Package com.google.gwt.core.client

Class JsonUtils

  • public class JsonUtils
extends java.lang.Object
    Provides JSON-related utility methods.

    • Method Summary

      All Methods Static Methods Concrete Methods 
      Modifier and Type Method Description
      static java.lang.String escapeJsonForEval​(java.lang.String toEscape)
      Escapes characters within a JSON string than cannot be passed directly to eval().
      static java.lang.String escapeValue​(java.lang.String toEscape)
      Returns a quoted, escaped JSON String.
      static <T extends JavaScriptObject>
      T      		 safeEval​(java.lang.String json)
      Evaluates a JSON expression safely.
      static boolean safeToEval​(java.lang.String text)
      Returns true if the given JSON string may be safely evaluated by eval() without undesired side effects or security risks.
      static java.lang.String stringify​(JavaScriptObject obj)
      Converts a value to JSON.
      static java.lang.String stringify​(JavaScriptObject obj, java.lang.String space)
      Converts a value to JSON.
      (package private) static void throwIllegalArgumentException​(java.lang.String message, java.lang.String data)  
      static <T extends JavaScriptObject>
      T      		 unsafeEval​(java.lang.String json)
      Evaluates a JSON expression using eval().

      • Methods inherited from class java.lang.Object

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

    • Method Detail

      • stringify

        public static java.lang.String stringify​(JavaScriptObject obj)
        Converts a value to JSON.

      • stringify

        public static java.lang.String stringify​(JavaScriptObject obj,
                                         java.lang.String space)
        Converts a value to JSON.
        Parameters:
        space - controls the spacing in the final string. Successive levels in the stringification will each be indented by this string (or the first ten characters of it).

      • escapeJsonForEval

        public static java.lang.String escapeJsonForEval​(java.lang.String toEscape)
        Escapes characters within a JSON string than cannot be passed directly to eval(). Control characters, quotes and backslashes are not affected.

      • escapeValue

        public static java.lang.String escapeValue​(java.lang.String toEscape)
        Returns a quoted, escaped JSON String.

      • safeEval

        public static <T extends JavaScriptObject> T safeEval​(java.lang.String json)
        Evaluates a JSON expression safely. The payload must evaluate to an Object or an Array (not a primitive or a String).
        Type Parameters:
        T - The type of JavaScriptObject that should be returned
        Parameters:
        json - The source JSON text
        Returns:
        The evaluated object
        Throws:
        java.lang.IllegalArgumentException - if the input is not valid JSON

      • safeToEval

        public static boolean safeToEval​(java.lang.String text)
        Returns true if the given JSON string may be safely evaluated by eval() without undesired side effects or security risks. Note that a true result from this method does not guarantee that the input string is valid JSON. This method does not consider the contents of quoted strings; it may still be necessary to perform escaping prior to evaluation for correct results.

        The technique used is taken from RFC 4627.

        Note that this function may fail in sufficiently large text in some browsers (e.g. Chrome). It is always better to use safeEval(java.lang.String) instead which is safer, faster and also works with large texts but less lenient than this one for invalid JSON.

      • unsafeEval

        public static <T extends JavaScriptObject> T unsafeEval​(java.lang.String json)
        Evaluates a JSON expression using eval(). This method does not validate the JSON text and should only be used on JSON from trusted sources. The payload must evaluate to an Object or an Array (not a primitive or a String).
        Type Parameters:
        T - The type of JavaScriptObject that should be returned
        Parameters:
        json - The source JSON text
        Returns:
        The evaluated object

      • throwIllegalArgumentException

        static void throwIllegalArgumentException​(java.lang.String message,
                                          java.lang.String data)