Servlet compile error why?
Hi!
All day I was trying to compile a java servlet, but I always get error message. My java file is the following: (PetiServlet.java)
import java.io.*;
import javax.servlet.*;
import javax.servlet.http.*;
public class PetiServlet extends HttpServlet {
When I try to compile (javac PetiServlet.java), get the following error message:
C:\j2sdk1.4.1_01\temp>javac PetiServl
PetiServlet.java:2: package javax.ser
import javax.servlet.*;
^
PetiServlet.java:3: package javax.ser
import javax.servlet.http.*;
^
PetiServlet.java:5: cannot resolve sy
symbol : class HttpServlet
location: class PetiServlet
public class PetiServlet extends Http
^
3 errors
Ok, I have installed the j2sdk1.4.1_01 , the jsdk2.0, the j2ee. I have the servlet.jar file in my classpath c:\j2sdk1.4.1_01\classpath
CLASSPATH="C:\JSDK2.0\lib\";c:\j2sdk1.4.1_01\classpath;
JAVA_HOME=c:\j2sdk1.4.1_01;
Its seems everything ok, but what's wrong?
Thank you! Peter
Try this,
javac -classpath C:\JSDK2.0\lib\;.;C:\j2sdk1.4.1_01\classpath\servlet.jar PetiServlet.java
The basic idea is, you need to add each jar file independently into classpath. Adding the folder into classpath is just not sufficient.
Sudha
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AIX,WLS 5.1 sp10,.........
Thu Jun 07 11:54:41 CDT 2001:<I> <ServletContext-dcms> Generated java
file: /usr/local/weblogic/test-weblogic/weblogic/myserver/dcms
web/app/tmp_war/jsp_servlet/_report/_walmart_95_prod_95_proof_95_report.java
Thu Jun 07 11:54:42 CDT 2001:<E> <ServletContext-dcms> Compilation of
/usr/local/weblogic/test-weblogic/weblogic/myserver/dcms_web/a
pp/_tmp_war/jsp_servlet/_report/_walmart_95_prod_95_proof_95_report.java
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java.io.IOException: Compiler failed
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/usr/java_dev2/jre/sh/../lib/rt.jar:/usr
/java_dev2/jre/sh/../lib/i18n.jar:/usr/java_dev2/jre/sh/../classes:./classes/boot:./eval/cloudscape/lib/cloudscape.jar:./anderson_co
mmon/3rd_party_jars/jt400.jar:/usr/lpp/db2_07_01/java/db2java.zip::./lib/weblogic510sp8boot.jar:./license:./classes:./lib/weblogicau
x.jar:./myserver/serverclasses:./anderson_common/3rd_party_jars/jt400.jar:/usr/lpp/db2_07_01/java/db2java.zip::./classes/dcms/com.ib
m.mq.iiop.jar:./classes/dcms/com.ibm.mq.jar:./classes/dcms/com.ibm.mqbind.jar:./classes/dcms/com.ibm.mqjms.jar:./classes/dcms/com_au
th.jar:./classes/dcms/com_auth_server.jar:./classes/dcms/com_io.jar:./classes/dcms/com_jms.jar:./classes/dcms/com_jndi.jar:./classes
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dcms_common_server.jar:./classes/dcms/dcms_dl_render_server.jar:./classes/dcms/dcms_finalresting_server.jar:./classes/dcms/dcms_fulf
illment.jar:./classes/dcms/dcms_fulfillment_server.jar:./classes/dcms/dcms_fulfillment_walmart_server.jar:./classes/dcms/dcms_lookup
_server.jar:./classes/dcms/dcms_media_server.jar:./classes/dcms/dcms_order.jar:./classes/dcms/dcms_order_server.jar:./classes/dcms/d
cms_order_session.jar:./classes/dcms/dcms_product.jar:./classes/dcms/dcms_product_server.jar:./classes/dcms/dcms_render_client.jar:.
