500 Invalid method signature

Hi,
Can somebody help me out?
Getting the following error in the code:
500 Invalid method signature: t;)Ljava/lang/Object;
Invalid method signature: t;)Ljava/lang/Object;
Don't have any clue to fix this issue. Please help me.
Coldfusion version : 6
database : sql server.
Thanks,
Satheesh.

See how the above method is self explaining. Yes, returning an array is more self explanatory. Are you defensively copying the array?
For classes that are to be re-used often by other developers would it be better to use arrays because they are more obvious? It depends. Yes its more obvious but if folks are going to stick the array contents into a Collection then returning a Collection is nice, too.
How do other people deal with this or do you just not worry about it and leave it up to the comments to explain?Thats what javadoc is for. i.e. @return a List of EmailTo objects
In jdk1.5 templates will help with this a bit.
One of the most painful bugs you will encounter is when you don't make defensive copies of objects and another class mutates an internal data structure. Of course, defensive copies waste object references and in some cases, can really cause a slow down. You can always provide access via ye old getNumberOfFollowUpEmails/getFollowUpEmail(int i)
Ian

Similar Messages

  • Web Service Security with SAML - Invalid XML signature

    Hello together,
    we want to build a scenario where we want to use Web Service Security  with SAML.
    The scenario will be
    WS Client (Java Application) -> WS Adapter -> Integration Engine ->  WS Adapter-> CRM (Web AS ABAP 7.01 SP 3)
    SAP PI release is 7.11 (SP Level 4)
    We want to use the SAML Authentification from WS Client to PI and from PI to Web AS ABAP.
    The SAML authentifications between the WS Client and PI works when there is no SAML auth between PI and CRM.
    But we get following error at calling the CRM system when we want to communicate with SAML:
      <E_TEXT>CX_WS_SECURITY_FAULT:Invalid XML signature</E_TEXT>
    Has somebody an idea of the possible reason for the error.
    Thanks in advance
    Stefan

    Error Messages in the Trace/Log Viewer:
    CX_WS_SECURITY_FAULT : Invalid XML signature | program: CL_ST_CRYPTO==================CP include: CL_ST_CRYPTO==================CM00G line: 48
    A SOAP Runtime Core Exception occurred in method CL_ST_CRYPTO==================CM00G of class CL_ST_CRYPTO==================CP at position id 48  with internal error id 1001  and error text CX_WS_SECURITY_FAULT:Invalid XML signature (fault location is 1  ).
    Invalid XML signature

