1 /* 2 * Copyright (c) 2015, Oracle and/or its affiliates. All rights reserved. 3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. 4 * 5 * This code is free software; you can redistribute it and/or modify it 6 * under the terms of the GNU General Public License version 2 only, as 7 * published by the Free Software Foundation. Oracle designates this 8 * particular file as subject to the "Classpath" exception as provided 9 * by Oracle in the LICENSE file that accompanied this code. 10 * 11 * This code is distributed in the hope that it will be useful, but WITHOUT 12 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 13 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 14 * version 2 for more details (a copy is included in the LICENSE file that 15 * accompanied this code). 16 * 17 * You should have received a copy of the GNU General Public License version 18 * 2 along with this work; if not, write to the Free Software Foundation, 19 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 20 * 21 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 22 * or visit www.oracle.com if you need additional information or have any 23 * questions. 24 */ 25 package java.lang; 26 27 import jdk.internal.misc.JavaLangInvokeAccess; 28 import jdk.internal.misc.SharedSecrets; 29 30 import static java.lang.StackWalker.Option.*; 31 import java.lang.StackWalker.StackFrame; 32 import java.util.Optional; 33 import java.util.OptionalInt; 34 35 class StackFrameInfo implements StackFrame { 36 private final static JavaLangInvokeAccess JLIA = 37 SharedSecrets.getJavaLangInvokeAccess(); 38 39 // Footprint improvement: MemberName::clazz can replace 40 // StackFrameInfo::declaringClass. 41 42 final StackWalker walker; 43 final Class<?> declaringClass; 44 final Object memberName; 45 final short bci; 46 private volatile StackTraceElement ste; 47 48 /* 49 * Create StackFrameInfo for StackFrameTraverser and LiveStackFrameTraverser 50 * to use 51 */ 52 StackFrameInfo(StackWalker walker) { 53 this.walker = walker; 54 this.declaringClass = null; 55 this.bci = -1; 56 this.memberName = JLIA.newMemberName(); 57 } 58 59 @Override 60 public String getClassName() { 61 return declaringClass.getName(); 62 } 63 64 @Override 65 public Class<?> getDeclaringClass() { 66 walker.ensureAccessEnabled(RETAIN_CLASS_REFERENCE); 67 return declaringClass; 68 } 69 70 @Override 71 public String getMethodName() { 72 return JLIA.getName(memberName); 73 } 74 75 @Override 76 public int getByteCodeIndex() { 77 return bci; 78 } 79 80 @Override 81 public final String getFileName() { 82 if (isNativeMethod()) 83 return null; 84 85 return toStackTraceElement().getFileName(); 86 } 87 88 @Override 89 public final int getLineNumber() { 90 if (isNativeMethod()) 91 return -2; 92 93 return toStackTraceElement().getLineNumber(); 94 } 95 96 97 @Override 98 public final boolean isNativeMethod() { 99 return JLIA.isNative(memberName); 100 } 101 102 @Override 103 public String toString() { 104 return toStackTraceElement().toString(); 105 } 106 107 /** 108 * Fill in the fields of the given StackTraceElement 109 */ 110 private native void toStackTraceElement0(StackTraceElement ste); 111 112 @Override 113 public StackTraceElement toStackTraceElement() { 114 StackTraceElement s = ste; 115 if (s == null) { 116 synchronized (this) { 117 s = ste; 118 if (s == null) { 119 s = new StackTraceElement(); 120 toStackTraceElement0(s); 121 ste = s; 122 } 123 } 124 } 125 return s; 126 } 127 }