/**
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF licenses this file to You under the Apache License, Version 2.0
* (the "License"); you may not use this file except in compliance with
* the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.apache.camel.util;
import java.io.Closeable;
import java.io.File;
import java.io.FileNotFoundException;
import java.io.IOException;
import java.io.InputStream;
import java.lang.annotation.Annotation;
import java.lang.reflect.AnnotatedElement;
import java.lang.reflect.Array;
import java.lang.reflect.Constructor;
import java.lang.reflect.Field;
import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Method;
import java.net.URL;
import java.nio.channels.ReadableByteChannel;
import java.nio.charset.Charset;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.Collection;
import java.util.Collections;
import java.util.Enumeration;
import java.util.Iterator;
import java.util.List;
import java.util.Locale;
import java.util.Map;
import java.util.NoSuchElementException;
import java.util.Properties;
import java.util.Scanner;
import org.w3c.dom.Node;
import org.w3c.dom.NodeList;
import org.apache.camel.CamelContext;
import org.apache.camel.CamelExecutionException;
import org.apache.camel.Exchange;
import org.apache.camel.Message;
import org.apache.camel.Ordered;
import org.apache.camel.RuntimeCamelException;
import org.apache.camel.TypeConverter;
import org.apache.camel.WrappedFile;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
/**
* A number of useful helper methods for working with Objects
*
* @version
*/
public final class ObjectHelper {
private static final Logger LOG = LoggerFactory.getLogger(ObjectHelper.class);
private static final String DEFAULT_DELIMITER = ",";
/**
* Utility classes should not have a public constructor.
*/
private ObjectHelper() {
}
/**
* A helper method for comparing objects for equality in which it uses type coercion to coerce
* types between the left and right values. This allows you test for equality for example with
* a String and Integer type as Camel will be able to coerce the types.
*/
public static boolean typeCoerceEquals(TypeConverter converter, Object leftValue, Object rightValue) {
// sanity check
if (leftValue == null && rightValue == null) {
// they are equal
return true;
} else if (leftValue == null || rightValue == null) {
// only one of them is null so they are not equal
return false;
}
// try without type coerce
boolean answer = equal(leftValue, rightValue);
if (answer) {
return true;
}
// are they same type, if so return false as the equals returned false
if (leftValue.getClass().isInstance(rightValue)) {
return false;
}
// convert left to right
Object value = converter.tryConvertTo(rightValue.getClass(), leftValue);
answer = equal(value, rightValue);
if (answer) {
return true;
}
// convert right to left
value = converter.tryConvertTo(leftValue.getClass(), rightValue);
answer = equal(leftValue, value);
return answer;
}
/**
* A helper method for comparing objects for inequality in which it uses type coercion to coerce
* types between the left and right values. This allows you test for inequality for example with
* a String and Integer type as Camel will be able to coerce the types.
*/
public static boolean typeCoerceNotEquals(TypeConverter converter, Object leftValue, Object rightValue) {
return !typeCoerceEquals(converter, leftValue, rightValue);
}
/**
* A helper method for comparing objects ordering in which it uses type coercion to coerce
* types between the left and right values. This allows you test for ordering for example with
* a String and Integer type as Camel will be able to coerce the types.
*/
@SuppressWarnings({"unchecked", "rawtypes"})
public static int typeCoerceCompare(TypeConverter converter, Object leftValue, Object rightValue) {
// if both values is numeric then compare using numeric
Long leftNum = converter.tryConvertTo(Long.class, leftValue);
Long rightNum = converter.tryConvertTo(Long.class, rightValue);
if (leftNum != null && rightNum != null) {
return leftNum.compareTo(rightNum);
}
// also try with floating point numbers
Double leftDouble = converter.tryConvertTo(Double.class, leftValue);
Double rightDouble = converter.tryConvertTo(Double.class, rightValue);
if (leftDouble != null && rightDouble != null) {
return leftDouble.compareTo(rightDouble);
}
// prefer to NOT coerce to String so use the type which is not String
// for example if we are comparing String vs Integer then prefer to coerce to Integer
// as all types can be converted to String which does not work well for comparison
// as eg "10" < 6 would return true, where as 10 < 6 will return false.
