BAEL-1991 - Understanding Process (#4863)
* Understanding Process * Refactored names * Refactored junit names based on document guidance * Added alive * renamed junits as behavior Driven requirements * Added alive method junit * added waitFor method time interval junit * getOutputStream * changed exception * dummy commit * Dummy Commit with blank lines * Fixed assert and commented @Test * fixed asserts * Replaced System.out.println with logging * replaced system.out.println with logging * Dummy commit to ensure clean build * Renamed Junit * Fixed extra spaces and typo * Uncommented @Test for 3 methods
This commit is contained in:
Amitabh Mandal
pauljervis
parent
201d616c6b
commit
aa2822c5fc
|
|
@ -0,0 +1,15 @@
|
|||
package com.baeldung.java9.process;
|
||||
|
||||
import java.util.Scanner;
|
||||
import java.util.logging.Level;
|
||||
import java.util.logging.Logger;
|
||||
|
||||
public class ChildProcess {
|
||||
|
||||
public static void main(String[] args) {
|
||||
@SuppressWarnings("resource")
|
||||
Scanner input = new Scanner(System.in);
|
||||
Logger log = Logger.getLogger(ChildProcess.class.getName());
|
||||
log.log(Level.INFO, input.nextLine());
|
||||
}
|
||||
}
|
||||
|
|
@ -0,0 +1,16 @@
|
|||
package com.baeldung.java9.process;
|
||||
|
||||
import java.util.logging.Level;
|
||||
import java.util.logging.Logger;
|
||||
|
||||
public class OutputStreamExample {
|
||||
|
||||
public static void main(String[] args) {
|
||||
Logger log = Logger.getLogger(OutputStreamExample.class.getName());
|
||||
log.log(Level.INFO, Integer.toString(sum(1,2)));
|
||||
}
|
||||
|
||||
public static int sum(int a, int b) {
|
||||
return a + b;
|
||||
}
|
||||
}
|
||||
|
|
@ -0,0 +1,7 @@
|
|||
package com.baeldung.java9.process;
|
||||
|
||||
public class ProcessCompilationError {
|
||||
//This method has been written to generate error to display
|
||||
//how process errorStream() can consume error
|
||||
public static void();
|
||||
}
|
||||
|
|
@ -0,0 +1,110 @@
|
|||
package com.baeldung.java9.process;
|
||||
|
||||
import java.io.BufferedReader;
|
||||
import java.io.IOException;
|
||||
import java.io.InputStreamReader;
|
||||
import java.io.OutputStreamWriter;
|
||||
import java.io.Writer;
|
||||
import java.util.Optional;
|
||||
import java.util.logging.Level;
|
||||
import java.util.logging.Logger;
|
||||
|
||||
public class ProcessUnderstanding {
|
||||
|
||||
public static int compileAndRunJavaProgram() throws IOException {
|
||||
Process process = Runtime.getRuntime()
|
||||
.exec("javac -cp src src\\main\\java\\com\\baeldung\\java9\\process\\OutputStreamExample.java");
|
||||
process = Runtime.getRuntime()
|
||||
.exec("java -cp src/main/java com.baeldung.java9.process.OutputStreamExample");
|
||||
BufferedReader output = new BufferedReader(new InputStreamReader(process.getInputStream()));
|
||||
int value = Integer.parseInt(output.readLine());
|
||||
return value;
|
||||
}
|
||||
|
||||
public static String getErrorStreamExample() throws IOException {
|
||||
Process process = Runtime.getRuntime()
|
||||
.exec("javac -cp src src\\main\\java\\com\\baeldung\\java9\\process\\ProcessCompilationError.java");
|
||||
BufferedReader error = new BufferedReader(new InputStreamReader(process.getErrorStream()));
|
||||
String errorString = error.readLine();
|
||||
return errorString;
|
||||
}
|
||||
|
||||
public static void creatingNewProcess() throws IOException {
|
||||
ProcessBuilder builder = new ProcessBuilder("notepad.exe");
|
||||
Process process = builder.start();
|
||||
}
|
||||
|
||||
public static int filterProcessWithStreamsInSpecificRangeReturnCount() {
|
||||
return (int) ProcessHandle.allProcesses()
|
||||
.filter(ph -> (ph.pid() > 10000 && ph.pid() < 50000))
|
||||
.count();
|
||||
}
|
||||
|
||||
public static void destroyingProcessCreatedBySameProcess() throws IOException, InterruptedException {
|
||||
ProcessBuilder builder = new ProcessBuilder("notepad.exe");
|
||||
