package org.nutz.json.impl;
import java.io.IOException;
import java.io.Reader;
import java.util.LinkedHashMap;
import java.util.LinkedList;
import java.util.List;
import java.util.Map;
import org.nutz.json.JsonException;
import org.nutz.json.JsonParser;
import org.nutz.lang.Lang;
import org.nutz.lang.Streams;
import org.nutz.lang.stream.QueueReader;
import org.nutz.mapl.MaplCompile;
/**
* 将json理解为Map+List
*
* @author wendal
*
*/
public class JsonCompileImpl implements JsonParser, MaplCompile<Reader> {
private QueueReader qis;
public Object parse(Reader reader) {
if (reader == null)
return null;
this.qis = new QueueReader(reader);
try {
// 开始读取数据
qis.peek();
if (qis.isEnd()) {
return null;
}
skipCommentsAndBlank();
if (qis.peek() == 'v') {
/*
* Meet the var ioc ={ maybe, try to find the '{' and break
*/
OUTER: while (true) {
qis.poll();// 尝试找到{,以确定是否为"var ioc ={"格式
switch (qis.peek()) {
case '{':
// case '['://还真有人这样写
break OUTER;
}
}
}
return parseFromHere();
}
catch (IOException e) {
throw Lang.wrapThrow(e);
}
// 一定要关闭文件啊，有木有
finally {
Streams.safeClose(reader);
}
}
protected Object parseFromHere() throws IOException {
switch (qis.peek()) {
case '{':
Map<String, Object> map = new LinkedHashMap<String, Object>();
parseMap(map);
return map;
case '[':
List<Object> list = new LinkedList<Object>();
parseList(list);
return list;
case '"':
case '\'':
return parseString();// 看来是个String
default:
return parseSimpleType();// 其他基本数据类型
}
}
/**
*
* @param endTag
* 以什么作为结束符
*/
private String parseString() throws IOException {
int endTag = qis.poll();
// 直至读取到相应的结束符!
StringBuilder sb = new StringBuilder();
while (true) {
if (qis.peek() == endTag) {
qis.poll();
break;
}
if (qis.peek() == '\\') {// 转义字符?
parseSp(sb);
} else
sb.append((char) qis.poll());
}
return sb.toString();
}
// 读取转义字符
private void parseSp(StringBuilder sb) throws IOException {
qis.poll();
switch (qis.poll()) {
case 'n':
sb.append('\n');
break;
case 'r':
sb.append('\r');
break;
case 't':
sb.append('\t');
break;
case '\\':
sb.append('\\');
break;
case '\'':
sb.append('\'');
break;
case '\"':
sb.append('\"');
break;
case '/':
sb.append('/');
break;
case 'u':
char[] hex = new char[4];
for (int i = 0; i < 4; i++)
hex[i] = (char) qis.poll();
sb.append((char) Integer.valueOf(new String(hex), 16).intValue());
break;
case 'b': // 这个支持一下又何妨?
sb.append(' ');// 空格
break;
case 'f':
sb.append('\f');// 这个支持一下又何妨?
break;
default:
throw unexpectedChar(); // 1.b.37及之前的版本,会忽略非法的转义字符
}
}
/**
* 处理基本数据类型
*
* @return
*/
private Object parseSimpleType() throws IOException {
StringBuilder sb = new StringBuilder();
if (qis.startWith("true")) {
qis.skip(4);
return Boolean.TRUE;
}
if (qis.startWith("false")) {
qis.skip(5);
return Boolean.FALSE;
}
if (qis.startWith("undefined")) {
qis.skip(9);
return null;
}
if (qis.startWith("null")) {
qis.skip(4);
return null;
}
switch (qis.peek()) {
case '.':
case '0':
case '1':
case '2':
case '3':
case '4':
case '5':
case '6':
case '7':
case '8':
case '9':
case '-':
// 看来是数字
boolean hasPoint = qis.peek() == '.';
sb.append((char) qis.poll());
while (true) {
if (qis.isEnd()) {// 读完了? 处理一下
if (hasPoint)
return Double.parseDouble(sb.toString());
else {
Long p = Long.parseLong(sb.toString());
if (Integer.MIN_VALUE < p.longValue() && p.longValue() < Integer.MAX_VALUE)
return p.intValue();
return p;
}
}
switch (qis.peek()) {
case '0':
case '1':
case '2':
case '3':
case '4':
case '5':
case '6':
case '7':
case '8':
case '9':
sb.append((char) qis.poll());
break;
case '.':
if (hasPoint)
throw unexpectedChar();
else {
hasPoint = true;
sb.append((char) qis.poll());
break;
}
case 'L':
case 'l':
if (hasPoint)
throw unexpectedChar();
qis.poll();
return Long.parseLong(sb.toString());
case 'F':
case 'f':
qis.poll();
return Float.parseFloat(sb.toString());
default: {// 越界读取了!!
if (hasPoint)
return Double.parseDouble(sb.toString());
else {
Long p = Long.parseLong(sb.toString());
if (Integer.MIN_VALUE < p.longValue() && p.longValue() < Integer.MAX_VALUE)
return p.intValue();
return p;
}
}
}
}
default:
throw unexpectedChar();// 不是数值,不是布尔值,不是null和undefined? 玩野啊? 抛异常!!