/classes/dcms/dcms_render_server.jar:./classes/dcms/dcms_talent_server.jar:./classes/dcms/dcms_talent.jar:./classes/dcms/dcms_walmar
t.jar:./classes/dcms/dcms_walmart_server.jar:./classes/dcms/dcms_jms.jar:./classes/dcms/xreport_pro.jar:./classes/dcms/xtools.jar:./
classes/dcms/jms.jar:./classes/dcms/dcms_sql.jar:./classes/dcms/dcms_product_sql.jar::/usr/local/weblogic/test-weblogic/weblogic/mys
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gic/test-weblogic/weblogic/myserver/tmp_deployments/ejbjar-4970.jar:/usr/local/weblogic/test-weblogic/weblogic/myserver/tmp_deployme
nts/ejbjar-4969.jar:/usr/local/weblogic/test-weblogic/weblogic/myserver/tmp_deployments/ejbjar-4968.jar:/usr/local/weblogic/test-web
logic/weblogic/myserver/tmp_deployments/ejbjar-4967.jar:/usr/local/weblogic/test-weblogic/weblogic/myserver/tmp_deployments/ejbjar-4
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ic/myserver/tmp_deployments/ejbjar-4964.jar:/usr/local/weblogic/test-weblogic/weblogic/myserver/tmp_deployments/ejbjar-4963.jar:/usr
/local/weblogic/test-weblogic/weblogic/myserver/tmp_deployments/ejbjar-4962.jar:/usr/local/weblogic/test-weblogic/weblogic/myserver/
tmp_deployments/ejbjar-4961.jar:/usr/local/weblogic/test-weblogic/weblogic/myserver/tmp_deployments/ejbjar-4960.jar:/usr/local/weblo
gic/test-weblogic/weblogic/myserver/tmp_deployments/ejbjar-4959.jar:/usr/local/weblogic/test-weblogic/weblogic/myserver/tmp_deployme
nts/ejbjar-4958.jar:/usr/local/weblogic/test-weblogic/weblogic/myserver/tmp_deployments/ejbjar-4957.jar:/usr/local/weblogic/test-web
logic/weblogic/myserver/tmp_deployments/ejbjar-4956.jar:/usr/local/weblogic/test-weblogic/weblogic/myserver/tmp_deployments/ejbjar-4
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ic/myserver/tmp_deployments/ejbjar-4953.jar:/usr/local/weblogic/test-weblogic/weblogic/myserver/tmp_deployments/ejbjar-4952.jar:/usr
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r/dcms_web/app/WEB-INF/classes:/usr/local/test-weblogic/weblogic/myserver/dcms_web/app/WEB-INF/classes:/usr/local/weblogic/test-webl
ogic/weblogic/./myserver/dcms_web/app/_tmp_war:/usr/local/weblogic/test-weblogic/weblogic/myserver/dcms_web/app/_tmp_war,
-d, /usr/l
ocal/weblogic/test-weblogic/weblogic/myserver/dcms_web/app/_tmp_war,
/usr/local/weblogic/test-weblogic/weblogic/myserver/dcms_web/ap
p/_tmp_war/jsp_servlet/_report/_walmart_95_prod_95_proof_95_report.java])
at
weblogic.utils.compiler.CompilerInvoker.compileMaybeExit(CompilerInvoker.java:396)
at
weblogic.utils.compiler.CompilerInvoker.compile(CompilerInvoker.java:202)
at weblogic.servlet.jsp.JspStub.compilePage(JspStub.java:284)
at weblogic.servlet.jsp.JspStub.prepareServlet(JspStub.java:174)
at
weblogic.servlet.internal.ServletStubImpl.getServlet(ServletStubImpl.java:164)
at
weblogic.servlet.internal.ServletStubImpl.invokeServlet(ServletStubImpl.java:99)
at
weblogic.servlet.internal.RequestDispatcherImpl.forward(RequestDispatcherImpl.java(Compiled
Code))
at com.web.CommonWebUtils.forward(CommonWebUtils.java(Compiled
Code))
at com.web.PageNavServlet.service(PageNavServlet.java:76)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:865)
at
weblogic.servlet.internal.ServletStubImpl.invokeServlet(ServletStubImpl.java:105)
at
weblogic.servlet.internal.ServletContextImpl.invokeServlet(ServletContextImpl.java:742)
at
weblogic.servlet.internal.ServletContextImpl.invokeServlet(ServletContextImpl.java:686)
at