// if they are both String then it doesn't matter
if (rightValue instanceof String && (!(leftValue instanceof String))) {
// if right is String and left is not then flip order (remember to * -1 the result then)
return typeCoerceCompare(converter, rightValue, leftValue) * -1;
}
// prefer to coerce to the right hand side at first
if (rightValue instanceof Comparable) {
Object value = converter.tryConvertTo(rightValue.getClass(), leftValue);
if (value != null) {
return ((Comparable) rightValue).compareTo(value) * -1;
}
}
// then fallback to the left hand side
if (leftValue instanceof Comparable) {
Object value = converter.tryConvertTo(leftValue.getClass(), rightValue);
if (value != null) {
return ((Comparable) leftValue).compareTo(value);
}
}
// use regular compare
return compare(leftValue, rightValue);
}
/**
* A helper method for comparing objects for equality while handling nulls
*/
public static boolean equal(Object a, Object b) {
if (a == b) {
return true;
}
if (a instanceof byte[] && b instanceof byte[]) {
return equalByteArray((byte[])a, (byte[])b);
}
return a != null && b != null && a.equals(b);
}
/**
* A helper method for comparing byte arrays for equality while handling
* nulls
*/
public static boolean equalByteArray(byte[] a, byte[] b) {
if (a == b) {
return true;
}
// loop and compare each byte
if (a != null && b != null && a.length == b.length) {
for (int i = 0; i < a.length; i++) {
if (a[i] != b[i]) {
return false;
}
}
// all bytes are equal
return true;
}
return false;
}
/**
* Returns true if the given object is equal to any of the expected value
*/
public static boolean isEqualToAny(Object object, Object... values) {
for (Object value : values) {
if (equal(object, value)) {
return true;
}
}
return false;
}
/**
* A helper method for performing an ordered comparison on the objects
* handling nulls and objects which do not handle sorting gracefully
*/
public static int compare(Object a, Object b) {
return compare(a, b, false);
}
/**
* A helper method for performing an ordered comparison on the objects
* handling nulls and objects which do not handle sorting gracefully
*
* @param a the first object
* @param b the second object
* @param ignoreCase ignore case for string comparison
*/
@SuppressWarnings({"unchecked", "rawtypes"})
public static int compare(Object a, Object b, boolean ignoreCase) {
if (a == b) {
return 0;
}
if (a == null) {
return -1;
}
if (b == null) {
return 1;
}
if (a instanceof Ordered && b instanceof Ordered) {
return ((Ordered) a).getOrder() - ((Ordered) b).getOrder();
}
if (ignoreCase && a instanceof String && b instanceof String) {
return ((String) a).compareToIgnoreCase((String) b);
}
if (a instanceof Comparable) {
Comparable comparable = (Comparable)a;
return comparable.compareTo(b);
}
int answer = a.getClass().getName().compareTo(b.getClass().getName());
if (answer == 0) {
answer = a.hashCode() - b.hashCode();
}
return answer;
}
public static Boolean toBoolean(Object value) {
if (value instanceof Boolean) {
return (Boolean)value;
}
if (value instanceof String) {
return Boolean.valueOf((String)value);
}
if (value instanceof Integer) {
return (Integer)value > 0 ? Boolean.TRUE : Boolean.FALSE;
}
return null;
}
/**
* Asserts whether the value is <b>not</b> <tt>null</tt>
*
* @param value the value to test
* @param name the key that resolved the value
* @return the passed {@code value} as is
* @throws IllegalArgumentException is thrown if assertion fails
*/
public static <T> T notNull(T value, String name) {
if (value == null) {
throw new IllegalArgumentException(name + " must be specified");
}
return value;
}
/**
* Asserts whether the value is <b>not</b> <tt>null</tt>
*
* @param value the value to test
* @param on additional description to indicate where this problem occurred (appended as toString())
* @param name the key that resolved the value
* @return the passed {@code value} as is
* @throws IllegalArgumentException is thrown if assertion fails
*/
public static <T> T notNull(T value, String name, Object on) {
if (on == null) {
notNull(value, name);
} else if (value == null) {
throw new IllegalArgumentException(name + " must be specified on: " + on);
}
return value;
}
/**
* Asserts whether the string is <b>not</b> empty.
*
* @param value the string to test
* @param name the key that resolved the value
* @return the passed {@code value} as is
* @throws IllegalArgumentException is thrown if assertion fails
*/
public static String notEmpty(String value, String name) {
if (isEmpty(value)) {
throw new IllegalArgumentException(name + " must be specified and not empty");
}
return value;
}
/**
* Asserts whether the string is <b>not</b> empty.
*
* @param value the string to test
* @param on additional description to indicate where this problem occurred (appended as toString())
* @param name the key that resolved the value
* @return the passed {@code value} as is
* @throws IllegalArgumentException is thrown if assertion fails
*/
public static String notEmpty(String value, String name, Object on) {
if (on == null) {
notNull(value, name);
} else if (isEmpty(value)) {
throw new IllegalArgumentException(name + " must be specified and not empty on: " + on);
}
return value;
}
/**
* Tests whether the value is <tt>null</tt> or an empty string.
*
* @param value the value, if its a String it will be tested for text length as well
* @return true if empty
*/
public static boolean isEmpty(Object value) {
return !isNotEmpty(value);
}
/**
* Tests whether the value is <b>not</b> <tt>null</tt> or an empty string.
