I am integrating with an aged lm_sensors library using JNA and JNAerator, with a view to creating MBeans for each of the temperature sensors inside my box. Firstly I'm calling this method:
// C edition
const sensors_chip_name *sensors_get_detected_chips(int *nr);
// Java edition
sensors_chip_name sensors_get_detected_chips(IntByReference nr);
.. which works just fine. Subsequently I need to call:
// C edition
int sensors_get_feature(sensors_chip_name name, int feature, double *result);
// Java edition
int sensors_get_feature(sensors_chip_name.ByValue name, int feature, DoubleByReference result);
.. what I am lacking is how to take the result of sensors_get_detected_chips and pass it by value to the 1st argument of sensors_get_feature.
The following allows a ByValue version of the struct to be initialized from the base class.
public class sensors_chip_name extends Structure {
public class ByValue extends sensors_chip_name implements Structure.ByValue {
public ByValue(sensors_chip_name orig) {
this(orig.getPointer().share());
}
public ByValue(Pointer p) {
super(p);
}
public ByValue() { }
}
public sensors_chip_name() { }
public sensors_chip_name(Pointer p) {
super(p);
read();
}
}
Related
I'm trying to create a Map from a List using Streams.
The key should be the name of the original item,
The value should be some derived data.
After .map() the stream consists of Integers and at the time of .collect() I can't access "foo" from the previous lambda. How do I get the original item in .toMap()?
Can this be done with Streams or do I need .forEach()?
(The code below is only for demonstration, the real code is of course much more complex and I can't make doSomething() a method of Foo).
import java.util.ArrayList;
import java.util.Map;
import java.util.function.Function;
import java.util.stream.Collectors;
public class StreamTest {
public class Foo {
public String getName() {
return "FOO";
}
public Integer getValue() {
return 42;
}
}
public Integer doSomething(Foo foo) {
return foo.getValue() + 23;
}
public Map<String, Integer> run() {
return new ArrayList<Foo>().stream().map(foo -> doSomething(foo)).collect(Collectors.toMap(foo.getName, Function.identity()));
}
public static void main(String[] args) {
StreamTest streamTest = new StreamTest();
streamTest.run();
}
}
It appears to me it’s not that complicated. Am I missing something?
return Stream.of(new Foo())
.collect(Collectors.toMap(Foo::getName, this::doSomething));
I’m rather much into method references. If you prefer the -> notation, use
return Stream.of(new Foo())
.collect(Collectors.toMap(foo -> foo.getName(), foo -> doSomething(foo)));
Either will break (throw an exception) if there’s more than one Foo with the same name in your stream.
I have a combo box over my GUI in JavaFX.
This Combo Box is composed of a complex type elements :
public class DureeChoiceBoxElement extends ObservableValueBase<DureeChoiceBoxElement> {
private IntegerProperty duree;
#Override
public String toString() {
return duree.get() + " an";
}
}
I want to map (or bind) the selected complex element with my model which contains the simple type :
public class Pel {
private IntegerProperty duree = new SimpleIntegerProperty(1);
public Property<Number> dureeProperty() {
return duree;
}
public void setDuree(Integer duree) {
this.duree.setValue(duree);
}
public Integer getDuree() {
return duree.getValue();
}
}
How to do it ?
I tried in the controller with :
public class PelController {
#FXML
private ChoiceBox<DureeChoiceBoxElement> duree;
//etc..
pel.dureeProperty().bind(createElapsedBindingByBindingsAPI2(duree.getValue()));
/*
* #return an ObjectBinding of immutable TimeElapsed objects for the player
*/
private ObjectBinding<Property<Number>> createElapsedBindingByBindingsAPI2(
final DureeChoiceBoxElement dureeChoiceBoxElement) {
return Bindings.createObjectBinding(new Callable<Property<Number>>() {
#Override
public IntegerProperty call() throws Exception {
return dureeChoiceBoxElement.dureeProperty();
}
}, dureeChoiceBoxElement.dureeProperty());
}
}
But it doesn't work (even not compile). I want to say that "Bind this simple property to this complex Object calling the method I give you through the method named "createElapsedBindingByBindingsAPI2(..)".
It is logical read but I didn't managed to make it works anyway.
That's poor ....
Any help please :).
Example that (obviously) works with legacy code style (Swing coding) :
duree.getSelectionModel().selectedItemProperty().addListener(new ChangeListener<DureeChoiceBoxElement>() {
#Override
public void changed(ObservableValue<? extends DureeChoiceBoxElement> observable,
DureeChoiceBoxElement oldValue, DureeChoiceBoxElement newValue) {
// changement durée
log.debug("Durée sélectionnée : {}", duree.getSelectionModel().getSelectedItem().getDuree());
log.debug("Durée bindée ? : {}", pel.getDuree());
pel.setDuree(duree.getSelectionModel().getSelectedItem().getDuree());
}
});
Like this my model is set to selected item. But it implies some boilerplate code. Any better idea based on high level bindings of JavaFX ?
