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java.lang.Objectorg.flexdock.util.Utilities
public class Utilities
| Field Summary | |
|---|---|
static boolean |
JAVA_1_4
A constant representing the Java version. |
static boolean |
JAVA_1_5
A constant representing the Java version. |
| Method Summary | |
|---|---|
static Object |
createInstance(String className)
Creates and returns an instance of the specified class name using Class.newInstance(). |
static Object |
createInstance(String className,
boolean failSilent)
Creates and returns an instance of the specified class name using Class.newInstance(). |
static Object |
createInstance(String className,
Class superType)
Creates and returns an instance of the specified class name using Class.newInstance(). |
static Object |
createInstance(String className,
Class superType,
boolean failSilent)
Creates and returns an instance of the specified class name using Class.newInstance(). |
static float |
getFloat(String data,
float defaultValue)
Returns a float value for the specified String. |
static Object |
getInstance(String className)
Returns an instance of the specified class name. |
static Object |
getInstance(String className,
boolean failSilent)
Returns an instance of the specified class name. |
static int |
getInt(String data)
Returns an int value for the specified String. |
static int |
getInt(String data,
int defaultValue)
Returns an int value for the specified String. |
static Object |
getValue(Object obj,
String fieldName)
Returns the value of the specified fieldName within the specified
Object. |
static boolean |
isChanged(Object oldObj,
Object newObj)
Checks for inequality between the two specified Objects. |
static boolean |
isEmpty(String data)
Returns true if the specified String is null or
contains only whitespace. |
static boolean |
isEqual(Object obj1,
Object obj2)
Checks for equality between the two specified Objects. |
static void |
put(Map map,
Object key,
Object value)
Puts the supplied value into the specified Map using the
specified key. |
static boolean |
setValue(Object obj,
String fieldName,
Object value)
Returns the value of the specified fieldName within the specified
Object. |
static void |
sleep(long millis)
Puts the current Thread to sleep for the specified timeout. |
static boolean |
sysTrue(String key)
Deprecated. Use Boolean.getBoolean(String). |
| Methods inherited from class java.lang.Object |
|---|
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait |
| Field Detail |
|---|
public static final boolean JAVA_1_4
true
if the version is 1.4.
public static final boolean JAVA_1_5
true
if the version is 1.5.
| Method Detail |
|---|
public static int getInt(String data)
int value for the specified String. This
method calls Integer.parseInt(String s) and returns the resulting
int value. If any Exception is thrown, this method
returns a value of 0.
data - a String containing the int representation to
be parsed
getInt(String, int),
Integer.parseInt(java.lang.String)
public static int getInt(String data,
int defaultValue)
int value for the specified String. This
method calls Integer.parseInt(String s) and returns the resulting
int value. If any Exception is thrown, this method
returns the value supplied by the defaultValue parameter.
data - a String containing the int representation to
be parseddefaultValue - the value to return if an Exception is encountered.
Integer.parseInt(java.lang.String)
public static float getFloat(String data,
float defaultValue)
float value for the specified String. This
method calls Float.parseFloat(String s) and returns the resulting
float value. If any Exception is thrown by
parseFloat, this method returns the value supplied by the
defaultValue parameter.
data - a String containing the float representation
to be parseddefaultValue - the value to return if an Exception is encountered on
the underlying parse mechanism.
Float.parseFloat(java.lang.String)public static boolean isEmpty(String data)
true if the specified String is null or
contains only whitespace. Otherwise, returns false. The
whitespace check is performed by calling trim() and checking to
see if the trimmed string length() is zero.
data - the String to check for non-whitespace content
true if the specified String is null or
contains only whitespace, false otherwise.public static Object getInstance(String className)
className is
null, then this method returns a null reference.
This method will try two different means of obtaining an instance of
className. First, it will attempt to resolve the Class
of className via Class.forName(String className). It
will then use reflection to search for a method on the class named
"getInstance()". If the method is found, then it is invoked and
the object instance is returned.
