14: Add getProgramAccounts(...) API method

src/main/tjava/com/r35157/libs/solana/impl/ref/SolanaBlockChainImpl.tjava

@@ -331,6 +331,67 @@ public class SolanaBlockChainImpl implements SolanaBlockChain {
         );
     }
 
+    @Override
+    public Set<SolanaAccountInfo> getProgramAccounts(
+            ΩSolanaProgramIdΩ programId,
+            Set<SolanaProgramAccountMemcmpFilter> filters
+    ) throws IOException, InterruptedException {
+        String jsonBody = createGetProgramAccountsBody(programId, filters);
+
+        HttpRequest request = HttpRequest.newBuilder()
+                .uri(URI.create(RPC_URL))
+                .header("Content-Type", "application/json")
+                .POST(HttpRequest.BodyPublishers.ofString(jsonBody))
+                .build();
+
+        HttpResponse<String> response = sendThrottled(request);
+
+        if (response.statusCode() != 200) {
+            throw new IOException("RPC call failed: HTTP " + response.statusCode() + "\n" + response.body());
+        }
+
+        JsonNode root = objectMapper.readTree(response.body());
+
+        if (root.has("error")) {
+            throw new IOException("Solana RPC error: " + root.get("error").toPrettyString());
+        }
+
+        JsonNode result = root.path("result");
+
+        if (!result.isArray()) {
+            throw new IOException("getProgramAccounts response did not contain result array!");
+        }
+
+        Set<SolanaAccountInfo> accountInfos = new HashSet<>();
+
+        for (JsonNode accountNode : result) {
+            JsonNode pubkeyNode = accountNode.path("pubkey");
+            JsonNode account = accountNode.path("account");
+
+            if (!pubkeyNode.isTextual()) {
+                throw new IOException("getProgramAccounts response contained account without textual pubkey!");
+            }
+
+            JsonNode ownerNode = account.path("owner");
+            if (!ownerNode.isTextual()) {
+                throw new IOException("getProgramAccounts response contained account without textual owner!");
+            }
+
+            JsonNode dataNode = account.path("data");
+            if (!dataNode.isArray() || dataNode.isEmpty() || !dataNode.get(0).isTextual()) {
+                throw new IOException("getProgramAccounts response contained account without base64 data!");
+            }
+
+            accountInfos.add(new SolanaAccountInfo(
+                    pubkeyNode.asText(),
+                    ownerNode.asText(),
+                    dataNode.get(0).asText()
+            ));
+        }
+
+        return Set.copyOf(accountInfos);
+    }
+
     private synchronized HttpResponse<String> sendThrottled(HttpRequest request) throws IOException, InterruptedException {
         waitBeforeRemoteCall();