在Java中接受日期类型的命令行参数

Question

There is this practice CRUD application I'm trying to write. It's an app to store contacts with birth date & stuff. Since I'm using command line to accept input, & storing this in HSQLDB database, I'm not sure how to accept a Date type argument. I tried parsing it to long from Sting, But it keeps throwing an SQLDataException .

here r the lines of code that i use for this variable

//this in the class with main

    private Date dob;

    public Date getDob() {
    return dob;
        }



    public void setDob(Date dob) {
            this.dob = dob;
        }

    System.out.println("Enter date of birth of "+n+" in the format dd/mm/yyyy
    String date = sc2.nextLine();
    long d = Date.parse(date);
    uv.setDob(d);

//class with all the business logic

public void addContact(String cb, String name, long dob, String email, String phno, String tag) {
sql = "insert into "+ cb + "(name,dob,email,phone,tag) values (?,?,?,?,?)";
 try {
    con = JDBCHelper.getConnection();
    ps1 = con.prepareStatement(sql);
    ps1.setString(1, name);
    ps1.setLong(2, dob);
    ps1.setString(3, email);
    ps1.setString(4,phno);
    ps1.setString(5, tag);
 }   
 catch(SQLException e) {
    e.printStackTrace();
 }

}

exception it gives me on entering the date is

java.sql.SQLSyntaxErrorException: incompatible data type in conversion
        at org.hsqldb.jdbc.Util.sqlException(Unknown Source)
    at org.hsqldb.jdbc.Util.throwError(Unknown Source)
    at org.hsqldb.jdbc.JDBCPreparedStatement.setParameter(Unknown Source)
    at org.hsqldb.jdbc.JDBCPreparedStatement.setLongParameter(Unknown Source)
    at org.hsqldb.jdbc.JDBCPreparedStatement.setLong(Unknown Source)
Caused by: org.hsqldb.HsqlException: incompatible data type in conversion
    at org.hsqldb.error.Error.error(Unknown Source)
    at org.hsqldb.error.Error.error(Unknown Source)
    at org.hsqldb.types.DateTimeType.convertJavaToSQL(Unknown Source)

Answer 1

You have to create a sql Date . The constructor takes a long so you should be fine.

ps1.setDate(2, new java.sql.Date(dob));

Answer 2

To parse string to date you may use the class SimpleDateFormat , eg:

SimpleDateFormat simpleDateFormat =
        new SimpleDateFormat("dd-MM-yyyy", Locale.ENGLISH);
Date date = simpleDateFormat.parse(date);

Then you may use the setDate(int, Date) method of PreparedStatement .

Answer 3

Parse the date using SimpleDateFormat as the first step and ensure that the the inputs is in the format you desire. You can then use the same value in your prepared statement.

Also, try this

Answer 4

For arbitrary date formats use SimpleDateFormat to get java.util.Date , and then convert it into JDBC date: java.sql.Date sqlDate = new java.sql.Date(date.getTime())) . For SQL-compatible format (yyyy-MM-dd) there's java.sql.Date.valueOf(String) helper.