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Diffstat (limited to 'src/utils/lombok/bytecode/ClassFileMetaData.java')
| -rw-r--r-- | src/utils/lombok/bytecode/ClassFileMetaData.java | 453 |
1 files changed, 453 insertions, 0 deletions
diff --git a/src/utils/lombok/bytecode/ClassFileMetaData.java b/src/utils/lombok/bytecode/ClassFileMetaData.java new file mode 100644 index 00000000..b1e0eff3 --- /dev/null +++ b/src/utils/lombok/bytecode/ClassFileMetaData.java @@ -0,0 +1,453 @@ +/* + * Copyright © 2010 Reinier Zwitserloot and Roel Spilker. + * + * Permission is hereby granted, free of charge, to any person obtaining a copy + * of this software and associated documentation files (the "Software"), to deal + * in the Software without restriction, including without limitation the rights + * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell + * copies of the Software, and to permit persons to whom the Software is + * furnished to do so, subject to the following conditions: + * + * The above copyright notice and this permission notice shall be included in + * all copies or substantial portions of the Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR + * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, + * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE + * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER + * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, + * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN + * THE SOFTWARE. + */ +package lombok.bytecode; + +import java.util.ArrayList; +import java.util.Collections; +import java.util.List; + +/** + * Utility to read the constant pool, header, and inheritance information of any class file. + */ +public class ClassFileMetaData { + private static final byte UTF8 = 1; + private static final byte INTEGER = 3; + private static final byte FLOAT = 4; + private static final byte LONG = 5; + private static final byte DOUBLE = 6; + private static final byte CLASS = 7; + private static final byte STRING = 8; + private static final byte FIELD = 9; + private static final byte METHOD = 10; + private static final byte INTERFACE_METHOD = 11; + private static final byte NAME_TYPE = 12; + // New in java7: support for methodhandles and invokedynamic + private static final byte METHOD_HANDLE = 15; + private static final byte METHOD_TYPE = 16; + private static final byte INVOKE_DYNAMIC = 18; + + private static final int NOT_FOUND = -1; + private static final int START_OF_CONSTANT_POOL = 8; + + private final byte[] byteCode; + + private final int maxPoolSize; + private final int[] offsets; + private final byte[] types; + private final String[] utf8s; + private final int endOfPool; + + public ClassFileMetaData(byte[] byteCode) { + this.byteCode = byteCode; + + maxPoolSize = readValue(START_OF_CONSTANT_POOL); + offsets = new int[maxPoolSize]; + types = new byte[maxPoolSize]; + utf8s = new String[maxPoolSize]; + int position = 10; + for (int i = 1; i < maxPoolSize; i++) { + byte type = byteCode[position]; + types[i] = type; + position++; + offsets[i] = position; + switch (type) { + case UTF8: + int length = readValue(position); + position += 2; + utf8s[i] = decodeString(position, length); + position += length; + break; + case CLASS: + case STRING: + case METHOD_TYPE: + position += 2; + break; + case METHOD_HANDLE: + position += 3; + break; + case INTEGER: + case FLOAT: + case FIELD: + case METHOD: + case INTERFACE_METHOD: + case NAME_TYPE: + case INVOKE_DYNAMIC: + position += 4; + break; + case LONG: + case DOUBLE: + position += 8; + i++; + break; + case 0: + break; + default: + throw new AssertionError("Unknown constant pool type " + type); + } + } + endOfPool = position; + } + + private String decodeString(int pos, int size) { + int end = pos + size; + + // the resulting string might be smaller + StringBuilder result = new StringBuilder(size); + while (pos < end) { + int first = (byteCode[pos++] & 0xFF); + if (first < 0x80) { + result.append((char)first); + } else if ((first & 0xE0) == 0xC0) { + int x = (first & 0x1F) << 6; + int y = (byteCode[pos++] & 0x3F); + result.append((char)(x | y)); + } else { + int x = (first & 0x0F) << 12; + int y = (byteCode[pos++] & 0x3F) << 6; + int z = (byteCode[pos++] & 0x3F); + result.append((char)(x | y | z)); + } + } + return result.toString(); + } + + /** + * Checks if the constant pool contains the provided 'raw' string. These are used as source material for further JVM types, such as string constants, type references, etcetera. + */ + public boolean containsUtf8(String value) { + return findUtf8(value) != NOT_FOUND; + } + + /** + * Checks if the constant pool contains a reference to the provided class. + * + * NB: Most uses of a type do <em>NOT</em> show up as a class in the constant pool. + * For example, the parameter types and return type of any