jsonarray.java

《ajax基础教程》源码

     * @return      The truth.
     */
    public boolean optBoolean(int index, boolean defaultValue)  {
        Object o = opt(index);
        if (o != null) {
            if (o == Boolean.FALSE || 
					(o instanceof String && 
					((String)o).equalsIgnoreCase("false"))) {
                return false;
            } else if (o == Boolean.TRUE || 
					(o instanceof String && 
					((String)o).equalsIgnoreCase("true"))) {
                return true;
            }
        }
        return defaultValue;
    }


    /**
     * Get the optional double value associated with an index.
     * NaN is returned if the index is not found,
     * or if the value is not a number and cannot be converted to a number.
     *
     * @param index The index must be between 0 and length() - 1.
     * @return      The value.
     */
    public double optDouble(int index) {
        return optDouble(index, Double.NaN);
    }


    /**
     * Get the optional double value associated with an index.
     * The defaultValue is returned if the index is not found,
     * or if the value is not a number and cannot be converted to a number.
     *
     * @param index subscript
     * @param defaultValue     The default value.
     * @return      The value.
     */
    public double optDouble(int index, double defaultValue) {
        Object o = opt(index);
        if (o != null) {
            if (o instanceof Number) {
                return ((Number) o).doubleValue();
            }
            try {
                return new Double((String)o).doubleValue();
            }
            catch (Exception e) {
            }
        }
        return defaultValue;
    }


    /**
     * Get the optional int value associated with an index.
     * Zero is returned if the index is not found,
     * or if the value is not a number and cannot be converted to a number.
     *
     * @param index The index must be between 0 and length() - 1.
     * @return      The value.
     */
    public int optInt(int index) {
        return optInt(index, 0);
    }


    /**
     * Get the optional int value associated with an index.
     * The defaultValue is returned if the index is not found,
     * or if the value is not a number and cannot be converted to a number.
     * @param index The index must be between 0 and length() - 1.
     * @param defaultValue     The default value.
     * @return      The value.
     */
    public int optInt(int index, int defaultValue) {
        Object o = opt(index);
        if (o != null) {
            if (o instanceof Number) {
                return ((Number)o).intValue();
            }
            try {
                return Integer.parseInt((String)o);
            }
            catch (Exception e) {
            }
        }
        return defaultValue;
    }


    /**
     * Get the optional JSONArray associated with an index.
     * @param index subscript
     * @return      A JSONArray value, or null if the index has no value,
     * or if the value is not a JSONArray.
     */
    public JSONArray optJSONArray(int index) {
        Object o = opt(index);
        if (o instanceof JSONArray) {
            return (JSONArray)o;
        }
        return null;
    }


    /**
     * Get the optional JSONObject associated with an index.
     * Null is returned if the key is not found, or null if the index has
     * no value, or if the value is not a JSONObject.
     *
     * @param index The index must be between 0 and length() - 1.
     * @return      A JSONObject value.
     */
    public JSONObject optJSONObject(int index) {
        Object o = opt(index);
        if (o instanceof JSONObject) {
            return (JSONObject)o;
        }
        return null;
    }


    /**
     * Get the optional string value associated with an index. It returns an
     * empty string if there is no value at that index. If the value
     * is not a string and is not null, then it is coverted to a string.
     *
     * @param index The index must be between 0 and length() - 1.
     * @return      A String value.
     */
    public String optString(int index){
        return optString(index, "");
    }


    /**
     * Get the optional string associated with an index.
     * The defaultValue is returned if the key is not found.
     *
     * @param index The index must be between 0 and length() - 1.
     * @param defaultValue     The default value.
     * @return      A String value.
     */
    public String optString(int index, String defaultValue){
        Object o = opt(index);
        if (o != null) {
            return o.toString();
        }
        return defaultValue;
    }


    /**
     * Append a boolean value.
     *
     * @param value A boolean value.
     * @return this.
     */
    public JSONArray put(boolean value) {
        put(new Boolean(value));
        return this;
    }


    /**
     * Append a double value.
     *
     * @param value A double value.
     * @return this.
     */
    public JSONArray put(double value) {
        put(new Double(value));
        return this;
    }


    /**
     * Append an int value.
     *
     * @param value An int value.
     * @return this.
     */
    public JSONArray put(int value) {
        put(new Integer(value));
        return this;
    }


    /**
     * Append an object value.
     * @param value An object value.  The value should be a
     *  Boolean, Double, Integer, JSONArray, JSObject, or String, or the
     *  JSONObject.NULL object.
     * @return this.
     */
    public JSONArray put(Object value) {
        myArrayList.add(value);
        return this;
    }


