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Java example source code file (ObjectReader.java)

This example Java source code file (ObjectReader.java) is included in the alvinalexander.com "Java Source Code Warehouse" project. The intent of this project is to help you "Learn Java by Example" TM.

Learn more about this Java project at its project page.

Java - Java tags/keywords

class, classnotfoundexception, debug, defaultoopvisitor, entry, exception, indexablefieldidentifier, instanceklass, object, oopfield, reflection, runtimeexception, string, symbol, typearrayklass, util

The ObjectReader.java Java example source code

/*
 * Copyright (c) 2002, 2012, Oracle and/or its affiliates. All rights reserved.
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
 *
 * This code is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2 only, as
 * published by the Free Software Foundation.
 *
 * This code is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
 * version 2 for more details (a copy is included in the LICENSE file that
 * accompanied this code).
 *
 * You should have received a copy of the GNU General Public License version
 * 2 along with this work; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
 *
 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
 * or visit www.oracle.com if you need additional information or have any
 * questions.
 *
 */

package sun.jvm.hotspot.utilities;

import java.lang.reflect.Modifier;
import java.util.*;
import sun.jvm.hotspot.debugger.*;
import sun.jvm.hotspot.oops.*;
import sun.jvm.hotspot.runtime.*;
import sun.jvm.hotspot.utilities.*;

/**
 * ObjectReader can "deserialize" objects from debuggee.
 *
 * Class Loading:
 *
 * ObjectReader loads classes using the given class loader. If no
 * class loader is supplied, it uses a ProcImageClassLoader, which
 * loads classes from debuggee core or process.

 * Object creation:
 *
 * This class uses no-arg constructor to construct objects. But if
 * there is no no-arg constructor in a given class, then it tries to
 * use other constructors with 'default' values - null for object
 * types, 0, 0.0, false etc. for primitives.  If this process fails to
 * construct an instance (because of null checking by constructor or 0
 * being invalid for an int arg etc.), then null is returned. While
 * constructing complete object graph 'null' is inserted silently on
 * failure and the deserialization continues to construct best-effort
 * object graph.
 *
 * Debug messages:
 *
 * The flag sun.jvm.hotspot.utilities.ObjectReader.DEBUG may be set to
 * non-null to get debug error messages and stack traces.
 *
 * JDK version:
 *
 * JDK classes are loaded by bootstrap class loader and not by the
 * supplied class loader or ProcImageClassLoader. This may create
 * problems if a JDK class evolves. i.e., if SA runs a JDK version
 * different from that of the debuggee, there is a possibility of
 * schema change. It is recommended that the matching JDK version be
 * used to run SA for proper object deserialization.
 *
 */

public class ObjectReader {

   private static final boolean DEBUG;
   static {
      DEBUG = System.getProperty("sun.jvm.hotspot.utilities.ObjectReader.DEBUG") != null;
   }

   public ObjectReader(ClassLoader cl) {
      this.cl = cl;
      this.oopToObjMap = new HashMap();
      this.fieldMap = new HashMap();
   }

   public ObjectReader() {
      this(new ProcImageClassLoader());
   }

   static void debugPrintln(String msg) {
      if (DEBUG) {
         System.err.println("DEBUG>" + msg);
      }
   }

   static void debugPrintStackTrace(Exception exp) {
      if (DEBUG) {
         StackTraceElement[] els = exp.getStackTrace();
         for (int i = 0; i < els.length; i++) {
            System.err.println("DEBUG>" + els[i].toString());
         }
      }
   }

   public Object readObject(Oop oop) throws ClassNotFoundException {
      if (oop instanceof Instance) {
         return readInstance((Instance) oop);
      } else if (oop instanceof TypeArray){
         return readPrimitiveArray((TypeArray)oop);
      } else if (oop instanceof ObjArray){
         return readObjectArray((ObjArray)oop);
      } else {
         return null;
      }
   }

   protected final Object getDefaultPrimitiveValue(Class clz) {
      if (clz == Boolean.TYPE) {
         return Boolean.FALSE;
      } else if (clz == Character.TYPE) {
         return new Character(' ');
      } else if (clz == Byte.TYPE) {
         return new Byte((byte) 0);
      } else if (clz == Short.TYPE) {
         return new Short((short) 0);
      } else if (clz == Integer.TYPE) {
         return new Integer(0);
      } else if (clz == Long.TYPE) {
         return new Long(0L);
      } else if (clz == Float.TYPE) {
         return new Float(0.0f);
      } else if (clz == Double.TYPE) {
         return new Double(0.0);
      } else {
         throw new RuntimeException("should not reach here!");
      }
   }

