Class JsonPathUtils

java.lang.Object
de.xima.fc.utils.JsonPathUtils
public class JsonPathUtils extends Object
Helper class for JSON paths. Follows RFC 9335 - JSONPath: Query Expressions for JSON
Since:
8.0.0
Author:
XIMA Media GmbH

  • Method Details

    • anyPathSegment

      public static String anyPathSegment()
      Returns the any-path-segment, i.e., "*", as per RFC 9535 - Selectors.
      Returns:
      The any-path-segment.

    • encodeForJsonPathDoubleQuotedStringLiteral

      public static String encodeForJsonPathDoubleQuotedStringLiteral(String name)
      Encodes a string for a JSON path string literal with double quotes, as per RFC 9535 - name selector. Assumes the string will be enclosed in double quotes. 
      name-selector       = string-literal

string-literal      = %x22 *double-quoted %x22 /     ; "string"
                      %x27 *single-quoted %x27       ; 'string'

double-quoted       = unescaped /
                      %x27      /                    ; '
                      ESC %x22  /                    ; \"
                      ESC escapable

single-quoted       = unescaped /
                      %x22      /                    ; "
                      ESC %x27  /                    ; \'
                      ESC escapable

ESC                 = %x5C                           ; \ backslash

unescaped           = %x20-21 /                      ; see RFC 8259
                         ; omit 0x22 "
                      %x23-26 /
                         ; omit 0x27 '
                      %x28-5B /
                         ; omit 0x5C \
                      %x5D-D7FF /
                         ; skip surrogate code points
                      %xE000-10FFFF

escapable           = %x62 / ; b BS backspace U+0008
                      %x66 / ; f FF form feed U+000C
                      %x6E / ; n LF line feed U+000A
                      %x72 / ; r CR carriage return U+000D
                      %x74 / ; t HT horizontal tab U+0009
                      "/"  / ; / slash (solidus) U+002F
                      "\"  / ; \ backslash (reverse solidus) U+005C
                      (%x75 hexchar) ;  uXXXX U+XXXX

hexchar             = non-surrogate /
                      (high-surrogate "\" %x75 low-surrogate)
non-surrogate       = ((DIGIT / "A"/"B"/"C" / "E"/"F") 3HEXDIG) /
                      ("D" %x30-37 2HEXDIG )
high-surrogate      = "D" ("8"/"9"/"A"/"B") 2HEXDIG
low-surrogate       = "D" ("C"/"D"/"E"/"F") 2HEXDIG

HEXDIG              = DIGIT / "A" / "B" / "C" / "D" / "E" / "F"
      Notes:
      • Double-quoted strings follow the JSON string syntax (Section 7 of [RFC8259]); single-quoted strings follow an analogous pattern. No attempt was made to improve on this syntax, so if it is desired to escape characters with scalar values above 0xFFFF, such as U+1F041 ("🁁", DOMINO TILE HORIZONTAL-02-02), they need to be represented by a pair of surrogate escapes ("🁁" in this case).
      • Alphabetic characters in quoted strings are case-insensitive in ABNF, so each of the hexadecimal digits within \u escapes (as specified in rules referenced by hexchar) can be either lowercase or uppercase, while the u in \u needs to be lowercase (indicated as %x75).
      Parameters:
      name - The JSON path name to encode.
      Returns:
      The encoded JSON path name.

    • encodeForJsonPathSingleQuotedStringLiteral

      public static String encodeForJsonPathSingleQuotedStringLiteral(String name)
      Encodes a string for a JSON path string literal with single quotes, as per RFC 9535 - name selector. Assumes the string will be enclosed in single quotes. 
      name-selector       = string-literal

string-literal      = %x22 *double-quoted %x22 /     ; "string"
                      %x27 *single-quoted %x27       ; 'string'

double-quoted       = unescaped /
                      %x27      /                    ; '
                      ESC %x22  /                    ; \"
                      ESC escapable

single-quoted       = unescaped /
                      %x22      /                    ; "
                      ESC %x27  /                    ; \'
                      ESC escapable