weblogic.servlet.internal.ServletContextManager.invokeServlet(ServletContextManager.java:247)
at
weblogic.socket.MuxableSocketHTTP.invokeServlet(MuxableSocketHTTP.java:361)
at
weblogic.socket.MuxableSocketHTTP.execute(MuxableSocketHTTP.java:261)
at weblogic.kernel.ExecuteThread.run(ExecuteThread.java:120)
----------------------Caught exception while forwarding to page
/report/walmart_prod_proof_report.jsp------------------------
----------------------Exception java.io.IOException: Compiler failed
executable.exec([Ljava.lang.String;[javac, -classpath, /usr/jav
a_dev2/jre/sh/../lib/rt.jar:/usr/java_dev2/jre/sh/../lib/i18n.jar:/usr/java_dev2/jre/sh/../classes:./classes/boot:./eval/cloudscape/
lib/cloudscape.jar:./anderson_common/3rd_party_jars/jt400.jar:/usr/lpp/db2_07_01/java/db2java.zip::./lib/weblogic510sp8boot.jar:./li
cense:./classes:./lib/weblogicaux.jar:./myserver/serverclasses:./anderson_common/3rd_party_jars/jt400.jar:/usr/lpp/db2_07_01/java/db
2java.zip::./classes/dcms/com.ibm.mq.iiop.jar:./classes/dcms/com.ibm.mq.jar:./classes/dcms/com.ibm.mqbind.jar:./classes/dcms/com.ibm
.mqjms.jar:./classes/dcms/com_auth.jar:./classes/dcms/com_auth_server.jar:./classes/dcms/com_io.jar:./classes/dcms/com_jms.jar:./cla
sses/dcms/com_jndi.jar:./classes/dcms/com_system.jar:./classes/dcms/com_system_server.jar:./classes/dcms/com_util.jar:./classes/dcms
/dcms_common.jar:./classes/dcms/dcms_common_server.jar:./classes/dcms/dcms_dl_render_server.jar:./classes/dcms/dcms_finalresting_ser
ver.jar:./classes/dcms/dcms_fulfillment.jar:./classes/dcms/dcms_fulfillment_server.jar:./classes/dcms/dcms_fulfillment_walmart_serve
r.jar:./classes/dcms/dcms_lookup_server.jar:./classes/dcms/dcms_med
rder_server.jar:./classes/dcms/dcms_order_session.jar:./classes/dcm
es/dcms/dcms_render_client.jar:./classes/dcms/dcms_render_server.jar:./classes/dcms/dcms_talent_server.jar:./classes/dcms/dcms_talen
t.jar:./classes/dcms/dcms_walmart.jar:./classes/dcms/dcms_walmart_server.jar:./classes/dcms/dcms_jms.jar:./classes/dcms/xreport_pro.
jar:./classes/dcms/xtools.jar:./classes/dcms/jms.jar:./classes/dcms/dcms_sql.jar:./classes/dcms/dcms_product_sql.jar::/usr/local/web
logic/test-weblogic/weblogic/myserver/tmp_deployments/ejbjar-4971.jar:/usr/local/weblogic/test-weblogic/weblogic/lib/persistence/Web
Logic_RDBMS.jar:/usr/local/weblogic/test-weblogic/weblogic/myserver/tmp_deployments/ejbjar-4970.jar:/usr/local/weblogic/test-weblogi
c/weblogic/myserver/tmp_deployments/ejbjar-4969.jar:/usr/local/weblogic/test-weblogic/weblogic/myserver/tmp_deployments/ejbjar-4968.
jar:/usr/local/weblogic/test-weblogic/weblogic/myserver/tmp_deployments/ejbjar-4967.jar:/usr/local/weblogic/test-weblogic/weblogic/m
yserver/tmp_deployments/ejbjar-4966.jar:/usr/local/weblogic/test-weblogic/weblogic/myserver/tmp_deployments/ejbjar-4965.jar:/usr/loc
al/weblogic/test-weblogic/weblogic/myserver/tmp_deployments/ejbjar-4964.jar:/usr/local/weblogic/test-weblogic/weblogic/myserver/tmp_
deployments/ejbjar-4963.jar:/usr/local/weblogic/test-weblogic/weblogic/myserver/tmp_deployments/ejbjar-4962.jar:/usr/local/weblogic/
test-weblogic/weblogic/myserver/tmp_deployments/ejbjar-4961.jar:/usr/local/weblogic/test-weblogic/weblogic/myserver/tmp_deployments/
ejbjar-4960.jar:/usr/local/weblogic/test-weblogic/weblogic/myserver/tmp_deployments/ejbjar-4959.jar:/usr/local/weblogic/test-weblogi
c/weblogic/myserver/tmp_deployments/ejbjar-4958.jar:/usr/local/weblogic/test-weblogic/weblogic/myserver/tmp_deployments/ejbjar-4957.