    /**
     * Put or replace a boolean value in the JSONArray.
     * @exception NoSuchElementException The index must not be negative.
     * @param index subscript The subscript. If the index is greater than the length of
     *  the JSONArray, then null elements will be added as necessary to pad
     *  it out.
     * @param value A boolean value.
     * @return this.
     */
    public JSONArray put(int index, boolean value) {
        put(index, new Boolean(value));
        return this;
    }


    /**
     * Put or replace a double value.
     * @exception NoSuchElementException The index must not be negative.
     * @param index subscript The subscript. If the index is greater than the length of
     *  the JSONArray, then null elements will be added as necessary to pad
     *  it out.
     * @param value A double value.
     * return this.
     */
    public JSONArray put(int index, double value) {
        put(index, new Double(value));
        return this;
    }


    /**
     * Put or replace an int value.
     * @exception NoSuchElementException The index must not be negative.
     * @param index subscript The subscript. If the index is greater than the length of
     *  the JSONArray, then null elements will be added as necessary to pad
     *  it out.
     * @param value An int value.
     * @return this.
     */
    public JSONArray put(int index, int value) {
        put(index, new Integer(value));
        return this;
    }


    /**
     * Put or replace an object value in the JSONArray.
     * @exception NoSuchElementException The index must not be negative.
     * @param index The subscript. If the index is greater than the length of
     *  the JSONArray, then null elements will be added as necessary to pad
     *  it out.
     * @param value An object value.
     * return this.
     */
    public JSONArray put(int index, Object value)
            throws NoSuchElementException, NullPointerException {
        if (index < 0) {
            throw new NoSuchElementException("JSONArray[" + index +
                "] not found.");
        } else if (value == null) {
            throw new NullPointerException();
        } else if (index < length()) {
            myArrayList.set(index, value);
        } else {
            while (index != length()) {
                put(null);
            }
            put(value);
        }
        return this;
    }


    /**
     * Produce a JSONObject by combining a JSONArray of names with the values
     * of this JSONArray.
     * @param names A JSONArray containing a list of key strings. These will be
     * paired with the values.
     * @return A JSONObject, or null if there are no names or if this JSONArray
     * has no values.
     */
    public JSONObject toJSONObject(JSONArray names) {
        if (names == null || names.length() == 0 || length() == 0) {
            return null;
        }
        JSONObject jo = new JSONObject();
        for (int i = 0; i < names.length(); i += 1) {
            jo.put(names.getString(i), this.opt(i));
        }
        return jo;
    }


    /**
     * Make an JSON external form string of this JSONArray. For compactness, no
     * unnecessary whitespace is added.
     * Warning: This method assumes that the data structure is acyclical.
     *
     * @return a printable, displayable, transmittable
     *  representation of the array.
     */
    public String toString() {
        return '[' + join(",") + ']';
    }


    /**
     * Make a prettyprinted JSON string of this JSONArray.
     * Warning: This method assumes that the data structure is non-cyclical.
     * @param indentFactor The number of spaces to add to each level of
     *  indentation.
     * @return a printable, displayable, transmittable
     *  representation of the object, beginning 
     *  with <code>[</code>&nbsp;<small>(left bracket)</small> and ending 
     *  with <code>]</code>&nbsp;<small>(right bracket)</small>.
     */
    public String toString(int indentFactor) {
        return toString(indentFactor, 0);
    }


    /**
     * Make a prettyprinted string of this JSONArray.
     * Warning: This method assumes that the data structure is non-cyclical.
     * @param indentFactor The number of spaces to add to each level of
     *  indentation.
     * @param indent The indention of the top level.
     * @return a printable, displayable, transmittable
     *  representation of the array.
     */
    String toString(int indentFactor, int indent) {
        int i;
        Object o;
        String pad = "";
        StringBuffer sb = new StringBuffer();
        int newindent = indent + indentFactor;
		int len = myArrayList.size();
		if (len == 0) {
			return "[]";
		}
        for (i = 0; i < newindent; i += 1) {
            pad += ' ';
        }
        sb.append("[\n");
        for (i = 0; i < len; i += 1) {
            if (i > 0) {
                sb.append(",\n");
            }
            sb.append(pad);
            o = myArrayList.get(i);
            if (o == null) {
                sb.append("null");
            } else if (o instanceof String) {
                sb.append(JSONObject.quote((String) o));
            } else if (o instanceof Number) {
                sb.append(JSONObject.numberToString((Number) o));
            } else if (o instanceof JSONObject) {
                sb.append(((JSONObject)o).toString(indentFactor, newindent));
            } else if (o instanceof JSONArray) {
                sb.append(((JSONArray)o).toString(indentFactor, newindent));
            } else {
                sb.append(o.toString());
            }
        }
		sb.append('\n');
        for (i = 0; i < indent; i += 1) {
			sb.append(' ');
        }
        sb.append(']');
        return sb.toString();
    }
}