  • Java.lang.SecurityException: invalid SHA1 signature file digest for com/cry

    While running AVK I've got following error reported on 3d party code we are using. Is there anything that I can do to resolve this issue?
    Thank you in advance,
    Irena
         Error Name : com.sun.enterprise.tools.verifier.tests.web.WebArchiveClassesLoadable
         Error Description : java.lang.SecurityException: invalid SHA1 signature file digest for com/crystaldecisions/MetafileRenderer/DeviceContext$GDIState.class
         at sun.security.util.SignatureFileVerifier.verifySection(SignatureFileVerifier.java:390)
         at sun.security.util.SignatureFileVerifier.process0(SignatureFileVerifier.java:241)
         at sun.security.util.SignatureFileVerifier.process(SignatureFileVerifier.java:191)
         at java.util.jar.JarVerifier.processEntry(JarVerifier.java:235)
         at java.util.jar.JarVerifier.update(JarVerifier.java:190)
         at java.util.jar.JarFile.initializeVerifier(JarFile.java:304)
         at java.util.jar.JarFile.getInputStream(JarFile.java:366)
         at sun.net.www.protocol.jar.JarURLConnection.getInputStream(JarURLConnection.java:119)
         at java.net.URL.openStream(URL.java:913)
         at java.lang.ClassLoader.getResourceAsStream(ClassLoader.java:997)
         at com.sun.enterprise.tools.verifier.apiscan.classfile.BCELClassFileLoader.load(BCELClassFileLoader.java:69)
         at com.sun.enterprise.tools.verifier.apiscan.classfile.ClosureCompilerImpl.buildClosure(ClosureCompilerImpl.java:170)
         at com.sun.enterprise.tools.verifier.apiscan.classfile.ClosureCompilerImpl.buildClosure(ClosureCompilerImpl.java:176)
         at com.sun.enterprise.tools.verifier.apiscan.classfile.ClosureCompilerImpl.buildClosure(ClosureCompilerImpl.java:176)
         at com.sun.enterprise.tools.verifier.apiscan.classfile.ClosureCompilerImpl.buildClosure(ClosureCompilerImpl.java:176)
         at com.sun.enterprise.tools.verifier.apiscan.classfile.ClosureCompilerImpl.buildClosure(ClosureCompilerImpl.java:133)
         at com.sun.enterprise.tools.verifier.tests.web.WebArchiveClassesLoadable.check(WebArchiveClassesLoadable.java:53)
         at com.sun.enterprise.tools.verifier.tests.web.WebTest.check(WebTest.java:46)
         at com.sun.enterprise.tools.verifier.CheckMgr.check(CheckMgr.java:76)
         at com.sun.enterprise.tools.verifier.web.WebCheckMgrImpl.check(WebCheckMgrImpl.java:32)
         at com.sun.enterprise.tools.verifier.BaseVerifier.verify(BaseVerifier.java:86)
         at com.sun.enterprise.tools.verifier.web.WebVerifier.verify(WebVerifier.java:43)
         at com.sun.enterprise.tools.verifier.VerificationHandler.runVerifier(VerificationHandler.java:136)
         at com.sun.enterprise.tools.verifier.VerificationHandler.verifyArchive(VerificationHandler.java:82)
         at com.sun.enterprise.tools.verifier.Verifier.verify(Verifier.java:75)
         at com.sun.enterprise.tools.verifier.Verifier.main(Verifier.java:53)

    could you solve the problem? while I'm connecting to sql server , I get the same error. in fact, i can connect to server through eclipse ide but when i export my application into a jar and try connecting to server through the jar, this problem occurs.
    I thought, you can give me a idea. I don't know where I should start. please, help me..
    Exception in thread "main" java.lang.SecurityException: invalid SHA1 signature f
    ile digest for com/microsoft/sqlserver/jdbc/SQLServerException.class
    at sun.security.util.SignatureFileVerifier.verifySection(Unknown Source)
    at sun.security.util.SignatureFileVerifier.processImpl(Unknown Source)
    at sun.security.util.SignatureFileVerifier.process(Unknown Source)
    at java.util.jar.JarVerifier.processEntry(Unknown Source)
    at java.util.jar.JarVerifier.update(Unknown Source)
    at java.util.jar.JarFile.initializeVerifier(Unknown Source)
    at java.util.jar.JarFile.getInputStream(Unknown Source)
    at sun.misc.URLClassPath$JarLoader$2.getInputStream(Unknown Source)
    at sun.misc.Resource.cachedInputStream(Unknown Source)
    at sun.misc.Resource.getByteBuffer(Unknown Source)
    at java.net.URLClassLoader.defineClass(Unknown Source)
    at java.net.URLClassLoader.access$000(Unknown Source)
    at java.net.URLClassLoader$1.run(Unknown Source)
    at java.security.AccessController.doPrivileged(Native Method)
    at java.net.URLClassLoader.findClass(Unknown Source)
    at java.lang.ClassLoader.loadClass(Unknown Source)
    at sun.misc.Launcher$AppClassLoader.loadClass(Unknown Source)
    at java.lang.ClassLoader.loadClass(Unknown Source)
    at java.lang.ClassLoader.loadClassInternal(Unknown Source)

  • Invalid method "Save As" from Excel application object

    I have Windows 2000 and Excel 2002 installed on my machine.
    I down loaded "renamed Excel 2000 workbook.vi" from NI website. Relinked ref num to Excel application object but get the error of invalid method (Save As). Tried to relink invoke node to Save As by selecting method from drop down menu. However this method is not on the list. Tried other excel objects but can not find "Save As" method. Has this been removed/moved?

