Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 2.]~*7
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 PDhWFF
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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 $> ;a'f~
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自于Quake Wang的javaeye-core包的相应类,然后又做了很多修改 02,W~+d1
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分页支持类: iNXFk4
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java代码: ]s_@n!
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package com.javaeye.common.util; ^eobp.U
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import java.util.List; uNy!<u
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publicclass PaginationSupport { rfX=*mjt
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publicfinalstaticint PAGESIZE = 30; [NL -!
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privateint pageSize = PAGESIZE; SAy{YOLtl
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privateList items; !x8kB
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privateint totalCount; ,aWCiu}
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privateint[] indexes = newint[0]; ~~@y_e[N#l
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privateint startIndex = 0; @C=m?7O98
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public PaginationSupport(List items, int u3ST;
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totalCount){ o<nS_x
setPageSize(PAGESIZE); j$mz3Yk
setTotalCount(totalCount); "Vx6 #u@}
setItems(items); -zdmr"CA
setStartIndex(0); JL``iA
} &y\igX1
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public PaginationSupport(List items, int (7~%B"
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totalCount, int startIndex){ "|hlDe<
setPageSize(PAGESIZE); 6#vI;d[^
setTotalCount(totalCount); Cg^:jd
setItems(items); %jTw
setStartIndex(startIndex); (2tH"I
} xj7vI&u.
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public PaginationSupport(List items, int ?M~
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totalCount, int pageSize, int startIndex){ `,P
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setPageSize(pageSize); &r:=KT3
setTotalCount(totalCount); >:$"a
setItems(items);
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setStartIndex(startIndex); kT2Wm/L
} .`+yo0O:
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publicList getItems(){ Sc{Tq\t;%
return items; wPgDy
} &(7$&Q
59Nd}wPO;
publicvoid setItems(List items){ "k, K ~@}
this.items = items; I)lC{v
} abSq2*5K
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publicint getPageSize(){ 32^#RlSu8
return pageSize; x_W3sS]ej
} p6Gcts?,
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publicvoid setPageSize(int pageSize){ P63
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this.pageSize = pageSize; cm,4&x6
} Qi^;1&
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publicint getTotalCount(){ C=[Ae,
return totalCount; U{HML|
} y]^#$dK(z
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publicvoid setTotalCount(int totalCount){ q)k{W>O
if(totalCount > 0){ Y;g% e3nu
this.totalCount = totalCount; 0Az/fzJlz
int count = totalCount / Man^<T%F
2rmNdvvrk
pageSize; bBG/gQ
if(totalCount % pageSize > 0) .R\p[rv&
count++; uQ^hV%|"
indexes = newint[count]; 2qXo{C3
for(int i = 0; i < count; i++){ ;AJ<
LC
indexes = pageSize * +(y>qd
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i; 3fl7~Lw,
} ,(;5%+#n
}else{ N3Z@cp
this.totalCount = 0; !xymoiArp
} L20rv:W$h
} LyV#j>gD
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publicint[] getIndexes(){ NnP.k7m)
return indexes; K-6p'|
} )WmZP3$^TX
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publicvoid setIndexes(int[] indexes){ zsQF,7/}B
this.indexes = indexes; %z2oDAjX
} 6&mWIk^VC
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publicint getStartIndex(){ $ hoYkA
return startIndex; j3LNnZY
} zu<>"5}]
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publicvoid setStartIndex(int startIndex){ wR(ttwxK3
if(totalCount <= 0) 8;0^'Qr8
this.startIndex = 0; GRy4cb2
elseif(startIndex >= totalCount) )%BT*)x
this.startIndex = indexes `BpCRKTG
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[indexes.length - 1]; C`pan /t
elseif(startIndex < 0) PYaOH_X.
this.startIndex = 0; }FZp840
else{ D"'#one
this.startIndex = indexes i6F P[6H1
jWhD5k@v
[startIndex / pageSize]; sE}sE=\
} dbd"pR 8v
} IN>TsTo
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publicint getNextIndex(){ WVj&0
int nextIndex = getStartIndex() + )|Jr|8
7;~2e
pageSize; (Y&R0jt
if(nextIndex >= totalCount) UX?X]ZYVR
return getStartIndex(); R+C+$?4NG
else JW2W>6Dgv[
return nextIndex; dfnX!C~6 \
} gr[D!D>
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publicint getPreviousIndex(){ dr}O+7_7%-
int previousIndex = getStartIndex() - !P+~c0DF
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pageSize; Idt@Hk5<&
if(previousIndex < 0) ]rKH|i
return0; ^o,y5,
else >I{4
return previousIndex; 4c~*hMry
} 3~#Z E;>#
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} `W6:=H
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抽象业务类 yN%3w0v
java代码: KBp!zSl
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/** btJ,dpir
* Created on 2005-7-12 e<&_tx
*/ hlYS=cgY=
package com.javaeye.common.business; OLhWkN,qA
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import java.io.Serializable; <T4 7kL I
import java.util.List; p7?CeyZ-V
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import org.hibernate.Criteria; I_R5\l}O+D
import org.hibernate.HibernateException; w yuJSB
import org.hibernate.Session;
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import org.hibernate.criterion.DetachedCriteria; OgzGkc@A
import org.hibernate.criterion.Projections; oRtY?6^$
import )j)y5_m
I\F=s-VVY
org.springframework.orm.hibernate3.HibernateCallback; (9'G
import |TNiKy
.~V".tZV[
org.springframework.orm.hibernate3.support.HibernateDaoS K{`2jK#
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upport; =]2RC1#}e
