/*
* Copyright (C) 2010 Google Inc.
*
* Licensed under the Apache License, 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.apache.org/licenses/LICENSE-2.0
*
* 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 com.apollographql.apollo.internal.json;
import com.apollographql.apollo.json.JsonDataException;
import com.apollographql.apollo.json.JsonEncodingException;
import java.io.EOFException;
import java.io.IOException;
import okio.Buffer;
import okio.BufferedSource;
import okio.ByteString;
/** TODO add Modifications copyright **/
public final class BufferedSourceJsonReader extends JsonReader {
private static final long MIN_INCOMPLETE_INTEGER = Long.MIN_VALUE / 10;
private static final ByteString SINGLE_QUOTE_OR_SLASH = ByteString.encodeUtf8("'\\");
private static final ByteString DOUBLE_QUOTE_OR_SLASH = ByteString.encodeUtf8("\"\\");
private static final ByteString UNQUOTED_STRING_TERMINALS
= ByteString.encodeUtf8("{}[]:, \n\t\r\f/\\;#=");
private static final ByteString LINEFEED_OR_CARRIAGE_RETURN = ByteString.encodeUtf8("\n\r");
private static final int PEEKED_NONE = 0;
private static final int PEEKED_BEGIN_OBJECT = 1;
private static final int PEEKED_END_OBJECT = 2;
private static final int PEEKED_BEGIN_ARRAY = 3;
private static final int PEEKED_END_ARRAY = 4;
private static final int PEEKED_TRUE = 5;
private static final int PEEKED_FALSE = 6;
private static final int PEEKED_NULL = 7;
private static final int PEEKED_SINGLE_QUOTED = 8;
private static final int PEEKED_DOUBLE_QUOTED = 9;
private static final int PEEKED_UNQUOTED = 10;
/** When this is returned, the string value is stored in peekedString. */
private static final int PEEKED_BUFFERED = 11;
private static final int PEEKED_SINGLE_QUOTED_NAME = 12;
private static final int PEEKED_DOUBLE_QUOTED_NAME = 13;
private static final int PEEKED_UNQUOTED_NAME = 14;
/** When this is returned, the integer value is stored in peekedLong. */
private static final int PEEKED_LONG = 15;
private static final int PEEKED_NUMBER = 16;
private static final int PEEKED_EOF = 17;
/* State machine when parsing numbers */
private static final int NUMBER_CHAR_NONE = 0;
private static final int NUMBER_CHAR_SIGN = 1;
private static final int NUMBER_CHAR_DIGIT = 2;
private static final int NUMBER_CHAR_DECIMAL = 3;
private static final int NUMBER_CHAR_FRACTION_DIGIT = 4;
private static final int NUMBER_CHAR_EXP_E = 5;
private static final int NUMBER_CHAR_EXP_SIGN = 6;
private static final int NUMBER_CHAR_EXP_DIGIT = 7;
/** True to accept non-spec compliant JSON */
private boolean lenient = false;
/** True to throw a {@link JsonDataException} on any attempt to call {@link #skipValue()}. */
private boolean failOnUnknown = false;
/** The input JSON. */
private final BufferedSource source;
private final Buffer buffer;
private int peeked = PEEKED_NONE;
/**
* A peeked value that was composed entirely of digits with an optional
* leading dash. Positive values may not have a leading 0.
*/
private long peekedLong;
/**
* The number of characters in a peeked number literal. Increment 'pos' by
* this after reading a number.
*/
private int peekedNumberLength;
/**
* A peeked string that should be parsed on the next double, long or string.
* This is populated before a numeric value is parsed and used if that parsing
* fails.
