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Introduction to Class File Format & Byte Code

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Doug Hawkins

The document discusses the class file format and byte code in Java. It provides an overview of the class file structure, including the constant pool, fields, methods, and attributes sections. It also explains how the Java virtual machine is stack-based and executes byte code instructions that involve operating on the operand stack, such as arithmetic, logic, object creation and method invocation operations. Finally, it demonstrates how parameters and local variables are handled in byte code through an example method.

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Introduction to Class File Format & Byte Code By Douglas Q Hawkins Wireless Event Code: JM67
Topics Class File Format Byte Code Dynamic Generation of Byte Code Annotation Processing Tool
Class File Format
Class File Format CA FE BA BE Minor Version Major Version Constant Pool Flags This Class Super Class Interfaces Fields Methods Attributes
Class File Format CA FE BA BE Minor Version Major Version Constant Pool Flags This Class Super Class Interfaces Fields Methods Attributes
Class File Format CA FE BA BE Minor Version Major Version Constant Pool Flags This Class Super Class Interfaces Fields Methods Attributes
Class File Format CA FE BA BE Minor Version Major Version Constant Pool Flags This Class Super Class Interfaces Fields Methods Attributes
Class File Format CA FE BA BE Minor Version Major Version Constant Pool d ize gs on ar hr ar nc su atile t/v pu te d Flags This Class Super Class al sy ce iva te tiv ct l n ab tfp vo nsie pr ec fin r/ na ra fa ic tra e pr ic pe Interfaces st er bl ric ot at int st st Fields Methods Attributes
Class File Format CA FE BA BE Minor Version Major Version Constant Pool Flags This Class Super Class Interfaces Fields Methods Attributes
Class File Format CA FE BA BE Minor Version Major Version Constant Pool Flags This Class Super Class Interfaces Fields Methods Attributes
Class File Format CA FE BA BE Minor Version Major Version Constant Pool Flags This Class Super Class Interfaces Fields Methods Attributes
Class File Format CA FE BA BE Minor Version Major Version Constant Pool Flags This Class Super Class Interfaces Fields Methods Attributes
Class File Format CA FE BA BE Minor Version Major Version Constant Pool Flags This Class Super Class Interfaces Fields Methods Attributes
Class File Format CA FE BA BE Minor Version Major Version Constant Pool Flags This Class Super Class Interfaces Fields Methods Attributes
Constant Pool C 2 UTF 10 HelloWorld C 4 UTF 16 “java/lang/Object” UTF 6 “<init>” UTF 3 “()V” UTF 4 “Code” M 3 9 N&T 5 6 UTF 4 “main” UTF 22 “([Ljava/lang/String;)V” F 13 15 C 14 UTF 16 “java/lang/System”
Constant Pool (continued) N&T 16 17 UTF 3 “out” UTF 21 “Ljava/io/PrintStream;” S 19 UTF 11 “Hello World” M21 23 C 22 UTF 19 “java/io/PrintStream” N&T 24 25 UTF 7 “println” UTF 21 (Ljava/lang/String;)V
Field Format Flags Name Descriptor Attributes
Name Flags Field Format int er fa ce st ric Attributes ab tfp s na tra tiv ct tra e vo nsie Descriptor l n su atile t/v pe ar fin r/ ar al sy gs st nc at hr pr ic on ot ize pr ec iva te d pu te d bl ic
Field Format Flags Name Descriptor “name” Attributes
Field Format Flags Name Descriptor “Ljava/lang/String;” Attributes
Field Format Flags Name Descriptor Attributes
Field Format Flags Name Descriptor Attributes ConstantValue
Method Format Flags Name Descriptor Attributes
Name Flags int er fa ce Method Format st ric Attributes ab tfp s na tra tiv ct tra e vo nsie Descriptor l n su atile t/v pe ar fin r/ ar al sy gs st nc at hr pr ic on ot ize pr ec iva te d pu te d bl ic
Method Format Flags Name Descriptor “main” Attributes
Method Format Flags Name Descriptor “([Ljava/lang/String;)V” Attributes
Method Format Flags Name Descriptor Attributes
Method Format Flags Name Descriptor Attributes Exceptions
Method Format Flags Name Descriptor Attributes Exceptions Code
Constant Pool C 2 UTF 10 HelloWorld C 4 UTF 16 “java/lang/Object” UTF 6 “<init>” UTF 3 “()V” UTF 4 “Code” M 3 9 N&T 5 6 UTF 4 “main” UTF 22 “([Ljava/lang/String;)V” F 13 15 C 14 UTF 16 “java/lang/System”
Constant Pool 1 2 C 2 UTF 10 HelloWorld 3 4 C 4 UTF 16 “java/lang/Object” 5 6 UTF 6 “<init>” UTF 7 3 “()V” UTF 4 “Code” 8 9 10 M 3 9 N&T 5 6 UTF 4 11 “main” UTF 22 “([Ljava/lang/String;)V” 12 13 14 F 13 15 C 14 UTF 16 “java/lang/System”
Constant Pool 1 2 C 2 UTF 10 HelloWorld 3 4 C 4 UTF 16 “java/lang/Object” 5 6 UTF 6 “<init>” UTF 7 3 “()V” UTF 4 “Code” 8 9 10 M 3 9 N&T 5 6 UTF 4 11 “main” UTF 22 “([Ljava/lang/String;)V” 12 13 14 F 13 15 C 14 UTF 16 “java/lang/System”
Constant Pool 1 2 C 2 UTF 10 HelloWorld 3 4 C 4 UTF 16 “java/lang/Object” 5 6 UTF 6 “<init>” UTF 7 3 “()V” UTF 4 “Code” 8 9 10 M 3 9 N&T 5 6 UTF 4 11 “main” UTF 22 “([Ljava/lang/String;)V” 12 13 14 F 13 15 C 14 UTF 16 “java/lang/System”
Browsing Class File Format JClassLib Viewer
Byte Code
Stack Based Virtual Machine 0 iconst_1 0 1 2 3 1 iconst_2 2 iadd 3 istore_0 4 iload_0
