// Utils - assorted static utility routines
//
// Copyright (C)1996,1998 by Jef Poskanzer <jef@acme.com>. All rights reserved.
//
// Redistribution and use in source and binary forms, with or without
// modification, are permitted provided that the following conditions
// are met:
// 1. Redistributions of source code must retain the above copyright
// notice, this list of conditions and the following disclaimer.
// 2. 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.
//
// THIS SOFTWARE IS PROVIDED BY THE AUTHOR 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 AUTHOR 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.
//
// Visit the ACME Labs Java page for up-to-date versions of this and other
// fine Java utilities: http://www.acme.com/java/
package Acme;
import java.util.*;
import java.io.*;
import java.net.*;
import java.text.SimpleDateFormat;
/// Assorted static utility routines.
// <P>
// Whenever I come up with a static routine that might be of general use,
// I put it here. So far the class includes:
// <UL>
// <LI> some string routines that were left out of java.lang.String
// <LI> a general array-to-string routine
// <LI> a fixed version of java.io.InputStream's byte-array read routine
// <LI> a bunch of URL-hacking routines
// <LI> some easy-to-use wrappers for Runtime.exec
// <LI> a debugging routine to dump the current call stack
// <LI> a URLDecoder to match java.net.URLEncoder
// </UL>
// and lots more.
// <P>
// <A HREF="/resources/classes/Acme/Utils.java">Fetch the software.</A><BR>
// <A HREF="/resources/classes/Acme.tar.Z">Fetch the entire Acme package.</A>
public class Utils
{
/// Returns a date string formatted in Unix ls style - if it's within
// six months of now, Mmm dd hh:ss, else Mmm dd yyyy.
static final SimpleDateFormat shortfmt = new SimpleDateFormat("MMM dd HH:mm");
static final SimpleDateFormat longfmt = new SimpleDateFormat("MMM dd yyyy");
public static String lsDateStr( Date date )
{
if ( Math.abs( System.currentTimeMillis() - date.getTime() ) < 183L * 24L * 60L * 60L * 1000L )
return shortfmt.format(date);
else
return longfmt.format(date);
}
/// Returns "s" for numbers other than one, and "" for one.
public static String pluralStr( long n )
{
if ( n == 1 )
return "";
else
return "s";
}
// Various interval constants. Some are only approximate.
public static final long INT_SECOND = 1000L;
public static final long INT_MINUTE = INT_SECOND * 60L;
public static final long INT_HOUR = INT_MINUTE * 60L;
public static final long INT_DAY = INT_HOUR * 24L;
public static final long INT_WEEK = INT_DAY * 7L;
public static final long INT_MONTH = INT_DAY * 30L;
public static final long INT_YEAR = INT_DAY * 365L;
public static final long INT_DECADE = INT_DAY * 3652L;
/// Returns a string approximately describing a given time interval.
// @param interval the interval, in milliseconds
public static String intervalStr( long interval )
{
long decades, years, months, weeks, days, hours, minutes, seconds, millis;
decades = interval / INT_DECADE;
interval -= decades * INT_DECADE;
years = interval / INT_YEAR;
interval -= years * INT_YEAR;
months = interval / INT_MONTH;
interval -= months * INT_MONTH;
weeks = interval / INT_WEEK;
interval -= weeks * INT_WEEK;
days = interval / INT_DAY;
interval -= days * INT_DAY;
hours = interval / INT_HOUR;
interval -= hours * INT_HOUR;
minutes = interval / INT_MINUTE;
interval -= minutes * INT_MINUTE;
seconds = interval / INT_SECOND;
interval -= seconds * INT_SECOND;
millis = interval;
if ( decades > 0 )
if ( years == 0 )
return decades + " decade" + pluralStr( decades );
else
return
decades + " decade" + pluralStr( decades ) + ", " +
years + " years" + pluralStr( years );
else if ( years > 0 )
if ( months == 0 )
return years + " year" + pluralStr( years );
else
return
years + " year" + pluralStr( years ) + ", " +
months + " month" + pluralStr( months );
else if ( months > 0 )
if ( weeks == 0 )
return months + " month" + pluralStr( months );
else
return
months + " month" + pluralStr( months ) + ", " +
weeks + " week" + pluralStr( weeks );
else if ( weeks > 0 )
if ( days == 0 )
return weeks + " week" + pluralStr( weeks );
else
return
weeks + " week" + pluralStr( weeks ) + ", " +
days + " day" + pluralStr( days );
else if ( days > 0 )
if ( hours == 0 )
return days + " day" + pluralStr( days );
else
return
days + " day" + pluralStr( days ) + ", " +
hours + " hour" + pluralStr( hours );
else if ( hours > 0 )
if ( minutes == 0 )
return hours + " hour" + pluralStr( hours );
else
return
hours + " hour" + pluralStr( hours ) + ", " +
minutes + " minute" + pluralStr( minutes );
else if ( minutes > 0 )
if ( seconds == 0 )
return minutes + " minute" + pluralStr( minutes );
else
return
minutes + " minute" + pluralStr( minutes ) + ", " +
seconds + " second" + pluralStr( seconds );
else if ( seconds > 0 )
if ( millis == 0 )
return seconds + " second" + pluralStr( seconds );
else
return
seconds + " second" + pluralStr( seconds ) + ", " +
millis + " millisecond" + pluralStr( millis );
else
return millis + " millisecond" + pluralStr( millis );
}
/// Returns the length of the initial segment of str which consists
// entirely of characters from charSet.
