Example usage for java.lang Class getConstructor

List of usage examples for java.lang Class getConstructor

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Introduction

In this page you can find the example usage for java.lang Class getConstructor.

Prototype

@CallerSensitive
public Constructor<T> getConstructor(Class<?>... parameterTypes)
        throws NoSuchMethodException, SecurityException

Source Link

Document

Returns a Constructor object that reflects the specified public constructor of the class represented by this Class object.

Usage

From source file:it.cnr.icar.eric.common.spi.LifeCycleManagerFactory.java

/**
* Creates the instance of the pluginClass
*//*  w  ww.  j a v  a  2s  . com*/
private Object createPluginInstance(String pluginClass) throws Exception {
    Object plugin = null;

    if (log.isDebugEnabled()) {
        log.debug("pluginClass = " + pluginClass);
    }

    Class<?> theClass = Class.forName(pluginClass);

    //try to invoke constructor using Reflection, 
    //if this fails then try invoking getInstance()
    try {
        Constructor<?> constructor = theClass.getConstructor((java.lang.Class[]) null);
        plugin = constructor.newInstance(new Object[0]);
    } catch (Exception e) {
        //log.warn("No accessible constructor. " +
        //    "invoking getInstance() instead.");

        Method factory = theClass.getDeclaredMethod("getInstance", (java.lang.Class[]) null);
        plugin = factory.invoke((java.lang.Class[]) null, new Object[0]);
    }

    return plugin;
}

From source file:it.cnr.icar.eric.common.spi.QueryManagerFactory.java

/**
* Creates the instance of the pluginClass
*//*from ww w  . ja  v  a2 s .  c om*/
private Object createPluginInstance(String pluginClass) throws Exception {
    Object plugin = null;

    if (log.isDebugEnabled()) {
        log.debug("pluginClass = " + pluginClass);
    }

    Class<?> theClass = Class.forName(pluginClass);

    //try to invoke constructor using Reflection, 
    //if this fails then try invoking getInstance()
    try {
        Constructor<?> constructor = theClass.getConstructor((java.lang.Class[]) null);
        plugin = constructor.newInstance(new Object[0]);
    } catch (Exception e) {
        //log.warn("No accessible constructor. " +
        //    "invoking getInstance() instead.");

        Method factory = theClass.getDeclaredMethod("getInstance", (java.lang.Class[]) null);
        plugin = factory.invoke(null, new Object[0]);
    }

    return plugin;
}

From source file:it.cnr.icar.eric.server.event.EventManagerFactory.java

/**
* Creates the instance of the pluginClass
*/// ww w .  ja v  a  2 s.  c om
private Object createPluginInstance(String pluginClass) throws Exception {
    Object plugin = null;

    if (log.isDebugEnabled()) {
        log.debug("pluginClass = " + pluginClass);
    }

    Class<?> theClass = Class.forName(pluginClass);

    //try to invoke constructor using Reflection, 
    //if this fails then try invoking getInstance()
    try {
        Constructor<?> constructor = theClass.getConstructor((java.lang.Class[]) null);
        plugin = constructor.newInstance(new Object[0]);
    } catch (Exception e) {
        //log.warn(ServerResourceBundle.getInstance().getString("message.NoAccessibleConstructorInvokingGetInstanceInstead"));

        Method factory = theClass.getDeclaredMethod("getInstance", (java.lang.Class[]) null);
        plugin = factory.invoke(null, new Object[0]);
    }

    return plugin;
}

From source file:org.openwms.core.aop.FireAfterTransactionAspect.java

/**
 * Only {@link ApplicationEvent}s are created and published over Springs
 * {@link ApplicationContext}./* ww w.  j av a  2s  .  co  m*/
 * 
 * @param publisher
 *            The instance that is publishing the event
 * @param events
 *            Stores a list of event classes to fire
 * @throws Exception
 *             Any exception is re-thrown
 */
@Async
public void fireEventAsync(Object publisher, FireAfterTransactionAsynchronous events) throws Exception {
    for (int i = 0; i < events.events().length; i++) {
        Class<? extends EventObject> event = events.events()[i];
        if (RootApplicationEvent.class.isAssignableFrom(event)) {
            LOGGER.debug("Sending event:" + event);
            ctx.publishEvent((RootApplicationEvent) event.getConstructor(Object.class).newInstance(publisher));
        }
    }
}

From source file:com.openmeap.web.form.ParameterMapBuilder.java

public void fromParameters(Object obj, Map<String, Object> parameters, String prefix)
        throws ParameterMapBuilderException {