method you invoke or declare, are stored as signatures and not as type references, + * but the type to which any method you invoke belongs, is. Read the JVM Specification for more information. + * + * @param className must be provided JVM-style, such as {@code java/lang/String} + */ + public boolean usesClass(String className) { + return findClass(className) != NOT_FOUND; + } + + /** + * Checks if the constant pool contains a reference to a given field, either for writing or reading. + * + * @param className must be provided JVM-style, such as {@code java/lang/String} + */ + public boolean usesField(String className, String fieldName) { + int classIndex = findClass(className); + if (classIndex == NOT_FOUND) return false; + int fieldNameIndex = findUtf8(fieldName); + if (fieldNameIndex == NOT_FOUND) return false; + + for (int i = 1; i < maxPoolSize; i++) { + if (types[i] == FIELD && readValue(offsets[i]) == classIndex) { + int nameAndTypeIndex = readValue(offsets[i] + 2); + if (readValue(offsets[nameAndTypeIndex]) == fieldNameIndex) return true; + } + } + return false; + } + + /** + * Checks if the constant pool contains a reference to a given method, with any signature (return type and parameter types). + * + * @param className must be provided JVM-style, such as {@code java/lang/String} + */ + public boolean usesMethod(String className, String methodName) { + int classIndex = findClass(className); + if (classIndex == NOT_FOUND) return false; + int methodNameIndex = findUtf8(methodName); + if (methodNameIndex == NOT_FOUND) return false; + + for (int i = 1; i < maxPoolSize; i++) { + if (isMethod(i) && readValue(offsets[i]) == classIndex) { + int nameAndTypeIndex = readValue(offsets[i] + 2); + if (readValue(offsets[nameAndTypeIndex]) == methodNameIndex) return true; + } + } + return false; + } + + /** + * Checks if the constant pool contains a reference to a given method. + * + * @param className must be provided JVM-style, such as {@code java/lang/String} + * @param descriptor must be provided JVM-style, such as {@code (IZ)Ljava/lang/String;} + */ + public boolean usesMethod(String className, String methodName, String descriptor) { + int classIndex = findClass(className); + if (classIndex == NOT_FOUND) return false; + int nameAndTypeIndex = findNameAndType(methodName, descriptor); + if (nameAndTypeIndex == NOT_FOUND) return false; + + for (int i = 1; i < maxPoolSize; i++) { + if (isMethod(i) && + readValue(offsets[i]) == classIndex && + readValue(offsets[i] + 2) == nameAndTypeIndex) return true; + } + return false; + } + + /** + * Checks if the constant pool contains the provided string constant, which implies the constant is used somewhere in the code. + * + * NB: String literals get concatenated by the compiler. + */ + public boolean containsStringConstant(String value) { + int index = findUtf8(value); + if (index == NOT_FOUND) return false; + for (int i = 1; i < maxPoolSize; i++) { + if (types[i] == STRING && readValue(offsets[i]) == index) return true; + } + return false; + } + + /** + * Checks if the constant pool contains the provided long constant, which implies the constant is used somewhere in the code. + * + * NB: compile-time constant expressions are evaluated at compile time. + */ + public boolean containsLong(long value) { + for (int i = 1; i < maxPoolSize; i++) { + if (types[i] == LONG && readLong(i) == value) return true; + } + return false; + } + + /** + * Checks if the constant pool contains the provided double constant, which implies the constant is used somewhere in the code. + * + * NB: compile-time constant expressions are evaluated at compile time. + */ + public boolean containsDouble(double value) { + boolean isNan = Double.isNaN(value); + for (int i = 1; i < maxPoolSize; i++) { + if (types[i] == DOUBLE) { + double d = readDouble(i); + if (d == value || (isNan && Double.isNaN(d))) return true; + } + } + return false; + } + + /** + * Checks if the constant pool contains the provided int constant, which implies the constant is used somewhere in the code. + * + * NB: compile-time constant expressions are evaluated at compile time. + */ + public boolean containsInteger(int value) { + for (int i = 1; i < maxPoolSize; i++) { + if (types[i] == INTEGER && readInteger(i) == value) return true; + } + return false; + } + + /** + * Checks if the constant pool contains the provided float constant, which implies the constant is used somewhere in the code. + * + * NB: compile-time constant expressions are evaluated at compile time. + */ + public boolean containsFloat(float value) { + boolean isNan = Float.isNaN(value); + for (int i = 1; i < maxPoolSize; i++) { + if (types[i] == FLOAT) { + float f = readFloat(i); + if (f == value || (isNan && Float.isNaN(f))) return true; + } + } + return false; + } + + private long readLong(int index) { + int