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I created a database on localhost, and wanted to pull this database to my Android, created two classes, CONEXAODAO, and Conexaomysql:
public class conexaoDAO {
public String tabelaDepartamento () {
String departamentoNome = "";
conexaoMysqlActivity conexao = new conexaoMysqlActivity();
conexaoActivity objConexao = new conexaoActivity();
objConexao.db_connect_string = "localhost";
objConexao.db_name = "souprogresso";
objConexao.db_userid = "root";
objConexao.db_password = "";
Connection conn = conexao.dbConnect(objConexao);
if (conn != null) {
try {
Statement statement = conn.createStatement();
String queryString = "SELECT nomeDepartamento, idprefeituraDepartamento FROM departamento WHERE idprefeituraDepartamento = '1'";
ResultSet rs;
rs = statement.executeQuery(queryString);
if (rs.next()) {
departamentoNome = rs.getString("nomeDepartamento");
System.out.println(departamentoNome);
}
} catch (SQLException e) {
departamentoNome = e.getMessage();
}
}
return departamentoNome;
}
}
public class conexaoMysqlActivity {
@SuppressLint("NewApi")
public Connection dbConnect(conexaoActivity objConexao) {
StrictMode.ThreadPolicy policy = new StrictMode.ThreadPolicy.Builder().permitAll().build();
StrictMode.setThreadPolicy(policy);
Connection conn = null;
String connectionUrl = null;
try {
Class.forName("com.mysql.jdbc.Driver");
connectionUrl = "jdbc:mysql://" +
objConexao.db_connect_string + ";" +
"databaseName=" + objConexao.db_name + ";user="
+objConexao.db_userid +
";password=" + objConexao.db_password + ";";
conn = DriverManager.getConnection(connectionUrl);
} catch (SQLException se) {
se.printStackTrace();
System.out.println("Não foi possível se conectar com a base de dados");
} catch (ClassNotFoundException e) {
e.printStackTrace();
System.out.println("Erro de Classe SQL");
} catch (Exception se) {
se.printStackTrace();
System.out.println("Erro de Expressão");
}
return conn;
}
}
When I try to rotate the following error happens:
08-14 17:48:30.149: E/AndroidRuntime(674): FATAL EXCEPTION: main
08-14 17:48:30.149: E/AndroidRuntime(674): java.lang.RuntimeException: Unable to instantiate activity ComponentInfo{br.com.example.secretario/br.com.example.secretario.conexaoMysqlActivity}: java.lang.ClassCastException: br.com.example.secretario.conexaoMysqlActivity cannot be cast to android.app.Activity
08-14 17:48:30.149: E/AndroidRuntime(674): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:1880)
08-14 17:48:30.149: E/AndroidRuntime(674): at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:1981)
08-14 17:48:30.149: E/AndroidRuntime(674): at android.app.ActivityThread.access$600(ActivityThread.java:123)
08-14 17:48:30.149: E/AndroidRuntime(674): at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1147)
08-14 17:48:30.149: E/AndroidRuntime(674): at android.os.Handler.dispatchMessage(Handler.java:99)
08-14 17:48:30.149: E/AndroidRuntime(674): at android.os.Looper.loop(Looper.java:137)
08-14 17:48:30.149: E/AndroidRuntime(674): at android.app.ActivityThread.main(ActivityThread.java:4424)
08-14 17:48:30.149: E/AndroidRuntime(674): at java.lang.reflect.Method.invokeNative(Native Method)
08-14 17:48:30.149: E/AndroidRuntime(674): at java.lang.reflect.Method.invoke(Method.java:511)
08-14 17:48:30.149: E/AndroidRuntime(674): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:784)
08-14 17:48:30.149: E/AndroidRuntime(674): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:551)
08-14 17:48:30.149: E/AndroidRuntime(674): at dalvik.system.NativeStart.main(Native Method)
08-14 17:48:30.149: E/AndroidRuntime(674): Caused by: java.lang.ClassCastException: br.com.example.secretario.conexaoMysqlActivity cannot be cast to android.app.Activity
08-14 17:48:30.149: E/AndroidRuntime(674): at android.app.Instrumentation.newActivity(Instrumentation.java:1023)
08-14 17:48:30.149: E/AndroidRuntime(674): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:1871)