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* Copyright (c) 2010, 2016, 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
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package jdk.nashorn.api.scripting;
import java.util.ArrayList;
import java.util.List;
import jdk.nashorn.internal.codegen.CompilerConstants;
import jdk.nashorn.internal.runtime.ECMAErrors;
import jdk.nashorn.internal.runtime.ScriptObject;
/**
* This is base exception for all Nashorn exceptions. These originate from
* user's ECMAScript code. Example: script parse errors, exceptions thrown from
* scripts. Note that ScriptEngine methods like "eval", "invokeMethod",
* "invokeFunction" will wrap this as ScriptException and throw it. But, there
* are cases where user may need to access this exception (or implementation
* defined subtype of this). For example, if java interface is implemented by a
* script object or Java access to script object properties via java.util.Map
* interface. In these cases, user code will get an instance of this or
* implementation defined subclass.
*
* @since 1.8u40
*/
@SuppressWarnings("serial")
public abstract class NashornException extends RuntimeException {
private static final long serialVersionUID = 1L;
// script file name
private String fileName;
// script line number
private int line;
// are the line and fileName unknown?
private boolean lineAndFileNameUnknown;
// script column number
private int column;
// underlying ECMA error object - lazily initialized
private Object ecmaError;
/**
* Constructor to initialize error message, file name, line and column numbers.
*
* @param msg exception message
* @param fileName file name
* @param line line number
* @param column column number
*/
protected NashornException(final String msg, final String fileName, final int line, final int column) {
this(msg, null, fileName, line, column);
}
/**
* Constructor to initialize error message, cause exception, file name, line and column numbers.
*
* @param msg exception message
* @param cause exception cause
* @param fileName file name
* @param line line number
* @param column column number
*/
protected NashornException(final String msg, final Throwable cause, final String fileName, final int line, final int column) {
super(msg, cause == null ? null : cause);
this.fileName = fileName;
this.line = line;
this.column = column;
}
/**
* Constructor to initialize error message and cause exception.
*
* @param msg exception message
* @param cause exception cause
*/
protected NashornException(final String msg, final Throwable cause) {
super(msg, cause == null ? null : cause);
// Hard luck - no column number info
this.column = -1;
// We can retrieve the line number and file name from the stack trace if needed
this.lineAndFileNameUnknown = true;
}
/**
* Get the source file name for this {@code NashornException}
*
* @return the file name
*/
public final String getFileName() {
ensureLineAndFileName();
return fileName;
}
/**
* Set the source file name for this {@code NashornException}
*
* @param fileName the file name
*/
public final void setFileName(final String fileName) {
this.fileName = fileName;
lineAndFileNameUnknown = false;
}
/**
* Get the line number for this {@code NashornException}
*
* @return the line number
*/
public final int getLineNumber() {
ensureLineAndFileName();
return line;
}
/**
* Set the line number for this {@code NashornException}
*
* @param line the line number
*/
public final void setLineNumber(final int line) {
lineAndFileNameUnknown = false;
this.line = line;
}
/**
* Get the column for this {@code NashornException}
*
* @return the column number
*/
public final int getColumnNumber() {
return column;
}
/**
* Set the column for this {@code NashornException}
*
* @param column the column number
*/
public final void setColumnNumber(final int column) {
this.column = column;
}
/**
* Returns array javascript stack frames from the given exception object.
*
* @param exception exception from which stack frames are retrieved and filtered
* @return array of javascript stack frames
*/
public static StackTraceElement[] getScriptFrames(final Throwable exception) {
final StackTraceElement[] frames = exception.getStackTrace();
final List<StackTraceElement> filtered = new ArrayList<>();
for (final StackTraceElement st : frames) {
if (ECMAErrors.isScriptFrame(st)) {
final String className = "<" + st.getFileName() + ">";
String methodName = st.getMethodName();
if (methodName.equals(CompilerConstants.PROGRAM.symbolName())) {
methodName = "<program>";
} else {
methodName = stripMethodName(methodName);
}
filtered.add(new StackTraceElement(className, methodName,
st.getFileName(), st.getLineNumber()));
}
}
return filtered.toArray(new StackTraceElement[0]);
}
private static String stripMethodName(final String methodName) {
String name = methodName;
final int nestedSeparator = name.lastIndexOf(CompilerConstants.NESTED_FUNCTION_SEPARATOR.symbolName());
if (nestedSeparator >= 0) {
name = name.substring(nestedSeparator + 1);
}
final int idSeparator = name.indexOf(CompilerConstants.ID_FUNCTION_SEPARATOR.symbolName());
if (idSeparator >= 0) {
name = name.substring(0, idSeparator);
}
return name.contains(CompilerConstants.ANON_FUNCTION_PREFIX.symbolName()) ? "<anonymous>" : name;
}
/**
* Return a formatted script stack trace string with frames information separated by '\n'
*
* @param exception exception for which script stack string is returned
* @return formatted stack trace string
*/
public static String getScriptStackString(final Throwable exception) {
final StringBuilder buf = new StringBuilder();
final StackTraceElement[] frames = getScriptFrames(exception);
for (final StackTraceElement st : frames) {
buf.append("\tat ");
buf.append(st.getMethodName());
buf.append(" (");
buf.append(st.getFileName());
buf.append(':');
buf.append(st.getLineNumber());
buf.append(")\n");
}
final int len = buf.length();
// remove trailing '\n'
if (len > 0) {
assert buf.charAt(len - 1) == '\n';
buf.deleteCharAt(len - 1);
}
return buf.toString();
}
/**
* Get the thrown object. Subclass responsibility
* @return thrown object
*/
protected Object getThrown() {
return null;
}
/**
* Initialization function for ECMA errors. Stores the error
* in the ecmaError field of this class. It is only initialized
* once, and then reused
*
* @param global the global
* @return initialized exception
*/
NashornException initEcmaError(final ScriptObject global) {
if (ecmaError != null) {
return this; // initialized already!
}
final Object thrown = getThrown();
if (thrown instanceof ScriptObject) {
setEcmaError(ScriptObjectMirror.wrap(thrown, global));
} else {
setEcmaError(thrown);
}
return this;
}
/**
* Return the underlying ECMA error object, if available.
*
* @return underlying ECMA Error object's mirror or whatever was thrown
* from script such as a String, Number or a Boolean.
*/
public Object getEcmaError() {
return ecmaError;
}
/**
* Return the underlying ECMA error object, if available.
*
* @param ecmaError underlying ECMA Error object's mirror or whatever was thrown
* from script such as a String, Number or a Boolean.
*/
public void setEcmaError(final Object ecmaError) {
this.ecmaError = ecmaError;
}
private void ensureLineAndFileName() {
if (lineAndFileNameUnknown) {
for (final StackTraceElement ste : getStackTrace()) {
if (ECMAErrors.isScriptFrame(ste)) {
// Whatever here is compiled from JavaScript code
fileName = ste.getFileName();
line = ste.getLineNumber();
return;
}
}
lineAndFileNameUnknown = false;
}
}
}