Postgres jdbc PreparedStatement setObject does not cast values?

I am trying to insert the data onto different databases. Used dbutils to incorporate QueryRunner.batch() for batch inserts. This worked for SQL Server which casts the data to the corresponding type. I tried the same with PostgreSQL but of no avail. I tried a sample insert but that has failed in PostGres which validates my claim whereas the inserts for SQL Server were successful:

private void postGrestest() throws ClassNotFoundException, SQLException
{
    Class.forName("org.postgresql.Driver");

    String dropStmt = "DROP TABLE PUBLIC.TEST";
    String createStmt = "CREATE TABLE PUBLIC.TEST(COL1 VARCHAR(10), COL2 BOOLEAN)";
    String insertStmt = "INSERT INTO PUBLIC.TEST(COL1, COL2) VALUES (?, ?)";
    try (Connection connection = DriverManager.getConnection(
            "jdbc:postgresql://<host>:5432/<dbname>", "<username>", "<password>");
            Statement stmt = connection.createStatement();
            PreparedStatement ps = connection.prepareStatement(insertStmt);)
    {
        //stmt.execute(dropStmt);
        stmt.execute(createStmt);
        Random r = new Random();
        for (int i = 0; i < 100; i++)
        {
            Object str = "Test" + i;
            ps.setObject(1, str);
            Object obj = String.valueOf(r.nextBoolean());
            ps.setObject(2, obj);
            ps.executeUpdate();
        }
    }
}

Exception in thread "main" org.postgresql.util.PSQLException: ERROR: column "col2" is of type boolean but expression is of type character varying Hint: You will need to rewrite or cast the expression.
Position: 49

private void sqlserverTest() throws SQLException, ClassNotFoundException
{
    Class.forName("com.microsoft.sqlserver.jdbc.SQLServerDriver");

    String dropStmt = "DROP TABLE DBO.TEST";
    String createStmt = "CREATE TABLE DBO.TEST(COL1 VARCHAR(10), COL2 BIT)";
    String insertStmt = "INSERT INTO DBO.TEST(COL1, COL2) VALUES (?, ?)";
    try (Connection connection = DriverManager.getConnection(
            "jdbc:sqlserver://<host>:<port>", "<username>", "<password>");
            Statement stmt = connection.createStatement();
            PreparedStatement ps = connection.prepareStatement(insertStmt);)
    {
        //stmt.execute(dropStmt);
        stmt.execute(createStmt);
        Random r = new Random();
        for (int i = 0; i < 100; i++)
        {
            Object str = "Test" + i;
            ps.setObject(1, str);
            Object obj = String.valueOf(r.nextBoolean());
            ps.setObject(2, obj);
            ps.executeUpdate();
        }
    }
}

The reason I have to cast because, I read the data from a file and get as an object array. I do not have idea of the type beforehand and would like to use setObject instead of specific types setBoolean, setInteger, etc.

What other ways that I can use without casting at my application level and let the driver handle the cast?