org.redkale.convert.json.JsonReader Maven / Gradle / Ivy
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* and open the template in the editor.
*/
package org.redkale.convert.json;
import org.redkale.convert.*;
import static org.redkale.convert.Reader.*;
import org.redkale.util.*;
/**
* JSON数据源
*
*
* 详情见: https://redkale.org
*
* @author zhangjx
*/
public class JsonReader extends Reader {
protected int position = -1;
private char[] text;
private int limit;
public static ObjectPool createPool(int max) {
return new ObjectPool<>(max, (Object... params) -> new JsonReader(), null, JsonReader::recycle);
}
public JsonReader() {
}
public JsonReader(String json) {
setText(Utility.charArray(json));
}
public JsonReader(char[] text) {
setText(text, 0, text.length);
}
public JsonReader(char[] text, int start, int len) {
setText(text, start, len);
}
public final void setText(String text) {
setText(Utility.charArray(text));
}
public final void setText(char[] text) {
setText(text, 0, text.length);
}
public final void setText(char[] text, int start, int len) {
this.text = text;
this.position = start - 1;
this.limit = start + len - 1;
}
protected boolean recycle() {
this.position = -1;
this.limit = -1;
this.text = null;
return true;
}
public void close() {
this.recycle();
}
/**
* 找到指定的属性值 例如: {id : 1, data : { name : 'a', items : [1,2,3]}} seek('data.items') 直接跳转到 [1,2,3];
*
* @param key 指定的属性名
*/
public final void seek(String key) {
if (key == null || key.length() < 1) return;
final String[] keys = key.split("\\.");
nextGoodChar(); //读掉 { [
for (String key1 : keys) {
while (this.hasNext()) {
String field = this.readSmallString();
readBlank();
if (key1.equals(field)) break;
skipValue();
}
}
}
/**
* 跳过属性的值
*/
@Override
public final void skipValue() {
final char ch = nextGoodChar();
switch (ch) {
case '"':
case '\'':
backChar(ch);
readString();
break;
case '{':
while (hasNext()) {
this.readSmallString(); //读掉field
this.readBlank();
this.skipValue();
}
break;
case '[':
while (hasNext()) {
this.skipValue();
}
break;
default:
char c;
for (;;) {
c = nextChar();
if (c <= ' ') return;
if (c == '}' || c == ']' || c == ',' || c == ':') {
backChar(c);
return;
}
}
}
}
/**
* 读取下一个字符， 不跳过空白字符
*
* @return 空白字符或有效字符
*/
protected char nextChar() {
return this.text[++this.position];
}
/**
* 跳过空白字符， 返回一个非空白字符
*
* @return 有效字符
*/
protected char nextGoodChar() {
char c = nextChar();
if (c > ' ') return c;
for (;;) {
c = nextChar();
if (c > ' ') return c;
}
}
/**
* 回退最后读取的字符
*
* @param ch 后退的字符
*/
protected void backChar(char ch) {
this.position--;
}
/**
* 判断下一个非空白字符是否为{
*
* @param clazz 类名
*
* @return 返回 null 表示对象为null， 返回空字符串表示当前class与返回的class一致，返回非空字符串表示class是当前class的子类。
*/
@Override
public String readObjectB(final Class clazz) {
this.fieldIndex = 0; //必须要重置为0
char ch = this.text[++this.position];
if (ch == '{') return "";
if (ch <= ' ') {
for (;;) {
ch = this.text[++this.position];
if (ch > ' ') break;
}
if (ch == '{') return "";
}
if (ch == 'n' && text[++position] == 'u' && text[++position] == 'l' && text[++position] == 'l') return null;
if (ch == 'N' && text[++position] == 'U' && text[++position] == 'L' && text[++position] == 'L') return null;
throw new ConvertException("a json object text must begin with '{' (position = " + position + ") but '" + ch + "' in (" + new String(this.text) + ")");
}
@Override
public final void readObjectE(final Class clazz) {
}
/**
* 判断下一个非空白字符是否为{
*
* @param member DeMember
* @param keydecoder Decodeable
*
* @return SIGN_NOLENGTH 或 SIGN_NULL
*/
@Override
public final int readMapB(DeMember member, Decodeable keydecoder) {
return readArrayB(member, keydecoder);
}
@Override
public final void readMapE() {
}
/**
* 判断下一个非空白字符是否为[
*
* @param member DeMember
* @param decoder Decodeable
*
* @return SIGN_NOLENGTH 或 SIGN_NULL
