Search Results

Search found 3838 results on 154 pages for 'throws'.

Page 21/154 | < Previous Page | 17 18 19 20 21 22 23 24 25 26 27 28  | Next Page >

  • Eclipse Java code Format

    - by Jayesh
    I am not that much aware of Eclipse Shortcuts. I copied code from some link and I pasted in Eclipse Indigo but it is coming like "public String doLogin() throws ApplicationException{ long executionStartTime = System.cu... }" I want to format it in java style like public String doLogin() throws ApplicationException{ long executionStartTime = System.cu... } I google it and found few shortcuts like, "Shift + Tab" , "Ctrl + I", "Ctrl + Shift + F". but is not giving me the behavior I want. is there I need to add custom formatter or I am expecting more.

    Read the article

  • How to access a field's value in an object using reflection

    - by kentcdodds
    My Question: How to overcome an IllegalAccessException to access the value of a an object's field using reflection. Expansion: I'm trying to learn about reflection to make some of my projects more generic. I'm running into an IllegalAccessException when trying to call field.getValue(object) to get the value of that field in that object. I can get the name and type just fine. If I change the declaration from private to public then this works fine. But in an effort to follow the "rules" of encapsulation I don't want to do this. Any help would be greatly appreciated! Thanks! My Code: package main; import java.lang.reflect.Field; public class Tester { public static void main(String args[]) throws Exception { new Tester().reflectionTest(); } public void reflectionTest() throws Exception { Person person = new Person("John Doe", "555-123-4567", "Rover"); Field[] fields = person.getClass().getDeclaredFields(); for (Field field : fields) { System.out.println("Field Name: " + field.getName()); System.out.println("Field Type: " + field.getType()); System.out.println("Field Value: " + field.get(person)); //The line above throws: Exception in thread "main" java.lang.IllegalAccessException: Class main.Tester can not access a member of class main.Tester$Person with modifiers "private final" } } public class Person { private final String name; private final String phoneNumber; private final String dogsName; public Person(String name, String phoneNumber, String dogsName) { this.name = name; this.phoneNumber = phoneNumber; this.dogsName = dogsName; } } } The Output: run: Field Name: name Field Type: class java.lang.String Exception in thread "main" java.lang.IllegalAccessException: Class main.Tester can not access a member of class main.Tester$Person with modifiers "private final" at sun.reflect.Reflection.ensureMemberAccess(Reflection.java:95) at java.lang.reflect.AccessibleObject.slowCheckMemberAccess(AccessibleObject.java:261) at java.lang.reflect.AccessibleObject.checkAccess(AccessibleObject.java:253) at java.lang.reflect.Field.doSecurityCheck(Field.java:983) at java.lang.reflect.Field.getFieldAccessor(Field.java:927) at java.lang.reflect.Field.get(Field.java:372) at main.Tester.reflectionTest(Tester.java:17) at main.Tester.main(Tester.java:8) Java Result: 1 BUILD SUCCESSFUL (total time: 0 seconds)

    Read the article

  • Make Directory.GetFiles() ignore protected folders

    - by Kryptic
    Hello Everyone, I'm using the Directory.GetFiles() method to get a list of files to operate on. This method throws an UnauthorizedAccessException for example when trying to access a protected folder. I would like it to simply skip over such folders and continue. How can I accomplish this with either Directory.GetFiles (preferably) or another method? Update: Here is the code that throws the exception. I am asking the user to select a directory and then retrieving the list of files. I commented out the code (so this is now whole method) that iterates through the files and the problem still occurs. The exception is thrown on the Directory.GetFiles() line. FolderBrowserDialog fbd = new FolderBrowserDialog(); DialogResult dr = fbd.ShowDialog(); if (dr == System.Windows.Forms.DialogResult.Cancel) return; string directory = fbd.SelectedPath; string[] files = Directory.GetFiles(directory, "*.html", SearchOption.AllDirectories);

