cn.wjybxx.dson.text.StringCharStream Maven / Gradle / Ivy
/*
* Copyright 2023-2024 wjybxx([email protected])
*
* 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 cn.wjybxx.dson.text;
import java.util.Objects;
/**
* 基于完整的字符串解析
*
* @author wjybxx
* date - 2023/6/5
*/
final class StringCharStream extends AbstractCharStream {
private CharSequence buffer;
public StringCharStream(CharSequence buffer) {
this.buffer = Objects.requireNonNull(buffer);
}
@Override
public void close() {
buffer = null;
}
@Override
protected boolean isClosed() {
return buffer == null;
}
@Override
protected int charAt(LineInfo curLine, int position) {
return buffer.charAt(position);
}
@Override
protected void checkUnreadOverFlow(int position) {
if (position < 0 || position >= buffer.length()) {
throw bufferOverFlow(position);
}
}
@Override
protected void scanMoreChars(LineInfo line) {
}
@Override
protected boolean scanNextLine() {
CharSequence buffer = this.buffer;
int bufferLength = buffer.length();
LineInfo curLine = getCurLine();
final int startPos;
final int ln;
if (curLine == null) {
ln = getFirstLn();
startPos = 0;
} else {
ln = curLine.ln + 1;
startPos = curLine.endPos + 1;
}
if (startPos >= bufferLength) {
return false;
}
int state = LineInfo.STATE_SCAN;
int endPos = startPos;
int headPos = -1;
for (; endPos < bufferLength; endPos++) {
char c = buffer.charAt(endPos);
// 需要放在switch-case之前，否则可能漏掉\r的非法head
if (headPos == -1 && !DsonTexts.isIndentChar(c)) {
headPos = endPos;
}
if (c == '\n') {
state = LineInfo.STATE_LF;
break;
}
if (c == '\r') {
if (endPos == bufferLength - 1) { // eof
state = LineInfo.STATE_EOF;
break;
}
c = buffer.charAt(++endPos);
if (c == '\n') { // CR LF
state = LineInfo.STATE_CRLF;
break;
}
}
if (endPos == bufferLength - 1) { // eof
state = LineInfo.STATE_EOF;
break;
}
}
LineInfo tempLine = new LineInfo(ln, startPos, endPos);
tempLine.state = state;
addLine(tempLine);
return true;
}
}