jar:/usr/local/weblogic/test-weblogic/weblogic/myserver/tmp_deployments/ejbjar-4956.jar:/usr/local/weblogic/test-weblogic/weblogic/m
yserver/tmp_deployments/ejbjar-4955.jar:/usr/local/weblogic/test-weblogic/weblogic/myserver/tmp_deployments/ejbjar-4954.jar:/usr/loc
al/weblogic/test-weblogic/weblogic/myserver/tmp_deployments/ejbjar-4953.jar:/usr/local/weblogic/test-weblogic/weblogic/myserver/tmp_
deployments/ejbjar-4952.jar:/usr/local/weblogic/test-weblogic/weblogic/myserver/tmp_deployments/ejbjar-4951.jar:/usr/local/weblogic/
test-weblogic/weblogic/./myserver/dcms_web/app/WEB-INF/classes:/usr/local/test-weblogic/weblogic/myserver/dcms_web/app/WEB-INF/class
es:/usr/local/weblogic/test-weblogic/weblogic/./myserver/dcms_web/app/_tmp_war:/usr/local/weblogic/test-weblogic/weblogic/myserver/d
cms_web/app/_tmp_war, -d,
/usr/local/weblogic/test-weblogic/weblogic/myserver/dcms_web/app/_tmp_war,
/usr/local/weblogic/test-weblog
ic/weblogic/myserver/dcms_web/app/_tmp_war/jsp_servlet/_report/_walmart_95_prod_95_proof_95_report.java])------------------------
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}strings are immutable... we can not alter it... so
why the below does not create compile error ? First of all, Strings are immuatable because the String class is coded that way - there willnever be a compiler error to stop you from altering a String's value (which is actually possible via reflection). This is similar to you writing your own class that has a private field and not providing any methods that can alter the field's value. Your new class would be considered immutable in the same way that Strings are considered immutable, and nobody can even attempt (except reflectively), to "alter" an instance of it, so there will never be a compiler error that is due to such an attempt.
it is an attempt to alter the string.No it isn't. The following is a quote from the Javadoc for String.concat:
"If the length of the argument string is 0, then this String object is returned. Otherwise, a new String object is created, representing a character sequence that is the concatenation of the character sequence represented by this String object and the character sequence represented by the argument string." -
Class javax.servlet.jsp.PageContext compilation error
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simeple code here
class IncompInterfaceTest {
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ClassB b = new ClassB();
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class ClassB{}
javac issues "ClassCastException" on runtime rather than compile
error.
as i know incompatible type casting may be caught at runtime and
compiler shows the error.
but why compiler doesn't do it's job for interfaces? it's just so
clear to be compile error to me.
ps. in a case ClassB is final class, compiler issues a error.
(a thread I started in google groups)
http://groups.google.co.kr/group/comp.lang.java.programmer/browse_thread/thread/c9c12a8864672436?hl=ko#sun9h0st wrote:
thanks for reply.
I think i might know something wrong about class, object concept, so I wish you tell me more about it.
As I though the code below means
ClassB b = new ClassC();'b' can be an Object of ClassB as a subclass of ClassC.
'b' IS an Object of ClassC.b is not an object.
b is a variable that can point to an instance of ClassB or to an instance of any subclass of ClassB.
>
so
b instanceof ClassB == true // as it can be
b instanceof ClassC == true // as it is
If b is not null, the first line will always be true.
If b points to a ClassC or a subclass, the second one will be true.
It means actual Object(something behind 'b' pointing, i don't know what i call it) is from ClassC to me. (somewhat like c pointer,
'b' is a bowl that called Object and actuall instance is refered by 'b')No idea what you're saying here.
if b IS an Object of ClassB
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B b1 = new B();
B b2 = new C();
b1 instanceof B // true
b1 instanceof C // false
b2 instanceof B // true
b2 instanceof C // true
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import java.util.Collection;
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Map<Integer, String> temp = new HashMap<Integer, String>();
temp.put(new Integer(1), "cat");
temp.put(new Integer(2), "rat");
Collection coll = temp.values();
String[] arr = (String[]) coll.toArray();
System.out.println(arr.length);
} Thanks,
Harish SrinivasanInfiniti wrote:
Why don't we get a compilation error but get a runtime error while explicit casting of Object[] into a String[]?
import java.util.Collection;
import java.util.HashMap;
import java.util.Map;
public class SampleMap {
public static void main(String[] args) {
Map<Integer, String> temp = new HashMap<Integer, String>();
temp.put(new Integer(1), "cat");
temp.put(new Integer(2), "rat");
Collection coll = temp.values();
String[] arr = (String[]) coll.toArray();
System.out.println(arr.length);
} Thanks,
Harish SrinivasanAn explicit cast's job is to tell the compiler that even though it cannot guarantee that the conversion will work, allow the code anyway and let the runtime handle an error if it occurs. -
Why no compiler error is generated ?
When I try to store value 0xff in a byte variale with the statement :
byte b=0xff;
a compiler error is generated
but when I try to store the value 0xffffffff in b no complier error occurs.
