de.intarsys.pdf.cos.COSString Maven / Gradle / Ivy
/*
* Copyright (c) 2007, intarsys consulting GmbH
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
*
* - Redistributions of source code must retain the above copyright notice,
* this list of conditions and the following disclaimer.
*
* - Redistributions in binary form must reproduce the above copyright notice,
* this list of conditions and the following disclaimer in the documentation
* and/or other materials provided with the distribution.
*
* - Neither the name of intarsys nor the names of its contributors may be used
* to endorse or promote products derived from this software without specific
* prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
* LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*/
package de.intarsys.pdf.cos;
import java.io.UnsupportedEncodingException;
import java.nio.charset.Charset;
import java.util.Arrays;
import de.intarsys.pdf.encoding.PDFDocEncoding;
import de.intarsys.tools.hex.HexTools;
/**
* The string representation for a pdf document
*
*/
public class COSString extends COSPrimitiveObject implements Comparable {
private static String LINE_SEPARATOR = System.getProperty("line.separator"); //$NON-NLS-1$
/**
* Create a {@link COSString} from bytes.
*
* @param bytes
* @return The new {@link COSString}
*/
public static COSString create(byte[] bytes) {
if (bytes == null) {
throw new NullPointerException("COSString value can't be null"); //$NON-NLS-1$
}
return new COSString(bytes, null);
}
/**
* Create a {@link COSString} from bytes.
*
* @param bytes
* @return The new {@link COSString}
*/
public static COSString create(byte[] bytes, String encoding) {
if (bytes == null) {
throw new NullPointerException("COSString value can't be null"); //$NON-NLS-1$
}
return new COSString(bytes, encoding);
}
/**
* Create a {@link COSString} from string.
*
* @param string
* @return The new {@link COSString}
*/
public static COSString create(String string) {
if (string == null) {
throw new NullPointerException("COSString value can't be null"); //$NON-NLS-1$
}
if (PDFDocEncoding.UNIQUE.isEncodable(string)) {
return new COSString(string, null);
} else {
return new COSString(string, "UTF-16BE");
}
}
/**
* Create a {@link COSString} from string.
*
* @param string
* @return The new {@link COSString}
*/
public static COSString create(String string, String encoding) {
if (string == null) {
throw new NullPointerException("COSString value can't be null"); //$NON-NLS-1$
}
return new COSString(string, encoding);
}
/**
* Create a {@link COSString} from bytes in hex representation.
*
* @param bytes
* @return The new {@link COSString}
*/
public static COSString createHex(byte[] bytes) {
if (bytes == null) {
throw new NullPointerException("COSString value can't be null"); //$NON-NLS-1$
}
COSString result = new COSString(bytes, null);
result.setHexMode(true);
return result;
}
/**
* Create a {@link COSString} from bytes in hex representation.
*
* @param bytes
* @return The new {@link COSString}
*/
public static COSString createHex(byte[] bytes, String encoding) {
if (bytes == null) {
throw new NullPointerException("COSString value can't be null"); //$NON-NLS-1$
}
COSString result = new COSString(bytes, encoding);
result.setHexMode(true);
return result;
}
/**
* Create a {@link COSString} from string in hex
* representation.
*
* @param string
* @return The new {@link COSString}
*/
public static COSString createHex(String string) {
if (string == null) {
throw new NullPointerException("COSString value can't be null"); //$NON-NLS-1$
}
if (PDFDocEncoding.UNIQUE.isEncodable(string)) {
COSString result = new COSString(string, null);
result.setHexMode(true);
return result;
} else {
COSString result = new COSString(string, "UTF-16BE");
result.setHexMode(true);
return result;
}
}
/**
* Create a {@link COSString} from string in hex
* representation.
*
* @param string
* @return The new {@link COSString}
*/
public static COSString createHex(String string, String encoding) {
if (string == null) {
throw new NullPointerException("COSString value can't be null"); //$NON-NLS-1$
}
COSString result = new COSString(string, encoding);
result.setHexMode(true);
return result;
}
/**
* Create a {@link COSString} from string, escaping all
* newlines.
