Java VM类代码示例

import sun.jvm.hotspot.runtime.VM; //导入依赖的package包/类
public void doit(Tokens t) {
    if (t.countTokens() != 0) {
        usage();
    } else {
        Universe u = VM.getVM().getUniverse();
        out.println("Heap Parameters:");
        u.heap().printOn(out);
    }
}
 

import sun.jvm.hotspot.runtime.VM; //导入依赖的package包/类
/** this functions used for core file reading and called from native attach0,
    it returns an array of long integers as
    [thread_id, stack_start, stack_end, thread_id, stack_start, stack_end, ....] for
    all java threads recorded in Threads. Also adds the ThreadProxy to threadList */
public long[] getJavaThreadsInfo() {
    requireAttach();
    Threads threads = VM.getVM().getThreads();
    int len = threads.getNumberOfThreads();
    long[] result = new long[len * 3];    // triple
    JavaThread t = threads.first();
    long beg, end;
    int i = 0;
    while (t != null) {
        end = t.getStackBaseValue();
        beg = end - t.getStackSize();
        BsdThread bsdt = (BsdThread)t.getThreadProxy();
        long uid = bsdt.getUniqueThreadId();
        if (threadList != null) threadList.add(bsdt);
        result[i] = uid;
        result[i + 1] = beg;
        result[i + 2] = end;
        t = t.next();
        i += 3;
    }
    return result;
}
 

import sun.jvm.hotspot.runtime.VM; //导入依赖的package包/类
Address lookup(String symbol) {
    if (symbol.indexOf("::") != -1) {
        String[] parts = symbol.split("::");
        StringBuffer mangled = new StringBuffer("__1c");
        for (int i = 0; i < parts.length; i++) {
            int len = parts[i].length();
            if (len >= 26) {
                mangled.append((char)('a' + (len / 26)));
                len = len % 26;
            }
            mangled.append((char)('A' + len));
            mangled.append(parts[i]);
        }
        mangled.append("_");
        symbol = mangled.toString();
    }
    return VM.getVM().getDebugger().lookup(null, symbol);
}
 

import sun.jvm.hotspot.runtime.VM; //导入依赖的package包/类
public void doit(Tokens t) {
    int tokens = t.countTokens();
    if (tokens != 1) {
        usage();
        return;
    }
    String name = t.nextToken();
    Address addr = null;
    try {
        addr = VM.getVM().getDebugger().parseAddress(name);
    } catch (NumberFormatException e) {
       out.println(e);
       return;
    }

    HTMLGenerator generator = new HTMLGenerator(false);
    out.println(generator.genHTML(addr));
}
 

import sun.jvm.hotspot.runtime.VM; //导入依赖的package包/类
private static void initialize(TypeDataBase db) {
  Type type = db.lookupType("CodeBlob");

  nameField                = type.getAddressField("_name");
  sizeField                = type.getCIntegerField("_size");
  headerSizeField          = type.getCIntegerField("_header_size");
  frameCompleteOffsetField = type.getCIntegerField("_frame_complete_offset");
  contentBeginField        = type.getAddressField("_content_begin");
  codeBeginField           = type.getAddressField("_code_begin");
  codeEndField             = type.getAddressField("_code_end");
  dataEndField             = type.getAddressField("_data_end");
  dataOffsetField          = type.getCIntegerField("_data_offset");
  frameSizeField           = type.getCIntegerField("_frame_size");
  oopMapsField             = type.getAddressField("_oop_maps");

  if (VM.getVM().isServerCompiler()) {
    matcherInterpreterFramePointerReg =
        db.lookupIntConstant("Matcher::interpreter_frame_pointer_reg").intValue();
  }
}
 

import sun.jvm.hotspot.runtime.VM; //导入依赖的package包/类
private void startInternal() {

      PrintStream out = System.out;
      VM vm = VM.getVM();
      if (vm.isCore()) {
        out.println("Core build detected.");
      } else if (vm.isClientCompiler()) {
        out.println("Client compiler detected.");
      } else if (vm.isServerCompiler()) {
        out.println("Server compiler detected.");
      } else {
        throw new RuntimeException("Fatal error: "
            + "should have been able to detect core/C1/C2 build");
      }

      String version = vm.getVMRelease();
      if (version != null) {
        out.print("JVM version is ");
        out.println(version);
      }

      run();
   }
 

import sun.jvm.hotspot.runtime.VM; //导入依赖的package包/类
@Override
public void run() {
    SystemDictionary dictionary = VM.getVM().getSystemDictionary();
    Klass klass = dictionary.find("java/security/PrivateKey", null, null);

    VM.getVM().getObjectHeap().iterateObjectsOfKlass(new DefaultHeapVisitor() {
        @Override
        public boolean doObj(Oop oop) {
            oop.iterate(new KeyPrinter(), false);
            return false;
        }
    }, klass);
}
 

import sun.jvm.hotspot.runtime.VM; //导入依赖的package包/类
private boolean detachInternal() {
    if (debugger == null) {
        return false;
    }
    boolean retval = true;
    if (!isServer) {
        VM.shutdown();
    }
    // We must not call detach() if we are a client and are connected
    // to a remote debugger
    Debugger dbg = null;
    DebuggerException ex = null;
    if (isServer) {
        try {
            RMIHelper.unbind(serverID);
        }
        catch (DebuggerException de) {
            ex = de;
        }
        dbg = debugger;
    } else {
        if (startupMode != REMOTE_MODE) {
            dbg = debugger;
        }
    }
    if (dbg != null) {
        retval = dbg.detach();
    }

    debugger = null;
    machDesc = null;
    db = null;
    if (ex != null) {
        throw(ex);
    }
    return retval;
}
 

import sun.jvm.hotspot.runtime.VM; //导入依赖的package包/类
private HeapRegion at(long index) {
    Address arrayAddr = regionsField.getValue(addr);
    // Offset of &_region[index]
    long offset = index * VM.getVM().getAddressSize();
    Address regionAddr = arrayAddr.getAddressAt(offset);
    return (HeapRegion) VMObjectFactory.newObject(HeapRegion.class,
                                                  regionAddr);
}
 

import sun.jvm.hotspot.runtime.VM; //导入依赖的package包/类
public static void decode(InstructionVisitor visitor, CodeBlob blob, Address begin, Address end) {
   int codeSize = (int)end.minus(begin);
   long startPc = VM.getAddressValue(begin);
   byte[] code = new byte[codeSize];
   for (int i = 0; i < code.length; i++)
      code[i] = begin.getJByteAt(i);
   Disassembler dis = new Disassembler(startPc, code);
   dis.decode(visitor);
}
 

import sun.jvm.hotspot.runtime.VM; //导入依赖的package包/类
private void init() {
    saVM = VM.getVM();
    saUniverse = saVM.getUniverse();
    saSystemDictionary = saVM.getSystemDictionary();
    saSymbolTable = saVM.getSymbolTable();
    saObjectHeap = saVM.getObjectHeap();
    initClassNameSymbols();
}
 

import sun.jvm.hotspot.runtime.VM; //导入依赖的package包/类
private HeapRegion at(long index) {
    Address arrayAddr = baseField.getValue(addr);
    // Offset of &_base[index]
    long offset = index * VM.getVM().getAddressSize();
    Address regionAddr = arrayAddr.getAddressAt(offset);
    return (HeapRegion) VMObjectFactory.newObject(HeapRegion.class,
                                                  regionAddr);
}