*/
@Override
public int readArrayB(DeMember member, Decodeable decoder) {
char ch = this.text[++this.position];
if (ch == '[') return SIGN_NOLENGTH;
if (ch == '{') return SIGN_NOLENGTH;
if (ch <= ' ') {
for (;;) {
ch = this.text[++this.position];
if (ch > ' ') break;
}
if (ch == '[') return SIGN_NOLENGTH;
if (ch == '{') return SIGN_NOLENGTH;
}
if (ch == 'n' && text[++position] == 'u' && text[++position] == 'l' && text[++position] == 'l') return SIGN_NULL;
if (ch == 'N' && text[++position] == 'U' && text[++position] == 'L' && text[++position] == 'L') return SIGN_NULL;
throw new ConvertException("a json array text must begin with '[' (position = " + position + ") but '" + ch + "' in (" + new String(this.text) + ")");
}
@Override
public final void readArrayE() {
}
/**
* 判断下一个非空白字符是否:
*/
@Override
public void readBlank() {
char ch = this.text[++this.position];
if (ch == ':') return;
if (ch <= ' ') {
for (;;) {
ch = this.text[++this.position];
if (ch > ' ') break;
}
if (ch == ':') return;
}
throw new ConvertException("'" + new String(text) + "'expected a ':' but '" + ch + "'(position = " + position + ") in (" + new String(this.text) + ")");
}
@Override
public int position() {
return this.position;
}
@Override
public int readMemberContentLength(DeMember member, Decodeable decoder) {
return -1;
}
/**
* 判断对象是否存在下一个属性或者数组是否存在下一个元素
*
* @param startPosition 起始位置
* @param contentLength 内容大小， 不确定的传-1
*
* @return 是否存在
*/
@Override
public boolean hasNext(int startPosition, int contentLength) {
char ch = this.text[++this.position];
if (ch == ',') return true;
if (ch == '}' || ch == ']') return false;
if (ch <= ' ') {
for (;;) {
ch = this.text[++this.position];
if (ch > ' ') break;
}
if (ch == ',') return true;
if (ch == '}' || ch == ']') return false;
}
this.position--; // { [ 交由 readObjectB 或 readMapB 或 readArrayB 读取
return true;
}
@Override
public final String readClassName() {
return null;
}
@Override
public String readSmallString() {
final int eof = this.limit;
if (this.position == eof) return null;
final char[] text0 = this.text;
int currpos = this.position;
char ch = text0[++currpos];
if (ch <= ' ') {
for (;;) {
ch = text0[++currpos];
if (ch > ' ') break;
}
}
if (ch == '"' || ch == '\'') {
final char quote = ch;
final int start = currpos + 1;
for (;;) {
ch = text0[++currpos];
if (ch == '\\') {
this.position = currpos - 1;
return readEscapeValue(quote, start);
} else if (ch == quote) {
break;
}
}
this.position = currpos;
char[] chs = new char[currpos - start];
System.arraycopy(text0, start, chs, 0, chs.length);
return new String(chs);
} else {
int start = currpos;
for (;;) {
if (currpos == eof) break;
ch = text0[++currpos];
if (ch == ',' || ch == ']' || ch == '}' || ch <= ' ' || ch == ':') break;
}
int len = currpos - start;
if (len < 1) {
this.position = currpos;
return String.valueOf(ch);
}
this.position = currpos - 1;
if (len == 4 && text0[start] == 'n' && text0[start + 1] == 'u' && text0[start + 2] == 'l' && text0[start + 3] == 'l') return null;
return new String(text0, start, len);
}
}
/**
* 读取一个int值
*
* @return int值
*/
@Override
public int readInt() {
final char[] text0 = this.text;
final int eof = this.limit;
int currpos = this.position;
char firstchar = text0[++currpos];
if (firstchar <= ' ') {
for (;;) {
firstchar = text0[++currpos];
if (firstchar > ' ') break;
}
}
boolean quote = false;
if (firstchar == '"' || firstchar == '\'') {
quote = true;
firstchar = text0[++currpos];
if (firstchar <= ' ') {
for (;;) {
firstchar = text0[++currpos];
if (firstchar > ' ') break;
}
}
if (firstchar == '"' || firstchar == '\'') {
this.position = currpos;
return 0;
}
}
int value = 0;
final boolean negative = firstchar == '-';
if (!negative) {
if (firstchar < '0' || firstchar > '9') throw new ConvertException("illegal escape(" + firstchar + ") (position = " + currpos + ") in (" + new String(this.text) + ")");