public static int strSpan( String str, String charSet )
{
return strSpan( str, charSet, 0 );
}
/// Returns the length of the initial segment of str which consists
// entirely of characters from charSet, starting at the given index.
public static int strSpan( String str, String charSet, int fromIdx )
{
int i;
for ( i = fromIdx; i < str.length(); ++i )
if ( charSet.indexOf( str.charAt( i ) ) == -1 )
break;
return i - fromIdx;
}
/// Returns the length of the initial segment of str which consists
// entirely of characters NOT from charSet.
public static int strCSpan( String str, String charSet )
{
return strCSpan( str, charSet, 0 );
}
/// Returns the length of the initial segment of str which consists
// entirely of characters NOT from charSet, starting at the given index.
public static int strCSpan( String str, String charSet, int fromIdx )
{
int i;
for ( i = fromIdx; i < str.length(); ++i )
if ( charSet.indexOf( str.charAt( i ) ) != -1 )
break;
return i - fromIdx;
}
/// Checks whether a string matches a given wildcard pattern.
// Only does ? and *, and multiple patterns separated by |.
public static boolean match( String pattern, String string )
{
for ( int p = 0; ; ++p )
{
for ( int s = 0; ; ++p, ++s )
{
boolean sEnd = ( s >= string.length() );
boolean pEnd = ( p >= pattern.length() ||
pattern.charAt( p ) == '|' );
if ( sEnd && pEnd )
return true;
if ( sEnd || pEnd )
break;
if ( pattern.charAt( p ) == '?' )
continue;
if ( pattern.charAt( p ) == '*' )
{
int i;
++p;
for ( i = string.length(); i >= s; --i )
if ( match(
pattern.substring( p ),
string.substring( i ) ) ) /* not quite right */
return true;
break;
}
if ( pattern.charAt( p ) != string.charAt( s ) )
break;
}
p = pattern.indexOf( '|', p );
if ( p == -1 )
return false;
}
}
/// Finds the maximum length of a string that matches a given wildcard
// pattern. Only does ? and *, and multiple patterns separated by |.
public static int matchSpan( String pattern, String string )
{
int result = 0;
StringTokenizer st = new StringTokenizer(pattern, "|");
while (st.hasMoreTokens())
{
int len = matchSpan1(st.nextToken(), string);
if (len > result)
result = len;
}
return result;
}
static int matchSpan1( String pattern, String string )
{
int p=0;
for (; p < string.length() && p < pattern.length(); p++)
{
if (pattern.charAt(p) == string.charAt(p))
continue;
if (pattern.charAt(p) == '*')
return p-1;
return 0;
}
return p<(pattern.length()-1)?-1:p;
}
/// Returns the length of the initial segment of str1 that equals str2.
public static int sameSpan( String str1, String str2 )
{
int i;
for ( i = 0;
i < str1.length() && i < str2.length() &&
str1.charAt( i ) == str2.charAt( i );
++i )
;
return i;
}
/// Returns the number of times the given character appears in the string.
public static int charCount( String str, char c )
{
int n = 0;
for ( int i = 0; i < str.length(); ++i )
if ( str.charAt( i ) == c )
++n;
return n;
}
/// Turns a String into an array of Strings, by using StringTokenizer
// to split it up at whitespace.