   protected Symbol javaLangString;
   protected Symbol javaUtilHashtableEntry;
   protected Symbol javaUtilHashtable;
   protected Symbol javaUtilProperties;

   protected Symbol getVMSymbol(String name) {
      return VM.getVM().getSymbolTable().probe(name);
   }

   protected Symbol javaLangString() {
      if (javaLangString == null) {
         javaLangString = getVMSymbol("java/lang/String");
      }
      return javaLangString;
   }

   protected Symbol javaUtilHashtableEntry() {
      if (javaUtilHashtableEntry == null) {
         javaUtilHashtableEntry = getVMSymbol("java/util/Hashtable$Entry");
      }
      return javaUtilHashtableEntry;
   }

   protected Symbol javaUtilHashtable() {
      if (javaUtilHashtable == null) {
         javaUtilHashtable = getVMSymbol("java/util/Hashtable");
      }
      return javaUtilHashtable;
   }

   protected Symbol javaUtilProperties() {
      if (javaUtilProperties == null) {
         javaUtilProperties = getVMSymbol("java/util/Properties");
      }
      return javaUtilProperties;
   }

   private void setHashtableEntry(java.util.Hashtable p, Oop oop) {
      InstanceKlass ik = (InstanceKlass)oop.getKlass();
      OopField keyField = (OopField)ik.findField("key", "Ljava/lang/Object;");
      OopField valueField = (OopField)ik.findField("value", "Ljava/lang/Object;");
      OopField nextField = (OopField)ik.findField("next", "Ljava/util/Hashtable$Entry;");
      if (DEBUG) {
         if (Assert.ASSERTS_ENABLED) {
            Assert.that(ik.getName().equals(javaUtilHashtableEntry()), "Not a Hashtable$Entry?");
            Assert.that(keyField != null && valueField != null && nextField != null, "Invalid fields!");
         }
      }

      Object key = null;
      Object value = null;
      Oop next = null;
      try {
         key = readObject(keyField.getValue(oop));
         value = readObject(valueField.getValue(oop));
         next =  (Oop)nextField.getValue(oop);
         // For Properties, should use setProperty(k, v). Since it only runs in SA
         // using put(k, v) should be OK.
         p.put(key, value);
         if (next != null) {
            setHashtableEntry(p, next);
         }
      } catch (ClassNotFoundException ce) {
         if( DEBUG) {
            debugPrintln("Class not found " + ce);
            debugPrintStackTrace(ce);
         }
      }
   }

   protected Object getHashtable(Instance oop, boolean isProperties) {
      InstanceKlass k = (InstanceKlass)oop.getKlass();
      OopField tableField = (OopField)k.findField("table", "[Ljava/util/Hashtable$Entry;");
      if (tableField == null) {
         debugPrintln("Could not find field of [Ljava/util/Hashtable$Entry;");
         return null;
      }
      java.util.Hashtable table = (isProperties) ? new java.util.Properties()
                                                 : new java.util.Hashtable();
      ObjArray kvs = (ObjArray)tableField.getValue(oop);
      long size = kvs.getLength();
      debugPrintln("Hashtable$Entry Size = " + size);
      for (long i=0; i<size; i++) {
         Oop entry = kvs.getObjAt(i);
         if (entry != null && entry.isInstance()) {
            setHashtableEntry(table, entry);
         }
      }
      return table;
   }

   public Object readInstance(Instance oop) throws ClassNotFoundException {
      Object result = getFromObjTable(oop);
      if (result == null) {
         InstanceKlass kls = (InstanceKlass) oop.getKlass();
         // Handle java.lang.String instances differently. As part of JSR-133, fields of immutable
         // classes have been made final. The algorithm below will not be able to read Strings from
         // debuggee (can't use reflection to set final fields). But, need to read Strings is very
         // important.
         // Same for Hashtable, key and hash are final, could not be set in the algorithm too.
         // FIXME: need a framework to handle many other special cases.
         if (kls.getName().equals(javaLangString())) {
            return OopUtilities.stringOopToString(oop);
         }

         if (kls.getName().equals(javaUtilHashtable())) {
            return getHashtable(oop, false);
         }

         if (kls.getName().equals(javaUtilProperties())) {
            return getHashtable(oop, true);
         }

