1 /* 2 * Copyright (c) 2015, 2017, 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.invoke.MethodType; 33 34 class StackFrameInfo implements StackFrame { 35 private final static JavaLangInvokeAccess JLIA = 36 SharedSecrets.getJavaLangInvokeAccess(); 37 38 // Footprint improvement: MemberName::clazz can replace 39 // StackFrameInfo::declaringClass. 40 41 private final boolean retainClassRef; 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.retainClassRef = walker.retainClassRef; 52 this.bci = -1; 53 this.memberName = JLIA.newMemberName(); 54 } 55 56 // package-private called by StackStreamFactory to skip 57 // the capability check 58 Class<?> declaringClass() { 59 return JLIA.getDeclaringClass(memberName); 60 } 61 62 // ----- implementation of StackFrame methods 63 64 @Override 65 public String getClassName() { 66 return declaringClass().getName(); 67 } 68 69 @Override 70 public Class<?> getDeclaringClass() { 71 ensureRetainClassRefEnabled(); 72 return declaringClass(); 73 } 74 75 @Override 76 public String getMethodName() { 77 return JLIA.getName(memberName); 78 } 79 80 @Override 81 public MethodType getMethodType() { 82 ensureRetainClassRefEnabled(); 83 return JLIA.getMethodType(memberName); 84 } 85 86 @Override 87 public String getDescriptor() { 88 return JLIA.getMethodDescriptor(memberName); 89 } 90 91 @Override 92 public int getByteCodeIndex() { 93 // bci not available for native methods 94 if (isNativeMethod()) 95 return -1; 96 97 return bci; 98 } 99 100 @Override 101 public String getFileName() { 102 return toStackTraceElement().getFileName(); 103 } 104 105 @Override 106 public int getLineNumber() { 107 // line number not available for native methods 108 if (isNativeMethod()) 109 return -2; 110 111 return toStackTraceElement().getLineNumber(); 112 } 113 114 115 @Override 116 public boolean isNativeMethod() { 117 return JLIA.isNative(memberName); 118 } 119 120 @Override 121 public String toString() { 122 return toStackTraceElement().toString(); 123 } 124 125 @Override 126 public StackTraceElement toStackTraceElement() { 127 StackTraceElement s = ste; 128 if (s == null) { 129 synchronized (this) { 130 s = ste; 131 if (s == null) { 132 ste = s = StackTraceElement.of(this); 133 } 134 } 135 } 136 return s; 137 } 138 139 private void ensureRetainClassRefEnabled() { 140 if (!retainClassRef) { 141 throw new UnsupportedOperationException("No access to RETAIN_CLASS_REFERENCE"); 142 } 143 } 144 }