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import com.javaeye.common.util.PaginationSupport; * 7zN
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public abstract class AbstractManager extends wAj(v6
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HibernateDaoSupport { 3>:zo:;
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privateboolean cacheQueries = false; z!Pdivx
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privateString queryCacheRegion; [h2p8i'o
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publicvoid setCacheQueries(boolean :a^,Ei-&
"cz]bCr8
cacheQueries){ :BrnRW64
this.cacheQueries = cacheQueries;
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} KWZNu&)
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publicvoid setQueryCacheRegion(String )4o=t.O\K
/n<Ncf
queryCacheRegion){ %lqG* dRx0
this.queryCacheRegion = yU&g|MV_
CH R?i1e
queryCacheRegion; 6u]OXPA|
} ~]t2?SqNm
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publicvoid save(finalObject entity){ 3!L<=X
getHibernateTemplate().save(entity); uvK%d\d
} Q/9vDv
5IF~]5s
publicvoid persist(finalObject entity){ ]qP}\+:
getHibernateTemplate().save(entity); x.4)p6
} b\uB
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publicvoid update(finalObject entity){ 0T{Y_IG
getHibernateTemplate().update(entity); q'8@0FT0
} [ QL<&:s&
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publicvoid delete(finalObject entity){ ~>-;(YU"t
getHibernateTemplate().delete(entity); KL_}:O68
} . L6@Rs
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publicObject load(finalClass entity, EA{*%9 A
@^4M~F%
finalSerializable id){ OQb9ijLeK
return getHibernateTemplate().load y.]]V"'2
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(entity, id); PHL@1K{)
} l$~bkVNL
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publicObject get(finalClass entity, r#w_=h)
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finalSerializable id){ HkB<RsS$p_
return getHibernateTemplate().get umn~hb5O
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(entity, id); 7wEG<,D
} WM l ^XZO
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publicList findAll(finalClass entity){ rxk{Li<9
return getHibernateTemplate().find("from S7>gNE;%]u
1E_Ui1 [
" + entity.getName()); Nn7@+g)
} x{o5Ha{
_5`S)G{
publicList findByNamedQuery(finalString 9F1stT0G%
)P+GklI{4
namedQuery){ * CGdfdxW
return getHibernateTemplate IGV.0l
;<R_j%*
().findByNamedQuery(namedQuery); R*fR?
} t"vO&+x
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publicList findByNamedQuery(finalString query, :Aiu!}\
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finalObject parameter){ ?t P/VL
return getHibernateTemplate (,y/nc=GN
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().findByNamedQuery(query, parameter); {S(T1ua
} '+tT$k
/ {~h?P}
publicList findByNamedQuery(finalString query, U {!{5l:
; O0rt1
finalObject[] parameters){ PdBhX
return getHibernateTemplate k(+u"T
WfO$q^'?DP
().findByNamedQuery(query, parameters); 8{t&8Ql n
} 0Ch._~Q+20
}"k(kH
publicList find(finalString query){ MoHvXp;X
return getHibernateTemplate().find gi >{`.]
+N_%|!F-c
(query); M3`A&*\;
} nQmYeM
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publicList find(finalString query, finalObject K 5[ 3WHQ
[nD4\x+
parameter){ FR"^?z?}p
return getHibernateTemplate().find Z+7S,M
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(query, parameter); Ij_`=w<
} 5Oq ;V:7
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public PaginationSupport findPageByCriteria o#6}?g.
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(final DetachedCriteria detachedCriteria){ _"V0vV
return findPageByCriteria bnQO}G
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); T7'$A!c
} t57b)5{FM
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public PaginationSupport findPageByCriteria RoZV6U~
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(final DetachedCriteria detachedCriteria, finalint A[bxxQSP\H
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startIndex){ hg @Jpg
return findPageByCriteria C-Z,L#
|?kH]Trr
(detachedCriteria, PaginationSupport.PAGESIZE, p2K9R4
.@Cshj
startIndex); ~T~v*'_h
} %*nZ,r
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public PaginationSupport findPageByCriteria (tv h9o
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(final DetachedCriteria detachedCriteria, finalint W%ud nJ
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pageSize, R7i*f/m
finalint startIndex){ lLhCk>a
return(PaginationSupport) K~]jXo^M
hj4Rr(T
getHibernateTemplate().execute(new HibernateCallback(){ U?QO'H5
publicObject doInHibernate x3Uv&
V|)>
(Session session)throws HibernateException { /L.a:Er$
Criteria criteria = ZE^de(Fm
D }\`5L<
detachedCriteria.getExecutableCriteria(session); $H^6I8>
int totalCount = k$UBZ,=iC
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((Integer) criteria.setProjection(Projections.rowCount e9d~Xi16KY
DKZ69^
()).uniqueResult()).intValue(); Li2)~4p><
criteria.setProjection "{k3~epYaN
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(null); gT.-Cf{
List items = }/VHeHd
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criteria.setFirstResult(startIndex).setMaxResults fHigLL0B
&a`-NRU#
(pageSize).list(); Aq"_hjp
PaginationSupport ps =
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new PaginationSupport(items, totalCount, pageSize, ( ;"ICk&
4Qv|Z+$i
startIndex); i"'k|TGW^
return ps; Y%faf.$/9
} .#n?^73
}, true); =N=,;<6%A
} %Y@3)
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public List findAllByCriteria(final
lcr=^
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DetachedCriteria detachedCriteria){ 5?b9[o+D
return(List) getHibernateTemplate
; H3kb
+
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().execute(new HibernateCallback(){ rdb%/@.-
publicObject doInHibernate oVu>jO:.
v zn/waw
(Session session)throws HibernateException { aQ)9<LsI
Criteria criteria = vmoqsdZ/
4MM#\
detachedCriteria.getExecutableCriteria(session); 1)r1/0
return criteria.list(); Cxh9rUe.
