📄 jsonobject.java
字号:
* Get the int value associated with a key. If the number value is too
* large for an int, it will be clipped.
*
* @param key A key string.
* @return The integer value.
* @throws JSONException if the key is not found or if the value cannot
* be converted to an integer.
*/
public int getInt(String key) throws JSONException {
Object o = get(key);
return o instanceof Number ?
((Number)o).intValue() : (int)getDouble(key);
}
/**
* Get the JSONArray value associated with a key.
*
* @param key A key string.
* @return A JSONArray which is the value.
* @throws JSONException if the key is not found or
* if the value is not a JSONArray.
*/
public JSONArray getJSONArray(String key) throws JSONException {
Object o = get(key);
if (o instanceof JSONArray) {
return (JSONArray)o;
}
throw new JSONException("JSONObject[" + quote(key) +
"] is not a JSONArray.");
}
/**
* Get the JSONObject value associated with a key.
*
* @param key A key string.
* @return A JSONObject which is the value.
* @throws JSONException if the key is not found or
* if the value is not a JSONObject.
*/
public JSONObject getJSONObject(String key) throws JSONException {
Object o = get(key);
if (o instanceof JSONObject) {
return (JSONObject)o;
}
throw new JSONException("JSONObject[" + quote(key) +
"] is not a JSONObject.");
}
/**
* Get the long value associated with a key. If the number value is too
* long for a long, it will be clipped.
*
* @param key A key string.
* @return The long value.
* @throws JSONException if the key is not found or if the value cannot
* be converted to a long.
*/
public long getLong(String key) throws JSONException {
Object o = get(key);
return o instanceof Number ?
((Number)o).longValue() : (long)getDouble(key);
}
/**
* Get the string associated with a key.
*
* @param key A key string.
* @return A string which is the value.
* @throws JSONException if the key is not found.
*/
public String getString(String key) throws JSONException {
return get(key).toString();
}
/**
* Determine if the JSONObject contains a specific key.
* @param key A key string.
* @return true if the key exists in the JSONObject.
*/
public boolean has(String key) {
return this.myHashMap.containsKey(key);
}
/**
* Determine if the value associated with the key is null or if there is
* no value.
* @param key A key string.
* @return true if there is no value associated with the key or if
* the value is the JSONObject.NULL object.
*/
public boolean isNull(String key) {
return JSONObject.NULL.equals(opt(key));
}
/**
* Get an enumeration of the keys of the JSONObject.
*
* @return An iterator of the keys.
*/
public Iterator keys() {
return this.myHashMap.keySet().iterator();
}
/**
* Get the number of keys stored in the JSONObject.
*
* @return The number of keys in the JSONObject.
*/
public int length() {
return this.myHashMap.size();
}
/**
* Produce a JSONArray containing the names of the elements of this
* JSONObject.
* @return A JSONArray containing the key strings, or null if the JSONObject
* is empty.
*/
public JSONArray names() {
JSONArray ja = new JSONArray();
Iterator keys = keys();
while (keys.hasNext()) {
ja.put(keys.next());
}
return ja.length() == 0 ? null : ja;
}
/**
* Produce a string from a Number.
* @param n A Number
* @return A String.
* @throws JSONException If n is a non-finite number.
*/
static public String numberToString(Number n)
throws JSONException {
if (n == null) {
throw new JSONException("Null pointer");
}
testValidity(n);
// Shave off trailing zeros and decimal point, if possible.
String s = n.toString();
if (s.indexOf('.') > 0 && s.indexOf('e') < 0 && s.indexOf('E') < 0) {
while (s.endsWith("0")) {
s = s.substring(0, s.length() - 1);
}
if (s.endsWith(".")) {
s = s.substring(0, s.length() - 1);
}
}
return s;
}
/**
* Get an optional value associated with a key.
* @param key A key string.
* @return An object which is the value, or null if there is no value.
*/
public Object opt(String key) {
return key == null ? null : this.myHashMap.get(key);
}
/**
* Get an optional boolean associated with a key.
* It returns false if there is no such key, or if the value is not
* Boolean.TRUE or the String "true".
*
* @param key A key string.
* @return The truth.
*/
public boolean optBoolean(String key) {
return optBoolean(key, false);
}
/**
* Get an optional boolean associated with a key.
* It returns the defaultValue if there is no such key, or if it is not
* a Boolean or the String "true" or "false" (case insensitive).
*
* @param key A key string.
* @param defaultValue The default.
* @return The truth.
*/
public boolean optBoolean(String key, boolean defaultValue) {
try {
return getBoolean(key);
} catch (Exception e) {
return defaultValue;
}
}
/**
* Put a key/value pair in the JSONObject, where the value will be a
* JSONArray which is produced from a Collection.
* @param key A key string.
* @param value A Collection value.
