ScraperAPI — Java SDK Best Practices

Requires: Java 8+, Maven or Gradle, SCRAPERAPI_API_KEY environment variable.

Setup

Maven

<dependency>
  <groupId>com.scraperapi</groupId>
  <artifactId>sdk</artifactId>
  <version>1.2</version>
</dependency>

Gradle

implementation 'com.scraperapi:sdk:1.2'

Client instantiation

import com.scraperapi.ScraperApiClient;

ScraperApiClient client = new ScraperApiClient(System.getenv("SCRAPERAPI_API_KEY"));

Never hardcode the API key. Read it from the environment every time.

Basic Usage

The Java SDK uses a fluent builder pattern. Chain parameter methods onto the result of .get(), then call .result() to block and retrieve the HTML.

// Simple GET — returns HTML as a String
String html = client.get("https://example.com/").result();

// With parameters — chain before .result()
String html = client.get("https://example.com/")
    .render(true)
    .result();

// Multiple parameters
String html = client.get("https://example.com/")
    .render(true)
    .countryCode("us")
    .result();

Decision Guide

Parameter Reference

Rendering

// Render JavaScript before returning HTML
// Use when: page is a React/Vue/Angular SPA, or initial scrape returns empty content
// Cost: +10 credits
String html = client.get("https://spa-site.com/").render(true).result();

// Wait for a DOM element before capturing (requires render)
String html = client.get("https://spa-site.com/")
    .render(true)
    .waitForSelector(".product-list")
    .result();

Don't call .render(true) by default — try without it first. It adds cost and latency.

Proxies and Geotargeting

// Route through a country-specific proxy — no extra credit cost
String html = client.get("https://example.com/").countryCode("gb").result();

// Premium residential/mobile IPs — for sites that block datacenter proxies
// Cost: 10 credits (25 with render)
String html = client.get("https://hard-site.com/").premium(true).result();

// Ultra-premium — for the toughest anti-bot protections
// Cost: 30 credits (75 with render)
// Note: incompatible with custom headers
String html = client.get("https://hardest-site.com/").ultraPremium(true).result();

premium and ultraPremium are mutually exclusive — never chain both. Escalation order: standard (1 cr) → render (10 cr) → premium (10 cr) → ultraPremium (30 cr).

Sessions (Sticky Proxy)

// Reuse the same proxy IP across requests — useful for pagination and multi-step flows
// Sessions expire 15 minutes after last use; any integer is a valid ID
String page1 = client.get("https://example.com/page1").sessionNumber(42).result();
String page2 = client.get("https://example.com/page2").sessionNumber(42).result();

Device Type and Autoparse

// Emulate a mobile browser user-agent
String html = client.get("https://example.com/").deviceType("mobile").result();

// Return structured JSON for supported sites (Amazon, Google, etc.)
String json = client.get("https://amazon.com/dp/B09V3KXJPB").autoparse(true).result();

Retry

// Override the default retry count (default: 3)
// ScraperAPI retries failed requests for up to 70 seconds internally;
// .retry() controls how many times the SDK retries after a non-200 response
String html = client.get("https://flaky-site.com/").retry(5).result();

Do not set very low timeouts — the SDK defaults are calibrated to allow ScraperAPI's internal retry window (up to 70 seconds). Setting a 5-second client timeout will cause false failures.

Escalation Ladder

Always start cheapest. Escalate only when the site blocks the previous tier.

public static String scrapeWithEscalation(ScraperApiClient client, String url) throws Exception {
    // Try each tier in order — stop at the first success
    String[][] tiers = {
        {},                                  // 1 credit — standard
        {"render:true"},                     // 10 credits
        {"premium:true"},                    // 10 credits
        {"premium:true", "render:true"},     // 25 credits
        {"ultraPremium:true"},               // 30 credits
    };

    // Practical implementation — explicit tier cascade
    String[] attempts = { "standard", "render", "premium", "premiumRender", "ultraPremium" };
    for (String tier : attempts) {
        try {
            var req = client.get(url);
            switch (tier) {
                case "render":       req = req.render(true); break;
                case "premium":      req = req.premium(true); break;
                case "premiumRender": req = req.premium(true).render(true); break;
                case "ultraPremium": req = req.ultraPremium(true); break;
            }
            String html = req.result();
            if (html != null && html.toLowerCase().contains("<html")) return html;
        } catch (Exception e) {
            // Log and try next tier
        }
    }
    return null;
}