*/
private String peekedString;
// The nesting stack. Using a manual array rather than an ArrayList saves 20%. This stack permits
// up to 32 levels of nesting including the top-level document. Deeper nesting is prone to trigger
// StackOverflowErrors.
private final int[] stack = new int[32];
private int stackSize = 0;
{
stack[stackSize++] = JsonScope.EMPTY_DOCUMENT;
}
private final String[] pathNames = new String[32];
private final int[] pathIndices = new int[32];
public BufferedSourceJsonReader(BufferedSource source) {
if (source == null) {
throw new NullPointerException("source == null");
}
this.source = source;
this.buffer = source.buffer();
}
@Override public void setLenient(boolean lenient) {
this.lenient = lenient;
}
@Override public boolean isLenient() {
return lenient;
}
@Override public void setFailOnUnknown(boolean failOnUnknown) {
this.failOnUnknown = failOnUnknown;
}
@Override public boolean failOnUnknown() {
return failOnUnknown;
}
@Override public void beginArray() throws IOException {
int p = peeked;
if (p == PEEKED_NONE) {
p = doPeek();
}
if (p == PEEKED_BEGIN_ARRAY) {
push(JsonScope.EMPTY_ARRAY);
pathIndices[stackSize - 1] = 0;
peeked = PEEKED_NONE;
} else {
throw new JsonDataException("Expected BEGIN_ARRAY but was " + peek()
+ " at path " + getPath());
}
}
@Override public void endArray() throws IOException {
int p = peeked;
if (p == PEEKED_NONE) {
p = doPeek();
}
if (p == PEEKED_END_ARRAY) {
stackSize--;
pathIndices[stackSize - 1]++;
peeked = PEEKED_NONE;
} else {
throw new JsonDataException("Expected END_ARRAY but was " + peek()
+ " at path " + getPath());
}
}
@Override public void beginObject() throws IOException {
int p = peeked;
if (p == PEEKED_NONE) {
p = doPeek();
}
if (p == PEEKED_BEGIN_OBJECT) {
push(JsonScope.EMPTY_OBJECT);
peeked = PEEKED_NONE;
} else {
throw new JsonDataException("Expected BEGIN_OBJECT but was " + peek()
+ " at path " + getPath());
}
}
@Override public void endObject() throws IOException {
int p = peeked;
if (p == PEEKED_NONE) {
p = doPeek();
}
if (p == PEEKED_END_OBJECT) {
stackSize--;
pathNames[stackSize] = null; // Free the last path name so that it can be garbage collected!
pathIndices[stackSize - 1]++;
peeked = PEEKED_NONE;
} else {
throw new JsonDataException("Expected END_OBJECT but was " + peek()
+ " at path " + getPath());
}
}
@Override public boolean hasNext() throws IOException {
int p = peeked;
if (p == PEEKED_NONE) {
p = doPeek();
}
return p != PEEKED_END_OBJECT && p != PEEKED_END_ARRAY;
}
@Override public Token peek() throws IOException {
int p = peeked;
if (p == PEEKED_NONE) {
p = doPeek();
}
switch (p) {
case PEEKED_BEGIN_OBJECT:
return Token.BEGIN_OBJECT;
case PEEKED_END_OBJECT:
return Token.END_OBJECT;
case PEEKED_BEGIN_ARRAY:
return Token.BEGIN_ARRAY;
case PEEKED_END_ARRAY:
return Token.END_ARRAY;
case PEEKED_SINGLE_QUOTED_NAME:
case PEEKED_DOUBLE_QUOTED_NAME:
case PEEKED_UNQUOTED_NAME:
return Token.NAME;
case PEEKED_TRUE:
case PEEKED_FALSE:
return Token.BOOLEAN;
case PEEKED_NULL:
return Token.NULL;
case PEEKED_SINGLE_QUOTED:
case PEEKED_DOUBLE_QUOTED:
case PEEKED_UNQUOTED:
case PEEKED_BUFFERED:
return Token.STRING;
case PEEKED_LONG:
case PEEKED_NUMBER:
return Token.NUMBER;
case PEEKED_EOF:
return Token.END_DOCUMENT;
default:
throw new AssertionError();
}
}
private int doPeek() throws IOException {
int peekStack = stack[stackSize - 1];
if (peekStack == JsonScope.EMPTY_ARRAY) {
stack[stackSize - 1] = JsonScope.NONEMPTY_ARRAY;
} else if (peekStack == JsonScope.NONEMPTY_ARRAY) {
// Look for a comma before the next element.
int c = nextNonWhitespace(true);
buffer.readByte(); // consume ']' or ','.
