Class JSONArray

java.lang.Object
com.github.openjson.JSONArray
All Implemented Interfaces:
Iterable<Object>
public class JSONArray extends Object implements Iterable<Object>
A dense indexed sequence of values. Values may be any mix of JSONObjects, other JSONArrays, Strings, Booleans, Integers, Longs, Doubles, null or JSONObject.NULL. Values may not be NaNs, infinities, or of any type not listed here. JSONArray has the same type coercion behavior and optional/mandatory accessors as JSONObject. See that class' documentation for details. Warning: this class represents null in two incompatible ways: the standard Java null reference, and the sentinel value JSONObject.NULL. In particular, get fails if the requested index holds the null reference, but succeeds if it holds JSONObject.NULL. Instances of this class are not thread safe. Although this class is non-final, it was not designed for inheritance and should not be subclassed. In particular, self-use by overridable methods is not specified. See Effective Java Item 17, "Design and Document or inheritance or else prohibit it" for further information.

  • Field Summary

    Fields
    Modifier and Type
    Field
    Description
    private final List<Object>
    values
     

  • Constructor Summary

    Constructors
    Constructor
    Description
    JSONArray()
    Creates a JSONArray with no values.
    JSONArray(JSONTokener readFrom)
    Creates a new JSONArray with values from the next array in the tokener.
    JSONArray(Object array)
    Creates a new JSONArray with values from the given primitive array.
    JSONArray(String json)
    Creates a new JSONArray with values from the JSON string.
    JSONArray(Collection<?> copyFrom)
    Creates a new JSONArray by copying all values from the given collection.

  • Method Summary

    Modifier and Type
    Method
    Description
    (package private) void
    checkedPut(Object value)
    Same as put(boolean), with added validity checks.
    protected void
    encode(JSONStringer stringer)
    Encodes this array using JSONStringer provided
    boolean
    equals(Object o)
     
    Object
    get(int index)
    Returns the value at index.
    boolean
    getBoolean(int index)
    Returns the value at index if it exists and is a boolean or can be coerced to a boolean.
    double
    getDouble(int index)
    Returns the value at index if it exists and is a double or can be coerced to a double.
    int
    getInt(int index)
    Returns the value at index if it exists and is an int or can be coerced to an int.
    JSONArray
    getJSONArray(int index)
    Returns the value at index if it exists and is a JSONArray.
    JSONObject
    getJSONObject(int index)
    Returns the value at index if it exists and is a JSONObject.
    long
    getLong(int index)
    Returns the value at index if it exists and is a long or can be coerced to a long.
    String
    getString(int index)
    Returns the value at index if it exists, coercing it if necessary.
    int
    hashCode()
     
    boolean
    isNull(int index)
    Returns true if this array has no value at index, or if its value is the null reference or JSONObject.NULL.
    Iterator<Object>
    iterator()
     
    String
    join(String separator)
    Returns a new string by alternating this array's values with separator.
    int
    length()
     