I am new to JMX and now I wished to monitor my project with JMX. Is there any way to return user defined class via MBeans/MXBean? I know that OpentType can help but don't know how to used it. I also went through Composite and Tabular data types but it may not work for me because I need to convert each and every class into respective data types.
Please provide your help.
Thank you in advance!!
You have to create an Interface SomethingMBean and a class that implement that interface.
public interface HelloMBean {
public void sayHello();
public int add(int x, int y);
public String getName();
public int getCacheSize();
public void setCacheSize(int size);
}
public class Hello ...
implements HelloMBean {
public void sayHello() {
System.out.println("hello, world");
}
public int add(int x, int y) {
return x + y;
}
public String getName() {
return this.name;
}
public int getCacheSize() {
return this.cacheSize;
}
public synchronized void setCacheSize(int size) {
...
this.cacheSize = size;
System.out.println("Cache size now " + this.cacheSize);
}
...
private final String name = "Reginald";
private int cacheSize = DEFAULT_CACHE_SIZE;
private static final int
DEFAULT_CACHE_SIZE = 200;
}
And then, you have to register your MBean...
MBeanServer mbs = ManagementFactory.getPlatformMBeanServer();
ObjectName name = new ObjectName("com.example:type=Hello");
Hello mbean = new Hello();
mbs.registerMBean(mbean, name);
Take a look at Java Tutorial
If your project is using Spring, then it is quite easy to expose any user-defined class to JMX by simply using annotations:
#ManagedResource - to expose the class to JMX
#ManagedAttribute - to expose any fields of a ManagedResource class as attributes
#ManagedOperation - to expose any method of a ManagedResource class
as an operation
Have a look at the official Spring documentation which contains quite a few illustrative examples as well.
So basically, I have a situation where I want to inject primitive types into a class (i.e. a String and an Integer). You can think of a URL and port number for an application as example inputs. I have three components:
Now say I have a class, which does take in these params:
public class PrimitiveParamsDIExample {
private String a;
private Integer b;
public PrimitiveParamsDIExample(String a, Integer b) {
this.a = a;
this.b = b;
}
}
So my question here is simple. How do I inject a and b into class PrimitiveParamsDIExample?
In general, this is also asking how to inject parameters that are decided on runtime as well. If I have a and b above, read from STDIN or from an input file, they're obviously going to be different from run to run.
All the more, how do I do the above within the HK2 framework?
EDIT[02/23/15]: #jwells131313, I tried your idea, but I'm getting the following error (this one for the String param; similar one for int):
org.glassfish.hk2.api.UnsatisfiedDependencyException: There was no object available for injection at Injectee(requiredType=String,parent=PrimitiveParamsDIExample,qualifiers
I set up classes exactly as you did in your answer. I also overrode the toString() method to print both variables a and b in PrimitiveParamsDIExample. Then, I added the following in my Hk2Module class:
public class Hk2Module extends AbstractBinder {
private Properties properties;
public Hk2Module(Properties properties){
this.properties = properties;
}
#Override
protected void configure() {
bindFactory(StringAFactory.class).to(String.class).in(RequestScoped.class);
bindFactory(IntegerBFactory.class).to(Integer.class).in(RequestScoped.class);
bind(PrimitiveParamsDIExample.class).to(PrimitiveParamsDIExample.class).in(Singleton.class);
}
}
So now, I created a test class as follows:
#RunWith(JUnit4.class)
public class TestPrimitiveParamsDIExample extends Hk2Setup {
private PrimitiveParamsDIExample example;
#Before
public void setup() throws IOException {
super.setupHk2();
//example = new PrimitiveParamsDIExample();
example = serviceLocator.getService(PrimitiveParamsDIExample.class);
}
#Test
public void testPrimitiveParamsDI() {
System.out.println(example.toString());
}
}
where, Hk2Setup is as follows:
public class Hk2Setup extends TestCase{
// the name of the resource containing the default configuration properties
private static final String DEFAULT_PROPERTIES = "defaults.properties";
protected Properties config = null;
protected ServiceLocator serviceLocator;
public void setupHk2() throws IOException{
config = new Properties();
Reader defaults = Resources.asCharSource(Resources.getResource(DEFAULT_PROPERTIES), Charsets.UTF_8).openBufferedStream();
load(config, defaults);
ApplicationHandler handler = new ApplicationHandler(new MyMainApplication(config));
final ServiceLocator locator = handler.getServiceLocator();
serviceLocator = locator;
}
private static void load(Properties p, Reader r) throws IOException {
try {
p.load(r);
} finally {
Closeables.close(r, false);
}
}
}
So somewhere, the wiring is messed up for me to get an UnsatisfiedDependencyException. What have I not correctly wired up?
Thanks!
There are two ways to do this, but one isn't documented yet (though it is available... I guess I need to work on documentation again...)
I'll go through the first way here.