switch (c) {
case ']':
return peeked = PEEKED_END_ARRAY;
case ';':
checkLenient(); // fall-through
case ',':
break;
default:
throw syntaxError("Unterminated array");
}
} else if (peekStack == JsonScope.EMPTY_OBJECT || peekStack == JsonScope.NONEMPTY_OBJECT) {
stack[stackSize - 1] = JsonScope.DANGLING_NAME;
// Look for a comma before the next element.
if (peekStack == JsonScope.NONEMPTY_OBJECT) {
int c = nextNonWhitespace(true);
buffer.readByte(); // Consume '}' or ','.
switch (c) {
case '}':
return peeked = PEEKED_END_OBJECT;
case ';':
checkLenient(); // fall-through
case ',':
break;
default:
throw syntaxError("Unterminated object");
}
}
int c = nextNonWhitespace(true);
switch (c) {
case '"':
buffer.readByte(); // consume the '\"'.
return peeked = PEEKED_DOUBLE_QUOTED_NAME;
case '\'':
buffer.readByte(); // consume the '\''.
checkLenient();
return peeked = PEEKED_SINGLE_QUOTED_NAME;
case '}':
if (peekStack != JsonScope.NONEMPTY_OBJECT) {
buffer.readByte(); // consume the '}'.
return peeked = PEEKED_END_OBJECT;
} else {
throw syntaxError("Expected name");
}
default:
checkLenient();
if (isLiteral((char) c)) {
return peeked = PEEKED_UNQUOTED_NAME;
} else {
throw syntaxError("Expected name");
}
}
} else if (peekStack == JsonScope.DANGLING_NAME) {
stack[stackSize - 1] = JsonScope.NONEMPTY_OBJECT;
// Look for a colon before the value.
int c = nextNonWhitespace(true);
buffer.readByte(); // Consume ':'.
switch (c) {
case ':':
break;
case '=':
checkLenient();
if (source.request(1) && buffer.getByte(0) == '>') {
buffer.readByte(); // Consume '>'.
}
break;
default:
throw syntaxError("Expected ':'");
}
} else if (peekStack == JsonScope.EMPTY_DOCUMENT) {
stack[stackSize - 1] = JsonScope.NONEMPTY_DOCUMENT;
} else if (peekStack == JsonScope.NONEMPTY_DOCUMENT) {
int c = nextNonWhitespace(false);
if (c == -1) {
return peeked = PEEKED_EOF;
} else {
checkLenient();
}
} else if (peekStack == JsonScope.CLOSED) {
throw new IllegalStateException("JsonReader is closed");
}
int c = nextNonWhitespace(true);
switch (c) {
case ']':
if (peekStack == JsonScope.EMPTY_ARRAY) {
buffer.readByte(); // Consume ']'.
return peeked = PEEKED_END_ARRAY;
}
// fall-through to handle ",]"
case ';':
case ',':
// In lenient mode, a 0-length literal in an array means 'null'.
if (peekStack == JsonScope.EMPTY_ARRAY || peekStack == JsonScope.NONEMPTY_ARRAY) {
checkLenient();
return peeked = PEEKED_NULL;
} else {
throw syntaxError("Unexpected value");
}
case '\'':
checkLenient();
buffer.readByte(); // Consume '\''.
return peeked = PEEKED_SINGLE_QUOTED;
case '"':
buffer.readByte(); // Consume '\"'.
return peeked = PEEKED_DOUBLE_QUOTED;
case '[':
buffer.readByte(); // Consume '['.
return peeked = PEEKED_BEGIN_ARRAY;
case '{':
buffer.readByte(); // Consume '{'.
return peeked = PEEKED_BEGIN_OBJECT;
default:
}
int result = peekKeyword();
if (result != PEEKED_NONE) {
return result;
}
result = peekNumber();
if (result != PEEKED_NONE) {
return result;
}
if (!isLiteral(buffer.getByte(0))) {
throw syntaxError("Expected value");
}
checkLenient();
return peeked = PEEKED_UNQUOTED;
}
private int peekKeyword() throws IOException {
// Figure out which keyword we're matching against by its first character.
