Package org.codehaus.groovy.control

# Class CompilerConfiguration

java.lang.Object
org.codehaus.groovy.control.CompilerConfiguration

public class CompilerConfiguration extends Object
Compilation control flags and coordination stuff.

- ## Field Summary

  Fields
  Modifier and Type
  Field
  Description
  `static final String[]`
  `ALLOWED_JDKS`
  The valid targetBytecode values.
  `static final int`
  `ASM_API_VERSION`
  The ASM API version used when loading/parsing classes and generating proxy adapter classes.
  `static final String`
  `CLOSURE_PACKING`
  System-property name for the GEP-27 incubating option that automatically packs provably-safe `@CompileStatic` closures (hoisting their bodies to a shared adapter instead of a class).
  `static final String`
  `CLOSURE_PACKING_REPORT`
  System-property name for the GEP-27 incubating option that, on the `CLOSURE_PACKING` path, reports (as compiler warnings) each closure that could not be packed and why.
  `static final CompilerConfiguration`
  `DEFAULT`
  A convenience for getting a default configuration.
  `static final String`
  `DEFAULT_SOURCE_ENCODING`
  The default source encoding.
  `static final String`
  `DEFAULT_TARGET_BYTECODE`
  `static final int`
  `DEFAULT_TOLERANCE`
  The default number of non-fatal errors tolerated before compilation is aborted.
  `static final String`
  `ERROR_RECOVERY`
  Option for enabling ANTLR parser error recovery on the Parrot parser.
  `static final String`
  `GROOVYDOC`
  Optimization Option for enabling attaching groovydoc as AST node metadata.
  `static final String`
  `INVOKEDYNAMIC`
  Optimization Option for enabling `invokedynamic` compilation.
  `static final Map<String,Integer>`
  `JDK_TO_BYTECODE_VERSION_MAP`
  JDK version to bytecode version mapping.
  `static final String`
  `JDK10`
  Deprecated.
  `static final String`
  `JDK11`
  Deprecated.
  `static final String`
  `JDK12`
  Deprecated.
  `static final String`
  `JDK13`
  Deprecated.
  `static final String`
  `JDK14`
  Deprecated.
  `static final String`
  `JDK15`
  Deprecated.
  `static final String`
  `JDK16`
  Deprecated.
  `static final String`
  `JDK17`
  This (`"17"`) is the value for targetBytecode to compile for a JDK 17.
  `static final String`
  `JDK18`
  This (`"18"`) is the value for targetBytecode to compile for a JDK 18.
  `static final String`
  `JDK19`
  This (`"19"`) is the value for targetBytecode to compile for a JDK 19.
  `static final String`
  `JDK20`
  This (`"20"`) is the value for targetBytecode to compile for a JDK 20.
  `static final String`
  `JDK21`
  This (`"21"`) is the value for targetBytecode to compile for a JDK 21.
  `static final String`
  `JDK22`
  This (`"22"`) is the value for targetBytecode to compile for a JDK 22.
  `static final String`
  `JDK23`
  This (`"23"`) is the value for targetBytecode to compile for a JDK 23.
  `static final String`
  `JDK24`
  This (`"24"`) is the value for targetBytecode to compile for a JDK 24.
  `static final String`
  `JDK25`
  This (`"25"`) is the value for targetBytecode to compile for a JDK 25.
  `static final String`
  `JDK26`
  This (`"26"`) is the value for targetBytecode to compile for a JDK 26.
  `static final String`
  `JDK27`
  This (`"27"`) is the value for targetBytecode to compile for a JDK 27.
  `static final String`
  `JDK4`
  Deprecated.
  `static final String`
  `JDK5`
  Deprecated.
  `static final String`
  `JDK6`
  Deprecated.
  `static final String`
  `JDK7`
  Deprecated.
  `static final String`
  `JDK8`
  Deprecated.
  `static final String`
  `JDK9`
  Deprecated.
  `static final String`
  `LAMBDA_HOISTING`
  System-property name for the GEP-27 incubating option that hoists eligible SAM lambdas to a metafactory method instead of generating a per-lambda class.
  `static final String`
  `MEM_STUB`
  Joint Compilation Option for enabling generating stubs in memory.
  `static final String`
  `PARALLEL_PARSE`
  Optimization Option for enabling parallel parsing.
  `static final String`
  `RUNTIME_GROOVYDOC`
  Optimization Option for enabling attaching `Groovydoc` annotation.

- ## Constructor Summary

  Constructors
  Constructor
  Description
  `CompilerConfiguration()`
  Sets the compiler flags/settings to default values.
  `CompilerConfiguration(Properties configuration)`
  Sets the configuration flags/settings according to values from the supplied `Properties` instance or if not found, supplying a default value.
  `CompilerConfiguration(CompilerConfiguration configuration)`
  Copy constructor.
  `CompilerConfiguration(CompilerConfiguration configuration, boolean copyCustomizers)`
  Copy constructor which optionally omits the supplied configuration's `compilation customizers`.