         Class clz = readClass(kls);
         try {
            result = clz.newInstance();
         } catch (Exception ex) {
            // no-arg constructor failed to create object. Let us try
            // to call constructors one-by-one with default arguments
            // (null for objects, 0/0.0 etc. for primitives) till we
            // succeed or fail on all constructors.

            java.lang.reflect.Constructor[] ctrs = clz.getDeclaredConstructors();
            for (int n = 0; n < ctrs.length; n++) {
               java.lang.reflect.Constructor c = ctrs[n];
               Class[] paramTypes = c.getParameterTypes();
               Object[] params = new Object[paramTypes.length];
               for (int i = 0; i < params.length; i++) {
                  if (paramTypes[i].isPrimitive()) {
                     params[i] = getDefaultPrimitiveValue(paramTypes[i]);
                  }
               }
               try {
                  c.setAccessible(true);
                  result = c.newInstance(params);
                  break;
               } catch (Exception exp) {
                  if (DEBUG) {
                     debugPrintln("Can't create object using " + c);
                     debugPrintStackTrace(exp);
                  }
               }
            }
         }

         if (result != null) {
            putIntoObjTable(oop, result);
            oop.iterate(new FieldSetter(result), false);
         }
      }
      return result;
   }

   public Object readPrimitiveArray(final TypeArray array) {

      Object result = getFromObjTable(array);
      if (result == null) {
         int length = (int) array.getLength();
         TypeArrayKlass klass = (TypeArrayKlass) array.getKlass();
         int type = (int) klass.getElementType();
         switch (type) {
            case TypeArrayKlass.T_BOOLEAN: {
               final boolean[] arrayObj = new boolean[length];
               array.iterate(new DefaultOopVisitor() {
                                public void doBoolean(BooleanField field, boolean isVMField) {
                                   IndexableFieldIdentifier ifd = (IndexableFieldIdentifier) field.getID();
                                   arrayObj[ifd.getIndex()] = field.getValue(array);
                                }
                            }, false);
               result = arrayObj;
               }
               break;

            case TypeArrayKlass.T_CHAR: {
               final char[] arrayObj = new char[length];
               array.iterate(new DefaultOopVisitor() {
                                public void doChar(CharField field, boolean isVMField) {
                                   IndexableFieldIdentifier ifd = (IndexableFieldIdentifier) field.getID();
                                   arrayObj[ifd.getIndex()] = field.getValue(array);
                                }
                            }, false);
               result = arrayObj;
               }
               break;

            case TypeArrayKlass.T_FLOAT: {
               final float[] arrayObj = new float[length];
               array.iterate(new DefaultOopVisitor() {
                                public void doFloat(FloatField field, boolean isVMField) {
                                   IndexableFieldIdentifier ifd = (IndexableFieldIdentifier) field.getID();
                                   arrayObj[ifd.getIndex()] = field.getValue(array);
                                }
                            }, false);
               result = arrayObj;
               }
               break;

            case TypeArrayKlass.T_DOUBLE: {
               final double[] arrayObj = new double[length];
               array.iterate(new DefaultOopVisitor() {
                                public void doDouble(DoubleField field, boolean isVMField) {
                                   IndexableFieldIdentifier ifd = (IndexableFieldIdentifier) field.getID();
                                   arrayObj[ifd.getIndex()] = field.getValue(array);
                                }
                            }, false);
               result = arrayObj;
               }
               break;

            case TypeArrayKlass.T_BYTE: {
               final byte[] arrayObj = new byte[length];
               array.iterate(new DefaultOopVisitor() {
                                public void doByte(ByteField field, boolean isVMField) {
                                   IndexableFieldIdentifier ifd = (IndexableFieldIdentifier) field.getID();
                                   arrayObj[ifd.getIndex()] = field.getValue(array);
                                }
                            }, false);
               result = arrayObj;
               }
               break;

            case TypeArrayKlass.T_SHORT: {
               final short[] arrayObj = new short[length];
               array.iterate(new DefaultOopVisitor() {
                                public void doShort(ShortField field, boolean isVMField) {
                                   IndexableFieldIdentifier ifd = (IndexableFieldIdentifier) field.getID();
                                   arrayObj[ifd.getIndex()] = field.getValue(array);
                                }
                            }, false);
               result = arrayObj;
               }
               break;