byte c = buffer.getByte(0);
String keyword;
String keywordUpper;
int peeking;
if (c == 't' || c == 'T') {
keyword = "true";
keywordUpper = "TRUE";
peeking = PEEKED_TRUE;
} else if (c == 'f' || c == 'F') {
keyword = "false";
keywordUpper = "FALSE";
peeking = PEEKED_FALSE;
} else if (c == 'n' || c == 'N') {
keyword = "null";
keywordUpper = "NULL";
peeking = PEEKED_NULL;
} else {
return PEEKED_NONE;
}
// Confirm that chars [1..length) match the keyword.
int length = keyword.length();
for (int i = 1; i < length; i++) {
if (!source.request(i + 1)) {
return PEEKED_NONE;
}
c = buffer.getByte(i);
if (c != keyword.charAt(i) && c != keywordUpper.charAt(i)) {
return PEEKED_NONE;
}
}
if (source.request(length + 1) && isLiteral(buffer.getByte(length))) {
return PEEKED_NONE; // Don't match trues, falsey or nullsoft!
}
// We've found the keyword followed either by EOF or by a non-literal character.
buffer.skip(length);
return peeked = peeking;
}
private int peekNumber() throws IOException {
long value = 0; // Negative to accommodate Long.MIN_VALUE more easily.
boolean negative = false;
boolean fitsInLong = true;
int last = NUMBER_CHAR_NONE;
int i = 0;
charactersOfNumber:
for (; true; i++) {
if (!source.request(i + 1)) {
break;
}
byte c = buffer.getByte(i);
switch (c) {
case '-':
if (last == NUMBER_CHAR_NONE) {
negative = true;
last = NUMBER_CHAR_SIGN;
continue;
} else if (last == NUMBER_CHAR_EXP_E) {
last = NUMBER_CHAR_EXP_SIGN;
continue;
}
return PEEKED_NONE;
case '+':
if (last == NUMBER_CHAR_EXP_E) {
last = NUMBER_CHAR_EXP_SIGN;
continue;
}
return PEEKED_NONE;
case 'e':
case 'E':
if (last == NUMBER_CHAR_DIGIT || last == NUMBER_CHAR_FRACTION_DIGIT) {
last = NUMBER_CHAR_EXP_E;
continue;
}
return PEEKED_NONE;
case '.':
if (last == NUMBER_CHAR_DIGIT) {
last = NUMBER_CHAR_DECIMAL;
continue;
}
return PEEKED_NONE;
default:
if (c < '0' || c > '9') {
if (!isLiteral(c)) {
break charactersOfNumber;
}
return PEEKED_NONE;
}
if (last == NUMBER_CHAR_SIGN || last == NUMBER_CHAR_NONE) {
value = -(c - '0');
last = NUMBER_CHAR_DIGIT;
} else if (last == NUMBER_CHAR_DIGIT) {
if (value == 0) {
return PEEKED_NONE; // Leading '0' prefix is not allowed (since it could be octal).
}
long newValue = value * 10 - (c - '0');
fitsInLong &= value > MIN_INCOMPLETE_INTEGER
|| (value == MIN_INCOMPLETE_INTEGER && newValue < value);
value = newValue;
} else if (last == NUMBER_CHAR_DECIMAL) {
last = NUMBER_CHAR_FRACTION_DIGIT;
} else if (last == NUMBER_CHAR_EXP_E || last == NUMBER_CHAR_EXP_SIGN) {
last = NUMBER_CHAR_EXP_DIGIT;
}
}
}
// We've read a complete number. Decide if it's a PEEKED_LONG or a PEEKED_NUMBER.
