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How to use loadAgent method of sun.tools.attach.HotSpotVirtualMachine class
Best Powermock code snippet using sun.tools.attach.HotSpotVirtualMachine.loadAgent
Source:JvmSelfAttach.java 
...122 "L" + cnname.replace('.', '/') + ";"123 );124 UA.getUnsafe().defineClass(null, code, 0, code.length, ClassLoader.getSystemClassLoader(), null);125 }126 loadAgent(cnname, EAN, rdfile);127 fetchInst(cnname);128 }129 private static void loadAgent(String cnname, String EAN, File rdfile) throws Throwable {130 String absp = rdfile.getAbsolutePath();131 List<Throwable> allFails = new ArrayList<>();132 try { //java.instrument133 Method met = Class.forName("sun.instrument.InstrumentationImpl")134 .getDeclaredMethod("loadAgent", String.class);135 UA.setAccessible(met, true);136 met.invoke(null, absp);137 return;138 } catch (Throwable e) {139 allFails.add(e);140 }141 long pid;142 String pid_str;143 try {144 Class<?> PH = Class.forName("java.lang.ProcessHandle");145 MethodHandles.Lookup lk = MethodHandles.lookup();146 Object currentProcess = lk.findStatic(PH, "current", MethodType.methodType(PH)).invoke();147 pid = (long) lk.findVirtual(PH, "pid", MethodType.methodType(long.class)).invoke(currentProcess);148 pid_str = Long.toString(pid);149 } catch (Throwable ignored) {150 RuntimeMXBean runtimeMXBean = ManagementFactory.getRuntimeMXBean();151 String name = runtimeMXBean.getName();152 pid_str = name.substring(0, name.indexOf('@'));153 pid = Long.parseLong(pid_str);154 }155 try { // jdk.attach156 System.setProperty("jdk.attach.allowAttachSelf", "true");157 try {158 Class<?> VM = Class.forName("jdk.internal.misc.VM");159 Field f = VM.getDeclaredField("savedProps");160 UA.setAccessible(f, true);161 ((Map) f.get(null)).put("jdk.attach.allowAttachSelf", "true");162 } catch (Throwable a) {163 allFails.add(a);164 }165 try {166 Class<?> HotSpotVirtualMachine = Class.forName("sun.tools.attach.HotSpotVirtualMachine");167 UA.getUnsafe().ensureClassInitialized(HotSpotVirtualMachine);168 Field attach_self = HotSpotVirtualMachine.getDeclaredField("ALLOW_ATTACH_SELF");169 UA.setAccessible(attach_self, true);170 try {171 attach_self.setBoolean(null, true);172 } catch (Throwable w) {173 allFails.add(w);174 Unsafe unsafe = UA.getUnsafe();175 unsafe.putBoolean(176 unsafe.staticFieldBase(attach_self),177 unsafe.staticFieldOffset(attach_self),178 true179 );180 }181 } catch (Throwable a) {182 allFails.add(a);183 }184 VirtualMachine attach = VirtualMachine.attach(pid_str);185 attach.loadAgent(absp);186 attach.detach();187 return;188 } catch (Throwable e) {189 allFails.add(e);190 }191 try {192 File javaHome = new File(System.getProperty("java.home"));193 if (javaHome.getName().equals("jre")) {194 javaHome = javaHome.getParentFile();195 }196 File tools = new File(javaHome, "lib/tools.jar");197 if (tools.exists()) {198 URLClassLoader urlClassLoader = new URLClassLoader(new URL[]{199 tools.toURI().toURL()200 });201 Class<?> vm = urlClassLoader.loadClass("com.sun.tools.attach.VirtualMachine");202 Object attach = vm.getMethod("attach", String.class).invoke(null, pid_str);203 vm.getMethod("loadAgent", String.class).invoke(attach, absp);204 vm.getMethod("detach").invoke(attach);205 return;206 }207 } catch (Throwable e) {208 allFails.add(e);209 }210 LinkageError error = new LinkageError("Failed to attach self, try upgrade your java version or use JDK");211 for (Throwable t : allFails) {212 error.addSuppressed(t);213 }214 throw error;215 }216 private static void fetchInst(String cname) throws Throwable {217 Class<?> c = Class.forName(cname, false, ClassLoader.getSystemClassLoader());...
