/**
* Create a PerfDataBuffer instance for accessing the specified instrumentation buffer.
*
* @param vmid the <em>file:</em> URI to the instrumentation buffer file
* @throws MonitorException
*/
public PerfDataBuffer(VmIdentifier vmid) throws MonitorException {
File f = new File(vmid.getURI());
String mode = vmid.getMode();
try {
FileChannel fc = new RandomAccessFile(f, mode).getChannel();
ByteBuffer bb = null;
if (mode.compareTo("r") == 0) {
bb = fc.map(FileChannel.MapMode.READ_ONLY, 0L, (int) fc.size());
} else if (mode.compareTo("rw") == 0) {
bb = fc.map(FileChannel.MapMode.READ_WRITE, 0L, (int) fc.size());
} else {
throw new IllegalArgumentException("Invalid mode: " + mode);
}
fc.close(); // doesn't need to remain open
createPerfDataBuffer(bb, 0);
} catch (FileNotFoundException e) {
throw new MonitorException("Could not find " + vmid.toString());
} catch (IOException e) {
throw new MonitorException("Could not read " + vmid.toString());
}
}
/** {@inheritDoc} */
public MonitoredVm getMonitoredVm(VmIdentifier vmid, int interval) throws MonitorException {
VmIdentifier nvmid = null;
try {
nvmid = hostId.resolve(vmid);
RemoteVm rvm = remoteHost.attachVm(vmid.getLocalVmId(), vmid.getMode());
RemoteMonitoredVm rmvm = new RemoteMonitoredVm(rvm, nvmid, timer, interval);
rmvm.attach();
return rmvm;
} catch (RemoteException e) {
throw new MonitorException("Remote Exception attaching to " + nvmid.toString(), e);
} catch (URISyntaxException e) {
/*
* the VmIdentifier is expected to be a valid and should resolve
* easonably against the host identifier. A URISyntaxException
* here is most likely a programming error.
*/
throw new IllegalArgumentException("Malformed URI: " + vmid.toString(), e);
}
}
/**
* Resolve a VmIdentifier with this HostIdentifier. A VmIdentifier, such as <em>1234</em> or
* <em>1234@hostname</em> or any other string that omits certain components of the URI string may
* be valid, but is certainly incomplete. They are missing critical information for identifying
* the the communications protocol, target host, or other parameters. A VmIdentifier of this form
* is considered <em>unresolved</em>. This method uses components of the HostIdentifier to resolve
* the missing components of the VmIdentifier.
*
* <p>Specified components of the unresolved VmIdentifier take precedence over their
* HostIdentifier counterparts. For example, if the VmIdentifier indicates
* <em>1234@hostname:2099</em> and the HostIdentifier indicates <em>rmi://hostname:1099/</em>,
* then the resolved VmIdentifier will be <em>rmi://1234@hostname:2099</em>. Any component not
* explicitly specified or assumed by the HostIdentifier, will remain unresolved in resolved
* VmIdentifier.
*
* <p>A VmIdentifier specifying a <em>file:</em> scheme (protocol), is not changed in any way by
* this method.
*
* @param vmid the unresolved VmIdentifier.
* @return VmIdentifier - the resolved VmIdentifier. If vmid was resolved on entry to this method,
* then the returned VmIdentifier will be equal, but not identical, to vmid.
*/
public VmIdentifier resolve(VmIdentifier vmid) throws URISyntaxException, MonitorException {
String scheme = vmid.getScheme();
String host = vmid.getHost();
String authority = vmid.getAuthority();
if ((scheme != null) && (scheme.compareTo("file") == 0)) {
// don't attempt to resolve a file based VmIdentifier.
return vmid;
}
if ((host != null) && (host.compareTo(authority) == 0)) {
/*
* this condition occurs when the VmIdentifier specifies only the authority (i.e. an lvmid), and not a host name.
*/
host = null;
}
if (scheme == null) {
scheme = getScheme();
}
StringBuffer sb = new StringBuffer();
sb.append(scheme).append("://");
String userInfo = vmid.getUserInfo();
if (userInfo != null) {
sb.append(userInfo);
} else {
sb.append(vmid.getAuthority());
}
if (host == null) {
host = getHost();
}
sb.append("@").append(host);
int port = vmid.getPort();
if (port == -1) {
port = getPort();
}
if (port != -1) {
sb.append(":").append(port);
}
String path = vmid.getPath();
if ((path == null) || (path.length() == 0)) {
path = getPath();
}
if ((path != null) && (path.length() > 0)) {
sb.append(path);
}
String query = vmid.getQuery();
if (query == null) {
query = getQuery();
}
if (query != null) {
sb.append("?").append(query);
}
String fragment = vmid.getFragment();
if (fragment == null) {
fragment = getFragment();
}
if (fragment != null) {
sb.append("#").append(fragment);
}
String s = sb.toString();
return new VmIdentifier(s);
}
/**
* Create a HostIdentifier instance from a VmIdentifier.
*
* <p>The necessary components of the VmIdentifier are extracted and reassembled into a
* HostIdentifier. If a "file:" scheme (protocol) is specified, the the returned HostIdentifier
* will always be equivalent to HostIdentifier("file://localhost").
*
* @param vmid the VmIdentifier use to construct the HostIdentifier.
*/
public HostIdentifier(VmIdentifier vmid) {
/*
* Extract all components of the VmIdentifier URI except the user-info part of the authority (the lvmid).
*/
StringBuilder sb = new StringBuilder();
String scheme = vmid.getScheme();
String host = vmid.getHost();
String authority = vmid.getAuthority();
// check for 'file:' VmIdentifiers and handled as a special case.
if ((scheme != null) && (scheme.compareTo("file") == 0)) {
try {
uri = new URI("file://localhost");
} catch (URISyntaxException e) {
}
;
return;
}
if ((host != null) && (host.compareTo(authority) == 0)) {
/*
* this condition occurs when the VmIdentifier specifies only the authority (i.e. the lvmid ), and not a host name.
*/
host = null;
}
if (scheme == null) {
if (host == null) {
scheme = "local"; // default local scheme
} else {
/*
* rmi is the default remote scheme. if the VmIdentifier specifies some other protocol, this default is overridden.
*/
scheme = "rmi";
}
}
sb.append(scheme).append("://");
if (host == null) {
sb.append("localhost"); // default host name
} else {
sb.append(host);
}
int port = vmid.getPort();
if (port != -1) {
sb.append(":").append(port);
}
String path = vmid.getPath();
if ((path != null) && (path.length() != 0)) {
sb.append(path);
}
String query = vmid.getQuery();
if (query != null) {
sb.append("?").append(query);
}
String frag = vmid.getFragment();
if (frag != null) {
sb.append("#").append(frag);
}
try {
uri = new URI(sb.toString());
} catch (URISyntaxException e) {
// shouldn't happen, as we were passed a valid VmIdentifier
throw new RuntimeException("Internal Error", e);
}
}
