org.h2.util.json.JSONStringSource Maven / Gradle / Ivy
/*
* Copyright 2004-2022 H2 Group. Multiple-Licensed under the MPL 2.0,
* and the EPL 1.0 (https://h2database.com/html/license.html).
* Initial Developer: H2 Group
*/
package org.h2.util.json;
import java.math.BigDecimal;
import org.h2.util.StringUtils;
/**
* JSON string source.
*/
public final class JSONStringSource extends JSONTextSource {
/**
* Parses source string to a specified target.
*
* @param string
* source
* @param target
* target
* @param
* the type of the result
* @return the result of the target
*/
public static R parse(String string, JSONTarget target) {
new JSONStringSource(string, target).parse();
return target.getResult();
}
/**
* Normalizes textual JSON representation.
*
* @param string
* source representation
* @return normalized representation
*/
public static byte[] normalize(String string) {
return parse(string, new JSONByteArrayTarget());
}
private final String string;
private final int length;
private int index;
JSONStringSource(String string, JSONTarget target) {
super(target);
this.string = string;
this.length = string.length();
if (length == 0) {
throw new IllegalArgumentException();
}
// Ignore BOM
if (string.charAt(index) == '\uFEFF') {
index++;
}
}
@Override
int nextCharAfterWhitespace() {
int index = this.index;
while (index < length) {
char ch = string.charAt(index++);
switch (ch) {
case '\t':
case '\n':
case '\r':
case ' ':
break;
default:
this.index = index;
return ch;
}
}
return -1;
}
@Override
void readKeyword1(String keyword) {
int l = keyword.length() - 1;
if (!string.regionMatches(index, keyword, 1, l)) {
throw new IllegalArgumentException();
}
index += l;
}
@Override
void parseNumber(boolean positive) {
int index = this.index;
int start = index - 1;
index = skipInt(index, positive);
l: if (index < length) {
char ch = string.charAt(index);
if (ch == '.') {
index = skipInt(index + 1, false);
if (index >= length) {
break l;
}
ch = string.charAt(index);
}
if (ch == 'E' || ch == 'e') {
if (++index >= length) {
throw new IllegalArgumentException();
}
ch = string.charAt(index);
if (ch == '+' || ch == '-') {
index++;
}
index = skipInt(index, false);
}
}
target.valueNumber(new BigDecimal(string.substring(start, index)));
this.index = index;
}
private int skipInt(int index, boolean hasInt) {
while (index < length) {
char ch = string.charAt(index);
if (ch >= '0' && ch <= '9') {
hasInt = true;
index++;
} else {
break;
}
}
if (!hasInt) {
throw new IllegalArgumentException();
}
return index;
}
@Override
int nextChar() {
if (index >= length) {
throw new IllegalArgumentException();
}
return string.charAt(index++);
}
@Override
char readHex() {
if (index + 3 >= length) {
throw new IllegalArgumentException();
}
try {
return (char) Integer.parseInt(string.substring(index, index += 4), 16);
} catch (NumberFormatException e) {
throw new IllegalArgumentException();
}
}
@Override
public String toString() {
return StringUtils.addAsterisk(string, index);
}
}