Stack Based Virtual Machine 0 iconst_1 0 1 2 3 1 iconst_2 2 iadd 3 istore_0 4 iload_0 1
Stack Based Virtual Machine 0 iconst_1 0 1 2 3 1 iconst_2 2 iadd 3 istore_0 4 iload_0 2 1
Stack Based Virtual Machine 0 iconst_1 0 1 2 3 1 iconst_2 2 iadd 3 istore_0 4 iload_0 1+2
Stack Based Virtual Machine 0 iconst_1 0 1 2 3 1 iconst_2 2 iadd 3 istore_0 4 iload_0 3
Stack Based Virtual Machine 0 iconst_1 0 1 2 3 1 iconst_2 3 2 iadd 3 istore_0 4 iload_0
Stack Based Virtual Machine 0 iconst_1 0 1 2 3 1 iconst_2 3 2 iadd 3 istore_0 4 iload_0 3
Operation Types Load and Store Arithmetic and Logic Type Conversion Branch Instructions Object Creation and Manipulation Operand Stack Method Invocation
Data Types ac ts refix als ns e P ray oc Co Cod By ture Ar k / L St tan na te Sig boolean Z Integer Types byte B b char C c short S s int I i long J l float F f double D d reference L a void V
Parameters and Local Variables static int volume( int width, int depth, int height ) { int area = width * depth; int volume = area * height; return volume; }
Parameters and Local Variables static int volume( 0 iload_0 int width, 1 iload_1 int depth, int height ) 2 imul { 3 istore_3 int area = width * depth; 4 iload_3 int volume = area * height; return volume; 5 iload_2 } 6 imul 7 istore 4 9 iload 4 11ireturn
Parameters and Local Variables static int volume( 0 iload_0 int width, 1 iload_1 int depth, 2 imul e int height ) are t h lum igh h pt a dt { 3 istore_3 de he vo wi 0 1 2 3 4 int area = width * depth; 4 iload_3 int volume = area * height; return volume; 5 iload_2 } 6 imul 7 istore 4 9 iload 4 11ireturn
Parameters and Local Variables static int volume( 0 iload_0 int width, 1 iload_1 int depth, 2 imul e int height ) are t h lum igh h pt a dt { 3 istore_3 de he vo wi 0 1 2 3 4 int area = width * depth; 4 iload_3 1 2 3 int volume = area * height; return volume; 5 iload_2 } 6 imul 7 istore 4 9 iload 4 11ireturn
Parameters and Local Variables static int volume( 0 iload_0 int width, 1 iload_1 int depth, 2 imul e int height ) are t h lum igh h pt a dt { 3 istore_3 de he vo wi 0 1 2 3 4 int area = width * depth; 4 iload_3 1 2 3 int volume = area * height; return volume; 5 iload_2 } 6 imul 7 istore 4 9 iload 4 11ireturn 1
Parameters and Local Variables static int volume( 0 iload_0 int width, 1 iload_1 int depth, 2 imul e int height ) are t h lum igh h pt a dt { 3 istore_3 de he vo wi 0 1 2 3 4 int area = width * depth; 4 iload_3 1 2 3 int volume = area * height; return volume; 5 iload_2 } 6 imul 7 istore 4 9 iload 4 2 11ireturn 1
Parameters and Local Variables static int volume( 0 iload_0 int width, 1 iload_1 int depth, 2 imul e int height ) are t h lum igh h pt a dt { 3 istore_3 de he vo wi 0 1 2 3 4 int area = width * depth; 4 iload_3 1 2 3 int volume = area * height; return volume; 5 iload_2 } 6 imul 7 istore 4 9 iload 4 11ireturn 2
Parameters and Local Variables static int volume( 0 iload_0 int width, 1 iload_1 int depth, 2 imul e int height ) are t h lum igh h pt a dt { 3 istore_3 de he vo wi 0 1 2 3 4 int area = width * depth; 4 iload_3 1 2 3 2 int volume = area * height; return volume; 5 iload_2 } 6 imul 7 istore 4 9 iload 4 11ireturn
Parameters and Local Variables static int volume( 0 iload_0 int width, 1 iload_1 int depth, 2 imul e int height ) are t h lum igh h pt a dt { 3 istore_3 de he vo wi 0 1 2 3 4 int area = width * depth; 4 iload_3 1 2 3 2 int volume = area * height; return volume; 5 iload_2 } 6 imul 7 istore 4 9 iload 4 11ireturn 2
Parameters and Local Variables static int volume( 0 iload_0 int width, 1 iload_1 int depth, 2 imul e int height ) are t h lum igh h pt a dt { 3 istore_3 de he vo wi 0 1 2 3 4 int area = width * depth; 4 iload_3 1 2 3 2 int volume = area * height; return volume; 5 iload_2 } 6 imul 7 istore 4 9 iload 4 3 11ireturn 2
Parameters and Local Variables static int volume( 0 iload_0 int width, 1 iload_1 int depth, 2 imul e int height ) are t h lum igh h pt a dt { 3 istore_3 de he vo wi 0 1 2 3 4 int area = width * depth; 4 iload_3 1 2 3 2 int volume = area * height; return volume; 5 iload_2 } 6 imul 7 istore 4 9 iload 4 11ireturn 6
Parameters and Local Variables static int volume( 0 iload_0 int width, 1 iload_1 int depth, 2 imul e int height ) are t h lum igh h pt a dt { 3 istore_3 de he vo wi 0 1 2 3 4 int area = width * depth; 4 iload_3 1 2 3 2 6 int volume = area * height; return volume; 5 iload_2 } 6 imul 7 istore 4 9 iload 4 11ireturn
Parameters and Local Variables static int volume( 0 iload_0 int width, 1 iload_1 int depth, 2 imul e int height ) are t h lum igh h pt a dt { 3 istore_3 de he vo wi 0 1 2 3 4 int area = width * depth; 4 iload_3 1 2 3 2 6 int volume = area * height; return volume; 5 iload_2 } 6 imul 7 istore 4 9 iload 4 11ireturn 6
Parameters and Local Variables static int volume( 0 iload_0 int width, 1 iload_1 int depth, 2 imul e int height ) are t h lum igh h pt a dt { 3 istore_3 de he vo wi 0 1 2 3 4 int area = width * depth; 4 iload_3 1 2 3 2 6 int volume = area * height; return volume; 5 iload_2 } 6 imul 7 istore 4 9 iload 4 11ireturn