pos = offsets[index]; + return ((long)read32(pos)) << 32 | read32(pos + 4); + } + + private double readDouble(int index) { + int pos = offsets[index]; + long bits = ((long)read32(pos)) << 32 | (read32(pos + 4) & 0x00000000FFFFFFFF); + return Double.longBitsToDouble(bits); + } + + private long readInteger(int index) { + return read32(offsets[index]); + } + + private float readFloat(int index) { + return Float.intBitsToFloat(read32(offsets[index])); + } + + private int read32(int pos) { + return (byteCode[pos] & 0xFF) << 24 | (byteCode[pos + 1] & 0xFF) << 16 | (byteCode[pos + 2] & 0xFF) << 8 | (byteCode[pos + 3] &0xFF); + } + + /** + * Returns the name of the class in JVM format, such as {@code java/lang/String} + */ + public String getClassName() { + return getClassName(readValue(endOfPool + 2)); + } + + /** + * Returns the name of the superclass in JVM format, such as {@code java/lang/Object} + * + * NB: If you try this on Object itself, you'll get {@code null}.<br /> + * NB2: For interfaces and annotation interfaces, you'll always get {@code java/lang/Object} + */ + public String getSuperClassName() { + return getClassName(readValue(endOfPool + 4)); + } + + /** + * Returns the name of all implemented interfaces. + */ + public List<String> getInterfaces() { + int size = readValue(endOfPool + 6); + if (size == 0) return Collections.emptyList(); + + List<String> result = new ArrayList<String>(); + for (int i = 0; i < size; i++) { + result.add(getClassName(readValue(endOfPool + 8 + (i * 2)))); + } + return result; + } + + /** + * A {@code toString()} like utility to dump all contents of the constant pool into a string. + * + * NB: No guarantees are made about the exact layout of this string. It is for informational purposes only, don't try to parse it.<br /> + * NB2: After a double or long, there's a JVM spec-mandated gap, which is listed as {@code (cont.)} in the returned string. + */ + public String poolContent() { + StringBuilder result = new StringBuilder(); + for (int i = 1; i < maxPoolSize; i++) { + result.append(String.format("#%02x: ", i)); + int pos = offsets[i]; + switch(types[i]) { + case UTF8: + result.append("Utf8 ").append(utf8s[i]); + break; + case CLASS: + result.append("Class ").append(getClassName(i)); + break; + case STRING: + result.append("String \"").append(utf8s[readValue(pos)]).append("\""); + break; + case INTEGER: + result.append("int ").append(readInteger(i)); + break; + case FLOAT: + result.append("float ").append(readFloat(i)); + break; + case FIELD: + appendAccess(result.append("Field "), i); + break; + case METHOD: + case INTERFACE_METHOD: + appendAccess(result.append("Method "), i); + break; + case NAME_TYPE: + appendNameAndType(result.append("Name&Type "), i); + break; + case LONG: + result.append("long ").append(readLong(i)); + break; + case DOUBLE: + result.append("double ").append(readDouble(i)); + break; + case METHOD_HANDLE: + result.append("MethodHandle..."); + break; + case METHOD_TYPE: + result.append("MethodType..."); + break; + case INVOKE_DYNAMIC: + result.append("InvokeDynamic..."); + break; + case 0: + result.append("(cont.)"); + break; + } + result.append("\n"); + } + return result.toString(); + } + + private void appendAccess(StringBuilder result, int index) { + int pos = offsets[index]; + result.append(getClassName(readValue(pos))).append("."); + appendNameAndType(result, readValue(pos + 2)); + } + + private void appendNameAndType(StringBuilder result, int index) { + int pos = offsets[index]; + result.append(utf8s[readValue(pos)]).append(":").append(utf8s[readValue(pos + 2)]); + } + + private String getClassName(int classIndex) { + if (classIndex < 1) return null; + return utf8s[readValue(offsets[classIndex])]; + } + + private boolean isMethod(int i) { + byte type = types[i]; + return type == METHOD || type == INTERFACE_METHOD; + } + + private int findNameAndType(String name, String descriptor) { + int nameIndex = findUtf8(name); + if (nameIndex == NOT_FOUND) return NOT_FOUND; + int descriptorIndex = findUtf8(descriptor); + if (descriptorIndex == NOT_FOUND) return NOT_FOUND; + for (int i = 1; i < maxPoolSize; i++) { + if (types[i] == NAME_TYPE && + readValue(offsets[i]) == nameIndex && + readValue(offsets[i] + 2) == descriptorIndex) return i; + } + return NOT_FOUND; + } + + private int findUtf8(String value) { + for (int i = 1; i < maxPoolSize; i++) { + if (value.equals(utf8s[i])) { + return i; + } + } + return NOT_FOUND; + } + + private int findClass(String className) { + int index = findUtf8(className); + if (index == -1) return NOT_FOUND; + for (int i = 1; i < maxPoolSize; i++) { + if (types[i] == CLASS && readValue(offsets[i]) == index) return i; + } + return NOT_FOUND; + } + + private int readValue(int position) { + return ((byteCode[position] & 0xFF) << 8) | (byteCode[position + 1] & 0xFF); + } +} |