value = firstchar - '0';
}
for (;;) {
if (currpos == eof) break;
char ch = text0[++currpos];
int val = digits[ch];
if (quote && val == -3) continue;
if (val <= -3) break;
if (val == -1) throw new ConvertException("illegal escape(" + ch + ") (position = " + currpos + ") but '" + ch + "' in (" + new String(this.text) + ")");
if (val != -2) value = value * 10 + val;
}
this.position = currpos - 1;
return negative ? -value : value;
}
/**
* 读取一个long值
*
* @return long值
*/
@Override
public long readLong() {
final char[] text0 = this.text;
final int eof = this.limit;
int currpos = this.position;
char firstchar = text0[++currpos];
if (firstchar <= ' ') {
for (;;) {
firstchar = text0[++currpos];
if (firstchar > ' ') break;
}
}
boolean quote = false;
if (firstchar == '"' || firstchar == '\'') {
quote = true;
firstchar = text0[++currpos];
if (firstchar <= ' ') {
for (;;) {
firstchar = text0[++currpos];
if (firstchar > ' ') break;
}
}
if (firstchar == '"' || firstchar == '\'') {
this.position = currpos;
return 0L;
}
}
long value = 0;
final boolean negative = firstchar == '-';
if (!negative) {
if (firstchar < '0' || firstchar > '9') throw new ConvertException("illegal escape(" + firstchar + ") (position = " + currpos + ") in (" + new String(this.text) + ")");
value = firstchar - '0';
}
for (;;) {
if (currpos == eof) break;
char ch = text0[++currpos];
int val = digits[ch];
if (quote && val == -3) continue;
if (val <= -3) break;
if (val == -1) throw new ConvertException("illegal escape(" + ch + ") (position = " + currpos + ") but '" + ch + "' in (" + new String(this.text) + ")");
if (val != -2) value = value * 10 + val;
}
this.position = currpos - 1;
return negative ? -value : value;
}
@Override
public final DeMember readFieldName(final DeMember[] members) {
final String exceptedfield = this.readSmallString();
if (exceptedfield == null) return null;
final int len = members.length;
if (this.fieldIndex >= len) this.fieldIndex = 0;
for (int k = this.fieldIndex; k < len; k++) {
if (exceptedfield.equals(members[k].getAttribute().field())) {
this.fieldIndex = k;
return members[k];
}
}
for (int k = 0; k < this.fieldIndex; k++) {
if (exceptedfield.equals(members[k].getAttribute().field())) {
this.fieldIndex = k;
return members[k];
}
}
return null;
//if (result == null && len == 1 && text0[start] == '@') return REFER;
}
//------------------------------------------------------------
@Override
public final boolean readBoolean() {
return "true".equalsIgnoreCase(this.readSmallString());
}
@Override
public final byte readByte() {
return (byte) readInt();
}
@Override
public final byte[] readByteArray() {
int len = readArrayB(null, null);
int contentLength = -1;
if (len == Reader.SIGN_NULL) return null;
if (len == Reader.SIGN_NOLENBUTBYTES) {
contentLength = readMemberContentLength(null, null);
len = Reader.SIGN_NOLENGTH;
}
if (len == Reader.SIGN_NOLENGTH) {
int size = 0;
byte[] data = new byte[8];
int startPosition = position();
while (hasNext(startPosition, contentLength)) {
if (size >= data.length) {
byte[] newdata = new byte[data.length + 4];
System.arraycopy(data, 0, newdata, 0, size);
data = newdata;
}
data[size++] = readByte();
}
readArrayE();
byte[] newdata = new byte[size];
System.arraycopy(data, 0, newdata, 0, size);
return newdata;
} else {
byte[] values = new byte[len];
for (int i = 0; i < values.length; i++) {
values[i] = readByte();
}
readArrayE();
return values;
}
}
@Override
public final char readChar() {
return (char) readInt();
}
@Override
public final short readShort() {
return (short) readInt();
}
@Override
public final float readFloat() {
String chars = readSmallString();
if (chars != null) chars = chars.trim();
if (chars == null || chars.isEmpty()) return 0.f;