} \R<yja
}, true); O^f@ g l
} 1kpI?Plki
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public int getCountByCriteria(final t`LH\]6@
{[$p}#7Y
DetachedCriteria detachedCriteria){ PQfx0n,
Integer count = (Integer) tly:$;K
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getHibernateTemplate().execute(new HibernateCallback(){ qg>i8V
publicObject doInHibernate 53L)+\7w
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(Session session)throws HibernateException { dWp4|r
Criteria criteria = I[&!\Me[+w
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detachedCriteria.getExecutableCriteria(session); WaHTzIa[
return 83S],L
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criteria.setProjection(Projections.rowCount mV;7SBoT
Jjy}m0)#W_
()).uniqueResult(); 6s Pd")%G
} We" "/X
}, true); .z_^_@qdm
return count.intValue(); PKwx)!
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} r2Q"NVw
} p0@iGyd
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@ O%m,
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用户在web层构造查询条件detachedCriteria,和可选的 xd>2TW l#
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 >`6^1j(3
^c=@2#^\
PaginationSupport的实例ps。 mX<D]Z< k
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ps.getItems()得到已分页好的结果集 au GN~"n^
ps.getIndexes()得到分页索引的数组 @
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ps.getTotalCount()得到总结果数 %D&FnTa
ps.getStartIndex()当前分页索引 p,xM7V"O)
ps.getNextIndex()下一页索引 s_RYYaM
ps.getPreviousIndex()上一页索引 .d.7D ]Yn
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 i~\gEMaO
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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 ,PY<AI^59
FCI38?`%
一下代码重构了。 | WDX@Q
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我把原本我的做法也提供出来供大家讨论吧: NMOTWA}2
;7qk9rz4
首先,为了实现分页查询,我封装了一个Page类: 60hf)er
java代码: 8_KXli}7=
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/*Created on 2005-4-14*/ @UvjJ
package org.flyware.util.page; bcOX/
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/** ,E/vHI8
* @author Joa 5ptbz<Xv
* 654PW9{(
*/ M`"2;
publicclass Page { %d*}:295
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== mO&
/** imply if the page has previous page */ %zY3,4~
privateboolean hasPrePage; :?lSa6de
slw^BK3t
/** imply if the page has next page */ G|H\(3hHLZ
privateboolean hasNextPage; #&DJ3(T
.%D] z{''
/** the number of every page */ `L:wx5?
privateint everyPage; 4;%=ohD:!
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/** the total page number */ eYS
privateint totalPage; @ '<lD*W
vn|X,1o
/** the number of current page */ 1OJ:Vy}n
privateint currentPage; v3`J~,V<
6~D:O?2
/** the begin index of the records by the current F7=a|g
|n]^gTJt
query */ 3{,Mpb@
privateint beginIndex; egKYlfe"
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/** The default constructor */ &
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public Page(){ #r0A<+t{T
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} e?F r/n
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/** construct the page by everyPage Cvi-4
* @param everyPage ~>)cY{wE_
* */ 9/^4W.
public Page(int everyPage){ _3ZZ-=J:=*
this.everyPage = everyPage; !'n+0
} $8X?|fV)
ISOPKZ#F
/** The whole constructor */ [NC^v.[1[
public Page(boolean hasPrePage, boolean hasNextPage, V$^x]z
T,jxIFrF
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int everyPage, int totalPage, IHf
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int currentPage, int beginIndex){ XBi@\i=
this.hasPrePage = hasPrePage; Y|KX:9Y@
this.hasNextPage = hasNextPage; YW>|gE
this.everyPage = everyPage; Jd/5Kx
this.totalPage = totalPage; )V~<8/)
this.currentPage = currentPage; FL0[V,
this.beginIndex = beginIndex; @4hxGk=
} ^8E/I]-
awo=%vJ&
/** mrk Q20D
* @return 6lsU/`.
* Returns the beginIndex. 9?l(
}S`
*/ #_4L/LV
publicint getBeginIndex(){
2VMau.eQ
return beginIndex; ;I]TM#qGF
} @v@'8E Q
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/** a]$KI$)e
* @param beginIndex Hq6VwQu?
* The beginIndex to set. m6aoh^I
*/ Po9 3&qE
publicvoid setBeginIndex(int beginIndex){ WY0u9M4
this.beginIndex = beginIndex; Ab8~'<F$B
} CM8WI~
()3+!};
/** gO_^{>2
* @return sRt|G
* Returns the currentPage. ]!0 BMZmf
*/
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publicint getCurrentPage(){ dax|4R
return currentPage; l&U3jeW-o
} Q
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)bPwB.} kq
/** 7q$9\RR5
* @param currentPage ]^ZC^z;H
* The currentPage to set. =@w};e#D
*/ #d(6q$IE
publicvoid setCurrentPage(int currentPage){ Wb/@~!+i`
this.currentPage = currentPage; ]:m*7p\uk
} ;bkS0Vmg
D;d'ss;
/** ,7>_Lp_v
* @return kd!f/'E!
