org.apache.commons.lang.builder
Class ReflectionToStringBuilder
public class ReflectionToStringBuilder
Assists in implementing
Object.toString()
methods using reflection.
This class uses reflection to determine the fields to append. Because these fields are usually private, the class
uses
java.lang.reflect.AccessibleObject.setAccessible(java.lang.reflect.AccessibleObject[], boolean)
to
change the visibility of the fields. This will fail under a security manager, unless the appropriate permissions are
set up correctly.
A typical invocation for this method would look like:
public String toString() {
return ReflectionToStringBuilder.toString(this);
}
You can also use the builder to debug 3rd party objects:
System.out.println("An object: " + ReflectionToStringBuilder.toString(anObject));
A subclass can control field output by overriding the methods:
accept(java.lang.reflect.Field)
getValue(java.lang.reflect.Field)
For example, this method does
not include the
password
field in the returned
String
:
public String toString() {
return (new ReflectionToStringBuilder(this) {
protected boolean accept(Field f) {
return super.accept(f) && !f.getName().equals("password");
}
}).toString();
}
The exact format of the
toString
is determined by the
ToStringStyle
passed into the
constructor.
ReflectionToStringBuilder(Object object) -
Constructor.
|
ReflectionToStringBuilder(Object object, ToStringStyle style) -
Constructor.
|
ReflectionToStringBuilder(Object object, ToStringStyle style, StringBuffer buffer) -
Constructor.
|
ReflectionToStringBuilder(Object object, ToStringStyle style, StringBuffer buffer, Class reflectUpToClass, boolean outputTransients) - Use
ReflectionToStringBuilder(Object,ToStringStyle,StringBuffer,Class,boolean,boolean) .
|
ReflectionToStringBuilder(Object object, ToStringStyle style, StringBuffer buffer, Class reflectUpToClass, boolean outputTransients, boolean outputStatics) - Constructor.
|
protected boolean | accept(Field field) - Returns whether or not to append the given
Field .
|
protected void | appendFieldsIn(Class clazz) -
Appends the fields and values defined by the given object of the given Class.
|
String[] | getExcludeFieldNames()
|
Class | getUpToClass() -
Gets the last super class to stop appending fields for.
|
protected Object | getValue(Field field) -
Calls
java.lang.reflect.Field.get(Object) .
|
boolean | isAppendStatics() -
Gets whether or not to append static fields.
|
boolean | isAppendTransients() -
Gets whether or not to append transient fields.
|
ToStringBuilder | reflectionAppendArray(Object array) -
Append to the
toString an Object array.
|
void | setAppendStatics(boolean appendStatics) -
Sets whether or not to append static fields.
|
void | setAppendTransients(boolean appendTransients) -
Sets whether or not to append transient fields.
|
ReflectionToStringBuilder | setExcludeFieldNames(String[] excludeFieldNamesParam) - Sets the field names to exclude.
|
void | setUpToClass(Class clazz) -
Sets the last super class to stop appending fields for.
|
String | toString() -
Gets the String built by this builder.
|
static String | toString(Object object) -
Builds a
toString value using the default ToStringStyle through reflection.
|
static String | toString(Object object, ToStringStyle style) -
Builds a
toString value through reflection.
|
static String | toString(Object object, ToStringStyle style, boolean outputTransients) -
Builds a
toString value through reflection.
|
static String | toString(Object object, ToStringStyle style, boolean outputTransients, Class reflectUpToClass) - Use
toString(Object,ToStringStyle,boolean,boolean,Class)
|
static String | toString(Object object, ToStringStyle style, boolean outputTransients, boolean outputStatics) -
Builds a
toString value through reflection.
|
static String | toString(Object object, ToStringStyle style, boolean outputTransients, boolean outputStatics, Class reflectUpToClass) -
Builds a
toString value through reflection.
|
static String | toStringExclude(Object object, Collection excludeFieldNames) - Builds a String for a toString method excluding the given field names.
|
static String | toStringExclude(Object object, String excludeFieldName) - Builds a String for a toString method excluding the given field name.
|
static String | toStringExclude(Object object, String[] excludeFieldNames) - Builds a String for a toString method excluding the given field names.
|
append , append , append , append , append , append , append , append , append , append , append , append , append , append , append , append , append , append , append , append , append , append , append , append , append , append , append , append , append , append , append , append , append , append , append , append , append , append , append , append , append , append , append , append , append , append , appendAsObjectToString , appendSuper , appendToString , getDefaultStyle , getObject , getStringBuffer , getStyle , reflectionToString , reflectionToString , reflectionToString , reflectionToString , setDefaultStyle , toString |
ReflectionToStringBuilder
public ReflectionToStringBuilder(Object object)
Constructor.
