# Class: com.pnfsoftware.jeb.util.concurrent.ProcessExec A helpful class to safely execute short commands, in a blocking or non\-blocking way with or without a timeout, and retrieve the exit code and generated output\(s\) as byte arrays. A lower\-level alternative that offers access to the streams \(including stdin\) is [ProcessWrapper](ProcessWrapper). ## Constructor: ProcessExec Description: Create an object that will execute commands in blocking mode, without timeout. ## Constructor: ProcessExec - parameter: `timeoutMs`, type: `long` - parameter: `redirectErrToOut`, type: `boolean` Description: Create an object that will execute commands. parameter: timeoutMs: timeout for the command execution, in milliseconds: - zero: blocking, without timeout - - positive value: blocking, and target will be killed when timeout has elapsed - - negative value: non\-blocking, [execute](#execute(String...)) returns true immediately; subsequent calls to [#getOutput()](#getOutput()) return null - parameter: redirectErrToOut: if true, the error stream will be redirected to the output stream; this flag is disregarded if the timeout is negative ## Method: execute - parameter: `cmdlist`, type: `java.util.Collection` - return type: `boolean` Description: Execute a command. The method may block, depending on the timeout value provided to the constructor. parameter: cmdlist: the command tokens \(command and arguments\), eg: `["ls", "-l", "*.java"]` return: true in non\-blocking mode or if execution completed, false otherwise ## Method: execute - parameter: `cmdarray`, type: `java.lang.String[]` - return type: `boolean` Description: Execute a command. The method may block, depending on the timeout value provided to the constructor. parameter: cmdarray: the command tokens \(command and arguments\), eg: `["ls", "-l", "*.java"]` return: true in non\-blocking mode or if execution completed, false otherwise ## Method: getError - return type: `byte[]` Description: Retrieve the command execution's error bytes, if execution completed. Never available in non\-blocking mode. return: the bytes or null ## Method: getExitValue - return type: `java.lang.Integer` Description: Retrieve the command execution's exit value, if execution completed. Never available in non\-blocking mode. return: the exit value or null ## Method: getOutput - return type: `byte[]` Description: Retrieve the command execution's output bytes, if execution completed. Never available in non\-blocking mode. return: the bytes or null