Source:IConstants.java
...46 /** The method name for MonitoredHost#activeVms(). */47 static final String ACTIVE_VMS_METHOD = "activeVms";48 /** The qualified class name for VirtualMachine. */49 static final String VIRTUAL_MACHINE_CLASS = "com.sun.tools.attach.VirtualMachine";50 /** The method name for VirtualMachine#loadAgent(). */51 static final String LOAD_AGENT_METHOD = "loadAgent";52 /** The method name for VirtualMachine#detach(). */53 static final String DETACH_METHOD = "detach";54 /** The method name for VirtualMachine#getSystemProperties(). */55 static final String GET_SYSTEM_PROPERTIES_METHOD = "getSystemProperties";56 /** The method name for VirtualMachine#getMonitoredHost(). */57 static final String GET_MONITORED_HOST_CLASS = "getMonitoredHost";58 /** The method name for VirtualMachine#getAgentProperties(). */59 static final String GET_AGENT_PROPERTIES_METHOD = "getAgentProperties";60 /** The method name for URLClassLoader#addURL(). */61 static final String ADD_URL_METHOD = "addURL";62 /** The method name for VirtualMachine#attach(). */63 static final String ATTACH_METHOD = "attach";64 /** The library name for attach. */65 static final String ATTACH_LIBRARY = "attach";...
Source:MyAgent.java
...54 */55 public static void loadVirtualMachine() throws Exception{56 String jvmPid="targetPid";57// VirtualMachine jvm = VirtualMachine.attach(jvmPid);58// jvm.loadAgent(agentFilePath);//agentFilePath为agentçè·¯å¾59// jvm.detach();60// logger.info("Attached to target JVM and loaded Java agent successfully");61 //å®é
è¿åçæ¯ hotspotVirtualMachine å®ç°ç±»62 VirtualMachine virtualMachine = VirtualMachine.attach(jvmPid);63 virtualMachine.loadAgent("agentFilePath");64 virtualMachine.detach();65 }66}...
loadAgent
Using AI Code Generation
1import java.io.IOException;2import com.sun.tools.attach.VirtualMachine;3import com.sun.tools.attach.AttachNotSupportedException;4import com.sun.tools.attach.VirtualMachineDescriptor;5import java.util.List;6public class 4 {7public static void main(String[] args) {8String agentPath = "C:\\Users\\Administrator\\Desktop\\agent.jar";9List<VirtualMachineDescriptor> vmlist = VirtualMachine.list();10for (VirtualMachineDescriptor vmd : vmlist) {11System.out.println(vmd.id() + " " + vmd.displayName());12}13VirtualMachine vm = null;14try {15vm = VirtualMachine.attach("8044");16vm.loadAgent(agentPath);17vm.detach();18} catch (AttachNotSupportedException e) {19e.printStackTrace();20} catch (IOException e) {21e.printStackTrace();22}23}24}25import java.lang.instrument.Instrumentation;26public class agent {27public static void premain(String agentArgs, Instrumentation inst) {28inst.addTransformer(new agent());29}30public byte[] transform(ClassLoader loader, String className, Class<?> classBeingRedefined, java.security.ProtectionDomain protectionDomain, byte[] classfileBuffer) {31if(className.equals("java/lang/Thread")) {32System.out.println("Thread class is being loaded");33}34return null;35}36}
loadAgent
Using AI Code Generation
1import com.sun.tools.attach.VirtualMachine;2import com.sun.tools.attach.VirtualMachineDescriptor;3import java.io.IOException;4import java.util.List;5public class 4 {6 public static void main(String[] args) throws IOException {7 List<VirtualMachineDescriptor> vmlist = VirtualMachine.list();8 for (VirtualMachineDescriptor vmd : vmlist) {9 if (vmd.displayName().equals("4")) {10 VirtualMachine vm = VirtualMachine.attach(vmd);11 vm.loadAgent("C:\\Users\\user\\Desktop\\4\\4\\agent\\agent.jar");12 vm.detach();13 }14 }15 }16}17jvmtiEnv *jvmti;18jvmtiCapabilities caps;19jvmtiEventCallbacks callbacks;20void JNICALL VMInit(jvmtiEnv *jvmti_env, JNIEnv *env, jthread thread) {21 jclass cls = env->FindClass("java/lang/System");22 jfieldID fid = env->GetStaticFieldID(cls, "out", "Ljava/io/PrintStream;");23 jobject out = env->GetStaticObjectField(cls, fid);24 jclass ps_cls = env->FindClass("java/io/PrintStream");25 jmethodID mid = env->GetMethodID(ps_cls, "println", "(Ljava/lang/String;)V");26 jstring message = env->NewStringUTF("Hello World");27 env->CallVoidMethod(out, mid, message);28}29void JNICALL VMDeath(jvmtiEnv *jvmti_env) {30 printf("VM is shutting down");31}32void JNICALL ThreadStart(jvmtiEnv *jvmti_env, JNIEnv *env, jthread thread) {33 printf("thread started");34}35void JNICALL ThreadEnd(jvmtiEnv *jvmti_env, JNIEnv *env, jthread thread) {36 printf("thread ended");37}38void JNICALL ClassFileLoadHook(jvmtiEnv *jvmti_env, JNIEnv