    I was able to correct the error by relinking the Workbooks->Open to Open. This changes the subsequent Invoke Node from IAppEvents to _Workbook. There you will find the Save As method.
    Michael
    www.abcdefirm.com
    Michael Munroe, ABCDEF
    Certified LabVIEW Developer, MCP
    Find and fix bad VI Properties with Property Inspector

  • No Method Signature - initQuery error after VO Substitution

    Hi All,
    I have done a VO Substitution for "NewBankAccountVOImpl". Below is the exact Requirement,
    iReceivables -> Query for a given Customer -> Go to accounts Tab -> Try to Pay off an invoice -> You get an option choose Payment Method as "New Bank Account" ->
    Now there are three field Routing Number, Account Number and Account Holder
    I need to restrict Account Number to minimum three characters. In 11.5.10 Oracle do not have this validation.
    So I checked out the place where the Routing Number and Account Number Validation happen i.e "NewBankAccountVOImpl" and extended the same to custom VOImpl and copied all the standard code to my custom code as below,
    package mercury.oracle.apps.ar.irec.accountDetails.pay.server;
    import oracle.apps.ar.irec.accountDetails.pay.server.NewBankAccountVOImpl;
    import oracle.apps.ar.irec.accountDetails.pay.server.NewBankAccountVORowImpl;
    import java.sql.Types;
    import java.lang.String;
    import oracle.apps.ar.irec.accountDetails.pay.utilities.PaymentUtilities;
    import oracle.apps.ar.irec.framework.IROAViewObjectImpl;
    import oracle.apps.fnd.common.VersionInfo;
    import oracle.apps.fnd.framework.OAException;
    import oracle.apps.fnd.framework.server.*;
    import oracle.apps.fnd.framework.webui.OAWebBeanConstants;
    import oracle.jbo.RowIterator;
    import oracle.jbo.RowSetIterator;
    import oracle.jbo.domain.Number;
    import oracle.jbo.server.DBTransaction;
    import oracle.jdbc.driver.OracleCallableStatement;
    import oracle.jdbc.driver.OraclePreparedStatement;
    // --- File generated by Oracle Business Components for Java.
    // --------------- Modification History --------------------------
    // Date Created By Description
    // 04/01/2011 Veerendra K Account Number Validation to raise
    // error if Account Number entered is
    // less than 3 Digits
    public class MMARNewBankAccountVOImpl extends NewBankAccountVOImpl
    * This is the default constructor (do not remove)
    public MMARNewBankAccountVOImpl()
    public void initQuery()
    if(!isExecuted())
    executeQuery();
    reset();
    // Wrapper Method to validate Routing Number and Account Number
    public void validateNewBankAccount()
    OAApplicationModuleImpl oaapplicationmoduleimpl = (OAApplicationModuleImpl)getApplicationModule();
    RowSetIterator rowsetiterator = createRowSetIterator("iter");
    rowsetiterator.reset();
    NewBankAccountVORowImpl newbankaccountvorowimpl = (NewBankAccountVORowImpl)rowsetiterator.next();
    rowsetiterator.closeRowSetIterator();
    OAException oaexception = null;
    //object obj = null;
    int i = validateRoutingNumber(newbankaccountvorowimpl.getStrippedRoutingNumber());
    if(i == 0)
    OAException oaexception1 = new OAException("AR", "ARI_INVALID_ROUTING_NUMBER");
    if(oaexception == null)