*
* @param value the value, if its a String it will be tested for text length as well
* @return true if <b>not</b> empty
*/
public static boolean isNotEmpty(Object value) {
if (value == null) {
return false;
} else if (value instanceof String) {
String text = (String) value;
return text.trim().length() > 0;
} else {
return true;
}
}
public static String[] splitOnCharacter(String value, String needle, int count) {
String rc[] = new String[count];
rc[0] = value;
for (int i = 1; i < count; i++) {
String v = rc[i - 1];
int p = v.indexOf(needle);
if (p < 0) {
return rc;
}
rc[i - 1] = v.substring(0, p);
rc[i] = v.substring(p + 1);
}
return rc;
}
/**
* Removes any starting characters on the given text which match the given
* character
*
* @param text the string
* @param ch the initial characters to remove
* @return either the original string or the new substring
*/
public static String removeStartingCharacters(String text, char ch) {
int idx = 0;
while (text.charAt(idx) == ch) {
idx++;
}
if (idx > 0) {
return text.substring(idx);
}
return text;
}
public static String capitalize(String text) {
if (text == null) {
return null;
}
int length = text.length();
if (length == 0) {
return text;
}
String answer = text.substring(0, 1).toUpperCase(Locale.ENGLISH);
if (length > 1) {
answer += text.substring(1, length);
}
return answer;
}
public static String after(String text, String after) {
if (!text.contains(after)) {
return null;
}
return text.substring(text.indexOf(after) + after.length());
}
public static String before(String text, String before) {
if (!text.contains(before)) {
return null;
}
return text.substring(0, text.indexOf(before));
}
public static String between(String text, String after, String before) {
text = after(text, after);
if (text == null) {
return null;
}
return before(text, before);
}
/**
* Returns true if the collection contains the specified value
*/
public static boolean contains(Object collectionOrArray, Object value) {
// favor String types
if (collectionOrArray != null && (collectionOrArray instanceof StringBuffer || collectionOrArray instanceof StringBuilder)) {
collectionOrArray = collectionOrArray.toString();
}
if (value != null && (value instanceof StringBuffer || value instanceof StringBuilder)) {
value = value.toString();
}
if (collectionOrArray instanceof Collection) {
Collection<?> collection = (Collection<?>)collectionOrArray;
return collection.contains(value);
} else if (collectionOrArray instanceof String && value instanceof String) {
String str = (String)collectionOrArray;
String subStr = (String)value;
return str.contains(subStr);
} else {
Iterator<Object> iter = createIterator(collectionOrArray);
while (iter.hasNext()) {
if (equal(value, iter.next())) {
return true;
}
}
}
return false;
}
/**
* Creates an iterator over the value if the value is a collection, an
* Object[], a String with values separated by comma,
* or a primitive type array; otherwise to simplify the caller's code,
* we just create a singleton collection iterator over a single value
* <p/>
* Will default use comma for String separating String values.
* This method does <b>not</b> allow empty values
*
* @param value the value
* @return the iterator
*/
public static Iterator<Object> createIterator(Object value) {
return createIterator(value, DEFAULT_DELIMITER);
}
/**
* Creates an iterator over the value if the value is a collection, an
* Object[], a String with values separated by the given delimiter,
* or a primitive type array; otherwise to simplify the caller's
* code, we just create a singleton collection iterator over a single value
* <p/>
* This method does <b>not</b> allow empty values
*
* @param value the value
* @param delimiter delimiter for separating String values
* @return the iterator
*/
public static Iterator<Object> createIterator(Object value, String delimiter) {
return createIterator(value, delimiter, false);
}
/**
* Creates an iterator over the value if the value is a collection, an
* Object[], a String with values separated by the given delimiter,
* or a primitive type array; otherwise to simplify the caller's
* code, we just create a singleton collection iterator over a single value
*
* </p> In case of primitive type arrays the returned {@code Iterator} iterates
* over the corresponding Java primitive wrapper objects of the given elements
* inside the {@code value} array. That's we get an autoboxing of the primitive
* types here for free as it's also the case in Java language itself.
*
* @param value the value
* @param delimiter delimiter for separating String values
* @param allowEmptyValues whether to allow empty values
* @return the iterator
*/
@SuppressWarnings("unchecked")
public static Iterator<Object> createIterator(Object value, String delimiter, final boolean allowEmptyValues) {
// if its a message than we want to iterate its body
if (value instanceof Message) {
value = ((Message) value).getBody();
}
if (value == null) {
return Collections.emptyList().iterator();
} else if (value instanceof Iterator) {
return (Iterator<Object>)value;
} else if (value instanceof Iterable) {
return ((Iterable<Object>)value).iterator();
} else if (value.getClass().isArray()) {
if (isPrimitiveArrayType(value.getClass())) {
final Object array = value;
return new Iterator<Object>() {
private int idx;
public boolean hasNext() {
return idx < Array.getLength(array);
}
public Object next() {
if (!hasNext()) {
throw new NoSuchElementException("no more element available for '" + array + "' at the index " + idx);
}
return Array.get(array, idx++);
}
public void remove() {
throw new UnsupportedOperationException();
}
};
} else {
List<Object> list = Arrays.asList((Object[]) value);
return list.iterator();
}
} else if (value instanceof NodeList) {
// lets iterate through DOM results after performing XPaths
final NodeList nodeList = (NodeList) value;
return new Iterator<Object>() {
private int idx;
public boolean hasNext() {
return idx < nodeList.getLength();
}
public Object next() {
if (!hasNext()) {
throw new NoSuchElementException("no more element available for '" + nodeList + "' at the index " + idx);
}
return nodeList.item(idx++);
}
public void remove() {
throw new UnsupportedOperationException();
}
};
} else if (value instanceof String) {
final String s = (String) value;
// this code is optimized to only use a Scanner if needed, eg there is a delimiter
if (delimiter != null && s.contains(delimiter)) {
// use a scanner if it contains the delimiter
Scanner scanner = new Scanner((String)value);
if (DEFAULT_DELIMITER.equals(delimiter)) {
// we use the default delimiter which is a comma, then cater for bean expressions with OGNL
// which may have balanced parentheses pairs as well.