Static vs Virtual Methods static int volume( 0 iload_0 int width, 1 iload_1 int depth, 2 imul e int height ) are t he h lum h igh pt a dt { 3 istore_3 de wi vo 0 1 2 3 4 5 int area = width * depth; 4 iload_3 int volume = area * height; return volume; 5 iload_2 } 6 imul 7 istore 4 9 iload 4 11 ireturn
Static vs Virtual Methods int volume( 0 iload_0 int width, 1 iload_1 int depth, 2 imul e int height ) are t he h lum h igh pt a dt { 3 istore_3 de wi vo 0 1 2 3 4 5 int area = width * depth; 4 iload_3 int volume = area * height; return volume; 5 iload_2 } 6 imul 7 istore 4 9 iload 4 11 ireturn
Static vs Virtual Methods int volume( 0 iload_0 int width, 1 iload_1 int depth, 2 imul e int height ) are t he h lum h igh pt a dt s { 3 istore_3 de thi wi vo 0 1 2 3 4 5 int area = width * depth; 4 iload_3 int volume = area * height; return volume; 5 iload_2 } 6 imul 7 istore 4 9 iload 4 11 ireturn
Static vs Virtual Methods int volume( 0 iload_1 int width, 1 iload_2 int depth, 2 imul e int height ) are t he h lum h igh pt a dt s { 3 istore 4 de thi wi vo 0 1 2 3 4 5 int area = width * depth; 5 iload 4 int volume = area * height; return volume; 7 iload_3 } 8 imul 9 istore 5 11 iload 5 13 ireturn
Hello World System.out.println( “Hello World” );
Hello World System.out.println( “Hello World” ); 0 getstatic System.out 3 ldc “Hello World” 5 invokevirtual PrintStream.println 8 return
Hello World System.out.println( “Hello World” ); 0 1 2 3 0 getstatic System.out 3 ldc “Hello World” 5 invokevirtual PrintStream.println “Hello World” 8 return System.out
Hello World System.out.println( “Hello World” ); 0 1 2 3 0 getstatic System.out 3 ldc “Hello World” 5 invokevirtual PrintStream.println “Hello World” 8 return System.out
Hello World System.out.println( “Hello World” ); 0 1 2 3 0 getstatic System.out 3 ldc “Hello World” 5 invokevirtual PrintStream.println “Hello World” 8 return System.out
Hello World g s ms thi System.out.println( “Hello World” ); 0 1 2 3 0 getstatic System.out 3 ldc “Hello World” 5 invokevirtual PrintStream.println “Hello World” 8 return System.out
Types of Method Invocations invokestatic - invoke static methods invokevirtual - invoke instance method from class invokeinterface - invoke instance method from interface invokespecial - invoke <init> / invoke super method
New Object return new BigDecimal(“2.0”);
New Object return new BigDecimal(“2.0”); 0 new BigDecimal 3 dup 4 ldc “2.0” 6 invokespecial BigDecimal.<init> 9 areturn
New Object return new BigDecimal(“2.0”); 0 1 2 3 0 new BigDecimal 3 dup 4 ldc “2.0” “2.0” 6 invokespecial BigDecimal.<init> 9 areturn
New Object return new BigDecimal(“2.0”); 0 1 2 3 0 new BigDecimal 3 dup 4 ldc “2.0” “2.0” 6 invokespecial BigDecimal.<init> 9 areturn BigDecimal
New Object return new BigDecimal(“2.0”); 0 1 2 3 0 new BigDecimal 3 dup 4 ldc “2.0” “2.0” 6 invokespecial BigDecimal.<init> 9 areturn BigDecimal
New Object return new BigDecimal(“2.0”); 0 1 2 3 0 new BigDecimal 3 dup 4 ldc “2.0” “2.0” 6 invokespecial BigDecimal.<init> 9 areturn BigDecimal
New Object return new BigDecimal(“2.0”); 0 1 2 3 0 new BigDecimal 3 dup 4 ldc “2.0” “2.0” 6 invokespecial BigDecimal.<init> 9 areturn BigDecimal
If / Else static boolean isPositive( int val ){ if ( val > 0 ) { return true; } else { return false; } }
If / Else static boolean isPositive( int val ){ 0 iload_0 test if ( val > 0 ) { 1 ifle +5 //6 return true; 4 iconst_1 } else { if return false; 5 ireturn } 6 iconst_0 else } 7 ireturn
If / Else static boolean isPositive( int val ){ 0 iload_0 test if ( val > 0 ) { 1 ifle +5 //6 return true; 4 iconst_1 } else { if return false; 5 ireturn } 6 iconst_0 else } 7 ireturn
If / Else static boolean isPositive( int val ){ 0 iload_0 test if ( val > 0 ) { 1 ifle +5 //6 return true; 4 iconst_1 } else { if return false; 5 ireturn } 6 iconst_0 else } 7 ireturn
If / Else static boolean isPositive( int val ){ 0 iload_0 test if ( val > 0 ) { 1 ifle +5 //6 return true; 4 iconst_1 } else { if return false; 5 ireturn } 6 iconst_0 else } 7 ireturn
If / Else static boolean isPositive( int val ){ 0 iload_0 test if ( val > 0 ) { 1 ifle +5 //6 return true; 4 iconst_1 } else { if return false; 5 ireturn } 6 iconst_0 else } 7 ireturn static boolean isPositive( int val ){ return ( val > 0 ); }
If / Else static boolean isPositive( int val ){ if ( val > 0 ) { return true; } else { return false; } } static boolean isPositive( int val ){ return ( val > 0 ); }
If / Else static boolean isPositive( int val ){ 0 iload_0 test if ( val > 0 ) { 1 ifle +5 //6 return true; 4 iconst_1 } else { if return false; 5 ireturn } 6 iconst_0 else } 7 ireturn static boolean isPositive( int val ){ return ( val > 0 ); }
For Loop static int sum( int min, int max ){ int sum = 0; for ( int i=min; i<max; ++i ){ sum += i; } return sum; }
before 0 iconst_0 For Loop init & test loop 1 istore_2 2 iload_1 static int sum( int min, int max ){ 3 istore_3 int sum = 0; 4 goto +10 //14 for ( int i=min; i<max; ++i ){ 7 iload_2 loop body sum += i; 8 iload_3 } 9 iadd return sum; 10 istore_2 } inc 11 iinc 3 by 1 14 iload_3 test 15 iload_1 16 if_icmplt -9 //7 19 iload_2 after loop 20 ireturn
