src/jdk.jshell/share/classes/jdk/jshell/execution/DirectExecutionControl.java - platform/libcore - Git at Google

 /*
  * Copyright (c) 2016, 2018, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
  * under the terms of the GNU General Public License version 2 only, as
  * published by the Free Software Foundation.  Oracle designates this
  * particular file as subject to the "Classpath" exception as provided
  * by Oracle in the LICENSE file that accompanied this code.
  *
  * This code is distributed in the hope that it will be useful, but WITHOUT
  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  * version 2 for more details (a copy is included in the LICENSE file that
  * accompanied this code).
  *
  * You should have received a copy of the GNU General Public License version
  * 2 along with this work; if not, write to the Free Software Foundation,
  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  *
  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  * or visit www.oracle.com if you need additional information or have any
  * questions.
  */
 package jdk.jshell.execution;

 import java.lang.reflect.Array;
 import java.lang.reflect.Field;
 import java.lang.reflect.InvocationTargetException;
 import java.lang.reflect.Method;
 import java.util.stream.IntStream;
 import jdk.jshell.spi.ExecutionControl;
 import jdk.jshell.spi.SPIResolutionException;

 /**
  * An {@link ExecutionControl} implementation that runs in the current process.
  * May be used directly, or over a channel with
  * {@link Util#forwardExecutionControl(ExecutionControl, java.io.ObjectInput, java.io.ObjectOutput) }.
  *
  * @author Robert Field
  * @author Jan Lahoda
  * @since 9
  */
 public class DirectExecutionControl implements ExecutionControl {

     private static final String[] charRep;

     static {
         charRep = new String[256];
         for (int i = 0; i < charRep.length; ++i) {
             charRep[i] = Character.isISOControl(i)
                     ? String.format("\\%03o", i)
                     : "" + (char) i;
         }
         charRep['\b'] = "\\b";
         charRep['\t'] = "\\t";
         charRep['\n'] = "\\n";
         charRep['\f'] = "\\f";
         charRep['\r'] = "\\r";
         charRep['\\'] = "\\\\";
     }

     private final LoaderDelegate loaderDelegate;

     /**
      * Creates an instance, delegating loader operations to the specified
      * delegate.
      *
      * @param loaderDelegate the delegate to handle loading classes
      */
     public DirectExecutionControl(LoaderDelegate loaderDelegate) {
         this.loaderDelegate = loaderDelegate;
     }

     /**
      * Create an instance using the default class loading.
      */
     public DirectExecutionControl() {
         this(new DefaultLoaderDelegate());
     }

     @Override
     public void load(ClassBytecodes[] cbcs)
             throws ClassInstallException, NotImplementedException, EngineTerminationException {
         loaderDelegate.load(cbcs);
     }

     @Override
     public void redefine(ClassBytecodes[] cbcs)
             throws ClassInstallException, NotImplementedException, EngineTerminationException {
         throw new NotImplementedException("redefine not supported");
     }

     /**Notify that classes have been redefined.
      *
      * @param cbcs the class name and bytecodes to redefine
      * @throws NotImplementedException if not implemented
      * @throws EngineTerminationException the execution engine has terminated
      */
     protected void classesRedefined(ClassBytecodes[] cbcs)
             throws NotImplementedException, EngineTerminationException {
         loaderDelegate.classesRedefined(cbcs);
     }

     @Override
     public String invoke(String className, String methodName)
             throws RunException, InternalException, EngineTerminationException {
         Method doitMethod;
         try {
             Class<?> klass = findClass(className);
             doitMethod = klass.getDeclaredMethod(methodName, new Class<?>[0]);
             doitMethod.setAccessible(true);
         } catch (Throwable ex) {
             throw new InternalException(ex.toString());
         }

         try {
             clientCodeEnter();
             String result = invoke(doitMethod);
             System.out.flush();
             return result;
         } catch (RunException | InternalException | EngineTerminationException ex) {
             throw ex;
         } catch (SPIResolutionException ex) {
             return throwConvertedInvocationException(ex);
         } catch (InvocationTargetException ex) {
             return throwConvertedInvocationException(ex.getCause());
         } catch (Throwable ex) {
             return throwConvertedOtherException(ex);
         } finally {
             clientCodeLeave();
         }
     }