*
* @param string
* @return The new {@link COSString}
*/
public static COSString createMultiLine(String string) {
return create(toPDFString(string));
}
public static String toJavaString(String value) {
StringBuilder result = new StringBuilder();
int length = value.length();
boolean crFound = false;
for (int i = 0; i < length; i++) {
char c = value.charAt(i);
if (c == '\r') {
if (crFound) {
result.append(LINE_SEPARATOR);
}
crFound = true;
} else if (c == '\n') {
result.append(LINE_SEPARATOR);
crFound = false;
} else {
if (crFound) {
result.append(LINE_SEPARATOR);
}
result.append(c);
crFound = false;
}
}
if (crFound) {
result.append(LINE_SEPARATOR);
}
return result.toString();
}
public static String toPDFString(String value) {
// transform line delimiter (CR, CR/LN, LN) to CR
StringBuilder result = new StringBuilder();
int length = value.length();
boolean ignoreLn = false;
for (int i = 0; i < length; i++) {
char c = value.charAt(i);
if (c == '\n') {
if (!ignoreLn) {
result.append('\r');
}
} else {
result.append(c);
}
ignoreLn = c == '\r';
}
return result.toString();
}
private String encoding;
// the bytes that make up the string
private byte[] bytes;
// cached hash code
private int hash = 0;
// flag if this string has to be written in hex representation
private boolean hexMode = false;
private byte offset = 0;
// the decoded string representation of the bytes (lazy)
private String string;
protected COSString() {
super();
}
protected COSString(byte[] bytes, String encoding) {
super();
this.bytes = bytes;
this.encoding = encoding;
}
protected COSString(String string, String encoding) {
super();
this.string = string;
this.encoding = encoding;
}
/*
* (non-Javadoc)
*
* @see
* de.intarsys.pdf.cos.COSObject#accept(de.intarsys.pdf.cos.ICOSObjectVisitor
* )
*/
@Override
public java.lang.Object accept(ICOSObjectVisitor visitor)
throws COSVisitorException {
return visitor.visitFromString(this);
}
/*
* (non-Javadoc)
*
* @see de.intarsys.pdf.cos.COSObject#asString()
*/
@Override
public COSString asString() {
return this;
}
/*
* (non-Javadoc)
*
* @see de.intarsys.pdf.cos.COSObject#basicToString()
*/
@Override
protected String basicToString() {
if (isHexMode()) {
return "<" + hexStringValue() + ">"; //$NON-NLS-1$ //$NON-NLS-2$
} else {
return "(" + stringValue() + ")"; //$NON-NLS-1$ //$NON-NLS-2$
}
}
/**
* The bytes that make up this string.
*
* @return The bytes that make up this string.
*/
public byte[] byteValue() {
if (bytes == null) {
bytes = encode();
}
return bytes;
}
/**
* Reset the bytes for this {@link COSString}. You may need this if the
* encoding is changed during the {@link COSString} lifetime.
*/
public void clearBytes() {
if (bytes == null) {
return;
}
decode();
bytes = null;
}
/**
* Reset the string value for this {@link COSString}. You may need this if
* the encoding is changed during the {@link COSString} lifetime.
*/
public void clearString() {
if (string == null) {
return;
}
encode();
string = null;
}
/*
* (non-Javadoc)
*
* @see java.lang.Comparable#compareTo(java.lang.Object)
*/
public int compareTo(Object o) {
if (!(o instanceof COSString)) {
throw new ClassCastException("must compare with a COSString"); //$NON-NLS-1$
}
byte[] thisBytes = byteValue();
byte[] otherBytes = ((COSString) o).byteValue();
for (int i = 0; (i < thisBytes.length) && (i < otherBytes.length); i++) {
if (thisBytes[i] < otherBytes[i]) {
return -1;
}
if (thisBytes[i] > otherBytes[i]) {
return 1;
}
}
if (thisBytes.length < otherBytes.length) {
return -1;
}
if (thisBytes.length > otherBytes.length) {
return 1;
}
return 0;
}
/*
* (non-Javadoc)
*
* @see de.intarsys.pdf.cos.COSObject#copyBasic()
*/
@Override
protected COSObject copyBasic() {
COSString result = new COSString();
result.bytes = this.bytes;
result.hash = this.hash;
result.hexMode = this.hexMode;
result.string = this.string;
result.encoding = this.encoding;
result.offset = this.offset;
return result;
}
/**
* decode the string from the byte value in the given encoding
*
* @return the decoded string
*/
protected String decode() {
// test for well known internal encodings
testBuiltinEncoding();
if (encoding != null) {
try {
return new String(bytes, offset, bytes.length - offset,
encoding);
} catch (UnsupportedEncodingException e) {
return PDFDocEncoding.UNIQUE.decode(bytes);
}
}
return PDFDocEncoding.UNIQUE.decode(bytes);
}
/**
* encode the string in byte representation using the correct encoding
*
* @return the encoded string
*/