    oaexception = oaexception1;
    else
    oaexception.setNextException(oaexception1);
    } else
    if(i == 2)
    OAException oaexception2 = new OAException("AR", "ARI_CREATE_BANK_ACCOUNT");
    if(oaexception == null)
    oaexception = oaexception2;
    else
    oaexception.setNextException(oaexception2);
    // Added by VEERENDRA KODALLI to limit addition of New Bank Account with Minimum 3 Digits
    if(validateBankAccountNumber(newbankaccountvorowimpl.getStrippedBankAccountNumber()))
    // Define Exception with FND Message MMARI_INVALID_BA_NUMBER
    OAException oaexception4 = new OAException("AR", "MMARI_INVALID_BA_NUMBER");
    if(oaexception == null)
    oaexception = oaexception4;
    else
    oaexception.setNextException(oaexception4);
    // Method to Validate if Entered Account Number and Routing Number Combination already exist
    if(validateDuplicateBankAccountNumber(newbankaccountvorowimpl.getStrippedBankAccountNumber(), newbankaccountvorowimpl.getStrippedRoutingNumber(), newbankaccountvorowimpl.getAccountHolderName()))
    OAException oaexception3 = new OAException("AR", "ARI_DUPLICATE_BA_NUMBER");
    if(oaexception == null)
    oaexception = oaexception3;
    else
    oaexception.setNextException(oaexception3);
    if(oaexception != null)
    oaexception.setApplicationModule(oaapplicationmoduleimpl);
    throw oaexception;
    } else
    return;
    // Method to Validate Routing Number
    public int validateRoutingNumber(String s)
    boolean flag = PaymentUtilities.checkDigits(s);
    if(!flag)
    return 0;
    OAApplicationModuleImpl oaapplicationmoduleimpl = (OAApplicationModuleImpl)getApplicationModule();
    OADBTransaction oadbtransaction = (OADBTransaction)oaapplicationmoduleimpl.getDBTransaction();
    if(oadbtransaction.isLoggingEnabled(2))
    oadbtransaction.writeDiagnostics(this, "Start validateRoutingNumber", 2);
    String s1 = "BEGIN :1 := ARP_BANK_DIRECTORY.is_routing_number_valid(:2,:3); END;";
    OracleCallableStatement oraclecallablestatement = (OracleCallableStatement)oadbtransaction.createCallableStatement(s1, 1);
    int i = 0;
    try
    oraclecallablestatement.registerOutParameter(1, -5, 38, 38);
    oraclecallablestatement.setString(2, s);
    oraclecallablestatement.setString(3, "ABA");
    oraclecallablestatement.execute();
    i = oraclecallablestatement.getInt(1);
    catch(Exception exception1)
    exception1.printStackTrace();
    throw OAException.wrapperException(exception1);
    finally
    try
    oraclecallablestatement.close();
    catch(Exception exception2)
    throw OAException.wrapperException(exception2);
    // Debug Message
    if(oadbtransaction.isLoggingEnabled(2))
    oadbtransaction.writeDiagnostics(this, "End validateRoutingNumber", 2);
    return i;
    // Method to Validate Duplicate Account Number
    public boolean validateDuplicateBankAccountNumber(String s, String s1, String s2)
    OAApplicationModuleImpl oaapplicationmoduleimpl = (OAApplicationModuleImpl)getApplicationModule();
    OADBTransaction oadbtransaction = (OADBTransaction)oaapplicationmoduleimpl.getDBTransaction();
    if(oadbtransaction.isLoggingEnabled(2))
    // Debug Message
    oadbtransaction.writeDiagnostics(this, "Start validateDuplicateBankAccountNumber", 2);
