Created utility class to casually inspect class files on the usage of classes, fields and methods

3 files changed, 249 insertions, 3 deletions

diff --git a/src/core/lombok/bytecode/ClassFileMetaData.java b/src/core/lombok/bytecode/ClassFileMetaData.java
new file mode 100644
index 00000000..df50969a
--- /dev/null
+++ b/src/core/lombok/bytecode/ClassFileMetaData.java
@@ -0,0 +1,244 @@
+/*
+ * 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;
+
+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 IMETHOD = 11;
+	private static final byte NAME_TYPE = 12;
+	
+	private static final int NOT_FOUND = -1;
+	
+	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(8) + 1;
+		offsets = new int[maxPoolSize];
+		types = new byte[maxPoolSize];
+		utf8s = new String[maxPoolSize];
+		int position = 10;
+		for (int i = 1; i < maxPoolSize - 1; 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:
+				position += 2;
+				break;
+			case INTEGER:
+			case FLOAT:
+			case FIELD:
+			case METHOD:
+			case IMETHOD:
+			case NAME_TYPE:
+				position += 4;
+				break;
+			case LONG:
+			case DOUBLE:
+				position += 8;
+				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();
+	}
+	
+	public boolean containsUtf8(String value) {
+		return findUtf8(value) != NOT_FOUND;
+	}
+	
+	public boolean usesClass(String className) {
+		return findClass(className) != NOT_FOUND;
+	}
+	
+	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;
+	}
+	
+	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;
+	}
+	
+	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;
+	}
+	
+	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;
+	}
+	
+	public String getClassName() {
+		return getClassName(readValue(endOfPool + 2));
+	}
+	
+	public String getSuperClassName() {
+		return getClassName(readValue(endOfPool + 4));
+	}
+	
+	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;
+	}
+	
+	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 == IMETHOD;
+	}
+	
+	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);
+	}
+}
\ No newline at end of file
diff --git a/src/core/lombok/bytecode/PostCompilerApp.java b/src/core/lombok/bytecode/PostCompilerApp.java
index 3a413d67..e1b177ba 100644
--- a/src/core/lombok/bytecode/PostCompilerApp.java
+++ b/src/core/lombok/bytecode/PostCompilerApp.java
@@ -130,8 +130,8 @@ public class PostCompilerApp implements LombokApp {
 			else if (f.getName().endsWith(".class")) filesToProcess.add(f);
 		}
 	}
-
-	private static byte[] readFile(File file) throws IOException {
+	
+	static byte[] readFile(File file) throws IOException {
 		byte[] buffer = new byte[1024];
 		ByteArrayOutputStream bytes = new ByteArrayOutputStream();
 		FileInputStream fileInputStream = new FileInputStream(file);
@@ -144,7 +144,7 @@ public class PostCompilerApp implements LombokApp {
 		return bytes.toByteArray();
 	}
 	
-	private static void writeFile(File file, byte[] transformed) throws IOException {
+	static void writeFile(File file, byte[] transformed) throws IOException {
 		FileOutputStream out = new FileOutputStream(file);
 		out.write(transformed);
 		out.close();
diff --git a/src/core/lombok/bytecode/SneakyThrowsRemover.java b/src/core/lombok/bytecode/SneakyThrowsRemover.java
index 4d69ab34..fde29924 100644
--- a/src/core/lombok/bytecode/SneakyThrowsRemover.java
+++ b/src/core/lombok/bytecode/SneakyThrowsRemover.java
@@ -72,6 +72,8 @@ public class SneakyThrowsRemover implements PostCompilerTransformation {
 	}
 	
 	@Override public byte[] applyTransformations(byte[] original, String className, DiagnosticsReceiver diagnostics) {
+		if (!new ClassFileMetaData(original).usesMethod("lombok/Lombok", "sneakyThrow")) return null;
+		
 		byte[] fixedByteCode = fixJSRInlining(original);
 		
 		ClassReader reader = new ClassReader(fixedByteCode);