    Object
    opt(int index)
    Returns the value at index, or null if the array has no value at index.
    boolean
    optBoolean(int index)
    Returns the value at index if it exists and is a boolean or can be coerced to a boolean.
    boolean
    optBoolean(int index, boolean fallback)
    Returns the value at index if it exists and is a boolean or can be coerced to a boolean.
    double
    optDouble(int index)
    Returns the value at index if it exists and is a double or can be coerced to a double.
    double
    optDouble(int index, double fallback)
    Returns the value at index if it exists and is a double or can be coerced to a double.
    int
    optInt(int index)
    Returns the value at index if it exists and is an int or can be coerced to an int.
    int
    optInt(int index, int fallback)
    Returns the value at index if it exists and is an int or can be coerced to an int.
    JSONArray
    optJSONArray(int index)
    Returns the value at index if it exists and is a JSONArray.
    JSONObject
    optJSONObject(int index)
    Returns the value at index if it exists and is a JSONObject.
    long
    optLong(int index)
    Returns the value at index if it exists and is a long or can be coerced to a long.
    long
    optLong(int index, long fallback)
    Returns the value at index if it exists and is a long or can be coerced to a long.
    String
    optString(int index)
    Returns the value at index if it exists, coercing it if necessary.
    String
    optString(int index, String fallback)
    Returns the value at index if it exists, coercing it if necessary.
    JSONArray
    put(boolean value)
    Appends value to the end of this array.
    JSONArray
    put(double value)
    Appends value to the end of this array.
    JSONArray
    put(int value)
    Appends value to the end of this array.
    JSONArray
    put(int index, boolean value)
    Sets the value at index to value, null padding this array to the required length if necessary.
    JSONArray
    put(int index, double value)
    Sets the value at index to value, null padding this array to the required length if necessary.
    JSONArray
    put(int index, int value)
    Sets the value at index to value, null padding this array to the required length if necessary.
    JSONArray
    put(int index, long value)
    Sets the value at index to value, null padding this array to the required length if necessary.
    JSONArray
    put(int index, Object value)
    Sets the value at index to value, null padding this array to the required length if necessary.
    JSONArray
    put(int index, Collection<?> value)
    Sets the value at index to value wrapped into JSONArray, null padding this array to the required length if necessary.
    JSONArray
    put(long value)
    Appends value to the end of this array.
    JSONArray
    put(Object value)
    Appends value to the end of this array.
    JSONArray
    put(Collection<?> value)
    Appends value wrapped by JSONArray to the end of this array.
    Object
    remove(int index)
    Removes and returns the value at index, or null if the array has no value at index.
    JSONObject
    toJSONObject(JSONArray names)
    Returns a new object whose values are the values in this array, and whose names are the values in names.
    String
    toString()
    Encodes this array as a compact JSON string, such as:
    String
    toString(int indentSpaces)
    Encodes this array as a human readable JSON string for debugging, such as:
    String
    toString(JSONStringer stringer)
    Encodes this array using JSONStringer provided

    Methods inherited from class Object

    clone, finalize, getClass, notify, notifyAll, wait, wait, wait

    Methods inherited from interface Iterable

    forEach, spliterator

  • Field Details

  • Constructor Details

    • JSONArray

      public JSONArray()
      Creates a JSONArray with no values.

    • JSONArray

      public JSONArray(Collection<?> copyFrom)
      Creates a new JSONArray by copying all values from the given collection.
      Parameters:
      copyFrom - a collection whose values are of supported types. Unsupported values are not permitted and will yield an array in an inconsistent state.

    • JSONArray

      public JSONArray(JSONTokener readFrom) throws JSONException
      Creates a new JSONArray with values from the next array in the tokener.
      Parameters:
      readFrom - a tokener whose nextValue() method will yield a JSONArray.
      Throws:
      JSONException - if the parse fails or doesn't yield a JSONArray.

    • JSONArray

      public JSONArray(String json) throws JSONException
      Creates a new JSONArray with values from the JSON string.
      Parameters:
      json - a JSON-encoded string containing an array.
      Throws:
      JSONException - if the parse fails or doesn't yield a JSONArray.

    • JSONArray

      public JSONArray(Object array) throws JSONException
      Creates a new JSONArray with values from the given primitive array.
      Parameters:
      array - The values to use.
      Throws:
      JSONException - if any of the values are non-finite double values (i.e. NaN or infinite)

  • Method Details

    • length

      public int length()
      Returns:
      Returns the number of values in this array.

    • put

      public JSONArray put(boolean value)
      Appends value to the end of this array.
      Parameters:
      value - The value to append.
      Returns:
      this array.

    • put

      public JSONArray put(double value) throws JSONException
      Appends value to the end of this array.
      Parameters:
      value - a finite value. May not be NaNs or infinities.
      Returns:
      this array.
      Throws:
      JSONException - If the value is unacceptable.

