现代 Java 的开放底座

// opencode-base-core
import cloud.opencode.base.core.*;

User u = OpenObject.defaultIfNull(user, fallback);
int n  = Convert.toInt("42", 0);
Pair<String, Integer> p = Pair.of("age", 18);
Preconditions.checkArgument(age >= 0, "age >= 0");

// opencode-base-string
import cloud.opencode.base.string.*;

String camel = OpenNaming.toCamel("user_name");      // userName
double sim   = Similarity.jaroWinkler("Leon", "Leo");// 0.96
String safe  = OpenMask.phone("13800138000");        // 138****8000
boolean ok   = OpenVerify.email("a@b.com");

// opencode-base-date
import cloud.opencode.base.date.OpenDate;

LocalDateTime t = OpenDate.parse("2026-04-26 10:00");
String rel = OpenDate.relative(t);                   // "2 hours ago"
boolean wd = OpenDate.isWorkday(LocalDate.now());
int q      = OpenDate.quarterOf(LocalDate.now());

// opencode-base-io
import cloud.opencode.base.io.OpenIO;

String txt = OpenIO.readString("notes.md");
OpenIO.writeString("out.md", txt);
OpenIO.watch("/tmp", e -> log.info(e.toString()));
OpenIO.chunked("big.csv", 8192, this::process);

// opencode-base-i18n
import cloud.opencode.base.i18n.OpenI18n;

OpenI18n.locale(Locale.SIMPLIFIED_CHINESE);
String hi  = OpenI18n.t("greeting.hello", "Leon");   // 你好,Leon
String err = OpenI18n.t("error.notfound");
OpenI18n.reload();

// opencode-base-crypto
import cloud.opencode.base.crypto.OpenCrypto;

byte[] key  = OpenCrypto.aes().keyGen(256);
byte[] enc  = OpenCrypto.aes().gcm(key).encrypt("hello".getBytes());
String hash = OpenCrypto.argon2().hash("password");
String jwt  = OpenCrypto.jwt().sign(claims, secret);

// opencode-base-cache
import cloud.opencode.base.cache.OpenCache;

Cache<String, User> c = OpenCache.lfu()
    .maxSize(10_000)
    .expireAfterWrite(Duration.ofMinutes(10))
    .build();
User u = c.get("u:1", k -> loadUser(k));

// opencode-base-id
import cloud.opencode.base.id.OpenId;

long sf      = OpenId.snowflake().next();
String ulid  = OpenId.ulid().next();
String nano  = OpenId.nano(21).next();
String typed = OpenId.prefixed("user_").ulid().next();

// opencode-base-json
import cloud.opencode.base.json.OpenJson;

record User(String name, int age) {}
String s    = OpenJson.toJson(new User("Leon", 18));
User u      = OpenJson.fromJson(s, User.class);
String name = OpenJson.path(s, "$.name").asString();

// opencode-base-oauth2
import cloud.opencode.base.oauth2.*;

OAuth2Client gh = OAuth2.github(clientId, secret).pkce();
String url      = gh.authorizeUrl("state-xyz");
TokenSet token  = gh.exchangeCode(code);
UserInfo me     = gh.userInfo(token);

// opencode-base-event
import cloud.opencode.base.event.OpenEvent;

OpenEvent.subscribe(OrderPaid.class, e -> ship(e.orderId()));
OpenEvent.publishAsync(new OrderPaid(orderId));      // 虚拟线程
OpenEvent.replay(SagaFailed.class, since);

// opencode-base-captcha
import cloud.opencode.base.captcha.OpenCaptcha;

Captcha c   = OpenCaptcha.numeric().length(6).build();
String text = c.text();                              // "493821"
byte[] png  = c.png();
boolean ok  = c.verify("493821", text);

// opencode-base-image
import cloud.opencode.base.image.OpenImage;

OpenImage.load("photo.jpg")
    .resize(1200, 0)
    .watermark("© OpenCode", Position.BR)
    .toWebP("photo.webp");

// opencode-base-graph
import cloud.opencode.base.graph.OpenGraph;

Graph<String> g = OpenGraph.directed();
g.edge("A", "B", 3); g.edge("B", "C", 5);
List<String> path  = g.dijkstra("A", "C");          // [A, B, C]
List<String> order = g.topoSort();

// opencode-base-pdf
import cloud.opencode.base.pdf.OpenPdf;

OpenPdf.create("invoice.pdf")
    .title("Invoice #2026-001")
    .text("OpenCode.cloud", Font.bold(18))
    .table(rows)
    .save();