecords ~V<jeb
* @return page ;^;5"nh
*/ Zhw _L
publicstatic Page createPage(int everyPage, int d(&vIjy
T]+*}C
currentPage, int totalRecords){ 6;VlX,,j
everyPage = getEveryPage(everyPage); <1ai0]
currentPage = getCurrentPage(currentPage); YO=;)RA
int beginIndex = getBeginIndex(everyPage, `ul"D%
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currentPage); r`lgK2r\
int totalPage = getTotalPage(everyPage, bf3)^ 49}
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totalRecords); 8s|r'
boolean hasNextPage = hasNextPage(currentPage, !0cfz5t
y};qo'dlt
totalPage); 9"/{gf3D
boolean hasPrePage = hasPrePage(currentPage); 0DN:{dJz
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returnnew Page(hasPrePage, hasNextPage, mv5!fp_*7
everyPage, totalPage, -i9/1.Z
currentPage, %e_WO,R
,u$$w
beginIndex); ,2u]rLxx;
} ow+NT
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privatestaticint getEveryPage(int everyPage){ lVMAab
return everyPage == 0 ? 10 : everyPage; lG q;kIQ
} 7/Ew(X8Fs
guBOR0x`
privatestaticint getCurrentPage(int currentPage){ vhT9#) HI
return currentPage == 0 ? 1 : currentPage; >5 Ce/P'R
} NAL%qQ
ZWYwVAo
privatestaticint getBeginIndex(int everyPage, int 9;.dNdg>
hd+JKh!u
currentPage){ gJ2R(YMF
return(currentPage - 1) * everyPage; 1298&C@
} _QCAV+K'
i;yz%Ug
privatestaticint getTotalPage(int everyPage, int -^C;WFh8)
#[J..i/h
totalRecords){ bvZmozbD
int totalPage = 0; }Dk_gom_
Jg^tr>I~
if(totalRecords % everyPage == 0) SxMh '
totalPage = totalRecords / everyPage; I#9A\.pO
else UT"L5{c
totalPage = totalRecords / everyPage + 1 ; A9F Z`
@"Do8p!*(6
return totalPage; )TG\P,H9
} P%.9 g
z.#gpTXD
privatestaticboolean hasPrePage(int currentPage){ D4_D{\xhO
return currentPage == 1 ? false : true; +BmA4/P$
} df}B:?Ew.
fyT! /
privatestaticboolean hasNextPage(int currentPage, IiSO{
3vDV
int totalPage){ ;9d(GP}eE
return currentPage == totalPage || totalPage == i9w xP i
7M5HIK6_
0 ? false : true; T7&itgEYG/
} <4^a(Zh
@ -g^R4e<
*j8w"
4
} &:w{[H$-
:'#BU:
hnL(~
%kKtPrT
jUdW o}/
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。 &9IMZAo
BYP,}yzA
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 !dGy"-i$h
1 BVivEG
做法如下: UIbVtJ
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 (Z
sdj
l0Y(9(M@
的信息,和一个结果集List: foaNB=,
java代码: (iH5F9WO
$O7>E!uVD
(]'4_~e
/*Created on 2005-6-13*/ O]i}r`E8,
package com.adt.bo; %5jxq9:K
Ci=c"JdB
import java.util.List; /\h&t6B1
DS-Kot(k(z
import org.flyware.util.page.Page; <"aPoGda
e$ E=n
/** [G4#DP\t>p
* @author Joa XA>@0E>1r
*/ t~gnai
publicclass Result { qky{]qNW
UP%X`
private Page page; *(s)CWf
Wv$e/N`l
private List content; Aln\:1MU
:8MpSvCV
/** sm/l'e
* The default constructor Uo5l
=\
*/ @I#@%"AW
public Result(){ hZ5h(CQ?"#
super(); X|@|ZRN
} qzsS"=5
(Kv[~W7lb
/** Jc:*X4-'
* The constructor using fields tb^3-ZUb
* A1>R8Zuhy
* @param page #Z(8 vA^@
* @param content 67')nEQ9
*/ r4D6g>)h1q
public Result(Page page, List content){ Z_cTuu0'
this.page = page; }=az6cLE2
this.content = content; 5}E8Tl
} UACWs3`s+
?UQE;0 B
/** ?:~Y%4;
* @return Returns the content. 2Cj?k.Zk
*/ +Q8Bin
publicList getContent(){ zf4@:GM`
return content; 83Bp_K2\
} +wgNuj0=*
}I9\=jT
/** y!)Z ^u
* @return Returns the page. 5! NK
*/ jun>(7
public Page getPage(){ r,EIOcz:
return page; 4JT9EKo
} *3s4JK
wBA[L}
/** W,}HQ
* @param content 3;>|*(cO
* The content to set. y8D'V)B
*/ e{>X2UNW
public void setContent(List content){ k]] (I<2
this.content = content; Yvcd(2
} Ir_K83VM
+q|2j>k@
/** bYYyXM
* @param page ez"Xb 7
* The page to set. ?A3pXa
*/ 3BDAvdJ4.