     @Override
     public String varValue(String className, String varName)
             throws RunException, EngineTerminationException, InternalException {
         Object val;
         try {
             Class<?> klass = findClass(className);
             Field var = klass.getDeclaredField(varName);
             var.setAccessible(true);
             val = var.get(null);
         } catch (Throwable ex) {
             throw new InternalException(ex.toString());
         }

         try {
             clientCodeEnter();
             return valueString(val);
         } catch (Throwable ex) {
             return throwConvertedInvocationException(ex);
         } finally {
             clientCodeLeave();
         }
     }

     @Override
     public void addToClasspath(String cp)
             throws EngineTerminationException, InternalException {
         loaderDelegate.addToClasspath(cp);
     }

     /**
      * {@inheritDoc}
      * <p>
      * Not supported.
      */
     @Override
     public void stop()
             throws EngineTerminationException, InternalException {
         throw new NotImplementedException("stop: Not supported.");
     }

     @Override
     public Object extensionCommand(String command, Object arg)
             throws RunException, EngineTerminationException, InternalException {
         throw new NotImplementedException("Unknown command: " + command);
     }

     @Override
     public void close() {
     }

     /**
      * Finds the class with the specified binary name.
      *
      * @param name the binary name of the class
      * @return the Class Object
      * @throws ClassNotFoundException if the class could not be found
      */
     protected Class<?> findClass(String name) throws ClassNotFoundException {
         return loaderDelegate.findClass(name);
     }

     /**
      * Invoke the specified "doit-method", a static method with no parameters.
      * The {@link DirectExecutionControl#invoke(java.lang.String, java.lang.String) }
      * in this class will call this to invoke.
      *
      * @param doitMethod the Method to invoke
      * @return the value or null
      * @throws Exception any exceptions thrown by
      * {@link java.lang.reflect.Method#invoke(Object, Object...) }
      * or any {@link ExecutionControl.ExecutionControlException}
      * to pass-through.
      */
     protected String invoke(Method doitMethod) throws Exception {
         Object res = doitMethod.invoke(null, new Object[0]);
         return valueString(res);
     }

     /**
      * Converts the {@code Object} value from
      * {@link ExecutionControl#invoke(String, String)  } or
      * {@link ExecutionControl#varValue(String, String)   } to {@code String}.
      *
      * @param value the value to convert
      * @return the {@code String} representation
      */
     protected static String valueString(Object value) {
         if (value == null) {
             return "null";
         } else if (value instanceof String) {
             return "\"" + ((String) value).codePoints()
                     .flatMap(cp ->
                         (cp == '"')
                             ? "\\\"".codePoints()
                             : (cp < 256)
                                 ? charRep[cp].codePoints()
                                 : IntStream.of(cp))
                     .collect(
                             StringBuilder::new,
                             StringBuilder::appendCodePoint,
                             StringBuilder::append)
                     .toString() + "\"";
         } else if (value instanceof Character) {
             char cp = (char) (Character) value;
             return "'" + (
                 (cp == '\'')
                     ? "\\\'"
                     : (cp < 256)
                             ? charRep[cp]
                             : String.valueOf(cp)) + "'";
         } else if (value.getClass().isArray()) {
             int dims = 0;
             Class<?> t = value.getClass();
             while (true) {
                 Class<?> ct = t.getComponentType();
                 if (ct == null) {
                     break;
                 }
                 ++dims;
                 t = ct;
             }
             String tn = t.getTypeName();
             int len = Array.getLength(value);
             StringBuilder sb = new StringBuilder();
             sb.append(tn.substring(tn.lastIndexOf('.') + 1, tn.length()));
             sb.append("[");
             sb.append(len);
             sb.append("]");
             for (int i = 1; i < dims; ++i) {
                 sb.append("[]");
             }
             sb.append(" { ");
             for (int i = 0; i < len; ++i) {
                 sb.append(valueString(Array.get(value, i)));
                 if (i < len - 1) {
                     sb.append(", ");
                 }
             }
             sb.append(" }");
             return sb.toString();
         } else {
             return value.toString();
         }
     }

