Example usage for java.lang Class forName

Introduction

In this page you can find the example usage for java.lang Class forName.

Prototype

@CallerSensitive
public static Class<?> forName(String className) throws ClassNotFoundException

Source Link

Document

Returns the Class object associated with the class or interface with the given string name.

Usage

From source file:X.java

public static void main(String[] args) throws Exception {
    Class<?> clazz = Class.forName("X");
    X x = (X) clazz.newInstance();//from w w w.  j av  a 2 s.c om
    Field f = clazz.getField("i");
    System.out.println(f.getInt(x)); // Output: 10
    f.setInt(x, 20);
    System.out.println(f.getInt(x)); // Output: 20
    f = clazz.getField("PI");
    System.out.println(f.getDouble(null)); // Output: 3.14
    f.setDouble(x, 20);
}

From source file:Main.java

public static void main(String[] args) throws Exception {
    Connection connection = null;
    Class.forName("com.mysql.jdbc.Driver");

    String url = "jdbc:mysql://localhost/testdb";
    String user = "root";
    String password = "";
    connection = DriverManager.getConnection(url, user, password);

    Statement stmt = connection.createStatement();
    String sql = "INSERT INTO users (name, address) VALUES ('Foo', 'Street')";
    stmt.execute(sql);//  ww  w .  j  a v  a2 s  .com
    connection.close();
}

From source file:Main.java

public static void main(String args[]) throws Exception {
    Class.forName("sun.jdbc.odbc.JdbcOdbcDriver");
    String URL = "jdbc:odbc:dbName";
    Connection conn = DriverManager.getConnection(URL, "user", "passw");

    DatabaseMetaData dmd = conn.getMetaData();
    ResultSet rs1 = dmd.getSchemas();
    while (rs1.next()) {
        String ss = rs1.getString(1);
        ResultSet rs2 = dmd.getTables(null, ss, "%", null);
        while (rs2.next())
            System.out.println(rs2.getString(3) + " " + rs2.getString(4));
    }/*  w  w  w .  j  a va 2s  .co  m*/
    conn.close();
}

From source file:MainClass.java

public static void main(String args[]) throws Exception {

    try {/*w  ww.  j  ava2s  .c o  m*/
        Class c = Class.forName("java.text.NumberFormat");
        Method m = c.getMethod("getInstance");
        Object ret = m.invoke(null);
        System.out.println("Results: " + ret);
    } catch (ClassNotFoundException e) {
        System.out.println("Class.forName(  ) can't find the class");
    } catch (NoSuchMethodException e2) {
        System.out.println("method doesn't exist");
    } catch (IllegalAccessException e3) {
        System.out.println("no permission to invoke that method");
    } catch (InvocationTargetException e) {
        System.out.println("an exception ocurred while invoking that method");
        System.out.println("Method threw an: " + e.getTargetException());
    }
}

From source file:Main.java

public static void main(String[] args) {
    String name = "java.util.Date";
    try {/*from w  w w .j  a  v  a2 s . c o m*/
        Class cl = Class.forName(name);
        System.out.println("class " + name);
        System.out.println("Its methods:");
        printFields(cl);
        System.out.println();
    } catch (ClassNotFoundException e) {
        System.out.println("Class not found.");
    }
}

From source file:Main.java

public static void main(String[] argv) throws Exception {
    Connection con = null;//ww w  .j  ava2  s.c o  m

    Class.forName("com.mysql.jdbc.Driver");
    con = DriverManager.getConnection("jdbc:mysql://localhost:3306/jdbctutorial", "root", "root");

    String sql = "INSERT datatypes VALUES(?,?,?)";
    PreparedStatement prest = con.prepareStatement(sql);
    prest.setByte(1, (byte) 5);
    prest.setShort(2, (short) 65);
    prest.setLong(3, (long) 254);
    int row = prest.executeUpdate();
    System.out.println(row + " row(s) affected)");
}

From source file:Main.java

public static void main(String[] args) throws Exception {
    Class.forName("org.apache.derby.jdbc.ClientDriver");
    Connection con = DriverManager.getConnection("jdbc:derby://localhost:1527/testDb", "name", "pass");
    Statement stmt = con.createStatement(ResultSet.TYPE_SCROLL_SENSITIVE, ResultSet.CONCUR_UPDATABLE);
    String insertEmp1 = "insert into emp values(10,'A','trainee')";
    String insertEmp2 = "insert into emp values(11,'B','trainee')";
    String insertEmp3 = "insert into emp values(12,'C','trainee')";
    con.setAutoCommit(false);//w ww  .  j a v  a 2  s  .  c  om
    stmt.addBatch(insertEmp1);
    stmt.addBatch(insertEmp2);
    stmt.addBatch(insertEmp3);
    ResultSet rs = stmt.executeQuery("select * from emp");
    rs.last();
    System.out.println("rows before batch execution= " + rs.getRow());
    stmt.executeBatch();
    con.commit();
    System.out.println("Batch executed");
    rs = stmt.executeQuery("select * from emp");
    rs.last();
    System.out.println("rows after batch execution= " + rs.getRow());
}

From source file:RectangleFields.java

public static void main(String args[]) {
    Class rectClass = null;//from   w w w  .j av a2  s .c  om
    Field rectField[] = null;

    try {
        rectClass = Class.forName("java.awt.Rectangle");
        rectField = rectClass.getDeclaredFields();
    } catch (SecurityException se) {
        System.out.println("Access to Rectangle fields denied");
    } catch (ClassNotFoundException cnfe) {
        System.out.println("Didn't find the Rectangle class");
    }

    System.out.println("Fields in Rectangle are:");
    for (int i = 0; i < rectField.length; i++) {
        System.out.println(rectField[i].toString());
    }
}

From source file:DataInserter.java

public static void main(String args[]) throws Exception {
    Class.forName("sun.jdbc.odbc.JdbcOdbcDriver");
    DriverManager.registerDriver(new JdbcOdbcDriver());
    String SQLCommand = "INSERT INTO CONTACT_INFO " + "(First_Name,MI,Last_Name,Street,City,State,Zip) "
            + "VALUES " + "('Michael','J','Corleone','86 Horsehead Blvd','NY','NY','12345');";
    String url = "jdbc:odbc:Contacts";
    Connection con = DriverManager.getConnection(url);
    Statement stmt = con.createStatement();
    stmt.execute(SQLCommand);//from   w  w w.j a  va 2 s.c  o  m
    con.close();

}

From source file:Main.java

public static void main(String[] argv) throws Exception {
    String driver = "com.mysql.jdbc.Driver";

    Class.forName(driver);
    Connection con = DriverManager.getConnection("jdbc:mysql://localhost:3306/jdbctutorial", "root", "root");

    Statement st = con.createStatement();
    int val = st.executeUpdate("INSERT employee VALUES(" + 13 + "," + "'Aman'" + ")");
    System.out.println("1 row affected");

}