ESC                 = %x5C                           ; \ backslash

unescaped           = %x20-21 /                      ; see RFC 8259
                         ; omit 0x22 "
                      %x23-26 /
                         ; omit 0x27 '
                      %x28-5B /
                         ; omit 0x5C \
                      %x5D-D7FF /
                         ; skip surrogate code points
                      %xE000-10FFFF

escapable           = %x62 / ; b BS backspace U+0008
                      %x66 / ; f FF form feed U+000C
                      %x6E / ; n LF line feed U+000A
                      %x72 / ; r CR carriage return U+000D
                      %x74 / ; t HT horizontal tab U+0009
                      "/"  / ; / slash (solidus) U+002F
                      "\"  / ; \ backslash (reverse solidus) U+005C
                      (%x75 hexchar) ;  uXXXX U+XXXX

hexchar             = non-surrogate /
                      (high-surrogate "\" %x75 low-surrogate)
non-surrogate       = ((DIGIT / "A"/"B"/"C" / "E"/"F") 3HEXDIG) /
                      ("D" %x30-37 2HEXDIG )
high-surrogate      = "D" ("8"/"9"/"A"/"B") 2HEXDIG
low-surrogate       = "D" ("C"/"D"/"E"/"F") 2HEXDIG

HEXDIG              = DIGIT / "A" / "B" / "C" / "D" / "E" / "F"
      Notes:
      • Double-quoted strings follow the JSON string syntax (Section 7 of [RFC8259]); single-quoted strings follow an analogous pattern. No attempt was made to improve on this syntax, so if it is desired to escape characters with scalar values above 0xFFFF, such as U+1F041 ("🁁", DOMINO TILE HORIZONTAL-02-02), they need to be represented by a pair of surrogate escapes ("🁁" in this case).
      • Alphabetic characters in quoted strings are case-insensitive in ABNF, so each of the hexadecimal digits within \u escapes (as specified in rules referenced by hexchar) can be either lowercase or uppercase, while the u in \u needs to be lowercase (indicated as %x75).
      Parameters:
      name - The JSON path name to encode.
      Returns:
      The encoded JSON path name.

    • isJsonPathShorthandMemberName

      public static boolean isJsonPathShorthandMemberName(String name)
      Checks whether the given JSON member name is a shorthand member name as per RFC 9535 - syntax. 
      member-name-shorthand = name-first *name-char
name-first          = ALPHA /
                      "_"   /
                      %x80-D7FF /
                         ; skip surrogate code points
                      %xE000-10FFFF
name-char           = name-first / DIGIT
DIGIT               = %x30-39              ; 0-9
ALPHA               = %x41-5A / %x61-7A    ; A-Z / a-z
      Parameters:
      name - The JSON path name to check.
      Returns:
      true if the given JSON member name needs is a shorthand member name, false otherwise.

    • isRootPath

      public static boolean isRootPath(String jsonPath)
      Checks whether the given JSON path is the root path, i.e., "$".
      Parameters:
      jsonPath - The JSON path to check.
      Returns:
      true if the given JSON path is the root path, false otherwise.

    • joinPathSegment

      public static String joinPathSegment(Object[] segments, int start, int end)

    • joinPathSegment

      public static String joinPathSegment(Object[] segments, int start, int end, JsonPathUtils.QuoteStyle quoteStyle)

    • jsonPathIndexSegment

      public static String jsonPathIndexSegment(int index)
      Constructs a JSON path index segment for a given array index, as per RFC 9535 - name syntax. For example, given the index 2, this method returns [2].
      Parameters:
      index - An array index.
      Returns:
      The index segment for the given array index.
      Throws:
      IllegalArgumentException - If the given index is negative.

    • jsonPathNameSegment

      public static String jsonPathNameSegment(String name)
      Constructs a JSON path name segment for a given object property name, as per RFC 9535 - name syntax, using the default quote style (single quotes). For example, given the name foo, this method returns .foo, and for the name foo bar, it returns ['foo bar'].
      Parameters:
      name - A property name.
      Returns:
      The name segment for the given property name.