// if the value contains parentheses we need to balance those, to avoid iterating
// in the middle of parentheses pair, so use this regular expression (a bit hard to read)
// the regexp will split by comma, but honor parentheses pair that may include commas
// as well, eg if value = "bean=foo?method=killer(a,b),bean=bar?method=great(a,b)"
// then the regexp will split that into two:
// -> bean=foo?method=killer(a,b)
// -> bean=bar?method=great(a,b)
// http://stackoverflow.com/questions/1516090/splitting-a-title-into-separate-parts
delimiter = ",(?!(?:[^\\(,]|[^\\)],[^\\)])+\\))";
}
scanner.useDelimiter(delimiter);
return CastUtils.cast(scanner);
} else {
// use a plain iterator that returns the value as is as there are only a single value
return new Iterator<Object>() {
private int idx;
public boolean hasNext() {
return idx == 0 && (allowEmptyValues || ObjectHelper.isNotEmpty(s));
}
public Object next() {
if (!hasNext()) {
throw new NoSuchElementException("no more element available for '" + s + "' at the index " + idx);
}
idx++;
return s;
}
public void remove() {
throw new UnsupportedOperationException();
}
};
}
} else {
return Collections.singletonList(value).iterator();
}
}
/**
* Returns the predicate matching boolean on a {@link List} result set where
* if the first element is a boolean its value is used otherwise this method
* returns true if the collection is not empty
*
* @return <tt>true</tt> if the first element is a boolean and its value
* is true or if the list is non empty
*/
public static boolean matches(List<?> list) {
if (!list.isEmpty()) {
Object value = list.get(0);
if (value instanceof Boolean) {
return (Boolean)value;
} else {
// lets assume non-empty results are true
return true;
}
}
return false;
}
/**
* A helper method to access a system property, catching any security exceptions
*
* @param name the name of the system property required
* @param defaultValue the default value to use if the property is not
* available or a security exception prevents access
* @return the system property value or the default value if the property is
* not available or security does not allow its access
*/
public static String getSystemProperty(String name, String defaultValue) {
try {
return System.getProperty(name, defaultValue);
} catch (Exception e) {
if (LOG.isDebugEnabled()) {
LOG.debug("Caught security exception accessing system property: " + name + ". Will use default value: " + defaultValue, e);
}
return defaultValue;
}
}
/**
* A helper method to access a boolean system property, catching any
* security exceptions
*
* @param name the name of the system property required
* @param defaultValue the default value to use if the property is not
* available or a security exception prevents access
* @return the boolean representation of the system property value or the
* default value if the property is not available or security does
* not allow its access
*/
public static boolean getSystemProperty(String name, Boolean defaultValue) {
String result = getSystemProperty(name, defaultValue.toString());
return Boolean.parseBoolean(result);
}
/**
* A helper method to access a camel context properties with a prefix
*
* @param prefix the prefix
* @param camelContext the camel context
* @return the properties which holds the camel context properties with the prefix,
* and the key omit the prefix part
*/
public static Properties getCamelPropertiesWithPrefix(String prefix, CamelContext camelContext) {
Properties answer = new Properties();
Map<String, String> camelProperties = camelContext.getProperties();
if (camelProperties != null) {
for (Map.Entry<String, String> entry : camelProperties.entrySet()) {
String key = entry.getKey();
if (key != null && key.startsWith(prefix)) {
answer.put(key.substring(prefix.length()), entry.getValue());
}
}
}
return answer;
}
/**
* Returns the type name of the given type or null if the type variable is
* null
*/
public static String name(Class<?> type) {
return type != null ? type.getName() : null;
}
/**
* Returns the type name of the given value
*/
public static String className(Object value) {
return name(value != null ? value.getClass() : null);
}
/**
* Returns the canonical type name of the given value
*/
public static String classCanonicalName(Object value) {
if (value != null) {
return value.getClass().getCanonicalName();
} else {
return null;
}
}
/**
* Attempts to load the given class name using the thread context class
* loader or the class loader used to load this class
*
* @param name the name of the class to load
* @return the class or <tt>null</tt> if it could not be loaded
*/
public static Class<?> loadClass(String name) {
return loadClass(name, ObjectHelper.class.getClassLoader());
}
/**
* Attempts to load the given class name using the thread context class
* loader or the given class loader
*
* @param name the name of the class to load
* @param loader the class loader to use after the thread context class loader
* @return the class or <tt>null</tt> if it could not be loaded
*/
public static Class<?> loadClass(String name, ClassLoader loader) {
return loadClass(name, loader, false);
}
/**
* Attempts to load the given class name using the thread context class
* loader or the given class loader
*
* @param name the name of the class to load
* @param loader the class loader to use after the thread context class loader
* @param needToWarn when <tt>true</tt> logs a warning when a class with the given name could not be loaded
* @return the class or <tt>null</tt> if it could not be loaded
*/
public static Class<?> loadClass(String name, ClassLoader loader, boolean needToWarn) {
// must clean the name so its pure java name, eg removing \n or whatever people can do in the Spring XML