- ## Method Summary

  Modifier and Type
  Method
  Description
  `CompilerConfiguration`
  `addCompilationCustomizers(CompilationCustomizer... customizers)`
  Adds compilation customizers to the compilation process.
  `void`
  `configure(Properties configuration)`
  Method to configure a CompilerConfiguration by using Properties.
  `BytecodeProcessor`
  `getBytecodePostprocessor()`
  Returns the optional bytecode post-processor.
  `final int`
  `getBytecodeVersion()`
  Returns the targeted bytecode (aka Java class file) version number.
  `List<String>`
  `getClasspath()`
  `List<CompilationCustomizer>`
  `getCompilationCustomizers()`
  Returns the list of compilation customizers.
  `boolean`
  `getDebug()`
  Returns true if debugging operation has been requested.
  `String`
  `getDefaultScriptExtension()`
  Returns the default file extension used for generated scripts.
  `Set<String>`
  `getDisabledGlobalASTTransformations()`
  Returns the list of disabled global AST transformation class names.
  `ErrorFormat`
  `getErrorFormat()`
  Returns how compilation errors and warnings are rendered.
  `Map<String,Object>`
  `getJointCompilationOptions()`
  Gets the joint compilation options for this configuration.
  `int`
  `getLogClassgenStackTraceMaxDepth()`
  Returns stack trace max depth of logging class generation
  `int`
  `getMinimumRecompilationInterval()`
  Returns the minimum interval between recompilation checks.
  `Map<String,Boolean>`
  `getOptimizationOptions()`
  Gets the optimization options for this configuration.
  `PrintWriter`
  `getOutput()`
  Deprecated.
  not used anymore
  `boolean`
  `getParameters()`
  Returns true if parameter metadata generation has been enabled.
  `ParserPluginFactory`
  `getPluginFactory()`
  Returns the parser plugin factory to use for source parsing.
  `boolean`
  `getRecompileGroovySource()`
  Indicates whether Groovy sources should be recompiled when they change.
  `String`
  `getScriptBaseClass()`
  Gets the name of the base class for scripts.
  `Set<String>`
  `getScriptExtensions()`
  Returns the recognized script file extensions.
  `String`
  `getSourceEncoding()`
  Gets the currently configured source file encoding.
  `String`
  `getTargetBytecode()`
  Retrieves the compiler bytecode compatibility level.
  `File`
  `getTargetDirectory()`
  Gets the target directory for writing classes.
  `int`
  `getTargetPhase()`
  Gets the target compile phase: the last phase to be processed when `CompilationUnit.compile()` is called without an explicit phase.
  `int`
  `getTolerance()`
  Returns the requested error tolerance.
  `boolean`
  `getVerbose()`
  Returns true if verbose operation has been requested.
  `int`
  `getWarningLevel()`
  Gets the currently configured warning level.
  `boolean`
  `isClassTagPreemptionDisabled()`
  Whether `@ClassTag` preemption is disabled globally under static compilation (GROOVY-12115).
  `boolean`
  `isErrorRecoveryEnabled()`
  Checks if ANTLR parser error recovery is enabled.
  `boolean`
  `isForInPerIterationCaptureEnabled()`
  Checks if per-iteration capture of for-in (enhanced for-each) loop variables is enabled (GROOVY-11792).
  `boolean`
  `isGroovydocEnabled()`
  Checks if groovydoc is enabled.
  `boolean`
  `isIndyEnabled()`
  Checks if invoke dynamic is enabled.
  `boolean`
  `isLogClassgen()`
  Returns whether logging class generation is enabled
  `static boolean`
  `isPostJDK10(String bytecodeVersion)`
  Deprecated.
  `static boolean`
  `isPostJDK11(String bytecodeVersion)`
  Deprecated.
  `static boolean`
  `isPostJDK12(String bytecodeVersion)`
  Deprecated.
  `static boolean`
  `isPostJDK13(String bytecodeVersion)`
  Deprecated.
  `static boolean`
  `isPostJDK14(String bytecodeVersion)`
  Deprecated.
  `static boolean`
  `isPostJDK15(String bytecodeVersion)`
  Deprecated.
  `static boolean`
  `isPostJDK16(String bytecodeVersion)`
  Deprecated.
  `static boolean`
  `isPostJDK17(String bytecodeVersion)`
  Checks if the specified bytecode version string represents a JDK 17+ compatible bytecode version.
  `static boolean`
  `isPostJDK18(String bytecodeVersion)`
  Checks if the specified bytecode version string represents a JDK 18+ compatible bytecode version.
  `static boolean`
  `isPostJDK5(String bytecodeVersion)`
  Deprecated.
  `static boolean`
  `isPostJDK7(String bytecodeVersion)`
  Deprecated.
  `static boolean`
  `isPostJDK8(String bytecodeVersion)`
  Deprecated.
  `static boolean`
  `isPostJDK9(String bytecodeVersion)`
  Deprecated.
  `boolean`
  `isPreviewFeatures()`
  Whether the bytecode version has preview features enabled (JEP 12)
  `boolean`
  `isRuntimeGroovydocEnabled()`
  Checks if runtime groovydoc is enabled.
  `void`
  `setBytecodePostprocessor(BytecodeProcessor bytecodePostprocessor)`
  Sets the bytecode post-processor applied to generated classes.
  `void`
  `setClasspath(String classpath)`
  Sets the classpath.
  `void`
  `setClasspathList(List<String> parts)`
  sets the classpath using a list of Strings
  `void`
  `setClassTagPreemptionDisabled(boolean classTagPreemptionDisabled)`
  Disables (or re-enables) `@ClassTag` preemption globally under static compilation (GROOVY-12115).
  `void`
  `setDebug(boolean debug)`
  Turns debugging operation on or off.
  `void`
  `setDefaultScriptExtension(String defaultScriptExtension)`
  Sets the default file extension used for generated scripts.
  `void`
  `setDisabledGlobalASTTransformations(Set<String> disabledGlobalASTTransformations)`
  Disables the specified global AST transformations.
  `void`
  `setErrorFormat(ErrorFormat errorFormat)`
  Sets how compilation errors and warnings are rendered.
  `void`
  `setForInPerIterationCaptureEnabled(boolean forInPerIterationCapture)`
  Enables or disables per-iteration capture of for-in (enhanced for-each) loop variables shared with closures, lambdas, or anonymous inner classes (GROOVY-11792).
  `void`
  `setJointCompilationOptions(Map<String,Object> options)`
  Sets the joint compilation options for this configuration.
  `void`
  `setLogClassgen(boolean logClassgen)`
  Sets whether logging class generation is enabled
  `void`
  `setLogClassgenStackTraceMaxDepth(int logClassgenStackTraceMaxDepth)`
  Sets stack trace max depth of logging class generation
  `void`
  `setMinimumRecompilationInterval(int time)`
  Sets the minimum interval between recompilation checks.
  `void`
  `setOptimizationOptions(Map<String,Boolean> options)`
  Sets the optimization options for this configuration.
  `void`
  `setOutput(PrintWriter output)`
  Deprecated.
  not used anymore, has no effect
  `void`
  `setParameters(boolean parameters)`
  Turns parameter metadata generation on or off.
  `void`
  `setPluginFactory(ParserPluginFactory pluginFactory)`
  Sets the parser plugin factory to use for source parsing.
  `void`
  `setPreviewFeatures(boolean previewFeatures)`
  Sets whether the bytecode version has preview features enabled (JEP 12).
  `void`
  `setRecompileGroovySource(boolean recompile)`
  Sets whether changed Groovy sources should be recompiled.
  `void`
  `setScriptBaseClass(String scriptBaseClass)`
  Sets the name of the base class for scripts.
  `void`
  `setScriptExtensions(Set<String> scriptExtensions)`
  Replaces the set of recognized script file extensions.
  `void`
  `setSourceEncoding(String encoding)`
  Sets the encoding to be used when reading source files.
  `void`
  `setTargetBytecode(String version)`
  Sets the bytecode compatibility level.
  `void`
  `setTargetDirectory(File directory)`
  Sets the target directory.
  `void`
  `setTargetDirectory(String directory)`
  Sets the target directory.
  `void`
  `setTargetPhase(int targetPhase)`
  Sets the target compile phase: the last phase to be processed when `CompilationUnit.compile()` is called without an explicit phase.
  `void`
  `setTargetPhase(CompilePhase targetPhase)`
  Convenience overload of `setTargetPhase(int)` taking the `CompilePhase` enum, e.g.
  `void`
  `setTolerance(int tolerance)`
  Sets the error tolerance, which is the number of non-fatal errors (per unit) that should be tolerated before compilation is aborted.
  `void`
  `setVerbose(boolean verbose)`
  Turns verbose operation on or off.
  `void`
  `setWarningLevel(int level)`
  Sets the warning level.