* Returns the everyPage. &hjrJ/'^
*/ :t^=~xO9
publicint getEveryPage(){ \'BKI;
return everyPage; )u3<lpoTy
} rbQA6_U 5A
aH,0+ |
/** Hagj^8
* @param everyPage ]
M_[*OAb
* The everyPage to set. ]V><gZ
*/ *N< 22w
publicvoid setEveryPage(int everyPage){ 78y4nRQ*
this.everyPage = everyPage;
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} Kd7OnU
2R:['QT
/** 3U1xKF
* @return |F9/7 z\5+
* Returns the hasNextPage. 4Q_2GiF_
?
*/ X
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publicboolean getHasNextPage(){ AP/tBCeM
return hasNextPage; f<0-'fGJd
} 1UxRN7
1u)I}"{W>
/** &[23DrI8
* @param hasNextPage yBs
* The hasNextPage to set. b`18y cVME
*/ B5J=q("P
publicvoid setHasNextPage(boolean hasNextPage){ zx0{cNPK5
this.hasNextPage = hasNextPage; wzP>Cq
} FkKx~I:
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/** AR/`]"'
* @return z4_>6sf{
* Returns the hasPrePage. z`f1|Ok
*/ ,v>P05
publicboolean getHasPrePage(){ 611:eLyy&l
return hasPrePage; spd>.Cm`
} jJ|O]v$N
XZIj' a0d
/** +r4^oT[-
* @param hasPrePage 1_XdL?h#o
* The hasPrePage to set. S : 9zz
*/ 6W#M[0
publicvoid setHasPrePage(boolean hasPrePage){ .P-@ !Q5*
this.hasPrePage = hasPrePage; A4 o'EQ?~
} \BUr2]
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/** n#bC,
* @return Returns the totalPage. N[ E
t
* U6n%rdXJ=
*/ N\<M4fn
publicint getTotalPage(){ Ol D]*=.cO
return totalPage; mqw&SxU9
} *%\z#Bje@
n\wO[l)
/** ]"{K5s7
* @param totalPage 6\/C]![%
* The totalPage to set. /<
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*/ I tp7X
publicvoid setTotalPage(int totalPage){ +hV7o!WxC
this.totalPage = totalPage; YM/GSSq
} 7L? ~;;L$
q<D'"7#.
} |jO&qT]{
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kImS'i{A
yA
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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 WFsa8qv
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个PageUtil,负责对Page对象进行构造: G>d@lt
java代码: ,*}SfCon
AQQeLdTq
qOqQt=ObU
/*Created on 2005-4-14*/ T&fqn!i
package org.flyware.util.page; 7rbl+:y2
p4*VE5[?_+
import org.apache.commons.logging.Log; NYm2fFPc
import org.apache.commons.logging.LogFactory; +F]X
b'3w.%^
/** /{."*jK
* @author Joa ~(~fuDT~O
* -;Y*;xe
*/ 1I<D
`H%
publicclass PageUtil { h%8[];*DpN
am]$`7R5d
privatestaticfinal Log logger = LogFactory.getLog Ze~^+ EE
_%?}e|epy
(PageUtil.class); Pe6MDWR
)}0(7z
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/** ]bz']`
* Use the origin page to create a new page {r?O>KDQf(
* @param page T<=Ci?C
v
* @param totalRecords d OQU#5
* @return sk5h_[tK
*/ PO%Z.ol9
publicstatic Page createPage(Page page, int @T0F }(k
K?+iu|$&
totalRecords){ s5_[[:c=^
return createPage(page.getEveryPage(), f"\G"2C
66NJ&ac
page.getCurrentPage(), totalRecords); %5?qS`/c(
} rvgArFf}]
t:B~P,r
/** j"{|* _6E_
* the basic page utils not including exception ~Gx"gK0
9*pH[vH
handler 56T<s+X>
* @param everyPage !C]0l
* @param currentPage #EQwl6
* @param totalRecords Xxhzzm-B
* @return page FH:^<^M
*/ 8 h
publicstatic Page createPage(int everyPage, int ByqB4Hv2
?:73O`sX:
currentPage, int totalRecords){ sOQF_X(.x
everyPage = getEveryPage(everyPage); 8@pY:AY
currentPage = getCurrentPage(currentPage); gmtp/?>e
int beginIndex = getBeginIndex(everyPage, MHar9)$}
US3rkkgDO
currentPage); //T1e7)
int totalPage = getTotalPage(everyPage, QT)D|]bH
X!#rw= Q
totalRecords); M+4>l\
boolean hasNextPage = hasNextPage(currentPage, W?is8r:
6%?bl{pNn
totalPage); I.#V/{J
boolean hasPrePage = hasPrePage(currentPage); CEbZj
z|
>#~!03