If there are any problems encountered while attempting to invoke
getInstance() on the specified class, the Throwable is
caught and this method dispatches to
createInstance(String className, boolean failSilent) with an
argument of false for failSilent.
createInstance(String className, boolean failSilent) will attempt
to invoke newInstance() on the Class for the specified
class name. If any Throwable is encountered during this process,
the value of false for failSilent will cause the stack
trace to be printed to the System.err and a null
reference will be returned.
className - the fully qualified name of the desired class.
getInstance(String, boolean),
createInstance(String, boolean),
Class.forName(java.lang.String),
Class.getMethod(java.lang.String, java.lang.Class[]),
Method.invoke(java.lang.Object, java.lang.Object[]),
Class.newInstance()
public static Object getInstance(String className,
boolean failSilent)
className is
null, then this method returns a null reference.
This method will try two different means of obtaining an instance of
className. First, it will attempt to resolve the Class
of className via Class.forName(String className). It
will then use reflection to search for a method on the class named
"getInstance()". If the method is found, then it is invoked and
the object instance is returned.
If there are any problems encountered while attempting to invoke
getInstance() on the specified class, the Throwable is
caught and this method dispatches to
createInstance(String className, boolean failSilent), passing
the specified value for failSilent.
createInstance(String className, boolean failSilent) will attempt
to invoke newInstance() on the Class for the specified
class name. If any Throwable is encountered during this process,
the value of failSilent is checked to determine whether the stack
stack trace should be printed to the System.err. A null
reference will be returned if any problems are encountered.
className - the fully qualified name of the desired class.failSilent - true if the stack trace should not be printed
to the System.err when a Throwable is caught,
false otherwise.
createInstance(String, boolean),
Class.forName(java.lang.String),
Class.getMethod(java.lang.String, java.lang.Class[]),
Method.invoke(java.lang.Object, java.lang.Object[]),
Class.newInstance()public static Object createInstance(String className)
Class.newInstance(). If className is null, then
this method returns a null reference. This dispatches to
createInstance(String className, Class superType, boolean failSilent)
with an argument of null for superType and false
for failSilent.
This method will attempt to resolve the Class of
className via Class.forName(String className). No class
assignability checkes are performed because this method uses a
null superType.
Once the desired class has been resolved, a new instance of it is created
and returned by invoking its newInstance() method. If there are
any problems encountered during this process, the value of false
for failSilent will ensure the stack stack trace is be printed to
the System.err. A null reference will be returned if any
problems are encountered.
className - the fully qualified name of the desired class.
createInstance(String, Class, boolean),
Class.forName(java.lang.String),
Class.newInstance()
public static Object createInstance(String className,
boolean failSilent)
Class.newInstance(). If className is null, then
this method returns a null reference. The failSilent
parameter will determine whether error stack traces should be reported to
the System.err before this method returns null. This
method dispatches to
createInstance(String className, Class superType, boolean failSilent)
with an argument of null for superType.
This method will attempt to resolve the Class of
className via Class.forName(String className). No class
assignability checkes are performed because this method uses a
null superType.
Once the desired class has been resolved, a new instance of it is created
and returned by invoking its newInstance() method. If there are
any problems encountered during this process, the value of
failSilent is checked to determine whether the stack stack trace
should be printed to the System.err. A null reference
will be returned if any problems are encountered.
className - the fully qualified name of the desired class.failSilent - true if the stack trace should not be printed
to the System.err when a Throwable is caught,
false otherwise.
createInstance(String, Class, boolean),
Class.forName(java.lang.String),
Class.newInstance()
public static Object createInstance(String className,
Class superType)
Class.newInstance(). If className is null, then
this method returns a null reference. If superType is
non-null, then this method will enforce polymorphic identity
via Class.isAssignableFrom(Class cls). This method dispatches to
createInstance(String className, Class superType, boolean failSilent)
with an argument of false for failSilent.