  ### Methods inherited from class java.lang.Object

  `clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait`

- ## Field Details

  - ### INVOKEDYNAMIC

    public static final String INVOKEDYNAMIC
    Optimization Option for enabling `invokedynamic` compilation.
    See Also:
      - Constant Field Values

  - ### GROOVYDOC

    public static final String GROOVYDOC
    Optimization Option for enabling attaching groovydoc as AST node metadata.
    See Also:
      - Constant Field Values

  - ### RUNTIME_GROOVYDOC

    public static final String RUNTIME_GROOVYDOC
    Optimization Option for enabling attaching `Groovydoc` annotation.
    See Also:
      - Constant Field Values

  - ### PARALLEL_PARSE

    public static final String PARALLEL_PARSE
    Optimization Option for enabling parallel parsing.
    See Also:
      - Constant Field Values

  - ### ERROR_RECOVERY

    public static final String ERROR_RECOVERY
    Option for enabling ANTLR parser error recovery on the Parrot parser.

    Disabled by default. When enabled (typically for IDE editing), the parser resynchronizes after recognition errors so multiple diagnostics can be collected in one pass instead of failing fast on the first error. Stored in `getOptimizationOptions()` for consistency with other compiler feature flags (e.g. `GROOVYDOC`).

    Since:
      5.0.0
    See Also:
      - `isErrorRecoveryEnabled()`
      - Constant Field Values

  - ### MEM_STUB

    public static final String MEM_STUB
    Joint Compilation Option for enabling generating stubs in memory.
    See Also:
      - Constant Field Values

  - ### CLOSURE_PACKING

    @Incubating public static final String CLOSURE_PACKING
    System-property name for the GEP-27 incubating option that automatically packs provably-safe `@CompileStatic` closures (hoisting their bodies to a shared adapter instead of a class). Incubating: this switch may change or be removed until the feature graduates.
    See Also:
      - Constant Field Values

  - ### CLOSURE_PACKING_REPORT

    @Incubating public static final String CLOSURE_PACKING_REPORT
    System-property name for the GEP-27 incubating option that, on the `CLOSURE_PACKING` path, reports (as compiler warnings) each closure that could not be packed and why.
    See Also:
      - Constant Field Values

  - ### LAMBDA_HOISTING

    @Incubating public static final String LAMBDA_HOISTING
    System-property name for the GEP-27 incubating option that hoists eligible SAM lambdas to a metafactory method instead of generating a per-lambda class.
    See Also:
      - Constant Field Values

  - ### JDK4

    @Deprecated public static final String JDK4
    Deprecated.
    This (`"1.4"`) is the value for targetBytecode to compile for a JDK 1.4.
    See Also:
      - Constant Field Values

  - ### JDK5

    @Deprecated public static final String JDK5
    Deprecated.
    This (`"1.5"`) is the value for targetBytecode to compile for a JDK 1.5.
    See Also:
      - Constant Field Values

  - ### JDK6

    @Deprecated public static final String JDK6
    Deprecated.
    This (`"1.6"`) is the value for targetBytecode to compile for a JDK 1.6.
    See Also:
      - Constant Field Values

  - ### JDK7

    @Deprecated public static final String JDK7
    Deprecated.
    This (`"1.7"`) is the value for targetBytecode to compile for a JDK 1.7.
    See Also:
      - Constant Field Values

  - ### JDK8

    @Deprecated public static final String JDK8
    Deprecated.
    This (`"1.8"`) is the value for targetBytecode to compile for a JDK 1.8.
    See Also:
      - Constant Field Values

  - ### JDK9

    @Deprecated public static final String JDK9
    Deprecated.
    This (`"9"`) is the value for targetBytecode to compile for a JDK 9.
    See Also:
      - Constant Field Values

  - ### JDK10

    @Deprecated public static final String JDK10
    Deprecated.
    This (`"10"`) is the value for targetBytecode to compile for a JDK 10.
    See Also:
      - Constant Field Values

  - ### JDK11

    @Deprecated public static final String JDK11
    Deprecated.
    This (`"11"`) is the value for targetBytecode to compile for a JDK 11.
    See Also:
      - Constant Field Values

  - ### JDK12

    @Deprecated public static final String JDK12
    Deprecated.
    This (`"12"`) is the value for targetBytecode to compile for a JDK 12.
    See Also:
      - Constant Field Values