publicvoid setPage(Page page){ \8'fy\
this.page = page; p%jl-CC1
} W8'cAY
} %J!+f-:=
SYOND>E
5P,{h
zC\ pd#
\`-/\N
2. 编写业务逻辑接口,并实现它(UserManager, 7q<I7Wt
N X4!G>v
UserManagerImpl) !=;^Grv>
java代码: >%h_ R:
!?`5r)K
G9TK)Nz
/*Created on 2005-7-15*/ >?ZH[A
package com.adt.service; k-@CcrepF
iov55jT~l@
import net.sf.hibernate.HibernateException; c{Nk"gEfRA
)q&=x2`
import org.flyware.util.page.Page; +/*g?Vt
?%J{1+hY
import com.adt.bo.Result; %3M(!X:[
8zP{Cmm
/** 2-Y%W(bEzs
* @author Joa >:%i,K*AM
*/ I2hX;pk,
publicinterface UserManager { In#V1[io
DBANq\
public Result listUser(Page page)throws $`W.9
`c ~Va/Yi
HibernateException; 3<LG~HWST
8;mn7 XX
} dVmI.A'nbp
-h%;L5oJ2,
4J
Bm|Pf(
}A3(g$8KR
!Sx}~XB<
java代码: 3YVG|Bc~_
rs2G{a
Wly-z$\
/*Created on 2005-7-15*/ )F4H'
package com.adt.service.impl; h<U<KO
Ymkk"y.w
import java.util.List; &;S.1tg
ES p)%
import net.sf.hibernate.HibernateException; teH $hd-q
s1.YH?A;
import org.flyware.util.page.Page; t"k6wv;Tq
import org.flyware.util.page.PageUtil; 2mN>7Tj:
WW82=2rJ9
import com.adt.bo.Result; zim]3%b*A;
import com.adt.dao.UserDAO; ^Lr)STh
import com.adt.exception.ObjectNotFoundException; Y+75}]B
import com.adt.service.UserManager; DP **pf%j
xtMN<4#E
/** xzTTK+D@
* @author Joa N+%E=D>
*/ :=WiT_M
publicclass UserManagerImpl implements UserManager { RO"c+|Py
E:/G!1
private UserDAO userDAO; $BKGPGmh
}UNRe]ft$
/** +U_> Bo
* @param userDAO The userDAO to set. Q= IA|rN
*/ 8##-fv]
publicvoid setUserDAO(UserDAO userDAO){ I)Y ^_&=
this.userDAO = userDAO; ~&B{"d
} @9~a3k|
VcKufV'
/* (non-Javadoc) 1CK}XLdr
* @see com.adt.service.UserManager#listUser F`KA^ZI
,DsqKXSU
(org.flyware.util.page.Page) rKEi1b
*/ +>mbBu!7
public Result listUser(Page page)throws Lsv[@Rl
]Tk3@jw+b
HibernateException, ObjectNotFoundException { #ky]@vyO
int totalRecords = userDAO.getUserCount(); l6Wa~ E
if(totalRecords == 0) \o3)\
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throw new ObjectNotFoundException , tJ%t#
dYV'<
("userNotExist"); S~fUR n
page = PageUtil.createPage(page, totalRecords); !i=LQUi.
List users = userDAO.getUserByPage(page); 8?#4<4Ql8
returnnew Result(page, users); Kcv7C{-/
} V)#se"GV
lj0"2@z3"E
} VL=. JwK
A8 V7\
O|j(CaF
1H sfCky{
?RL[#d+y
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 ):HjpJvF
4TcKs}z
询,接下来编写UserDAO的代码: &1)4B
3. UserDAO 和 UserDAOImpl: 1Q1NircJ
java代码: ,>% 2`Z)
A*#.7Np!"