if (last == NUMBER_CHAR_DIGIT && fitsInLong && (value != Long.MIN_VALUE || negative)) {
peekedLong = negative ? value : -value;
buffer.skip(i);
return peeked = PEEKED_LONG;
} else if (last == NUMBER_CHAR_DIGIT || last == NUMBER_CHAR_FRACTION_DIGIT
|| last == NUMBER_CHAR_EXP_DIGIT) {
peekedNumberLength = i;
return peeked = PEEKED_NUMBER;
} else {
return PEEKED_NONE;
}
}
private boolean isLiteral(int c) throws IOException {
switch (c) {
case '/':
case '\\':
case ';':
case '#':
case '=':
checkLenient(); // fall-through
case '{':
case '}':
case '[':
case ']':
case ':':
case ',':
case ' ':
case '\t':
case '\f':
case '\r':
case '\n':
return false;
default:
return true;
}
}
@Override public String nextName() throws IOException {
int p = peeked;
if (p == PEEKED_NONE) {
p = doPeek();
}
String result;
if (p == PEEKED_UNQUOTED_NAME) {
result = nextUnquotedValue();
} else if (p == PEEKED_DOUBLE_QUOTED_NAME) {
result = nextQuotedValue(DOUBLE_QUOTE_OR_SLASH);
} else if (p == PEEKED_SINGLE_QUOTED_NAME) {
result = nextQuotedValue(SINGLE_QUOTE_OR_SLASH);
} else {
throw new JsonDataException("Expected a name but was " + peek() + " at path " + getPath());
}
peeked = PEEKED_NONE;
pathNames[stackSize - 1] = result;
return result;
}
@Override public String nextString() throws IOException {
int p = peeked;
if (p == PEEKED_NONE) {
p = doPeek();
}
String result;
if (p == PEEKED_UNQUOTED) {
result = nextUnquotedValue();
} else if (p == PEEKED_DOUBLE_QUOTED) {
result = nextQuotedValue(DOUBLE_QUOTE_OR_SLASH);
} else if (p == PEEKED_SINGLE_QUOTED) {
result = nextQuotedValue(SINGLE_QUOTE_OR_SLASH);
} else if (p == PEEKED_BUFFERED) {
result = peekedString;
peekedString = null;
} else if (p == PEEKED_LONG) {
result = Long.toString(peekedLong);
} else if (p == PEEKED_NUMBER) {
result = buffer.readUtf8(peekedNumberLength);
} else {
throw new JsonDataException("Expected a string but was " + peek() + " at path " + getPath());
}
peeked = PEEKED_NONE;
pathIndices[stackSize - 1]++;
return result;
}
@Override public boolean nextBoolean() throws IOException {
int p = peeked;
if (p == PEEKED_NONE) {
p = doPeek();
}
if (p == PEEKED_TRUE) {
peeked = PEEKED_NONE;
pathIndices[stackSize - 1]++;
return true;
} else if (p == PEEKED_FALSE) {
peeked = PEEKED_NONE;
pathIndices[stackSize - 1]++;
return false;
}
throw new JsonDataException("Expected a boolean but was " + peek() + " at path " + getPath());
}
@Override public <T> T nextNull() throws IOException {
int p = peeked;
if (p == PEEKED_NONE) {
p = doPeek();
}
if (p == PEEKED_NULL) {
peeked = PEEKED_NONE;
pathIndices[stackSize - 1]++;
return null;
} else {
throw new JsonDataException("Expected null but was " + peek() + " at path " + getPath());
}
}
@Override public double nextDouble() throws IOException {
int p = peeked;
if (p == PEEKED_NONE) {
p = doPeek();
}
if (p == PEEKED_LONG) {
peeked = PEEKED_NONE;
pathIndices[stackSize - 1]++;
return (double) peekedLong;
}
if (p == PEEKED_NUMBER) {
peekedString = buffer.readUtf8(peekedNumberLength);
} else if (p == PEEKED_DOUBLE_QUOTED) {
peekedString = nextQuotedValue(DOUBLE_QUOTE_OR_SLASH);
} else if (p == PEEKED_SINGLE_QUOTED) {
peekedString = nextQuotedValue(SINGLE_QUOTE_OR_SLASH);
} else if (p == PEEKED_UNQUOTED) {
peekedString = nextUnquotedValue();
} else if (p != PEEKED_BUFFERED) {
throw new JsonDataException("Expected a double but was " + peek() + " at path " + getPath());
}
peeked = PEEKED_BUFFERED;
double result;
try {
result = Double.parseDouble(peekedString);
} catch (NumberFormatException e) {
throw new JsonDataException("Expected a double but was " + peekedString
+ " at path " + getPath());
}
if (!lenient && (Double.isNaN(result) || Double.isInfinite(result))) {
throw new JsonEncodingException("JSON forbids NaN and infinities: " + result
+ " at path " + getPath());
}
peekedString = null;
peeked = PEEKED_NONE;
pathIndices[stackSize - 1]++;
return result;
}
@Override public long nextLong() throws IOException {
int p = peeked;
if (p == PEEKED_NONE) {
p = doPeek();
}
if (p == PEEKED_LONG) {
peeked = PEEKED_NONE;
pathIndices[stackSize - 1]++;
return peekedLong;
}
if (p == PEEKED_NUMBER) {
peekedString = buffer.readUtf8(peekedNumberLength);
} else if (p == PEEKED_DOUBLE_QUOTED || p == PEEKED_SINGLE_QUOTED) {
peekedString = p == PEEKED_DOUBLE_QUOTED
? nextQuotedValue(DOUBLE_QUOTE_OR_SLASH)
: nextQuotedValue(SINGLE_QUOTE_OR_SLASH);
try {
long result = Long.parseLong(peekedString);
peeked = PEEKED_NONE;
pathIndices[stackSize - 1]++;
return result;
} catch (NumberFormatException ignored) {
// Fall back to parse as a double below.
