org.cogroo.util

Class ToStringHelper

java.lang.Object

org.cogroo.util.ToStringHelper

public class ToStringHelper
extends Object

Support class for Objects#toStringHelper.

Since:

2.0

Author:

Jason Lee

Method Summary

Modifier and Type	Method and Description
ToStringHelper	add(String name, boolean value) Adds a name/value pair to the formatted output in name=value format.
ToStringHelper	add(String name, char value) Adds a name/value pair to the formatted output in name=value format.
ToStringHelper	add(String name, double value) Adds a name/value pair to the formatted output in name=value format.
ToStringHelper	add(String name, float value) Adds a name/value pair to the formatted output in name=value format.
ToStringHelper	add(String name, int value) Adds a name/value pair to the formatted output in name=value format.
ToStringHelper	add(String name, long value) Adds a name/value pair to the formatted output in name=value format.
ToStringHelper	add(String name, Object value) Adds a name/value pair to the formatted output in name=value format.
ToStringHelper	addValue(boolean value) Adds an unnamed value to the formatted output.
ToStringHelper	addValue(char value) Adds an unnamed value to the formatted output.
ToStringHelper	addValue(double value) Adds an unnamed value to the formatted output.
ToStringHelper	addValue(float value) Adds an unnamed value to the formatted output.
ToStringHelper	addValue(int value) Adds an unnamed value to the formatted output.
ToStringHelper	addValue(long value) Adds an unnamed value to the formatted output.
ToStringHelper	addValue(Object value) Adds an unnamed value to the formatted output.
static <T> T	checkNotNull(T reference)
static <T> T	firstNonNull(T first, T second) Returns the first of two given parameters that is not null, if either is, or otherwise throws a NullPointerException.
String	toString() Returns a string in the format specified by Objects#toStringHelper(Object).
static ToStringHelper	toStringHelper(Class<?> clazz) Creates an instance of ToStringHelper in the same manner as Objects#toStringHelper(Object), but using the name of clazz instead of using an instance's Object.getClass().
static ToStringHelper	toStringHelper(Object self) Creates an instance of ToStringHelper.
static ToStringHelper	toStringHelper(String className) Creates an instance of ToStringHelper in the same manner as Objects#toStringHelper(Object), but using className instead of using an instance's Object.getClass().

Methods inherited from class java.lang.Object

equals, getClass, hashCode, notify, notifyAll, wait, wait, wait

Method Detail

add

public ToStringHelper add(String name,
                          Object value)

Adds a name/value pair to the formatted output in name=value format. If value is null, the string "null" is used, unless #omitNullValues() is called, in which case this name/value pair will not be added.

add

public ToStringHelper add(String name,
                          boolean value)

Adds a name/value pair to the formatted output in name=value format.

Since:

11.0 (source-compatible since 2.0)

add

public ToStringHelper add(String name,
                          char value)

Adds a name/value pair to the formatted output in name=value format.

Since:

11.0 (source-compatible since 2.0)

add

public ToStringHelper add(String name,
                          double value)

Adds a name/value pair to the formatted output in name=value format.

Since:

11.0 (source-compatible since 2.0)

add

public ToStringHelper add(String name,
                          float value)

Adds a name/value pair to the formatted output in name=value format.

Since:

11.0 (source-compatible since 2.0)

add

public ToStringHelper add(String name,
                          int value)

Adds a name/value pair to the formatted output in name=value format.

Since:

11.0 (source-compatible since 2.0)

add

public ToStringHelper add(String name,
                          long value)

Adds a name/value pair to the formatted output in name=value format.

Since:

11.0 (source-compatible since 2.0)

addValue

public ToStringHelper addValue(Object value)

Adds an unnamed value to the formatted output.

It is strongly encouraged to use add(String, Object) instead and give value a readable name.

addValue

public ToStringHelper addValue(boolean value)

Adds an unnamed value to the formatted output.

It is strongly encouraged to use add(String, boolean) instead and give value a readable name.

Since:

11.0 (source-compatible since 2.0)

addValue

public ToStringHelper addValue(char value)

Adds an unnamed value to the formatted output.

It is strongly encouraged to use add(String, char) instead and give value a readable name.

Since:

11.0 (source-compatible since 2.0)

addValue

public ToStringHelper addValue(double value)

Adds an unnamed value to the formatted output.

It is strongly encouraged to use add(String, double) instead and give value a readable name.

Since:

11.0 (source-compatible since 2.0)

addValue

public ToStringHelper addValue(float value)

Adds an unnamed value to the formatted output.

It is strongly encouraged to use add(String, float) instead and give value a readable name.

Since:

11.0 (source-compatible since 2.0)

addValue

public ToStringHelper addValue(int value)

Adds an unnamed value to the formatted output.

It is strongly encouraged to use add(String, int) instead and give value a readable name.

Since:

11.0 (source-compatible since 2.0)

addValue

public ToStringHelper addValue(long value)

Adds an unnamed value to the formatted output.

It is strongly encouraged to use add(String, long) instead and give value a readable name.

Since:

11.0 (source-compatible since 2.0)

toString

public String toString()

Returns a string in the format specified by Objects#toStringHelper(Object).

Overrides:

toString in class Object

toStringHelper

public static ToStringHelper toStringHelper(Object self)

Creates an instance of ToStringHelper.

This is helpful for implementing Object.toString(). Specification by example:

   
   // Returns "ClassName{}"
   Objects.toStringHelper(this)
       .toString();

   // Returns "ClassName{x=1}"
   Objects.toStringHelper(this)
       .add("x", 1)
       .toString();

   // Returns "MyObject{x=1}"
   Objects.toStringHelper("MyObject")
       .add("x", 1)
       .toString();

   // Returns "ClassName{x=1, y=foo}"
   Objects.toStringHelper(this)
       .add("x", 1)
       .add("y", "foo")
       .toString();
   }

   // Returns "ClassName{x=1}"
   Objects.toStringHelper(this)
       .omitNullValues()
       .add("x", 1)
       .add("y", null)
       .toString();
   }}

Note that in GWT, class names are often obfuscated.

Parameters:

self - the object to generate the string for (typically this), used only for its class name

Since:

2.0

toStringHelper

public static ToStringHelper toStringHelper(Class<?> clazz)

Creates an instance of ToStringHelper in the same manner as Objects#toStringHelper(Object), but using the name of clazz instead of using an instance's Object.getClass().

Note that in GWT, class names are often obfuscated.

Parameters:

clazz - the Class of the instance

Since:

7.0 (source-compatible since 2.0)

toStringHelper

public static ToStringHelper toStringHelper(String className)

Creates an instance of ToStringHelper in the same manner as Objects#toStringHelper(Object), but using className instead of using an instance's Object.getClass().

Parameters:

className - the name of the instance type

Since:

7.0 (source-compatible since 2.0)

firstNonNull

public static <T> T firstNonNull(T first,
                                 T second)

Returns the first of two given parameters that is not null, if either is, or otherwise throws a NullPointerException.

Note: if first is represented as an Optional<T>, this can be accomplished with first.or(second). That approach also allows for lazy evaluation of the fallback instance, using first.or(Supplier).

Returns:

first if first is not null, or second if first is null and second is not null

Throws:

NullPointerException - if both first and second were null

Since:

3.0

checkNotNull

public static <T> T checkNotNull(T reference)