            case TypeArrayKlass.T_INT: {
               final int[] arrayObj = new int[length];
               array.iterate(new DefaultOopVisitor() {
                                public void doInt(IntField field, boolean isVMField) {
                                   IndexableFieldIdentifier ifd = (IndexableFieldIdentifier) field.getID();
                                   arrayObj[ifd.getIndex()] = field.getValue(array);
                                }
                            }, false);
               result = arrayObj;
               }
               break;

            case TypeArrayKlass.T_LONG: {
               final long[] arrayObj = new long[length];
               array.iterate(new DefaultOopVisitor() {
                                public void doLong(LongField field, boolean isVMField) {
                                   IndexableFieldIdentifier ifd = (IndexableFieldIdentifier) field.getID();
                                   arrayObj[ifd.getIndex()] = field.getValue(array);
                                }
                            }, false);
               result = arrayObj;
               }
               break;

            default:
               throw new RuntimeException("should not reach here!");
         }

         putIntoObjTable(array, result);
      }
      return result;
   }

   protected final boolean isRobust(OopHandle handle) {
      return RobustOopDeterminator.oopLooksValid(handle);
   }

   public Object readObjectArray(final ObjArray array) throws ClassNotFoundException {
       Object result = getFromObjTable(array);
       if (result == null) {
          int length = (int) array.getLength();
          ObjArrayKlass klass = (ObjArrayKlass) array.getKlass();
          Klass bottomKls = klass.getBottomKlass();
          Class bottomCls = null;
          final int dimension = (int) klass.getDimension();
          int[] dimArray = null;
          if (bottomKls instanceof InstanceKlass) {
             bottomCls = readClass((InstanceKlass) bottomKls);
             dimArray = new int[dimension];
          } else { // instanceof TypeArrayKlass
             TypeArrayKlass botKls = (TypeArrayKlass) bottomKls;
             dimArray = new int[dimension -1];
          }
          // initialize the length
          dimArray[0] = length;
          final Object[] arrayObj = (Object[]) java.lang.reflect.Array.newInstance(bottomCls, dimArray);
          putIntoObjTable(array, arrayObj);
          result = arrayObj;
          array.iterate(new DefaultOopVisitor() {
                               public void doOop(OopField field, boolean isVMField) {
                                  OopHandle handle = field.getValueAsOopHandle(getObj());
                                  if (! isRobust(handle)) {
                                     return;
                                  }

                                  IndexableFieldIdentifier ifd = (IndexableFieldIdentifier) field.getID();
                                  try {
                                     arrayObj[ifd.getIndex()] = readObject(field.getValue(getObj()));
                                  } catch (Exception e) {
                                     if (DEBUG) {
                                        debugPrintln("Array element set failed for " + ifd);
                                        debugPrintStackTrace(e);
                                     }
                                  }
                               }
                        }, false);
       }
       return result;
   }

   protected class FieldSetter extends DefaultOopVisitor {
      protected Object obj;

      public FieldSetter(Object obj) {
         this.obj = obj;
      }

      private void printFieldSetError(java.lang.reflect.Field f, Exception ex) {
         if (DEBUG) {
            if (f != null) debugPrintln("Field set failed for " + f);
            debugPrintStackTrace(ex);
         }
      }

      // Callback methods for each field type in an object
      public void doOop(OopField field, boolean isVMField) {
         OopHandle handle = field.getValueAsOopHandle(getObj());
         if (! isRobust(handle) ) {
            return;
         }

         java.lang.reflect.Field f = null;
         try {
            f = readField(field);
            if (Modifier.isFinal(f.getModifiers())) return;
            f.setAccessible(true);
            f.set(obj, readObject(field.getValue(getObj())));
         } catch (Exception ex) {
            printFieldSetError(f, ex);
         }
      }

      public void doByte(ByteField field, boolean isVMField) {
         java.lang.reflect.Field f = null;
         try {
            f = readField(field);
            if (Modifier.isFinal(f.getModifiers())) return;
            f.setAccessible(true);
            f.setByte(obj, field.getValue(getObj()));
         } catch (Exception ex) {
            printFieldSetError(f, ex);
         }
      }

      public void doChar(CharField field, boolean isVMField) {
         java.lang.reflect.Field f = null;
         try {
            f = readField(field);
            if (Modifier.isFinal(f.getModifiers())) return;
            f.setAccessible(true);
            f.setChar(obj, field.getValue(getObj()));
         } catch (Exception ex) {
            printFieldSetError(f, ex);
         }
      }