Basically, you can use the HK2 Factory.
Generally when you start producing Strings and ints and long and scalars like this you qualify them, so lets start with two qualifiers:
#Retention(RUNTIME)
#Target( { TYPE, METHOD, FIELD, PARAMETER })
#javax.inject.Qualifier
public #interface A {}
and
#Retention(RUNTIME)
#Target( { TYPE, METHOD, FIELD, PARAMETER })
#javax.inject.Qualifier
public #interface B {}
then write your factories:
#Singleton // or whatever scope you want
public class StringAFactory implements Factory<String> {
#PerLookup // or whatever scope, maybe this checks the timestamp?
#A // Your qualifier
public String provide() {
// Write your code to get your value...
return whatever;
}
public void dispose(String instance) {
// Probably do nothing...
}
}
and for the Integer:
#Singleton // or whatever scope you want
public class IntegerBFactory implements Factory<Integer> {
#PerLookup // or whatever scope, maybe this checks the timestamp?
#B // Your qualifier
public Integer provide() {
// Write your code to get your value...
return whatever;
}
public void dispose(String instance) {
// Probably do nothing...
}
}
Now lets re-do your original class to accept these values:
public class PrimitiveParamsDIExample {
private String a;
private int b;
#Inject
public PrimitiveParamsDIExample(#A String a, #B int b) {
this.a = a;
this.b = b;
}
}
Note I changed Integer to int, well... just because I can. You can also just use field injection or method injection in the same way. Here is field injection, method injection is an exercise for the reader:
public class PrimitiveParamsDIExample {
#Inject #A
private String a;
#Inject #B
private int b;
public PrimitiveParamsDIExample() {
}
}
There are several ways to bind factories.
In a binder: bindFactory
Using automatic class analysis: addClasses
An EDSL outside a binder: buildFactory
I am implementing an interface for taking commands for creating , connecting and coloring vertices in JUNG when I want to connect two already existing vertices JUNG connects to vertices and creates an extra vertex , why?
Here is my code for connect method:
public class Connect extends Command {
private CommandMaster cm;
private BehGraphUndirected behGraph;
private static int edgenumber=0;
#Override
public Object run(BehGraphUndirected behGraph, VisualizationImageServer panel, InterpretMaster interpretMaster, String... args) {
System.out.print("connect Runs\n");
this.cm = new CommandMaster();
this.behGraph = behGraph;
if(cm.exists(args[0]))
{
//got to another command
}else
{
switch (args[0]) {
case "edge":
this.createEdge(args[1] , args[2]);
break;
}
}
interpretMaster.refreshAndRepaint();
return null;
}
public void createEdge(String nodeName1 , String nodeName2)
{
this.behGraph.addEdge(edgenumber++,nodeName1, nodeName2);
System.out.println(this.behGraph.getVertexCount());
System.out.println("edge between: "+nodeName1+" and "+ nodeName2+" added");
}
And it's the create method just in case you want to know the way I implemented the code:
package interpreter.command;
import GraphHandling.BehGraphUndirected;
import edu.uci.ics.jung.visualization.VisualizationImageServer;
import interpreter.Command;
import interpreter.CommandMaster;
import interpreter.InterpretMaster;
/**
*
* #author Administrator
*/
public class Create extends Command{
private CommandMaster cm;
private BehGraphUndirected behGraph;
#Override
public Object run(BehGraphUndirected behGraph, VisualizationImageServer panel, InterpretMaster interpretMaster, String... args) {
System.out.print("create Runs \n");
this.cm = new CommandMaster();
this.behGraph = behGraph;
if(cm.exists(args[0]))
{
//got to another command
}else
{
switch (args[0]) {
case "node":
this.createNode(args[1]);
break;
case "label":
this.createLabel(args[1]);
break;
}
}
interpretMaster.refreshAndRepaint();
return null;
}
public void createNode(String nodeName)
{
this.behGraph.addVertex(nodeName);
System.out.print("vertex: "+nodeName+" added");
}
private void createLabel(String string) {
}
class str
{
int i;
long j;
}
}
Graph images before and after connecting two nodes:
and Here is my BehGraphUndirected class:
package GraphHandling;
import edu.uci.ics.jung.graph.UndirectedSparseGraph;
import java.util.LinkedList;
/**
*
* #author Administrator
*/
public class BehGraphUndirected extends UndirectedSparseGraph{
private final LinkedList<Node> nodeList;
public BehGraphUndirected()
{
this.nodeList = new LinkedList<>();
}
public void addNode(Node newNode)
{
this.nodeList.add(newNode);
}
}
You should look at what BehGraphUndirected is doing; it's not a JUNG class or interface.
What is the name of the vertex that's being created, and how does that relate to what's being passed to the create method?
I have compiled and tested your code , The Jung library seems working right and It extinguishes the different nodes by the different object that was given to it It seems you have some other problem , Like a problem in processing the input strings that are used as objects that create nodes.