This method will attempt to resolve the Class of
className via Class.forName(String className). If
superType is non-null, then class identity is checked
by calling superType.isAssignableFrom(c) to ensure the resolved
class is an valid equivalent, descendent, or implementation of the
specified className. If this check fails, then a
ClassCastException is thrown and caught internally and this
method returns null. If superType is null, then
no assignability checks are performed on the resolved class.
Once the desired class has been resolved, a new instance of it is created
and returned by invoking its newInstance() method. If there are
any problems encountered during this process, the value of false
for failSilent will ensure the stack stack trace is be printed to
the System.err. A null reference will be returned if any
problems are encountered.
className - the fully qualified name of the desired class.superType - optional paramter used as a means of enforcing the inheritance
hierarchy
createInstance(String, Class, boolean),
Class.forName(java.lang.String),
Class.isAssignableFrom(java.lang.Class),
Class.newInstance()
public static Object createInstance(String className,
Class superType,
boolean failSilent)
Class.newInstance(). If className is null, then
this method returns a null reference. If superType is
non-null, then this method will enforce polymorphic identity
via Class.isAssignableFrom(Class cls). The failSilent
parameter will determine whether error stack traces should be reported to
the System.err before this method returns null.
This method will attempt to resolve the Class of
className via Class.forName(String className). If
superType is non-null, then class identity is checked
by calling superType.isAssignableFrom(c) to ensure the resolved
class is an valid equivalent, descendent, or implementation of the
specified className. If this check fails, then a
ClassCastException is thrown and caught internally and this
method returns null. If superType is null, then
no assignability checks are performed on the resolved class.
Once the desired class has been resolved, a new instance of it is created
and returned by invoking its newInstance() method. If there are
any problems encountered during this process, the value of
failSilent is checked to determine whether the stack stack trace
should be printed to the System.err. A null reference
will be returned if any problems are encountered.
className - the fully qualified name of the desired class.superType - optional paramter used as a means of enforcing the inheritance
hierarchyfailSilent - true if the stack trace should not be printed
to the System.err when a Throwable is caught,
false otherwise.
Class.forName(java.lang.String),
Class.isAssignableFrom(java.lang.Class),
Class.newInstance()
public static boolean isEqual(Object obj1,
Object obj2)
Objects. If both
arguments are the same Object reference using an ==
relationship, then this method returns true. Failing that check,
if either of the arguments is null, then the other must not be
and this method returns false. Finally, if both arguments are
non-null with different Object references, then this
method returns the value of obj1.equals(obj2).
This method is the exact opposite of
isChanged(Object oldObj, Object newObj).
obj1 - the first Object to be checked for equalityobj2 - the second Object to be checked for equality
true if the Objects are equal, false
otherwise.isChanged(Object, Object),
Object.equals(java.lang.Object)
public static boolean isChanged(Object oldObj,
Object newObj)
Objects. If both
arguments are the same Object reference using an ==
relationship, then this method returns false. Failing that
check, if either of the arguments is null, then the other must
not be and this method returns true. Finally, if both arguments
are non-null with different Object references, then this
method returns the opposite value of obj1.equals(obj2).
This method is the exact opposite of
isEqual(Object obj1, Object obj2).
oldObj - the first Object to be checked for inequalitynewObj - the second Object to be checked for inequality
false if the Objects are equal, true
otherwise.isEqual(Object, Object),
Object.equals(java.lang.Object)public static boolean sysTrue(String key)
Boolean.getBoolean(String).
true if there is currently a System property with
the specified key whose value is "true". If the System
property does not exist, or the value is inequal to "true", this method
returns false. This method returns false if the
specified key parameter is null.
key - the System property to test.
true if there is currently a System property with
the specified key whose value is "true".System.getProperty(java.lang.String),
String.equals(java.lang.Object)
public static void put(Map map,
Object key,
Object value)
value into the specified Map using the
specified key. This is a convenience method to automate
null-checks. A value parameter of null is interpreted as
a removal from the specified Map rather than an put
operation.