The quetion is if the compiler can truncate bits in case of value 0xffffffff then why not in case of 0xff.sharmaneha wrote:
but the question is why does not the compiler truncate the value for 0xff?That's 255, which is more than 127, which is the max value for a byte (they can be between -128 and 127) -
Why compilation error--when trying to access the table from itcsi schema
Hi,
when querying the table from itcsi.app iam able to see the data but used in proc saying invalid table name. Whats the problem
when declared p_app_i_old app.app_i%type----It is throwing pls-00201 error
1 Create or replace procedure Test_insert(p_app_i_old integer,
2 p_app_i_new integer,
3 p_APP_ISAC_CPT_I varchar2)
4 is
5 cursor c1 is
6 select distinct table_name,owner
7 from all_tab_columns
8 where owner = 'ITCSI' and column_name='APP_I';
9 t_tablename varchar2(25);
10 t_string varchar2(300);
11 t_num number;
12 Begin
13 For c2 in c1 loop
14 t_num := 0;
15 t_string := 'SELECT count(*) FROM ' || c2.owner ||'.'||c2.table_name||' WHERE APP_I = '||p_
16 execute immediate t_string into t_num;
17 if t_num > 0 then
18 -- dbms_output.put_line('The table name is '||c1_rec.table_name);
19 if c2.Table_name = 'APP' Then
20 INSERT INTO itcsi.App
21 SELECT p_app_i_new,
22 app_acrnym_c,
23 app_x,
24 app_desc_t,
25 app_ipads_t,
26 app_prdcn_stat_t,
27 app_prdcn_stat_d,
28 app_isd_tier_c,
29 app_bus_cont_c,
30 app_extnl_cstm_c,
31 app-ecrpt_lvl_c,
32 app_isac_cpt_i,
33 dsw_gpn_i,
34 ed_cntnt_srce_t,
35 usr_upd_uunm_i,
36 ed_upd_m
37 FROM itcsi.APP
38 WHERE app_i = p_app_i_old;
39 elsif c2.Table_name = 'APP_CETRN' Then
40 Insert into itcsi.APP_CETRN
41 select p_app_i_new,
42 app_cetrn_i,
43 app-curr_cmplnc_t,
44 app_rqr_cmplnc_t,
45 dsw_gpn_i,
46 ed_cntnt_srce_t,
47 usr_upd_uunm_i,
48 ed_upd_m
49 FROM itcsi.APP_CETRN
50 WHERE app_i = p_app_i_old;
51 elsif c2.Table_name = 'APP_GPC' Then
52 Insert into itcsi.APP_GPC
53 select p_app_i_new,
54 gpc_dpnt_x,
55 gpc_elemy_x,
56 pro_i,
57 dsw_gpn_i,
58 ed_cntnt_srce_t,
59 usr_usr_upd_uunm
60 FROM itcsi.APP_GPC
61 WHERE app_i = p_app_i_old;
62 End if;
63 End if;
64 End loop;
65 --Commit;
66* End;
SQL> /
Warning: Procedure created with compilation errors.
SQL> show errors
Errors for PROCEDURE TEST_INSERT:
LINE/COL ERROR
20/2 PL/SQL: SQL Statement ignored
37/23 PL/SQL: ORA-00942: table or view does not exist
40/2 PL/SQL: SQL Statement ignored
Thankshow do i check the grant?
if am in my own schema,how do i connect to itcsi
schema?if you are using a schema other than the ITCSI schema, you need to login as ITCSI. or if you have dba user account you can grant a privilege of
GRANT ALL on ITCSI.APPS to <other SCHEMA>; -
Why does plsql give compilation error for select statement?
When I run following plsql program, it gives compilation error. Could somebody please point me out what could be wrong here? I am running it from system user.
create or replace procedure drop_user_proc (iname in varchar2) is
uname varchar2(100);
begin
select username into uname from dba_users where username = upper(iname);
end drop_user_proc;
select username from dba_users where username = upper('newuser');
When I run it, I get following error. dba_users is there that is the reason it works outside plsql block, but it doesn't from inside block.
SQL> @t4
Warning: Procedure created with compilation errors.
USERNAME
NEWUSER
SQL> show err
Errors for PROCEDURE DROP_USER_PROC:
LINE/COL ERROR
4/3 PL/SQL: SQL Statement ignored
4/35 PL/SQL: ORA-00942: table or view does not existRole based grants are not available within the stored procedures.
Only explicit grants are recognized when compiling stored code.
You need to grant select on that table to the user where you are creating this procedure.
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