net.coobird.thumbnailator.util
Enum Configurations

java.lang.Object
  java.lang.Enum<Configurations>
      net.coobird.thumbnailator.util.Configurations

All Implemented Interfaces:

Serializable, Comparable<Configurations>

public enum Configurations
extends Enum<Configurations>

This enum lists properties that affect the behavior of Thumbnailator. Most are used for enabling or disabling workarounds.

Implementation note

The values for properties listed here will be read from the system properties via System.getProperty(String), therefore, can be set via the -D options when invoking the JVM. Alternatively, they can be included in thumbnailator.properties on the classpath (of the current thread's class loader.)

Disclaimer

Properties listed here are not part of Thumbnailator's public API. Therefore, code invoking Thumbnailator should not depend on these workarounds always being present.

Enum Constant Summary

CONSERVE_MEMORY_WORKAROUND
Enable a workaround to conserve memory when handling large image files.

DEBUG_LOG
Enable debug logging to standard error.

DEBUG_LOG_EXIF_WORKAROUND
Enable debug logging (to standard error) specifically for the Exif workaround.

DISABLE_EXIF_WORKAROUND
Disables the Exif workaround.

Method Summary

boolean	getBoolean() Returns whether the specified configuration is enabled or not.
static Configurations	valueOf(String name) Returns the enum constant of this type with the specified name.
static Configurations[]	values() Returns an array containing the constants of this enum type, in the order they're declared.

Methods inherited from class java.lang.Enum

compareTo, equals, getDeclaringClass, hashCode, name, ordinal, toString, valueOf

Methods inherited from class java.lang.Object

getClass, notify, notifyAll, wait, wait, wait

Enum Constant Detail

DISABLE_EXIF_WORKAROUND

public static final Configurations DISABLE_EXIF_WORKAROUND

Disables the Exif workaround. (Issue #108)
Property name: thumbnailator.disableExifWorkaround

The default JPEG reader bundled with the JRE cannot handle JPEG images that doesn't have a JFIF APP0 marker segment as the first one. Some JPEG images have Exif (APP1) as the first one.

A workaround was introduced to resolve issue #108 by capturing the Exif data from the bitstream rather than relying on the JPEG reader.

Disabling this workaround will prevent Thumbnailator from properly identifying the image orientation of JPEG images which have Exif as the first marker. Therefore, unless the default behavior causes issues, disabling this workaround is not recommended.

DEBUG_LOG

public static final Configurations DEBUG_LOG

Enable debug logging to standard error. This will enable debug logging throughout Thumbnailator.
Property name: thumbnailator.debugLog

DEBUG_LOG_EXIF_WORKAROUND

public static final Configurations DEBUG_LOG_EXIF_WORKAROUND

Enable debug logging (to standard error) specifically for the Exif workaround.
Property name: thumbnailator.debugLog.exifWorkaround

CONSERVE_MEMORY_WORKAROUND

public static final Configurations CONSERVE_MEMORY_WORKAROUND

Enable a workaround to conserve memory when handling large image files. (Issue #69)

It is known that OutOfMemoryErrors can occur when handling large images in Thumbnailator.

To fundamentally address the issue requires some dramatic design changes to the core parts of Thumbnailator which would take some time and would affect many internal parts of the library. Such changes would take time before being implemented, a workaround has been implemented in Thumbnailator 0.4.8 to reduce the likeliness of OutOfMemoryErrors.

The workaround is not enabled by default, as it can negatively affect the quality of the final image. It has also not been extensively tested and will not necessarily prevent OutOfMemoryErrors.

When the workaround enabled, a smaller version of the source image will be used to reduce memory usage, under the following conditions:

• Both height and width have dimensions larger than 1800 pixels
• The expected memory size of the source image will take up more than 1/4 of the available JVM free memory

Method Detail

values

public static final Configurations[] values()

Returns an array containing the constants of this enum type, in the order they're declared. This method may be used to iterate over the constants as follows:

for(Configurations c : Configurations.values())
        System.out.println(c);

Returns:

an array containing the constants of this enum type, in the order they're declared

valueOf

public static Configurations valueOf(String name)

Returns the enum constant of this type with the specified name. The string must match exactly an identifier used to declare an enum constant in this type. (Extraneous whitespace characters are not permitted.)

Parameters:

name - the name of the enum constant to be returned.

Returns:

the enum constant with the specified name

Throws:

IllegalArgumentException - if this enum type has no constant with the specified name

getBoolean

public boolean getBoolean()

Returns whether the specified configuration is enabled or not.

Returns:

true if the configuration is enabled, false otherwise.