1sp>UBG
/*Created on 2005-7-15*/ j}R!'m(P'
package com.adt.dao; eaLSq
&5>R>rnB
import java.util.List; *ub]M3O
88(h`RGMh
import org.flyware.util.page.Page; h?E[28QB
G q%q x4
import net.sf.hibernate.HibernateException; 3\_ae2GW
T(t@[U2^
/** kSx^Uu*
* @author Joa L1=+x^WQ
*/ %xZYIYKf
publicinterface UserDAO extends BaseDAO { BUT{ }2+K
2@K D
'^(
publicList getUserByName(String name)throws _h|rH
*ue-
x!"c
HibernateException; /Y$UJt
eF+:w:\h
publicint getUserCount()throws HibernateException; g-`HKoKe
C
"XvspJ
publicList getUserByPage(Page page)throws G|eY$5!i
rMRM*`Q2
HibernateException; ^<X+t&!z
a+A^njk
} +oa\'.~?
,#&\1Vxf
KwGk8$ U
VN!`@Ci/
S+(TRIjk
java代码: #'5|$ug[
):"Z7~j=
umPd+5i
/*Created on 2005-7-15*/ Q;r9>E!
package com.adt.dao.impl; 48;6C g
ct,B0(]
import java.util.List; X"_,#3Ko!
gc``z9@Xg
import org.flyware.util.page.Page; }uWIF|h~
2ghTAsUx9
import net.sf.hibernate.HibernateException; (gN[<QL
import net.sf.hibernate.Query; *J^l
r"%c
o5=1
import com.adt.dao.UserDAO; Q9,H0r-%
lS"g[O+
/** 69#mj*p@+
* @author Joa mS?.xu
*/ K@av32{
public class UserDAOImpl extends BaseDAOHibernateImpl Ln6\Iis
G.v zz-yG
implements UserDAO { _,*ld#'s
W/03L, 1
/* (non-Javadoc) k?r-%oJ7
* @see com.adt.dao.UserDAO#getUserByName hM}rf6B
_$s ;QI]x
(java.lang.String) pxm{?eBz
*/ %`*`HU#X
publicList getUserByName(String name)throws 1Rrp#E}
P<<?7_ ??
HibernateException { qKoD*cl)Za
String querySentence = "FROM user in class Uc
oVp}vl
kLc}a5;
com.adt.po.User WHERE user.name=:name"; %eJolztKZ
Query query = getSession().createQuery ,H6*9!Dv2
zxN,ys
(querySentence); cuv?[M
query.setParameter("name", name); kU uDA><1
return query.list(); +/!kL0[v
} +; /]'
\:>GF-Z(
/* (non-Javadoc) `qP <S
* @see com.adt.dao.UserDAO#getUserCount() "},0Cs
*/ ODS8bD0!i
publicint getUserCount()throws HibernateException { Md!L@gX6<
int count = 0; :r5DR`Rfm
String querySentence = "SELECT count(*) FROM K)NB{8 _
B[XVTok
user in class com.adt.po.User"; =W+ h.?
Query query = getSession().createQuery /u
hA\m(
uu08q<B5b)
(querySentence); TL^af-
count = ((Integer)query.iterate().next nR%ASUx:Y
06hzCWm#
()).intValue(); zj~(CNE
return count; =&Dt+f&
} "ecG\}R=
-nBb -y
/* (non-Javadoc) bbGSh|u+P
* @see com.adt.dao.UserDAO#getUserByPage luA k$Es
[!^Q_O
(org.flyware.util.page.Page) 8sMDe'
*/ +7yirp~`K
publicList getUserByPage(Page page)throws y2"PKBK\_
Xx.4K>j+j
HibernateException { 3O{*~D&n
String querySentence = "FROM user in class ?&qa3y)wX:
1oD1ia#
com.adt.po.User"; |jh&a+4W
Query query = getSession().createQuery 4k}3^.#
)-2sk@y
(querySentence); 9\2<#,R1q
query.setFirstResult(page.getBeginIndex()) 2oY.MQD7iW
.setMaxResults(page.getEveryPage()); 7d9kr?3(U
return query.list(); >F@qFPN]
} (~C_zG
c!,&]*h"k
} . X(^E
G)ppkH`qj
r'!HWR
E
cS+/
q?R)9E$h
至此,一个完整的分页程序完成。前台的只需要调用 X5s.F%Np!
VL^.7U
userManager.listUser(page)即可得到一个Page对象和结果集对象 kzMul<>sl
Yd}Jz
的综合体,而传入的参数page对象则可以由前台传入,如果用 Y}db<Cz
X
5|T[:m
webwork,甚至可以直接在配置文件中指定。 RQaB_bg7
pKSn
3-A
下面给出一个webwork调用示例: to}g4
java代码: Dt1v`T~=?
nC-=CMWWr
k,)xv?
