Package jsonvalues
Class JsPath
- java.lang.Object
-
- jsonvalues.JsPath
-
- All Implemented Interfaces:
Comparable<JsPath>
public final class JsPath extends Object implements Comparable<JsPath>
Represents the full path location of an element in a json. It's a list of
Position
. Exists two different ways to create a JsPath: - From a path-like string using the static factory methodpath(String)
, where the path follows the Json Pointer specification RFC 6901. In order to be able to use paths to put data in a Json, keys which name are numbers have to to be single-quoted:a={"0": true} b=[false]
According to the rfc 6901: the pointer /0 points to true in a, and to false in b. In json-values it's slightly different: /0 points to false in b, and /'0' points to true in a. It's necessary to make that distinction because otherwise, there are scenarios when there is no way to know if the user wants to insert an array or an object:JsObj obj = empty.put("/a/0/0",true) obj = {"a":[[true]]} //valid result according to the rfc and json-values obj = {"a":{"0":{"0":true} //valid result according to the rfc } - By an API, using the methods {@link #fromKey(String)} and {@link #fromIndex(int)} to create a JsPath an then the methods {@link #index(int)}} and {@link #key(String)} to append keys or indexes: {@code JsPath a = JsPath.fromKey("a").index(0).key("b") = /a/0/b JsPath b = JsPath.fromIndex(0).key("a").index(0) = /0/a/0 } For example, given the following Json object: { "a": { "x":[ {"c": [1,2, { "": { "1" : true, " ": false, "'": 4} }]} ]}} "1": null, "": ""
/ = "" //an empty string is a valid name for a key /'1' = null //numeric keys have to be single-quoted /a/x/0/c/0 = 1 /a/x/0/c/1 = 2 /a/x/0/c/2//'1' = true // single quotes are only mandatory when the key is a number according to the rfc, # at the beginning indicates that the path is a fragment of an url and therefore the keys have to be url-encoded: #/a/x/0/c/2//+" = false // + is url-decoded to the white-space #/a/x/0/c/2//%27" = 4 // %27 is url-decoded to ' and using the API:fromKey("") = "" fromKey("1") = null fromKey("a").key("x").index(0).key("c").index(0) = 1 fromKey("a").key("x").index(0).key("c").index(1) = 2 fromKey("a").key("x").index(0).key("c").index(2).key("").key("1") = true fromKey("a").key("x").index(0).key("c").index(2).key("").key(" ") = false fromKey("a").key("x").index(0).key("c").index(2).key("").key("'") = 4
-
-
Method Summary
All Methods Static Methods Instance Methods Concrete Methods Modifier and Type Method Description JsPath
append(JsPath path)
Creates a new JsPath appending the given path to this path.int
compareTo(JsPath that)
Compares this path with another given as a parameter by comparing in order each of their positions, one by one, until a result different than zero is returned or all the positions of any path are consumed.JsPath
dec()
Returns a new path decrementing the last index by one, throwing an UserError if the last Position is not an indexstatic JsPath
empty()
Returns the singleton empty path.boolean
endsWith(JsPath path)
returns true if this path ends with the given path.boolean
equals(@Nullable Object that)
Indicates whether some other object is "equal to" this pathstatic JsPath
fromIndex(int i)
returns a path from an indexstatic JsPath
fromKey(String key)
returns a path from a keyint
hashCode()
Returns the hashcode of this pathPosition
head()
Returns the head of this path if it's not empty, throwing an exception otherwise.<T> T
ifEmptyElse(Supplier<T> emptySupplier, Supplier<T> noneEmptySupplier)
Provides a declarative way of implementing an if-else statement based on the condition of if this path is empty or not.<T> T
ifPredicateElse(Predicate<? super JsPath> predicate, Supplier<T> ifTrueFn, Supplier<T> ifFalseFn)
Provides a declarative way of implementing an if-else statement based on the condition given by the predicate.JsPath
inc()
Returns a new path incrementing the last index by one, throwing an UserError if the last Position is not an indexJsPath
index(int i)
Returns a new path appending an index with the given value to the back of this path.JsPath
init()
Returns a new path without the last Position of this path.boolean
isEmpty()
Returns true if the path is empty.boolean
isNotEmpty()
JsPath
key(String key)
creates a new JsPath appending the key tothis
JsPath.Position
last()
returns the last positionthis
JsPath if it's not empty or a exception otherwise.JsPath
mapKeys(UnaryOperator<String> map)
Creates a new JsPath applying the given map function to every key of this path.static JsPath
path(String path)
JsPath
prepend(JsPath path)
Creates a new JsPath prepending the given path to this path.int
size()
boolean
startsWith(JsPath path)
returns true if this path starts with the given path.Stream<Position>
stream()
Returns a sequentialStream
of Positions with this path as its source.JsPath
tail()
String
toString()
Returns a string representation of this path following the format defined in the RFC 6901 with the exception that keys which names are numbers are single-quoted.String
toUriFragment()
Returns a string representation of this path following the format defined in the RFC 6901 for uri fragments, with the exception that keys which names are numbers are single-quoted Example: #/a/b/0/'1'/c+d where keys have been been url-encoded
-
-
-
Method Detail
-
empty
public static JsPath empty()
Returns the singleton empty path.- Returns:
- the singleton empty path
-
compareTo
public int compareTo(JsPath that)
Compares this path with another given as a parameter by comparing in order each of their positions, one by one, until a result different than zero is returned or all the positions of any path are consumed.- Specified by:
compareTo
in interfaceComparable<JsPath>
- Parameters:
that
- the given path- Returns:
- 1 if this is greater than that, -1 if this is lower than that, 0 otherwise
