org.redkale.convert.json.JsonByteBufferReader Maven / Gradle / Ivy
/*
* To change this license header, choose License Headers in Project Properties.
* To change this template file, choose Tools | Templates
* and open the template in the editor.
*/
package org.redkale.convert.json;
import java.nio.*;
import java.nio.charset.*;
import org.redkale.convert.*;
import static org.redkale.convert.Reader.*;
/**
* 以ByteBuffer为数据载体的JsonReader
*
* 只支持UTF-8格式
*
* 详情见: https://redkale.org
*
* @author zhangjx
*/
public class JsonByteBufferReader extends JsonReader {
private char currentChar;
private ByteBuffer[] buffers;
private int currentIndex = 0;
private ByteBuffer currentBuffer;
protected ConvertMask mask;
protected JsonByteBufferReader(ConvertMask mask, ByteBuffer... buffers) {
this.mask = mask;
this.buffers = buffers;
if (buffers != null && buffers.length > 0) this.currentBuffer = buffers[currentIndex];
}
@Override
protected boolean recycle() {
super.recycle(); // this.position 初始化值为-1
this.currentIndex = 0;
this.currentChar = 0;
this.currentBuffer = null;
this.buffers = null;
this.mask = null;
return false;
}
protected byte nextByte() {
if (this.currentBuffer.hasRemaining()) {
this.position++;
return mask == null ? this.currentBuffer.get() : mask.unmask(this.currentBuffer.get());
}
for (;;) {
this.currentBuffer = this.buffers[++this.currentIndex];
if (this.currentBuffer.hasRemaining()) {
this.position++;
return mask == null ? this.currentBuffer.get() : mask.unmask(this.currentBuffer.get());
}
}
}
/**
* 读取下一个字符， 不跳过空白字符
*
* @return 有效字符或空白字符
*/
@Override
protected final char nextChar() {
if (currentChar != 0) {
char ch = currentChar;
this.currentChar = 0;
return ch;
}
if (this.currentBuffer != null) {
int remain = this.currentBuffer.remaining();
if (remain == 0 && this.currentIndex + 1 >= this.buffers.length) return 0;
}
byte b1 = nextByte();
if (b1 >= 0) {// 1 byte, 7 bits: 0xxxxxxx
return (char) b1;
} else if ((b1 >> 5) == -2 && (b1 & 0x1e) != 0) { // 2 bytes, 11 bits: 110xxxxx 10xxxxxx
return (char) (((b1 << 6) ^ nextByte()) ^ (((byte) 0xC0 << 6) ^ ((byte) 0x80)));
} else if ((b1 >> 4) == -2) { // 3 bytes, 16 bits: 1110xxxx 10xxxxxx 10xxxxxx
return (char) ((b1 << 12) ^ (nextByte() << 6) ^ (nextByte() ^ (((byte) 0xE0 << 12) ^ ((byte) 0x80 << 6) ^ ((byte) 0x80))));
} else { // 4 bytes, 21 bits: 11110xxx 10xxxxxx 10xxxxxx 10xxxxxx
throw new RuntimeException(new UnmappableCharacterException(4));
}
}
/**
* 读取下一个有效字符
*
* @return 有效字符
*/
@Override
protected final char nextGoodChar() {
char c = nextChar();
if (c > ' ' || c == 0) return c; // 0 表示buffer结尾了
for (;;) {
c = nextChar();
if (c > ' ' || c == 0) return c;
}
}
/**
* 回退最后读取的字符
*
* @param ch 回退的字符
*/
@Override
protected final void backChar(char ch) {
this.currentChar = ch;
}
/**
* 判断下一个非空白字符是否为{
*
* @return SIGN_NOLENGTH 或 SIGN_NULL
*/
@Override
public final String readObjectB(final Class clazz) {
char ch = nextGoodChar();
if (ch == '{') return "";
if (ch == 'n' && nextChar() == 'u' && nextChar() == 'l' && nextChar() == 'l') return null;
if (ch == 'N' && nextChar() == 'U' && nextChar() == 'L' && nextChar() == 'L') return null;
StringBuilder sb = new StringBuilder();
sb.append(ch);
char one;
try {
while ((one = nextChar()) != 0) sb.append(one);
} catch (Exception e) {
}
throw new ConvertException("a json object text must begin with '{' (position = " + position + ") but '" + ch + "' in (" + sb + ")");
}
/**
* 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 final int readArrayB(DeMember member, Decodeable decoder) {
char ch = nextGoodChar();
if (ch == '[' || ch == '{') return SIGN_NOLENGTH;
if (ch == 'n' && nextChar() == 'u' && nextChar() == 'l' && nextChar() == 'l') return SIGN_NULL;
if (ch == 'N' && nextChar() == 'U' && nextChar() == 'L' && nextChar() == 'L') return SIGN_NULL;
StringBuilder sb = new StringBuilder();
sb.append(ch);
char one;
try {
while ((one = nextChar()) != 0) sb.append(one);
} catch (Exception e) {
}
throw new ConvertException("a json array text must begin with '[' (position = " + position + ") but '" + ch + "' in (" + sb + ")");
}
/**
* 判断下一个非空白字符是否:
*/
@Override
public final void readBlank() {
char ch = nextGoodChar();
if (ch == ':') return;