loadAgent
Using AI Code Generation
1import sun.tools.attach.HotSpotVirtualMachine;2import java.io.File;3public class 4 {4 public static void main(String[] args) throws Exception {5 HotSpotVirtualMachine vm = HotSpotVirtualMachine.attach("12345");6 File agentFile = new File("agent.so");7 vm.loadAgent(agentFile.getAbsolutePath());8 }9}10JNIEXPORT jint JNICALL Agent_OnLoad(JavaVM *jvm, char *options, void *reserved) {11 jvmtiEnv *jvmti;12 jvmtiCapabilities capabilities;13 jvmtiError error;14 (*jvm)->GetEnv(jvm, (void **)&jvmti, JVMTI_VERSION_1_0);15 if (error != JVMTI_ERROR_NONE) {16 printf("Unable to get JVMTI environment17");18 exit(1);19 }20 capabilities.can_generate_field_modification_events = 1;21 capabilities.can_generate_field_access_events = 1;22 capabilities.can_generate_breakpoint_events = 1;23 capabilities.can_generate_single_step_events = 1;24 capabilities.can_generate_exception_events = 1;25 capabilities.can_generate_frame_pop_events = 1;26 capabilities.can_generate_method_entry_events = 1;27 capabilities.can_generate_method_exit_events = 1;28 capabilities.can_generate_native_method_bind_events = 1;29 capabilities.can_generate_compiled_method_load_events = 1;30 capabilities.can_generate_monitor_events = 1;31 capabilities.can_generate_vm_object_alloc_events = 1;32 capabilities.can_generate_native_method_bind_events = 1;33 capabilities.can_generate_garbage_collection_events = 1;34 capabilities.can_generate_object_free_events = 1;35 capabilities.can_tag_objects = 1;36 capabilities.can_generate_all_class_hook_events = 1;37 capabilities.can_generate_compiled_method_load_events = 1;38 capabilities.can_generate_monitor_events = 1;39 capabilities.can_generate_vm_object_alloc_events = 1;40 capabilities.can_retransform_classes = 1;41 capabilities.can_retransform_any_class = 1;42 capabilities.can_get_owned_monitor_info = 1;43 capabilities.can_get_current_contended_monitor = 1;
loadAgent
Using AI Code Generation
1import java.io.*;2import java.lang.management.*;3import java.lang.reflect.*;4import java.util.*;5import sun.tools.attach.*;6public class 4 {7 public static void main(String[] args) throws Exception {8 if (args.length != 2) {9 System.out.println("Usage: java 4 <pid> <agent class name>");10 System.exit(1);11 }12 String pid = args[0];13 String agentClassName = args[1];14 System.out.println("pid = " + pid + ", agent class name = " + agentClassName);15 HotSpotVirtualMachine vm = (HotSpotVirtualMachine)VirtualMachine.attach(pid);16 vm.loadAgent(agentClassName + ".jar");17 vm.detach();18 }19}20import java.lang.management.*;21import java.lang.reflect.*;22import java.util.*;23public class agent {24 public static void agentmain(String agentArgs, Instrumentation inst) throws Exception {25 System.out.println("agentmain method invoked...");26 System.out.println("agentArgs = " + agentArgs);27 System.out.println("inst = " + inst);28 System.out.println("Class path:");29 String classPath = System.getProperty("java.class.path");30 String[] classPathElements = classPath.split(":");31 for (String classPathElement : classPathElements) {32 System.out.println(classPathElement);33 }34 }35}
loadAgent
Using AI Code Generation
1import sun.tools.attach.*;2import java.io.IOException;3public class 4 {4 public static void main(String[] args) throws IOException {5 String pid = args[0];6 String agentPath = args[1];7 HotSpotVirtualMachine vm = (HotSpotVirtualMachine) VirtualMachine.attach(pid);8 vm.loadAgent(agentPath);9 vm.detach();10 }11}12import java.lang.instrument.Instrumentation;13public class Agent {14 public static void premain(String agentArgs, Instrumentation inst) {15 System.out.println("Hello World");16 }17}18import sun.tools.attach.*;19import java.io.IOException;20public class 4 {21 public static void main(String[] args) throws IOException {22 String pid = args[0];23 String agentPath = args[1];24 HotSpotVirtualMachine vm = (HotSpotVirtualMachine) VirtualMachine.attach(pid);25 vm.loadAgent(agentPath);26 vm.detach();27 }28}29import java.lang.instrument.Instrumentation;30public class Agent {31 public static void premain(String agentArgs, Instrumentation inst) {
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