name = normalizeClassName(name);
if (ObjectHelper.isEmpty(name)) {
return null;
}
// Try simple type first
Class<?> clazz = loadSimpleType(name);
if (clazz == null) {
// try context class loader
clazz = doLoadClass(name, Thread.currentThread().getContextClassLoader());
}
if (clazz == null) {
// then the provided loader
clazz = doLoadClass(name, loader);
}
if (clazz == null) {
// and fallback to the loader the loaded the ObjectHelper class
clazz = doLoadClass(name, ObjectHelper.class.getClassLoader());
}
if (clazz == null) {
if (needToWarn) {
LOG.warn("Cannot find class: " + name);
} else {
LOG.debug("Cannot find class: " + name);
}
}
return clazz;
}
/**
* Load a simple type
*
* @param name the name of the class to load
* @return the class or <tt>null</tt> if it could not be loaded
*/
//CHECKSTYLE:OFF
public static Class<?> loadSimpleType(String name) {
// special for byte[] or Object[] as its common to use
if ("java.lang.byte[]".equals(name) || "byte[]".equals(name)) {
return byte[].class;
} else if ("java.lang.Byte[]".equals(name) || "Byte[]".equals(name)) {
return Byte[].class;
} else if ("java.lang.Object[]".equals(name) || "Object[]".equals(name)) {
return Object[].class;
} else if ("java.lang.String[]".equals(name) || "String[]".equals(name)) {
return String[].class;
// and these is common as well
} else if ("java.lang.String".equals(name) || "String".equals(name)) {
return String.class;
} else if ("java.lang.Boolean".equals(name) || "Boolean".equals(name)) {
return Boolean.class;
} else if ("boolean".equals(name)) {
return boolean.class;
} else if ("java.lang.Integer".equals(name) || "Integer".equals(name)) {
return Integer.class;
} else if ("int".equals(name)) {
return int.class;
} else if ("java.lang.Long".equals(name) || "Long".equals(name)) {
return Long.class;
} else if ("long".equals(name)) {
return long.class;
} else if ("java.lang.Short".equals(name) || "Short".equals(name)) {
return Short.class;
} else if ("short".equals(name)) {
return short.class;
} else if ("java.lang.Byte".equals(name) || "Byte".equals(name)) {
return Byte.class;
} else if ("byte".equals(name)) {
return byte.class;
} else if ("java.lang.Float".equals(name) || "Float".equals(name)) {
return Float.class;
} else if ("float".equals(name)) {
return float.class;
} else if ("java.lang.Double".equals(name) || "Double".equals(name)) {
return Double.class;
} else if ("double".equals(name)) {
return double.class;
} else if ("java.lang.Character".equals(name) || "Character".equals(name)) {
return Character.class;
} else if ("char".equals(name)) {
return char.class;
}
return null;
}
//CHECKSTYLE:ON
/**
* Loads the given class with the provided classloader (may be null).
* Will ignore any class not found and return null.
*
* @param name the name of the class to load
* @param loader a provided loader (may be null)
* @return the class, or null if it could not be loaded
*/
private static Class<?> doLoadClass(String name, ClassLoader loader) {
ObjectHelper.notEmpty(name, "name");
if (loader == null) {
return null;
}
try {
LOG.trace("Loading class: {} using classloader: {}", name, loader);
return loader.loadClass(name);
} catch (ClassNotFoundException e) {
if (LOG.isTraceEnabled()) {
LOG.trace("Cannot load class: " + name + " using classloader: " + loader, e);
}
}
return null;
}
/**
* Attempts to load the given resource as a stream using the thread context
* class loader or the class loader used to load this class
*
* @param name the name of the resource to load
* @return the stream or null if it could not be loaded
*/
public static InputStream loadResourceAsStream(String name) {
InputStream in = null;
String resolvedName = resolveUriPath(name);
ClassLoader contextClassLoader = Thread.currentThread().getContextClassLoader();
if (contextClassLoader != null) {
in = contextClassLoader.getResourceAsStream(resolvedName);
}
if (in == null) {
in = ObjectHelper.class.getClassLoader().getResourceAsStream(resolvedName);
}
if (in == null) {
in = ObjectHelper.class.getResourceAsStream(resolvedName);
}
return in;
}
/**
* Attempts to load the given resource as a stream using the thread context
* class loader or the class loader used to load this class
*
* @param name the name of the resource to load
* @return the stream or null if it could not be loaded
*/
public static URL loadResourceAsURL(String name) {
URL url = null;
String resolvedName = resolveUriPath(name);
ClassLoader contextClassLoader = Thread.currentThread().getContextClassLoader();
if (contextClassLoader != null) {
url = contextClassLoader.getResource(resolvedName);
}
if (url == null) {
url = ObjectHelper.class.getClassLoader().getResource(resolvedName);
}
if (url == null) {
url = ObjectHelper.class.getResource(resolvedName);
}
return url;
}
/**
* Attempts to load the given resources from the given package name using the thread context
* class loader or the class loader used to load this class
*
* @param packageName the name of the package to load its resources
* @return the URLs for the resources or null if it could not be loaded
*/
public static Enumeration<URL> loadResourcesAsURL(String packageName) {
Enumeration<URL> url = null;
ClassLoader contextClassLoader = Thread.currentThread().getContextClassLoader();
if (contextClassLoader != null) {
try {
url = contextClassLoader.getResources(packageName);
} catch (IOException e) {
// ignore
}
}
if (url == null) {
try {
url = ObjectHelper.class.getClassLoader().getResources(packageName);
} catch (IOException e) {
// ignore
}
}
return url;
}
/**
* Helper operation used to remove relative path notation from
* resources. Most critical for resources on the Classpath
* as resource loaders will not resolve the relative paths correctly.
