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.lang.reflect.Module; 33 import java.util.Optional; 34 import java.util.OptionalInt; 35 36 class StackFrameInfo implements StackFrame { 37 private final static JavaLangInvokeAccess jlInvokeAccess = 38 SharedSecrets.getJavaLangInvokeAccess(); 39 40 // Footprint improvement: MemberName::clazz can replace 41 // StackFrameInfo::declaringClass. 42 43 final StackWalker walker; 44 final Class<?> declaringClass; 45 final Object memberName; 46 final short bci; 47 private volatile StackTraceElement ste; 48 49 /* 50 * Create StackFrameInfo for StackFrameTraverser and LiveStackFrameTraverser 51 * to use 52 */ 53 StackFrameInfo(StackWalker walker) { 54 this.walker = walker; 55 this.declaringClass = null; 56 this.bci = -1; 57 this.memberName = jlInvokeAccess.newMemberName(); 58 } 59 60 @Override 61 public String getClassName() { 62 return declaringClass.getName(); 63 } 64 65 @Override 66 public Class<?> getDeclaringClass() { 67 walker.ensureAccessEnabled(RETAIN_CLASS_REFERENCE); 68 return declaringClass; 69 } 70 71 @Override 72 public String getMethodName() { 73 return jlInvokeAccess.getName(memberName); 74 } 75 76 @Override 77 public final Optional<String> getFileName() { 78 StackTraceElement ste = toStackTraceElement(); 79 return ste.getFileName() != null ? Optional.of(ste.getFileName()) : Optional.empty(); 80 } 81 82 @Override 83 public final OptionalInt getLineNumber() { 84 StackTraceElement ste = toStackTraceElement(); 85 return ste.getLineNumber() > 0 ? OptionalInt.of(ste.getLineNumber()) : OptionalInt.empty(); 86 } 87 88 @Override 89 public final boolean isNativeMethod() { 90 StackTraceElement ste = toStackTraceElement(); 91 return ste.isNativeMethod(); 92 } 93 94 @Override 95 public String toString() { 96 StackTraceElement ste = toStackTraceElement(); 97 return ste.toString(); 98 } 99 100 /** 101 * Fill in the fields of the given StackTraceElement 102 */ 103 private native void toStackTraceElement0(StackTraceElement ste); 104 105 @Override 106 public StackTraceElement toStackTraceElement() { 107 StackTraceElement s = ste; 108 if (s == null) { 109 synchronized (this) { 110 s = ste; 111 if (s == null) { 112 s = new StackTraceElement(); 113 toStackTraceElement0(s); 114 ste = s; 115 } 116 } 117 } 118 return s; 119 } 120 }