/*Created on 2005-6-17*/ zWN/>~}U\
package com.adt.action.user; ,r$k79TI
M%*D}s-QE
import java.util.List; HR.^
y$IE
X@ zw;Se
import org.apache.commons.logging.Log; yH\3*#+
import org.apache.commons.logging.LogFactory; 'VgdQp$L$
import org.flyware.util.page.Page; M
@|n"(P
IJWUNKqo=
import com.adt.bo.Result; H2f!c{t$p
import com.adt.service.UserService; =[N=mC
import com.opensymphony.xwork.Action; x,CTB
79DzrLu
/** S5Hb9m&&
* @author Joa }rWEa^
*/ =H<I` J'
publicclass ListUser implementsAction{ |E%i
t?3M
~0;l\^
privatestaticfinal Log logger = LogFactory.getLog kAu-=X
]lT8Z-h@
(ListUser.class); ^Y;}GeA,
7WEh'(`
private UserService userService; kIC$ai6.
O\3
Lx
private Page page; |4$.mb.
8OS@gpz
privateList users; )[t zAaP7
(-<s[VnXP
/* Y/%(4q*'
* (non-Javadoc) GnX+.uQL|
* jTR>H bh
* @see com.opensymphony.xwork.Action#execute() 3MmpB9l#H
*/ (D\7EH\9,]
publicString execute()throwsException{ n@TK}?\UoR
Result result = userService.listUser(page); Su4&qY
page = result.getPage(); Aof)WKo
users = result.getContent(); R6(sWN-
return SUCCESS; \
F\ /<
} &:>3tFQSH
\?$`dA [
/** ;\N)RZ
* @return Returns the page. R m&^[mv
*/ Z[ NO`!<
public Page getPage(){ ;S&PLgZ
return page; mp!S<m
} .S5%Qa [uW
'-,$@l#
/** B4D#TlB
* @return Returns the users. H%nA"-
*/ 6-fdfU
publicList getUsers(){ pmWt7 }
return users; +jEtu[ ;
} 9}[UZN6
Q.U
wtH
/** '3p7ee&
* @param page Jw4#u5$$Z
* The page to set. ^vj}
*/ s~z~9#G(6
publicvoid setPage(Page page){ }&*wJ]j`L
this.page = page; *(,zPn,
} {
R`"Nk
'bd|Oww1u
/** s|`Z V^R
* @param users yd}1Mx
* The users to set. ?rJe"TOIy
*/ 8t)?$j$
publicvoid setUsers(List users){ @TQzF-%#7
this.users = users; o]@Mg5(8Q
} Q)IL]S
I[l8@!0
/** f} !Eu
* @param userService X([8TR
* The userService to set. <hV%OrBz-
*/ qk{+Y
publicvoid setUserService(UserService userService){ @W1F4HYds
this.userService = userService; 2Y7u M;8
} N|rB~
} baO'FyCs9&
9cnLf#
yrF"`/zv6|
SSAf<44e
hr/H vB
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, NQmdEsK
Wik8V 0(
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 lz [s
@2`$ XWD
么只需要: !U"?vS l
java代码: <k'%rz
uxOeD%Z>
[0?W>A*h
<?xml version="1.0"?> n/6qc3\5i
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork |>~pA}
}0oVIr
1.0//EN" "http://www.opensymphony.com/xwork/xwork- tW
-f_0a.
QFNw2:)
1.0.dtd"> [["az'Lrk?
IA;'5IF
<xwork> c gOkm}h
\Q!I;
<package name="user" extends="webwork- &cSZ?0R
RYyM;<9F
interceptors"> p.|M:C\xL
q2e=(]rKE{
<!-- The default interceptor stack name ZnAXb S
JC.nfxG@:
--> 0,]m.)ws
<default-interceptor-ref f.G"[p
Fl}{"eCF8
name="myDefaultWebStack"/> #/0d
n)uck5
<action name="listUser" M-V{(
\\)9QP?
class="com.adt.action.user.ListUser"> >3?p 23|;
<param I/hq8v~S
.Y5o&at6s
name="page.everyPage">10</param> ]2
<result l3:2f-H
skP'- ^F~
name="success">/user/user_list.jsp</result> "j/jhe6
</action> j[${h,p?
KQTv5|$?