  - ### JDK13

    @Deprecated public static final String JDK13
    Deprecated.
    This (`"13"`) is the value for targetBytecode to compile for a JDK 13.
    See Also:
      - Constant Field Values

  - ### JDK14

    @Deprecated public static final String JDK14
    Deprecated.
    This (`"14"`) is the value for targetBytecode to compile for a JDK 14.
    See Also:
      - Constant Field Values

  - ### JDK15

    @Deprecated public static final String JDK15
    Deprecated.
    This (`"15"`) is the value for targetBytecode to compile for a JDK 15.
    See Also:
      - Constant Field Values

  - ### JDK16

    @Deprecated public static final String JDK16
    Deprecated.
    This (`"16"`) is the value for targetBytecode to compile for a JDK 16.
    See Also:
      - Constant Field Values

  - ### JDK17

    public static final String JDK17
    This (`"17"`) is the value for targetBytecode to compile for a JDK 17.
    See Also:
      - Constant Field Values

  - ### JDK18

    public static final String JDK18
    This (`"18"`) is the value for targetBytecode to compile for a JDK 18.
    See Also:
      - Constant Field Values

  - ### JDK19

    public static final String JDK19
    This (`"19"`) is the value for targetBytecode to compile for a JDK 19.
    See Also:
      - Constant Field Values

  - ### JDK20

    public static final String JDK20
    This (`"20"`) is the value for targetBytecode to compile for a JDK 20.
    See Also:
      - Constant Field Values

  - ### JDK21

    public static final String JDK21
    This (`"21"`) is the value for targetBytecode to compile for a JDK 21.
    See Also:
      - Constant Field Values

  - ### JDK22

    public static final String JDK22
    This (`"22"`) is the value for targetBytecode to compile for a JDK 22.
    See Also:
      - Constant Field Values

  - ### JDK23

    public static final String JDK23
    This (`"23"`) is the value for targetBytecode to compile for a JDK 23.
    See Also:
      - Constant Field Values

  - ### JDK24

    public static final String JDK24
    This (`"24"`) is the value for targetBytecode to compile for a JDK 24.
    See Also:
      - Constant Field Values

  - ### JDK25

    public static final String JDK25
    This (`"25"`) is the value for targetBytecode to compile for a JDK 25.
    See Also:
      - Constant Field Values

  - ### JDK26

    public static final String JDK26
    This (`"26"`) is the value for targetBytecode to compile for a JDK 26.
    See Also:
      - Constant Field Values

  - ### JDK27

    public static final String JDK27
    This (`"27"`) is the value for targetBytecode to compile for a JDK 27.
    See Also:
      - Constant Field Values

  - ### JDK_TO_BYTECODE_VERSION_MAP

    public static final Map<String,Integer> JDK_TO_BYTECODE_VERSION_MAP
    JDK version to bytecode version mapping.

  - ### DEFAULT_TARGET_BYTECODE

    public static final String DEFAULT_TARGET_BYTECODE

  - ### ALLOWED_JDKS

    public static final String[] ALLOWED_JDKS
    The valid targetBytecode values.

  - ### ASM_API_VERSION

    public static final int ASM_API_VERSION
    The ASM API version used when loading/parsing classes and generating proxy adapter classes.
    See Also:
      - Constant Field Values

  - ### DEFAULT_SOURCE_ENCODING

    public static final String DEFAULT_SOURCE_ENCODING
    The default source encoding.
    See Also:
      - Constant Field Values

  - ### DEFAULT_TOLERANCE

    public static final int DEFAULT_TOLERANCE
    The default number of non-fatal errors tolerated before compilation is aborted.
    Since:
      6.0.0
    See Also:
      - `setTolerance(int)`
      - Constant Field Values

  - ### DEFAULT

    public static final CompilerConfiguration DEFAULT
    A convenience for getting a default configuration. Do not modify it! See `CompilerConfiguration(Properties)` for an example on how to make a suitable copy to modify. But if you're really starting from a default context, then you probably just want `new CompilerConfiguration()`.

- ## Constructor Details

  - ### CompilerConfiguration

    public CompilerConfiguration()
    Sets the compiler flags/settings to default values. The following system properties are referenced when setting the configuration:

    > Property Key | Related Property Getter
    > --- | ---
    > `groovy.source.encoding` (defaulting to `file.encoding`) | `getSourceEncoding()`
    > `groovy.target.bytecode` | `getTargetBytecode()`
    > `groovy.target.directory` | `getTargetDirectory()`
    > `groovy.parameters` | `getParameters()`
    > `groovy.preview.features` | `isPreviewFeatures()`
    > `groovy.default.scriptExtension` | `getDefaultScriptExtension()`

    The following system properties are referenced when setting the configuration optimization options:

    > Property Key | Related Property Getter
    > --- | ---
    > `groovy.target.indy` | `getOptimizationOptions()`
    > `groovy.parallel.parse` | `getOptimizationOptions()`
    > `groovy.attach.groovydoc` | `getOptimizationOptions()`
    > `groovy.attach.runtime.groovydoc` | `getOptimizationOptions()`
    > `groovy.parser.error.recovery` | `getOptimizationOptions()` / `isErrorRecoveryEnabled()`

    Additional language-compatibility system properties (not optimization options):

    > Property Key | Related Property Getter
    > --- | ---
    > `groovy.forin.per.iteration.capture` | `isForInPerIterationCaptureEnabled()`

  - ### CompilerConfiguration

    public CompilerConfiguration(CompilerConfiguration configuration)
    Copy constructor. Use this if you have a mostly correct configuration for your compilation but you want to make a some changes programmatically. An important reason to prefer this approach is that your code will most likely be forward compatible with future changes to this configuration API.

    An example of this copy constructor at work:

    >      // In all likelihood there is already a configuration in your code's context
    >      // for you to copy, but for the sake of this example we'll use the global default.
    >      CompilerConfiguration myConfiguration = new CompilerConfiguration(CompilerConfiguration.DEFAULT);
    >      myConfiguration.setDebug(true);

    The supplied configuration's `compilation customizers` are copied along with everything else. Prior to Groovy 6, they were not; code which copies a configuration and then adds its own customizers will now see the copied ones as well as its own. Use `CompilerConfiguration(CompilerConfiguration, boolean)` with `false` if you want only your own.

