package com.paypal;
import com.paypal.core.PayPalEnvironment;
import com.paypal.core.PayPalHttpClient;
public class Credentials {
    static String clientId = "CLIENT-ID";
    static String secret = "CLIENT-SECRET";
    
    // Creating a sandbox environment
    private static PayPalEnvironment environment = new PayPalEnvironment.Sandbox(clientId, secret);
    
    // Creating a client for the environment
    static PayPalHttpClient client = new PayPalHttpClient(environment);
}

package com.paypal;

import java.io.IOException;
import java.util.ArrayList;
import java.util.List;

import com.paypal.http.HttpResponse;
import com.paypal.http.exceptions.HttpException;
import com.paypal.orders.*;

public class CreateOrderExample {
	public static void main(String[] args) {

		Order order = null;
		// Construct a request object and set desired parameters
		// Here, OrdersCreateRequest() creates a POST request to /v2/checkout/orders
		OrderRequest orderRequest = new OrderRequest();
		orderRequest.intent("CAPTURE");
		List<PurchaseUnitRequest> purchaseUnits = new ArrayList<>();
		purchaseUnits
				.add(new PurchaseUnitRequest().amount(new AmountWithBreakdown().currencyCode("USD").value("100.00")));
		orderRequest.purchaseUnits(purchaseUnits);
		OrdersCreateRequest request = new OrdersCreateRequest().requestBody(orderRequest);

		try {
			// Call API with your client and get a response for your call
			HttpResponse<Order> response = Credentials.client.execute(request);

			// If call returns body in response, you can get the de-serialized version by
			// calling result() on the response
			order = response.result();
			System.out.println("Order ID: " + order.id());
			order.links().forEach(link -> System.out.println(link.rel() + " => " + link.method() + ":" + link.href()));
		} catch (IOException ioe) {
			if (ioe instanceof HttpException) {
				// Something went wrong server-side
				HttpException he = (HttpException) ioe;
				System.out.println(he.getMessage());
				he.headers().forEach(x -> System.out.println(x + " :" + he.headers().header(x)));
			} else {
				// Something went wrong client-side
			}
		}
	}
}

package com.paypal;

import java.io.IOException;

import com.paypal.http.HttpResponse;
import com.paypal.http.exceptions.HttpException;
import com.paypal.orders.*;

public class CaptureOrderExample {
	public static void main(String[] args) {
		Order order = null;
		OrdersCaptureRequest request = new OrdersCaptureRequest("APPROVED-ORDER-ID");

		try {
			// Call API with your client and get a response for your call
			HttpResponse<Order> response = Credentials.client.execute(request);

			// If call returns body in response, you can get the de-serialized version by
			// calling result() on the response
			order = response.result();
			System.out.println("Capture ID: " + order.purchaseUnits().get(0).payments().captures().get(0).id());
			order.purchaseUnits().get(0).payments().captures().get(0).links()
					.forEach(link -> System.out.println(link.rel() + " => " + link.method() + ":" + link.href()));
		} catch (IOException ioe) {
			if (ioe instanceof HttpException) {
				// Something went wrong server-side
				HttpException he = (HttpException) ioe;
				System.out.println(he.getMessage());
				he.headers().forEach(x -> System.out.println(x + " :" + he.headers().header(x)));
			} else {
				// Something went wrong client-side
			}
		}
	}
}