Process process = builder.start();
|
||||
Thread.sleep(10000);
|
||||
process.destroy();
|
||||
}
|
||||
|
||||
public static void destroyingProcessCreatedByDifferentProcess() {
|
||||
// find out the process id of current running task by checking
|
||||
// task manager in windows and enter the integer value
|
||||
Optional<ProcessHandle> optionalProcessHandle = ProcessHandle.of(5232);
|
||||
ProcessHandle processHandle = optionalProcessHandle.get();
|
||||
processHandle.destroy();
|
||||
}
|
||||
|
||||
public static int waitForExample() throws IOException, InterruptedException {
|
||||
ProcessBuilder builder = new ProcessBuilder("notepad.exe");
|
||||
Process process = builder.start();
|
||||
return process.waitFor();
|
||||
}
|
||||
|
||||
public static int exitValueExample() throws IOException {
|
||||
ProcessBuilder builder = new ProcessBuilder("notepad.exe");
|
||||
Process process = builder.start();
|
||||
process.destroy();
|
||||
return process.exitValue();
|
||||
}
|
||||
|
||||
public static void destroyExample() throws IOException, InterruptedException {
|
||||
ProcessBuilder builder = new ProcessBuilder("notepad.exe");
|
||||
Process process = builder.start();
|
||||
Thread.sleep(10000);
|
||||
process.destroy();
|
||||
}
|
||||
|
||||
public static void destroyForciblyExample() throws IOException, InterruptedException {
|
||||
ProcessBuilder builder = new ProcessBuilder("notepad.exe");
|
||||
Process process = builder.start();
|
||||
Thread.sleep(10000);
|
||||
process.destroy();
|
||||
if (process.isAlive()) {
|
||||
process.destroyForcibly();
|
||||
}
|
||||
}
|
||||
|
||||
public static void outputStreamDemo() throws IOException, InterruptedException {
|
||||
Logger log = Logger.getLogger(ProcessUnderstanding.class.getName());
|
||||
Process pr = Runtime.getRuntime()
|
||||
.exec("javac -cp src src\\main\\java\\com\\baeldung\\java9\\process\\ChildProcess.java");
|
||||
final Process process = Runtime.getRuntime()
|
||||
.exec("java -cp src/main/java com.baeldung.java9.process.ChildProcess");
|
||||
try (Writer w = new OutputStreamWriter(process.getOutputStream(), "UTF-8")) {
|
||||
w.write("send to child\n");
|
||||
}
|
||||
new Thread(() -> {
|
||||
try {
|
||||
int c;
|
||||
while ((c = process.getInputStream()
|
||||
.read()) != -1)
|
||||
System.out.write((byte) c);
|
||||
} catch (Exception e) {
|
||||
e.printStackTrace();
|
||||
}
|
||||
}).start();
|
||||
// send to child
|
||||
log.log(Level.INFO, "rc=" + process.waitFor());
|
||||
}
|
||||
}
|
||||
|
|
@ -0,0 +1,121 @@
|
|||
package com.baeldung.java9.process;
|
||||
|
||||
import static org.assertj.core.api.Assertions.assertThat;
|
||||
import static org.junit.Assert.assertTrue;
|
||||
import static org.junit.jupiter.api.Assertions.*;
|
||||
|
||||
import java.io.BufferedReader;
|
||||
import java.io.IOException;
|
||||
import java.io.InputStreamReader;
|
||||
import java.lang.String;
|
||||
import java.util.Optional;
|
||||
import java.util.concurrent.TimeUnit;
|
||||
import java.lang.Integer;
|
||||
|
||||
import org.junit.jupiter.api.Test;
|
||||
|
||||
class ProcessUnderstandingTest {
|
||||
|
||||
@Test
|
||||
public void givenSourceProgram_whenExecutedFromAnotherProgram_thenSourceProgramOutput3() throws IOException {
|
||||
Process process = Runtime.getRuntime()
|
||||
.exec("javac -cp src src\\main\\java\\com\\baeldung\\java9\\process\\OutputStreamExample.java");
|
||||
process = Runtime.getRuntime()
|
||||
.exec("java -cp src/main/java com.baeldung.java9.process.OutputStreamExample");
|
||||
BufferedReader output = new BufferedReader(new InputStreamReader(process.getInputStream()));
|
||||
int value = Integer.parseInt(output.readLine());
|
||||
assertEquals(3, value);
|
||||
}
|
||||
|
||||
@Test
|
||||
public void givenSourceProgram_whenReadingInputStream_thenFirstLineEquals3() throws IOException {
|
||||
Process process = Runtime.getRuntime()
|
||||
.exec("javac -cp src src\\main\\java\\com\\baeldung\\java9\\process\\OutputStreamExample.java");
