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How to use printFlag method of sun.tools.attach.HotSpotVirtualMachine class
Best Powermock code snippet using sun.tools.attach.HotSpotVirtualMachine.printFlag
Source:AttachSetGetFlag.java 
...22 */23/*24 * @test25 * @bug 805482326 * @summary Tests the setFlag and printFlag attach command27 * @library /testlibrary28 * @modules java.base/sun.misc29 * java.compiler30 * java.management31 * jdk.attach/sun.tools.attach32 * jdk.jvmstat/sun.jvmstat.monitor33 * @build com.oracle.java.testlibrary.* AttachSetGetFlag34 * @run driver AttachSetGetFlag35 */36import java.io.BufferedReader;37import java.io.InputStreamReader;38import java.io.InputStream;39import java.lang.reflect.Field;40import java.nio.file.Files;41import java.nio.file.Path;42import java.nio.file.Paths;43import sun.tools.attach.HotSpotVirtualMachine;44import com.oracle.java.testlibrary.Asserts;45import com.oracle.java.testlibrary.Platform;46import com.oracle.java.testlibrary.ProcessTools;47import com.sun.tools.attach.VirtualMachine;48public class AttachSetGetFlag {49 public static void main(String... args) throws Exception {50 // Test a manageable uintx flag.51 testGetFlag("MaxHeapFreeRatio", "60");52 testSetFlag("MaxHeapFreeRatio", "50", "60");53 // Test a non-manageable size_t flag.54 // Since it is not manageable, we can't test the setFlag functionality.55 testGetFlag("ArrayAllocatorMallocLimit", "128");56 // testSetFlag("ArrayAllocatorMallocLimit", "64", "128");57 }58 public static ProcessBuilder runTarget(String flagName, String flagValue) throws Exception {59 return ProcessTools.createJavaProcessBuilder(60 "-XX:+UnlockExperimentalVMOptions",61 "-XX:" + flagName + "=" + flagValue,62 "AttachSetGetFlag$Target");63 }64 public static void testGetFlag(String flagName, String flagValue) throws Exception {65 ProcessBuilder pb = runTarget(flagName, flagValue);66 Process target = pb.start();67 try {68 waitForReady(target);69 int pid = (int)target.getPid();70 HotSpotVirtualMachine vm = (HotSpotVirtualMachine)VirtualMachine.attach(((Integer)pid).toString());71 // Test Get72 BufferedReader remoteDataReader = new BufferedReader(new InputStreamReader(73 vm.printFlag(flagName)));74 boolean foundExpectedLine = false;75 String line = null;76 while((line = remoteDataReader.readLine()) != null) {77 System.out.println("printFlag: " + line);78 if (line.equals("-XX:" + flagName + "=" + flagValue)) {79 foundExpectedLine = true;80 }81 }82 Asserts.assertTrue(foundExpectedLine, "Didn't get the expected output: '-XX:" + flagName + "=" + flagValue + "'");83 vm.detach();84 }85 finally {86 target.destroy();87 target.waitFor();88 }89 }90 public static void testSetFlag(String flagName, String initialFlagValue, String flagValue) throws Exception {91 ProcessBuilder pb = runTarget(flagName, initialFlagValue);92 Process target = pb.start();93 try {94 waitForReady(target);95 int pid = (int)target.getPid();96 HotSpotVirtualMachine vm = (HotSpotVirtualMachine)VirtualMachine.attach(((Integer)pid).toString());97 // First set the value.98 BufferedReader remoteDataReader = new BufferedReader(new InputStreamReader(99 vm.setFlag(flagName, flagValue)));100 String line;101 while((line = remoteDataReader.readLine()) != null) {102 System.out.println("setFlag: " + line);103 // Just empty the stream.104 }105 remoteDataReader.close();106 // Then read and make sure we get back the set value.107 remoteDataReader = new BufferedReader(new InputStreamReader(vm.printFlag(flagName)));108 boolean foundExpectedLine = false;109 line = null;110 while((line = remoteDataReader.readLine()) != null) {111 System.out.println("getFlag: " + line);112 if (line.equals("-XX:" + flagName + "=" + flagValue)) {113 foundExpectedLine = true;114 }115 }116 Asserts.assertTrue(foundExpectedLine, "Didn't get the expected output: '-XX:" + flagName + "=" + flagValue + "'");117 vm.detach();118 } finally {119 target.destroy();120 target.waitFor();121 }...
