Java tutorial
/* * Copyright 2012 The Netty Project * * The Netty Project licenses this file to you under the Apache License, * version 2.0 (the "License"); you may not use this file except in compliance * with the License. You may obtain a copy of the License at: * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the * License for the specific language governing permissions and limitations * under the License. */ package io.netty.handler.codec.serialization; import io.netty.util.internal.ObjectUtil; import java.io.BufferedReader; import java.io.DataInputStream; import java.io.IOException; import java.io.InputStream; import java.io.ObjectInput; import java.io.StreamCorruptedException; /** * An {@link ObjectInput} which is interoperable with {@link ObjectEncoder} * and {@link ObjectEncoderOutputStream}. */ public class ObjectDecoderInputStream extends InputStream implements ObjectInput { private final DataInputStream in; private final int maxObjectSize; private final ClassResolver classResolver; /** * Creates a new {@link ObjectInput}. * * @param in * the {@link InputStream} where the serialized form will be * read from */ public ObjectDecoderInputStream(InputStream in) { this(in, null); } /** * Creates a new {@link ObjectInput}. * * @param in * the {@link InputStream} where the serialized form will be * read from * @param classLoader * the {@link ClassLoader} which will load the class of the * serialized object */ public ObjectDecoderInputStream(InputStream in, ClassLoader classLoader) { this(in, classLoader, 1048576); } /** * Creates a new {@link ObjectInput}. * * @param in * the {@link InputStream} where the serialized form will be * read from * @param maxObjectSize * the maximum byte length of the serialized object. if the length * of the received object is greater than this value, * a {@link StreamCorruptedException} will be raised. */ public ObjectDecoderInputStream(InputStream in, int maxObjectSize) { this(in, null, maxObjectSize); } /** * Creates a new {@link ObjectInput}. * * @param in * the {@link InputStream} where the serialized form will be * read from * @param classLoader * the {@link ClassLoader} which will load the class of the * serialized object * @param maxObjectSize * the maximum byte length of the serialized object. if the length * of the received object is greater than this value, * a {@link StreamCorruptedException} will be raised. */ public ObjectDecoderInputStream(InputStream in, ClassLoader classLoader, int maxObjectSize) { ObjectUtil.checkNotNull(in, "in"); ObjectUtil.checkPositive(maxObjectSize, "maxObjectSize"); if (in instanceof DataInputStream) { this.in = (DataInputStream) in; } else { this.in = new DataInputStream(in); } classResolver = ClassResolvers.weakCachingResolver(classLoader); this.maxObjectSize = maxObjectSize; } @Override public Object readObject() throws ClassNotFoundException, IOException { int dataLen = readInt(); if (dataLen <= 0) { throw new StreamCorruptedException("invalid data length: " + dataLen); } if (dataLen > maxObjectSize) { throw new StreamCorruptedException("data length too big: " + dataLen + " (max: " + maxObjectSize + ')'); } return new CompactObjectInputStream(in, classResolver).readObject(); } @Override public int available() throws IOException { return in.available(); } @Override public void close() throws IOException { in.close(); } @Override public void mark(int readlimit) { in.mark(readlimit); } @Override public boolean markSupported() { return in.markSupported(); } @Override public int read() throws IOException { return in.read(); } @Override public final int read(byte[] b, int off, int len) throws IOException { return in.read(b, off, len); } @Override public final int read(byte[] b) throws IOException { return in.read(b); } @Override public final boolean readBoolean() throws IOException { return in.readBoolean(); } @Override public final byte readByte() throws IOException { return in.readByte(); } @Override public final char readChar() throws IOException { return in.readChar(); } @Override public final double readDouble() throws IOException { return in.readDouble(); } @Override public final float readFloat() throws IOException { return in.readFloat(); } @Override public final void readFully(byte[] b, int off, int len) throws IOException { in.readFully(b, off, len); } @Override public final void readFully(byte[] b) throws IOException { in.readFully(b); } @Override public final int readInt() throws IOException { return in.readInt(); } /** * @deprecated Use {@link BufferedReader#readLine()} instead. */ @Override @Deprecated public final String readLine() throws IOException { return in.readLine(); } @Override public final long readLong() throws IOException { return in.readLong(); } @Override public final short readShort() throws IOException { return in.readShort(); } @Override public final int readUnsignedByte() throws IOException { return in.readUnsignedByte(); } @Override public final int readUnsignedShort() throws IOException { return in.readUnsignedShort(); } @Override public final String readUTF() throws IOException { return in.readUTF(); } @Override public void reset() throws IOException { in.reset(); } @Override public long skip(long n) throws IOException { return in.skip(n); } @Override public final int skipBytes(int n) throws IOException { return in.skipBytes(n); } }