    Read the article

  • Error with connection in my database servlet

    - by Zerobu
    Hello, I am writing a Database servlet, all seems well except that there seems to be an error in my connection import java.io.IOException; import java.sql.Connection; import java.sql.DriverManager; import java.sql.PreparedStatement; import java.sql.ResultSet; import java.sql.SQLException; import java.sql.Statement; import java.util.ArrayList; import javax.servlet.RequestDispatcher; import javax.servlet.ServletContext; import javax.servlet.ServletException; import javax.servlet.http.HttpServlet; import javax.servlet.http.HttpServletRequest; import javax.servlet.http.HttpServletResponse; public class DBServlet3 extends HttpServlet { private static final long serialVersionUID = 1L; @Override public void init() throws ServletException { super.init(); try { String jdbcDriverClass= getServletContext().getInitParameter( "jdbcDriverClass" ); if (jdbcDriverClass == null) throw new ServletException( "Could not find jdbcDriverClass initialization parameter" ); Class.forName( jdbcDriverClass ); } catch (ClassNotFoundException e) { throw new ServletException( "Could not load JDBC driver class", e ); } } @Override protected void doGet( HttpServletRequest request, HttpServletResponse response ) throws ServletException, IOException { RequestDispatcher dispatcher= request.getRequestDispatcher( "/db.jsp" ); ServletContext application= getServletContext(); ArrayList<String> names= new ArrayList<String>(); try { Connection connection= null; Statement statement= null; ResultSet results= null; try { String jdbcUrl= application.getInitParameter( "jdbcUrl" ); String jdbcUser= application.getInitParameter( "jdbcUser" ); String jdbcPassword= application.getInitParameter( "jdbcPassword" ); connection= DriverManager.getConnection( jdbcUrl, jdbcUser, jdbcPassword ); statement= connection.createStatement(); results= statement.executeQuery( "SELECT * FROM students" ); while (results.next()) { String name= results.getString( "name" ); names.add( name ); } } finally { if (results != null) results.close(); if (statement != null) statement.close(); if (connection != null) connection.close(); } } catch (SQLException e) { throw new ServletException( e ); } request.setAttribute( "names", names ); dispatcher.forward( request, response ); } @Override protected void doPost( HttpServletRequest request, HttpServletResponse response ) throws ServletException, IOException { String sql= "INSERT INTO students VALUES (" + request.getParameter( "id" ) + ", '" + request.getParameter( "name" ) + "')"; sql= "INSERT INTO students VALUES (?, ?, ?, ?)"; PreparedStatement statement= connection.prepareStatement( sql ); //error on this line statement.setString( 1, request.getParameter( "id" ) ); statement.setString( 2, request.getParameter( "name" ) ); } }

    Read the article

  • Exception is swallowed by finally

    - by fiction
    static int retIntExc() throws Exception{ int result = 1; try { result = 2; throw new IOException("Exception rised."); } catch (ArrayIndexOutOfBoundsException e) { System.out.println(e.getMessage()); result = 3; } finally { return result; } } A friend of mine is a .NET developer and currently migrating to Java and he ask me the following question about this source. In theory this must throw IOException("Exception rised.") and the whole method retIntExc() must throws Exception. But nothing happens, the method returns 2. I've not tested his example, but I think that this isn't the expected behavior. EDIT: Thanks for all answers. Some of you have ignored the fact that method is called retIntExc, which means that this is only some test/experimental example, showing problem in throwing/catching mechanics. I didn't need 'fix', I needed explanation why this happens.

    Read the article

  • Are macro definitions compatible between MIPS and Intel C compiler?

    - by Derek
    I seem to be having a problem with a macro that I have defined in a C program. I compile this software and run it sucessfully with the MIPS compiler. It builds OK but throws the error "Segmentation fault" at runtime when using icc. I compiled both of these on 64 bit architectures (MIPS on SGI, with -64 flag and icc on an intel platform). Is there some magic switch I need to use to make this work correctly on both system? I turned on warnings for the intel compiler, and EVERY one of the places in my program where a macro is invoked throws a warning. Usually something along the lines of mismatched types on the macro's parameters (int to char *) or some such thing.

    Read the article

  • sqlite3.OperationalError: database is locked - non-threaded application

    - by James C
    Hi, I have a Python application which throws the standard sqlite3.OperationalError: database is locked error. I have looked around the internet and could not find any solution which worked (please note that there is no multiprocesses/threading going on, and as you can see I have tried raising the timeout parameter). The sqlite file is stored on the local hard drive. The following function is one of many which accesses the sqlite database, and runs fine the first time it is called, but throws the above error the second time it is called (it is called as part of a for loop in another function): def update_index(filepath): path = get_setting('Local', 'web') stat = os.stat(filepath) modified = stat.st_mtime index_file = get_setting('Local', 'index') connection = sqlite3.connect(index_file, 30) cursor = connection.cursor() head, tail = os.path.split(filepath) cursor.execute('UPDATE hwlive SET date=? WHERE path=? AND name=?;', (modified, head, tail)) connection.commit() connection.close() Many thanks.

