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iPhone CHow to use our Java Currency Converter
Converting currencies using our PHP Exchange Rate API is as easy as posting a HTTP request. Your requests would need to follow
this simple pattern:
http://www.exchangerate-api.com/FROM_CURRENCY/TO_CURRENCY/AMOUNT?k=YOUR_API_KEY
Here are some examples in Java:
1. Simple Currency Conversion (in Java):
To convert from 12.50 USD (US Dollar) to GBP (British Pound):
try {
URL convert = new URL("http://www.exchangerate-api.com/usd/gbp/12.50?k=API_KEY");
BufferedReader in = new BufferedReader(new InputStreamReader(convert.openStream()));
String answer = in.readLine();
in.close();
}
catch (MalformedURLException mue) {
System.exit(1);
}
catch (IOException ioe) {
System.exit(1);
}
URL convert = new URL("http://www.exchangerate-api.com/usd/gbp/12.50?k=API_KEY");
BufferedReader in = new BufferedReader(new InputStreamReader(convert.openStream()));
String answer = in.readLine();
in.close();
}
catch (MalformedURLException mue) {
System.exit(1);
}
catch (IOException ioe) {
System.exit(1);
}
Or to get how many Japanese Yen (JPY) there are to the South African Rand (ZAR):
try {
URL convert = new URL("http://www.exchangerate-api.com/zar/jpy?k=API_KEY");
BufferedReader in = new BufferedReader(new InputStreamReader(convert.openStream()));
String answer = in.readLine();
in.close();
}
catch (MalformedURLException mue) {
System.exit(1);
}
catch (IOException ioe) {
System.exit(1);
}
URL convert = new URL("http://www.exchangerate-api.com/zar/jpy?k=API_KEY");
BufferedReader in = new BufferedReader(new InputStreamReader(convert.openStream()));
String answer = in.readLine();
in.close();
}
catch (MalformedURLException mue) {
System.exit(1);
}
catch (IOException ioe) {
System.exit(1);
}
Error Codes:
The API returns the following error codes:-1 if an invalid amount is used (must be numeric floating point or integer numbers)
-2 if either of the 3 letter currency codes are invalid (Check our supported currencies)
-3 if an invalid key is used (Get an API key)
-4 if your monthly API query limit is reached (Click here for extended usage)
-5 if an unresolvable IP address is provided (This only applies for our "Automatic Country/Flag Information" query.)
We also offer two additional types of query:
2. Automatic Currency Detection/Conversion (in Java):
To convert from 12.50 USD (US Dollar) to your user's currency:
String ip = request.getRemoteAddr();
String result = "";
try {
URL con = new URL("http://www.exchangerate-api.com/auto/"+ip+"/12.50?k=API_KEY");
BufferedReader in = new BufferedReader(new InputStreamReader(con.openStream()));
result = in.readLine();
in.close();
}
catch (MalformedURLException mue) {
System.exit(1);
}
catch (IOException ioe) {
System.exit(1);
}
if(result != "") {
String[] result_array = result.split("|");
Float converted_amount = array[0]; //FINAL CONVERTED AMOUNT
String symbol_unicode = array[1]; //FINAL DECIMAL UNICODE FOR SYMBOL
String currency_code = array[2]; //FINAL 3-DIGIT CURRENCY CODE (EG: USD)
//If you want to display the currency's symbol in HTML:
String symbol_html = "";
String[] symbol_characters = symbol_html.split(",");
for(int i=0; i < symbol_characters.length; i++) {
symbol_html = symbol_html+"&#"+symbol_characters[i]+";";
}
}
String result = "";
try {
URL con = new URL("http://www.exchangerate-api.com/auto/"+ip+"/12.50?k=API_KEY");
BufferedReader in = new BufferedReader(new InputStreamReader(con.openStream()));
result = in.readLine();
in.close();
}
catch (MalformedURLException mue) {
System.exit(1);
}
catch (IOException ioe) {
System.exit(1);
}
if(result != "") {
String[] result_array = result.split("|");
Float converted_amount = array[0]; //FINAL CONVERTED AMOUNT
String symbol_unicode = array[1]; //FINAL DECIMAL UNICODE FOR SYMBOL
String currency_code = array[2]; //FINAL 3-DIGIT CURRENCY CODE (EG: USD)
//If you want to display the currency's symbol in HTML:
String symbol_html = "";
String[] symbol_characters = symbol_html.split(",");
for(int i=0; i < symbol_characters.length; i++) {
symbol_html = symbol_html+"&#"+symbol_characters[i]+";";
}
}
3. Automatic Country/Flag Information (in Java):
To retrieve your user's national flag and other country information:
String ip = request.getRemoteAddr();
String result = "";
try {
URL con = new URL("http://www.exchangerate-api.com/country_info/"+ip+"?k=API_KEY");
BufferedReader in = new BufferedReader(new InputStreamReader(con.openStream()));
result = in.readLine();
in.close();
}
catch (MalformedURLException mue) {
System.exit(1);
}
catch (IOException ioe) {
System.exit(1);
}
if(result != "") {
String[] result_array = result.split("|"); String country_name = result_array[0]; //FINAL COUNTRY NAME
String country_code_2 = result_array[1]; //FINAL 2-DIGIT COUNTRY CODE (EG: US)
String country_code_3 = result_array[2]; //FINAL 3-DIGIT COUNTRY CODE (EG: USA)
String currency_code = result_array[3]; //FINAL 3-DIGIT CURRENCY CODE (EG: USD)
String symbol_unicode = result_array[4]; //FINAL DECIMAL UNICODE FOR SYMBOL
String flag_url = result_array[5]; //FINAL URL FOR FLAG IMAGE
//If you want to display the currency's symbol in HTML:
String symbol_html = "";
String[] symbol_characters = symbol_html.split(",");
for(int i=0; i < symbol_characters.length; i++) {
symbol_html = symbol_html+"&#"+symbol_characters[i]+";";
}
//If you want to display an image of the flag in HTML:
String flag_image = "<img src='"+flag_url+"' />";
}
String result = "";
try {
URL con = new URL("http://www.exchangerate-api.com/country_info/"+ip+"?k=API_KEY");
BufferedReader in = new BufferedReader(new InputStreamReader(con.openStream()));
result = in.readLine();
in.close();
}
catch (MalformedURLException mue) {
System.exit(1);
}
catch (IOException ioe) {
System.exit(1);
}
if(result != "") {
String[] result_array = result.split("|"); String country_name = result_array[0]; //FINAL COUNTRY NAME
String country_code_2 = result_array[1]; //FINAL 2-DIGIT COUNTRY CODE (EG: US)
String country_code_3 = result_array[2]; //FINAL 3-DIGIT COUNTRY CODE (EG: USA)
String currency_code = result_array[3]; //FINAL 3-DIGIT CURRENCY CODE (EG: USD)
String symbol_unicode = result_array[4]; //FINAL DECIMAL UNICODE FOR SYMBOL
String flag_url = result_array[5]; //FINAL URL FOR FLAG IMAGE
//If you want to display the currency's symbol in HTML:
String symbol_html = "";
String[] symbol_characters = symbol_html.split(",");
for(int i=0; i < symbol_characters.length; i++) {
symbol_html = symbol_html+"&#"+symbol_characters[i]+";";
}
//If you want to display an image of the flag in HTML:
String flag_image = "<img src='"+flag_url+"' />";
}