StringBuilder sb = new StringBuilder();
sb.append(ch);
char one;
try {
while ((one = nextChar()) != 0) sb.append(one);
} catch (Exception e) {
}
throw new ConvertException("expected a ':' but '" + ch + "'(position = " + position + ") in (" + sb + ")");
}
/**
* 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 = nextGoodChar();
if (ch == ',') return true;
if (ch == '}' || ch == ']' || ch == 0) return false;
backChar(ch); // { [ 交由 readObjectB 或 readMapB 或 readArrayB 读取
return true;
}
/**
* 读取小字符串
*
* @return String值
*/
@Override
public final String readSmallString() {
char ch = nextGoodChar();
if (ch == 0) return null;
final StringBuilder sb = new StringBuilder();
if (ch == '"' || ch == '\'') {
final char quote = ch;
for (;;) {
ch = nextChar();
if (ch == '\\') {
char c = nextChar();
switch (c) {
case '"':
case '\'':
case '\\':
case '/':
sb.append(c);
break;
case 'n':
sb.append('\n');
break;
case 'r':
sb.append('\r');
break;
case 'u':
sb.append((char) Integer.parseInt(new String(new char[]{nextChar(), nextChar(), nextChar(), nextChar()}), 16));
break;
case 't':
sb.append('\t');
break;
case 'b':
sb.append('\b');
break;
case 'f':
sb.append('\f');
break;
default:
throw new ConvertException("illegal escape(" + c + ") (position = " + this.position + ")");
}
} else if (ch == quote || ch == 0) {
break;
} else {
sb.append(ch);
}
}
return sb.toString();
} else {
sb.append(ch);
for (;;) {
ch = nextChar();
if (ch == '\\') {
char c = nextChar();
switch (c) {
case '"':
case '\'':
case '\\':
case '/':
sb.append(c);
break;
case 'n':
sb.append('\n');
break;
case 'r':
sb.append('\r');
break;
case 'u':
sb.append((char) Integer.parseInt(new String(new char[]{nextChar(), nextChar(), nextChar(), nextChar()}), 16));
break;
case 't':
sb.append('\t');
break;
case 'b':
sb.append('\b');
break;
case 'f':
sb.append('\f');
break;
default:
throw new ConvertException("illegal escape(" + c + ") (position = " + this.position + ")");
}
} else if (ch == ',' || ch == ']' || ch == '}' || ch <= ' ' || ch == ':') { // ch <= ' ' 包含 0
backChar(ch);
break;
} else {
sb.append(ch);
}
}
String rs = sb.toString();
return "null".equalsIgnoreCase(rs) ? null : rs;
}
}
/**
* 读取一个int值
*
* @return int值
*/
@Override
public final int readInt() {
char firstchar = nextGoodChar();
boolean quote = false;
if (firstchar == '"' || firstchar == '\'') {
quote = true;
firstchar = nextGoodChar();
if (firstchar == '"' || firstchar == '\'') return 0;
}
int value = 0;
final boolean negative = firstchar == '-';
if (!negative) {
if (firstchar < '0' || firstchar > '9') throw new ConvertException("illegal escape(" + firstchar + ") (position = " + position + ")");
value = firstchar - '0';
}
for (;;) {
char ch = nextChar();
if (ch == 0) break;
if (ch >= '0' && ch <= '9') {
value = (value << 3) + (value << 1) + (ch - '0');
} else if (ch == '"' || ch == '\'') {
} else if (quote && ch <= ' ') {
} else if (ch == ',' || ch == '}' || ch == ']' || ch <= ' ' || ch == ':') {
backChar(ch);
break;
} else {
throw new ConvertException("illegal escape(" + ch + ") (position = " + position + ")");
}
}
return negative ? -value : value;
}
/**
* 读取一个long值
*
* @return long值
*/
@Override
public final long readLong() {
char firstchar = nextGoodChar();
boolean quote = false;
if (firstchar == '"' || firstchar == '\'') {
quote = true;
firstchar = nextGoodChar();
if (firstchar == '"' || firstchar == '\'') return 0L;
}
long value = 0;
final boolean negative = firstchar == '-';
if (!negative) {
if (firstchar < '0' || firstchar > '9') throw new ConvertException("illegal escape(" + firstchar + ") (position = " + position + ")");
value = firstchar - '0';
}
for (;;) {
char ch = nextChar();
if (ch == 0) break;
if (ch >= '0' && ch <= '9') {
value = (value << 3) + (value << 1) + (ch - '0');
} else if (ch == '"' || ch == '\'') {
} else if (quote && ch <= ' ') {
} else if (ch == ',' || ch == '}' || ch == ']' || ch <= ' ' || ch == ':') {
backChar(ch);
break;
} else {
throw new ConvertException("illegal escape(" + ch + ") (position = " + position + ")");
}
}
return negative ? -value : value;
}
/**
* 读取字符串， 必须是"或者'包围的字符串值
*
* @return String值
*/
@Override
public final String readString() {
return readSmallString();
}
}