Convert String[] to comma separated string in java

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i have one String[]

String[] name = {"amit", "rahul", "surya"};

i want to send name as parameter in sql query inside IN clause so how do i convert into a format

'amit','rahul','surya'
24 Answers

Extention for prior Java 8 solution

String result = String.join(",", name);

If you need prefix or/ and suffix for array values

 StringJoiner joiner = new StringJoiner(",");
 for (CharSequence cs: name) {
     joiner.add("'" + cs + "'");
 }
 return joiner.toString();

Or simple method concept

  public static String genInValues(String delimiter, String prefix, String suffix, String[] name) {
    StringJoiner joiner = new StringJoiner(delimiter);
    for (CharSequence cs: name) {
      joiner.add(prefix + cs + suffix);
    }
    return joiner.toString();
  }

For example

For Oracle i need "id in (1,2,3,4,5)" 
then use genInValues(",", "", "", name);
But for Postgres i need "id in (values (1),(2),(3),(4),(5))"
then use genInValues(",", "(", ")", name);

In java 8 for none string array and none primitive object (Long, Integer, ...)

List<Long> ids = Arrays.asList(1l, 2l,3l);
ids.stream().map(String::valueOf).collect(Collectors.joining(","))))

In java 8 for specific field of an objets array (example a car with 2 fields color and speed)

List<Car> cars= Cars.asList(car1, cars2,car3);
    cars.stream().map(Car::getColor).collect(Collectors.joining(","))))

Combine map with valueOf for none String field of an array of objects

Better rename name to names since its an Array.
Java 8+ solution, taking into :

String[] names = {"amit", "rahul", "surya","O'Neil"};
// For each name:
// single quote with another single quote
// & put single quotes around 
// & add comma at end 
String sql = Stream.<String>of(names)
    .reduce("", (acc,s)-> acc + "'" + s.replaceAll("'","''") + "',")
// Remove last trailing comma
sql = sql.substring(0, sql.length()-1)

This my be helpful!!!

private static String convertArrayToString(String [] strArray) {
            StringBuilder builder = new StringBuilder();
            for(int i = 0; i<= strArray.length-1; i++) {
                if(i == strArray.length-1) {
                    builder.append("'"+strArray[i]+"'");
                }else {
                    builder.append("'"+strArray[i]+"'"+",");
                }
            }
            return builder.toString();
        }
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