org.bouncycastle.util.Strings Maven / Gradle / Ivy
package org.bouncycastle.util;
import java.io.ByteArrayOutputStream;
import java.io.IOException;
import java.io.OutputStream;
import java.security.AccessController;
import java.security.PrivilegedAction;
import java.util.ArrayList;
import java.util.Vector;
import org.bouncycastle.util.encoders.UTF8;
/**
* String utilities.
*/
public final class Strings
{
private static String LINE_SEPARATOR;
static
{
try
{
LINE_SEPARATOR = AccessController.doPrivileged(new PrivilegedAction()
{
public String run()
{
// the easy way
return System.getProperty("line.separator");
}
});
}
catch (Exception e)
{
try
{
// the harder way
LINE_SEPARATOR = String.format("%n");
}
catch (Exception ef)
{
LINE_SEPARATOR = "\n"; // we're desperate use this...
}
}
}
public static String fromUTF8ByteArray(byte[] bytes)
{
char[] chars = new char[bytes.length];
int len = UTF8.transcodeToUTF16(bytes, chars);
if (len < 0)
{
throw new IllegalArgumentException("Invalid UTF-8 input");
}
return new String(chars, 0, len);
}
public static byte[] toUTF8ByteArray(String string)
{
return toUTF8ByteArray(string.toCharArray());
}
public static byte[] toUTF8ByteArray(char[] string)
{
ByteArrayOutputStream bOut = new ByteArrayOutputStream();
try
{
toUTF8ByteArray(string, bOut);
}
catch (IOException e)
{
throw new IllegalStateException("cannot encode string to byte array!");
}
return bOut.toByteArray();
}
public static void toUTF8ByteArray(char[] string, OutputStream sOut)
throws IOException
{
char[] c = string;
int i = 0;
while (i < c.length)
{
char ch = c[i];
if (ch < 0x0080)
{
sOut.write(ch);
}
else if (ch < 0x0800)
{
sOut.write(0xc0 | (ch >> 6));
sOut.write(0x80 | (ch & 0x3f));
}
// surrogate pair
else if (ch >= 0xD800 && ch <= 0xDFFF)
{
// in error - can only happen, if the Java String class has a
// bug.
if (i + 1 >= c.length)
{
throw new IllegalStateException("invalid UTF-16 codepoint");
}
char W1 = ch;
ch = c[++i];
char W2 = ch;
// in error - can only happen, if the Java String class has a
// bug.
if (W1 > 0xDBFF)
{
throw new IllegalStateException("invalid UTF-16 codepoint");
}
int codePoint = (((W1 & 0x03FF) << 10) | (W2 & 0x03FF)) + 0x10000;
sOut.write(0xf0 | (codePoint >> 18));
sOut.write(0x80 | ((codePoint >> 12) & 0x3F));
sOut.write(0x80 | ((codePoint >> 6) & 0x3F));
sOut.write(0x80 | (codePoint & 0x3F));
}
else
{
sOut.write(0xe0 | (ch >> 12));
sOut.write(0x80 | ((ch >> 6) & 0x3F));
sOut.write(0x80 | (ch & 0x3F));
}
i++;
}
}
/**
* A locale independent version of toUpperCase.
*
* @param string input to be converted
* @return a US Ascii uppercase version
*/
public static String toUpperCase(String string)
{
boolean changed = false;
char[] chars = string.toCharArray();
for (int i = 0; i != chars.length; i++)
{
char ch = chars[i];
if ('a' <= ch && 'z' >= ch)
{
changed = true;
chars[i] = (char)(ch - 'a' + 'A');
}
}
if (changed)
{
return new String(chars);
}
return string;
}
/**
* A locale independent version of toLowerCase.
*
* @param string input to be converted
* @return a US ASCII lowercase version
*/
public static String toLowerCase(String string)
{
boolean changed = false;
char[] chars = string.toCharArray();
for (int i = 0; i != chars.length; i++)
{
char ch = chars[i];
if ('A' <= ch && 'Z' >= ch)
{
changed = true;
chars[i] = (char)(ch - 'A' + 'a');
}
}
if (changed)
{
return new String(chars);
}
return string;
}
public static byte[] toByteArray(char[] chars)
{
byte[] bytes = new byte[chars.length];
for (int i = 0; i != bytes.length; i++)
{
bytes[i] = (byte)chars[i];
}
return bytes;
}
public static byte[] toByteArray(String string)
{
byte[] bytes = new byte[string.length()];
for (int i = 0; i != bytes.length; i++)
{
char ch = string.charAt(i);
bytes[i] = (byte)ch;
}
return bytes;
}
public static int toByteArray(String s, byte[] buf, int off)
{
int count = s.length();
for (int i = 0; i < count; ++i)
{
char c = s.charAt(i);
buf[off + i] = (byte)c;
}
return count;
}
/**
* Constant time string comparison.
*
* @param a a string.
* @param b another string to compare to a.
*
* @return true if a and b represent the same string, false otherwise.
*/
public static boolean constantTimeAreEqual(String a, String b)
{
boolean isEqual = a.length() == b.length();
int len = a.length();
for (int i = 0; i != len; i++)
{
isEqual &= (a.charAt(i) == b.charAt(i));
}
return isEqual;
}
/**
* Convert an array of 8 bit characters into a string.
*
* @param bytes 8 bit characters.
* @return resulting String.
*/
public static String fromByteArray(byte[] bytes)
{
return new String(asCharArray(bytes));
}
/**
* Do a simple conversion of an array of 8 bit characters into a string.
*
* @param bytes 8 bit characters.
* @return resulting String.
*/
public static char[] asCharArray(byte[] bytes)
{
char[] chars = new char[bytes.length];
for (int i = 0; i != chars.length; i++)
{
chars[i] = (char)(bytes[i] & 0xff);
}
return chars;
}
public static String[] split(String input, char delimiter)
{
Vector v = new Vector();
boolean moreTokens = true;
String subString;
while (moreTokens)
{
int tokenLocation = input.indexOf(delimiter);
if (tokenLocation > 0)
{
subString = input.substring(0, tokenLocation);
v.addElement(subString);
input = input.substring(tokenLocation + 1);
}
else
{
moreTokens = false;
v.addElement(input);
}
}
String[] res = new String[v.size()];
for (int i = 0; i != res.length; i++)
{
res[i] = (String)v.elementAt(i);
}
return res;
}
public static StringList newList()
{
return new StringListImpl();
}
public static String lineSeparator()
{
return LINE_SEPARATOR;
}
private static class StringListImpl
extends ArrayList
implements StringList
{
public boolean add(String s)
{
return super.add(s);
}
public String set(int index, String element)
{
return super.set(index, element);
}
public void add(int index, String element)
{
super.add(index, element);
}
public String[] toStringArray()
{
String[] strs = new String[this.size()];
for (int i = 0; i != strs.length; i++)
{
strs[i] = this.get(i);
}
return strs;
}
public String[] toStringArray(int from, int to)
{
String[] strs = new String[to - from];
for (int i = from; i != this.size() && i != to; i++)
{
strs[i - from] = this.get(i);
}
return strs;
}
}
}