before 0 iconst_0 For Loop init & test loop 1 istore_2 2 iload_1 static int sum( int min, int max ){ 3 istore_3 int sum = 0; 4 goto +10 //14 for ( int i=min; i<max; ++i ){ 7 iload_2 loop body sum += i; 8 iload_3 } 9 iadd return sum; 10 istore_2 } inc 11 iinc 3 by 1 14 iload_3 test 15 iload_1 16 if_icmplt -9 //7 19 iload_2 after loop 20 ireturn
before 0 iconst_0 For Loop init & test loop 1 istore_2 2 iload_1 static int sum( int min, int max ){ 3 istore_3 int sum = 0; 4 goto +10 //14 for ( int i=min; i<max; ++i ){ 7 iload_2 loop body sum += i; 8 iload_3 } 9 iadd return sum; 10 istore_2 } inc 11 iinc 3 by 1 14 iload_3 test 15 iload_1 16 if_icmplt -9 //7 19 iload_2 after loop 20 ireturn
before 0 iconst_0 For Loop init & test loop 1 istore_2 2 iload_1 static int sum( int min, int max ){ 3 istore_3 int sum = 0; 4 goto +10 //14 for ( int i=min; i<max; ++i ){ 7 iload_2 loop body sum += i; 8 iload_3 } 9 iadd return sum; 10 istore_2 } inc 11 iinc 3 by 1 14 iload_3 test 15 iload_1 16 if_icmplt -9 //7 19 iload_2 after loop 20 ireturn
before 0 iconst_0 For Loop init & test loop 1 istore_2 2 iload_1 static int sum( int min, int max ){ 3 istore_3 int sum = 0; 4 goto +10 //14 for ( int i=min; i<max; ++i ){ 7 iload_2 loop body sum += i; 8 iload_3 } 9 iadd return sum; 10 istore_2 } inc 11 iinc 3 by 1 14 iload_3 test 15 iload_1 16 if_icmplt -9 //7 19 iload_2 after loop 20 ireturn
before 0 iconst_0 For Loop init & test loop 1 istore_2 2 iload_1 static int sum( int min, int max ){ 3 istore_3 int sum = 0; 4 goto +10 //14 for ( int i=min; i<max; ++i ){ 7 iload_2 loop body sum += i; 8 iload_3 } 9 iadd return sum; 10 istore_2 } inc 11 iinc 3 by 1 14 iload_3 test 15 iload_1 16 if_icmplt -9 //7 19 iload_2 after loop 20 ireturn
before 0 iconst_0 For Loop init & test loop 1 istore_2 2 iload_1 static int sum( int min, int max ){ 3 istore_3 int sum = 0; 4 goto +10 //14 for ( int i=min; i<max; ++i ){ 7 iload_2 loop body sum += i; 8 iload_3 } 9 iadd return sum; 10 istore_2 } inc 11 iinc 3 by 1 14 iload_3 test 15 iload_1 16 if_icmplt -9 //7 19 iload_2 after loop 20 ireturn
Exception Handling static int read( InputStream in ) { try { return in.read(); } catch ( IOException e ) { return -1; } finally { IoUtils.closeQuietly( in ); } }
0 aload_0 Exception Handling 1 invokevirtual InputStream.read try / finally static int read( InputStream in ) { 4 istore_1 try { 5 aload_0 return in.read(); 6 invokestatic IoUtils.closeQuietly } catch ( IOException e ) { 9 iload_1 return -1; 10 ireturn } finally { 11 pop IoUtils.closeQuietly( in ); catch / finally 12 aload_0 } 13 invokestatic IoUtils.closeQuietly } 16 iconst_m1 17 ireturn 18 astore_2 19 aload_0 finally 20 invokestatic IoUtils.closeQuietly 23 aload_2 24 athrow
0 aload_0 Exception Handling 1 invokevirtual InputStream.read try / finally static int read( InputStream in ) { 4 istore_1 try { 5 aload_0 return in.read(); 6 invokestatic IoUtils.closeQuietly } catch ( IOException e ) { 9 iload_1 return -1; 10 ireturn } finally { 11 pop IoUtils.closeQuietly( in ); catch / finally 12 aload_0 } 13 invokestatic IoUtils.closeQuietly } 16 iconst_m1 17 ireturn 18 astore_2 19 aload_0 finally 20 invokestatic IoUtils.closeQuietly 23 aload_2 24 athrow
0 aload_0 Exception Handling 1 invokevirtual InputStream.read try / finally static int read( InputStream in ) { 4 istore_1 try { 5 aload_0 return in.read(); 6 invokestatic IoUtils.closeQuietly } catch ( IOException e ) { 9 iload_1 return -1; 10 ireturn } finally { 11 pop IoUtils.closeQuietly( in ); catch / finally 12 aload_0 } 13 invokestatic IoUtils.closeQuietly } 16 iconst_m1 17 ireturn Exception Table 18 astore_2 start end handler Exception 19 aload_0 0 5 11 IOException finally 20 invokestatic IoUtils.closeQuietly 0 5 18 any 23 aload_2 11 12 18 any 24 athrow
0 aload_0 Exception Handling 1 invokevirtual InputStream.read try / finally static int read( InputStream in ) { 4 istore_1 try { 5 aload_0 return in.read(); 6 invokestatic IoUtils.closeQuietly } catch ( IOException e ) { 9 iload_1 return -1; 10 ireturn } finally { 11 pop IoUtils.closeQuietly( in ); catch / finally 12 aload_0 } 13 invokestatic IoUtils.closeQuietly } 16 iconst_m1 17 ireturn Exception Table 18 astore_2 start end handler Exception 19 aload_0 0 5 11 IOException finally 20 invokestatic IoUtils.closeQuietly 0 5 18 any 23 aload_2 11 12 18 any 24 athrow
More Attributes... Java 1.2+ InnerClass Synthetic Deprecated
More Attributes... Java 1.2+ InnerClass Synthetic Deprecated Debugging LineNumberTable LocalVariableTable SourceFile
More Attributes... Java 1.2+ Java 5+ InnerClass Signature Synthetic RuntimeVisibleAnnotations Deprecated RuntimeInvisibleAnnotations Debugging LineNumberTable LocalVariableTable SourceFile
Byte Code Generation
Resources The Java Virtual Machine Specification http://java.sun.com/docs/books/jvms/ JClassLib Viewer http://www.ej-technologies.com/products/jclasslib/ overview.html Maxine VM http://labs.oracle.com/projects/maxine/ New Features in Java 6 - Annotation Processing http://www.javabeat.net/articles/14-java-60-features- part-2-pluggable-annotation-proce-1.html