    Parameters:
      `configuration` - The configuration to copy.

  - ### CompilerConfiguration

    public CompilerConfiguration(CompilerConfiguration configuration, boolean copyCustomizers)
    Copy constructor which optionally omits the supplied configuration's `compilation customizers`.

    Pass `false` when deriving a configuration for a nested compilation, such as compiling a synthetic class node or a DSL script encountered while compiling something else. A customizer is registered for a particular compilation and commonly assumes its source units and class nodes, so applying one to a nested compilation may misbehave or fail outright.

    Parameters:
      `configuration` - The configuration to copy.
      `copyCustomizers` - whether to also copy the compilation customizers
    Since:
      6.0.0

  - ### CompilerConfiguration

    public CompilerConfiguration(Properties configuration) throws ConfigurationException
    Sets the configuration flags/settings according to values from the supplied `Properties` instance or if not found, supplying a default value. Note that unlike `CompilerConfiguration()`, the "defaults" here do not in general include checking the settings in `System.getProperties()`. If you want to set a few flags but keep Groovy's default configuration behavior then be sure to make your settings in a `Properties` object that is backed by `System.getProperties()` (which is done using this constructor). That might be done like this:

    >      Properties myProperties = new Properties(System.getProperties());
    >      myProperties.setProperty("groovy.output.debug", "true");
    >      myConfiguration = new CompilerConfiguration(myProperties);

    And you also have to contend with a possible `SecurityException` when getting the system properties (See `System.getProperties()`). A safer approach would be to copy a default `CompilerConfiguration` and make your changes there using the setter:

    >      // In all likelihood there is already a configuration for you to copy,
    >      // but for the sake of this example we'll use the global default.
    >      CompilerConfiguration myConfiguration = new CompilerConfiguration(CompilerConfiguration.DEFAULT);
    >      myConfiguration.setDebug(true);

    The following properties are referenced when setting the configuration:

    > Property Key | Related Property Getter
    > --- | ---
    > `groovy.warnings` | `getWarningLevel()`
    > `groovy.source.encoding` (defaulting to `file.encoding`) | `getSourceEncoding()`
    > `groovy.target.directory` | `getTargetDirectory()`
    > `groovy.target.bytecode` | `getTargetBytecode()`
    > `groovy.parameters` | `getParameters()`
    > `groovy.preview.features` | `isPreviewFeatures()`
    > `groovy.classpath` | `getClasspath()`
    > `groovy.output.verbose` | `getVerbose()`
    > `groovy.output.debug` | `getDebug()`
    > `groovy.errors.tolerance` | `getTolerance()`
    > `groovy.default.scriptExtension` | `getDefaultScriptExtension()`
    > `groovy.script.base` | `getScriptBaseClass()`
    > `groovy.recompile` | `getRecompileGroovySource()`
    > `groovy.recompile.minimumInterval` | `getMinimumRecompilationInterval()`
    > `groovy.disabled.global.ast.transformations` | `getDisabledGlobalASTTransformations()`
    > `groovy.forin.per.iteration.capture` | `isForInPerIterationCaptureEnabled()`

    Parameters:
      `configuration` - The properties to get flag values from.
    Throws:
      `ConfigurationException`

- ## Method Details

  - ### isPostJDK5

    @Deprecated public static boolean isPostJDK5(String bytecodeVersion)
    Deprecated.
    Checks if the specified bytecode version string represents a JDK 1.5+ compatible bytecode version.
    Parameters:
      `bytecodeVersion` - The parameter can take one of the values in `ALLOWED_JDKS`.
    Returns:
      true if the bytecode version is JDK 1.5+

  - ### isPostJDK7

    @Deprecated public static boolean isPostJDK7(String bytecodeVersion)
    Deprecated.
    Checks if the specified bytecode version string represents a JDK 1.7+ compatible bytecode version.
    Parameters:
      `bytecodeVersion` - The parameter can take one of the values in `ALLOWED_JDKS`.
    Returns:
      true if the bytecode version is JDK 1.7+

  - ### isPostJDK8

    @Deprecated public static boolean isPostJDK8(String bytecodeVersion)
    Deprecated.
    Checks if the specified bytecode version string represents a JDK 1.8+ compatible bytecode version.
    Parameters:
      `bytecodeVersion` - The parameter can take one of the values in `ALLOWED_JDKS`.
    Returns:
      true if the bytecode version is JDK 1.8+

  - ### isPostJDK9

    @Deprecated public static boolean isPostJDK9(String bytecodeVersion)
    Deprecated.
    Checks if the specified bytecode version string represents a JDK 9+ compatible bytecode version.
    Parameters:
      `bytecodeVersion` - The parameter can take one of the values in `ALLOWED_JDKS`.
    Returns:
      true if the bytecode version is JDK 9+

  - ### isPostJDK10

    @Deprecated public static boolean isPostJDK10(String bytecodeVersion)
    Deprecated.
    Checks if the specified bytecode version string represents a JDK 10+ compatible bytecode version.
    Parameters:
      `bytecodeVersion` - The parameter can take one of the values in `ALLOWED_JDKS`.
    Returns:
      true if the bytecode version is JDK 10+

  - ### isPostJDK11

    @Deprecated public static boolean isPostJDK11(String bytecodeVersion)
    Deprecated.
    Checks if the specified bytecode version string represents a JDK 11+ compatible bytecode version.
    Parameters:
      `bytecodeVersion` - The parameter can take one of the values in `ALLOWED_JDKS`.
    Returns:
      true if the bytecode version is JDK 11+

  - ### isPostJDK12

    @Deprecated public static boolean isPostJDK12(String bytecodeVersion)
    Deprecated.
    Checks if the specified bytecode version string represents a JDK 12+ compatible bytecode version.
    Parameters:
      `bytecodeVersion` - The parameter can take one of the values in `ALLOWED_JDKS`.
    Returns:
      true if the bytecode version is JDK 12+