- See Also:
index.compareTo(position)
,key.compareTo(position)
-
head
public Position head()
Returns the head of this path if it's not empty, throwing an exception otherwise.- Returns:
- the head of the path witch is an object of type Position representing and Index or a Key
- Throws:
UserError
- if the path is empty
-
ifEmptyElse
public <T> T ifEmptyElse(Supplier<T> emptySupplier, Supplier<T> noneEmptySupplier)
Provides a declarative way of implementing an if-else statement based on the condition of if this path is empty or not. The value returned by each branch is computed by a supplier.- Type Parameters:
T
- the type of the result- Parameters:
emptySupplier
- the supplier that will compute the result only if the path is emptynoneEmptySupplier
- the supplier that will compute the result only if the path is not empty- Returns:
- an object of type T
-
stream
public Stream<Position> stream()
Returns a sequentialStream
of Positions with this path as its source.- Returns:
- stream of Positions of this path
-
ifPredicateElse
public <T> T ifPredicateElse(Predicate<? super JsPath> predicate, Supplier<T> ifTrueFn, Supplier<T> ifFalseFn)
Provides a declarative way of implementing an if-else statement based on the condition given by the predicate. The value returned by each branch is computed by a supplier.- Type Parameters:
T
- the type of the result- Parameters:
predicate
- the given predicateifTrueFn
- the supplier that will compute the result only if the path tested on the predicate is trueifFalseFn
- the supplier that will compute the result only if the path tested on the predicate is false- Returns:
- an object of type T
-
inc
public JsPath inc()
Returns a new path incrementing the last index by one, throwing an UserError if the last Position is not an index- Returns:
- a new JsPath with the last index incremented by one
- Throws:
UserError
- if the last position is not an Index
-
dec
public JsPath dec()
Returns a new path decrementing the last index by one, throwing an UserError if the last Position is not an index- Returns:
- a new JsPath with the last index decremented by one
- Throws:
UserError
- if the last position is not an Index
-
index
public JsPath index(int i)
Returns a new path appending an index with the given value to the back of this path.- Parameters:
i
- the value of the index to be appended- Returns:
- a new JsPath with the Index appended to the back
-
init
public JsPath init()
Returns a new path without the last Position of this path.- Returns:
- a new JsPath without the last Position of this JsPath
- Throws:
UserError
- if the JsPath is empty
-
isEmpty
public boolean isEmpty()
Returns true if the path is empty. An empty path represents the empty key- Returns:
- true if this path is empty, false otherwise
-
isNotEmpty
public boolean isNotEmpty()
- Returns:
- false if this path is not empty
-
key
public JsPath key(String key)
creates a new JsPath appending the key tothis
JsPath.- Parameters:
key
- the key name to be appended in raw, without encoding nor single-quoting like inpath(String)
)}- Returns:
- a JsPath with the key appended to the back
-
last
public Position last()
returns the last positionthis
JsPath if it's not empty or a exception otherwise.- Returns:
- the last position the JsPath witch is an object of type Position representing and Index or a Key
- Throws:
UserError
- if the JsPath is empty
-
size
public int size()
- Returns:
- the number of Position (keys and indexes) of
this
JsPath
-
fromKey
public static JsPath fromKey(String key)
returns a path from a key- Parameters:
key
- the name of the key- Returns:
- a new JsPath
-
fromIndex
public static JsPath fromIndex(int i)
returns a path from an index- Parameters:
i
- the index- Returns:
- a new JsPath
-
tail
public JsPath tail()
- Returns:
- a JsPath without the head of
this
JsPath - Throws:
UserError
- if the JsPath is empty
-
toString
public String toString()
Returns a string representation of this path following the format defined in the RFC 6901 with the exception that keys which names are numbers are single-quoted. Example: /a/b/0/'1'/
-
toUriFragment
public String toUriFragment()
Returns a string representation of this path following the format defined in the RFC 6901 for uri fragments, with the exception that keys which names are numbers are single-quoted Example: #/a/b/0/'1'/c+d where keys have been been url-encoded- Returns:
- a string representation of this JsPath following the RFC 6901
-
mapKeys
public JsPath mapKeys(UnaryOperator<String> map)
Creates a new JsPath applying the given map function to every key of this path.- Parameters:
map
- the given map function- Returns:
- a new JsPath with all its Keys mapped with the given function
-
append
public JsPath append(JsPath path)
Creates a new JsPath appending the given path to this path.- Parameters:
path
- the given JsPath to be appended- Returns:
- a new JsPath with the given JsPath appended to
this
JsPath
-
prepend
public JsPath prepend(JsPath path)
Creates a new JsPath prepending the given path to this path.- Parameters:
path
- the given path to be prepended- Returns:
- a new JsPath with the given JsPath prepended to
this
JsPath
-
equals
public boolean equals(@Nullable Object that)
Indicates whether some other object is "equal to" this path
-
startsWith
public boolean startsWith(JsPath path)
returns true if this path starts with the given path. If the given path is JsPath.empty(), it always returns true- Parameters:
path
- the given path- Returns:
- true if this JsPath starts with the given JsPath
-
endsWith
public boolean endsWith(JsPath path)
returns true if this path ends with the given path. If the given path is JsPath.empty(), it always returns true- Parameters:
path
- the given path- Returns:
- true if this JsPath ends with the given JsPath
-
-