protected byte[] encode() {
if (encoding != null) {
if ("UTF-16BE".equals(encoding)) {
byte[] tempBytes;
try {
tempBytes = string.getBytes("UTF-16BE"); //$NON-NLS-1$
} catch (UnsupportedEncodingException e) {
// strange... :-)
return PDFDocEncoding.UNIQUE.encode(string);
}
byte[] resultBytes = new byte[tempBytes.length + 2];
resultBytes[0] = (byte) 0xfe;
resultBytes[1] = (byte) 0xff;
System.arraycopy(tempBytes, 0, resultBytes, 2, tempBytes.length);
return resultBytes;
} else if ("UTF-16LE".equals(encoding)) {
byte[] tempBytes;
try {
tempBytes = string.getBytes("UTF-16LE"); //$NON-NLS-1$
} catch (UnsupportedEncodingException e) {
// strange... :-)
return PDFDocEncoding.UNIQUE.encode(string);
}
byte[] resultBytes = new byte[tempBytes.length + 2];
resultBytes[0] = (byte) 0xff;
resultBytes[1] = (byte) 0xfe;
System.arraycopy(tempBytes, 0, resultBytes, 2, tempBytes.length);
return resultBytes;
} else {
try {
return string.getBytes(encoding);
} catch (UnsupportedEncodingException e) {
return PDFDocEncoding.UNIQUE.encode(string);
}
}
}
return PDFDocEncoding.UNIQUE.encode(string);
}
/*
* (non-Javadoc)
*
* @see java.lang.Object#equals(java.lang.Object)
*/
@Override
public boolean equals(Object o) {
if (!(o instanceof COSString)) {
return false;
}
return Arrays.equals(byteValue(), ((COSString) o).byteValue());
}
/**
* Lookup the custom encoding used by this string. This method returns null
* if the default PDF conventions are used.
*
* Be warned: If you use a custom encoding, there is no way for standard PDF
* tools to recover this information!
*
* @return Lookup the custom encoding used by this string
*/
public String getEncoding() {
return encoding;
}
/*
* (non-Javadoc)
*
* @see java.lang.Object#hashCode()
*/
@Override
public int hashCode() {
if (bytes == null) {
return super.hashCode();
}
int h = hash;
if (h == 0) {
for (int i = 0; i < bytes.length; i++) {
h = (31 * h) + bytes[i];
}
hash = h;
}
return h;
}
/**
* Show a hex encoded representation of the strings content.
*
* @return Show a hex encoded representation of the strings content.
*/
public String hexStringValue() {
return HexTools.bytesToHexString(byteValue());
}
/**
* true if this string has to be saved as hex representation
*
* @return true if this string has to be saved as hex
* representation
*/
public boolean isHexMode() {
return hexMode;
}
/**
* A Java {@link String} with correctly expanded newlines.
*
* @return A Java {@link String} with correctly expanded newlines.
*/
public String multiLineStringValue() {
return toJavaString(stringValue());
}
/*
* (non-Javadoc)
*
* @see de.intarsys.pdf.cos.COSObject#restoreState(java.lang.Object)
*/
@Override
public void restoreState(Object object) {
super.restoreState(object);
COSString cosString = (COSString) object;
this.bytes = cosString.bytes;
this.hash = cosString.hash;
this.hexMode = cosString.hexMode;
this.string = cosString.string;
}
/*
* (non-Javadoc)
*
* @see de.intarsys.tools.objectsession.ISaveStateSupport#saveState()
*/
public Object saveState() {
COSString result = new COSString();
result.bytes = this.bytes;
result.hash = this.hash;
result.hexMode = this.hexMode;
result.string = this.string;
result.encoding = this.encoding;
result.offset = this.offset;
result.container = this.container.saveStateContainer();
return result;
}
/**
* Set the {@link Charset} name to be used when decoding the
* {@link COSString} bytes. If no encoding is present, the default PDF
* conventions are used.
*
* Be warned: If you use a custom encoding, there is no way for standard PDF
* tools to recover this information!
*
* @param encoding
*/
public void setEncoding(String encoding) {
this.encoding = encoding;
}
/**
* Set the flag if this is written in hex representation
*
* @param newHexMode
* true if this is written in hex representation
*/
public void setHexMode(boolean newHexMode) {
hexMode = newHexMode;
}
/**
* The Java {@link String} representation of the receiver
*
* @return The Java {@link String} representation of the receiver
*/
@Override
public String stringValue() {
if (string == null) {
string = decode();
}
return string;
}
protected void testBuiltinEncoding() {
if (bytes.length < 2) {
return;
}
if ((bytes[0] == (byte) 0xfe) && (bytes[1] == (byte) 0xff)) {
offset = 2;
encoding = "UTF-16BE"; //$NON-NLS-1$
} else if ((bytes[0] == (byte) 0xff) && (bytes[1] == (byte) 0xfe)) {
// extend test to undocumented format used by some tools
offset = 2;
encoding = "UTF-16LE"; //$NON-NLS-1$
}
}
}