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Adapter json-lib com.hynnet:json-lib:jar to easyjson
/*
* Copyright 2019 the original author or authors.
*
* Licensed under the Apache, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at http://www.gnu.org/licenses/lgpl-3.0.html
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package net.sf.json.util;
import com.jn.langx.util.Numbers;
import net.sf.json.*;
import java.util.regex.Pattern;
/**
* A JSONTokener takes a source string and extracts characters and tokens from
* it. It is used by the JSONObject and JSONArray constructors to parse JSON
* source strings.
*
* @author JSON.org
* @version 4
*/
public class JSONTokener {
/**
* Get the hex value of a character (base16).
*
* @param c A character between '0' and '9' or between 'A' and 'F' or between
* 'a' and 'f'.
* @return An int between 0 and 15, or -1 if c was not a hex digit.
*/
public static int dehexchar(char c) {
if (c >= '0' && c <= '9') {
return c - '0';
}
if (c >= 'A' && c <= 'F') {
return c - ('A' - 10);
}
if (c >= 'a' && c <= 'f') {
return c - ('a' - 10);
}
return -1;
}
/**
* The index of the next character.
*/
private int myIndex;
/**
* The source string being tokenized.
*/
private String mySource;
/**
* Construct a JSONTokener from a string.
*
* @param s A source string.
*/
public JSONTokener(String s) {
this.myIndex = 0;
if (s != null) {
s = s.trim();
} else {
s = "";
}
if (s.length() > 0) {
char first = s.charAt(0);
char last = s.charAt(s.length() - 1);
if (first == '[' && last != ']') {
throw syntaxError("Found starting '[' but missing ']' at the end.");
}
if (first == '{' && last != '}') {
throw syntaxError("Found starting '{' but missing '}' at the end.");
}
}
this.mySource = s;
}
/**
* Back up one character. This provides a sort of lookahead capability, so
* that you can test for a digit or letter before attempting to parse the
* next number or identifier.
*/
public void back() {
if (this.myIndex > 0) {
this.myIndex -= 1;
}
}
public int length() {
if (this.mySource == null) {
return 0;
}
return this.mySource.length();
}
public boolean matches(String pattern) {
String str = this.mySource.substring(this.myIndex);
return Pattern.compile(pattern).matcher(str).matches();
}
/**
* Determine if the source string still contains characters that next() can
* consume.
*
* @return true if not yet at the end of the source.
*/
public boolean more() {
return this.myIndex < this.mySource.length();
}
/**
* Get the next character in the source string.
*
* @return The next character, or 0 if past the end of the source string.
*/
public char next() {
if (more()) {
char c = this.mySource.charAt(this.myIndex);
this.myIndex += 1;
return c;
}
return 0;
}
/**
* Consume the next character, and check that it matches a specified
* character.
*
* @param c The character to match.
* @return The character.
* @throws JSONException if the character does not match.
*/
public char next(char c) {
char n = next();
if (n != c) {
throw syntaxError("Expected '" + c + "' and instead saw '" + n + "'.");
}
return n;
}
/**
* Get the next n characters.
*
* @param n The number of characters to take.
* @return A string of n characters.
* @throws JSONException Substring bounds error if there are not n characters
* remaining in the source string.
*/
public String next(int n) {
int i = this.myIndex;
int j = i + n;
if (j >= this.mySource.length()) {
throw syntaxError("Substring bounds error");
}
this.myIndex += n;
return this.mySource.substring(i, j);
}
/**
* Get the next char in the string, skipping whitespace and comments
* (slashslash, slashstar, and hash).
*
* @return A character, or 0 if there are no more characters.
* @throws JSONException
*/
public char nextClean() {
for (; ; ) {
char c = next();
if (c == '/') {
switch (next()) {
case '/':
do {
c = next();
} while (c != '\n' && c != '\r' && c != 0);
break;
case '*':
for (; ; ) {
c = next();
if (c == 0) {
throw syntaxError("Unclosed comment.");
}
if (c == '*') {
if (next() == '/') {
break;
}
back();
}
}
break;
default:
back();
return '/';
}
} else if (c == '#') {
do {
c = next();
} while (c != '\n' && c != '\r' && c != 0);
} else if (c == 0 || c > ' ') {
return c;
}
}
}
/**
* Return the characters up to the next close quote character. Backslash
* processing is done. The formal JSON format does not allow strings in
* single quotes, but an implementation is allowed to accept them.
*
* @param quote The quoting character, either " (double
* quote) or ' (single quote).
* @return A String.
* @throws JSONException Unterminated string.
*/
public String nextString(char quote) {
char c;
StringBuffer sb = new StringBuffer();
for (; ; ) {
c = next();
switch (c) {
case 0:
case '\n':
case '\r':
throw syntaxError("Unterminated string");
case '\\':
c = next();
switch (c) {
case 'b':
sb.append('\b');
break;
case 't':
sb.append('\t');
break;
case 'n':
sb.append('\n');
break;
case 'f':
sb.append('\f');
break;
case 'r':
sb.append('\r');
break;
case 'u':
sb.append((char) Integer.parseInt(next(4), 16));
break;
case 'x':
sb.append((char) Integer.parseInt(next(2), 16));
break;
default:
sb.append(c);
}
break;
default:
if (c == quote) {
return sb.toString();
}
sb.append(c);
}
}
}
/**
* Get the text up but not including the specified character or the end of
* line, whichever comes first.