public static String[] splitStr( String str )
{
StringTokenizer st = new StringTokenizer( str );
int n = st.countTokens();
String[] strs = new String[n];
for ( int i = 0; i < n; ++i )
strs[i] = st.nextToken();
return strs;
}
/// Turns a String into an array of Strings, by splitting it at
// the specified character. This does not use StringTokenizer,
// and therefore can handle empty fields.
public static String[] splitStr( String str, char delim )
{
int n = 1;
int index = -1;
while ( true )
{
index = str.indexOf( delim, index + 1 );
if ( index == -1 )
break;
++n;
}
String[] strs = new String[n];
index = -1;
for ( int i = 0; i < n - 1; ++i )
{
int nextIndex = str.indexOf( delim, index + 1 );
strs[i] = str.substring( index + 1, nextIndex );
index = nextIndex;
}
strs[n - 1] = str.substring( index + 1 );
return strs;
}
/// Turns an array of Strings into a single String, with the components
// separated by spaces.
public static String flattenStrarr( String[] strs )
{
StringBuffer sb = new StringBuffer();
for ( int i = 0; i < strs.length; ++i )
{
if ( i > 0 )
sb.append( ' ' );
sb.append( strs[i] );
}
return sb.toString();
}
/// Sorts an array of Strings.
// Java currently has no general sort function. Sorting Strings is
// common enough that it's worth making a special case.
public static void sortStrings( String[] strings )
{
// Just does a bubblesort.
for ( int i = 0; i < strings.length - 1; ++i )
{
for ( int j = i + 1; j < strings.length; ++j )
{
if ( strings[i].compareTo( strings[j] ) > 0 )
{
String t = strings[i];
strings[i] = strings[j];
strings[j] = t;
}
}
}
}
/// Locates a String in an array of Strings.
// Returns -1 if the String is not found.
public static int indexOfString( String[] strings, String string )
{
for ( int i = 0; i < strings.length; ++i )
if ( string.equals( strings[i] ) )
return i;
return -1;
}
/// Locates a String in an array of Strings, ignoring case.
// Returns -1 if the String is not found.
public static int indexOfStringIgnoreCase( String[] strings, String string )
{
for ( int i = 0; i < strings.length; ++i )
if ( string.equalsIgnoreCase( strings[i] ) )
return i;
return -1;
}
/// Compares two arrays of Strings for equality.
public static boolean equalsStrings( String[] strings1, String[] strings2 )
{
if ( strings1.length != strings2.length )
return false;
for ( int i = 0; i < strings1.length; ++i )
if ( ! strings1[i].equals( strings2[i] ) )
return false;
return true;
}
/// Returns the number a raised to the power of b. Long version
// of Math.pow(). Throws ArithmeticException if b is negative.
public static long pow( long a, long b ) throws ArithmeticException
{
if ( b < 0 )
throw new ArithmeticException();
long r = 1;
while ( b != 0 )
{
if ( odd( b ) )
r *= a;
b >>>= 1;
a *= a;
}
return r;
}
/// Parse an integer, returning a default value on errors.
public static int parseInt( String str, int def )
{
try
{
return Integer.parseInt( str );
}
catch ( Exception e )
{
return def;
}
}
/// Parse a long, returning a default value on errors.
public static long parseLong( String str, long def )
{
try
{
return Long.parseLong( str );
}
catch ( Exception e )
{
return def;
}
}
/// An array-to-String routine. Handles arrays of arbitrary
// type, including nested arrays. Sample output:
// <BLOCKQUOTE><CODE><PRE>
// byte[]: { (byte)0, (byte)1, (byte)2 }
// char[]: { '0', '1', '2' }
// short[]: { (short)0, (short)1, (short)2 }
// int[]: { 0, 1, 2 }
// long[]: { 0L, 1L, 2L }
// float[]: { 0F, 1F, 2F }
// double[]: { 0D, 1D, 2D }
// String[]: { "0", "1", "2" }
// int[][]: { { 0, 1, 2 }, { 3, 4, 5 } }
// </PRE></CODE></BLOCKQUOTE>
public static String arrayToString( Object o )
{
if ( o == null )
return "null";
String cl = o.getClass().getName();
if ( ! cl.startsWith( "[" ) )
// It's not an array; just call its toString method.