      public void doBoolean(BooleanField field, boolean isVMField) {
         java.lang.reflect.Field f = null;
         try {
            f = readField(field);
            if (Modifier.isFinal(f.getModifiers())) return;
            f.setAccessible(true);
            f.setBoolean(obj, field.getValue(getObj()));
         } catch (Exception ex) {
            printFieldSetError(f, ex);
         }
      }

      public void doShort(ShortField field, boolean isVMField) {
         java.lang.reflect.Field f = null;
         try {
            f = readField(field);
            if (Modifier.isFinal(f.getModifiers())) return;
            f.setAccessible(true);
            f.setShort(obj, field.getValue(getObj()));
         } catch (Exception ex) {
            printFieldSetError(f, ex);
         }
      }

      public void doInt(IntField field, boolean isVMField) {
         java.lang.reflect.Field f = null;
         try {
            f = readField(field);
            if (Modifier.isFinal(f.getModifiers())) return;
            f.setAccessible(true);
            f.setInt(obj, field.getValue(getObj()));
         } catch (Exception ex) {
            printFieldSetError(f, ex);
         }
      }

      public void doLong(LongField field, boolean isVMField) {
         java.lang.reflect.Field f = null;
         try {
            f = readField(field);
            if (Modifier.isFinal(f.getModifiers())) return;
            f.setAccessible(true);
            f.setLong(obj, field.getValue(getObj()));
         } catch (Exception ex) {
            printFieldSetError(f, ex);
         }
      }

      public void doFloat(FloatField field, boolean isVMField) {
         java.lang.reflect.Field f = null;
         try {
            f = readField(field);
            if (Modifier.isFinal(f.getModifiers())) return;
            f.setAccessible(true);
            f.setFloat(obj, field.getValue(getObj()));
         } catch (Exception ex) {
            printFieldSetError(f, ex);
         }
      }

      public void doDouble(DoubleField field, boolean isVMField) {
         java.lang.reflect.Field f = null;
         try {
            f = readField(field);
            if (Modifier.isFinal(f.getModifiers())) return;
            f.setAccessible(true);
            f.setDouble(obj, field.getValue(getObj()));
         } catch (Exception ex) {
            printFieldSetError(f, ex);
         }
      }

      public void doCInt(CIntField field, boolean isVMField) {
         throw new RuntimeException("should not reach here!");
      }
   }

   public Class readClass(InstanceKlass kls) throws ClassNotFoundException {
      Class cls = (Class) getFromObjTable(kls);
      if (cls == null) {
         cls = Class.forName(kls.getName().asString().replace('/', '.'), true, cl);
         putIntoObjTable(kls, cls);
      }
      return cls;
   }

   public Object readMethodOrConstructor(sun.jvm.hotspot.oops.Method m)
                     throws NoSuchMethodException, ClassNotFoundException {
      String name = m.getName().asString();
      if (name.equals("<init>")) {
         return readConstructor(m);
      } else {
         return readMethod(m);
      }
   }

   public java.lang.reflect.Method readMethod(sun.jvm.hotspot.oops.Method m)
            throws NoSuchMethodException, ClassNotFoundException {
      java.lang.reflect.Method result = (java.lang.reflect.Method) getFromObjTable(m);
      if (result == null) {
         Class clz = readClass((InstanceKlass)m.getMethodHolder());
         String name = m.getName().asString();
         Class[] paramTypes = getParamTypes(m.getSignature());
         result = clz.getMethod(name, paramTypes);
         putIntoObjTable(m, result);
      }
      return result;
   }

   public java.lang.reflect.Constructor readConstructor(sun.jvm.hotspot.oops.Method m)
            throws NoSuchMethodException, ClassNotFoundException {
      java.lang.reflect.Constructor result = (java.lang.reflect.Constructor) getFromObjTable(m);
      if (result == null) {
         Class clz = readClass((InstanceKlass)m.getMethodHolder());
         String name = m.getName().asString();
         Class[] paramTypes = getParamTypes(m.getSignature());
         result = clz.getDeclaredConstructor(paramTypes);
         putIntoObjTable(m, result);
      }
      return result;
   }