If either map or key are null then this method
returns with no action taken. If value is null,
then this method calls map.remove(key). Otherwise, this method
calls map.put(key, value).
map - the Map whose contents is to be modifiedkey - with which the specified value is to be associated.value - value to be associated with the specified key.Map.put(java.lang.Object, java.lang.Object),
Map.remove(java.lang.Object)
public static boolean setValue(Object obj,
String fieldName,
Object value)
fieldName within the specified
Object. This is a convenience method for reflection hacks to
retrieve the value of protected, private, or package-private field
members while hiding the boilerplate reflection code within a single
utility method call. This method will return true if the
operation was successful and false if errors were encountered.
This method calls obj.getClass() to retrieve the Class of
the specified Object. It then retrieves the desired field by
calling the classes' getDeclaredField(String name) method,
passing the specified field name. If the field is deemed inaccessible via
it's isAccessible() method, then it is made accessible by calling
setAccessible(true). The field value is set by invoking the
field's set(Object obj, Object value) method and passing the
original Object and value parameter as arguments. Before
returning, the field's accessibility is reset to its original state.
If either obj or fieldName are null, then this
method returns false.
It should be understood that this method will not function properly for
inaccessible fields in the presence of a SecurityManager. Nor
will it function properly for non-existent fields (if a field called
fieldName does not exist on the class). All Throwables
encountered by this method will be caught and eaten and the method will
return false. This works under the assumption that the operation
might likely fail because the method itself is, in reality, a convenience
hack. Therefore, specifics of any generated errors on the call stack are
discarded and only the final outcome (true/false of the
operation is deemed relevant. If call stack data is required within
the application for any thrown exceptions, then this method should not be
used.}
obj - the object for which the represented field's value is to be
modifiedfieldName - the name of the field to be setvalue - the new value for the field of obj being modifiedObject.getClass(),
Class.getDeclaredField(java.lang.String),
AccessibleObject.isAccessible(),
AccessibleObject.setAccessible(boolean),
Field.set(Object, Object)
public static Object getValue(Object obj,
String fieldName)
throws IllegalAccessException
fieldName within the specified
Object. This is a convenience method for reflection hacks to
retrieve the value of protected, private, or package-private field
members while hiding the boilerplate reflection code within a single
utility method call.
This method calls obj.getClass() to retrieve the Class of
the specified Object. It then retrieves the desired field by
calling the classes' getDeclaredField(String name) method,
passing the specified field name. If the field is deemed inaccessible via
it's isAccessible() method, then it is made accessible by calling
setAccessible(true). The return value is retrieved by invoking
the field's get(Object obj) method and passing the original
Object parameter as an argument. Before returning, the field's
accessibility is reset to its original state.
If either obj or fieldName are null, then this
method returns null.
It should be understood that this method will not function properly for
inaccessible fields in the presence of a SecurityManager. Nor
will it function properly for non-existent fields (if a field called
fieldName does not exist on the class). All Throwables
encountered by this method will be rethrown as
IllegalAccessException. For wrapped Throwables, the
original cause can be accessed via IllegalAccessException's
getCause() method.
obj - the object from which the represented field's value is to be
extractedfieldName - the name of the field to be checked
obj;
primitive values are wrapped in an appropriate object before
being returned
IllegalAccessExceptionObject.getClass(),
Class.getDeclaredField(java.lang.String),
AccessibleObject.isAccessible(),
AccessibleObject.setAccessible(boolean),
Field.get(java.lang.Object),
Throwable.getCause()public static void sleep(long millis)
Thread to sleep for the specified timeout. This
method calls Thread.sleep(long millis), catching any thrown
InterruptedException and printing a stack trace to the
System.err.
millis - the length of time to sleep in milliseconds.Thread.sleep(long)
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