returnnew Page(hasPrePage, hasNextPage, H?A&P4nZ
everyPage, totalPage, 5~)m6]-6
currentPage, TrA&yXXL
{6}H}_(]
beginIndex); Z{&dzc
}
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G?Fqm@J{XT
privatestaticint getEveryPage(int everyPage){ YB?yi( "yL
return everyPage == 0 ? 10 : everyPage; g>].m8DZ'
} ?VUW.-
A6-K~z^
privatestaticint getCurrentPage(int currentPage){ +Wgp~$o4
return currentPage == 0 ? 1 : currentPage; 9Q)9*nHe
} Qy< ~{6V
NmbA~i
privatestaticint getBeginIndex(int everyPage, int )o4B^kq
/O@TqH
currentPage){ z''ITX)oG
return(currentPage - 1) * everyPage; 8nKZ
} /<"<N<X
&:Mk^DH5
privatestaticint getTotalPage(int everyPage, int kF,_o/Jc
^)wTCkH&y
totalRecords){ QV&yVH=Xs
int totalPage = 0; }fqz8'E9
hzR1O(
if(totalRecords % everyPage == 0) (j>a?dKDS
totalPage = totalRecords / everyPage; xMOq/")
else #Cy9E"lP
totalPage = totalRecords / everyPage + 1 ; c}$C=s5 h}
ON()2@Y4
return totalPage;
lxVA:tz0
} V1h&{D\"
L'A>IBrz
privatestaticboolean hasPrePage(int currentPage){ =uG}pgh0
return currentPage == 1 ? false : true; Pjvzefp
} K*"Wq:T;B
Gt|m;o
privatestaticboolean hasNextPage(int currentPage, kuX{2h*`
bx XNv^
int totalPage){ 45
\W%8
return currentPage == totalPage || totalPage == v-utDQT3
Mtw7aK
0 ? false : true; VMZUJ2Yj/&
} O~udlVn<6
s%Y8;D,~+
WR<,[*Mv^
} K6BP~@H_D
9|{t%F=-
f6$$e+
2d60o~E
Md5|j0#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。 azCod1aL{
C{<dzooz
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 @
=XJ<
8N,mp>~
做法如下: #
9@K
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 <aRsogu"P
c|2+J:}p
的信息,和一个结果集List: d"nms\=p
java代码: ;i>(r;ZM
!8@8
tupAU$h?!
/*Created on 2005-6-13*/ $p)e.ZMgE
package com.adt.bo; t}X+P`Ovq
G^W'mV$xl
import java.util.List;
Sa 8T'%W
gK_#R]
import org.flyware.util.page.Page; UV#DN`%n
E
5N9.th
/** 'mm~+hp
* @author Joa I*`;1+`
*/ 87ptab@
publicclass Result { gnWEsA\!
xhw0YDGzf
private Page page; 3DX@ggE2
KGP *G
BZr
private List content; VC.zmCglo^
E06)&tF
/** +d'1
* The default constructor (/e[n.T
*/ + :;6kyM6X
public Result(){ >^bSjE
super(); Rz:1(^oA
} ' &<saqA
K]H [A,
/** MnBHm!]&
* The constructor using fields iL8:I)z
* Rl[SqmnI)@
* @param page myqQqVW
* @param content `+]e}*7$f
*/
PE&$2(
public Result(Page page, List content){ #'fQx`LV
this.page = page; |TQa=
this.content = content; 0kxe5*-|
} wfq}NK;
* amZ
/** :} N;OS _
* @return Returns the content. ,#8H9<O9t
*/ kB]?95>Wx
publicList getContent(){ 7f]O /
return content; B]wfDUG
} j*L-sU
wak`Jte=}m
/** kPezR:
31
* @return Returns the page. Gi Max
*/ @tVl8]y
public Page getPage(){ _[{oK G^u
return page; \(`,z}Ht _
} G4{TJ,~
CW'<Nh
/** Po7oo9d
* @param content 4mwLlYZ
* The content to set. 2|D<0d#W
*/ my*E7[
public void setContent(List content){ I!Uj~jV
this.content = content; .v[!_bk8C
} ~09k IO)
m:5x"o7)ln
/** l^;=0UR_
* @param page =0mXTY1
* The page to set. G4QsR7
*/ #bCzWg
publicvoid setPage(Page page){ u=&$Z
this.page = page; ]:Sb#=,!&!
} 3Nk
)
} #p/'5lA&j
eDL0Vw
mL]5Tnc
/A>1TPb09"
/9(8ML#E
2. 编写业务逻辑接口,并实现它(UserManager, *(j-jbA
*%jd>e7d
UserManagerImpl) j\TS:F^z
java代码: Qvm[2mb
H;Cv]-
QR*{}`+l
/*Created on 2005-7-15*/ Ct pc]lJ}
package com.adt.service; N7}yU~j^
dY'>'1>P
9
import net.sf.hibernate.HibernateException; K?X
6@u|h
^|lG9z%Foy
import org.flyware.util.page.Page; MB3
N3,yL
*}Nh7>d(
import com.adt.bo.Result; :B1a2Y^"
(m&''yaH
/** ;%Rp=&J
* @author Joa 'Z`fZ5q
*/ #PZBh
publicinterface UserManager { T(iL#2^
?PDrj/: *
public Result listUser(Page page)throws -`d(>ok
H'wh0K(
HibernateException; XYHVw)
#Q$`3rr
} =*Y=u6?
r:9H>4m
tqT-9sEXX.