     /**
      * Converts incoming exceptions in user code into instances of subtypes of
      * {@link ExecutionControl.ExecutionControlException} and throws the
      * converted exception.
      *
      * @param cause the exception to convert
      * @return never returns as it always throws
      * @throws ExecutionControl.RunException for normal exception occurrences
      * @throws ExecutionControl.InternalException for internal problems
      */
     protected String throwConvertedInvocationException(Throwable cause) throws RunException, InternalException {
         throw asRunException(cause);
     }

     private RunException asRunException(Throwable ex) {
         if (ex instanceof SPIResolutionException) {
             SPIResolutionException spire = (SPIResolutionException) ex;
             return new ResolutionException(spire.id(), spire.getStackTrace());
         } else {
             UserException ue = new UserException(ex.getMessage(),
                     ex.getClass().getName(),
                     ex.getStackTrace());
             Throwable cause = ex.getCause();
             ue.initCause(cause == null ? null : asRunException(cause));
             return ue;
         }
     }

     /**
      * Converts incoming exceptions in agent code into instances of subtypes of
      * {@link ExecutionControl.ExecutionControlException} and throws the
      * converted exception.
      *
      * @param ex the exception to convert
      * @return never returns as it always throws
      * @throws ExecutionControl.RunException for normal exception occurrences
      * @throws ExecutionControl.InternalException for internal problems
      */
     protected String throwConvertedOtherException(Throwable ex) throws RunException, InternalException {
         throw new InternalException(ex.toString());
     }

     /**
      * Marks entry into user code.
      *
      * @throws ExecutionControl.InternalException in unexpected failure cases
      */
     protected void clientCodeEnter() throws InternalException {
     }

     /**
      * Marks departure from user code.
      *
      * @throws ExecutionControl.InternalException in unexpected failure cases
      */
     protected void clientCodeLeave() throws InternalException {
     }

 }
	/*
	* Copyright (c) 2016, 2018, Oracle and/or its affiliates. All rights reserved.
	* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
	*
	* This code is free software; you can redistribute it and/or modify it
	* under the terms of the GNU General Public License version 2 only, as
	* published by the Free Software Foundation. Oracle designates this
	* particular file as subject to the "Classpath" exception as provided
	* by Oracle in the LICENSE file that accompanied this code.
	*
	* This code is distributed in the hope that it will be useful, but WITHOUT
	* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
	* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
	* version 2 for more details (a copy is included in the LICENSE file that
	* accompanied this code).
	*
	* You should have received a copy of the GNU General Public License version
	* 2 along with this work; if not, write to the Free Software Foundation,
	* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
	*
	* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
	* or visit www.oracle.com if you need additional information or have any
	* questions.
	*/
	package jdk.jshell.execution;

	import java.lang.reflect.Array;
	import java.lang.reflect.Field;
	import java.lang.reflect.InvocationTargetException;
	import java.lang.reflect.Method;
	import java.util.stream.IntStream;
	import jdk.jshell.spi.ExecutionControl;
	import jdk.jshell.spi.SPIResolutionException;

	/**
	* An {@link ExecutionControl} implementation that runs in the current process.
	* May be used directly, or over a channel with
	* {@link Util#forwardExecutionControl(ExecutionControl, java.io.ObjectInput, java.io.ObjectOutput) }.
	*
	* @author Robert Field
	* @author Jan Lahoda
	* @since 9
	*/
	public class DirectExecutionControl implements ExecutionControl {

	private static final String[] charRep;

	static {
	charRep = new String[256];
	for (int i = 0; i < charRep.length; ++i) {
	charRep[i] = Character.isISOControl(i)
	? String.format("\\%03o", i)
	: "" + (char) i;
	}
	charRep['\b'] = "\\b";
	charRep['\t'] = "\\t";
	charRep['\n'] = "\\n";
	charRep['\f'] = "\\f";
	charRep['\r'] = "\\r";
	charRep['\\'] = "\\\\";
	}

	private final LoaderDelegate loaderDelegate;