  - ### isPostJDK13

    @Deprecated public static boolean isPostJDK13(String bytecodeVersion)
    Deprecated.
    Checks if the specified bytecode version string represents a JDK 13+ compatible bytecode version.
    Parameters:
      `bytecodeVersion` - The parameter can take one of the values in `ALLOWED_JDKS`.
    Returns:
      true if the bytecode version is JDK 13+

  - ### isPostJDK14

    @Deprecated public static boolean isPostJDK14(String bytecodeVersion)
    Deprecated.
    Checks if the specified bytecode version string represents a JDK 14+ compatible bytecode version.
    Parameters:
      `bytecodeVersion` - The parameter can take one of the values in `ALLOWED_JDKS`.
    Returns:
      true if the bytecode version is JDK 14+

  - ### isPostJDK15

    @Deprecated public static boolean isPostJDK15(String bytecodeVersion)
    Deprecated.
    Checks if the specified bytecode version string represents a JDK 15+ compatible bytecode version.
    Parameters:
      `bytecodeVersion` - The parameter can take one of the values in `ALLOWED_JDKS`.
    Returns:
      true if the bytecode version is JDK 15+

  - ### isPostJDK16

    @Deprecated public static boolean isPostJDK16(String bytecodeVersion)
    Deprecated.
    Checks if the specified bytecode version string represents a JDK 16+ compatible bytecode version.
    Parameters:
      `bytecodeVersion` - The parameter can take one of the values in `ALLOWED_JDKS`.
    Returns:
      true if the bytecode version is JDK 16+

  - ### isPostJDK17

    public static boolean isPostJDK17(String bytecodeVersion)
    Checks if the specified bytecode version string represents a JDK 17+ compatible bytecode version.
    Parameters:
      `bytecodeVersion` - The parameter can take one of the values in `ALLOWED_JDKS`.
    Returns:
      true if the bytecode version is JDK 17+

  - ### isPostJDK18

    public static boolean isPostJDK18(String bytecodeVersion)
    Checks if the specified bytecode version string represents a JDK 18+ compatible bytecode version.
    Parameters:
      `bytecodeVersion` - The parameter can take one of the values in `ALLOWED_JDKS`.
    Returns:
      true if the bytecode version is JDK 18+

  - ### configure

    public void configure(Properties configuration) throws ConfigurationException
    Method to configure a CompilerConfiguration by using Properties. For a list of available properties look at `CompilerConfiguration(Properties)`.
    Parameters:
      `configuration` - The properties to get flag values from.
    Throws:
      `ConfigurationException`

  - ### getWarningLevel

    public int getWarningLevel()
    Gets the currently configured warning level. See `WarningMessage` for level details.

  - ### setWarningLevel

    public void setWarningLevel(int level)
    Sets the warning level. See `WarningMessage` for level details.

  - ### getSourceEncoding

    public String getSourceEncoding()
    Gets the currently configured source file encoding.

  - ### setSourceEncoding

    public void setSourceEncoding(String encoding)
    Sets the encoding to be used when reading source files.

  - ### getOutput

    @Deprecated public PrintWriter getOutput()
    Deprecated.
    not used anymore
    Gets the currently configured output writer.

  - ### setOutput

    @Deprecated public void setOutput(PrintWriter output)
    Deprecated.
    not used anymore, has no effect
    Sets the output writer.

  - ### getTargetDirectory

    public File getTargetDirectory()
    Gets the target directory for writing classes.

  - ### setTargetDirectory

    public void setTargetDirectory(String directory)
    Sets the target directory.

  - ### setTargetDirectory

    public void setTargetDirectory(File directory)
    Sets the target directory.

  - ### getClasspath

    public List<String> getClasspath()
    Returns:
      the classpath

  - ### setClasspath

    public void setClasspath(String classpath)
    Sets the classpath.

  - ### setClasspathList

    public void setClasspathList(List<String> parts)
    sets the classpath using a list of Strings
    Parameters:
      `parts` - list of strings containing the classpath parts

  - ### getVerbose

    public boolean getVerbose()
    Returns true if verbose operation has been requested.

  - ### setVerbose

    public void setVerbose(boolean verbose)
    Turns verbose operation on or off.

  - ### getDebug

    public boolean getDebug()
    Returns true if debugging operation has been requested.

  - ### setDebug

    public void setDebug(boolean debug)
    Turns debugging operation on or off.

  - ### getParameters

    public boolean getParameters()
    Returns true if parameter metadata generation has been enabled.

  - ### setParameters

    public void setParameters(boolean parameters)
    Turns parameter metadata generation on or off.

  - ### getTolerance

    public int getTolerance()
    Returns the requested error tolerance. Zero or less means unlimited.
    See Also:
      - `setTolerance(int)`

  - ### setTolerance

    public void setTolerance(int tolerance)
    Sets the error tolerance, which is the number of non-fatal errors (per unit) that should be tolerated before compilation is aborted. Defaults to 10.

    A value of zero or less means unlimited: every error is collected and reported, and compilation is never cut short by the error count alone (GROOVY-12306).

  - ### getScriptBaseClass

    public String getScriptBaseClass()
    Gets the name of the base class for scripts. It must be a subclass of Script.

  - ### setScriptBaseClass

    public void setScriptBaseClass(String scriptBaseClass)
    Sets the name of the base class for scripts. It must be a subclass of Script.

