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Diffstat (limited to 'kamon-autoweave/src/main/java/com/sun/tools/attach/VirtualMachineDescriptor.java')
| -rw-r--r-- | kamon-autoweave/src/main/java/com/sun/tools/attach/VirtualMachineDescriptor.java | 208 |
1 files changed, 208 insertions, 0 deletions
diff --git a/kamon-autoweave/src/main/java/com/sun/tools/attach/VirtualMachineDescriptor.java b/kamon-autoweave/src/main/java/com/sun/tools/attach/VirtualMachineDescriptor.java new file mode 100644 index 00000000..6459e806 --- /dev/null +++ b/kamon-autoweave/src/main/java/com/sun/tools/attach/VirtualMachineDescriptor.java @@ -0,0 +1,208 @@ +/* + * Copyright 2005-2006 Sun Microsystems, Inc. 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. Sun designates this + * particular file as subject to the "Classpath" exception as provided + * by Sun in the LICENSE file that accompanied this code. + * + * 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 Sun Microsystems, Inc., 4150 Network Circle, Santa Clara, + * CA 95054 USA or visit www.sun.com if you need additional information or + * have any questions. + */ +package com.sun.tools.attach; + +import com.sun.tools.attach.spi.AttachProvider; + +/** + * Describes a Java virtual machine. + * <p/> + * <p> A <code>VirtualMachineDescriptor</code> is a container class used to + * describe a Java virtual machine. It encapsulates an identifier that identifies + * a target virtual machine, and a reference to the {@link + * com.sun.tools.attach.spi.AttachProvider AttachProvider} that should be used + * when attempting to attach to the virtual machine. The identifier is + * implementation-dependent but is typically the process identifier (or pid) + * environments where each Java virtual machine runs in its own operating system + * process. </p> + * <p/> + * <p> A <code>VirtualMachineDescriptor</code> also has a {@link #displayName() displayName}. + * The display name is typically a human readable string that a tool might + * display to a user. For example, a tool that shows a list of Java + * virtual machines running on a system might use the display name rather + * than the identifier. A <code>VirtualMachineDescriptor</code> may be + * created without a <i>display name</i>. In that case the identifier is + * used as the <i>display name</i>. + * <p/> + * <p> <code>VirtualMachineDescriptor</code> instances are typically created by + * invoking the {@link VirtualMachine#list VirtualMachine.list()} + * method. This returns the complete list of descriptors to describe the + * Java virtual machines known to all installed {@link + * com.sun.tools.attach.spi.AttachProvider attach providers}. + * + * @since 1.6 + */ +public final class VirtualMachineDescriptor +{ + private AttachProvider provider; + private String id; + private String displayName; + + private volatile int hash; // 0 => not computed + + /** + * Creates a virtual machine descriptor from the given components. + * + * @param provider The AttachProvider to attach to the Java virtual machine. + * @param id The virtual machine identifier. + * @param displayName The display name. + * @throws NullPointerException If any of the arguments are <code>null</code> + */ + public VirtualMachineDescriptor(AttachProvider provider, String id, String displayName) + { + if (provider == null) { + throw new NullPointerException("provider cannot be null"); + } + + if (id == null) { + throw new NullPointerException("identifier cannot be null"); + } + + if (displayName == null) { + throw new NullPointerException("display name cannot be null"); + } + + this.provider = provider; + this.id = id; + this.displayName = displayName; + } + + /** + * Creates a virtual machine descriptor from the given components. + * <p/> + * <p> This convenience constructor works as if by invoking the + * three-argument constructor as follows: + * <p/> + * <blockquote><tt> + * new {@link #VirtualMachineDescriptor(com.sun.tools.attach.spi.AttachProvider, String, String) + * VirtualMachineDescriptor}(provider, id, id); + * </tt></blockquote> + * <p/> + * <p> That is, it creates a virtual machine descriptor such that + * the <i>display name</i> is the same as the virtual machine + * identifier. + * + * @param provider The AttachProvider to attach to the Java virtual machine. + * @param id The virtual machine identifier. + * @throws NullPointerException If <tt>provider</tt> or <tt>id</tt> is <tt>null</tt>. + */ + public VirtualMachineDescriptor(AttachProvider provider, String id) + { + this(provider, id, id); + } + + /** + * Return the <code>AttachProvider</code> that this descriptor references. + * + * @return The <code>AttachProvider</code> that this descriptor references. + */ + public AttachProvider provider() + { + return provider; + } + + /** + * Return the identifier component of this descriptor. + * + * @return The identifier component of this descriptor. + */ + public String id() + { + return id; + } + + /** + * Return the <i>display name</i> component of this descriptor. + * + * @return The display name component of this descriptor. + */ + public String displayName() + { + return displayName; + } + + /** + * Returns a hash-code value for this VirtualMachineDescriptor. The hash + * code is based upon the descriptor's components, and satisfies + * the general contract of the Object.hashCode method. + * + * @return A hash-code value for this descriptor. + */ + public int hashCode() + { + if (hash != 0) { + return hash; + } + + hash = provider.hashCode() * 127 + id.hashCode(); + return hash; + } + + /** + * Tests this VirtualMachineDescriptor for equality with another object. + * <p/> + * <p> If the given object is not a VirtualMachineDescriptor then this + * method returns <tt>false</tt>. For two VirtualMachineDescriptors to + * be considered equal requires that they both reference the same + * provider, and their {@link #id() identifiers} are equal. </p> + * <p/> + * <p> This method satisfies the general contract of the {@link + * Object#equals(Object) Object.equals} method. </p> + * + * @param ob The object to which this object is to be compared + * @return <tt>true</tt> if, and only if, the given object is + * a VirtualMachineDescriptor that is equal to this + * VirtualMachineDescriptor. + */ + public boolean equals(Object ob) + { + if (ob == this) + return true; + if (!(ob instanceof VirtualMachineDescriptor)) + return false; + VirtualMachineDescriptor other = (VirtualMachineDescriptor) ob; + if (other.provider() != this.provider()) { + return false; + } + if (!other.id().equals(this.id())) { + return false; + } + return true; + } + + /** + * Returns the string representation of the <code>VirtualMachineDescriptor</code>. + */ + public String toString() + { + String s = provider.toString() + ": " + id; + + if (displayName != id) { + s += " " + displayName; + } + + return s; + } +} |