    Read the article

  • Copy image to BLOB from client pc aka Java function in Oracle

    - by mumich
    Hi guys, I've been stuck with this for past two days. I've go java function stored in Oracle system which is supposed to copy image from local drive do remote database and store it in BLOB - it's called CopyBLOB and looks like this: import java.sql.*; import oracle.sql.*; import java.io.*; public class CopyBLOB { static int id; static String fileName = null; static Connection conn = null; public CopyBLOB(int idz, String f) { id = idz; fileName = f; } public static void copy(int ident, String path) throws SQLException, FileNotFoundException { CopyBLOB cpB = new CopyBLOB(ident, path); cpB.getConnection(); cpB.callUpdate(id, fileName); } public void getConnection() throws SQLException { DriverManager.registerDriver (new oracle.jdbc.OracleDriver()); try { conn = DriverManager.getConnection("jdbc:oracle:thin:@oraserv.ms.mff.cuni.cz:1521:db", "xxx", "xxx"); } catch (SQLException sqlex) { System.out.println("SQLException while getting db connection: "+sqlex); if (conn != null) conn.close(); } catch (Exception ex) { System.out.println("Exception while getting db connection: "+ex); if (conn != null) conn.close(); } } public void callUpdate(int id, String file ) throws SQLException, FileNotFoundException { CallableStatement cs = null; try { conn.setAutoCommit(false); File f = new File(file); FileInputStream fin = new FileInputStream(f); cs = (CallableStatement) conn.prepareCall( "begin add_image(?,?); end;" ); cs.setInt(1, id ); cs.setBinaryStream(2, fin, (int) f.length()); cs.execute(); conn.setAutoCommit(true); } catch ( SQLException sqlex ) { System.out.println("SQLException in callUpdateUsingStream method of given status : " + sqlex.getMessage() ); } catch ( FileNotFoundException fnex ) { System.out.println("FileNotFoundException in callUpdateUsingStream method of given status : " + fnex.getMessage() ); } finally { try { if (cs != null) cs.close(); if (conn != null) conn.close(); } catch ( Exception ex ) { System.out.println("Some exception in callUpdateUsingStream method of given status : " + ex.getMessage( ) ); } } } } The wrapper function is defined in package "MyPackage" as folows: procedure image_adder( id varchar2, path varchar2 ) AS language java name 'CopyBLOB.copy(java.lang.String, java.lang.String)'; And the inserting function called image_add is as simple as this: procedure add_image( id numeric(10), pic blob) AS BEGIN insert into pictures values (seq_pic.nextval, id, pic); END add_image; Now the problem: When I type call MyPackage.image_adder(1, 'd:\samples\img.jpg'); I get the ORA-29531 Error: No method copy in class CopyBLOB. Can you help me, please?

    Read the article

  • How to get the action from the HttpServlet request to dispatch to multiple pages

    - by JFB
    I am using the Page Controller pattern. How could I use the same controller for two different pages by detecting the request action and then dispatching according to the result? Here is my code: account.jsp <form name="input" action="<%=request.getContextPath() %>/edit" method="get"> <input type="submit" value="Modifier" /> </form> Account Servlet public void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { System.out.println("received HTTP GET"); String action = request.getParameter("action"); if (action == null) { // the account page dispatch(request, response, "/account"); } else if (action == "/edit") { // the popup edit page dispatch(request, response, "/edit"); } protected void dispatch(HttpServletRequest request, HttpServletResponse response, String page) throws javax.servlet.ServletException, java.io.IOException { RequestDispatcher dispatcher = getServletContext() .getRequestDispatcher(page); dispatcher.forward(request, response); } }