    • put

      public JSONArray put(int value)
      Appends value to the end of this array.
      Parameters:
      value - The value to append.
      Returns:
      this array.

    • put

      public JSONArray put(long value)
      Appends value to the end of this array.
      Parameters:
      value - The value to append.
      Returns:
      this array.

    • put

      public JSONArray put(Collection<?> value)
      Appends value wrapped by JSONArray to the end of this array.
      Parameters:
      value - any collection.
      Returns:
      this array.

    • put

      public JSONArray put(Object value)
      Appends value to the end of this array.
      Parameters:
      value - a JSONObject, JSONArray, String, Boolean, Integer, Long, Double, JSONObject.NULL, or null. May not be NaNs or infinities. Unsupported values are not permitted and will cause the array to be in an inconsistent state.
      Returns:
      this array.

    • checkedPut

      void checkedPut(Object value) throws JSONException
      Same as put(boolean), with added validity checks.
      Parameters:
      value - The value to append.
      Throws:
      JSONException

    • put

      public JSONArray put(int index, boolean value) throws JSONException
      Sets the value at index to value, null padding this array to the required length if necessary. If a value already exists at index, it will be replaced.
      Parameters:
      index - Where to put the value.
      value - The value to set.
      Returns:
      this array.
      Throws:
      JSONException - This should never happen.

    • put

      public JSONArray put(int index, double value) throws JSONException
      Sets the value at index to value, null padding this array to the required length if necessary. If a value already exists at index, it will be replaced.
      Parameters:
      index - Where to put the value.
      value - a finite value. May not be NaNs or infinities.
      Returns:
      this array.
      Throws:
      JSONException - If the value is not a finite value.

    • put

      public JSONArray put(int index, int value) throws JSONException
      Sets the value at index to value, null padding this array to the required length if necessary. If a value already exists at index, it will be replaced.
      Parameters:
      index - Where to put the value.
      value - The value to set.
      Returns:
      this array.
      Throws:
      JSONException - Should never actually happen.

    • put

      public JSONArray put(int index, long value) throws JSONException
      Sets the value at index to value, null padding this array to the required length if necessary. If a value already exists at index, it will be replaced.
      Parameters:
      index - Where to put the value.
      value - The value to set.
      Returns:
      this array.
      Throws:
      JSONException - Should never actually happen.

    • put

      public JSONArray put(int index, Collection<?> value) throws JSONException
      Sets the value at index to value wrapped into JSONArray, null padding this array to the required length if necessary. If a value already exists at index, it will be replaced.
      Parameters:
      index - Where to put the value.
      value - The value to set.
      Returns:
      this array.
      Throws:
      JSONException - Should never actually happen.

    • put

      public JSONArray put(int index, Object value) throws JSONException
      Sets the value at index to value, null padding this array to the required length if necessary. If a value already exists at index, it will be replaced.
      Parameters:
      index - Where to put the value.
      value - a JSONObject, JSONArray, String, Boolean, Integer, Long, Double, JSONObject.NULL, or null. May not be NaNs or infinities.
      Returns:
      this array.
      Throws:
      JSONException - If the value cannot be represented as a finite double value.

    • isNull

      public boolean isNull(int index)
      Returns true if this array has no value at index, or if its value is the null reference or JSONObject.NULL.
      Parameters:
      index - Which value to check.
      Returns:
      true if the value is null.

    • get

      public Object get(int index) throws JSONException
      Returns the value at index.
      Parameters:
      index - Which value to get.
      Returns:
      the value at the specified location.
      Throws:
      JSONException - if this array has no value at index, or if that value is the null reference. This method returns normally if the value is JSONObject#NULL.

    • opt

      public Object opt(int index)
      Returns the value at index, or null if the array has no value at index.
      Parameters:
      index - Which value to get.
      Returns:
      the value at the specified location.