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Introduction to Class File Format & Byte Code

  • 1. Introduction to Class File Format & Byte Code By Douglas Q Hawkins Wireless Event Code: JM67
  • 2. Topics Class File Format Byte Code Dynamic Generation of Byte Code Annotation Processing Tool
  • 4. Class File Format CA FE BA BE Minor Version Major Version Constant Pool Flags This Class Super Class Interfaces Fields Methods Attributes
  • 5. Class File Format CA FE BA BE Minor Version Major Version Constant Pool Flags This Class Super Class Interfaces Fields Methods Attributes
  • 6. Class File Format CA FE BA BE Minor Version Major Version Constant Pool Flags This Class Super Class Interfaces Fields Methods Attributes
  • 7. Class File Format CA FE BA BE Minor Version Major Version Constant Pool Flags This Class Super Class Interfaces Fields Methods Attributes
  • 8. Class File Format CA FE BA BE Minor Version Major Version Constant Pool d ize gs on ar hr ar nc su atile t/v pu te d Flags This Class Super Class al sy ce iva te tiv ct l n ab tfp vo nsie pr ec fin r/ na ra fa ic tra e pr ic pe Interfaces st er bl ric ot at int st st Fields Methods Attributes
  • 9. Class File Format CA FE BA BE Minor Version Major Version Constant Pool Flags This Class Super Class Interfaces Fields Methods Attributes
  • 10. Class File Format CA FE BA BE Minor Version Major Version Constant Pool Flags This Class Super Class Interfaces Fields Methods Attributes
  • 11. Class File Format CA FE BA BE Minor Version Major Version Constant Pool Flags This Class Super Class Interfaces Fields Methods Attributes
  • 12. Class File Format CA FE BA BE Minor Version Major Version Constant Pool Flags This Class Super Class Interfaces Fields Methods Attributes
  • 13. Class File Format CA FE BA BE Minor Version Major Version Constant Pool Flags This Class Super Class Interfaces Fields Methods Attributes
  • 14. Class File Format CA FE BA BE Minor Version Major Version Constant Pool Flags This Class Super Class Interfaces Fields Methods Attributes
  • 15. Constant Pool C 2 UTF 10 HelloWorld C 4 UTF 16 “java/lang/Object” UTF 6 “<init>” UTF 3 “()V” UTF 4 “Code” M 3 9 N&T 5 6 UTF 4 “main” UTF 22 “([Ljava/lang/String;)V” F 13 15 C 14 UTF 16 “java/lang/System”
  • 16. Constant Pool (continued) N&T 16 17 UTF 3 “out” UTF 21 “Ljava/io/PrintStream;” S 19 UTF 11 “Hello World” M21 23 C 22 UTF 19 “java/io/PrintStream” N&T 24 25 UTF 7 “println” UTF 21 (Ljava/lang/String;)V
  • 17. Field Format Flags Name Descriptor Attributes
  • 18. Name Flags Field Format int er fa ce st ric Attributes ab tfp s na tra tiv ct tra e vo nsie Descriptor l n su atile t/v pe ar fin r/ ar al sy gs st nc at hr pr ic on ot ize pr ec iva te d pu te d bl ic
  • 19. Field Format Flags Name Descriptor “name” Attributes
  • 20. Field Format Flags Name Descriptor “Ljava/lang/String;” Attributes
  • 21. Field Format Flags Name Descriptor Attributes
  • 22. Field Format Flags Name Descriptor Attributes ConstantValue
  • 23. Method Format Flags Name Descriptor Attributes
  • 24. Name Flags int er fa ce Method Format st ric Attributes ab tfp s na tra tiv ct tra e vo nsie Descriptor l n su atile t/v pe ar fin r/ ar al sy gs st nc at hr pr ic on ot ize pr ec iva te d pu te d bl ic
  • 25. Method Format Flags Name Descriptor “main” Attributes
  • 26. Method Format Flags Name Descriptor “([Ljava/lang/String;)V” Attributes
  • 27. Method Format Flags Name Descriptor Attributes
  • 28. Method Format Flags Name Descriptor Attributes Exceptions
  • 29. Method Format Flags Name Descriptor Attributes Exceptions Code
  • 30. Constant Pool C 2 UTF 10 HelloWorld C 4 UTF 16 “java/lang/Object” UTF 6 “<init>” UTF 3 “()V” UTF 4 “Code” M 3 9 N&T 5 6 UTF 4 “main” UTF 22 “([Ljava/lang/String;)V” F 13 15 C 14 UTF 16 “java/lang/System”
  • 31. Constant Pool 1 2 C 2 UTF 10 HelloWorld 3 4 C 4 UTF 16 “java/lang/Object” 5 6 UTF 6 “<init>” UTF 7 3 “()V” UTF 4 “Code” 8 9 10 M 3 9 N&T 5 6 UTF 4 11 “main” UTF 22 “([Ljava/lang/String;)V” 12 13 14 F 13 15 C 14 UTF 16 “java/lang/System”
  • 32. Constant Pool 1 2 C 2 UTF 10 HelloWorld 3 4 C 4 UTF 16 “java/lang/Object” 5 6 UTF 6 “<init>” UTF 7 3 “()V” UTF 4 “Code” 8 9 10 M 3 9 N&T 5 6 UTF 4 11 “main” UTF 22 “([Ljava/lang/String;)V” 12 13 14 F 13 15 C 14 UTF 16 “java/lang/System”
  • 33. Constant Pool 1 2 C 2 UTF 10 HelloWorld 3 4 C 4 UTF 16 “java/lang/Object” 5 6 UTF 6 “<init>” UTF 7 3 “()V” UTF 4 “Code” 8 9 10 M 3 9 N&T 5 6 UTF 4 11 “main” UTF 22 “([Ljava/lang/String;)V” 12 13 14 F 13 15 C 14 UTF 16 “java/lang/System”
  • 34. Browsing Class File Format JClassLib Viewer
  • 36. Stack Based Virtual Machine 0 iconst_1 0 1 2 3 1 iconst_2 2 iadd 3 istore_0 4 iload_0
  • 37. Stack Based Virtual Machine 0 iconst_1 0 1 2 3 1 iconst_2 2 iadd 3 istore_0 4 iload_0 1
  • 38. Stack Based Virtual Machine 0 iconst_1 0 1 2 3 1 iconst_2 2 iadd 3 istore_0 4 iload_0 2 1
  • 39. Stack Based Virtual Machine 0 iconst_1 0 1 2 3 1 iconst_2 2 iadd 3 istore_0 4 iload_0 1+2
  • 40. Stack Based Virtual Machine 0 iconst_1 0 1 2 3 1 iconst_2 2 iadd 3 istore_0 4 iload_0 3