    Read the article

  • I have a ConnectException that isn't being caught for some reason

    - by aakbari1024
    I'm working on an Android application that uses sockets. I have a function called initializeStreams() which opens the socket and attempts a connection. This function throws a ConnectException if the connection could not be established. But for some reason, in the code that calls initializeStreams(), which has a catch block for ConnectException, the log prints out its own stack trace for the exception instead of going to the catch block. The catch block is never reached at all, even though the exact exception is being thrown. Here's the code: The try block: try { initializeStreams(); /* drivesList = new ArrayList<String>(); drivesList = enumerateDrives();*/ } catch (ConnectException e) { //Log.i(TAG, "caught connect exception"); /*loadingProgress.dismiss(); retryConnection();*/ } initializeStreams(): public void initializeStreams() throws ConnectException { try { Log.i(TAG, "Attempting to connect"); requestSocket = new Socket(SERVER_ADDR, PORT); /* other code */ } catch (IOException e) { e.printStackTrace(); } I can't figure this out, so any help would be much appreciated. }

    Read the article

  • doubt in Exceptions

    - by Ajay Singh
    class MyException extends Exception { MyException() {} MyException(String msg) { super(msg);} } public class NewException { static void f() throws MyException { System.out.println("throwing exception from f()"); throw new ClassCastException(); } static void g() throws MyException { System.out.println("throwing exception from g()"); throw new MyException("parametrized "); } public static void main(String ...strings ) { try { f(); } catch(MyException e) { e.printStackTrace(System.out); } try { g(); } catch(MyException e) { e.printStackTrace(System.out); } } } In the function f() iam specifying that "MyException " exception will be thrown and actually iam throwing some other exception which has no relation with MyException but still the compiler does not report any complain.Why is it so??

    Read the article

  • Parsing XHTML results from Bing

    - by Nir
    Hello, i am trying to parse received search queries from bing search engines which are received in xhtml in java. I am using sax XmlReader to read the results but i keep on getting errors. here is my code-this one is for the hadler of the reader: import org.xml.sax.Attributes; import org.xml.sax.SAXException; import org.xml.sax.helpers.DefaultHandler; public class XHTMLHandler extends DefaultHandler{ public XHTMLHandler() { super(); } public void startDocument () { System.out.println("Start document"); } public void endDocument () { System.out.println("End document"); } public void startElement (String uri, String name,String qName, Attributes atts) { if ("".equals (uri)) System.out.println("Start element: " + qName); else System.out.println("Start element: {" + uri + "}" + name); } public void endElement (String uri, String name, String qName) { if ("".equals (uri)) System.out.println("End element: " + qName); else System.out.println("End element: {" + uri + "}" + name); } public void startPrefixMapping (String prefix, String uri) throws SAXException { } public void endPrefixMapping (String prefix) throws SAXException { } public void characters (char ch[], int start, int length) { System.out.print("Characters: \""); for (int i = start; i < start + length; i++) { switch (ch[i]) { case '\\': System.out.print("\\\\"); break; case '"': System.out.print("\\\""); break; case '\n': System.out.print("\\n"); break; case '\r': System.out.print("\\r"); break; case '\t': System.out.print("\\t"); break; default: System.out.print(ch[i]); break; } } System.out.print("\"\n"); } } and this is the program itself: import java.io.BufferedReader; import java.io.IOException; import java.io.InputStreamReader; import java.io.OutputStreamWriter; import java.net.HttpRetryException; import java.net.HttpURLConnection; import java.net.URL; import org.xml.sax.InputSource; import org.xml.sax.SAXException; import org.xml.sax.XMLReader; import org.xml.sax.helpers.XMLReaderFactory; public class Searching { private String m_urlBingSearch = "http://www.bing.com/search?q="; private HttpURLConnection m_httpCon; private OutputStreamWriter m_streamWriter; //private BufferedReader m_bufferReader; private URL m_serverAdress; private StringBuilder sb; private String m_line; private InputSource m_inputSrc; public Searching() { m_httpCon = null; m_streamWriter = null; //m_bufferReader = null; m_serverAdress = null; sb = null; m_line = new String(); } public void SearchBing(String searchPrms) throws SAXException,IOException { //set up connection sb = new StringBuilder(); sb.append(m_urlBingSearch); sb.append(searchPrms); m_serverAdress = new URL(sb.toString()); m_httpCon = (HttpURLConnection)m_serverAdress.openConnection(); m_httpCon.setRequestMethod("GET"); m_httpCon.setDoOutput(true); m_httpCon.setConnectTimeout(10000); m_httpCon.connect(); //m_streamWriter = new OutputStreamWriter(m_httpCon.getOutputStream()); //m_bufferReader = new BufferedReader(new InputStreamReader(m_httpCon.getInputStream())); XMLReader reader = XMLReaderFactory.createXMLReader(); XHTMLHandler handle = new XHTMLHandler(); reader.setContentHandler(handle); reader.setErrorHandler(handle); //reader.startPrefixMapping("html", "http://www.w3.org/1999/xhtml"); handle.startPrefixMapping("html", "http://www.w3.org/1999/xhtml"); m_inputSrc = new InputSource(m_httpCon.getInputStream()); reader.parse(m_inputSrc); m_httpCon.disconnect(); } public static void main(String [] args) throws SAXException,IOException { Searching s = new Searching(); s.SearchBing("beatles"); } } this is my error message: Exception in thread "main" java.io.IOException: Server returned HTTP response code: 503 for URL: http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd at sun.net.www.protocol.http.HttpURLConnection.getInputStream(Unknown Source) at com.sun.org.apache.xerces.internal.impl.XMLEntityManager.setupCurrentEntity(Unknown Source) at com.sun.org.apache.xerces.internal.impl.XMLEntityManager.startEntity(Unknown Source) at com.sun.org.apache.xerces.internal.impl.XMLEntityManager.startDTDEntity(Unknown Source) at com.sun.org.apache.xerces.internal.impl.XMLDTDScannerImpl.setInputSource(Unknown Source) at com.sun.org.apache.xerces.internal.impl.XMLDocumentScannerImpl$DTDDriver.dispatch(Unknown Source) at com.sun.org.apache.xerces.internal.impl.XMLDocumentScannerImpl$DTDDriver.next(Unknown Source) at com.sun.org.apache.xerces.internal.impl.XMLDocumentScannerImpl$PrologDriver.next(Unknown Source) at com.sun.org.apache.xerces.internal.impl.XMLDocumentScannerImpl.next(Unknown Source) at com.sun.org.apache.xerces.internal.impl.XMLNSDocumentScannerImpl.next(Unknown Source) at com.sun.org.apache.xerces.internal.impl.XMLDocumentFragmentScannerImpl.scanDocument(Unknown Source) at com.sun.org.apache.xerces.internal.parsers.XML11Configuration.parse(Unknown Source) at com.sun.org.apache.xerces.internal.parsers.XML11Configuration.parse(Unknown Source) at com.sun.org.apache.xerces.internal.parsers.XMLParser.parse(Unknown Source) at com.sun.org.apache.xerces.internal.parsers.AbstractSAXParser.parse(Unknown Source) at Searching.SearchBing(Searching.java:57) at Searching.main(Searching.java:65) can someone please help? i think it has something to do with dtd but i don't know hot to fix it

