public void checkFdfHeader() throws IOException {
file.setStartOffset(0);
String str = readString(1024);
int idx = str.indexOf("%FDF-1.2");
if (idx < 0) throw new IOException("FDF header signature not found.");
file.setStartOffset(idx);
}
public char checkPdfHeader() throws IOException {
file.setStartOffset(0);
String str = readString(1024);
int idx = str.indexOf("%PDF-1.");
if (idx < 0) throw new IOException("PDF header signature not found.");
file.setStartOffset(idx);
return str.charAt(idx + 7);
}
public int getStartxref() throws IOException {
int size = Math.min(1024, file.length());
int pos = file.length() - size;
file.seek(pos);
String str = readString(1024);
int idx = str.lastIndexOf("startxref");
if (idx < 0) throw new IOException("PDF startxref not found.");
return pos + idx;
}
public void nextValidToken() throws IOException {
int level = 0;
String n1 = null;
String n2 = null;
int ptr = 0;
while (nextToken()) {
if (type == TK_COMMENT) continue;
switch (level) {
case 0:
{
if (type != TK_NUMBER) return;
ptr = file.getFilePointer();
n1 = stringValue;
++level;
break;
}
case 1:
{
if (type != TK_NUMBER) {
file.seek(ptr);
type = TK_NUMBER;
stringValue = n1;
return;
}
n2 = stringValue;
++level;
break;
}
default:
{
if (type != TK_OTHER || !stringValue.equals("R")) {
file.seek(ptr);
type = TK_NUMBER;
stringValue = n1;
return;
}
type = TK_REF;
reference = Integer.valueOf(n1).intValue();
generation = Integer.valueOf(n2).intValue();
return;
}
}
}
throwError("Unexpected end of file");
}
public String readString(int size) throws IOException {
StringBuffer buf = new StringBuffer();
int ch;
while ((size--) > 0) {
ch = file.read();
if (ch == -1) break;
buf.append((char) ch);
}
return buf.toString();
}
public boolean nextToken() throws IOException {
StringBuffer outBuf = null;
stringValue = EMPTY;
int ch = 0;
do {
ch = file.read();
} while (ch != -1 && isWhitespace(ch));
if (ch == -1) return false;
switch (ch) {
case '[':
type = TK_START_ARRAY;
break;
case ']':
type = TK_END_ARRAY;
break;
case '/':
{
outBuf = new StringBuffer();
type = TK_NAME;
while (true) {
ch = file.read();
if (delims[ch + 1]) break;
if (ch == '#') {
ch = (getHex(file.read()) << 4) + getHex(file.read());
}
outBuf.append((char) ch);
}
backOnePosition(ch);
break;
}
case '>':
ch = file.read();
if (ch != '>') throwError("'>' not expected");
type = TK_END_DIC;
break;
case '<':
{
int v1 = file.read();
if (v1 == '<') {
type = TK_START_DIC;
break;
}
outBuf = new StringBuffer();
type = TK_STRING;
hexString = true;
int v2 = 0;
while (true) {
while (isWhitespace(v1)) v1 = file.read();
if (v1 == '>') break;
v1 = getHex(v1);
if (v1 < 0) break;
v2 = file.read();
while (isWhitespace(v2)) v2 = file.read();
if (v2 == '>') {
ch = v1 << 4;
outBuf.append((char) ch);
break;
}
v2 = getHex(v2);
if (v2 < 0) break;
ch = (v1 << 4) + v2;
outBuf.append((char) ch);
v1 = file.read();
}
if (v1 < 0 || v2 < 0) throwError("Error reading string");
break;
}
case '%':
type = TK_COMMENT;
do {
ch = file.read();
} while (ch != -1 && ch != '\r' && ch != '\n');
break;
case '(':
{
outBuf = new StringBuffer();
type = TK_STRING;
hexString = false;
int nesting = 0;
while (true) {
ch = file.read();
if (ch == -1) break;
if (ch == '(') {
++nesting;
} else if (ch == ')') {
--nesting;
} else if (ch == '\\') {
boolean lineBreak = false;
ch = file.read();
switch (ch) {
case 'n':
ch = '\n';
break;
case 'r':
ch = '\r';
break;
case 't':
ch = '\t';
break;
case 'b':
ch = '\b';
break;
case 'f':
ch = '\f';
break;
case '(':
case ')':
case '\\':
break;
case '\r':
lineBreak = true;
ch = file.read();
if (ch != '\n') backOnePosition(ch);
break;
case '\n':
lineBreak = true;
break;
default:
{
if (ch < '0' || ch > '7') {
break;
}
int octal = ch - '0';
ch = file.read();
if (ch < '0' || ch > '7') {
backOnePosition(ch);
ch = octal;
break;
}
octal = (octal << 3) + ch - '0';
ch = file.read();
if (ch < '0' || ch > '7') {
backOnePosition(ch);
ch = octal;
break;
}
octal = (octal << 3) + ch - '0';
ch = octal & 0xff;
break;
}
}
if (lineBreak) continue;
if (ch < 0) break;
} else if (ch == '\r') {
ch = file.read();
if (ch < 0) break;
if (ch != '\n') {
backOnePosition(ch);
ch = '\n';
}
}
if (nesting == -1) break;
outBuf.append((char) ch);
}
if (ch == -1) throwError("Error reading string");
break;
}
default:
{
outBuf = new StringBuffer();
if (ch == '-' || ch == '+' || ch == '.' || (ch >= '0' && ch <= '9')) {
type = TK_NUMBER;
do {
outBuf.append((char) ch);
ch = file.read();
} while (ch != -1 && ((ch >= '0' && ch <= '9') || ch == '.'));
} else {
type = TK_OTHER;
do {
outBuf.append((char) ch);
ch = file.read();
} while (!delims[ch + 1]);
}
backOnePosition(ch);
break;
}
}
if (outBuf != null) stringValue = outBuf.toString();
return true;
}
public void throwError(String error) throws IOException {
throw new IOException(error + " at file pointer " + file.getFilePointer());
}
public void backOnePosition(int ch) throws IOException {
if (ch != -1) file.pushBack((byte) ch);
}
public int read() throws IOException {
return file.read();
}
public int length() throws IOException {
return file.length();
}
public void close() throws IOException {
file.close();
}
public int getFilePointer() throws IOException {
return file.getFilePointer();
}
public void seek(int pos) throws IOException {
file.seek(pos);
}