    String s3 = "BEGIN :1 := AR_IREC_PAYMENTS.is_bank_account_duplicate(:2,:3,:4); END;";
    OracleCallableStatement oraclecallablestatement = (OracleCallableStatement)oadbtransaction.createCallableStatement(s3, 1);
    boolean flag = true;
    try
    oraclecallablestatement.registerOutParameter(1, -5, 38, 38);
    oraclecallablestatement.setString(2, s);
    oraclecallablestatement.setString(3, s1);
    oraclecallablestatement.setString(4, s2);
    oraclecallablestatement.execute();
    Number number = new Number(oraclecallablestatement.getLong(1));
    if(number.equals(new Number("0")))
    flag = false;
    else
    flag = true;
    catch(Exception exception1)
    exception1.printStackTrace();
    throw OAException.wrapperException(exception1);
    finally
    try
    oraclecallablestatement.close();
    catch(Exception exception2)
    throw OAException.wrapperException(exception2);
    // Debug Message
    if(oadbtransaction.isLoggingEnabled(2))
    oadbtransaction.writeDiagnostics(this, "End validateDuplicateBankAccountNumber", 2);
    return flag;
    public boolean validateBankAccountNumber(String s)
    OAApplicationModuleImpl oaapplicationmoduleimpl = (OAApplicationModuleImpl)getApplicationModule();
    OADBTransaction oadbtransaction = (OADBTransaction)oaapplicationmoduleimpl.getDBTransaction();
    // Debug Message
    if(oadbtransaction.isLoggingEnabled(2))
    oadbtransaction.writeDiagnostics(this, "Start validateBankAccountNumber", 2);
    boolean flag = true;
    try
    // Check if the Account Number Length is less than 3 Digits
    if(s.length() < 3)
    flag = true;
    // Debug Message
    if(oadbtransaction.isLoggingEnabled(2))
    oadbtransaction.writeDiagnostics(this, "Account Number Less than 3 Digits!", 2);
    else
    // Debug Message
    if(oadbtransaction.isLoggingEnabled(2))
    oadbtransaction.writeDiagnostics(this, "Account Number greater than 3 Digits!", 2);
    flag = false;
    //return PaymentUtilities.checkDigits(s);
    catch (Exception exception4)
    //if(oadbtransaction.isLoggingEnabled(2))
    //oadbtransaction.writeDiagnostics(this, "Entered Catch", 2);
    throw OAException.wrapperException(exception4);
    if(oadbtransaction.isLoggingEnabled(2))
    // Debug Message
    oadbtransaction.writeDiagnostics(this, "End validateBankAccountNumber", 2);
    return flag;
    public static final String RCS_ID = "$Header: NewBankAccountVOImpl.java 115.8 2008/07/21 13:49:37 nkanchan noship $";
    public static final boolean RCS_ID_RECORDED = VersionInfo.recordClassVersion("$Header: NewBankAccountVOImpl.java 115.8 2008/07/21 13:49:37 nkanchan noship $", "oracle.apps.ar.irec.accountDetails.pay.server");
    I did compile the Java File and also the JPX import. It was all successful. I tested the code and it worked as expected. Now I see an exception on the page when I click the Pay button stating "No Method Signature No Method Signature - initQuery".
    The error do not come when I take out my substitution. Any one know what might be the reason for above issue. I have no idea why all of a sudden it stopped working and checked all standard filles but none got changed.
    Any pointers towards to resolve the same would be appreciable.
    Thanks in Advance,
    Veerendra