Async Jobs (for Batches)

.result() blocks the calling thread. For 20+ URLs, submit async jobs via the REST endpoint and collect results concurrently.

import java.net.http.*;
import java.net.URI;
import com.fasterxml.jackson.databind.ObjectMapper;

private static final String API_KEY = System.getenv("SCRAPERAPI_API_KEY");
private static final HttpClient HTTP = HttpClient.newHttpClient();
private static final ObjectMapper JSON = new ObjectMapper();

public static Map<String, Object> submitJob(String url) throws Exception {
    String body = JSON.writeValueAsString(Map.of("apiKey", API_KEY, "url", url));
    HttpRequest req = HttpRequest.newBuilder()
        .uri(URI.create("https://async.scraperapi.com/jobs"))
        .POST(HttpRequest.BodyPublishers.ofString(body))
        .header("Content-Type", "application/json")
        .build();
    HttpResponse<String> resp = HTTP.send(req, HttpResponse.BodyHandlers.ofString());
    return JSON.readValue(resp.body(), Map.class); // {id, statusUrl}
}

public static String pollJob(Map<String, Object> job, int maxWaitSec) throws Exception {
    long deadline = System.currentTimeMillis() + maxWaitSec * 1000L;
    while (System.currentTimeMillis() < deadline) {
        HttpRequest req = HttpRequest.newBuilder()
            .uri(URI.create((String) job.get("statusUrl")))
            .GET().build();
        Map<String, Object> data = JSON.readValue(
            HTTP.send(req, HttpResponse.BodyHandlers.ofString()).body(), Map.class);
        if ("finished".equals(data.get("status")))
            return ((Map<?, ?>) data.get("response")).get("body").toString();
        if ("failed".equals(data.get("status")))
            throw new RuntimeException("Job " + job.get("id") + " failed");
        Thread.sleep(5_000);
    }
    throw new RuntimeException("Job " + job.get("id") + " timed out");
}

Structured Data Endpoints

For supported platforms, use structured endpoints instead of raw HTML scraping.

public static String structuredGet(String vertical, Map<String, String> params) throws Exception {
    StringBuilder query = new StringBuilder("api_key=" + API_KEY);
    params.forEach((k, v) -> query.append("&").append(k).append("=").append(v));
    URI uri = URI.create("https://api.scraperapi.com/structured/" + vertical + "?" + query);
    HttpRequest req = HttpRequest.newBuilder().uri(uri).GET().build();
    HttpResponse<String> resp = HTTP.send(req, HttpResponse.BodyHandlers.ofString());
    if (resp.statusCode() != 200)
        throw new RuntimeException("Error " + resp.statusCode());
    return resp.body();
}

// Google SERP
String serp = structuredGet("google/search", Map.of("query", "java web scraping"));

// Amazon product
String product = structuredGet("amazon/product", Map.of("asin", "B09V3KXJPB"));

// Walmart search
String items = structuredGet("walmart/search", Map.of("query", "standing desk", "tld", "com"));

Error Handling

public static String safeScrape(ScraperApiClient client, String url) {
    try {
        return client.get(url).retry(3).result();
    } catch (Exception e) {
        String msg = e.getMessage() != null ? e.getMessage() : "";
        if (msg.contains("401")) throw new RuntimeException("Invalid API key — check SCRAPERAPI_API_KEY", e);
        if (msg.contains("403")) throw new RuntimeException("Blocked or out of credits — try premium/ultraPremium", e);
        if (msg.contains("429")) throw new RuntimeException("Rate limit — reduce concurrency or use async", e);
        if (msg.contains("500") || msg.contains("503"))
            throw new RuntimeException("Transient error — retry with backoff", e);
        throw new RuntimeException("Scrape failed: " + url, e);
    }
}

Status codes: 200 success, 401 bad key, 403 blocked/no credits, 404 target not found, 429 rate limit, 500/503 transient (not charged — safe to retry with backoff).

Credit Cost Reference

Documentation

• Java SDK getting started
• SDK method reference
• JavaScript rendering
• Premium proxy pools
• Autoparse / JSON response
• Callbacks (async)
• Dashboard & credits