*
* @param name the name of the resource to load
* @return the modified or unmodified string if there were no changes
*/
private static String resolveUriPath(String name) {
// compact the path and use / as separator as that's used for loading resources on the classpath
return FileUtil.compactPath(name, '/');
}
/**
* A helper method to invoke a method via reflection and wrap any exceptions
* as {@link RuntimeCamelException} instances
*
* @param method the method to invoke
* @param instance the object instance (or null for static methods)
* @param parameters the parameters to the method
* @return the result of the method invocation
*/
public static Object invokeMethod(Method method, Object instance, Object... parameters) {
try {
return method.invoke(instance, parameters);
} catch (IllegalAccessException e) {
throw new RuntimeCamelException(e);
} catch (InvocationTargetException e) {
throw ObjectHelper.wrapRuntimeCamelException(e.getCause());
}
}
/**
* Tests whether the target method overrides the source method.
* <p/>
* Tests whether they have the same name, return type, and parameter list.
*
* @param source the source method
* @param target the target method
* @return <tt>true</tt> if it override, <tt>false</tt> otherwise
*/
public static boolean isOverridingMethod(Method source, Method target) {
if (source.getName().equals(target.getName())
&& source.getReturnType().equals(target.getReturnType())
&& source.getParameterTypes().length == target.getParameterTypes().length) {
// test if parameter types is the same as well
for (int i = 0; i < source.getParameterTypes().length; i++) {
if (!(source.getParameterTypes()[i].equals(target.getParameterTypes()[i]))) {
return false;
}
}
// the have same name, return type and parameter list, so its overriding
return true;
}
return false;
}
/**
* Returns a list of methods which are annotated with the given annotation
*
* @param type the type to reflect on
* @param annotationType the annotation type
* @return a list of the methods found
*/
public static List<Method> findMethodsWithAnnotation(Class<?> type,
Class<? extends Annotation> annotationType) {
return findMethodsWithAnnotation(type, annotationType, false);
}
/**
* Returns a list of methods which are annotated with the given annotation
*
* @param type the type to reflect on
* @param annotationType the annotation type
* @param checkMetaAnnotations check for meta annotations
* @return a list of the methods found
*/
public static List<Method> findMethodsWithAnnotation(Class<?> type,
Class<? extends Annotation> annotationType,
boolean checkMetaAnnotations) {
List<Method> answer = new ArrayList<Method>();
do {
Method[] methods = type.getDeclaredMethods();
for (Method method : methods) {
if (hasAnnotation(method, annotationType, checkMetaAnnotations)) {
answer.add(method);
}
}
type = type.getSuperclass();
} while (type != null);
return answer;
}
/**
* Checks if a Class or Method are annotated with the given annotation
*
* @param elem the Class or Method to reflect on
* @param annotationType the annotation type
* @param checkMetaAnnotations check for meta annotations
* @return true if annotations is present
*/
public static boolean hasAnnotation(AnnotatedElement elem, Class<? extends Annotation> annotationType,
boolean checkMetaAnnotations) {
if (elem.isAnnotationPresent(annotationType)) {
return true;
}
if (checkMetaAnnotations) {
for (Annotation a : elem.getAnnotations()) {
for (Annotation meta : a.annotationType().getAnnotations()) {
if (meta.annotationType().getName().equals(annotationType.getName())) {
return true;
}
}
}
}
return false;
}
/**
* Turns the given object arrays into a meaningful string
*
* @param objects an array of objects or null
* @return a meaningful string
*/
public static String asString(Object[] objects) {
if (objects == null) {
return "null";
} else {
StringBuilder buffer = new StringBuilder("{");
int counter = 0;
for (Object object : objects) {
if (counter++ > 0) {
buffer.append(", ");
}
String text = (object == null) ? "null" : object.toString();
buffer.append(text);
}
buffer.append("}");
return buffer.toString();
}
}
/**
* Returns true if a class is assignable from another class like the
* {@link Class#isAssignableFrom(Class)} method but which also includes
* coercion between primitive types to deal with Java 5 primitive type
* wrapping
*/
public static boolean isAssignableFrom(Class<?> a, Class<?> b) {
a = convertPrimitiveTypeToWrapperType(a);
b = convertPrimitiveTypeToWrapperType(b);
return a.isAssignableFrom(b);
}
/**
* Returns if the given {@code clazz} type is a Java primitive array type.
*
* @param clazz the Java type to be checked
* @return {@code true} if the given type is a Java primitive array type
*/
public static boolean isPrimitiveArrayType(Class<?> clazz) {
if (clazz != null && clazz.isArray()) {
return clazz.getComponentType().isPrimitive();
}
return false;
}
public static int arrayLength(Object[] pojo) {
return pojo.length;
}
/**
* Converts primitive types such as int to its wrapper type like
* {@link Integer}
*/
public static Class<?> convertPrimitiveTypeToWrapperType(Class<?> type) {
Class<?> rc = type;
if (type.isPrimitive()) {
if (type == int.class) {
rc = Integer.class;
} else if (type == long.class) {
rc = Long.class;
} else if (type == double.class) {
rc = Double.class;
} else if (type == float.class) {
rc = Float.class;
} else if (type == short.class) {
rc = Short.class;
} else if (type == byte.class) {
rc = Byte.class;
} else if (type == boolean.class) {
rc = Boolean.class;
} else if (type == char.class) {
rc = Character.class;
}
}
return rc;
}
/**
* Helper method to return the default character set name
*/
public static String getDefaultCharacterSet() {
return Charset.defaultCharset().name();
}
/**
* Returns the Java Bean property name of the given method, if it is a
* setter
*/
public static String getPropertyName(Method method) {
String propertyName = method.getName();
if (propertyName.startsWith("set") && method.getParameterTypes().length == 1) {
propertyName = propertyName.substring(3, 4).toLowerCase(Locale.ENGLISH) + propertyName.substring(4);
}
return propertyName;
}
/**
* Returns true if the given collection of annotations matches the given type
*/
public static boolean hasAnnotation(Annotation[] annotations, Class<?> type) {
for (Annotation annotation : annotations) {
if (type.isInstance(annotation)) {
return true;
}
}
return false;
}
/**
* Gets the annotation from the given instance.
