如何从Java类调用Unix脚本？JDK中JSch类缺失问题求助

Hey, let's clear this up first: the com.jcraft.jsch classes you're seeing in examples aren't part of any JDK release—they belong to a third-party SSH library called JSch, which is used for remote SSH connections and executing commands on Unix-like systems. That's why you can't find them in JDK 8 or any other JDK version. Here's how to fix this:

1. 引入JSch第三方库 #

Since JSch isn't bundled with the JDK, you need to explicitly add it to your project:

For Maven users: #

Add this dependency to your pom.xml:

<dependency>
    <groupId>com.jcraft</groupId>
    <artifactId>jsch</artifactId>
    <version>0.1.55</version> <!-- Use the latest stable version available -->
</dependency>

For Gradle users: #

Add this line to your build.gradle dependencies block:

implementation 'com.jcraft:jsch:0.1.55'

Manual Jar installation: #

Download the JSch jar file from the Maven Central Repository, then add it to your project's classpath (e.g., in Eclipse: right-click project → Build Path → Add External Archives; in IntelliJ: Project Structure → Libraries → Add the jar).

2. Example: Execute a remote Unix script with JSch #

Here's a basic working example to connect to a remote Unix server and run your script:

import com.jcraft.jsch.JSch;
import com.jcraft.jsch.JSchException;
import com.jcraft.jsch.Session;
import com.jcraft.jsch.ChannelExec;
import java.io.InputStream;

public class RemoteScriptRunner {
    public static void main(String[] args) {
        String remoteHost = "your-server-ip-or-hostname";
        String username = "your-ssh-username";
        String password = "your-ssh-password";
        String scriptPath = "/home/user/scripts/your-script.sh";

        JSch jsch = new JSch();
        Session session = null;
        ChannelExec execChannel = null;

        try {
            // Create SSH session
            session = jsch.getSession(username, remoteHost, 22);
            session.setPassword(password);

            // Skip host key verification (not recommended for production; use proper key auth instead)
            java.util.Properties config = new java.util.Properties();
            config.put("StrictHostKeyChecking", "no");
            session.setConfig(config);

            // Connect to the server
            session.connect();

            // Open an exec channel to run the script
            execChannel = (ChannelExec) session.openChannel("exec");
            execChannel.setCommand("bash " + scriptPath);

            // Capture script output
            InputStream outputStream = execChannel.getInputStream();
            execChannel.connect();

            // Read and print the output
            byte[] buffer = new byte[1024];
            int bytesRead;
            while ((bytesRead = outputStream.read(buffer)) != -1) {
                System.out.print(new String(buffer, 0, bytesRead));
            }

            // Wait for the script to finish
            while (!execChannel.isClosed()) {
                Thread.sleep(100);
            }

            // Print exit status of the script
            System.out.println("\nScript exit status: " + execChannel.getExitStatus());

        } catch (JSchException | InterruptedException | java.io.IOException e) {
            e.printStackTrace();
        } finally {
            // Clean up resources
            if (execChannel != null && execChannel.isConnected()) {
                execChannel.disconnect();
            }
            if (session != null && session.isConnected()) {
                session.disconnect();
            }
        }
    }
}

3. Alternative: Execute a local Unix script (no remote needed) #

If your script runs on the same machine as your Java application, you don't need JSch at all—use JDK's built-in ProcessBuilder instead:

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;

public class LocalScriptRunner {
    public static void main(String[] args) {
        String localScriptPath = "/home/user/scripts/your-local-script.sh";

        ProcessBuilder processBuilder = new ProcessBuilder("bash", localScriptPath);
        processBuilder.redirectErrorStream(true); // Merge stdout and stderr for easier reading

        try {
            Process process = processBuilder.start();

            // Read script output
            BufferedReader reader = new BufferedReader(new InputStreamReader(process.getInputStream()));
            String line;
            while ((line = reader.readLine()) != null) {
                System.out.println(line);
            }

            // Wait for script completion and get exit code
            int exitCode = process.waitFor();
            System.out.println("\nScript exit code: " + exitCode);

        } catch (IOException | InterruptedException e) {
            e.printStackTrace();
        }
    }
}

内容的提问来源于stack exchange，提问作者siddharth sharma