* @return this.
* @throws JSONException
*/
public JSONObject put(String key, Collection value) throws JSONException {
put(key, new JSONArray(value));
return this;
}
/**
* Get an optional double associated with a key,
* or NaN if there is no such key or if its value is not a number.
* If the value is a string, an attempt will be made to evaluate it as
* a number.
*
* @param key A string which is the key.
* @return An object which is the value.
*/
public double optDouble(String key) {
return optDouble(key, Double.NaN);
}
/**
* Get an optional double associated with a key, or the
* defaultValue if there is no such key or if its value is not a number.
* If the value is a string, an attempt will be made to evaluate it as
* a number.
*
* @param key A key string.
* @param defaultValue The default.
* @return An object which is the value.
*/
public double optDouble(String key, double defaultValue) {
try {
Object o = opt(key);
return o instanceof Number ? ((Number)o).doubleValue() :
new Double((String)o).doubleValue();
} catch (Exception e) {
return defaultValue;
}
}
/**
* Get an optional int value associated with a key,
* or zero if there is no such key or if the value is not a number.
* If the value is a string, an attempt will be made to evaluate it as
* a number.
*
* @param key A key string.
* @return An object which is the value.
*/
public int optInt(String key) {
return optInt(key, 0);
}
/**
* Get an optional int value associated with a key,
* or the default if there is no such key or if the value is not a number.
* If the value is a string, an attempt will be made to evaluate it as
* a number.
*
* @param key A key string.
* @param defaultValue The default.
* @return An object which is the value.
*/
public int optInt(String key, int defaultValue) {
try {
return getInt(key);
} catch (Exception e) {
return defaultValue;
}
}
/**
* Get an optional JSONArray associated with a key.
* It returns null if there is no such key, or if its value is not a
* JSONArray.
*
* @param key A key string.
* @return A JSONArray which is the value.
*/
public JSONArray optJSONArray(String key) {
Object o = opt(key);
return o instanceof JSONArray ? (JSONArray)o : null;
}
/**
* Get an optional JSONObject associated with a key.
* It returns null if there is no such key, or if its value is not a
* JSONObject.
*
* @param key A key string.
* @return A JSONObject which is the value.
*/
public JSONObject optJSONObject(String key) {
Object o = opt(key);
return o instanceof JSONObject ? (JSONObject)o : null;
}
/**
* Get an optional long value associated with a key,
* or zero if there is no such key or if the value is not a number.
* If the value is a string, an attempt will be made to evaluate it as
* a number.
*
* @param key A key string.
* @return An object which is the value.
*/
public long optLong(String key) {
return optLong(key, 0);
}
/**
* Get an optional long value associated with a key,
* or the default if there is no such key or if the value is not a number.
* If the value is a string, an attempt will be made to evaluate it as
* a number.
*
* @param key A key string.
* @param defaultValue The default.
* @return An object which is the value.
*/
public long optLong(String key, long defaultValue) {
try {
return getLong(key);
} catch (Exception e) {
return defaultValue;
}
}
/**
* Get an optional string associated with a key.
* It returns an empty string if there is no such key. If the value is not
* a string and is not null, then it is coverted to a string.
*
* @param key A key string.
* @return A string which is the value.
*/
public String optString(String key) {
return optString(key, "");
}
/**
* Get an optional string associated with a key.
* It returns the defaultValue if there is no such key.
*
* @param key A key string.
* @param defaultValue The default.
* @return A string which is the value.
*/
public String optString(String key, String defaultValue) {
Object o = opt(key);
return o != null ? o.toString() : defaultValue;
}
/**
* Put a key/boolean pair in the JSONObject.
*
* @param key A key string.
* @param value A boolean which is the value.
* @return this.
* @throws JSONException If the key is null.
*/
public JSONObject put(String key, boolean value) throws JSONException {
put(key, value ? Boolean.TRUE : Boolean.FALSE);
return this;
}
/**
* Put a key/double pair in the JSONObject.
*
* @param key A key string.
* @param value A double which is the value.
* @return this.
* @throws JSONException If the key is null or if the number is invalid.
*/
public JSONObject put(String key, double value) throws JSONException {
put(key, new Double(value));
return this;
}
/**
* Put a key/int pair in the JSONObject.
*
* @param key A key string.
* @param value An int which is the value.
* @return this.
* @throws JSONException If the key is null.
*/
public JSONObject put(String key, int value) throws JSONException {
put(key, new Integer(value));
return this;
}
/**
* Put a key/long pair in the JSONObject.
*
* @param key A key string.
⌨️ 快捷键说明
复制代码
Ctrl + C
搜索代码
Ctrl + F
全屏模式
F11
切换主题
Ctrl + Shift + D
显示快捷键
?
增大字号
Ctrl + =
减小字号
Ctrl + -