  • 41. Stack Based Virtual Machine 0 iconst_1 0 1 2 3 1 iconst_2 3 2 iadd 3 istore_0 4 iload_0
  • 42. Stack Based Virtual Machine 0 iconst_1 0 1 2 3 1 iconst_2 3 2 iadd 3 istore_0 4 iload_0 3
  • 43. Operation Types Load and Store Arithmetic and Logic Type Conversion Branch Instructions Object Creation and Manipulation Operand Stack Method Invocation
  • 44. Data Types ac ts refix als ns e P ray oc Co Cod By ture Ar k / L St tan na te Sig boolean Z Integer Types byte B b char C c short S s int I i long J l float F f double D d reference L a void V
  • 45. Parameters and Local Variables static int volume( int width, int depth, int height ) { int area = width * depth; int volume = area * height; return volume; }
  • 46. Parameters and Local Variables static int volume( 0 iload_0 int width, 1 iload_1 int depth, int height ) 2 imul { 3 istore_3 int area = width * depth; 4 iload_3 int volume = area * height; return volume; 5 iload_2 } 6 imul 7 istore 4 9 iload 4 11ireturn
  • 47. Parameters and Local Variables static int volume( 0 iload_0 int width, 1 iload_1 int depth, 2 imul e int height ) are t h lum igh h pt a dt { 3 istore_3 de he vo wi 0 1 2 3 4 int area = width * depth; 4 iload_3 int volume = area * height; return volume; 5 iload_2 } 6 imul 7 istore 4 9 iload 4 11ireturn
  • 48. Parameters and Local Variables static int volume( 0 iload_0 int width, 1 iload_1 int depth, 2 imul e int height ) are t h lum igh h pt a dt { 3 istore_3 de he vo wi 0 1 2 3 4 int area = width * depth; 4 iload_3 1 2 3 int volume = area * height; return volume; 5 iload_2 } 6 imul 7 istore 4 9 iload 4 11ireturn
  • 49. Parameters and Local Variables static int volume( 0 iload_0 int width, 1 iload_1 int depth, 2 imul e int height ) are t h lum igh h pt a dt { 3 istore_3 de he vo wi 0 1 2 3 4 int area = width * depth; 4 iload_3 1 2 3 int volume = area * height; return volume; 5 iload_2 } 6 imul 7 istore 4 9 iload 4 11ireturn 1
  • 50. Parameters and Local Variables static int volume( 0 iload_0 int width, 1 iload_1 int depth, 2 imul e int height ) are t h lum igh h pt a dt { 3 istore_3 de he vo wi 0 1 2 3 4 int area = width * depth; 4 iload_3 1 2 3 int volume = area * height; return volume; 5 iload_2 } 6 imul 7 istore 4 9 iload 4 2 11ireturn 1
  • 51. Parameters and Local Variables static int volume( 0 iload_0 int width, 1 iload_1 int depth, 2 imul e int height ) are t h lum igh h pt a dt { 3 istore_3 de he vo wi 0 1 2 3 4 int area = width * depth; 4 iload_3 1 2 3 int volume = area * height; return volume; 5 iload_2 } 6 imul 7 istore 4 9 iload 4 11ireturn 2
  • 52. Parameters and Local Variables static int volume( 0 iload_0 int width, 1 iload_1 int depth, 2 imul e int height ) are t h lum igh h pt a dt { 3 istore_3 de he vo wi 0 1 2 3 4 int area = width * depth; 4 iload_3 1 2 3 2 int volume = area * height; return volume; 5 iload_2 } 6 imul 7 istore 4 9 iload 4 11ireturn
  • 53. Parameters and Local Variables static int volume( 0 iload_0 int width, 1 iload_1 int depth, 2 imul e int height ) are t h lum igh h pt a dt { 3 istore_3 de he vo wi 0 1 2 3 4 int area = width * depth; 4 iload_3 1 2 3 2 int volume = area * height; return volume; 5 iload_2 } 6 imul 7 istore 4 9 iload 4 11ireturn 2
  • 54. Parameters and Local Variables static int volume( 0 iload_0 int width, 1 iload_1 int depth, 2 imul e int height ) are t h lum igh h pt a dt { 3 istore_3 de he vo wi 0 1 2 3 4 int area = width * depth; 4 iload_3 1 2 3 2 int volume = area * height; return volume; 5 iload_2 } 6 imul 7 istore 4 9 iload 4 3 11ireturn 2
  • 55. Parameters and Local Variables static int volume( 0 iload_0 int width, 1 iload_1 int depth, 2 imul e int height ) are t h lum igh h pt a dt { 3 istore_3 de he vo wi 0 1 2 3 4 int area = width * depth; 4 iload_3 1 2 3 2 int volume = area * height; return volume; 5 iload_2 } 6 imul 7 istore 4 9 iload 4 11ireturn 6
  • 56. Parameters and Local Variables static int volume( 0 iload_0 int width, 1 iload_1 int depth, 2 imul e int height ) are t h lum igh h pt a dt { 3 istore_3 de he vo wi 0 1 2 3 4 int area = width * depth; 4 iload_3 1 2 3 2 6 int volume = area * height; return volume; 5 iload_2 } 6 imul 7 istore 4 9 iload 4 11ireturn
  • 57. Parameters and Local Variables static int volume( 0 iload_0 int width, 1 iload_1 int depth, 2 imul e int height ) are t h lum igh h pt a dt { 3 istore_3 de he vo wi 0 1 2 3 4 int area = width * depth; 4 iload_3 1 2 3 2 6 int volume = area * height; return volume; 5 iload_2 } 6 imul 7 istore 4 9 iload 4 11ireturn 6
  • 58. Parameters and Local Variables static int volume( 0 iload_0 int width, 1 iload_1 int depth, 2 imul e int height ) are t h lum igh h pt a dt { 3 istore_3 de he vo wi 0 1 2 3 4 int area = width * depth; 4 iload_3 1 2 3 2 6 int volume = area * height; return volume; 5 iload_2 } 6 imul 7 istore 4 9 iload 4 11ireturn
  • 59. Static vs Virtual Methods static int volume( 0 iload_0 int width, 1 iload_1 int depth, 2 imul e int height ) are t he h lum h igh pt a dt { 3 istore_3 de wi vo 0 1 2 3 4 5 int area = width * depth; 4 iload_3 int volume = area * height; return volume; 5 iload_2 } 6 imul 7 istore 4 9 iload 4 11 ireturn
