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Java 1.8+ Library with tons of utility classes required in all projects
/*
* Copyright (C) 2014-2022 Philip Helger (www.helger.com)
* philip[at]helger[dot]com
*
* 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 com.helger.commons.lang;
import java.io.File;
import java.io.IOException;
import java.io.InputStream;
import java.io.Reader;
import java.net.MalformedURLException;
import java.nio.charset.Charset;
import java.util.Map;
import java.util.Properties;
import java.util.function.Function;
import javax.annotation.Nonnull;
import javax.annotation.Nullable;
import javax.annotation.WillClose;
import javax.annotation.concurrent.Immutable;
import com.helger.commons.ValueEnforcer;
import com.helger.commons.annotation.ReturnsMutableCopy;
import com.helger.commons.collection.impl.CommonsHashMap;
import com.helger.commons.collection.impl.ICommonsMap;
import com.helger.commons.io.resource.FileSystemResource;
import com.helger.commons.io.resource.IReadableResource;
import com.helger.commons.io.resource.URLResource;
import com.helger.commons.io.stream.StreamHelper;
import com.helger.commons.system.SystemProperties;
import com.helger.commons.url.ISimpleURL;
/**
* Helper class to ease the use of {@link Properties} class.
*
* @author Philip Helger
*/
@Immutable
public final class PropertiesHelper
{
// No logger here!
private PropertiesHelper ()
{}
@Nonnull
@ReturnsMutableCopy
public static ICommonsMap getAsStringMap (@Nonnull final Properties aProps)
{
ValueEnforcer.notNull (aProps, "Props");
final ICommonsMap ret = new CommonsHashMap <> ();
for (final Map.Entry aEntry : aProps.entrySet ())
ret.put ((String) aEntry.getKey (), (String) aEntry.getValue ());
return ret;
}
@Nullable
public static NonBlockingProperties loadProperties (@Nonnull final ISimpleURL aURL)
{
ValueEnforcer.notNull (aURL, "URL");
try
{
return loadProperties (new URLResource (aURL));
}
catch (final MalformedURLException ex)
{
return null;
}
}
@Nullable
public static NonBlockingProperties loadProperties (@Nonnull final File aFile)
{
ValueEnforcer.notNull (aFile, "File");
return loadProperties (new FileSystemResource (aFile));
}
@Nullable
public static NonBlockingProperties loadProperties (@Nonnull final File aFile, @Nonnull final Charset aCharset)
{
ValueEnforcer.notNull (aFile, "File");
return loadProperties (new FileSystemResource (aFile), aCharset);
}
@Nullable
public static NonBlockingProperties loadProperties (@Nonnull final IReadableResource aRes)
{
ValueEnforcer.notNull (aRes, "Resource");
final InputStream aIS = aRes.getInputStream ();
if (aIS == null)
return null;
return loadProperties (aIS);
}
@Nullable
public static NonBlockingProperties loadProperties (@Nonnull final IReadableResource aRes, @Nonnull final Charset aCharset)
{
ValueEnforcer.notNull (aRes, "Resource");
ValueEnforcer.notNull (aCharset, "Charset");
final Reader aReader = aRes.getReader (aCharset);
if (aReader == null)
return null;
return loadProperties (aReader);
}
@Nullable
public static NonBlockingProperties loadProperties (@Nonnull @WillClose final InputStream aIS)
{
ValueEnforcer.notNull (aIS, "InputStream");
final InputStream aBufferedIS = StreamHelper.getBuffered (aIS);
try
{
final NonBlockingProperties aProps = new NonBlockingProperties ();
aProps.load (aBufferedIS);
return aProps;
}
catch (final IOException ex)
{
return null;
}
finally
{
StreamHelper.close (aBufferedIS);
StreamHelper.close (aIS);
}
}
@Nullable
public static NonBlockingProperties loadProperties (@Nonnull @WillClose final Reader aReader)
{
ValueEnforcer.notNull (aReader, "Reader");
final Reader aBufferedReader = StreamHelper.getBuffered (aReader);
try
{
final NonBlockingProperties aProps = new NonBlockingProperties ();
aProps.load (aBufferedReader);
return aProps;
}
catch (final IOException ex)
{
return null;
}
finally
{
StreamHelper.close (aBufferedReader);
StreamHelper.close (aReader);
}
}
/**
* Copy of Oracle internal PropertyExpander.expand method
*
* @param sValue
* Source value. May be null.
* @return null if source is null.
* @see #expandProperties(String, Function)
*/
@Nullable
public static String expandSystemProperties (@Nullable final String sValue)
{
return expandProperties (sValue, SystemProperties::getPropertyValue);
}
/**
* Special version of {@link #expandSystemProperties(String)} that takes an
* arbitrary value provider and is not limited to system properties.
*
* @param sValue
* Source value. May be null.
* @param aValueProvider
* The value provider to be used. May not be null.
* @return null if the source value is null.
* @since 9.1.2
*/
@Nullable
public static String expandProperties (@Nullable final String sValue, @Nonnull final Function aValueProvider)
{
ValueEnforcer.notNull (aValueProvider, "ValueProvider");
if (sValue == null)
return null;
int nIndex = sValue.indexOf ("${", 0);
// no special characters
if (nIndex == -1)
return sValue;
final StringBuilder aSB = new StringBuilder (sValue.length ());
final int nMax = sValue.length ();
// index of last character we copied
int nCurPos = 0;
while (nIndex < nMax)
{
if (nIndex > nCurPos)
{
// copy in anything before the special stuff
aSB.append (sValue.substring (nCurPos, nIndex));
}
int pe = nIndex + 2;
// do not expand ${{ ... }}
if (pe < nMax && sValue.charAt (pe) == '{')
{
pe = sValue.indexOf ("}}", pe);
if (pe == -1 || pe + 2 == nMax)
{
// append remaining chars
aSB.append (sValue.substring (nIndex));
break;
}
// append as normal text
pe++;
aSB.append (sValue.substring (nIndex, pe + 1));
}
else
{
while (pe < nMax && sValue.charAt (pe) != '}')
pe++;
if (pe == nMax)
{
// no matching '}' found, just add in as normal text
aSB.append (sValue.substring (nIndex, pe));
break;
}
final String sPropName = sValue.substring (nIndex + 2, pe);
if (sPropName.equals ("/"))
{
aSB.append (File.separatorChar);
}
else
{
final String sPropVal = aValueProvider.apply (sPropName);
if (sPropVal == null)
{
// Return original value
return sValue;
}
aSB.append (sPropVal);
}
}
nCurPos = pe + 1;
nIndex = sValue.indexOf ("${", nCurPos);
if (nIndex == -1)
{
// no more to expand. copy in any extra
if (nCurPos < nMax)
aSB.append (sValue.substring (nCurPos, nMax));
// break out of loop
break;
}
}
return aSB.toString ();
}
}