    Uma,
    try to delete all class files, recompile and run! Also, check if any CO is not extended other than from OAControllerImpl, although it would not be generally.
    --Mukul                                                                                                                                                                                                                                                                                                                                                                                                                                                               

  • Problems deploying application with updated method signatures on WLS8.1

    Hi,
    I have an jar file under applications which I have deployed fine on WLS 8.1 in the past. I changed the method signature on one of the EJB classes in the jar. One of the parameters now takes a different Java class type. I have recompiled everyone and repackaged the jar but when I try to deploy the jar it gives me an error because the the local interface of the EJB does not have the old Java class parameter type.
    I have checked the jar, classes in the jar, and the ejb-jar.xml and weblogic-ejb-jar.xml in the jar and it is looks fine. I have cleaned out my server deployment directories and verified the classpath in case the older jar was in there and everything looks OK. It seems for some reason 8.1 is caching the old ejb-jar.xml or somehow is remembering the old method signature and will not process the updated jar. Has anyone seen anything like this?
    Thanks for any help or recommendations

    Can you show me the error you receive?
    Another simple test would be to deploy your application to a new, empty
    server.
    You can create a new domain as easy as this:
    mkdir testDomain;
    cd testDomain;
    java weblogic.Server
    Type in the username/password that you want and answer 'Yes' when it
    asks if you want to create a new domain.
    Try deploying your jar to this new domain, and let me know if it still
    fails.
    -- Rob
    Jeff Dooley wrote:
    Hi,
    I have an jar file under applications which I have deployed fine on WLS 8.1 in the past. I changed the method signature on one of the EJB classes in the jar. One of the parameters now takes a different Java class type. I have recompiled everyone and repackaged the jar but when I try to deploy the jar it gives me an error because the the local interface of the EJB does not have the old Java class parameter type.
    I have checked the jar, classes in the jar, and the ejb-jar.xml and weblogic-ejb-jar.xml in the jar and it is looks fine. I have cleaned out my server deployment directories and verified the classpath in case the older jar was in there and everything looks OK. It seems for some reason 8.1 is caching the old ejb-jar.xml or somehow is remembering the old method signature and will not process the updated jar. Has anyone seen anything like this?
    Thanks for any help or recommendations

  • Xmonad.hs - Invalid type signature

    Okay. I'm new in the world of Haskell and I have problem with xmonad's configurefile.
    My xmonad.hs looks like this:
    import XMonad
    import XMonad.Layout.LayoutModifier
    import XMonad.Layout.Spacing
    main = xmonad defaultConfig
    { terminal = "urxvt"
    , workspaces = ["α","β","γ","δ","ε","ζ","η","θ","ι"]
    , borderWidth = 1
    , normalBorderColor = "#EEEEEE"
    , focusedBorderColor = "#A979AA"
    , layoutHook = Spacing 2 $ Tall 1 (3/100) (1/2)
    Spacing :: Int -> l a -> ModifiedLayout Spacing l a
    And when I use command "xmonad --recompile" it gives me an error like this:
    xmonad.hs:15:0: Invalid type signature
    I have used thease modules:
    LayoutModifier
    Spacing
    So any idea how to fix this problem with invalid type signature?

    Scionar wrote:So any idea how to fix this problem with invalid type signature?
    1. A function like spacing starts with a lower-case letter, change that in line 12.
    2. You don't need to define the type signature of spacing, it's already defined in the module itself and gets imported along with the function when you import the Layout.Spacing module.
    Edit: And ninja'd again.
    Last edited by Runiq (2010-12-03 23:31:43)

  • Invalid method declaration

    Hi there,
    I have a problem to compile below sentences.
    import java.awt.* ;
    import javax.swing.* ;
    import java.awt.event.* ;
    public class p662 extends JFrame
    public ShowColors()
    ** invalid method declariration for ShowColors ****
    super ("Using colors") ;
    Please help me.
    Best regards

    What the diddley?
    Your class name is p662 (what the heck is that?).
    The declaration public ShowColors looks like a constructor. You call super in it with a String argument, which looks like you want to invoke a JFrame ctor.
    You can't invoke a super class constructor in any method except a class constructor. The class constructors must have the same name as the class. The class must go in a file whose name is the same as the public class inside.
    You should follow the Sun coding standards for naming:
    http://java.sun.com/docs/codeconv/html/CodeConvTOC.doc.html
    What are you doing here? This is unintelligible. - MOD

  • What is Invalid header signature error while using POI API

    Hello all,
    i'm using poi api for extracting the text part from word file while uploading using the POI api. it shows the error
    "Invalid header signature; read 3255307777713450285, expected -2226271756974174256"
    Can anyone help me solve the problem.
    Here's my code:
    <%@ page language="java" import="org.apache.poi.hwpf.extractor.*,java.io.*" %>
    <%-- String fil = request.getParameter("fil"); --%>
    <% ServletInputStream st = request.getInputStream();
    DataInputStream dis = new DataInputStream(st);
    WordExtractor woe = new WordExtractor(dis);%>
    <%String s = woe.getText();
    %>
    thanks a lot...

    Did you find any solution to that??? I am also stuck at such a place...