    Class clazz = obj.getClass();
    for (Map.Entry<String, Object> entry : parameters.entrySet()) {

        String formName = entry.getKey().replaceFirst(prefix, "");
        if (entry.getValue() == null || (String.class.isAssignableFrom(entry.getValue().getClass())
                && StringUtils.isBlank((String) entry.getValue()))) {
            continue;
        }/*w  w  w  .  ja  v a2 s.c o m*/

        Method getterMethod = methodForFormName(clazz, formName);
        if (getterMethod == null) {
            continue;
        }
        Method setterMethod = PropertyUtils.setterForGetterMethod(getterMethod);
        Constructor constructor = null;

        Class<?> valueClass = null;
        try {
            valueClass = getterMethod.getReturnType();
            constructor = valueClass.getConstructor(valueClass);
        } catch (Exception e) {
            ;//throw new ParameterMapBuilderException(e);
        }

        Object value = null;
        try {
            if (this.useParameterMapUtilsFirstValue) {
                value = ParameterMapUtils.firstValue(formName, (Map) parameters);
            } else {
                value = parameters.get(formName);
            }
            if (value != null) {
                if (constructor != null) {
                    value = constructor.newInstance(value);
                } else {
                    value = PropertyUtils.correctCasting(valueClass, value);
                }
            }
        } catch (Exception e) {
            throw new ParameterMapBuilderException(e);
        }

        try {
            setterMethod.invoke(obj, value);
        } catch (Exception e) {
            throw new ParameterMapBuilderException(e);
        }
    }
}

From source file:net.dmulloy2.ultimatearena.api.SimpleArenaType.java

@Override
public ArenaConfig newConfig(ArenaZone az) {
    Class<? extends ArenaConfig> clazz = getArenaConfig();
    Validate.notNull(clazz, "ArenaConfig class cannot be null!");

    try {//from   w  w  w  .ja  v a 2  s . c  o m
        Constructor<? extends ArenaConfig> constructor = clazz.getConstructor(ArenaZone.class);
        return constructor.newInstance(az);
    } catch (InvocationTargetException ex) {
        throw new RuntimeException("Failed to create new " + clazz.getName() + " instance.", ex);
    } catch (Throwable ex) {
        throw Throwables.propagate(ex);
    }
}

From source file:com.adito.agent.client.ProxyUtil.java

/**
 * Attempt to proxy settings from Internet Explorer.
 * /*w  w  w  .j ava 2  s  . com*/
 * @return internet explorer proxy settings
 * @throws IOException if IE settings could not be obtained for some reason
 */
public static BrowserProxySettings lookupIEProxySettings() throws IOException {

    try {
        Vector addresses = new Vector();
        Vector proxies = new Vector();
        String proxyServerValue = null;
        String proxyOveride = null;

        /* Only use jRegistry if on Windows, running 1.3 or up Java
         * and NOT Windows Vista with JDK6.0 (because of jvm crash)
         */

        if (Utils.isSupportedJRE("+1.3") && Utils.isSupportedPlatform(
                "Windows") /*&&
                           !(Utils.isSupportedOSVersion("+6.0") && Utils.isSupportedJRE("+1.6"))*/) {

            /*
             * We can use jRegistryKey API to lookup IE settings in the
             * registry
             */
            //                RegistryKey key = new RegistryKey(RootKey.HKEY_CURRENT_USER,
            //                                "Software\\Microsoft\\Windows\\CurrentVersion\\Internet Settings"); //$NON-NLS-1$

            String proxyEnable = WinRegistry.getRegistryValue("user",
                    "Software\\Microsoft\\Windows\\CurrentVersion\\Internet Settings", "ProxyEnable", "0");
            if (proxyEnable != null) { //$NON-NLS-1$
                /*
                 * We have ProxyEnable so check to see if we are using a
                 * proxy
                 */
                if (proxyEnable.equals("1")) { //$NON-NLS-1$ //$NON-NLS-2$

                    proxyServerValue = WinRegistry.getRegistryValue("user",
                            "Software\\Microsoft\\Windows\\CurrentVersion\\Internet Settings", "ProxyServer",
                            null);
                    if (proxyServerValue != null) { //$NON-NLS-1$
                        /**
                         * We have some proxy settings. The values will be
                         * in the format "server.proxy.net:8888" or
                         */

                        proxyOveride = WinRegistry.getRegistryValue("user",
                                "Software\\Microsoft\\Windows\\CurrentVersion\\Internet Settings",
                                "ProxyOverride", null);
                    }
                } else {

