Executing Windows exe file with Java using ProcessBuilder.

WindowsExeFile.java

import java.io.File;
import java.io.UnsupportedEncodingException;
import java.net.URLDecoder;

public class WindowsExeFile {
  
	private final File file;

	public WindowsExeFile(String rawPath) {
		this.file = convertToFile(rawPath);
	}
	
	public String getName() {
		return file.getName();
	}
	public File getDirectory() {
		return file.getParentFile();
	}
	public String getAbsolutePath() {
		return file.getAbsolutePath();
	}
	@Override
	public String toString() {
		return getAbsolutePath();
	}
	
	private File convertToFile(String rawPath) {
		try {
			String decodedPath = URLDecoder.decode(rawPath, "utf-8");
			return new File(decodedPath);
		} catch (UnsupportedEncodingException e) {
			throw new IllegalArgumentException("Não foi possível decodificar o caminho do executável, " + rawPath, e);
		}
	}

}

WindowsExeRunner.java

import java.util.Scanner;

public class WindowsExeRunner {
  
	/**
	 * Executa o arquivo do Windows <code>exeFile</code> sem passar argumentos e
	 * retorna o output de sucesso.
	 */
	public String execute(WindowsExeFile exeFile) {
		Scanner scanner = null;
		try {
			
			Process process = new ProcessBuilder(exeFile.getAbsolutePath())
				.directory(exeFile.getDirectory()) // usa diretório do executável como working directory
				.start();
			process.waitFor();
			
			scanner = new Scanner(process.getInputStream());
			String output = scanner.useDelimiter("\\A").next();
			
			return output;
			
		} catch (Exception e) {
			throw new IllegalStateException("Não foi possível executar o '" + exeFile + "': " + e.getMessage(), e);
		} finally {
			if (scanner != null) {
				scanner.close();
			}
		}
	}
	
}

WindowsExeRunnerTest.java

import static org.junit.Assert.assertEquals;
import org.junit.Before;
import org.junit.Test;

public class WindowsExeRunnerTest {
  
	private static final String WINDOWS_EXE = WindowsExeRunnerTest.class.getResource("Executavel_Windows_de_Teste.exe").getFile();
	
	WindowsExeRunner windowsExeRunner;
	
	@Before
	public void setup() {
		windowsExeRunner = new WindowsExeRunner();
	}
	
	@Test
	public void deveriaExecutarWindowsExe_E_RetornarOutputDeSucesso() {
		
		WindowsExeFile exeFile = new WindowsExeFile(WINDOWS_EXE);
		
		String output = windowsExeRunner.execute(exeFile);
		
		assertEquals("output do executavel", "Teste", output.trim());
	}
	
	@Test(expected=IllegalStateException.class)
	public void deveriaRetornarErroQuandoNaoEncontrarArquivoExecutavel() {
		
		WindowsExeFile invalidExeFile = new WindowsExeFile("invalid_exe_file.exe");
		
		windowsExeRunner.execute(invalidExeFile);
	}

}

https://github.com/caelum/vraptor-console/blob/master/src/main/java/br/com/caelum/vraptor/console/command/Maven.java
https://github.com/caelum/vraptor-console/blob/master/src/main/java/br/com/caelum/vraptor/console/command/RedirectOutput.java