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Diffstat (limited to 'src/jdk/nashorn/internal/ir/JumpStatement.java')
-rw-r--r-- | src/jdk/nashorn/internal/ir/JumpStatement.java | 120 |
1 files changed, 120 insertions, 0 deletions
diff --git a/src/jdk/nashorn/internal/ir/JumpStatement.java b/src/jdk/nashorn/internal/ir/JumpStatement.java new file mode 100644 index 00000000..07707171 --- /dev/null +++ b/src/jdk/nashorn/internal/ir/JumpStatement.java @@ -0,0 +1,120 @@ +/* + * Copyright (c) 2010, 2013, 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.nashorn.internal.ir; + +import jdk.nashorn.internal.codegen.Label; + +/** + * Common base class for jump statements (e.g. {@code break} and {@code continue}). + */ +public abstract class JumpStatement extends Statement implements JoinPredecessor { + private static final long serialVersionUID = 1L; + + private final String labelName; + private final LocalVariableConversion conversion; + + /** + * Constructor + * + * @param lineNumber line number + * @param token token + * @param finish finish + * @param labelName label name for break or null if none + */ + protected JumpStatement(final int lineNumber, final long token, final int finish, final String labelName) { + super(lineNumber, token, finish); + this.labelName = labelName; + this.conversion = null; + } + + /** + * Copy constructor. + * @param jumpStatement the original jump statement. + * @param conversion a new local variable conversion. + */ + protected JumpStatement(final JumpStatement jumpStatement, final LocalVariableConversion conversion) { + super(jumpStatement); + this.labelName = jumpStatement.labelName; + this.conversion = conversion; + } + + @Override + public boolean hasGoto() { + return true; + } + + /** + * Get the label name for this break node + * @return label name, or null if none + */ + public String getLabelName() { + return labelName; + } + + @Override + public void toString(final StringBuilder sb, final boolean printType) { + sb.append(getStatementName()); + + if (labelName != null) { + sb.append(' ').append(labelName); + } + } + + abstract String getStatementName(); + + /** + * Finds the target for this jump statement in a lexical context. + * @param lc the lexical context + * @return the target, or null if not found + */ + public abstract BreakableNode getTarget(final LexicalContext lc); + + /** + * Returns the label corresponding to this kind of jump statement (either a break or continue label) in the target. + * @param target the target. Note that it need not be the target of this jump statement, as the method can retrieve + * a label on any passed target as long as the target has a label of the requisite kind. Of course, it is advisable + * to invoke the method on a jump statement that targets the breakable. + * @return the label of the target corresponding to the kind of jump statement. + * @throws ClassCastException if invoked on the kind of breakable node that this jump statement is not prepared to + * handle. + */ + public abstract Label getTargetLabel(final BreakableNode target); + + @Override + public JumpStatement setLocalVariableConversion(final LexicalContext lc, final LocalVariableConversion conversion) { + if(this.conversion == conversion) { + return this; + } + return createNewJumpStatement(conversion); + } + + abstract JumpStatement createNewJumpStatement(LocalVariableConversion newConversion); + + @Override + public LocalVariableConversion getLocalVariableConversion() { + return conversion; + } +} |