*
* @param instance the instance
* @param type the annotation
* @return the annotation, or <tt>null</tt> if the instance does not have the given annotation
*/
public static <A extends java.lang.annotation.Annotation> A getAnnotation(Object instance, Class<A> type) {
return instance.getClass().getAnnotation(type);
}
/**
* Closes the given resource if it is available, logging any closing
* exceptions to the given log
*
* @param closeable the object to close
* @param name the name of the resource
* @param log the log to use when reporting closure warnings
* @deprecated will be removed in Camel 3.0. Instead use {@link org.apache.camel.util.IOHelper#close(java.io.Closeable, String, org.slf4j.Logger)} instead
*/
@Deprecated
public static void close(Closeable closeable, String name, Logger log) {
IOHelper.close(closeable, name, log);
}
/**
* Converts the given value to the required type or throw a meaningful exception
*/
@SuppressWarnings("unchecked")
public static <T> T cast(Class<T> toType, Object value) {
if (toType == boolean.class) {
return (T)cast(Boolean.class, value);
} else if (toType.isPrimitive()) {
Class<?> newType = convertPrimitiveTypeToWrapperType(toType);
if (newType != toType) {
return (T)cast(newType, value);
}
}
try {
return toType.cast(value);
} catch (ClassCastException e) {
throw new IllegalArgumentException("Failed to convert: "
+ value + " to type: " + toType.getName() + " due to: " + e, e);
}
}
/**
* A helper method to create a new instance of a type using the default
* constructor arguments.
*/
public static <T> T newInstance(Class<T> type) {
try {
return type.newInstance();
} catch (InstantiationException e) {
throw new RuntimeCamelException(e);
} catch (IllegalAccessException e) {
throw new RuntimeCamelException(e);
}
}
/**
* A helper method to create a new instance of a type using the default
* constructor arguments.
*/
public static <T> T newInstance(Class<?> actualType, Class<T> expectedType) {
try {
Object value = actualType.newInstance();
return cast(expectedType, value);
} catch (InstantiationException e) {
throw new RuntimeCamelException(e);
} catch (IllegalAccessException e) {
throw new RuntimeCamelException(e);
}
}
/**
* Does the given class have a default public no-arg constructor.
*/
public static boolean hasDefaultPublicNoArgConstructor(Class<?> type) {
// getConstructors() returns only public constructors
for (Constructor<?> ctr : type.getConstructors()) {
if (ctr.getParameterTypes().length == 0) {
return true;
}
}
return false;
}
/**
* Returns true if the given name is a valid java identifier
*/
public static boolean isJavaIdentifier(String name) {
if (name == null) {
return false;
}
int size = name.length();
if (size < 1) {
return false;
}
if (Character.isJavaIdentifierStart(name.charAt(0))) {
for (int i = 1; i < size; i++) {
if (!Character.isJavaIdentifierPart(name.charAt(i))) {
return false;
}
}
return true;
}
return false;
}
/**
* Returns the type of the given object or null if the value is null
*/
public static Object type(Object bean) {
return bean != null ? bean.getClass() : null;
}
/**
* Evaluate the value as a predicate which attempts to convert the value to
* a boolean otherwise true is returned if the value is not null
*/
public static boolean evaluateValuePredicate(Object value) {
if (value instanceof Boolean) {
return (Boolean)value;
} else if (value instanceof String) {
if ("true".equalsIgnoreCase((String)value)) {
return true;
} else if ("false".equalsIgnoreCase((String)value)) {
return false;
}
} else if (value instanceof NodeList) {
// is it an empty dom with empty attributes
if (value instanceof Node && ((Node)value).hasAttributes()) {
return true;
}
NodeList list = (NodeList) value;
return list.getLength() > 0;
} else if (value instanceof Collection) {
// is it an empty collection
Collection<?> col = (Collection<?>) value;
return col.size() > 0;
}
return value != null;
}
/**
* Wraps the caused exception in a {@link RuntimeCamelException} if its not
* already such an exception.
*
* @param e the caused exception
* @return the wrapper exception
*/
public static RuntimeCamelException wrapRuntimeCamelException(Throwable e) {
if (e instanceof RuntimeCamelException) {
// don't double wrap
return (RuntimeCamelException)e;
} else {
return new RuntimeCamelException(e);
}
}
/**
* Wraps the caused exception in a {@link CamelExecutionException} if its not
* already such an exception.