    Read the article

  • File.Exists() returns false, but not in debug

    - by Tor Haugen
    I'm being completely confused here folks, My code throws an exception because File.Exists() returns false public override sealed TCargo ReadFile(string fileName) { if (!File.Exists(fileName)) { throw new ArgumentException("Provided file name does not exist", "fileName"); } Visual studio breaks at the throw statement, and I immediately check the value of File.Exists(fileName) in the immediate window. It returns true. When I drag the breakpoint back up to the if statement and execute it again, it throws again. fileName is an absolute path to a file. I'm not creating the file, nor writing to it (it's there all along). If I paste the path into the open dialog in Notepad, it reads the file without problems. The code is executing in a background worker. It's the only complicating factor I can think of. I am positive the file has not been opened already, either in the worker thread or elsewhere. What's going on here?

    Read the article

  • Implementing Clonable in Java

    - by Artium
    In which cases should I use this way: public A clone() throws CloneNotSupportedException { A clone = (A)super.clone(); clone.x= this.x; return clone; } And in which cases should I use that way: public ShiftedStack clone() throws CloneNotSupportedException { return new A(this.x); } What should I do if x is final and I want to use the first way? Regarding the first way, I understand it like this: we clone the super class and up-cast it, leading to some members uninitialized. After this initialize these members. Is my understanding correct? Thank you.