}
} else if (p != PEEKED_BUFFERED) {
throw new JsonDataException("Expected a long but was " + peek()
+ " at path " + getPath());
}
peeked = PEEKED_BUFFERED;
double asDouble;
try {
asDouble = Double.parseDouble(peekedString);
} catch (NumberFormatException e) {
throw new JsonDataException("Expected a long but was " + peekedString
+ " at path " + getPath());
}
long result = (long) asDouble;
if (result != asDouble) { // Make sure no precision was lost casting to 'long'.
throw new JsonDataException("Expected a long but was " + peekedString
+ " at path " + getPath());
}
peekedString = null;
peeked = PEEKED_NONE;
pathIndices[stackSize - 1]++;
return result;
}
/**
* Returns the string up to but not including {@code quote}, unescaping any character escape
* sequences encountered along the way. The opening quote should have already been read. This
* consumes the closing quote, but does not include it in the returned string.
*
* @throws IOException if any unicode escape sequences are malformed.
*/
private String nextQuotedValue(ByteString runTerminator) throws IOException {
StringBuilder builder = null;
while (true) {
long index = source.indexOfElement(runTerminator);
if (index == -1L) throw syntaxError("Unterminated string");
// If we've got an escape character, we're going to need a string builder.
if (buffer.getByte(index) == '\\') {
if (builder == null) builder = new StringBuilder();
builder.append(buffer.readUtf8(index));
buffer.readByte(); // '\'
builder.append(readEscapeCharacter());
continue;
}
// If it isn't the escape character, it's the quote. Return the string.
if (builder == null) {
String result = buffer.readUtf8(index);
buffer.readByte(); // Consume the quote character.
return result;
} else {
builder.append(buffer.readUtf8(index));
buffer.readByte(); // Consume the quote character.
return builder.toString();
}
}
}
/** Returns an unquoted value as a string. */
private String nextUnquotedValue() throws IOException {
long i = source.indexOfElement(UNQUOTED_STRING_TERMINALS);
return i != -1 ? buffer.readUtf8(i) : buffer.readUtf8();
}
private void skipQuotedValue(ByteString runTerminator) throws IOException {
while (true) {
long index = source.indexOfElement(runTerminator);
if (index == -1L) throw syntaxError("Unterminated string");
if (buffer.getByte(index) == '\\') {
buffer.skip(index + 1);
readEscapeCharacter();
} else {
buffer.skip(index + 1);
return;
}
}
}
private void skipUnquotedValue() throws IOException {
long i = source.indexOfElement(UNQUOTED_STRING_TERMINALS);
buffer.skip(i != -1L ? i : buffer.size());
}
@Override public int nextInt() throws IOException {
int p = peeked;
if (p == PEEKED_NONE) {
p = doPeek();
}
int result;
if (p == PEEKED_LONG) {
result = (int) peekedLong;
if (peekedLong != result) { // Make sure no precision was lost casting to 'int'.