*
* @param e the caused exception
* @return the wrapper exception
*/
public static CamelExecutionException wrapCamelExecutionException(Exchange exchange, Throwable e) {
if (e instanceof CamelExecutionException) {
// don't double wrap
return (CamelExecutionException)e;
} else {
return new CamelExecutionException("Exception occurred during execution", exchange, e);
}
}
/**
* Cleans the string to a pure Java identifier so we can use it for loading class names.
* <p/>
* Especially from Spring DSL people can have \n \t or other characters that otherwise
* would result in ClassNotFoundException
*
* @param name the class name
* @return normalized classname that can be load by a class loader.
*/
public static String normalizeClassName(String name) {
StringBuilder sb = new StringBuilder(name.length());
for (char ch : name.toCharArray()) {
if (ch == '.' || ch == '[' || ch == ']' || ch == '-' || Character.isJavaIdentifierPart(ch)) {
sb.append(ch);
}
}
return sb.toString();
}
/**
* Creates an iterator to walk the exception from the bottom up
* (the last caused by going upwards to the root exception).
*
* @param exception the exception
* @return the iterator
*/
public static Iterator<Throwable> createExceptionIterator(Throwable exception) {
return new ExceptionIterator(exception);
}
/**
* Retrieves the given exception type from the exception.
* <p/>
* Is used to get the caused exception that typically have been wrapped in some sort
* of Camel wrapper exception
* <p/>
* The strategy is to look in the exception hierarchy to find the first given cause that matches the type.
* Will start from the bottom (the real cause) and walk upwards.
*
* @param type the exception type wanted to retrieve
* @param exception the caused exception
* @return the exception found (or <tt>null</tt> if not found in the exception hierarchy)
*/
public static <T> T getException(Class<T> type, Throwable exception) {
if (exception == null) {
return null;
}
// walk the hierarchy and look for it
Iterator<Throwable> it = createExceptionIterator(exception);
while (it.hasNext()) {
Throwable e = it.next();
if (type.isInstance(e)) {
return type.cast(e);
}
}
// not found
return null;
}
/**
* Creates a {@link Scanner} for scanning the given value.
*
* @param exchange the current exchange
* @param value the value, typically the message IN body
* @return the scanner, is newer <tt>null</tt>
*/
public static Scanner getScanner(Exchange exchange, Object value) {
if (value instanceof WrappedFile) {
// generic file is just a wrapper for the real file so call again with the real file
WrappedFile<?> gf = (WrappedFile<?>) value;
return getScanner(exchange, gf.getFile());
}
String charset = exchange.getProperty(Exchange.CHARSET_NAME, String.class);
Scanner scanner = null;
if (value instanceof Readable) {
scanner = new Scanner((Readable)value);
} else if (value instanceof InputStream) {
scanner = charset == null ? new Scanner((InputStream)value) : new Scanner((InputStream)value, charset);
} else if (value instanceof File) {
try {
scanner = charset == null ? new Scanner((File)value) : new Scanner((File)value, charset);
} catch (FileNotFoundException e) {
throw new RuntimeCamelException(e);
}
} else if (value instanceof String) {
scanner = new Scanner((String)value);
} else if (value instanceof ReadableByteChannel) {
scanner = charset == null ? new Scanner((ReadableByteChannel)value) : new Scanner((ReadableByteChannel)value, charset);
}
if (scanner == null) {
// value is not a suitable type, try to convert value to a string
String text = exchange.getContext().getTypeConverter().convertTo(String.class, exchange, value);
if (text != null) {
scanner = new Scanner(text);
}
}
if (scanner == null) {
scanner = new Scanner("");
}
return scanner;
}
public static String getIdentityHashCode(Object object) {
return "0x" + Integer.toHexString(System.identityHashCode(object));
}
/**
* Lookup the constant field on the given class with the given name
*
* @param clazz the class
* @param name the name of the field to lookup
* @return the value of the constant field, or <tt>null</tt> if not found
*/
public static String lookupConstantFieldValue(Class<?> clazz, String name) {
if (clazz == null) {
return null;
}
// remove leading dots
if (name.startsWith(",")) {
name = name.substring(1);
}
for (Field field : clazz.getFields()) {
if (field.getName().equals(name)) {
try {
Object v = field.get(null);
return v.toString();
} catch (IllegalAccessException e) {
// ignore
return null;
}
}
}
return null;
}
/**
* Is the given value a numeric NaN type
*
* @param value the value
* @return <tt>true</tt> if its a {@link Float#NaN} or {@link Double#NaN}.
*/
public static boolean isNaN(Object value) {
if (value == null || !(value instanceof Number)) {
return false;
}
// value must be a number
return value.equals(Float.NaN) || value.equals(Double.NaN);
}
private static final class ExceptionIterator implements Iterator<Throwable> {
private List<Throwable> tree = new ArrayList<Throwable>();
private Iterator<Throwable> it;
public ExceptionIterator(Throwable exception) {
Throwable current = exception;
// spool to the bottom of the caused by tree
while (current != null) {
tree.add(current);
current = current.getCause();
}
// reverse tree so we go from bottom to top
Collections.reverse(tree);
it = tree.iterator();
}
public boolean hasNext() {
return it.hasNext();
}
public Throwable next() {
return it.next();
}
public void remove() {
it.remove();
}
}
}