    Read the article

  • SwingWorker exceptions lost even when using wrapper classes

    - by Ti Strga
    I've been struggling with the usability problem of SwingWorker eating any exceptions thrown in the background task, for example, described on this SO thread. That thread gives a nice description of the problem, but doesn't discuss recovering the original exception. The applet I've been handed needs to propagate the exception upwards. But I haven't been able to even catch it. I'm using the SimpleSwingWorker wrapper class from this blog entry specifically to try and address this issue. It's a fairly small class but I'll repost it at the end here just for reference. The calling code looks broadly like try { // lots of code here to prepare data, finishing with SpecialDataHelper helper = new SpecialDataHelper(...stuff...); helper.execute(); } catch (Throwable e) { // used "Throwable" here in desperation to try and get // anything at all to match, including unchecked exceptions // // no luck, this code is never ever used :-( } The wrappers: class SpecialDataHelper extends SimpleSwingWorker { public SpecialDataHelper (SpecialData sd) { this.stuff = etc etc etc; } public Void doInBackground() throws Exception { OurCodeThatThrowsACheckedException(this.stuff); return null; } protected void done() { // called only when successful // never reached if there's an error } } The feature of SimpleSwingWorker is that the actual SwingWorker's done()/get() methods are automatically called. This, in theory, rethrows any exceptions that happened in the background. In practice, nothing is ever caught, and I don't even know why. The SimpleSwingWorker class, for reference, and with nothing elided for brevity: import java.util.concurrent.ExecutionException; import javax.swing.SwingWorker; /** * A drop-in replacement for SwingWorker<Void,Void> but will not silently * swallow exceptions during background execution. * * Taken from http://jonathangiles.net/blog/?p=341 with thanks. */ public abstract class SimpleSwingWorker { private final SwingWorker<Void,Void> worker = new SwingWorker<Void,Void>() { @Override protected Void doInBackground() throws Exception { SimpleSwingWorker.this.doInBackground(); return null; } @Override protected void done() { // Exceptions are lost unless get() is called on the // originating thread. We do so here. try { get(); } catch (final InterruptedException ex) { throw new RuntimeException(ex); } catch (final ExecutionException ex) { throw new RuntimeException(ex.getCause()); } SimpleSwingWorker.this.done(); } }; public SimpleSwingWorker() {} protected abstract Void doInBackground() throws Exception; protected abstract void done(); public void execute() { worker.execute(); } }

    Read the article

  • Expected symbol problems with this function declaration

    - by Derek
    I am just getting back into the C programming realm and I am having an issue that I think is linker related. I am using cmake for the first time as well, so that could be adding to my frustration. I have included a third party header file that contains a typedef that my code is trying to use, and it has this line: typedef struct a a_t so my code has a_t *var; //later..... var->member;// this line throws the error which throws the error: dereferencing pointer to incomplete type So am I just missing another include file, or is this a linker issue? I am building this code in QtCreator and using cmake. I can dive on a_t to see that typedef declaration in the included header, but I can't seem to dive on "struct a" itself to see where it's coming from. Thanks

    Read the article

  • Declare global variables for a batch of execution statements - sql server 2005

    - by Shrewd Demon
    hi, i have an SQL statement wherein i am trying to update the table on the client's machine. the sql statement is as follows: BEGIN TRANSACTION DECLARE @CreatedBy INT SELECT @CreatedBy = [User_Id] FROM Users WHERE UserName = 'Administrator' --//////////////////////////////////////////////////////////////////// --//////////////////////////////////////////////////////////////////// PRINT @CreatedBy --(Works fine here and shows me the output) PRINT N'Rebuilding [dbo].[Some_Master]' ALTER TABLE [dbo].[Some_Master] ADD [CreatedBy] [BIGINT] NULL, [Reason] [VARCHAR](200) NULL GO PRINT @CreatedBy --(does not work here and throws me an error) PRINT N'Updating data in [Some_Master] table' UPDATE Some_Master SET CreatedBy = @CreatedBy COMMIT TRANSACTION but i am getting the following error: Must declare the scalar variable "@CreatedBy". Now i have observed if i write the Print statement above the alter command it works fine and shows me its value, but if i try to print the value after the Alter command it throws me the error i specified above. I dont know why ?? please help! Thank you

    Read the article

  • Exception and Inheritance in JAVA

    - by user1759950
    Suppose we have this problem public class Father{ public void method1(){...} } public class Child1 extends Father{ public void method1() throws Exception{ super.method1(); ... } } Child1 extends Father and override method1 but given implementation Child1.method1 now throws a exception, this wont compile as override method can't throw new exceptions. What is the best solution? Propagate the required exception to the Father.. to me this is against encapsulation, inheritance and general OOP ( the father potentially throw and exception that will never happen ) Use a RuntimeException instead? This solution wont propagate the Exception to the father but I read In Oracle docs and others sources states class of exceptions should be used when "Client code cannot do anything" this is not that case, this exception will b useful to recover blablabla ( why is wrong to use RuntimeException instead? ) Other.. thanks, Federico