return o.toString();
StringBuffer sb = new StringBuffer( "{ " );
if ( o instanceof byte[] )
{
byte[] ba = (byte[]) o;
for ( int i = 0; i < ba.length; ++i )
{
if ( i > 0 ) sb.append( ", " );
sb.append( "(byte)" );
sb.append( ba[i] );
}
}
else if ( o instanceof char[] )
{
char[] ca = (char[]) o;
for ( int i = 0; i < ca.length; ++i )
{
if ( i > 0 ) sb.append( ", " );
sb.append( "'" );
sb.append( ca[i] );
sb.append( "'" );
}
}
else if ( o instanceof short[] )
{
short[] sa = (short[]) o;
for ( int i = 0; i < sa.length; ++i )
{
if ( i > 0 ) sb.append( ", " );
sb.append( "(short)" );
sb.append( sa[i] );
}
}
else if ( o instanceof int[] )
{
int[] ia = (int[]) o;
for ( int i = 0; i < ia.length; ++i )
{
if ( i > 0 ) sb.append( ", " );
sb.append( ia[i] );
}
}
else if ( o instanceof long[] )
{
long[] la = (long[]) o;
for ( int i = 0; i < la.length; ++i )
{
if ( i > 0 ) sb.append( ", " );
sb.append( la[i] );
sb.append( "L" );
}
}
else if ( o instanceof float[] )
{
float[] fa = (float[]) o;
for ( int i = 0; i < fa.length; ++i )
{
if ( i > 0 ) sb.append( ", " );
sb.append( fa[i] );
sb.append( "F" );
}
}
else if ( o instanceof double[] )
{
double[] da = (double[]) o;
for ( int i = 0; i < da.length; ++i )
{
if ( i > 0 ) sb.append( ", " );
sb.append( da[i] );
sb.append( "D" );
}
}
else if ( o instanceof String )
{
// Special-case Strings so we can surround them with quotes.
String[] sa = (String[]) o;
for ( int i = 0; i < sa.length; ++i )
{
if ( i > 0 ) sb.append( ", " );
sb.append( "\"" );
sb.append( sa[i] );
sb.append( "\"" );
}
}
else if ( cl.startsWith( "[L" ) )
{
// Some random class.
Object[] oa = (Object[]) o;
for ( int i = 0; i < oa.length; ++i )
{
if ( i > 0 ) sb.append( ", " );
sb.append( oa[i] );
}
}
else if ( cl.startsWith( "[[" ) )
{
// Nested arrays.
Object[] aa = (Object[]) o;
for ( int i = 0; i < aa.length; ++i )
{
if ( i > 0 ) sb.append( ", " );
sb.append( arrayToString( aa[i] ) );
}
}
else
sb.append( "(unknown array type)" );
sb.append( " }" );
return sb.toString();
}
/// Check if an object extends a given class or one of its superclasses.
// An instanceof that works on Class objects at runtime, instead
// of type descriptors at compile time.
public static boolean instanceOf( Object o, Class cl )
{
// Null check.
if ( o == null || cl == null )
return false;
Class ocl = o.getClass();
// Check if they are the same class.
if ( ocl.equals( cl ) )
return true;
// If the class is not itself an interface, then check its interfaces.
if ( ! cl.isInterface() )
{
Class ifs[] = cl.getInterfaces();
for ( int i = 0; i < ifs.length; ++i )
if ( instanceOf( o, ifs[i] ) )
return true;
}
// And check supeclasses.
Class scl = cl.getSuperclass();
if ( scl != null )
if ( instanceOf( o, scl ) )
return true;
// Guess not.
return false;
}
/// Test is a number is even.
public static boolean even( long n )
{
return ( n & 1 ) == 0;
}
/// Test is a number is odd.
public static boolean odd( long n )
{
return ( n & 1 ) != 0;
}
/// Count the number of 1-bits in a byte.
public static int countOnes( byte n )
{
return countOnes( n & 0xffL );
}
/// Count the number of 1-bits in an int.
public static int countOnes( int n )
{
return countOnes( n & 0xffffffffL );
}
/// Count the number of 1-bits in a long.
public static int countOnes( long n )
{
// There are faster ways to do this, all the way up to looking
// up bytes in a 256-element table. But this is not too bad.
int count = 0;
while ( n != 0 )
{
if ( odd( n ) )
++count;
n >>>= 1;
}
return count;
}
/// A fixed version of java.io.InputStream.read(byte[], int, int). The
// standard version catches and ignores IOExceptions from below.