This constructor outputs using the default style set with
setDefaultStyle
.
object
- the Object to build a toString
for, must not be null
ReflectionToStringBuilder
public ReflectionToStringBuilder(Object object,
ToStringStyle style)
Constructor.
If the style is
null
, the default style is used.
object
- the Object to build a toString
for, must not be null
style
- the style of the toString
to create, may be null
ReflectionToStringBuilder
public ReflectionToStringBuilder(Object object,
ToStringStyle style,
StringBuffer buffer)
Constructor.
If the style is
null
, the default style is used.
If the buffer is
null
, a new one is created.
object
- the Object to build a toString
forstyle
- the style of the toString
to create, may be null
buffer
- the StringBuffer
to populate, may be null
ReflectionToStringBuilder
public ReflectionToStringBuilder(Object object,
ToStringStyle style,
StringBuffer buffer,
Class reflectUpToClass,
boolean outputTransients)
Use ReflectionToStringBuilder(Object,ToStringStyle,StringBuffer,Class,boolean,boolean)
.
Constructor.
object
- the Object to build a toString
forstyle
- the style of the toString
to create, may be null
buffer
- the StringBuffer
to populate, may be null
reflectUpToClass
- the superclass to reflect up to (inclusive), may be null
outputTransients
- whether to include transient fields
ReflectionToStringBuilder
public ReflectionToStringBuilder(Object object,
ToStringStyle style,
StringBuffer buffer,
Class reflectUpToClass,
boolean outputTransients,
boolean outputStatics)
Constructor.
object
- the Object to build a toString
forstyle
- the style of the toString
to create, may be null
buffer
- the StringBuffer
to populate, may be null
reflectUpToClass
- the superclass to reflect up to (inclusive), may be null
outputTransients
- whether to include transient fieldsoutputStatics
- whether to include static fields
accept
protected boolean accept(Field field)
Returns whether or not to append the given
Field
.
field
- The Field to test.
- Whether or not to append the given
Field
.
appendFieldsIn
protected void appendFieldsIn(Class clazz)
Appends the fields and values defined by the given object of the given Class.
If a cycle is detected as an object is "toString()'ed", such an object is rendered as if
Object.toString()
had been called and not implemented by the object.
clazz
- The class of object parameter
getExcludeFieldNames
public String[] getExcludeFieldNames()
- Returns the excludeFieldNames.
getUpToClass
public Class getUpToClass()
Gets the last super class to stop appending fields for.
- The last super class to stop appending fields for.
getValue
protected Object getValue(Field field)
throws IllegalArgumentException,
IllegalAccessException
Calls java.lang.reflect.Field.get(Object)
.
field
- The Field to query.
- The Object from the given Field.
java.lang.reflect.Field.get(Object)
isAppendStatics
public boolean isAppendStatics()
Gets whether or not to append static fields.
- Whether or not to append static fields.
isAppendTransients
public boolean isAppendTransients()
Gets whether or not to append transient fields.
- Whether or not to append transient fields.
reflectionAppendArray
public ToStringBuilder reflectionAppendArray(Object array)
Append to the toString
an Object
array.
array
- the array to add to the toString
setAppendStatics
public void setAppendStatics(boolean appendStatics)
Sets whether or not to append static fields.
appendStatics
- Whether or not to append static fields.
setAppendTransients
public void setAppendTransients(boolean appendTransients)
Sets whether or not to append transient fields.
appendTransients
- Whether or not to append transient fields.
setExcludeFieldNames
public ReflectionToStringBuilder setExcludeFieldNames(String[] excludeFieldNamesParam)
Sets the field names to exclude.
excludeFieldNamesParam
- The excludeFieldNames to excluding from toString or null
.
setUpToClass
public void setUpToClass(Class clazz)
Sets the last super class to stop appending fields for.
clazz
- The last super class to stop appending fields for.
toString
public static String toString(Object object)
Builds a
toString
value using the default
ToStringStyle
through reflection.
It uses
AccessibleObject.setAccessible
to gain access to private fields. This means that it will
throw a security exception if run under a security manager, if the permissions are not set up correctly. It is
also not as efficient as testing explicitly.
Transient members will be not be included, as they are likely derived. Static fields will not be included.
Superclass fields will be appended.
object
- the Object to be output
toString
public static String toString(Object object,
ToStringStyle style)
Builds a
toString
value through reflection.
