1 /* 2 * Copyright (c) 2015, 2016, 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 33 class StackFrameInfo implements StackFrame { 34 private final static JavaLangInvokeAccess JLIA = 35 SharedSecrets.getJavaLangInvokeAccess(); 36 37 // Footprint improvement: MemberName::clazz can replace 38 // StackFrameInfo::declaringClass. 39 40 private final StackWalker walker; 41 private final Class<?> declaringClass; 42 private final Object memberName; 43 private final short bci; 44 private volatile StackTraceElement ste; 45 46 /* 47 * Create StackFrameInfo for StackFrameTraverser and LiveStackFrameTraverser 48 * to use 49 */ 50 StackFrameInfo(StackWalker walker) { 51 this.walker = walker; 52 this.declaringClass = null; 53 this.bci = -1; 54 this.memberName = JLIA.newMemberName(); 55 } 56 57 // package-private called by StackStreamFactory to skip 58 // the capability check 59 Class<?> declaringClass() { 60 return declaringClass; 61 } 62 63 // ----- implementation of StackFrame methods 64 65 @Override 66 public String getClassName() { 67 return declaringClass.getName(); 68 } 69 70 @Override 71 public Class<?> getDeclaringClass() { 72 walker.ensureAccessEnabled(RETAIN_CLASS_REFERENCE); 73 return declaringClass; 74 } 75 76 @Override 77 public String getMethodName() { 78 return JLIA.getName(memberName); 79 } 80 81 @Override 82 public int getByteCodeIndex() { 83 // bci not available for native methods 84 if (isNativeMethod()) 85 return -1; 86 87 return bci; 88 } 89 90 @Override 91 public String getFileName() { 92 return toStackTraceElement().getFileName(); 93 } 94 95 @Override 96 public int getLineNumber() { 97 // line number not available for native methods 98 if (isNativeMethod()) 99 return -2; 100 101 return toStackTraceElement().getLineNumber(); 102 } 103 104 105 @Override 106 public boolean isNativeMethod() { 107 return JLIA.isNative(memberName); 108 } 109 110 @Override 111 public String toString() { 112 return toStackTraceElement().toString(); 113 } 114 115 /** 116 * Fill in the fields of the given StackTraceElement 117 */ 118 private native void toStackTraceElement0(StackTraceElement ste); 119 120 @Override 121 public StackTraceElement toStackTraceElement() { 122 StackTraceElement s = ste; 123 if (s == null) { 124 synchronized (this) { 125 s = ste; 126 if (s == null) { 127 s = new StackTraceElement(); 128 toStackTraceElement0(s); 129 ste = s; 130 } 131 } 132 } 133 return s; 134 } 135 }