// This version sends them on to the caller.
public static int read( InputStream in, byte[] b, int off, int len ) throws IOException
{
if ( len <= 0 )
return 0;
int c = in.read();
if ( c == -1 )
return -1;
if ( b != null )
b[off] = (byte) c;
int i;
for ( i = 1; i < len ; ++i )
{
c = in.read();
if ( c == -1 )
break;
if ( b != null )
b[off + i] = (byte) c;
}
return i;
}
/// A version of read that reads the entire requested block, instead
// of sometimes terminating early.
// @return -1 on EOF, otherwise len
public static int readFully( InputStream in, byte[] b, int off, int len ) throws IOException
{
int l, r;
for ( l = 0; l < len; )
{
r = read( in, b, l, len - l );
if ( r == -1 )
return -1;
l += r;
}
return len;
}
/// Make a URL with no ref part and no query string. Also, if it's
// a directory then make sure there's a trailing slash.
public static URL plainUrl( URL context, String urlStr ) throws MalformedURLException
{
URL url = new URL( context, urlStr );
String fileStr = url.getFile();
int i = fileStr.indexOf( '?' );
if ( i != -1 )
fileStr = fileStr.substring( 0, i );
url = new URL(
url.getProtocol(), url.getHost(), url.getPort(), fileStr );
if ( ( ! fileStr.endsWith( "/" ) ) &&
urlStrIsDir( url.toExternalForm() ) )
{
fileStr = fileStr + "/";
url = new URL(
url.getProtocol(), url.getHost(), url.getPort(), fileStr );
}
return url;
}
/// Make a URL with no ref part and no query string. Also, if it's
// a directory then make sure there's a trailing slash.
public static URL plainUrl( String urlStr ) throws MalformedURLException
{
return plainUrl( null, urlStr );
}
/// Figure out the base URL for a given URL. What this means is
// if the URL points to a directory, you get that directory; if the
// URL points to a file, you get the directory the file is in.
public static String baseUrlStr( String urlStr )
{
if ( urlStr.endsWith( "/" ) )
return urlStr;
if ( urlStrIsDir( urlStr ) )
return urlStr + "/";
return urlStr.substring( 0, urlStr.lastIndexOf( '/' ) + 1 );
}
/// Makes sure if a URL is a directory, it ends with a slash.
public static String fixDirUrlStr( String urlStr )
{
if ( urlStr.endsWith( "/" ) )
return urlStr;
if ( urlStrIsDir( urlStr ) )
return urlStr + "/";
return urlStr;
}
/// Figures out whether a URL points to a directory or not.
// Web servers are lenient and accept directory-URLs without
// the trailing slash. What they actually do is return a
// redirect to the same URL with the trailing slash appended.
// Unfortunately, Java doesn't let us see that such a redirect
// happened. Instead we have to figure out it's a directory
// indirectly and heuristically.
public static boolean urlStrIsDir( String urlStr )
{
// If it ends with a slash, it's probably a directory.
if ( urlStr.endsWith( "/" ) )
return true;
// If the last component has a dot, it's probably not a directory.
int lastSlash = urlStr.lastIndexOf( '/' );
int lastPeriod = urlStr.lastIndexOf( '.' );
if ( lastPeriod != -1 && ( lastSlash == -1 || lastPeriod > lastSlash ) )
return false;
// Otherwise, append a slash and try to connect. This is
// fairly expensive.
String urlStrWithSlash = urlStr + "/";
try
{
URL url = new URL( urlStrWithSlash );
InputStream f = url.openStream();
f.close();
// Worked fine - it's probably a directory.
return true;
}
catch ( Exception e )
{
// Got an error - must not be a directory.
return false;
}
}
// Figures out whether a URL is absolute or not.
public static boolean urlStrIsAbsolute( String urlStr )
{
if ( urlStr.startsWith( "/" ) || urlStr.indexOf( ":/" ) != -1 )
return true;
// Should handle :8000/ and such too.
return false;
}
// Returns an equivalent URL string that is guaranteed to be absolute.
public static String absoluteUrlStr( String urlStr, URL contextUrl ) throws MalformedURLException
{
URL url = new URL( contextUrl, urlStr );
return url.toExternalForm();
}
/// URLDecoder to go along with java.net.URLEncoder. Why there isn't
// already a decoder in the standard library is a mystery to me.
public static String urlDecoder( String encoded )
{
StringBuffer decoded = new StringBuffer();
int len = encoded.length();
for ( int i = 0; i < len; ++i )
{
if ( encoded.charAt( i ) == '%' && i + 2 < len )
{
int d1 = Character.digit( encoded.charAt( i + 1 ), 16 );
int d2 = Character.digit( encoded.charAt( i + 2 ), 16 );
if ( d1 != -1 && d2 != -1 )
decoded.append( (char) ( ( d1 << 4 ) + d2 ) );
i += 2;
}
else if ( encoded.charAt( i ) == '+' )
decoded.append( ' ' );
else
decoded.append( encoded.charAt( i ) );
}
return decoded.toString();
}
/// Check if an array contains a given element.
public static boolean arraycontains( Object[] array, Object element )
{
for ( int i = 0; i < array.length; ++i )
if ( array[i].equals( element ) )
return true;
return false;
}
/// Run a program on the host system.