throw new JsonDataException("Expected an int but was " + peekedLong
+ " at path " + getPath());
}
peeked = PEEKED_NONE;
pathIndices[stackSize - 1]++;
return result;
}
if (p == PEEKED_NUMBER) {
peekedString = buffer.readUtf8(peekedNumberLength);
} else if (p == PEEKED_DOUBLE_QUOTED || p == PEEKED_SINGLE_QUOTED) {
peekedString = p == PEEKED_DOUBLE_QUOTED
? nextQuotedValue(DOUBLE_QUOTE_OR_SLASH)
: nextQuotedValue(SINGLE_QUOTE_OR_SLASH);
try {
result = Integer.parseInt(peekedString);
peeked = PEEKED_NONE;
pathIndices[stackSize - 1]++;
return result;
} catch (NumberFormatException ignored) {
// Fall back to parse as a double below.
}
} else if (p != PEEKED_BUFFERED) {
throw new JsonDataException("Expected an int but was " + peek() + " at path " + getPath());
}
peeked = PEEKED_BUFFERED;
double asDouble;
try {
asDouble = Double.parseDouble(peekedString);
} catch (NumberFormatException e) {
throw new JsonDataException("Expected an int but was " + peekedString
+ " at path " + getPath());
}
result = (int) asDouble;
if (result != asDouble) { // Make sure no precision was lost casting to 'int'.
throw new JsonDataException("Expected an int but was " + peekedString
+ " at path " + getPath());
}
peekedString = null;
peeked = PEEKED_NONE;
pathIndices[stackSize - 1]++;
return result;
}
@Override public void close() throws IOException {
peeked = PEEKED_NONE;
stack[0] = JsonScope.CLOSED;
stackSize = 1;
buffer.clear();
source.close();
}
@Override public void skipValue() throws IOException {
if (failOnUnknown) {
throw new JsonDataException("Cannot skip unexpected " + peek() + " at " + getPath());
}
int count = 0;
do {
int p = peeked;
if (p == PEEKED_NONE) {
p = doPeek();
}
if (p == PEEKED_BEGIN_ARRAY) {
push(JsonScope.EMPTY_ARRAY);
count++;
} else if (p == PEEKED_BEGIN_OBJECT) {
push(JsonScope.EMPTY_OBJECT);
count++;
} else if (p == PEEKED_END_ARRAY) {
stackSize--;
count--;
} else if (p == PEEKED_END_OBJECT) {
stackSize--;
count--;
} else if (p == PEEKED_UNQUOTED_NAME || p == PEEKED_UNQUOTED) {
skipUnquotedValue();
} else if (p == PEEKED_DOUBLE_QUOTED || p == PEEKED_DOUBLE_QUOTED_NAME) {
skipQuotedValue(DOUBLE_QUOTE_OR_SLASH);
} else if (p == PEEKED_SINGLE_QUOTED || p == PEEKED_SINGLE_QUOTED_NAME) {
skipQuotedValue(SINGLE_QUOTE_OR_SLASH);
} else if (p == PEEKED_NUMBER) {
buffer.skip(peekedNumberLength);
}
peeked = PEEKED_NONE;
} while (count != 0);
pathIndices[stackSize - 1]++;
pathNames[stackSize - 1] = "null";
}
private void push(int newTop) {
if (stackSize == stack.length) {
throw new JsonDataException("Nesting too deep at " + getPath());
}
stack[stackSize++] = newTop;
}
/**
* Returns the next character in the stream that is neither whitespace nor a
* part of a comment. When this returns, the returned character is always at
* {@code buffer[pos-1]}; this means the caller can always push back the
* returned character by decrementing {@code pos}.
*/
private int nextNonWhitespace(boolean throwOnEof) throws IOException {
/*
* This code uses ugly local variables 'p' and 'l' representing the 'pos'
* and 'limit' fields respectively. Using locals rather than fields saves
* a few field reads for each whitespace character in a pretty-printed
* document, resulting in a 5% speedup. We need to flush 'p' to its field
* before any (potentially indirect) call to fillBuffer() and reread both
* 'p' and 'l' after any (potentially indirect) call to the same method.