*
* @param d A delimiter character.
* @return A string.
*/
public String nextTo(char d) {
StringBuffer sb = new StringBuffer();
for (; ; ) {
char c = next();
if (c == d || c == 0 || c == '\n' || c == '\r') {
if (c != 0) {
back();
}
return sb.toString()
.trim();
}
sb.append(c);
}
}
/**
* Get the text up but not including one of the specified delimeter
* characters or the end of line, whichever comes first.
*
* @param delimiters A set of delimiter characters.
* @return A string, trimmed.
*/
public String nextTo(String delimiters) {
char c;
StringBuffer sb = new StringBuffer();
for (; ; ) {
c = next();
if (delimiters.indexOf(c) >= 0 || c == 0 || c == '\n' || c == '\r') {
if (c != 0) {
back();
}
return sb.toString()
.trim();
}
sb.append(c);
}
}
/**
* Get the next value. The value can be a Boolean, Double, Integer,
* JSONArray, JSONObject, Long, or String, or the JSONObject.NULL object.
*
* @return An object.
* @throws JSONException If syntax error.
*/
public Object nextValue() {
return nextValue(new JsonConfig());
}
/**
* Get the next value. The value can be a Boolean, Double, Integer,
* JSONArray, JSONObject, Long, or String, or the JSONObject.NULL object.
*
* @return An object.
* @throws JSONException If syntax error.
*/
public Object nextValue(JsonConfig jsonConfig) {
char c = nextClean();
String s;
switch (c) {
case '"':
case '\'':
return nextString(c);
case '{':
back();
return JSONObject.fromObject(this, jsonConfig);
case '[':
back();
return JSONArray.fromObject(this, jsonConfig);
default:
// empty
}
/*
* Handle unquoted text. This could be the values true, false, or null, or
* it can be a number. An implementation (such as this one) is allowed to
* also accept non-standard forms. Accumulate characters until we reach
* the end of the text or a formatting character.
*/
StringBuffer sb = new StringBuffer();
char b = c;
while (c >= ' ' && ",:]}/\\\"[{;=#".indexOf(c) < 0) {
sb.append(c);
c = next();
}
back();
/*
* If it is true, false, or null, return the proper value.
*/
s = sb.toString()
.trim();
if (s.equals("")) {
throw syntaxError("Missing value.");
}
if (s.equalsIgnoreCase("true")) {
return Boolean.TRUE;
}
if (s.equalsIgnoreCase("false")) {
return Boolean.FALSE;
}
if (s.equals("null") ||
(jsonConfig.isJavascriptCompliant() && s.equals("undefined"))) {
return JSONNull.getInstance();
}
/*
* If it might be a number, try converting it. We support the 0- and 0x-
* conventions. If a number cannot be produced, then the value will just
* be a string. Note that the 0-, 0x-, plus, and implied string
* conventions are non-standard. A JSON parser is free to accept non-JSON
* forms as long as it accepts all correct JSON forms.
*/
if ((b >= '0' && b <= '9') || b == '.' || b == '-' || b == '+') {
if (b == '0') {
if (s.length() > 2 && (s.charAt(1) == 'x' || s.charAt(1) == 'X')) {
try {
return new Integer(Integer.parseInt(s.substring(2), 16));
} catch (Exception e) {
/* Ignore the error */
}
} else {
try {
return new Integer(Integer.parseInt(s, 8));
} catch (Exception e) {
/* Ignore the error */
}
}
}
try {
return Numbers.createNumber(s);
} catch (Exception e) {
return s;
}
}
if (JSONUtils.isFunctionHeader(s) || JSONUtils.isFunction(s)) {
return s;
}
switch (peek()) {
case ',':
case '}':
case '{':
case '[':
case ']':
throw new JSONException("Unquotted string '" + s + "'");
}
return s;
}
/**
* Look at the next character in the source string.
*
* @return The next character, or 0 if past the end of the source string.
*/
public char peek() {
if (more()) {
char c = this.mySource.charAt(this.myIndex);
return c;
}
return 0;
}
public void reset() {
this.myIndex = 0;
}
/**
* Skip characters until past the requested string. If it is not found, we
* are left at the end of the source.
*
* @param to A string to skip past.
*/
public void skipPast(String to) {
this.myIndex = this.mySource.indexOf(to, this.myIndex);
if (this.myIndex < 0) {
this.myIndex = this.mySource.length();
} else {
this.myIndex += to.length();
}
}
/**
* Skip characters until the next character is the requested character. If
* the requested character is not found, no characters are skipped.
*
* @param to A character to skip to.
* @return The requested character, or zero if the requested character is not
* found.
*/
public char skipTo(char to) {
char c;
int index = this.myIndex;
do {
c = next();
if (c == 0) {
this.myIndex = index;
return c;
}
} while (c != to);
back();
return c;
}
/**
* Make a JSONException to signal a syntax error.
*
* @param message The error message.
* @return A JSONException object, suitable for throwing
*/
public JSONException syntaxError(String message) {
return new JSONException(message + toString());
}
/**
* Make a printable string of this JSONTokener.
*
* @return " at character [this.myIndex] of [this.mySource]"
*/
@Override
public String toString() {
return " at character " + this.myIndex + " of " + this.mySource;
}
}