    • remove

      public Object remove(int index)
      Removes and returns the value at index, or null if the array has no value at index.
      Parameters:
      index - Which value to remove.
      Returns:
      The value previously at the specified location.

    • getBoolean

      public boolean getBoolean(int index) throws JSONException
      Returns the value at index if it exists and is a boolean or can be coerced to a boolean.
      Parameters:
      index - Which value to get.
      Returns:
      the value at the specified location.
      Throws:
      JSONException - if the value at index doesn't exist or cannot be coerced to a boolean.

    • optBoolean

      public boolean optBoolean(int index)
      Returns the value at index if it exists and is a boolean or can be coerced to a boolean. Returns false otherwise.
      Parameters:
      index - Which value to get.
      Returns:
      the value at the specified location.

    • optBoolean

      public boolean optBoolean(int index, boolean fallback)
      Returns the value at index if it exists and is a boolean or can be coerced to a boolean. Returns fallback otherwise.
      Parameters:
      index - Which value to get.
      fallback - the fallback value to return if no value exists.
      Returns:
      the value at the specified location or the fallback value.

    • getDouble

      public double getDouble(int index) throws JSONException
      Returns the value at index if it exists and is a double or can be coerced to a double.
      Parameters:
      index - Which value to get.
      Returns:
      the value at the specified location.
      Throws:
      JSONException - if the value at index doesn't exist or cannot be coerced to a double.

    • optDouble

      public double optDouble(int index)
      Returns the value at index if it exists and is a double or can be coerced to a double. Returns NaN otherwise.
      Parameters:
      index - Which value to get.
      Returns:
      the value at the specified location.

    • optDouble

      public double optDouble(int index, double fallback)
      Returns the value at index if it exists and is a double or can be coerced to a double. Returns fallback otherwise.
      Parameters:
      index - Which value to get.
      fallback - The fallback value to use if no value is at the specified location.
      Returns:
      the value at the specified location or the fallback value.

    • getInt

      public int getInt(int index) throws JSONException
      Returns the value at index if it exists and is an int or can be coerced to an int.
      Parameters:
      index - Which value to get.
      Returns:
      the value at the specified location.
      Throws:
      JSONException - if the value at index doesn't exist or cannot be coerced to a int.

    • optInt

      public int optInt(int index)
      Returns the value at index if it exists and is an int or can be coerced to an int. Returns 0 otherwise.
      Parameters:
      index - Which value to get.
      Returns:
      the value at the specified location.

    • optInt

      public int optInt(int index, int fallback)
      Returns the value at index if it exists and is an int or can be coerced to an int. Returns fallback otherwise.
      Parameters:
      index - Which value to get.
      fallback - The fallback value to use if no value is at the specified location.
      Returns:
      the value at the specified location or the fallback value.

    • getLong

      public long getLong(int index) throws JSONException
      Returns the value at index if it exists and is a long or can be coerced to a long.
      Parameters:
      index - Which value to get.
      Returns:
      the value at the specified location.
      Throws:
      JSONException - if the value at index doesn't exist or cannot be coerced to a long.

    • optLong

      public long optLong(int index)
      Returns the value at index if it exists and is a long or can be coerced to a long. Returns 0 otherwise.
      Parameters:
      index - Which value to get.
      Returns:
      the value at the specified location.

    • optLong

      public long optLong(int index, long fallback)
      Returns the value at index if it exists and is a long or can be coerced to a long. Returns fallback otherwise.
      Parameters:
      index - Which value to get.
      fallback - The fallback value to use if no value is at the specified location.
      Returns:
      the value at the specified location or the fallback value.

    • getString

      public String getString(int index) throws JSONException
      Returns the value at index if it exists, coercing it if necessary.
      Parameters:
      index - Which value to get.
      Returns:
      the value at the specified location.
      Throws:
      JSONException - if no such value exists.

    • optString

      public String optString(int index)
      Returns the value at index if it exists, coercing it if necessary. Returns the empty string if no such value exists.
      Parameters:
      index - Which value to get.
      Returns:
      the value at the specified location.