    Read the article

  • Trying to understand Java RSA key size

    - by Tom Brito
    The key generator was initilized with a size of 1024, so why the printed sizes are 635 and 162? import java.security.KeyPair; import java.security.KeyPairGenerator; import java.security.NoSuchAlgorithmException; import java.security.NoSuchProviderException; import java.security.interfaces.RSAPrivateKey; import java.security.interfaces.RSAPublicKey; public class TEST { public static KeyPair generateKeyPair() throws NoSuchAlgorithmException, NoSuchProviderException { KeyPairGenerator keyPairGenerator = KeyPairGenerator.getInstance("RSA", "BC"); keyPairGenerator.initialize(1024); return keyPairGenerator.generateKeyPair(); } public static void main(String[] args) throws Exception { KeyPair keyPair = generateKeyPair(); RSAPrivateKey privateKey = (RSAPrivateKey) keyPair.getPrivate(); RSAPublicKey publicKey = (RSAPublicKey) keyPair.getPublic(); System.out.println("Size = " + privateKey.getEncoded().length); System.out.println("Size = " + publicKey.getEncoded().length); } }

    Read the article

  • The big last_insert_id() problem, again.

    - by wretrOvian
    Note - this follows my question here: http://stackoverflow.com/questions/2983685/jdbc-does-the-connection-break-if-i-lose-reference-to-the-connection-object Now i have a created a class so i can deal with JDBC easily for the rest of my code - public class Functions { private String DB_SERVER = ""; private String DB_NAME = "test"; private String DB_USERNAME = "root"; private String DB_PASSWORD = "password"; public Connection con; public PreparedStatement ps; public ResultSet rs; public ResultSetMetaData rsmd; public void connect() throws java.io.FileNotFoundException, java.io.IOException, SQLException, Exception { String[] dbParms = Parameters.load(); DB_SERVER = dbParms[0]; DB_NAME = dbParms[1]; DB_USERNAME = dbParms[2]; DB_PASSWORD = dbParms[3]; // Connect. Class.forName("com.mysql.jdbc.Driver").newInstance(); con = DriverManager.getConnection("jdbc:mysql://" + DB_SERVER + "/" + DB_NAME, DB_USERNAME, DB_PASSWORD); } public void disconnect() throws SQLException { // Close. con.close(); } } As seen Parameters.load() refreshes the connection parameters from a file every-time, so that any changes to the same may be applied on the next immediate connection. An example of this class in action - public static void add(String NAME) throws java.io.FileNotFoundException, java.io.IOException, SQLException, Exception { Functions dbf = new Functions(); dbf.connect(); String query = "INSERT INTO " + TABLE_NAME + "(" + "NAME" + ") VALUES(?)"; PreparedStatement ps = dbf.con.prepareStatement(query); ps.setString(1, NAME); ps.executeUpdate(); dbf.disconnect(); } Now here is the problem - for adding a record to the table above, the add() method will open a connection, add the record - and then call disconnect() . What if i want to get the ID of the inserted record after i call add() -like this : Department.add("new dept"); int ID = getlastID(); Isn't it possible that another add() was called between those two statements?

    Read the article

  • Can SQLite file copied successfully on the data folder of an unrooted android device ?