return Float.parseFloat(chars);
}
@Override
public final double readDouble() {
String chars = readSmallString();
if (chars != null) chars = chars.trim();
if (chars == null || chars.isEmpty()) return 0.0;
return Double.parseDouble(chars);
}
/**
* 读取字符串， 必须是"或者'包围的字符串值
*
* @return String值
*/
@Override
public String readString() {
final char[] text0 = this.text;
int currpos = this.position;
char expected = text0[++currpos];
if (expected <= ' ') {
for (;;) {
expected = text0[++currpos];
if (expected > ' ') break;
}
}
if (expected != '"' && expected != '\'') {
if (expected == 'n' && text0.length > currpos + 3 && (text0[1 + currpos] == 'u' && text0[2 + currpos] == 'l' && text0[3 + currpos] == 'l')) {
if (text0[++currpos] == 'u' && text0[++currpos] == 'l' && text0[++currpos] == 'l') {
this.position = currpos;
if (text0.length > currpos + 4) {
char ch = text0[currpos + 1];
if (ch == ',' || ch <= ' ' || ch == '}' || ch == ']' || ch == ':') return null;
final int start = currpos - 3;
for (;;) {
if (currpos >= text0.length) break;
ch = text0[currpos];
if (ch == ',' || ch <= ' ' || ch == '}' || ch == ']' || ch == ':') break;
currpos++;
}
if (currpos == start) throw new ConvertException("expected a string after a key but '" + text0[position] + "' (position = " + position + ") in (" + new String(this.text) + ")");
this.position = currpos - 1;
return new String(text0, start, currpos - start);
} else {
return null;
}
}
} else {
final int start = currpos;
for (;;) {
if (currpos >= text0.length) break;
char ch = text0[currpos];
if (ch == ',' || ch <= ' ' || ch == '}' || ch == ']' || ch == ':') break;
currpos++;
}
if (currpos == start) throw new ConvertException("expected a string after a key but '" + text0[position] + "' (position = " + position + ") in (" + new String(this.text) + ")");
this.position = currpos - 1;
return new String(text0, start, currpos - start);
}
this.position = currpos;
throw new ConvertException("expected a ':' after a key but '" + text0[position] + "' (position = " + position + ") in (" + new String(this.text) + ")");
}
final int start = ++currpos;
for (;;) {
char ch = text0[currpos];
if (ch == expected) {
break;
} else if (ch == '\\') {
this.position = currpos - 1;
return readEscapeValue(expected, start);
}
currpos++;
}
this.position = currpos;
return new String(text0, start, currpos - start);
}
private String readEscapeValue(final char expected, int start) {
StringBuilder array = new StringBuilder();
final char[] text0 = this.text;
int pos = this.position;
array.append(text0, start, pos + 1 - start);
char c;
for (;;) {
c = text0[++pos];
if (c == expected) {
this.position = pos;
return array.toString();
} else if (c == '\\') {
c = text0[++pos];
switch (c) {
case '"':
case '\'':
case '\\':
case '/':
array.append(c);
break;
case 'n':
array.append('\n');
break;
case 'r':
array.append('\r');
break;
case 'u':
array.append((char) Integer.parseInt(new String(new char[]{text0[++pos], text0[++pos], text0[++pos], text0[++pos]}), 16));
break;
case 't':
array.append('\t');
break;
case 'b':
array.append('\b');
break;
case 'f':
array.append('\f');
break;
default:
this.position = pos;
throw new ConvertException("illegal escape(" + c + ") (position = " + this.position + ") in (" + new String(this.text) + ")");
}
} else {
array.append(c);
}
}
}
final static int[] digits = new int[255];
static {
for (int i = 0; i < digits.length; i++) {
digits[i] = -1; //-1 错误
}
for (int i = '0'; i <= '9'; i++) {
digits[i] = i - '0';
}
for (int i = 'a'; i <= 'f'; i++) {
digits[i] = i - 'a' + 10;
}
for (int i = 'A'; i <= 'F'; i++) {
digits[i] = i - 'A' + 10;
}
digits['"'] = digits['\''] = -2; //-2 跳过
digits[' '] = digits['\t'] = digits['\r'] = digits['\n'] = -3; //-3可能跳过
digits[','] = digits['}'] = digits[']'] = digits[':'] = -4; //-4退出
}
}