   public java.lang.reflect.Field readField(sun.jvm.hotspot.oops.Field f)
            throws NoSuchFieldException, ClassNotFoundException {
      java.lang.reflect.Field result = (java.lang.reflect.Field) fieldMap.get(f);
      if (result == null) {
         FieldIdentifier fieldId = f.getID();
         Class clz = readClass((InstanceKlass) f.getFieldHolder());
         String name = fieldId.getName();
         try {
            result = clz.getField(name);
         } catch (NoSuchFieldException nsfe) {
            result = clz.getDeclaredField(name);
         }
         fieldMap.put(f, result);
      }
      return result;
   }

   protected final ClassLoader cl;
   protected Map   oopToObjMap; // Map<Oop, Object>
   protected Map   fieldMap;    // Map<sun.jvm.hotspot.oops.Field, java.lang.reflect.Field>

   protected void putIntoObjTable(Oop oop, Object obj) {
      oopToObjMap.put(oop, obj);
   }

   protected Object getFromObjTable(Oop oop) {
      return oopToObjMap.get(oop);
   }

   protected void putIntoObjTable(Metadata oop, Object obj) {
      oopToObjMap.put(oop, obj);
   }

   protected Object getFromObjTable(Metadata oop) {
      return oopToObjMap.get(oop);
   }

   protected class SignatureParser extends SignatureIterator {
      protected Vector tmp = new Vector(); // Vector<Class>

      public SignatureParser(Symbol s) {
         super(s);
      }

      public void doBool  () { tmp.add(Boolean.TYPE);    }
      public void doChar  () { tmp.add(Character.TYPE);  }
      public void doFloat () { tmp.add(Float.TYPE);      }
      public void doDouble() { tmp.add(Double.TYPE);     }
      public void doByte  () { tmp.add(Byte.TYPE);       }
      public void doShort () { tmp.add(Short.TYPE);      }
      public void doInt   () { tmp.add(Integer.TYPE);    }
      public void doLong  () { tmp.add(Long.TYPE);       }
      public void doVoid  () {
         if(isReturnType()) {
            tmp.add(Void.TYPE);
         } else {
            throw new RuntimeException("should not reach here");
         }
      }

      public void doObject(int begin, int end) {
         tmp.add(getClass(begin, end));
      }

      public void doArray (int begin, int end) {
        int inner = arrayInnerBegin(begin);
        Class elemCls = null;
        switch (_signature.getByteAt(inner)) {
        case 'B': elemCls = Boolean.TYPE; break;
        case 'C': elemCls = Character.TYPE; break;
        case 'D': elemCls = Double.TYPE; break;
        case 'F': elemCls = Float.TYPE; break;
        case 'I': elemCls = Integer.TYPE; break;
        case 'J': elemCls = Long.TYPE; break;
        case 'S': elemCls = Short.TYPE; break;
        case 'Z': elemCls = Boolean.TYPE; break;
        case 'L': elemCls = getClass(inner + 1, end); break;
        default: break;
        }

        int dimension = inner - begin;
        // create 0 x 0 ... array and get class from that
        int[] dimArray = new int[dimension];
        tmp.add(java.lang.reflect.Array.newInstance(elemCls, dimArray).getClass());
      }

      protected Class getClass(int begin, int end) {
         String className = getClassName(begin, end);
         try {
            return Class.forName(className, true, cl);
         } catch (Exception e) {
            if (DEBUG) {
               debugPrintln("Can't load class " + className);
            }
            throw new RuntimeException(e);
         }
      }

      protected String getClassName(int begin, int end) {
         StringBuffer buf = new StringBuffer();
         for (int i = begin; i < end; i++) {
            char c = (char) (_signature.getByteAt(i) & 0xFF);
            if (c == '/') {
               buf.append('.');
            } else {
               buf.append(c);
            }
         }
         return buf.toString();
      }

      protected int arrayInnerBegin(int begin) {
         while (_signature.getByteAt(begin) == '[') {
           ++begin;
         }
         return begin;
      }

      public int getNumParams() {
         return tmp.size();
      }

      public Enumeration getParamTypes() {
         return tmp.elements();
      }
   }

   protected Class[] getParamTypes(Symbol signature) {
      SignatureParser sp = new SignatureParser(signature);
      sp.iterateParameters();
      Class result[] = new Class[sp.getNumParams()];
      Enumeration e = sp.getParamTypes();
      int i = 0;
      while (e.hasMoreElements()) {
         result[i] = (Class) e.nextElement();
         i++;
      }
      return result;
   }
}

Other Java examples (source code examples)

Here is a short list of links related to this Java ObjectReader.java source code file:

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