</package> $1uT`>%
HZ[.,DuW
</xwork> ]99@Lf[^f
)>(ZX9diV
=k]2Ad
XI\P#"
T9\G,;VQ7/
DS|q(O=7~t
这样就可以通过配置文件和OGNL的共同作用来对page对象设置初值 OsV'&@+G>
O8k+R@
了。并可以通过随意修改配置文件来修改每页需要显示的记录数。 FaLc*CU
s4[PwD
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 A&S n^mw
vLs*}+f
c->.eL%
(b8ZADI*
rHp2I6.0a
我写的一个用于分页的类,用了泛型了,hoho w2) @o>w
0fog/c#q(
java代码: BMO &(g
e0ULr!p
Z</57w#-7
package com.intokr.util; wE3fKG.
LDY3Ya`6m
import java.util.List; hjq@.5
*t300`x
/** 0=k
* 用于分页的类<br> 6E{(_i
* 可以用于传递查询的结果也可以用于传送查询的参数<br> 2&zklXuo:
* (9Of,2]&E
* @version 0.01 X$*]$Ge>
* @author cheng ]@uuB\u
*/ * /^}
public class Paginator<E> { $'n?V=4
privateint count = 0; // 总记录数 ]P>c{
privateint p = 1; // 页编号 0{(5J,/BF
privateint num = 20; // 每页的记录数 qH(HcsgD
privateList<E> results = null; // 结果 dC>(UDC
,Bs/.htQj
/** tz9"#=}0
* 结果总数 tu' s]3RE
*/ abw5Gz@Ag
publicint getCount(){ T|-llhJ8
return count; )lU9\"?o
} @^.o8+Pp
DN;|?oNZ
publicvoid setCount(int count){ ]Q#k"Je
this.count = count; gKP=@v%-
} *)L~1;7j>
gu"@*,hL
/** yRR[M@Y
* 本结果所在的页码,从1开始 9v/=o`J#
* 'fYF1gR4
* @return Returns the pageNo. #$;}-*
*/ ^/I.? :+
publicint getP(){ gh `]OxA
return p; \ #N))gAQ
} ^p~QHS/
"(mF5BE-E
/** p,BoiYdi
* if(p<=0) p=1
tYp 185
* M<r]a{Yv
* @param p Gkm{b[
*/ W~FU!C?]
publicvoid setP(int p){ *|ef #-|D
if(p <= 0) 1&RB=7.h
p = 1; io UO0
this.p = p; P4:Zy;$v!
} 0),fY(D2T
DWS#q|j`"
/** (duR1Dz
* 每页记录数量 C]&/k_k
*/ F!g;}_s9
publicint getNum(){ nrR2U`
return num; 6mqp`x`
} QjKh#sU&
urg^>n4V]
/** (Q=:ln;kM
* if(num<1) num=1 bg5i+a,?
*/ g>
m)XY
publicvoid setNum(int num){ &3Lhb}m
if(num < 1) ??f,(om
num = 1; ZiPz~G0[^
this.num = num; \Vpv78QF;
} $Gcjm~
*z};&UsF{
/** I|wC`VgB
* 获得总页数 B`YD>oCN
*/ tRo` @eEX
publicint getPageNum(){ 9&{z?*
return(count - 1) / num + 1; sL,|+>7T^M
} -EP(/CS!
0\Tp/Ph
/** bB)$=7\
* 获得本页的开始编号,为 (p-1)*num+1 v\E6N2.S
*/ Zs8]A0$
publicint getStart(){ <7! "8e
return(p - 1) * num + 1; ,w
f6gmh8
} <fE^S
R@#xPv4o%
/** eVd:C8q
* @return Returns the results. G#ELQ/Q
*/ _St":9'uU
publicList<E> getResults(){ HL-'\wtl
return results; NLu[<u U*
} JXHf$k
P/xEn_*v
public void setResults(List<E> results){ BF 0#G2`h>
this.results = results; (b.4&P"0
} UCj:]!P
_GM?`
public String toString(){ >
H&v
StringBuilder buff = new StringBuilder P 5.@LN
MS:,I?
(); Dp4x\97O
buff.append("{"); uzT+,
buff.append("count:").append(count); %`~+^{Wp
buff.append(",p:").append(p); x4h.WDT$
buff.append(",nump:").append(num); 4 Dy1M}7
buff.append(",results:").append @R<z=n"
W.%p{wB|
(results); 9m)gp19YA
buff.append("}"); LG:d
return buff.toString(); XpYd|BvW
} e.^?hwl
M!i*DU+SE
} *sau['Ha
i6$HwRZm#
L2_[M'