  - ### getPluginFactory

    public ParserPluginFactory getPluginFactory()
    Returns the parser plugin factory to use for source parsing.
    Returns:
      the configured parser plugin factory

  - ### setPluginFactory

    public void setPluginFactory(ParserPluginFactory pluginFactory)
    Sets the parser plugin factory to use for source parsing.
    Parameters:
      `pluginFactory` - the parser plugin factory to use

  - ### setScriptExtensions

    public void setScriptExtensions(Set<String> scriptExtensions)
    Replaces the set of recognized script file extensions.
    Parameters:
      `scriptExtensions` - the script extensions to use

  - ### getScriptExtensions

    public Set<String> getScriptExtensions()
    Returns the recognized script file extensions.
    Returns:
      the configured script extensions

  - ### isClassTagPreemptionDisabled

    public boolean isClassTagPreemptionDisabled()
    Whether `@ClassTag` preemption is disabled globally under static compilation (GROOVY-12115). Preemption requires the API author's declared intent (`@ClassTag(preempt=true)`) and is contained to the declaring class; this flag lets the consuming build veto every preemptive upgrade anyway. Additive injection, such as for `asChecked`, is never gated by this flag. False (the default) honours declared intent.
    Returns:
      whether preemption is disabled
    Since:
      6.0.0

  - ### setClassTagPreemptionDisabled

    public void setClassTagPreemptionDisabled(boolean classTagPreemptionDisabled)
    Disables (or re-enables) `@ClassTag` preemption globally under static compilation (GROOVY-12115).
    Parameters:
      `classTagPreemptionDisabled` - whether to disable preemption
    Since:
      6.0.0

  - ### getDefaultScriptExtension

    public String getDefaultScriptExtension()
    Returns the default file extension used for generated scripts.
    Returns:
      the default script extension

  - ### setDefaultScriptExtension

    public void setDefaultScriptExtension(String defaultScriptExtension)
    Sets the default file extension used for generated scripts.
    Parameters:
      `defaultScriptExtension` - the default script extension

  - ### getRecompileGroovySource

    public boolean getRecompileGroovySource()
    Indicates whether Groovy sources should be recompiled when they change.
    Returns:
      `true` if recompilation is enabled

  - ### setRecompileGroovySource

    public void setRecompileGroovySource(boolean recompile)
    Sets whether changed Groovy sources should be recompiled.
    Parameters:
      `recompile` - `true` to enable recompilation checks

  - ### getMinimumRecompilationInterval

    public int getMinimumRecompilationInterval()
    Returns the minimum interval between recompilation checks.
    Returns:
      the recompilation interval in milliseconds

  - ### setMinimumRecompilationInterval

    public void setMinimumRecompilationInterval(int time)
    Sets the minimum interval between recompilation checks.
    Parameters:
      `time` - the recompilation interval in milliseconds

  - ### setTargetBytecode

    public void setTargetBytecode(String version)
    Sets the bytecode compatibility level. The parameter can take one of the values in `ALLOWED_JDKS`.
    Parameters:
      `version` - the bytecode compatibility level

  - ### getTargetBytecode

    public String getTargetBytecode()
    Retrieves the compiler bytecode compatibility level. Defaults to the minimum officially supported bytecode version for any particular Groovy version.
    Returns:
      bytecode compatibility level

  - ### getBytecodeVersion

    public final int getBytecodeVersion()
    Returns the targeted bytecode (aka Java class file) version number.
    Since:
      4.0.0

  - ### isPreviewFeatures

    public boolean isPreviewFeatures()
    Whether the bytecode version has preview features enabled (JEP 12)
    Returns:
      preview features

  - ### setPreviewFeatures

    public void setPreviewFeatures(boolean previewFeatures)
    Sets whether the bytecode version has preview features enabled (JEP 12).
    Parameters:
      `previewFeatures` - whether to support preview features

  - ### isLogClassgen

    public boolean isLogClassgen()
    Returns whether logging class generation is enabled
    Returns:
      whether logging class generation is enabled
    Since:
      4.0.0

  - ### setLogClassgen

    public void setLogClassgen(boolean logClassgen)
    Sets whether logging class generation is enabled
    Parameters:
      `logClassgen` - whether to enable logging class generation
    Since:
      4.0.0

  - ### getLogClassgenStackTraceMaxDepth

    public int getLogClassgenStackTraceMaxDepth()
    Returns stack trace max depth of logging class generation
    Returns:
      stack trace max depth of logging class generation
    Since:
      4.0.0

  - ### setLogClassgenStackTraceMaxDepth

    public void setLogClassgenStackTraceMaxDepth(int logClassgenStackTraceMaxDepth)
    Sets stack trace max depth of logging class generation
    Parameters:
      `logClassgenStackTraceMaxDepth` - stack trace max depth of logging class generation
    Since:
      4.0.0

  - ### getJointCompilationOptions

    public Map<String,Object> getJointCompilationOptions()
    Gets the joint compilation options for this configuration.
    Returns:
      the options

  - ### setJointCompilationOptions

    public void setJointCompilationOptions(Map<String,Object> options)
    Sets the joint compilation options for this configuration. Using null will disable joint compilation.
    Parameters:
      `options` - the options

  - ### getOptimizationOptions

    public Map<String,Boolean> getOptimizationOptions()
    Gets the optimization options for this configuration.
    Returns:
      the options (always not null)

  - ### setOptimizationOptions

    public void setOptimizationOptions(Map<String,Boolean> options)
    Sets the optimization options for this configuration. No entry or a true for that entry means to enable that optimization, a false means the optimization is disabled. Valid keys include `"all"`, `"int"`, `INVOKEDYNAMIC`, `PARALLEL_PARSE`, `GROOVYDOC`, and `RUNTIME_GROOVYDOC`. For-in per-iteration capture (GROOVY-11792) is not an optimization option; use `setForInPerIterationCaptureEnabled(boolean)` instead.
    Parameters:
      `options` - the options.
    Throws:
      `IllegalArgumentException` - if the options are null

  - ### addCompilationCustomizers

    public CompilerConfiguration addCompilationCustomizers(CompilationCustomizer... customizers)
    Adds compilation customizers to the compilation process. A compilation customizer is a class node operation which performs various operations going from adding imports to access control.
    Parameters:
      `customizers` - the list of customizers to be added
    Returns:
      this configuration instance

  - ### getCompilationCustomizers

    public List<CompilationCustomizer> getCompilationCustomizers()
    Returns the list of compilation customizers.
    Returns:
      the customizers (always not null)

  - ### getDisabledGlobalASTTransformations

    public Set<String> getDisabledGlobalASTTransformations()
    Returns the list of disabled global AST transformation class names.
    Returns:
      a list of global AST transformation fully qualified class names

  - ### setDisabledGlobalASTTransformations

    public void setDisabledGlobalASTTransformations(Set<String> disabledGlobalASTTransformations)
    Disables the specified global AST transformations. In order to avoid class loading side effects, it is not recommended to use MyASTTransformation.class.getName() but instead directly use the class name as a string. Disabled AST transformations only apply to automatically loaded global AST transformations, that is to say transformations defined in a META-INF/services/org.codehaus.groovy.transform.ASTTransformation file. If you explicitly add a global AST transformation in your compilation process, for example using the `ASTTransformationCustomizer` or using a `CompilationUnit.IPrimaryClassNodeOperation`, then nothing will prevent the transformation from being loaded.
    Parameters:
      `disabledGlobalASTTransformations` - a set of fully qualified class names of global AST transformations which should not be loaded.