It uses
AccessibleObject.setAccessible
to gain access to private fields. This means that it will
throw a security exception if run under a security manager, if the permissions are not set up correctly. It is
also not as efficient as testing explicitly.
Transient members will be not be included, as they are likely derived. Static fields will not be included.
Superclass fields will be appended.
If the style is
null
, the default
ToStringStyle
is used.
object
- the Object to be outputstyle
- the style of the toString
to create, may be null
toString
public static String toString(Object object,
ToStringStyle style,
boolean outputTransients)
Builds a
toString
value through reflection.
It uses
AccessibleObject.setAccessible
to gain access to private fields. This means that it will
throw a security exception if run under a security manager, if the permissions are not set up correctly. It is
also not as efficient as testing explicitly.
If the
outputTransients
is
true
, transient members will be output, otherwise they
are ignored, as they are likely derived fields, and not part of the value of the Object.
Static fields will not be included. Superclass fields will be appended.
If the style is
null
, the default
ToStringStyle
is used.
object
- the Object to be outputstyle
- the style of the toString
to create, may be null
outputTransients
- whether to include transient fields
toString
public static String toString(Object object,
ToStringStyle style,
boolean outputTransients,
Class reflectUpToClass)
Use toString(Object,ToStringStyle,boolean,boolean,Class)
Builds a
toString
value through reflection.
It uses
AccessibleObject.setAccessible
to gain access to private fields. This means that it will
throw a security exception if run under a security manager, if the permissions are not set up correctly. It is
also not as efficient as testing explicitly.
If the
outputTransients
is
true
, transient members will be output, otherwise they
are ignored, as they are likely derived fields, and not part of the value of the Object.
Static fields will not be included. Superclass fields will be appended up to and including the specified
superclass. A null superclass is treated as
java.lang.Object
.
If the style is
null
, the default
ToStringStyle
is used.
object
- the Object to be outputstyle
- the style of the toString
to create, may be null
outputTransients
- whether to include transient fieldsreflectUpToClass
- the superclass to reflect up to (inclusive), may be null
toString
public static String toString(Object object,
ToStringStyle style,
boolean outputTransients,
boolean outputStatics)
Builds a
toString
value through reflection.
It uses
AccessibleObject.setAccessible
to gain access to private fields. This means that it will
throw a security exception if run under a security manager, if the permissions are not set up correctly. It is
also not as efficient as testing explicitly.
If the
outputTransients
is
true
, transient fields will be output, otherwise they
are ignored, as they are likely derived fields, and not part of the value of the Object.
If the
outputStatics
is
true
, static fields will be output, otherwise they are
ignored.
Static fields will not be included. Superclass fields will be appended.
If the style is
null
, the default
ToStringStyle
is used.
object
- the Object to be outputstyle
- the style of the toString
to create, may be null
outputTransients
- whether to include transient fieldsoutputStatics
- whether to include transient fields
toString
public static String toString(Object object,
ToStringStyle style,
boolean outputTransients,
boolean outputStatics,
Class reflectUpToClass)
Builds a
toString
value through reflection.
It uses
AccessibleObject.setAccessible
to gain access to private fields. This means that it will
throw a security exception if run under a security manager, if the permissions are not set up correctly. It is
also not as efficient as testing explicitly.
If the
outputTransients
is
true
, transient fields will be output, otherwise they
are ignored, as they are likely derived fields, and not part of the value of the Object.
If the
outputStatics
is
true
, static fields will be output, otherwise they are
ignored.
Superclass fields will be appended up to and including the specified superclass. A null superclass is treated as
java.lang.Object
.
If the style is
null
, the default
ToStringStyle
is used.
object
- the Object to be outputstyle
- the style of the toString
to create, may be null
outputTransients
- whether to include transient fieldsoutputStatics
- whether to include static fieldsreflectUpToClass
- the superclass to reflect up to (inclusive), may be null
toStringExclude
public static String toStringExclude(Object object,
Collection excludeFieldNames)
Builds a String for a toString method excluding the given field names.
object
- The object to "toString".excludeFieldNames
- The field names to exclude. Null excludes nothing.
toStringExclude
public static String toStringExclude(Object object,
String excludeFieldName)
Builds a String for a toString method excluding the given field name.
object
- The object to "toString".excludeFieldName
- The field name to exclude
toStringExclude
public static String toStringExclude(Object object,
String[] excludeFieldNames)
Builds a String for a toString method excluding the given field names.
object
- The object to "toString".excludeFieldNames
- The field names to exclude