Java Implementation

Password Request

import java.io.IOException;
import java.io.InputStream;
import java.net.HttpURLConnection;
import java.net.URL;
import java.util.Scanner;
public class Main {
  public static void main(String[] args) {
    System.out
        .println(jsonGetRequest("https://api.leakedpassword.com/pass/{your-password}"));
  }

  private static String streamToString(InputStream inputStream) {
    String text = new Scanner(inputStream, "UTF-8").useDelimiter("\\Z").next();
    return text;
  }

  public static String jsonGetRequest(String urlQueryString) {
    String json = null;
    try {
      URL url = new URL(urlQueryString);
      HttpURLConnection connection = (HttpURLConnection) url.openConnection();
      connection.setDoOutput(true);
      connection.setInstanceFollowRedirects(false);
      connection.setRequestMethod("GET");
      connection.setRequestProperty("Content-Type", "application/json");
      connection.setRequestProperty("charset", "utf-8");
      connection.connect();
      InputStream inStream = connection.getInputStream();
      json = streamToString(inStream);
    } catch (IOException ex) {
      ex.printStackTrace();
    }
    return json;
  }
}

SHA1 Hash Request

import java.io.IOException;
import java.io.InputStream;
import java.net.HttpURLConnection;
import java.net.URL;
import java.util.Scanner;
public class Main {
  public static void main(String[] args) {
    System.out
        .println(jsonGetRequest("https://api.leakedpassword.com/sha1/{your-sha1-hash}"));
  }

  private static String streamToString(InputStream inputStream) {
    String text = new Scanner(inputStream, "UTF-8").useDelimiter("\\Z").next();
    return text;
  }

  public static String jsonGetRequest(String urlQueryString) {
    String json = null;
    try {
      URL url = new URL(urlQueryString);
      HttpURLConnection connection = (HttpURLConnection) url.openConnection();
      connection.setDoOutput(true);
      connection.setInstanceFollowRedirects(false);
      connection.setRequestMethod("GET");
      connection.setRequestProperty("Content-Type", "application/json");
      connection.setRequestProperty("charset", "utf-8");
      connection.connect();
      InputStream inStream = connection.getInputStream();
      json = streamToString(inStream);
    } catch (IOException ex) {
      ex.printStackTrace();
    }
    return json;
  }
}

Response

{
    "password": {
        "leak": true,
        "hash": "7110eda4d09e062aa5e4a390b0a572ac0d2c0220",
        "seen": 1256907
    }
}