2~q(?wY
5H
|<h
java代码: $-;x8O]u
MD=VR(P?eq
hP26 Bb1
/*Created on 2005-7-15*/ eKek~U&
package com.adt.service.impl; wVY;)1?
z{dn
import java.util.List; jN^09T49
/S\y-M9
import net.sf.hibernate.HibernateException; v}-j ls
lp%i%*EQ*
import org.flyware.util.page.Page; "f3KE=cUm
import org.flyware.util.page.PageUtil; M}W};~V2ng
dI|`"jl#
import com.adt.bo.Result; ky98Bz%
import com.adt.dao.UserDAO; mB]Y;R<
import com.adt.exception.ObjectNotFoundException; o= N_0.
import com.adt.service.UserManager; y6!Zt}m
x8wal[6
/** kFF)6z:2
* @author Joa BdZO$ALXL
*/ )XAD#GYM
publicclass UserManagerImpl implements UserManager { 6
w:@i_2^
j2"Y{6c
private UserDAO userDAO; *^5..0du
4yu ^cix(
/** 0kB!EJ<OdG
* @param userDAO The userDAO to set. 8{Id+Q>Vo,
*/ B[rxV
publicvoid setUserDAO(UserDAO userDAO){ 9AROvq|#
this.userDAO = userDAO; 9#AsSbBpf
} Y8yRQz u
KU}HVM{
/* (non-Javadoc) -O=a"G=
* @see com.adt.service.UserManager#listUser h.W;Dmf6]
;qF#!Kb5
(org.flyware.util.page.Page) ,3{z_Rax-
*/ %Pb 5PIk4
public Result listUser(Page page)throws hA81(JWG
ZP&"[_
HibernateException, ObjectNotFoundException { }Rc8\,
int totalRecords = userDAO.getUserCount(); fYzOT,c
if(totalRecords == 0) >cPB:kD'
throw new ObjectNotFoundException w*Gv#B9G
sgn,]3AUq
("userNotExist"); Svmyg]
page = PageUtil.createPage(page, totalRecords); ?wR;"
List users = userDAO.getUserByPage(page); Hop$w
returnnew Result(page, users); t?0D* !D
} >_biiW~x :
.wD>0Ig
} qG/a5i
J(\"\Z
3d.JV'C'c
q)ygSOtj
KsGS s9
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 FV/X&u8~
d{f3R8~Q.
询,接下来编写UserDAO的代码: KZL5>E
3. UserDAO 和 UserDAOImpl: X?b]5?K;r
java代码: z+1#p.F$@
}B_n}<tjD
qB_MDA
/*Created on 2005-7-15*/ Wx&AY"J
package com.adt.dao; 1V?}";T
:rb<mg[
import java.util.List; i_ 4FxC4
e:V(kzAY;
import org.flyware.util.page.Page; <> f
f{lg{gA(
import net.sf.hibernate.HibernateException; *&B*/HAN
`-4c}T
/** WZRrqrjq
* @author Joa pN&Dpz^
*/
Nora<
publicinterface UserDAO extends BaseDAO { uj&^W[s
7I`e5\ u
publicList getUserByName(String name)throws MyuFZ7Q4$
T"t3e=xA
HibernateException; zb~!>
QIz{
-<}_K,Ky`
publicint getUserCount()throws HibernateException; gyieS Xz[
PF@<>NO+W
publicList getUserByPage(Page page)throws oj@B'j
Te2XQU2,F
HibernateException; D(}v`q{Y
.0#?u1gXsX
} 6+FmYp
1I KDp]SN
6ndt1W
z
" 9 h]P^
;hmy7M1%
java代码: Az6f I*yP
I9ubV cV8
&K)c*'l
/*Created on 2005-7-15*/ >&e|ins^N
package com.adt.dao.impl; ^{-J Y
#=5/D@
import java.util.List; A"#Gg7]tl'
V;~W,o !
import org.flyware.util.page.Page; DK&J"0jz,
*xM4nUu<~
import net.sf.hibernate.HibernateException; d;9 X1`"
import net.sf.hibernate.Query; a*NcL(OC
%IW=[D6Tg
import com.adt.dao.UserDAO; {*`qL0u]^
$=TFTSO
/** Sh*LD
QL<?
* @author Joa }9aYU;9D
*/ 5"c#OU
public class UserDAOImpl extends BaseDAOHibernateImpl HzF
OCa74)(
implements UserDAO { GG5wiN*2S
SQ]&nDd
/* (non-Javadoc) &o=
#P2Qd
* @see com.adt.dao.UserDAO#getUserByName -k|r#^(G2
; ob>$ _
(java.lang.String) w{UVo1r:
*/ 6OF&Q`*4
publicList getUserByName(String name)throws >> Z.]
fDNiU"
HibernateException { .v9 #|d d+
String querySentence = "FROM user in class MVs@~=
-[|R\'i
com.adt.po.User WHERE user.name=:name"; y>3Zh5=
Query query = getSession().createQuery Jv %,v?
.EM0R\q
(querySentence); <3m_}
=\
query.setParameter("name", name); %# ?)+8"l
return query.list(); R7r` (c!
