JVM Lifecycle Management

def startJVM(*jvmargs: str, jvmpath=None, classpath=None, ignoreUnrecognized=False, convertStrings=False, interrupt=True):
    """Start the Java Virtual Machine.
    
    Args:
        *jvmargs: JVM arguments like "-Xmx1g", "-Djava.awt.headless=true"
        jvmpath: Path to JVM library file (libjvm.so, jvm.dll, etc.)
        classpath: String path or list of paths to set classpath
        ignoreUnrecognized: Ignore invalid JVM arguments (default False)
        convertStrings: Force Java strings to convert to Python str (default False)
        interrupt: Enable interrupt handling (default True)
    
    Raises:
        OSError: If JVM cannot be started
        RuntimeError: If JVM is already running
    """

def shutdownJVM():
    """Shutdown the running JVM.
    
    Raises:
        RuntimeError: If JVM is not running
    """

def isJVMStarted() -> bool:
    """Check if JVM is currently running.
    
    Returns:
        bool: True if JVM is started, False otherwise
    """

def getDefaultJVMPath() -> str:
    """Find the default JVM library path on the system.
    
    Returns:
        str: Path to the default JVM library
        
    Raises:
        JVMNotFoundException: If no JVM is found
    """

def get_default_jvm_path() -> str:
    """Alternative name for getDefaultJVMPath().
    
    Returns:
        str: Path to the default JVM library
    """

def getJVMVersion() -> tuple:
    """Get the version of the running JVM.
    
    Returns:
        tuple: JVM version as (major, minor, patch)
        
    Raises:
        RuntimeError: If JVM is not running
    """

def isThreadAttachedToJVM() -> bool:
    """Check if current thread is attached to JVM.
    
    Returns:
        bool: True if thread is attached
        
    Note:
        Deprecated: JPype automatically manages thread attachment
    """

def attachThreadToJVM():
    """Manually attach current thread to JVM.
    
    Note:
        Deprecated: JPype automatically manages thread attachment
    """

def detachThreadFromJVM():
    """Detach current thread from JVM.
    
    Note:
        Deprecated: JPype automatically manages thread attachment
    """

def onJVMStart(func):
    """Decorator to register function to be called after JVM starts.
    
    Args:
        func: Function to call when JVM starts
        
    Returns:
        func: The original function (for use as decorator)
        
    Example:
        @onJVMStart
        def load_resources():
            # Load Java classes or resources
            pass
    """

class JVMNotFoundException(RuntimeError):
    """Raised when JVM installation cannot be found."""

class JVMNotSupportedException(RuntimeError):
    """Raised when JVM version is not supported."""

class JVMNotRunning(RuntimeError):
    """Raised when JVM operations attempted while not running."""

import jpype

# Start JVM with default settings
jpype.startJVM()

# Check if running
if jpype.isJVMStarted():
    print("JVM is running")

# Get JVM version
version = jpype.getJVMVersion()
print(f"JVM version: {version}")

# Shutdown when done
jpype.shutdownJVM()

import jpype

# Start with custom memory and system properties
jpype.startJVM(
    jpype.getDefaultJVMPath(),
    "-Xmx2g",  # Set max heap to 2GB
    "-Xms512m",  # Set initial heap to 512MB
    "-Djava.awt.headless=true",  # Headless mode
    classpath=["lib/mylib.jar", "classes/"],
    convertStrings=False  # Keep Java strings as JString objects
)

# Your Java integration code here
java = jpype.java
String = java.lang.String("Hello Java!")

jpype.shutdownJVM()

import jpype

@jpype.onJVMStart
def initialize_resources():
    """Load resources after JVM starts."""
    # Load Java classes that depend on JVM
    MyClass = jpype.JClass("com.example.MyClass")
    MyClass.initializeStaticResources()

# Start JVM - callback will be executed automatically
jpype.startJVM()
jpype.shutdownJVM()

import jpype

try:
    jvm_path = jpype.getDefaultJVMPath()
    print(f"Found JVM at: {jvm_path}")
    jpype.startJVM(jvm_path)
except jpype.JVMNotFoundException:
    print("No JVM found on system")
except jpype.JVMNotSupportedException:
    print("JVM version not supported")