Package de.iip_ecosphere.platform.support.json

Class JsonUtils

java.lang.Object

de.iip_ecosphere.platform.support.json.JsonUtils

public class JsonUtils
extends Object

Some JSON utility methods, also reading/writing of specific types.

Author:

Holger Eichelberger, SSE, Lemur Project (BSD License)

Constructor Summary

Constructors

Constructor	Description
JsonUtils()

Method Summary

Modifier and Type	Method	Description
static String	escape(String input)	Escapes an input string for JSON.
static <R> R	fromJson(Object json, Class<R> cls)	Reads an Object from a JSON string.
static <R> List<R>	listFromJson(Object json, Class<R> cls)	Reads a typed List from a JSON string.
static <K, V> Map<K,V>	mapFromJson(Object json, Class<K> keyCls, Class<K> valueCls)	Reads a typed Map from a JSON string.
static String	toJson(Object obj)	Turns an object to JSON.
static String	unescape(String input)	Unescapes an input string from JSON.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Details

JsonUtils

public JsonUtils()

Method Details

toJson

public static String toJson(Object obj)

Turns an object to JSON.

Parameters:

obj - the object (may be null), must have getters/setters for all attributes and a no-arg constructor no-arg constructor

Returns:

the JSON string or an empty string in case of problems/no address

See Also:

• fromJson(Object, Class)

fromJson

public static <R> R fromJson(Object json,
 Class<R> cls)

Reads an Object from a JSON string.

Type Parameters:

R - the object type, must have getters/setters for all attributes and a no-arg constructor

Parameters:

json - the JSON value (usually a String)

cls - the class of the type to read

Returns:

the server address or null if reading fails

See Also:

• toJson(Object)

listFromJson

public static <R> List<R> listFromJson(Object json,
 Class<R> cls)

Reads a typed List from a JSON string.

Type Parameters:

R - the entity type

Parameters:

json - the JSON value (usually a String)

cls - the class of the entity type to read

Returns:

the list or null if reading fails

See Also:

• toJson(Object)

mapFromJson

public static <K,
V> Map<K,V> mapFromJson(Object json,
 Class<K> keyCls,
 Class<K> valueCls)

Reads a typed Map from a JSON string.

Type Parameters:

K - the key type

V - the value type

Parameters:

json - the JSON value (usually a String)

keyCls - the class of the key type to read

valueCls - the class of the value type to read

Returns:

the map or null if reading fails

See Also:

• toJson(Object)

escape

public static String escape(String input)

Escapes an input string for JSON. Taken over from Stackoverflow and Lemur Project. The respective methods from Apache Commons Lang3 are too slow for our purpose.

Parameters:

input - the input string

Returns:

the escaped string

unescape

public static String unescape(String input)

Unescapes an input string from JSON. Taken over from Stackoverflow and Lemur Project. The respective methods from Apache Commons Lang3 are too slow for our purpose.

Parameters:

input - the input string

Returns:

the unescaped string