} WId"2W3M
$d3al%Uo
/* (non-Javadoc) <La$'lG4J
* @see com.adt.dao.UserDAO#getUserCount() 3vfm$sx@
*/ >k"Z'9l
publicint getUserCount()throws HibernateException { y4PR&^l?g
int count = 0; OS;qb:;
String querySentence = "SELECT count(*) FROM !}<d6&!py
\1cay#X
user in class com.adt.po.User"; _dky+ E
Query query = getSession().createQuery 5R\{&
$A]2Iw!&
(querySentence); l\xcR]O
count = ((Integer)query.iterate().next ;gLHSHEA
IL;JdIa
()).intValue(); >?aPXC
return count; [-5%[ty9X
} C62:G+W&o
V`7
/* (non-Javadoc) M3P\1
* @see com.adt.dao.UserDAO#getUserByPage : 8dQ8p;
un([3r
(org.flyware.util.page.Page) }N[|2nR'
*/ ix4O-o{
publicList getUserByPage(Page page)throws & mwQj<Z
N^</:R
HibernateException { < %@e<,8
String querySentence = "FROM user in class 4efIw<1_
(#I$4Px{
com.adt.po.User"; [rk*4b ^s
Query query = getSession().createQuery 7[z^0?Pygf
Q+@/.qJ
(querySentence); z ntvKOIh
query.setFirstResult(page.getBeginIndex()) E)w6ZwV
.setMaxResults(page.getEveryPage()); &!i'Q;q
return query.list(); cxX/ b,
} U}f"a!
1i=lJmr
} t&|M@Ouet
QIl=Ho"c
,~8&0p
WxPu{N
D+4oV6}~
至此,一个完整的分页程序完成。前台的只需要调用 f2h`bO
ul(pp+%S
userManager.listUser(page)即可得到一个Page对象和结果集对象 )<ig6b%
{7d(B1[1
的综合体,而传入的参数page对象则可以由前台传入,如果用 PmjN!/
5>r2&72=
webwork,甚至可以直接在配置文件中指定。 ?,XrZRF
\B/!}Tn;
下面给出一个webwork调用示例: g\.O5H9Od
java代码: vw~=z6Ka
,I|3.4z
C" SG':
/*Created on 2005-6-17*/ o?,c#g
package com.adt.action.user; ] 6Y6q])Z
fEJF3<UF&
import java.util.List; {!0f.nv
f]sc[_n]
import org.apache.commons.logging.Log; D( \c?X"
import org.apache.commons.logging.LogFactory; :<p3L!?8y
import org.flyware.util.page.Page; E\5Cf2Ox
%ztv.K(8
import com.adt.bo.Result; t~v_k\`{
import com.adt.service.UserService; jjT)3
c:J[
import com.opensymphony.xwork.Action; X_HU?Q_N
MA1y@
/** /OD@Xl];K
* @author Joa #1)#W6 h\
*/ ~J:qG9|]}
publicclass ListUser implementsAction{ byJR6f
OC6v%@xa
privatestaticfinal Log logger = LogFactory.getLog [,yYr
-|DBO0q
(ListUser.class); jvQpfd
mufXM(
private UserService userService; 'z9}I
#
k0bDEz.X
private Page page; +/>XOY|Ie
^aI$97Li
privateList users; bQgtZHO
GR,gCtG+L
/* 7Z<
2`&c7
* (non-Javadoc) M@]@1Q.p
* O77^.B
* @see com.opensymphony.xwork.Action#execute() i%GNmD
*/ TCI)L}L|
publicString execute()throwsException{
*v#Z/RrrA
Result result = userService.listUser(page); &BxZ}JH=k
page = result.getPage(); \R[f< K%
users = result.getContent(); g3| 62uDF
return SUCCESS; ~.$ca.Gf
} }X9G(`N(}
@(CJT-Ak
/** \C kb:
* @return Returns the page. AhU
*/ "IJ 9vXI
public Page getPage(){ 63SmQsv
return page; LMRq.wxbbB
} }u+cS[#-
M*Ri1
/** m't8\fo^w
* @return Returns the users. s x2\
*/ ]$)U~)T
iW
publicList getUsers(){ dmYgv^t
return users; E`b<^l`
} i4\DSQJ
om{aws;
/** .R_-$/ZP
* @param page ;Dp<|n
* The page to set. /DX6Hkkj %
*/ \t
^9UN
publicvoid setPage(Page page){ <"Yx}5n.
this.page = page; ozkmZ;
} j/, I)Za
y eWB.M~X
/** $q g/8G
* @param users ]SL0Mn g8
* The users to set. g|<$\}
*/ !Q=xIS
publicvoid setUsers(List users){ }{F1Cr
this.users = users; /3o@I5
} I`q"
o{OY1 ;=6
/** S?u@3PyJm
* @param userService (3N;-
* The userService to set. >#|%y>g .o
*/ }TG=ZVi
publicvoid setUserService(UserService userService){
K2D,
*w
this.userService = userService; ~#|Pe1Y
} <CN+VXF
} :y^%I xs{1
-GT&46hX
VH6J
@m
h`pXUnEZ
&5Huv?^a'
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, /EV _Y|(-
Mb'Tx
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 5?-@}PL!Y
MXrh[QCU)
么只需要: uolEX+
java代码: />dYk Iv
2-_d~~O1N
h5}:>yc
<?xml version="1.0"?> h.)o4(bO
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork $m;DwlM
X^)vZL?