  • Deciding when to use "final" in method signatures

    Please consider this source code:
    public void foo(final Set<String> set) { ... }People who use this class don't need to know that the "set" reference is "final", right?
    Edited by: dpxqb on Apr 30, 2010 3:28 AM

    Kayaman wrote:
    They should be implicitly final so there would be no need for questions like this.I don't understand what that means.
    Or does someone here admit to having a habit of reassigning the parameters?I don't understand. I do it when it needs doing. Here is an example where I re-assigned the reference in the method signature:
    void foo(Writer w) {
      int i = 0;
      boolean hit = false;
      BufferedWriter bw = new BufferedWriter(w);
      Set<String> set = new HashSet<String>();
      bw.write(c);
      w.write(c); // no exception thrown. the object on the other end of the Writer will act weird
                  // which further masks the bug.
    }There are two working Writers going to the same location. There is no reason for this, it makes no sense, and it is a bug waiting to happen.
    This is how I got my BufferedWriter. Reassign the initial reference:
    void foo(Writer w) {
      if(! (w instanceof BufferedWriter)) {
        w = new BufferedWriter(w);
    }The only way to write is via a single object. It just prevents me from doing something stupid. I feel safer by eliminating unused references.

  • Changing exception clause in method signature when overwriting a method

    Hi,
    I stumbled upon a situation by accident and am not really clear on the details surrounding it. A short description:
    Say there is some API with interfaces Foo and Bar as follows:
    public interface Foo {
       void test() throws Exception;
    public interface Bar extends Foo {
       void test();
    }Now, I find it strange that method test() for interface Bar does not need to define Exception in its throws clause. When I first started with Java I was using Java 1.4.2; I now use Java 1.6. I cannot remember ever reading about this before and I have been unable to find an explanation or tutorial on how (or why) this works.
    Consider a more practical example:
    Say there is an API that uses RMI and defines interfaces as follwows:
    public interface RemoteHelper extends Remote {
       public Object select(int uid) throws RemoteException;
    public interface LocalHelper extends RemoteHelper {
       public Object select(int uid);
    }As per the RMI spec every method defined in a Remote interface must define RemoteException in its throws clause. The LocalHelper cannot be exported remotely (this will fail at runtime due to select() in LocalHelper not having RemoteException in its clause if I remember correctly).
    However, an implementing class for LocalHelper could represent a wrapper class for RemoteHelper, like this:
    public class Helper implements LocalHelper {
       private final RemoteHelper helper;
       public Helper(RemoteHelper helper) {
          this.helper = helper;
       public Object select(int id) {
          try {
             return (this.helper.select(id));
          } catch(RemoteException e) {
             // invoke app failure mechanism
    }This can uncouple an app from RMI dependancy. In more practical words: consider a webapp that contains two Servlets: a "startup" servlet and an "invocation" servlet. The startup servlet does nothing (always returns Method Not Allowed, default behaviour of HttpServlet), except locate an RMI Registry upon startup and look up some object bound to it. It can then make this object accessible to other classes through whatever means (i.e. a singleton Engine class).
    The invocation servlet does nothing upon startup, but simply calls some method on the previously acquired remote object. However, the invocation servlet does not need to know that the object is remote. Therefore, if the startup servlet wraps the remote object in another object (using the idea described before) then the invocation servlet is effectively removed from the RMI dependancy. The wrapper class can invoke some sort of failure mechanism upon the singleton engine (i.e. removing the remote object from memory) and optionally throw some other (optionally checked) exception (i.e. IllegalStateException) to the invocation servlet.
    In this way, the invocation servlet is not bound to RMI, there can be a single point where RemoteExceptions are handled and an unchecked exception (i.e. IllegalStateException) can be handled by the Servlet API through an exception error page, displaying a "Service Unavailable" message.
    Sorry for all this extensive text; I just typed out some thoughts. In short, my question is how and why can the throws clause change when overwriting a method? It's nothing I need though, except for the clarity (e.g. is this a bad practice to do?) and was more of an observation than a question.
    PS: Unless I'm mistaken, this is basically called the "Adapter" or "Bridge" (not sure which one it is) pattern (or a close adaptation to it) right (where one class is written to provide access to another class where the method signature is different)?
    Thanks for reading,
    Yuthura

