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Making a Multipart/Form-Data POST Request in Java

<dependencies> <dependency> <groupId>org.apache.httpcomponents</groupId> <artifactId>httpclient</artifactId> <version>4.4</version> </dependency> <dependency> <groupId>org.apache.httpcomponents</groupId> <artifactId>httpmime</artifactId> <version>4.4</version> </dependency> </dependencies> CloseableHttpClient httpClient = HttpClients.createDefault(); HttpPost uploadFile = new HttpPost("..."); MultipartEntityBuilder builder = MultipartEntityBuilder.create(); builder.addTextBody("field1", "yes", ContentType.TEXT_PLAIN); // This attaches the file to the POST: File f = new File("[/path/to/upload]"); builder.addBinaryBody( "file", new FileInputStream(f), ContentType.APPLICATION_OCTET_STREAM, f.getName() ); HttpEntity multipart = builder.build(); uploadFile.setEntity(multipart); CloseableHttpResponse response = httpClient.execute(uploadFile); HttpEntity responseEntity = response.getEntity(); 4.0 版本需要按照下面...

Direct Invocation of YOLOv8 Trained Models in Java

pom.xml 文件中需要增加一些包。 <repositories> <repository> <id>opencv</id> <url>https://mvnrepository.com/artifact/org.openpnp/opencv</url> </repository> <repository> <id>djl.ai</id> <url>https://oss.sonatype.org/content/repositories/snapshots/</url> </repository> </repositories> <dependencies>  <dependency> <groupId>ai.djl</groupId> <artifactId>api</artifactId> <version>${djl.version}</version> </dependency>  <dependency> <groupId>ai.djl.pytorch</groupId> <artifactId>pytorch-engine</artifactId> <version>${djl.version}</version> </dependency>  <dependency> <groupId>ai.djl.pytorch</groupId> <artifactId>pytorch-model-zoo</artifactId> <version>${djl.version}</version> </dependency>  <dependency> <groupId>ai.djl</groupId> <artifactId>basicdataset</artifactId> <version>${djl.version}</version> </dependency>  <dependency>...

Vector clocks

给定的 Lamport 时间戳 $L(a)$ 和 $L(b)$ 并且 $L(a) < L(b)$，我们推断不出 $a \rightarrow b$ 或者 $a || b$.1 要区分平行的这些事件，需要 vertor clocks: 假定分布式系统中有 $n$ 个节点，\(N = \langle N_{1},...

FIFO broadcast

Definition 最弱的广播类型称为先进先出（FIFO）广播。在这个模型中，由同一节点发送的信息按照发送的顺序传递。例如下图中，$m_{1}$ 必须在 $m_{3}$ 之...

Total order broadcast

Definition 总秩序广播（total order broadcast），有时也被称为原子广播（atomic broadcast）。FIFO broadcast 和 Causal broadcast 允许不同的节点以不同...

Distribution System

Remote Procedure Call Remote Procedure Call (RPC) 使得调用远程函数就像调用本地函数一样，这样就不需要关心资源的具体问题，实际上 RPC 是将方法调用转换成了网络通信。但是遇到通信失败怎...

Causality and Happen-before relation

The Happens-before relation An event is something happening at one node (sending or receiving a message, or a local execution step). event $a$ happens before event $b$, written $a \rightarrow b$. 那么在分布式，有三种情况，满足其中一条，则 $a$ 是发生在 $b$ 之前： $a$ 和 $b$ 发生在相同节...

Causal broadcast

Definition Causal broadcast 算法有点类似于 FIFO broadcast：每条被广播的消息附上的不是一个序列号，而是一个整数的向量。这种算法有时被称为向量时钟算法，向量时钟...

Lamport clocks

Lamport clocks algorithm Lamport clocks in words Figure 1: lamport-example-simple 每个节点都维护一个计数器 $t$，每一个当前节点事件 $e$ 发生时，自增 1。增长后的值设为 $L(e)$ 发送消息时附带上当前的计数 $t$ 消息...

Raft consensus algorithm

Figure 1: node-state-transitions-in-raft 一个节点有三种状态：leader，candidate 和 follower。当一个节点第一次运行，或者崩溃后恢复时，处于 follower 的状态并且等待其...