                }
            }
        } else {
            if (System.getProperty("java.vendor").startsWith("Microsoft")) { //$NON-NLS-1$ //$NON-NLS-2$
                try {
                    Class clazz = Class.forName("com.ms.lang.RegKey"); //$NON-NLS-1$
                    int userRoot = clazz.getField("USER_ROOT").getInt(null); //$NON-NLS-1$
                    int keyOpenAll = clazz.getField("KEYOPEN_ALL").getInt(null); //$NON-NLS-1$
                    // #ifdef DEBUG
                    log.info(Messages.getString("ProxyUtil.lookingForRoot")); //$NON-NLS-1$
                    // #endif
                    Object rootKey = clazz.getMethod("getRootKey", new Class[] { int.class }).invoke(null, //$NON-NLS-1$
                            new Object[] { new Integer(userRoot) });
                    // #ifdef DEBUG
                    log.info(Messages.getString("ProxyUtil.getIERegistryKey")); //$NON-NLS-1$
                    // #endif
                    Object key = clazz.getConstructor(new Class[] { clazz, String.class, int.class })
                            .newInstance(new Object[] { rootKey,
                                    "Software\\Microsoft\\Windows\\CurrentVersion\\Internet Settings", //$NON-NLS-1$
                                    new Integer(keyOpenAll) });
                    // #ifdef DEBUG
                    log.info(Messages.getString("ProxyUtil.checkingIfProxyEnabled")); //$NON-NLS-1$
                    // #endif
                    if (((Integer) (clazz.getMethod("getIntValue", new Class[] { String.class }).invoke(key, //$NON-NLS-1$
                            new Object[] { "ProxyEnable" }))).intValue() == 1) { //$NON-NLS-1$
                        // #ifdef DEBUG
                        log.info(Messages.getString("ProxyUtil.gettingProxyServerList")); //$NON-NLS-1$
                        // #endif
                        proxyServerValue = (String) (clazz.getMethod("getStringValue", //$NON-NLS-1$
                                new Class[] { String.class, String.class })
                                .invoke(key, new Object[] { "ProxyServer", "" })); //$NON-NLS-1$ //$NON-NLS-2$
                        // #ifdef DEBUG
                        log.info(Messages.getString("ProxyUtil.gettingProxyOverides")); //$NON-NLS-1$
                        // #endif
                        proxyOveride = (String) (clazz
                                .getMethod("getStringValue", new Class[] { String.class, String.class }) //$NON-NLS-1$
                                .invoke(key, new Object[] { "ProxyOverride", "" })); //$NON-NLS-1$ //$NON-NLS-2$
                    }
                } catch (Throwable t) {
                    t.printStackTrace();
                }

            } else {
                // #ifdef DEBUG
                log.info(MessageFormat.format(Messages.getString("ProxyUtil.unsupportedJavaRuntime"), //$NON-NLS-1$
                        new Object[] { System.getProperty("java.version"), //$NON-NLS-1$
                                System.getProperty("java.vendor") })); //$NON-NLS-1$
                // #endif
            }

        }

        ProxyInfo p;

        if (proxyServerValue != null && proxyServerValue.indexOf(';') > -1) {
            /**
             * Format is multiple
             * "ftp=ftp.com:4444;gopher=gopher.com:3333;http=198.162.1.119:8888;https=https.com:2222;socks=socks.com:1111"
             */
            StringTokenizer tokens = new StringTokenizer(proxyServerValue, ";"); //$NON-NLS-1$

            while (tokens.hasMoreTokens()) {
                p = createProxyInfo(tokens.nextToken(), "IE Proxy Settings"); //$NON-NLS-1$
                proxies.addElement(p);
            }

        } else if (proxyServerValue != null) {
            /**
             * Format is single "http=server.proxy.net:8888" or
             * "server.proxy.net:8888"
             */
            p = createProxyInfo(proxyServerValue, "IE Proxy Settings"); //$NON-NLS-1$
            proxies.addElement(p);
        }

        BrowserProxySettings bps = new BrowserProxySettings();
        bps.setBrowser("Internet Explorer"); //$NON-NLS-1$
        bps.setProxies(new ProxyInfo[proxies.size()]);
        proxies.copyInto(bps.getProxies());
        if (proxyOveride != null) {

            StringTokenizer tokens = new StringTokenizer(proxyOveride, ";"); //$NON-NLS-1$

            while (tokens.hasMoreTokens()) {
                addresses.addElement(tokens.nextToken());
            }
        }

        bps.setBypassAddr(new String[addresses.size()]);
        addresses.copyInto(bps.getBypassAddr());
        return bps;