    Yuthura wrote:
    I know it may throw any checked exception, but I'm pretty certain that an interface that extends java.rmi.Remote must include at least java.rmi.RemoteException in its throws clause (unless the spec has changed in Java 1.5/1.6).No.
    A method can always throw fewer exceptions than the one it's overriding. RMI has nothing to do with it.
    See Deitel & Deilte Advanced Java 2 Platform How To Program, 1st Ed. (ISBN 0-13-089650-1), page 793 (sorry, I couldn't find the RMI spec quick enough). Quote: "Each method in a Remote interface must have a throws clause that indicates that the method can throw RemoteException".Which means that there's always a possibility of RemoteException being thrown. That's a different issue. It's not becusae the parent class can throw RE. Rather, it's because some step that will always be followed is declared to throw RE.
    I later also noticed I could not add other checked exceptions, which made sense indeed. Your explanation made perfect sense now that I heard (read) it. But just to humour my curousity, has this always been possible? Yes, Java has always worked that way.
    PS: The overwriting/-riding was a grammatical typo (English is not my native language), but I meant to say what you said.No problem. Minor detail. It's a common mistake, but I always try to encourage proper terminology.

  • Method signature of a two dimensional array of an object

    Hi,
    Does anyone know how to set the method signature of a two dimensional array of an object (e.g. : String[][]).
    Thank you.

    using javap for the following function:
    public int testFunction(String myStr[][]);
    public int disconnectServer(java.lang.String[][]);
    /* ([[Ljava/lang/String;)I   */
    so the signature is:
    ([[Ljava/lang/String;)I                                                                                                                                                                                                                                                                                                                                                                                                                                                            

  • Error while installign AIR Application (invalid package signature errorID=5022)

    Hi All,
    I am new to Adobe AIR and facing error while Installing AIR application. This specially happens when in include a folder named "htmls" in the assets directory in my project.
    This folder have lots of html files and others folders. These file names have some special characters as well like ". & - _".
    However I can install the Application when I exclude this folder and everything works fine. Not able to find out the exact problem.
    Looking forward for help !!
    Log contents:
    .airappinstall
    failed while unpackaging: [ErrorEvent type="error" bubbles=false cancelable=false eventPhase=2 text="invalid package signature" errorID=5022]
    starting cleanup of temporary files
    application installer exiting
    .airinstall
    App installer failed; exit code 7
    begin quitting

    You may have found a bug in the AIR installer or packager. Given that the signature is an XML file, the "&" character seems the most likely culprit.
    The only short-term workaround is to identify which characters cause the problem and avoid using it.
    You should avoid the following characters in any case, since these cannot be used in file names on all platforms:
    Character            Hexcode
    various     0x00 - x1F
    *           x2A
    "           x22
    :           x3A
    >           x3C
    <           x3E
    ?           x3F
    \           x5C
    |           x7C

  • Question about changing method signature

    Hello. I've inherited some code which contains a method with the following signature:
    foo(int x, MyObject myObject)
    Okay, so that's not really the exact signature :) In any case, I need to modify the signature to:
    foo(int x, Object myObject)
    I believe that I can do this without affecting any existing client code because Obect is a superclass of MyObject. Is that right or must I deprecate the first version and add the second separately? Whatever, happens I can't break code which was compiled against the old version. Thanks in advance.
    -jason

    That's a good point. It's probably not an issue
    however as we don't provide (supported) access to our
    implementation classes. Thanks for the input.
    -JasonThen I don't see another issue with it, as long as no other internally-written class has already overridden it and doesn't get changed at the same time. In a sense you're saying it's a "private" (not necessarily in the same sense of the private keyword) method, so you can change the implementation, including method signatures, at your whim.

  • How to search OER for method signatures

    I would like to search OER for Service assets that have a specific input and/or output. I'm sure this is easy to do but am missing something.
    I was reading the description in the Sample Interface - Account Detail Interface shipped with OER and it says....
    "Users may search for particular method signatures, find this asset, and from here discover the services that implement this interface."
    That's what I want to do but am not sure how to do it. Can anyone explain how I would go about doing that?

    Try a simple search, put the method name in the search box, select the type as All Type. The search will list down the Interface and the Service that contains the api.

Maybe you are looking for