  • 60. Static vs Virtual Methods int volume( 0 iload_0 int width, 1 iload_1 int depth, 2 imul e int height ) are t he h lum h igh pt a dt { 3 istore_3 de wi vo 0 1 2 3 4 5 int area = width * depth; 4 iload_3 int volume = area * height; return volume; 5 iload_2 } 6 imul 7 istore 4 9 iload 4 11 ireturn
  • 61. Static vs Virtual Methods int volume( 0 iload_0 int width, 1 iload_1 int depth, 2 imul e int height ) are t he h lum h igh pt a dt s { 3 istore_3 de thi wi vo 0 1 2 3 4 5 int area = width * depth; 4 iload_3 int volume = area * height; return volume; 5 iload_2 } 6 imul 7 istore 4 9 iload 4 11 ireturn
  • 62. Static vs Virtual Methods int volume( 0 iload_1 int width, 1 iload_2 int depth, 2 imul e int height ) are t he h lum h igh pt a dt s { 3 istore 4 de thi wi vo 0 1 2 3 4 5 int area = width * depth; 5 iload 4 int volume = area * height; return volume; 7 iload_3 } 8 imul 9 istore 5 11 iload 5 13 ireturn
  • 64. Hello World System.out.println( “Hello World” ); 0 getstatic System.out 3 ldc “Hello World” 5 invokevirtual PrintStream.println 8 return
  • 65. Hello World System.out.println( “Hello World” ); 0 1 2 3 0 getstatic System.out 3 ldc “Hello World” 5 invokevirtual PrintStream.println “Hello World” 8 return System.out
  • 66. Hello World System.out.println( “Hello World” ); 0 1 2 3 0 getstatic System.out 3 ldc “Hello World” 5 invokevirtual PrintStream.println “Hello World” 8 return System.out
  • 67. Hello World System.out.println( “Hello World” ); 0 1 2 3 0 getstatic System.out 3 ldc “Hello World” 5 invokevirtual PrintStream.println “Hello World” 8 return System.out
  • 68. Hello World g s ms thi System.out.println( “Hello World” ); 0 1 2 3 0 getstatic System.out 3 ldc “Hello World” 5 invokevirtual PrintStream.println “Hello World” 8 return System.out
  • 69. Types of Method Invocations invokestatic - invoke static methods invokevirtual - invoke instance method from class invokeinterface - invoke instance method from interface invokespecial - invoke <init> / invoke super method
  • 70. New Object return new BigDecimal(“2.0”);
  • 71. New Object return new BigDecimal(“2.0”); 0 new BigDecimal 3 dup 4 ldc “2.0” 6 invokespecial BigDecimal.<init> 9 areturn
  • 72. New Object return new BigDecimal(“2.0”); 0 1 2 3 0 new BigDecimal 3 dup 4 ldc “2.0” “2.0” 6 invokespecial BigDecimal.<init> 9 areturn
  • 73. New Object return new BigDecimal(“2.0”); 0 1 2 3 0 new BigDecimal 3 dup 4 ldc “2.0” “2.0” 6 invokespecial BigDecimal.<init> 9 areturn BigDecimal
  • 74. New Object return new BigDecimal(“2.0”); 0 1 2 3 0 new BigDecimal 3 dup 4 ldc “2.0” “2.0” 6 invokespecial BigDecimal.<init> 9 areturn BigDecimal
  • 75. New Object return new BigDecimal(“2.0”); 0 1 2 3 0 new BigDecimal 3 dup 4 ldc “2.0” “2.0” 6 invokespecial BigDecimal.<init> 9 areturn BigDecimal
  • 76. New Object return new BigDecimal(“2.0”); 0 1 2 3 0 new BigDecimal 3 dup 4 ldc “2.0” “2.0” 6 invokespecial BigDecimal.<init> 9 areturn BigDecimal
  • 77. If / Else static boolean isPositive( int val ){ if ( val > 0 ) { return true; } else { return false; } }
  • 78. If / Else static boolean isPositive( int val ){ 0 iload_0 test if ( val > 0 ) { 1 ifle +5 //6 return true; 4 iconst_1 } else { if return false; 5 ireturn } 6 iconst_0 else } 7 ireturn
  • 79. If / Else static boolean isPositive( int val ){ 0 iload_0 test if ( val > 0 ) { 1 ifle +5 //6 return true; 4 iconst_1 } else { if return false; 5 ireturn } 6 iconst_0 else } 7 ireturn
  • 80. If / Else static boolean isPositive( int val ){ 0 iload_0 test if ( val > 0 ) { 1 ifle +5 //6 return true; 4 iconst_1 } else { if return false; 5 ireturn } 6 iconst_0 else } 7 ireturn
  • 81. If / Else static boolean isPositive( int val ){ 0 iload_0 test if ( val > 0 ) { 1 ifle +5 //6 return true; 4 iconst_1 } else { if return false; 5 ireturn } 6 iconst_0 else } 7 ireturn
  • 82. If / Else static boolean isPositive( int val ){ 0 iload_0 test if ( val > 0 ) { 1 ifle +5 //6 return true; 4 iconst_1 } else { if return false; 5 ireturn } 6 iconst_0 else } 7 ireturn static boolean isPositive( int val ){ return ( val > 0 ); }
  • 83. If / Else static boolean isPositive( int val ){ if ( val > 0 ) { return true; } else { return false; } } static boolean isPositive( int val ){ return ( val > 0 ); }
  • 84. If / Else static boolean isPositive( int val ){ 0 iload_0 test if ( val > 0 ) { 1 ifle +5 //6 return true; 4 iconst_1 } else { if return false; 5 ireturn } 6 iconst_0 else } 7 ireturn static boolean isPositive( int val ){ return ( val > 0 ); }
  • 85. For Loop static int sum( int min, int max ){ int sum = 0; for ( int i=min; i<max; ++i ){ sum += i; } return sum; }
  • 86. before 0 iconst_0 For Loop init & test loop 1 istore_2 2 iload_1 static int sum( int min, int max ){ 3 istore_3 int sum = 0; 4 goto +10 //14 for ( int i=min; i<max; ++i ){ 7 iload_2 loop body sum += i; 8 iload_3 } 9 iadd return sum; 10 istore_2 } inc 11 iinc 3 by 1 14 iload_3 test 15 iload_1 16 if_icmplt -9 //7 19 iload_2 after loop 20 ireturn
