get column values into an array

Question

I have a database table with columns : name, residence, contact. and I want to retrieve only the values in the 'contact column' into an array. the following code is what I wrote:

List l = new ArrayList();
try {
    String sql = "select * from members";
    pst = conn.prepareStatement(sql);
    rs = pst.executeQuery();
    while (rs.next()) {
        String con = rs.getString("Contact");
        l.add(con);
        System.out.println(l);
    }
} catch (Exception e) {
    e.getMessage();
}

but this generates the following result:

[0547615632]
[0547615632, 0246687643]
[0547615632, 0246687643, 0558581764]

whilst I have only 3 records in the table and each having a contact value.
please how do I write the code so that I can get only a single array displaying the result like this:

[0547615632, 0246687643, 0558581764]

thank you very much.

because you print the array on every iteration. either print the array after the loop of only print the current element. shown in the answer below — XtremeBaumer
– XtremeBaumer, Commented Mar 19, 2018 at 12:39

Saif Ahmad · Accepted Answer · 2018-03-19 13:26:03Z

2

You should move the print command out of the while loop:

List l = new ArrayList();
try {
    String sql = "select * from members";
    pst = conn.prepareStatement(sql);
    rs = pst.executeQuery();
    while (rs.next()) {
        String con = rs.getString("Contact");
        l.add(con);
    }
} catch (Exception e) {
    e.getMessage();
}
System.out.println(l);

OR only print the current element in each iteration;

List l = new ArrayList();
try {
    String sql = "select * from members";
    pst = conn.prepareStatement(sql);
    rs = pst.executeQuery();
    while (rs.next()) {
        String con = rs.getString("Contact");
        l.add(con);
        System.out.print(con + " ");
    }
} catch (Exception e) {
    e.getMessage();
}

edited Mar 19, 2018 at 13:26

Saif Ahmad

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answered Mar 19, 2018 at 12:35

Emre Acar

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4 Comments

Rodney Nart Over a year ago

thank you very much @Emre Acer, it worked perfectly. thank you all

Rodney Nart Over a year ago

bro please guide me.. am quite new in stack over flow. please where do I go and what link do I have to click on to accept your answer @EmreAcer

Rodney Nart Over a year ago

I searched through it bro.. I don't think I have earned the privilege to accept an answer. cos I don't see any options available for me to do that. are u on facebook

Emre Acar Over a year ago

@RodneyNart it doesn't require privilege but its ok my friend. Im happy that i solved your problem. Good luck !

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