// <P>
// This routine runs the specified command, waits for it to
// finish, and returns the exit status.
// This is like the Unix system() routine. Unlike the Unix version,
// though, stdout and stderr get thrown away unless you redirect them.
public static int system( String cmd )
{
try
{
return runCommand( cmd ).waitFor();
}
catch ( IOException e )
{
return -1;
}
catch ( InterruptedException e )
{
return -1;
}
}
/// Run a program on the host system, and capture the output.
// <P>
// This routine runs the specified command, and returns an InputStream
// for reading the output of the program.
// <P>
// <B>WARNING:</B> In JDK1.0.2 there is a serious bug in the process
// IO routines, such that reading all the way to the end of a process's
// output will invariably get you an IOException( "read error" ).
// In some cases you will also <B>lose</B> the last bufferload of
// the output. The workaround is to add a " ; sleep 1" to the end of
// your command, and to ignore the "read error" IOException.
public static InputStream popenr( String cmd )
{
try
{
return runCommand( cmd ).getInputStream();
}
catch ( IOException e )
{
return null;
}
}
/// Run a program on the host system, and send it some input.
// <P>
// This routine runs the specified command, and returns an OutputStream
// for writing the program's input.
public static OutputStream popenw( String cmd )
{
try
{
return runCommand( cmd ).getOutputStream();
}
catch ( IOException e )
{
return null;
}
}
/// Run a program on the host system.
// <P>
// This routine runs the specified command, and returns a Process
// object so you can do what you like with it.
// <P>
// <B>WARNING:</B> In JDK1.0.2 there is a serious bug in the process
// IO routines, such that reading all the way to the end of a process's
// output will invariably get you an IOException( "read error" ).
// In some cases you will also <B>lose</B> the last bufferload of
// the output. The workaround is to add a " ; sleep 1" to the end of
// your command, and to ignore the "read error" IOException.
public static Process runCommand( String cmd ) throws IOException
{
Runtime runtime = Runtime.getRuntime();
String[] shCmd = new String[3];
shCmd[0] = "/bin/sh";
shCmd[1] = "-c";
shCmd[2] = cmd;
return runtime.exec( shCmd );
}
/// Copy the input to the output until EOF.
public static void copyStream( InputStream in, OutputStream out ) throws IOException
{
byte[] buf = new byte[4096];
int len;
while ( ( len = in.read( buf ) ) != -1 )
out.write( buf, 0, len );
}
/// Copy the input to the output until EOF.
public static void copyStream( Reader in, Writer out ) throws IOException
{
char[] buf = new char[4096];
int len;
while ( ( len = in.read( buf ) ) != -1 )
out.write( buf, 0, len );
}
/// Copy the input to the output until EOF.
public static void copyStream( InputStream in, Writer out ) throws IOException
{
byte[] buf1 = new byte[4096];
char[] buf2 = new char[4096];
int len, i;
while ( ( len = in.read( buf1 ) ) != -1 )
{
for ( i = 0; i < len; ++i )
buf2[i] = (char) buf1[i];
out.write( buf2, 0, len );
}
}
/// Copy the input to the output until EOF.
public static void copyStream( Reader in, OutputStream out ) throws IOException
{
char[] buf1 = new char[4096];
byte[] buf2 = new byte[4096];
int len, i;
while ( ( len = in.read( buf1 ) ) != -1 )
{
for ( i = 0; i < len; ++i )
buf2[i] = (byte) buf1[i];
out.write( buf2, 0, len );
}
}
/// Dump out the current call stack.
public static void dumpStack( PrintStream p )
{
(new Throwable()).printStackTrace( p );
}
/// Dump out the current call stack onto System.err.
public static void dumpStack()
{
(new Throwable()).printStackTrace();
}
/// add a hash table to a hash table
public static void putAll(Hashtable _dest, Hashtable _src) {
}
}
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