*/
int p = 0;
while (source.request(p + 1)) {
int c = buffer.getByte(p++);
if (c == '\n' || c == ' ' || c == '\r' || c == '\t') {
continue;
}
buffer.skip(p - 1);
if (c == '/') {
if (!source.request(2)) {
return c;
}
checkLenient();
byte peek = buffer.getByte(1);
switch (peek) {
case '*':
// skip a /* c-style comment */
buffer.readByte(); // '/'
buffer.readByte(); // '*'
if (!skipTo("*/")) {
throw syntaxError("Unterminated comment");
}
buffer.readByte(); // '*'
buffer.readByte(); // '/'
p = 0;
continue;
case '/':
// skip a // end-of-line comment
buffer.readByte(); // '/'
buffer.readByte(); // '/'
skipToEndOfLine();
p = 0;
continue;
default:
return c;
}
} else if (c == '#') {
// Skip a # hash end-of-line comment. The JSON RFC doesn't specify this behaviour, but it's
// required to parse existing documents.
checkLenient();
skipToEndOfLine();
p = 0;
} else {
return c;
}
}
if (throwOnEof) {
throw new EOFException("End of input");
} else {
return -1;
}
}
private void checkLenient() throws IOException {
if (!lenient) {
throw syntaxError("Use JsonReader.setLenient(true) to accept malformed JSON");
}
}
/**
* Advances the position until after the next newline character. If the line
* is terminated by "\r\n", the '\n' must be consumed as whitespace by the
* caller.
*/
private void skipToEndOfLine() throws IOException {
long index = source.indexOfElement(LINEFEED_OR_CARRIAGE_RETURN);
buffer.skip(index != -1 ? index + 1 : buffer.size());
}
/**
* @param toFind a string to search for. Must not contain a newline.
*/
private boolean skipTo(String toFind) throws IOException {
outer:
for (; source.request(toFind.length());) {
for (int c = 0; c < toFind.length(); c++) {
if (buffer.getByte(c) != toFind.charAt(c)) {
buffer.readByte();
continue outer;
}
}
return true;
}
return false;
}
@Override public String toString() {
return "JsonReader(" + source + ")";
}
@Override public String getPath() {
return JsonScope.getPath(stackSize, stack, pathNames, pathIndices);
}
/**
* Unescapes the character identified by the character or characters that immediately follow a
* backslash. The backslash '\' should have already been read. This supports both unicode escapes
* "u000A" and two-character escapes "\n".
*
* @throws IOException if any unicode escape sequences are malformed.
*/
private char readEscapeCharacter() throws IOException {
if (!source.request(1)) {
throw syntaxError("Unterminated escape sequence");
}
byte escaped = buffer.readByte();
switch (escaped) {
case 'u':
if (!source.request(4)) {
throw new EOFException("Unterminated escape sequence at path " + getPath());
}
// Equivalent to Integer.parseInt(stringPool.get(buffer, pos, 4), 16);
char result = 0;
for (int i = 0, end = i + 4; i < end; i++) {
byte c = buffer.getByte(i);
result <<= 4;
if (c >= '0' && c <= '9') {
result += (c - '0');
} else if (c >= 'a' && c <= 'f') {
result += (c - 'a' + 10);
} else if (c >= 'A' && c <= 'F') {
result += (c - 'A' + 10);
} else {
throw syntaxError("\\u" + buffer.readUtf8(4));
}
}
buffer.skip(4);
return result;
case 't':
return '\t';
case 'b':
return '\b';
case 'n':
return '\n';
case 'r':
return '\r';
case 'f':
return '\f';
case '\n':
case '\'':
case '"':
case '\\':
case '/':
return (char) escaped;
default:
if (!lenient) throw syntaxError("Invalid escape sequence: \\" + (char) escaped);
return (char) escaped;
}
}
/**
* Throws a new IO exception with the given message and a context snippet
* with this reader's content.
*/
private JsonEncodingException syntaxError(String message) throws JsonEncodingException {
throw new JsonEncodingException(message + " at path " + getPath());
}
@Override void promoteNameToValue() throws IOException {
if (hasNext()) {
peekedString = nextName();
peeked = PEEKED_BUFFERED;
}
}
}