  - ### getBytecodePostprocessor

    public BytecodeProcessor getBytecodePostprocessor()
    Returns the optional bytecode post-processor.
    Returns:
      the configured bytecode post-processor, or `null`

  - ### setBytecodePostprocessor

    public void setBytecodePostprocessor(BytecodeProcessor bytecodePostprocessor)
    Sets the bytecode post-processor applied to generated classes.
    Parameters:
      `bytecodePostprocessor` - the post-processor to use

  - ### isIndyEnabled

    public boolean isIndyEnabled()
    Checks if invoke dynamic is enabled. Enabled by default since Groovy 4.0. Can be disabled by setting the system property `groovy.target.indy` to `false` or by setting the `indy` optimization option to `false`. Disabling indy emits classic call-site bytecode that requires the optional `groovy-callsite` module on the compile and runtime classpaths (see GROOVY-11158). The ability to disable may be removed in a future version.

  - ### isGroovydocEnabled

    public boolean isGroovydocEnabled()
    Checks if groovydoc is enabled.

  - ### isRuntimeGroovydocEnabled

    public boolean isRuntimeGroovydocEnabled()
    Checks if runtime groovydoc is enabled.

  - ### isErrorRecoveryEnabled

    public boolean isErrorRecoveryEnabled()
    Checks if ANTLR parser error recovery is enabled.

    Disabled by default. Enable via `ERROR_RECOVERY` or the `groovy.parser.error.recovery` system property. Intended for IDE editing (multiple syntax diagnostics per pass). Leave off for production compilation: fail-fast is cheaper and avoids building partial trees.

    Returns:
      `true` if parser error recovery is enabled
    Since:
      5.0.0

  - ### isForInPerIterationCaptureEnabled

    public boolean isForInPerIterationCaptureEnabled()
    Checks if per-iteration capture of for-in (enhanced for-each) loop variables is enabled (GROOVY-11792). Classic `for` and `while` loops are not affected by this flag.

    This is a language-compatibility switch (not a performance optimization) and is independent of `getOptimizationOptions()`. Enabled by default. Disable via system property `groovy.forin.per.iteration.capture=false` or `setForInPerIterationCaptureEnabled(false)`, which restores the historical behaviour where a single shared `Reference` is updated across for-in iterations.

    Returns:
      `true` if each for-in iteration should allocate a fresh reference for loop variables shared with closures, lambdas, or anonymous inner classes
    See Also:
      - `setForInPerIterationCaptureEnabled(boolean)`

  - ### setForInPerIterationCaptureEnabled

    public void setForInPerIterationCaptureEnabled(boolean forInPerIterationCapture)
    Enables or disables per-iteration capture of for-in (enhanced for-each) loop variables shared with closures, lambdas, or anonymous inner classes (GROOVY-11792). Classic `for` and `while` loops are not affected. Default is `true`. Setting `false` restores the historical single shared `Reference` across iterations.
    Parameters:
      `forInPerIterationCapture` - `true` to allocate a fresh reference each for-in iteration for shared loop variables
    See Also:
      - `isForInPerIterationCaptureEnabled()`

  - ### getTargetPhase

    public int getTargetPhase()
    Gets the target compile phase: the last phase to be processed when `CompilationUnit.compile()` is called without an explicit phase. Defaults to `Phases.ALL`.
    Returns:
      the target phase number, one of the `Phases` constants
    Since:
      6.0.0
    See Also:
      - `setTargetPhase(int)`

  - ### setTargetPhase

    public void setTargetPhase(int targetPhase)
    Sets the target compile phase: the last phase to be processed when `CompilationUnit.compile()` is called without an explicit phase. Values outside the range of the `Phases` constants are clamped into range. Setting `Phases.CLASS_GENERATION` gives a check-only compilation, as used by the `groovyc --check` option. Callers that pass an explicit phase to `CompilationUnit.compile(int)`, such as the AST browser, are unaffected by this setting.
    Parameters:
      `targetPhase` - the target phase number, one of the `Phases` constants
    Since:
      6.0.0
    See Also:
      - `getTargetPhase()`

  - ### setTargetPhase

    public void setTargetPhase(CompilePhase targetPhase)
    Convenience overload of `setTargetPhase(int)` taking the `CompilePhase` enum, e.g. for configuration scripts: `configuration.targetPhase = CompilePhase.INSTRUCTION_SELECTION`.
    Parameters:
      `targetPhase` - the target phase
    Since:
      6.0.0

  - ### getErrorFormat

    public ErrorFormat getErrorFormat()
    Returns how compilation errors and warnings are rendered.
    Returns:
      the error format, never `null`
    Since:
      6.0.0
    See Also:
      - `setErrorFormat(ErrorFormat)`

  - ### setErrorFormat

    public void setErrorFormat(ErrorFormat errorFormat)
    Sets how compilation errors and warnings are rendered. `ErrorFormat.FULL`, the default, keeps the human-oriented rendering with the offending source line and a caret. `ErrorFormat.SHORT` emits one `file:line:column: severity: message` line per diagnostic, which suits editors, CI log parsers, and other tools (GROOVY-12312).
    Parameters:
      `errorFormat` - the error format; `null` selects the default
    Since:
      6.0.0