    - by student
    I know that in order to access the data folder on the device, it needs to be rooted. However, if I just want to copy the database from my assets folder to the data folder on my device, will the copying process works on an unrooted phone? The following is my Database Helper class. From logcat, I can verify that the methods call to copyDataBase(), createDataBase() and openDataBase() are returned successfully. However, I got this error message android.database.sqlite.SQLiteException: no such table: TABLE_NAME: when my application is executing rawQuery. I'm suspecting the database file is not copied successfully (cannot be too sure as I do not have access to data folder), yet the method call to copyDatabase() are not throwing any exception. What could it be? Thanks. ps: My device is still unrooted, I hope it is not the main cause of the error. public DatabaseHelper(Context context) { super(context, DB_NAME, null, 1); this.myContext = context; } public void createDataBase() throws IOException{ boolean dbExist = checkDataBase(); String s = new Boolean(dbExist).toString(); Log.d("dbExist", s ); if(dbExist){ //do nothing - database already exist Log.d("createdatabase","DB exists so do nothing"); }else{ this.getReadableDatabase(); try { copyDataBase(); Log.d("copydatabase","Successful return frm method call!"); } catch (IOException e) { throw new Error("Error copying database"); } } } private boolean checkDataBase(){ File dbFile = new File(DB_PATH + DB_NAME); return dbFile.exists(); } private void copyDataBase() throws IOException{ //Open your local db as the input stream InputStream myInput = null; myInput = myContext.getAssets().open(DB_NAME); Log.d("copydatabase","InputStream successful!"); // Path to the just created empty db String outFileName = DB_PATH + DB_NAME; //Open the empty db as the output stream OutputStream myOutput = new FileOutputStream(outFileName); //transfer bytes from the inputfile to the outputfile byte[] buffer = new byte[1024]; int length; while ((length = myInput.read(buffer))>0){ myOutput.write(buffer, 0, length); } //Close the streams myOutput.flush(); myOutput.close(); myInput.close(); } public void openDataBase() throws SQLException{ //Open the database String myPath = DB_PATH + DB_NAME; myDataBase = SQLiteDatabase.openDatabase(myPath, null, SQLiteDatabase.OPEN_READONLY); } /* @Override public synchronized void close() { if(myDataBase != null) myDataBase.close(); super.close(); }*/ public void close() { // NOTE: openHelper must now be a member of CallDataHelper; // you currently have it as a local in your constructor if (myDataBase != null) { myDataBase.close(); } } @Override public void onCreate(SQLiteDatabase db) { } @Override public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) { } }

    Read the article

  • Roll back changes to object if invalid

    - by hhravn
    How do i roll back changes to an attached object in nhibernate? We have a validation before update/save (example simplified).. var setting = Get("key") setting.Value = "helo" //for whatever reason, this particular //setting cannot have its value saved to the database ... Verify(setting); //throws base.Update(setting); but since the object is attached, any changes already happened in the session, even if the validation throws, and never reaches Update. What is the proper way to handle this?

    Read the article

  • Dev Environment Tests Not 100% Compatible with Staging/Production in Rails

    - by aronchick
    We use a bunch of specific apps/APIs that (unfortunately) differ quite a bit from dev to staging/production. We use tests and continuous integration at each stage, but in dev, the tests fail annoyingly (throwing dialogs, etc - thanks Windows for the 64-bit notification!). I hate to write custom code, but are there some best practices for how to allow a subset of testing in ruby/rails - or for patching out specific tests when you're running on Windows? Some specific situations that: Identify.exe does not support 64-bit Windows and throws a dialog. Sethostname is not supported, and throws an error (at least it's command line).

    Read the article

  • Default http/admin port in dropwizard project

    - by mithrandir
    I have a dropwizard project and I have maintained a config.yml file at the ROOT of the project (basically at the same level as pom.xml). Here I have specified the HTTP port to be used as follows: http: port:9090 adminPort:9091 I have the following code in my TestService.java file public class TestService extends Service<TestConfiguration> { @Override public void initialize(Bootstrap<TestConfiguration> bootstrap) { bootstrap.setName("test"); } @Override public void run(TestConfiguration config, Environment env) throws Exception { // initialize some resources here.. } public static void main(String[] args) throws Exception { new TestService().run(new String[] { "server" }); } } I expect the config.yml file to be used to determine the HTTP port. However the app always seems to start with the default ports 8080 and 8081. Also note that I am running this from eclipse. Any insights as to what am I doing wrong here ?

    Read the article

  • In a JDBC ResultSet, what should happen when getLong() or getShort() is called on an int result colu

    - by Uri
    Say that I have a JDBC ResultSet, and I call the getLong() or getshort() method. For which of the following SQL types {SMALLINT, INT, BIGINT} should I get long, and for which types should I get an error? In other words, if I have an INT and I want a SMALLINT (A short), would I get it, or would I get an error? Similarly, if I have an INT and want a BIGINT (a long), would I get it, or would I get an error? The Javadocs (listed below) say nothing. public long getLong(int columnIndex) throws SQLException Retrieves the value of the designated column in the current row of this ResultSet object as a long in the Java programming language. Parameters: columnIndex - the first column is 1, the second is 2, ... Returns: the column value; if the value is SQL NULL, the value returned is 0 Throws: SQLException - if a database access error occurs

    Read the article

< Previous Page | 17 18 19 20 21 22 23 24 25 26 27 28  | Next Page >