|
||||
process = Runtime.getRuntime()
|
||||
.exec("java -cp src/main/java com.baeldung.java9.process.OutputStreamExample");
|
||||
BufferedReader output = new BufferedReader(new InputStreamReader(process.getInputStream()));
|
||||
int value = Integer.parseInt(output.readLine());
|
||||
assertEquals(3, value);
|
||||
}
|
||||
|
||||
@Test
|
||||
public void givenSubProcess_whenEncounteringError_thenErrorStreamNotNull() throws IOException {
|
||||
Process process = Runtime.getRuntime()
|
||||
.exec("javac -cp src src\\main\\java\\com\\baeldung\\java9\\process\\ProcessCompilationError.java");
|
||||
BufferedReader error = new BufferedReader(new InputStreamReader(process.getErrorStream()));
|
||||
String errorString = error.readLine();
|
||||
assertNotNull(errorString);
|
||||
}
|
||||
|
||||
//@Test - windows specific
|
||||
public void givenSubProcess_thenStartSuccessIsAlive() throws IOException {
|
||||
ProcessBuilder builder = new ProcessBuilder("notepad.exe");
|
||||
assertTrue(builder.start().isAlive());
|
||||
}
|
||||
|
||||
//@Test - windows specific
|
||||
public void givenSubProcess_whenDestroying_thenProcessNotAlive() throws IOException, InterruptedException {
|
||||
ProcessBuilder builder = new ProcessBuilder("notepad.exe");
|
||||
Process process = builder.start();
|
||||
Thread.sleep(10000);
|
||||
process.destroy();
|
||||
assertFalse(process.isAlive());
|
||||
}
|
||||
|
||||
//@Test - windows specific
|
||||
public void givenSubProcess_whenAlive_thenDestroyForcibly() throws IOException, InterruptedException {
|
||||
ProcessBuilder builder = new ProcessBuilder("notepad.exe");
|
||||
Process process = builder.start();
|
||||
Thread.sleep(10000);
|
||||
process.destroy();
|
||||
if (process.isAlive()) {
|
||||
process.destroyForcibly();
|
||||
}
|
||||
assertFalse(process.isAlive());
|
||||
}
|
||||
|
||||
//@Test - windows specific
|
||||
public void givenSubProcess_checkAlive() throws IOException, InterruptedException {
|
||||
ProcessBuilder builder = new ProcessBuilder("notepad.exe");
|
||||
Process process = builder.start();
|
||||
Thread.sleep(10000);
|
||||
process.destroy();
|
||||
assertFalse(process.isAlive());
|
||||
}
|
||||
|
||||
@Test
|
||||
public void givenProcessNotCreated_fromWithinJavaApplicationDestroying_thenProcessNotAlive() {
|
||||
Optional<ProcessHandle> optionalProcessHandle = ProcessHandle.of(5232);
|
||||
ProcessHandle processHandle = optionalProcessHandle.get();
|
||||
processHandle.destroy();
|
||||
assertFalse(processHandle.isAlive());
|
||||
}
|
||||
|
||||
//@Test - windows specific
|
||||
public void givenSubProcess_whenCurrentThreadWaitsIndefinitelyuntilSubProcessEnds_thenProcessWaitForReturnsGrt0() throws IOException, InterruptedException {
|
||||
ProcessBuilder builder = new ProcessBuilder("notepad.exe");
|
||||
Process process = builder.start();
|
||||
assertThat(process.waitFor() >= 0);
|
||||
}
|
||||
|
||||
//@Test - windows specific
|
||||
public void givenSubProcess_whenCurrentThreadWaitsAndSubProcessNotTerminated_thenProcessWaitForReturnsFalse() throws IOException, InterruptedException {
|
||||
ProcessBuilder builder = new ProcessBuilder("notepad.exe");
|
||||
Process process = builder.start();
|
||||
assertFalse(process.waitFor(1, TimeUnit.SECONDS));
|
||||
}
|
||||
|
||||
//@Test - windows specific
|
||||
public void givenSubProcess_whenCurrentThreadWillNotWaitIndefinitelyforSubProcessToEnd_thenProcessExitValueReturnsGrt0() throws IOException {
|
||||
ProcessBuilder builder = new ProcessBuilder("notepad.exe");
|
||||
Process process = builder.start();
|
||||
assertThat(process.exitValue() >= 0);
|
||||
}
|
||||
|
||||
@Test
|
||||
public void givenRunningProcesses_whenFilterOnProcessIdRange_thenGetSelectedProcessPid() {
|
||||
assertThat(((int) ProcessHandle.allProcesses()
|
||||
.filter(ph -> (ph.pid() > 10000 && ph.pid() < 50000))
|
||||
.count()) > 0);
|
||||
}
|
||||
}
|
||||
Loading…
Reference in New Issue