Source:AttachModelImpl.java
...79 }80 return null;81 }82 83 public synchronized String printFlag(String name) {84 try {85 InputStream in = getVirtualMachine().printFlag(name);86 return readToEOF(in);87 } catch (IOException ex) {88 LOGGER.log(Level.INFO,"printFlag",ex); // NOI18N89 }90 return null;91 }92 93 public synchronized void setFlag(String name, String value) {94 try {95 InputStream in = getVirtualMachine().setFlag(name,value);96 String out = readToEOF(in);97 if (out.length()>0) {98 LOGGER.log(Level.INFO,"setFlag",out); // NOI18N99 }100 } catch (IOException ex) {101 LOGGER.log(Level.INFO,"setFlag",ex); // NOI18N102 }...
Source:CommandExecutor.java
...27 case "jcmd":28 inputStream = hotSpotVirtualMachine.executeJCmd(command);29 break;30 case "printflag":31// inputStream = hotSpotVirtualMachine.printFlag(cmd);32 break;33 //jmap -histoææ34 case "inspectheap":35// inputStream = hotSpotVirtualMachine.heapHisto("-live");36 break;37 //jstackææ38 case "threadDump":39 inputStream = hotSpotVirtualMachine.remoteDataDump(new String[0]);40 break;41 default:42 break;43 }44 return inputStream == null ? "Command unsupported" : readVmOutput(inputStream);45 } catch (Exception e) {...
printFlag
Using AI Code Generation
1import sun.tools.attach.HotSpotVirtualMachine;2import com.sun.tools.attach.VirtualMachine;3import java.io.IOException;4import java.lang.management.ManagementFactory;5import java.lang.management.RuntimeMXBean;6import java.util.List;7import java.util.Properties;8public class 4 {9 public static void main(String[] args) throws Exception {10 String pid = getPID();11 HotSpotVirtualMachine vm = (HotSpotVirtualMachine) VirtualMachine.attach(pid);12 vm.printFlag("PrintGC");13 vm.detach();14 }15 private static String getPID() {16 RuntimeMXBean runtimeMXBean = ManagementFactory.getRuntimeMXBean();17 String jvmName = runtimeMXBean.getName();18 int index = jvmName.indexOf("@");19 if (index < 1) {20 return null;21 }22 return jvmName.substring(0, index);23 }24}
printFlag
Using AI Code Generation
1import java.io.*;2import java.lang.reflect.*;3import sun.tools.attach.*;4public class 4 {5 public static void main(String[] args) throws Exception {6 HotSpotVirtualMachine vm = (HotSpotVirtualMachine) VirtualMachine.attach("1234");7 Class cl = Class.forName("sun.tools.attach.HotSpotVirtualMachine");8 Method m = cl.getDeclaredMethod("printFlag", String.class, PrintStream.class);9 m.setAccessible(true);10 m.invoke(vm, "PrintGCDetails", System.out);11 }12}13import java.io.*;14import java.lang.reflect.*;15import sun.tools.attach.*;16public class 5 {17 public static void main(String[] args) throws Exception {18 HotSpotVirtualMachine vm = (HotSpotVirtualMachine) VirtualMachine.attach("1234");19 Class cl = Class.forName("sun.tools.attach.HotSpotVirtualMachine");20 Method m = cl.getDeclaredMethod("printFlags", PrintStream.class);21 m.setAccessible(true);22 m.invoke(vm, System.out);23 }24}25import java.io.*;26import java.lang.reflect.*;27import sun.tools.attach.*;28public class 6 {29 public static void main(String[] args) throws Exception {30 HotSpotVirtualMachine vm = (HotSpotVirtualMachine) VirtualMachine.attach("1234");31 Class cl = Class.forName("sun.tools.attach.HotSpotVirtualMachine");32 Method m = cl.getDeclaredMethod("printStringFlag", String.class, PrintStream.class);33 m.setAccessible(true);34 m.invoke(vm, "PrintGCDetails", System.out);35 }36}37import java.io.*;38import java.lang.reflect.*;39import sun.tools.attach.*;40public class 7 {41 public static void main(String[] args) throws Exception {42 HotSpotVirtualMachine vm = (HotSpotVirtualMachine) VirtualMachine.attach("1234");43 Class cl = Class.forName("sun.tools.attach.HotSpotVirtualMachine");44 Method m = cl.getDeclaredMethod("printVmArgs", PrintStream.class);45 m.setAccessible(true);46 m.invoke(vm, System.out);47 }48}