}
}
/**
*
*/
private void parseMap(Map<String, Object> map) throws IOException {
qis.poll();
skipCommentsAndBlank();
if (qis.peek() == '}') {
qis.poll();
return;
}
while (true) {
parseMapItem(map);
skipCommentsAndBlank();
switch (qis.poll()) {
case '}':
return;
case ',':
skipCommentsAndBlank();
// 如果结束
if (qis.peek() == '}') {
qis.poll();
return;
}
continue;
default:
throw unexpectedChar();
}
}
}
/**
* 生成MAP对象
*
* @param map
* @throws IOException
*/
protected void parseMapItem(Map<String, Object> map) throws IOException {
map.put(fetchKey(), parseFromHere());
}
/**
* 找KEY
*/
protected String fetchKey() throws IOException {
// 找key
String key = null;
switch (qis.peek()) {
case '"':
case '\'':
key = parseString();
skipCommentsAndBlank();
// 去掉":"
if (!(qis.poll() == ':')) {
throw makeError("Error JSON (KEY : VALUE) syntax!");
}
break;
default:
// 没办法,看来是无分隔符的字符串,找一下吧
StringBuilder sb = new StringBuilder();
// sb.append((char) qis.peek());
OUTER: while (true) {
switch (qis.peek()) {
case '\\':// 特殊字符
qis.poll();
parseSp(sb);
break;
case ' ':
case '/':
qis.poll();
skipCommentsAndBlank();
if (qis.poll() == ':') {
key = sb.toString().trim().intern();
break OUTER;
} else
throw unexpectedChar();
case ':':
qis.poll();
key = sb.toString().trim().intern();
break OUTER;
default:
sb.append((char) qis.poll());
}
}
}
// TODO 判断一下key是否合法
// 当前字符为: 跳过去
skipCommentsAndBlank();
return key;
}
/**
* 处理List
*
* @param list
* @throws IOException
*/
private void parseList(List<Object> list) throws IOException {
qis.poll();
skipCommentsAndBlank();
if (qis.peek() == ']') {
qis.poll();
return;
}
while (true) {
list.add(parseFromHere());
skipCommentsAndBlank();
switch (qis.poll()) {
case ']':
return;
case ',':// 看来还有元素
skipCommentsAndBlank();
// 如果没有正确结束
if (qis.peek() == ']') {
qis.poll();
return;
}
continue;
default:
throw unexpectedChar();
}
}
}
private void skipCommentsAndBlank() throws IOException {
skipBlank();
while (qis.peek() == '/') {
int v = qis.peekNext();
if (v == '/') { // inline comment
qis.readLine();
} else if (v == '*') { // block comment
skipBlockComment();
} else {
throw makeError("Error comment syntax!");
}
skipBlank();
}
}
private void skipBlank() throws IOException {
while (qis.peek() >= 0 && qis.peek() <= 32)
qis.poll();
}
private void skipBlockComment() throws IOException {
// 过滤块注释开始的"/*"两个字符
qis.skip(2);
while (true) {
if (qis.poll() == '*') {
if (qis.peek() == '/') {
qis.poll();
break;
}
}
}
}
private JsonException makeError(String message) throws IOException {
return new JsonException(qis.getRow(), qis.getCol(), (char) qis.peek(), message);
}
private JsonException unexpectedChar() throws IOException {
return new JsonException(qis.getRow(), qis.getCol(), (char) qis.peek(), "Unexpected char");
}
// public static void main(String[] args) {
// StringReader sr = new
// StringReader("{abc :'ccc',ppp : 123 , xx : true }");
// StringCompile2 sc2 = new StringCompile2();
// System.out.println(sc2.parse(sr));
// System.out.println(new StringCompile2().parse(new
// StringReader("{abc:{abc:123f}}")));
// System.out.println(new StringCompile2().parse(new
// StringReader("{abc:{ abc:123f}}")));
// System.out.println(new StringCompile2().parse(new
// StringReader("{abc:{abc: 123f}}")));
// System.out.println(new StringCompile2().parse(new
// StringReader("[123,true]")));
// System.out.println(new StringCompile2().parse(new
// StringReader("[123,456]")));
// System.out.println(new StringCompile2().parse(new
// StringReader("[123,{abc:456}]")));
// System.out.println(new StringCompile2().parse(new
// StringReader("[123,456L]")));
// System.out.println(new StringCompile2().parse(new
// StringReader("123456789L")));
// System.out.println(new StringCompile2().parse(new StringReader("2.3")));
// System.out.println(new StringCompile2().parse(new StringReader("0.0f")));
// System.out.println(new StringCompile2().parse(new
// StringReader("2.9999")));
// System.out.println(new StringCompile2().parse(new StringReader("true")));
// System.out.println(new StringCompile2().parse(new
// StringReader("false")));
// System.out.println(new StringCompile2().parse(new StringReader("null")));
// System.out.println(new StringCompile2().parse(new
// StringReader("undefined")));
// System.out.println(new StringCompile2().parse(new
// StringReader("\"abc\"")));
// System.out.println(new StringCompile2().parse(new
// StringReader("\"a\'bc\"")));
// System.out.println(new StringCompile2().parse(new
// StringReader("\"\'a\\\"bc\"")));
//
// System.out.println(new StringCompile2().parse(new
// StringReader("var ioc = {id:6};")));
// }
}