Update InternalStringBuilder.java to remove now useless _shared logic, and handle OOM on array copy gracefully

This commit is contained in:
Travis Burtrum 2019-01-08 15:28:23 -05:00
parent c351d203d6
commit ae29ec9928
1 changed files with 10 additions and 20 deletions

View File

@ -19,6 +19,7 @@
package org.apache.beehive.netui.util.internal; package org.apache.beehive.netui.util.internal;
import java.io.Serializable; import java.io.Serializable;
import java.lang.ref.SoftReference;
/** /**
@ -29,7 +30,6 @@ public final class InternalStringBuilder
{ {
private char _buffer[]; private char _buffer[];
private int _length = 0; private int _length = 0;
private boolean _shared;
static final long serialVersionUID = 1; static final long serialVersionUID = 1;
@ -41,7 +41,6 @@ public final class InternalStringBuilder
public InternalStringBuilder( int length ) public InternalStringBuilder( int length )
{ {
_buffer = new char[length]; _buffer = new char[length];
_shared = false;
} }
public InternalStringBuilder( String str ) public InternalStringBuilder( String str )
@ -55,17 +54,6 @@ public final class InternalStringBuilder
return _length; return _length;
} }
private final void copyWhenShared()
{
if ( _shared )
{
char newValue[] = new char[_buffer.length];
System.arraycopy( _buffer, 0, newValue, 0, _length );
_buffer = newValue;
_shared = false;
}
}
public void ensureCapacity( int minCapacity ) public void ensureCapacity( int minCapacity )
{ {
int maxCapacity = _buffer.length; int maxCapacity = _buffer.length;
@ -73,11 +61,17 @@ public final class InternalStringBuilder
if ( minCapacity > maxCapacity ) if ( minCapacity > maxCapacity )
{ {
int newCapacity = ( maxCapacity + 1 ) * 2; int newCapacity = ( maxCapacity + 1 ) * 2;
if ( minCapacity > newCapacity ) newCapacity = minCapacity; if ( newCapacity < 0 ) newCapacity = Integer.MAX_VALUE;
char newValue[] = new char[newCapacity]; else if ( minCapacity > newCapacity ) newCapacity = minCapacity;
// allow _buffer to be GCd if needed, rather than throw OOM
final SoftReference<char[]> softBuffer = new SoftReference<char[]>(_buffer);
_buffer = null;
final char newValue[] = new char[newCapacity];
_buffer = softBuffer.get();
if (_buffer == null)
throw new OutOfMemoryError("could not increase capacity in InternalStringBuilder");
System.arraycopy( _buffer, 0, newValue, 0, _length ); System.arraycopy( _buffer, 0, newValue, 0, _length );
_buffer = newValue; _buffer = newValue;
_shared = false;
} }
} }
@ -88,7 +82,6 @@ public final class InternalStringBuilder
if ( _length < length ) if ( _length < length )
{ {
copyWhenShared();
while ( _length < length ) while ( _length < length )
{ {
_buffer[_length++] = '\0'; _buffer[_length++] = '\0';
@ -113,7 +106,6 @@ public final class InternalStringBuilder
if ( str == null ) str = String.valueOf( str ); if ( str == null ) str = String.valueOf( str );
int len = str.length(); int len = str.length();
ensureCapacity( _length + len ); ensureCapacity( _length + len );
copyWhenShared();
str.getChars( 0, len, _buffer, _length ); str.getChars( 0, len, _buffer, _length );
_length += len; _length += len;
return this; return this;
@ -122,7 +114,6 @@ public final class InternalStringBuilder
public InternalStringBuilder append( char c ) public InternalStringBuilder append( char c )
{ {
ensureCapacity( _length + 1 ); ensureCapacity( _length + 1 );
copyWhenShared();
_buffer[_length++] = c; _buffer[_length++] = c;
return this; return this;
} }
@ -134,7 +125,6 @@ public final class InternalStringBuilder
public String toString() public String toString()
{ {
_shared = true;
return new String( _buffer, 0, _length ); return new String( _buffer, 0, _length );
} }