printFlag
Using AI Code Generation
1import sun.tools.attach.HotSpotVirtualMachine;2import com.sun.tools.attach.VirtualMachine;3import com.sun.tools.attach.VirtualMachineDescriptor;4import java.io.IOException;5import java.util.List;6public class 4 {7public static void main(String[] args) throws IOException {8List<VirtualMachineDescriptor> vmds = VirtualMachine.list();9VirtualMachineDescriptor vmd = vmds.get(0);10VirtualMachine vm = VirtualMachine.attach(vmd);11HotSpotVirtualMachine hvm = (HotSpotVirtualMachine)vm;12String flagValue = hvm.printFlag("PrintGCDetails");13System.out.println(flagValue);14vm.detach();15}16}
printFlag
Using AI Code Generation
1import java.io.IOException;2import java.util.Properties;3import sun.tools.attach.HotSpotVirtualMachine;4public class 4 {5 public static void main(String[] args) throws IOException {6 HotSpotVirtualMachine vm = new HotSpotVirtualMachine("1234");7 Properties props = vm.getSystemProperties();8 vm.printFlag("PrintGCDetails");9 vm.detach();10 }11}12import java.io.IOException;13import java.util.Properties;14import sun.tools.attach.HotSpotVirtualMachine;15public class 5 {16 public static void main(String[] args) throws IOException {17 HotSpotVirtualMachine vm = new HotSpotVirtualMachine("1234");18 Properties props = vm.getSystemProperties();19 vm.printFlag("PrintGCDetails");20 vm.detach();21 }22}23import java.io.IOException;24import java.util.Properties;25import sun.tools.attach.HotSpotVirtualMachine;26public class 6 {27 public static void main(String[] args) throws IOException {28 HotSpotVirtualMachine vm = new HotSpotVirtualMachine("1234");29 Properties props = vm.getSystemProperties();30 vm.printFlag("PrintGCDetails");31 vm.detach();32 }33}34import java.io.IOException;35import java.util.Properties;36import sun.tools.attach.HotSpotVirtualMachine;37public class 7 {38 public static void main(String[] args) throws IOException {39 HotSpotVirtualMachine vm = new HotSpotVirtualMachine("1234");40 Properties props = vm.getSystemProperties();41 vm.printFlag("PrintGCDetails");42 vm.detach();43 }44}45import java.io.IOException;46import java.util.Properties;47import sun.tools.attach.HotSpot
printFlag
Using AI Code Generation
1import java.io.IOException;2import java.util.List;3import java.util.ArrayList;4import java.util.Arrays;5import com.sun.tools.attach.VirtualMachine;6import com.sun.tools.attach.VirtualMachineDescriptor;7import com.sun.tools.attach.AttachNotSupportedException;8import com.sun.tools.attach.spi.AttachProvider;9import sun.tools.attach.HotSpotVirtualMachine;10public class PrintFlag {11 public static void main(String[] args) throws IOException,12 IllegalArgumentException, InvocationTargetException {13 String flagName = args[0];14 List<VirtualMachineDescriptor> vmdList = VirtualMachine.list();15 for (VirtualMachineDescriptor vmd : vmdList) {16 String command = "jcmd " + vmd.id() + " VM.print_flag " + flagName;17 System.out.println(command);18 Process process = Runtime.getRuntime().exec(command);19 process.waitFor();20 BufferedReader reader = new BufferedReader(new InputStreamReader(process.getInputStream()));21 String line = reader.readLine();22 System.out.println(line);23 reader.close();24 process.destroy();25 }26 }27}
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