In Java 8 joining() method of Collectors Class is used to join various elements of a character or string array into a single string object.
package com.javatutsworld.stream;
import java.util.ArrayList;
import java.util.List;
import java.util.Map;
import java.util.function.Function;
import java.util.stream.Collectors;
public class Java8Join {
public static void main(String args[]) {
List<AccountDetails> acctDetailsList = new ArrayList();
acctDetailsList.add(new AccountDetails("Saaim", "00266767", 2000));
acctDetailsList.add(new AccountDetails("Saaim", "00266767", 2000));
acctDetailsList.add(new AccountDetails("Saaim", "00266767", 2000));
acctDetailsList.add(new AccountDetails("Sudhir", "00266788", 30000));
acctDetailsList.add(new AccountDetails("Gaurav", "00266798", 30000));
acctDetailsList.add(new AccountDetails("Gaurav", "00266798", 90000));
acctDetailsList.add(new AccountDetails("Ram", "00266799", 50000));
acctDetailsList.add(new AccountDetails("Ram", "00266799", 50000));
acctDetailsList.add(new AccountDetails("Ram", "00266799", 2000));
String joinName = acctDetailsList.stream().map(x -> x.getName())
.collect(Collectors.joining(", ", "[", "]"));
System.out.println(joinName);
String joinName1 = acctDetailsList.stream().map(x -> x.getName())
.collect(Collectors.joining(" | ", "[", "]"));
System.out.println(joinName1);
}
}
package com.javatutsworld.stream;
public class AccountDetails {
private String name;
private String accountNumber;
private Integer amount;
public AccountDetails(String name, String accountNumber, Integer amount) {
super();
this.name = name;
this.accountNumber = accountNumber;
this.amount = amount;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public String getAccountNumber() {
return accountNumber;
}
public void setAccountNumber(String accountNumber) {
this.accountNumber = accountNumber;
}
public Integer getAmount() {
return amount;
}
public void setAmount(Integer amount) {
this.amount = amount;
}
}
Output:
[Saaim, Saaim, Saaim, Sudhir, Gaurav, Gaurav, Ram, Ram, Ram]
[Saaim | Saaim | Saaim | Sudhir | Gaurav | Gaurav | Ram | Ram | Ram]