	/**
	* Creates an instance, delegating loader operations to the specified
	* delegate.
	*
	* @param loaderDelegate the delegate to handle loading classes
	*/
	public DirectExecutionControl(LoaderDelegate loaderDelegate) {
	this.loaderDelegate = loaderDelegate;
	}

	/**
	* Create an instance using the default class loading.
	*/
	public DirectExecutionControl() {
	this(new DefaultLoaderDelegate());
	}

	@Override
	public void load(ClassBytecodes[] cbcs)
	throws ClassInstallException, NotImplementedException, EngineTerminationException {
	loaderDelegate.load(cbcs);
	}

	@Override
	public void redefine(ClassBytecodes[] cbcs)
	throws ClassInstallException, NotImplementedException, EngineTerminationException {
	throw new NotImplementedException("redefine not supported");
	}

	/**Notify that classes have been redefined.
	*
	* @param cbcs the class name and bytecodes to redefine
	* @throws NotImplementedException if not implemented
	* @throws EngineTerminationException the execution engine has terminated
	*/
	protected void classesRedefined(ClassBytecodes[] cbcs)
	throws NotImplementedException, EngineTerminationException {
	loaderDelegate.classesRedefined(cbcs);
	}

	@Override
	public String invoke(String className, String methodName)
	throws RunException, InternalException, EngineTerminationException {
	Method doitMethod;
	try {
	Class<?> klass = findClass(className);
	doitMethod = klass.getDeclaredMethod(methodName, new Class<?>[0]);
	doitMethod.setAccessible(true);
	} catch (Throwable ex) {
	throw new InternalException(ex.toString());
	}

	try {
	clientCodeEnter();
	String result = invoke(doitMethod);
	System.out.flush();
	return result;
	} catch (RunException \| InternalException \| EngineTerminationException ex) {
	throw ex;
	} catch (SPIResolutionException ex) {
	return throwConvertedInvocationException(ex);
	} catch (InvocationTargetException ex) {
	return throwConvertedInvocationException(ex.getCause());
	} catch (Throwable ex) {
	return throwConvertedOtherException(ex);
	} finally {
	clientCodeLeave();
	}
	}

	@Override
	public String varValue(String className, String varName)
	throws RunException, EngineTerminationException, InternalException {
	Object val;
	try {
	Class<?> klass = findClass(className);
	Field var = klass.getDeclaredField(varName);
	var.setAccessible(true);
	val = var.get(null);
	} catch (Throwable ex) {
	throw new InternalException(ex.toString());
	}

	try {
	clientCodeEnter();
	return valueString(val);
	} catch (Throwable ex) {
	return throwConvertedInvocationException(ex);
	} finally {
	clientCodeLeave();
	}
	}

	@Override
	public void addToClasspath(String cp)
	throws EngineTerminationException, InternalException {
	loaderDelegate.addToClasspath(cp);
	}

	/**
	* {@inheritDoc}
	* <p>
	* Not supported.
	*/
	@Override
	public void stop()
	throws EngineTerminationException, InternalException {
	throw new NotImplementedException("stop: Not supported.");
	}

	@Override
	public Object extensionCommand(String command, Object arg)
	throws RunException, EngineTerminationException, InternalException {
	throw new NotImplementedException("Unknown command: " + command);
	}

	@Override
	public void close() {
	}

	/**
	* Finds the class with the specified binary name.
	*
	* @param name the binary name of the class
	* @return the Class Object
	* @throws ClassNotFoundException if the class could not be found
	*/
	protected Class<?> findClass(String name) throws ClassNotFoundException {
	return loaderDelegate.findClass(name);
	}

	/**
	* Invoke the specified "doit-method", a static method with no parameters.
	* The {@link DirectExecutionControl#invoke(java.lang.String, java.lang.String) }
	* in this class will call this to invoke.
	*
	* @param doitMethod the Method to invoke
	* @return the value or null
	* @throws Exception any exceptions thrown by
	* {@link java.lang.reflect.Method#invoke(Object, Object...) }
	* or any {@link ExecutionControl.ExecutionControlException}
	* to pass-through.
	*/
	protected String invoke(Method doitMethod) throws Exception {
	Object res = doitMethod.invoke(null, new Object[0]);
	return valueString(res);
	}

