Example usage for java.lang NullPointerException NullPointerException

Introduction

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

Prototype

public NullPointerException(String s)

Source Link

Document

Constructs a NullPointerException with the specified detail message.

Usage

From source file:Main.java

/**
 * Get a list of all threads in a thread group. An empty array is returned
 * if there are no threads in the group.
 * /*from  w  ww .  j  a v  a2  s  .  c  o  m*/
 * @param group
 *        the thread group to list
 * @return an array of threads
 * @throws NullPointerException
 *         if the group is null
 */
public static Thread[] getGroupThreads(final ThreadGroup group) {
    if (group == null) {
        throw new NullPointerException("Null group");
    }
    int nAlloc = group.activeCount();
    int n = 0;
    Thread[] threads = null;
    do {
        nAlloc *= 2;
        threads = new Thread[nAlloc];
        n = group.enumerate(threads, false);
    } while (n == nAlloc);
    return java.util.Arrays.copyOf(threads, n);
}

From source file:jef.tools.Assert.java

/**
 * ?null/*from   w  w w  .ja v  a 2 s.  co  m*/
 * @param obj
 */
public static void notNull(Object obj) {
    if (obj == null)
        throw new NullPointerException("The input parameter must not be null!");
}

From source file:Main.java

/**
 * Get the thread group with the given name. A null is returned if no such
 * group is found. If more than one group has the same name, the first one
 * found is returned./*from   w  w  w .ja  v  a  2  s  . c  o  m*/
 * 
 * @param name
 *        the thread group name to search for
 * @return the thread group, or null if not found
 * @throws NullPointerException
 *         if the name is null
 */
public static ThreadGroup getThreadGroup(final String name) {
    if (name == null) {
        throw new NullPointerException("Null name");
    }
    final ThreadGroup[] groups = getAllThreadGroups();
    for (ThreadGroup group : groups) {
        if (group.getName().equals(name))
            return group;
    }
    return null;
}

From source file:com.qait.automation.samjbehavedemo.utils.FileHandler.java

public static List<String> getFileNames(String filedirpath, final String filenameendswith) {

    List<String> filenames = new ArrayList<>();

    File[] files = getFile(filedirpath).listFiles();

    for (File file : files) {
        String filename = file.getName();
        if (file.isFile() && filename.toLowerCase().endsWith(filenameendswith.toLowerCase())) {
            filenames.add(filename);/*  w  ww.  j  ava2 s. co  m*/
        }
    }

    if (filenames.isEmpty()) {
        throw new NullPointerException(
                "There are no files matching the criteria in directoy: " + filedirpath.toUpperCase());
    }

    return filenames;
}

From source file:edu.cornell.mannlib.vitro.webapp.filestorage.TempFileHolder.java

/**
 * Create a {@link TempFileHolder} holding the given {@link FileInfo}, and
 * attach it to the session with the given attribute name.
 * //from  www . ja  va2  s  . c  o m
 * If an attribute with this name already exists, it is replaced.
 */
public static void attach(HttpSession session, String attributeName, FileInfo fileInfo) {
    if (session == null) {
        throw new NullPointerException("session may not be null.");
    }
    if (attributeName == null) {
        throw new NullPointerException("attributeName may not be null.");
    }
    if (fileInfo == null) {
        throw new NullPointerException("fileInfo may not be null.");
    }
    log.debug("attach this file: " + fileInfo);
    session.setAttribute(attributeName, new TempFileHolder(fileInfo));
}

From source file:Main.java

/**
 * Gets all threads if its name matches a regular expression.  For example,
 * using a regex of "main" will execute a case-sensitive match for threads
 * with the exact name of "main".  A regex of ".*main.*" will execute a
 * case sensitive match for threads with "main" anywhere in their name. A
 * regex of "(?i).*main.*" will execute a case insensitive match of any
 * thread that has "main" in its name.// www.j a  v  a 2  s.  co  m
 * @param regex The regular expression to use when matching a threads name.
 *      Same rules apply as String.matches() method.
 * @return An array (will not be null) of all matching threads.  An empty
 *      array will be returned if no threads match.
 */
static public Thread[] getAllThreadsMatching(final String regex) {
    if (regex == null)
        throw new NullPointerException("Null thread name regex");
    final Thread[] threads = getAllThreads();
    ArrayList<Thread> matchingThreads = new ArrayList<Thread>();
    for (Thread thread : threads) {
        if (thread.getName().matches(regex)) {
            matchingThreads.add(thread);
        }
    }
    return matchingThreads.toArray(new Thread[0]);
}

From source file:edu.cornell.mannlib.vitro.webapp.config.ConfigurationProperties.java

public static ConfigurationProperties getBean(ServletRequest request) {
    if (request == null) {
        throw new NullPointerException("request may not be null.");
    }/*from  w w w.j  a  v a2s. c om*/
    if (!(request instanceof HttpServletRequest)) {
        throw new IllegalArgumentException("request must be an HttpServletRequest");
    }
    HttpServletRequest httpRequest = (HttpServletRequest) request;
    return getBean(httpRequest.getSession());
}

From source file:Main.java

/**
 * Ensures that an object reference passed as a parameter to the calling
 * method is not null./*  w ww.  jav  a  2s . co m*/
 *
 * @param reference an object reference
 * @param errorMessage the exception message to use if the check fails; will
 *     be converted to a string using {@link String#valueOf(Object)}
 * @return the non-null reference that was validated
 * @throws NullPointerException if {@code reference} is null
 */
public static <T> T checkNotNull(T reference, Object errorMessage) {
    if (reference == null) {
        throw new NullPointerException(String.valueOf(errorMessage));
    }
    return reference;
}

From source file:br.bireme.mlts.utils.Document2JSON.java

public static Map<String, List<Fieldable>> getMap(final Document doc) {
    if (doc == null) {
        throw new NullPointerException("doc");
    }/*from ww  w. j a va  2  s .  c  o  m*/

    final Map<String, List<Fieldable>> ret = new LinkedHashMap<String, List<Fieldable>>();
    final List<Fieldable> fields = doc.getFields();
    for (Fieldable fld : fields) {
        List<Fieldable> lfld = ret.get(fld.name());
        if (lfld == null) {
            lfld = new ArrayList<Fieldable>();
            ret.put(fld.name(), lfld);
        }
        lfld.add(fld);
    }

    return ret;
}

From source file:fr.univlorraine.mondossierweb.utils.PropertyUtils.java

/** Retourne l'url de serveur elasticSearch */
public static String getElasticSearchUrl() {
    String value = System.getProperty("context.param.elasticsearch.url");
    if (!StringUtils.hasText(value))
        throw new NullPointerException("param.elasticsearch.url cannot be null !");
    return value;
}