    • optString

      public String optString(int index, String fallback)
      Returns the value at index if it exists, coercing it if necessary. Returns fallback if no such value exists.
      Parameters:
      index - Which value to get.
      fallback - The fallback value to use if no value is at the specified location.
      Returns:
      the value at the specified location or the fallback value.

    • getJSONArray

      public JSONArray getJSONArray(int index) throws JSONException
      Returns the value at index if it exists and is a JSONArray.
      Parameters:
      index - Which value to get.
      Returns:
      the value at the specified location.
      Throws:
      JSONException - if the value doesn't exist or is not a JSONArray.

    • optJSONArray

      public JSONArray optJSONArray(int index)
      Returns the value at index if it exists and is a JSONArray. Returns null otherwise.
      Parameters:
      index - Which value to get.
      Returns:
      the value at the specified location.

    • getJSONObject

      public JSONObject getJSONObject(int index) throws JSONException
      Returns the value at index if it exists and is a JSONObject.
      Parameters:
      index - Which value to get.
      Returns:
      the value at the specified location.
      Throws:
      JSONException - if the value doesn't exist or is not a JSONObject.

    • optJSONObject

      public JSONObject optJSONObject(int index)
      Returns the value at index if it exists and is a JSONObject. Returns null otherwise.
      Parameters:
      index - Which value to get.
      Returns:
      the value at the specified location.

    • toJSONObject

      public JSONObject toJSONObject(JSONArray names) throws JSONException
      Returns a new object whose values are the values in this array, and whose names are the values in names. Names and values are paired up by index from 0 through to the shorter array's length. Names that are not strings will be coerced to strings. This method returns null if either array is empty.
      Parameters:
      names - The names to apply to the returned values.
      Returns:
      the newly constructed object.
      Throws:
      JSONException - Should not be possible.

    • join

      public String join(String separator) throws JSONException
      Returns a new string by alternating this array's values with separator. This array's string values are quoted and have their special characters escaped. For example, the array containing the strings '12" pizza', 'taco' and 'soda' joined on '+' returns this: 
      "12\" pizza"+"taco"+"soda"
      Parameters:
      separator - The string used to separate the returned values.
      Returns:
      the conjoined values.
      Throws:
      JSONException - Only if there is a coding error.

    • toString

      public String toString()
      Encodes this array as a compact JSON string, such as: 
      [94043,90210]
      Note 1: this method will not output any fields with 'null' value. Override JSONStringer.entry(Map.Entry) method to have nulls printed. Note 2: this method will suppress any internal exceptions. Use toString(JSONStringer) method directly to handle exceptions manually.
      Overrides:
      toString in class Object
      Returns:
      The string form of this array.

    • toString

      public String toString(int indentSpaces) throws JSONException
      Encodes this array as a human readable JSON string for debugging, such as: 
      [
    94043,
    90210
]
      Parameters:
      indentSpaces - the number of spaces to indent for each level of nesting.
      Returns:
      The string form of this array.
      Throws:
      JSONException - Only if there is a coding error.

    • toString

      public String toString(JSONStringer stringer) throws JSONException
      Encodes this array using JSONStringer provided
      Parameters:
      stringer - - JSONStringer to be used for serialization
      Returns:
      The string representation of this.
      Throws:
      JSONException - On internal errors. Shouldn't happen.

    • encode

      protected void encode(JSONStringer stringer)
      Encodes this array using JSONStringer provided
      Parameters:
      stringer - - JSONStringer to be used for serialization
      Throws:
      JSONException - On internal errors. Shouldn't happen.

    • iterator

      public Iterator<Object> iterator()
      Specified by:
      iterator in interface Iterable<Object>

    • equals

      public boolean equals(Object o)
      Overrides:
      equals in class Object

    • hashCode

      public int hashCode()
      Overrides:
      hashCode in class Object