	/**
	* Converts the {@code Object} value from
	* {@link ExecutionControl#invoke(String, String) } or
	* {@link ExecutionControl#varValue(String, String) } to {@code String}.
	*
	* @param value the value to convert
	* @return the {@code String} representation
	*/
	protected static String valueString(Object value) {
	if (value == null) {
	return "null";
	} else if (value instanceof String) {
	return "\"" + ((String) value).codePoints()
	.flatMap(cp ->
	(cp == '"')
	? "\\\"".codePoints()
	: (cp < 256)
	? charRep[cp].codePoints()
	: IntStream.of(cp))
	.collect(
	StringBuilder::new,
	StringBuilder::appendCodePoint,
	StringBuilder::append)
	.toString() + "\"";
	} else if (value instanceof Character) {
	char cp = (char) (Character) value;
	return "'" + (
	(cp == '\'')
	? "\\\'"
	: (cp < 256)
	? charRep[cp]
	: String.valueOf(cp)) + "'";
	} else if (value.getClass().isArray()) {
	int dims = 0;
	Class<?> t = value.getClass();
	while (true) {
	Class<?> ct = t.getComponentType();
	if (ct == null) {
	break;
	}
	++dims;
	t = ct;
	}
	String tn = t.getTypeName();
	int len = Array.getLength(value);
	StringBuilder sb = new StringBuilder();
	sb.append(tn.substring(tn.lastIndexOf('.') + 1, tn.length()));
	sb.append("[");
	sb.append(len);
	sb.append("]");
	for (int i = 1; i < dims; ++i) {
	sb.append("[]");
	}
	sb.append(" { ");
	for (int i = 0; i < len; ++i) {
	sb.append(valueString(Array.get(value, i)));
	if (i < len - 1) {
	sb.append(", ");
	}
	}
	sb.append(" }");
	return sb.toString();
	} else {
	return value.toString();
	}
	}

	/**
	* Converts incoming exceptions in user code into instances of subtypes of
	* {@link ExecutionControl.ExecutionControlException} and throws the
	* converted exception.
	*
	* @param cause the exception to convert
	* @return never returns as it always throws
	* @throws ExecutionControl.RunException for normal exception occurrences
	* @throws ExecutionControl.InternalException for internal problems
	*/
	protected String throwConvertedInvocationException(Throwable cause) throws RunException, InternalException {
	throw asRunException(cause);
	}

	private RunException asRunException(Throwable ex) {
	if (ex instanceof SPIResolutionException) {
	SPIResolutionException spire = (SPIResolutionException) ex;
	return new ResolutionException(spire.id(), spire.getStackTrace());
	} else {
	UserException ue = new UserException(ex.getMessage(),
	ex.getClass().getName(),
	ex.getStackTrace());
	Throwable cause = ex.getCause();
	ue.initCause(cause == null ? null : asRunException(cause));
	return ue;
	}
	}

	/**
	* Converts incoming exceptions in agent code into instances of subtypes of
	* {@link ExecutionControl.ExecutionControlException} and throws the
	* converted exception.
	*
	* @param ex the exception to convert
	* @return never returns as it always throws
	* @throws ExecutionControl.RunException for normal exception occurrences
	* @throws ExecutionControl.InternalException for internal problems
	*/
	protected String throwConvertedOtherException(Throwable ex) throws RunException, InternalException {
	throw new InternalException(ex.toString());
	}

	/**
	* Marks entry into user code.
	*
	* @throws ExecutionControl.InternalException in unexpected failure cases
	*/
	protected void clientCodeEnter() throws InternalException {
	}

	/**
	* Marks departure from user code.
	*
	* @throws ExecutionControl.InternalException in unexpected failure cases
	*/
	protected void clientCodeLeave() throws InternalException {
	}

	}