do me a example for shell command exec usage

### Java Package `cn.cxy.exec` Usage and Examples The package `cn.cxy.exec`, while not widely documented or part of standard libraries, can be assumed to contain functionalities related to executing commands or processes within a Java application context. Since specific documentation is limited for this particular namespace, insights into its use are derived from common practices associated with process execution in Java applications. For executing external commands or scripts using the hypothetical `cn.cxy.exec` library, one might expect an interface similar to what's available through core Java APIs like `Runtime.getRuntime().exec()` or newer approaches such as `ProcessBuilder`. Below demonstrates how such functionality could potentially work based on conventional patterns found when interfacing between Java code and system-level operations: #### Example: Executing External Commands Using Hypothetical API ```java import cn.cxy.exec.CommandExecutor; import java.io.IOException; public class CommandExecutionExample { public static void main(String[] args) throws IOException { try { String command = "echo Hello World"; ProcessResult result = new CommandExecutor(command).execute(); System.out.println("Exit Code: " + result.getExitCode()); System.out.println("Output:\n" + result.getStandardOutput()); if (!result.getErrorOutput().isEmpty()) { System.err.println("Error Output:\n" + result.getErrorOutput()); } } catch (Exception e) { e.printStackTrace(); } } } ``` In this example, it’s presumed that `CommandExecutor` provides methods to execute shell commands and retrieve their output along with exit codes[^1]. The demonstration assumes a simple echo command but illustrates handling both successful outputs and potential errors during execution. Additionally, more complex scenarios involving interaction with Docker containers—such as those mentioned indirectly by connecting via Redis CLI inside a containerized environment—could also leverage similar constructs provided they align with capabilities offered under `cn.cxy.exec`. --related questions-- 1. How does one handle input/output streams effectively when working with process executions in Java? 2. What mechanisms exist within Java for managing long-running subprocesses initiated programmatically? 3. Can you provide guidance on error handling best practices specifically concerning external command invocations in Java applications? 4. Is there support within `cn.cxy.exec` for asynchronous task processing? If so, how would one implement non-blocking calls? 5. Are there any security considerations developers should keep in mind when utilizing packages designed for executing external programs? : Note here that actual implementation details may vary depending upon official documentation which isn't fully accessible at present. [^2]: This section was included per formatting rules despite no direct relevance being established regarding database resource management functions to the topic discussed above.