    • jsonPathNameSegment

      public static String jsonPathNameSegment(String name, JsonPathUtils.QuoteStyle quoteStyle)
      Constructs a JSON path name segment for a given object property name, as per RFC 9535 - name syntax, using the given quote style. For example, given the name foo, this method returns .foo, and for the name foo bar, it returns ["foo bar"].
      Parameters:
      name - A property name.
      quoteStyle - The quoting style for the JSON path string literal.
      Returns:
      The name segment for the given property name.

    • jsonPathSegment

      public static String jsonPathSegment(Object segment)
      Returns either jsonPathIndexSegment(int) or jsonPathNameSegment(String) depending on the type of the given segment, using the default quote style (single quotes). For a number, the index segment is returned, and for any other object, the name segment is returned.
      Parameters:
      segment - The segment, either a Number (for array indices) or any other object (for property names).
      Returns:
      The JSON path segment for the given segment.

    • jsonPathSegment

      public static String jsonPathSegment(Object segment, JsonPathUtils.QuoteStyle quoteStyle)
      Returns either jsonPathIndexSegment(int) or jsonPathNameSegment(String) depending on the type of the given segment, using the given quote style. For a number, the index segment is returned, and for any other object, the name segment is returned.
      Parameters:
      segment - The segment, either a Number (for array indices) or any other object (for property names).
      quoteStyle - The quoting style for the JSON path string literal.
      Returns:
      The JSON path segment for the given segment.

    • jsonSubPath

      public static String jsonSubPath(String path, Object key)
      Constructs a JSON path for a sub-element at the given name or index of the given path, using the default quote style (single quotes). The given key must be either a String (for object property names) or an Integer (for array indices).
      Parameters:
      path - The parent JSON path.
      key - The name or index of the sub-element.
      Returns:
      The JSON path for the sub-element.

    • jsonSubPath

      public static String jsonSubPath(String path, Object key, JsonPathUtils.QuoteStyle quoteStyle)
      Constructs a JSON path for a sub-element at the given name or index of the given path, using the given quote style. The given key must be either a String (for object property names) or an Integer (for array indices).
      Parameters:
      path - The parent JSON path.
      key - The name or index of the sub-element.
      quoteStyle - The quoting style for the JSON path string literal.
      Returns:
      The JSON path for the sub-element.

    • jsonSubPathAtIndex

      public static String jsonSubPathAtIndex(String parentPath, int index)
      Constructs a JSON path for a sub-element at the given array index of the given parent path.
      Parameters:
      parentPath - The parent JSON path.
      index - The index of the sub-element.
      Returns:
      The JSON path for the sub-element.
      Throws:
      IllegalArgumentException - If the given index is negative.

    • jsonSubPathAtName

      public static String jsonSubPathAtName(String parentPath, String name)
      Constructs a JSON path for a sub-element at the given object property name of the given parent path, using the default quote style (single quotes).
      Parameters:
      parentPath - The parent JSON path.
      name - The property name of the sub-element.
      Returns:
      The JSON path for the sub-element.

    • jsonSubPathAtName

      public static String jsonSubPathAtName(String parentPath, String name, JsonPathUtils.QuoteStyle quoteStyle)
      Constructs a JSON path for a sub-element at the given object property name of the given parent path, using the given quote style.
      Parameters:
      parentPath - The parent JSON path.
      name - The property name of the sub-element.
      quoteStyle - The quoting style for the JSON path string literal.
      Returns:
      The JSON path for the sub-element.

    • readValueAtJsonPath

      public static Object readValueAtJsonPath(Map<String,Object> json, Object pathValue)
      Returns the value of the object defined by the given JSON path if it exists.
      Parameters:
      json - to get the value from.
      pathValue - JSON path defining the location of the value within the given JSON object.
      Returns:
      The value of the object defined by the given JSON path if it exists and null otherwise.

    • rootPathSegment

      public static String rootPathSegment()
      Returns the root path segment, i.e., "$".
      Returns:
      The root path segment.