    } catch (Throwable t) {
        t.printStackTrace();
        throw new IOException(MessageFormat.format(Messages.getString("ProxyUtil.failedToLookupIEProxies"), //$NON-NLS-1$
                new Object[] { t.getMessage() }));
    }
}

From source file:com.ewcms.web.pubsub.PubsubServlet.java

private PubsubSenderable createPubsubSender(String path) {
    String name = null;/*ww  w . ja  v  a 2s . c  om*/
    if (StringUtils.indexOf(path, '/') == -1) {
        name = pathSender.get(path);
    } else {
        String root = StringUtils.substringBeforeLast(path, "/");
        name = pathSender.get(root);
        if (name == null) {
            String middle = StringUtils.substringAfter(root, "/");
            name = pathSender.get(middle);
        }
    }
    if (StringUtils.isNotBlank(name)) {
        try {
            Class<?> clazz = Class.forName(name);
            Class<?>[] argsClass = new Class<?>[] { String.class, ServletContext.class };
            Constructor<?> cons = clazz.getConstructor(argsClass);
            return (PubsubSenderable) cons.newInstance(new Object[] { path, this.getServletContext() });
        } catch (Exception e) {
            logger.error("PubsubSender create error:{}", e.toString());
        }
    }

    return new NoneSender();
}

From source file:com.scaleunlimited.cascading.DatumCompilerTest.java

@Test
public void testUUID() throws Exception {
    CompiledDatum result = DatumCompiler.generate(MyUUIDDatumTemplate.class);

    File baseDir = new File("build/test/DatumCompilerTest/testUUID/");
    FileUtils.deleteDirectory(baseDir);//from w w w.j  a  v  a 2 s  .co  m
    File srcDir = new File(baseDir, result.getPackageName().replaceAll("\\.", "/"));
    assertTrue(srcDir.mkdirs());

    File codeFile = new File(srcDir, result.getClassName() + ".java");
    OutputStream os = new FileOutputStream(codeFile);
    IOUtils.write(result.getClassCode(), os, "UTF-8");
    os.close();

    // Compile with Janino, give it a try. We have Janino since
    // it's a cascading dependency, but probably want to add a test
    // dependency on it.

    ClassLoader cl = new JavaSourceClassLoader(this.getClass().getClassLoader(), // parentClassLoader
            new File[] { baseDir }, // optionalSourcePath
            (String) null // optionalCharacterEncoding
    );

    // WARNING - we have to use xxxDatumTemplate as the base name, so that the code returned
    // by the compiler is for type xxxDatum. Otherwise when we try to load the class here,
    // we'll likely get the base (template) class, which will mask our generated class.
    Class clazz = cl.loadClass(result.getPackageName() + "." + result.getClassName());
    assertEquals("MyUUIDDatum", clazz.getSimpleName());

    Constructor c = clazz.getConstructor(UUID.class);
    BaseDatum datum = (BaseDatum) c.newInstance(UUID.randomUUID());

    // Verify that it can be serialized with Hadoop.
    // TODO figure out why Hadoop serializations aren't available???
    /*
    BasePlatform testPlatform = new HadoopPlatform(DatumCompilerTest.class);
    Tap tap = testPlatform.makeTap( testPlatform.makeBinaryScheme(datum.getFields()), 
                testPlatform.makePath("build/test/DatumCompilerTest/testSimpleSchema/"));
    TupleEntryCollector writer = tap.openForWrite(testPlatform.makeFlowProcess());
    writer.add(datum.getTuple());
    writer.close();
            
    TupleEntryIterator iter = tap.openForRead(testPlatform.makeFlowProcess());
    TupleEntry te = iter.next();
            
    // TODO how to test round-trip?
     */
}

From source file:org.crazydog.util.spring.ClassUtils.java

/**
 * Determine whether the given class has a public constructor with the given signature,
 * and return it if available (else return {@code null}).
 * <p>Essentially translates {@code NoSuchMethodException} to {@code null}.
 * @param clazz the clazz to analyze/*from   w  w w  .jav a2  s.  co m*/
 * @param paramTypes the parameter types of the method
 * @return the constructor, or {@code null} if not found
 * @see Class#getConstructor
 */
public static <T> Constructor<T> getConstructorIfAvailable(Class<T> clazz, Class<?>... paramTypes) {
    org.springframework.util.Assert.notNull(clazz, "Class must not be null");
    try {
        return clazz.getConstructor(paramTypes);
    } catch (NoSuchMethodException ex) {
        return null;
    }
}