  • 87. before 0 iconst_0 For Loop init & test loop 1 istore_2 2 iload_1 static int sum( int min, int max ){ 3 istore_3 int sum = 0; 4 goto +10 //14 for ( int i=min; i<max; ++i ){ 7 iload_2 loop body sum += i; 8 iload_3 } 9 iadd return sum; 10 istore_2 } inc 11 iinc 3 by 1 14 iload_3 test 15 iload_1 16 if_icmplt -9 //7 19 iload_2 after loop 20 ireturn
  • 88. before 0 iconst_0 For Loop init & test loop 1 istore_2 2 iload_1 static int sum( int min, int max ){ 3 istore_3 int sum = 0; 4 goto +10 //14 for ( int i=min; i<max; ++i ){ 7 iload_2 loop body sum += i; 8 iload_3 } 9 iadd return sum; 10 istore_2 } inc 11 iinc 3 by 1 14 iload_3 test 15 iload_1 16 if_icmplt -9 //7 19 iload_2 after loop 20 ireturn
  • 89. before 0 iconst_0 For Loop init & test loop 1 istore_2 2 iload_1 static int sum( int min, int max ){ 3 istore_3 int sum = 0; 4 goto +10 //14 for ( int i=min; i<max; ++i ){ 7 iload_2 loop body sum += i; 8 iload_3 } 9 iadd return sum; 10 istore_2 } inc 11 iinc 3 by 1 14 iload_3 test 15 iload_1 16 if_icmplt -9 //7 19 iload_2 after loop 20 ireturn
  • 90. before 0 iconst_0 For Loop init & test loop 1 istore_2 2 iload_1 static int sum( int min, int max ){ 3 istore_3 int sum = 0; 4 goto +10 //14 for ( int i=min; i<max; ++i ){ 7 iload_2 loop body sum += i; 8 iload_3 } 9 iadd return sum; 10 istore_2 } inc 11 iinc 3 by 1 14 iload_3 test 15 iload_1 16 if_icmplt -9 //7 19 iload_2 after loop 20 ireturn
  • 91. before 0 iconst_0 For Loop init & test loop 1 istore_2 2 iload_1 static int sum( int min, int max ){ 3 istore_3 int sum = 0; 4 goto +10 //14 for ( int i=min; i<max; ++i ){ 7 iload_2 loop body sum += i; 8 iload_3 } 9 iadd return sum; 10 istore_2 } inc 11 iinc 3 by 1 14 iload_3 test 15 iload_1 16 if_icmplt -9 //7 19 iload_2 after loop 20 ireturn
  • 92. before 0 iconst_0 For Loop init & test loop 1 istore_2 2 iload_1 static int sum( int min, int max ){ 3 istore_3 int sum = 0; 4 goto +10 //14 for ( int i=min; i<max; ++i ){ 7 iload_2 loop body sum += i; 8 iload_3 } 9 iadd return sum; 10 istore_2 } inc 11 iinc 3 by 1 14 iload_3 test 15 iload_1 16 if_icmplt -9 //7 19 iload_2 after loop 20 ireturn
  • 93. Exception Handling static int read( InputStream in ) { try { return in.read(); } catch ( IOException e ) { return -1; } finally { IoUtils.closeQuietly( in ); } }
  • 94. 0 aload_0 Exception Handling 1 invokevirtual InputStream.read try / finally static int read( InputStream in ) { 4 istore_1 try { 5 aload_0 return in.read(); 6 invokestatic IoUtils.closeQuietly } catch ( IOException e ) { 9 iload_1 return -1; 10 ireturn } finally { 11 pop IoUtils.closeQuietly( in ); catch / finally 12 aload_0 } 13 invokestatic IoUtils.closeQuietly } 16 iconst_m1 17 ireturn 18 astore_2 19 aload_0 finally 20 invokestatic IoUtils.closeQuietly 23 aload_2 24 athrow
  • 95. 0 aload_0 Exception Handling 1 invokevirtual InputStream.read try / finally static int read( InputStream in ) { 4 istore_1 try { 5 aload_0 return in.read(); 6 invokestatic IoUtils.closeQuietly } catch ( IOException e ) { 9 iload_1 return -1; 10 ireturn } finally { 11 pop IoUtils.closeQuietly( in ); catch / finally 12 aload_0 } 13 invokestatic IoUtils.closeQuietly } 16 iconst_m1 17 ireturn 18 astore_2 19 aload_0 finally 20 invokestatic IoUtils.closeQuietly 23 aload_2 24 athrow
  • 96. 0 aload_0 Exception Handling 1 invokevirtual InputStream.read try / finally static int read( InputStream in ) { 4 istore_1 try { 5 aload_0 return in.read(); 6 invokestatic IoUtils.closeQuietly } catch ( IOException e ) { 9 iload_1 return -1; 10 ireturn } finally { 11 pop IoUtils.closeQuietly( in ); catch / finally 12 aload_0 } 13 invokestatic IoUtils.closeQuietly } 16 iconst_m1 17 ireturn Exception Table 18 astore_2 start end handler Exception 19 aload_0 0 5 11 IOException finally 20 invokestatic IoUtils.closeQuietly 0 5 18 any 23 aload_2 11 12 18 any 24 athrow
  • 97. 0 aload_0 Exception Handling 1 invokevirtual InputStream.read try / finally static int read( InputStream in ) { 4 istore_1 try { 5 aload_0 return in.read(); 6 invokestatic IoUtils.closeQuietly } catch ( IOException e ) { 9 iload_1 return -1; 10 ireturn } finally { 11 pop IoUtils.closeQuietly( in ); catch / finally 12 aload_0 } 13 invokestatic IoUtils.closeQuietly } 16 iconst_m1 17 ireturn Exception Table 18 astore_2 start end handler Exception 19 aload_0 0 5 11 IOException finally 20 invokestatic IoUtils.closeQuietly 0 5 18 any 23 aload_2 11 12 18 any 24 athrow
  • 98. More Attributes... Java 1.2+ InnerClass Synthetic Deprecated
  • 99. More Attributes... Java 1.2+ InnerClass Synthetic Deprecated Debugging LineNumberTable LocalVariableTable SourceFile
  • 100. More Attributes... Java 1.2+ Java 5+ InnerClass Signature Synthetic RuntimeVisibleAnnotations Deprecated RuntimeInvisibleAnnotations Debugging LineNumberTable LocalVariableTable SourceFile
  • 102. Resources The Java Virtual Machine Specification http://java.sun.com/docs/books/jvms/ JClassLib Viewer http://www.ej-technologies.com/products/jclasslib/ overview.html Maxine VM http://labs.oracle.com/projects/maxine/ New Features in Java 6 - Annotation Processing http://www.javabeat.net/articles/14-java-60-features- part-2-pluggable-annotation-proce-1.html