message.myMessage=This message is for ${name} in ${location}

message.myMessage = This message is for {0} in {1}

message.myMessage = This message is for {0} in {1}
message.myNameMessage = This message is for {0}
message.myLocationMessage = This message is for people in {1}
message.myAlternateMessage = The message params are location: {1}; name: {0}

message.myMessage = This message is for {0,,name} in {1,,location}

message.myMessage=This message is for {name} in {location}.

MessageFormatPattern:
     String
     MessageFormatPattern FormatElement String

FormatElement:
     { ArgumentIndex }
     { ArgumentIndex , FormatType }
     { ArgumentIndex , FormatType , FormatStyle }

public String format(String message, String... arguments) {
    for (String argument : arguments) {
        String[] keyValue = argument.split("=");
        if (keyValue.length != 2)
            throw new IllegalArgumentException("Incorrect argument: " + argument);
        String placeholder = "${" + keyValue[0] + "}";
        if (!message.contains(placeholder))
            throw new IllegalArgumentException(keyValue[0] + " does not exists.");
        while (message.contains(placeholder))
            message = message.replace(placeholder, keyValue[1]);
    }

    return message;
}

Properties messages = ...
    Map<String, String> m = new HashMap<>();
    m.put("name", "Mithu");
    m.put("location", "Dhaka");
    StrSubstitutor sub = new StrSubstitutor(m);
    String msg = sub.replace(messages.getProperty("message.myMessage"));
    // msg = This message is for Mithu in Dhaka