1.0//EN" "http://www.opensymphony.com/xwork/xwork- oETl?Vt
|6!L\/}M%
1.0.dtd"> $kd9^lj#[
#9(L/)^
<xwork> %SJFuw"
E[2xo/H
<package name="user" extends="webwork- x#}{z1op9
G$-[(eu-
interceptors"> O^KIB%}fu
+|zcjI'=O
<!-- The default interceptor stack name l1eF&wNC
[xH Hm5$
--> eKW^\
<default-interceptor-ref < m/@_"
KYR64[1
name="myDefaultWebStack"/> -;j
'=?
y8$I=
<action name="listUser" cA{7*=G?
oP_}C[
class="com.adt.action.user.ListUser"> N'~l,{
<param `]j:''K
aM|;3j1p
name="page.everyPage">10</param> DLd1Cl:"~:
<result JXq l=/%
9z kRwrQ
name="success">/user/user_list.jsp</result> \`Ow)t:
</action> !U4<4<+
#}S<O_
</package> >*Ctp +X@
L&hv:+3N
</xwork> 36UUt!}p
N;R I
A
S,vh
!yD$fY
pB'{_{8aA
/Suh&qw>
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 :N64FR#
xl ,(=L]
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。 W]I+Rlv)U
I6Ga'5bV
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 y&6 pc
2x!cblo
*9tRhRc
5+[ 3@
4WP@ F0@n3
我写的一个用于分页的类,用了泛型了,hoho
6)yi^v
)`K!XX$%
java代码: p(.z#o#
8 `}I]
tL]T_]z
package com.intokr.util; J*4T|#0
'$5Qdaj
import java.util.List; _K3;$2d|R
+%R{j|8#
/** [Gc9
3PA7q
* 用于分页的类<br> 6e%ZNw{#=
* 可以用于传递查询的结果也可以用于传送查询的参数<br> ?g4S51zpp
* }#2I/dn
* @version 0.01 I lZ$Jd
* @author cheng 6#kmV
*/ <&l@ ):a
public class Paginator<E> { 1!;4I@W(I)
privateint count = 0; // 总记录数 3|BB#;
privateint p = 1; // 页编号 )u1=, D
privateint num = 20; // 每页的记录数 AI]lG]q8
privateList<E> results = null; // 结果 a xz-H`oq4
6iS7Hao"
/** ,L\>mGw
* 结果总数 bMGXx>x
*/ t**MthnW
publicint getCount(){ R%6KxN)+@
return count; ]v#T9QQN
} 7A^L$TY
HjY! ]!4p
publicvoid setCount(int count){ pYh\l.@qf
this.count = count; y>0Gmr
} XA\wZV
|{
U% OlYP$g
/** 7n7UL0Oc1
* 本结果所在的页码,从1开始 4A)_D{(SH
* _Uhl4Mh
* @return Returns the pageNo. kV4,45r
*/ 0E#?H0<OeG
publicint getP(){ Va^(cnwa
return p; lT_dzO
} zT ")!Df>'
5ljEh -
/** ; jrmr`l=
* if(p<=0) p=1 Wa9yyc
* %v[KLMo'(
* @param p vw
:&c.zd
*/ ohi0_mBz
publicvoid setP(int p){ tNljv >vI
if(p <= 0) ZUS06#t}
p = 1; ne%(`XY{Q]
this.p = p; Gm=e;X;r
} 0P;\ :-&p
|OIU)53A-
/** av~kF
* 每页记录数量 V^_U=Ed@M
*/ lqvP
Dz
publicint getNum(){ .\8LL,zT
return num; e8{!Kjiz
} ;#=y5Q4
Mg&<W#$K
/** Nb)Mh
* if(num<1) num=1 WQMoAPfqL
*/ B^/(wHBp
publicvoid setNum(int num){ GjbOc
if(num < 1) rLA^ &P:
num = 1; o w;a7
this.num = num; 6u xF<
} DuIgFp
#v*3-) 8
/** ON"p^o>/_?
* 获得总页数 kNX8y--
*/ qyjVB/ko
publicint getPageNum(){ q siV
return(count - 1) / num + 1; a\KM^jrCD
} @_?Uowc8
jWso'K
/** q><wzCnRu~
* 获得本页的开始编号,为 (p-1)*num+1 (O/W`qo
*/ Ss:'HH4
publicint getStart(){ 1jd.tup
return(p - 1) * num + 1; _)6r@fZ.p
} Gn;^]8d
79B+8= K
/** Nx!7sE*b$1
* @return Returns the results. f/{ClP.
*/ *r ('A
publicList<E> getResults(){ rd,!-w5
return results; a..LbQQ
} [-^xw1:
lU`t~|>r+
public void setResults(List<E> results){ Fe2t[y:8h
this.results = results; 4^!%>V"d/
} 10tTV3`IM
ktM7L{Nz
public String toString(){ @B!gxW\C
StringBuilder buff = new StringBuilder zek>]l`!
Ob]J!.
(); &&C'\,ZK5
buff.append("{"); H%{k.#O
buff.append("count:").append(count); 7_J0[C!G
buff.append(",p:").append(p); 28j/K=0(
buff.append(",nump:").append(num); )ib$*dmUP
buff.append(",results:").append VdGpreRPC
!:v7SRUXb
(results); v3wq-
buff.append("}"); uW4.Q_O!H
return buff.toString(); K*M1$@5
} bQdu= s[
#P
{|7}jk
}
)!FheoR
PgsG*5WQ
PoLk{{l3